Assessing Biodegradation and Flame retardation in Bio- Fiber Reinforced Polymer Composites for Advanced Material Applications

Assessing Biodegradation and Flame retardation in Bio- Fiber Reinforced Polymer Composites for Advanced Material Applications | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Assessing Biodegradation and Flame retardation in Bio- Fiber Reinforced Polymer Composites for Advanced Material Applications Asmaa Mohamed Ghanem This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5670902/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: The demand for sustainable materials has driven interest in biodegradable polymer composites reinforced with natural fibers as eco-friendly alternatives to synthetic materials. These composites combine biodegradability with enhanced mechanical performance, using fibers like jute and hemp to strengthen polymer matrices while reducing environmental impact. Challenges such as water absorption and limited durability are mitigated through surface treatments and compatibilizers. Biopolymers like polylactic acid (PLA) and polyhydroxyalkanoates (PHA) naturally degrade under various conditions, making them suitable for biomedical and industrial applications. This study explores the potential of bio-fiber composites to balance environmental sustainability with high-performance requirements. My study aims to determine their suitability for sustainable engineering and industrial applications, in keeping with the global demand for ecologically responsible material advances. Results: This experimental laboratory-based study with analytical and comparative elements, conducted at Alexandria University's Department of Materials Science. Results show enhanced tensile strength (up to 201 kg/cm²) and flame retardancy (Limiting Oxygen Index of 31) with increased bio-fiber content, achieving improved thermal stability and reduced toxic gas emissions. Thermal analyses highlight significant char formation that protects the composite at high temperatures, while water absorption tests confirm improved hydrophobicity due to fiber treatment. Biodegradability tests reveal progressive weight loss over 14 days, validating eco-friendliness. The findings demonstrate the composite's suitability for biomedical and industrial applications, balancing environmental sustainability with performance demands. Conclusions: The study assesses biodegradation and water resistance of bio-fiber reinforced polymer composites, revealing their potential for advanced applications, including fire and antibacterial testing, enhancing tensile strength and thermal stability. Biodegradation Sustainability Bio-Fiber Polymer Composites Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Background Polymer-based composites are an important class of materials used in all fields, such as medicine, automotive, construction, home, textiles, and aviation. [ 1 ]. The majority of polymers used in composites are petroleum-based, nonrenewable, and non-biodegradable, polluting the environment and impacting all forms of life on Earth. Growing demand for polymeric composite materials in various sectors is one of the reasons for uncontrolled manufacturing and extensive use of petroleum-based polymers and synthetic fibers, resulting in faster depletion of valuable nonrenewable resources, increased health issues [ 2 ], and pollution [ 3 ]. Rapid growth in the manufacturing industries has prompted material improvements in terms of density, stiffness, strength, and cost-effectiveness while increasing sustainability. Composite materials have been produced as one of the materials with such advancements in properties that serve their promise in a variety of applications. Composite materials have two or more constituents, one of which is in the matrix phase (synthetic or biopolymer) and the other in particle or fiber form. Composites have been identified as the most promising material available in the twenty-first century. Composites reinforced with synthetic or natural fibers are becoming increasingly popular as the market demands lightweight materials with high strength for specialized applications. The matrix, which largely holds the reinforcement together, is also referred to as resin, especially in the case of polymers [ 4 ]. Biodegradable polymers, whether generated from nature or synthesized, can be degraded by biosphere enzymes in the presence of the right pH and temperature [ 5 ]. Biopolymers are plant, animal, and microbial-derived biodegradable polymers [ 6 ]. They are readily available renewable resources that are commonly used to make environmentally acceptable bio plastics [ 7 ]. According to the opposing viewpoint, the most straightforward method for classifying biodegradable polymers is based on their natural and synthetic origins. Natural biodegradable polymers are derived from polysaccharides, proteins, and microorganisms, whereas synthetic biopolymers are those created through microbial fermentation or biotechnological manufacturing [ 8 ]. Biopolymers can be classified into three types based on their heat response: elastomers, thermosets, and thermoplastics. Biopolymers are used in various applications based on their cost, availability, moisture absorption, thermal stability, mechanical behavior, degradation stability, and biocompatibility. PLA and PHAs are the two most often utilized biopolymers for manufacture and application [ 9 ]. The primary advantage of biodegradable polymers over non-biodegradable polymers is their decomposition by microbes, which returns them to the soil and enriches it. This stabilizes the environment and reduces rubbish volume. The breakdown capability of biodegradable polymers is determined by a variety of parameters, including polymer type, chemical content and environmental circumstances [ 10 ]. Despite their widespread use, biopolymers have a few drawbacks, including their hydrophilic nature, limited mechanical strength, and slower breakdown rate in damp settings [ 11 ]. Biodegradable polymers can be classified according to their origin, production process, chemical content, and application. They can be broadly categorized according to their origin: (1) natural polymers produced from renewable resources such as plants, animals, and microbes; and (2) biodegradable polymers synthesized from petrochemical products [ 12 ]. According to Siracusa et al., biodegradable polymers can be divided into three categories: 1. Natural biodegradable polymers derived from natural and renewable resources, such as polysaccharides (starch, cellulose), lipids (oils), and proteins (silk, wool); 2. Synthetic biodegradable polymers, such as PLA and polycaprolactone (PCL); 3. Polymers produced by microbes and genetically modified bacteria, such as poly(hydroxyalkanoates) (PHAs) [ 13 ]. The growing demand for sustainable materials has fueled research into biodegradable polymer composites, particularly those reinforced with natural fibers. These bio-fiber composites are regarded as environmentally beneficial alternatives to traditional materials because of their ability to reduce waste and dependency on fossil fuels. Biodegradable polymers, such as polylactic acid (PLA) and polyhydroxyalkanoates (PHA), breakdown spontaneously under a variety of environmental circumstances, making them appropriate for a wide range of applications, including packaging and biomedical equipment [ 14 ]. Bio-fiber reinforced composites are not only biodegradable, but also have excellent mechanical qualities. Natural fibers such as jute, flax, and hemp have been integrated into polymer matrices, increasing strength while remaining lightweight. This synergy is critical for applications in industries like automotive, construction, and packaging that value both performance and environmental impact [ 15 ]. However, there are hurdles for bio-composites, particularly in terms of water resistance and long-term durability. Water absorption by natural fibers can cause swelling and weakening of the composite material. To address this, researchers have looked into several surface treatments and fiber-matrix compatibilizers to increase the water resistance and overall performance of bio-fiber composites under environmental stress [ 16 ]. Overall, the development of bio-fiber reinforced composites that balance biodegradability and increased water resistance is crucial for their wider use in sustainable materials. The purpose of this study is to evaluate these qualities and provide insights that will help to drive the adoption of bio-composites in advanced material applications. METHODS 2.1- Study design & Study setting This is an experimental laboratory-based study with analytical and comparative elements done in Department of Materials Science, institute of Graduate Studies and Research, Alexandria University, from June 2023 to June 2024. The study involves laboratory testing and measurement to evaluate the biodegradation rates and water resistance of bio-fiber reinforced polymer composites. This includes subjecting the composites to specific environmental conditions (e.g., moisture, varying temperatures) to observe degradation behaviors and water absorption characteristics. The study may also include analytical methods, such as modeling biodegradation processes or water absorption kinetics, to interpret results and predict long-term performance. Statistical analysis could help validate the results and clarify the relationships between material properties and environmental resilience. Application-Oriented Research As the research targets advanced material applications, it will likely include an assessment of how the findings relate to real-world applications, with a focus on durability and functional performance under stress. This approach will provide a comprehensive understanding of the material properties necessary for sustainable, high-performance applications in fields such as automotive, aerospace, and construction. 2.2- Chriteria of Materials: 2.2-A Inclusion criteria : Material Composition: bio-fiber reinforced polymer composites using natural fibers (e.g., jute, flax, hemp) and biodegradable polymers like PLA, PHA, or other bio-based resins. Biodegradation and Water Resistance Testing: evaluate the following properties: biodegradation rate, water absorption, swelling behavior, or water resistance under different environmental conditions. Advanced Applications: advanced material applications, such as automotive, aerospace, construction, and packaging, will be included to ensure relevance to industrial and technological use cases. 2.2-B- Exclusion criteria : Non-Biodegradable Polymers: synthetic polymers (e.g., polyethylene, polypropylene) without biodegradable content would be ignored; studies that do not assess the water resistance or biodegradation qualities of composite materials will be rejected. Non-Composite Materials: pure bio-fibers or polymers without a composite matrix (i.e., reinforcement) will be prohibited. Non-Advanced Applications: low-end applications, such as single-use items with no durability requirements, will be excluded as the focus is on materials for advanced and durable applications, insufficient experimental, numerical, or analytical data on material qualities will be eliminated. 2.3- Experimental Procedures : 2.3.A- Pre- Experimental procedure : Materials 1. Bagasse Fibers (BFs) : The samples were cut into 5–10 mm lengths, immersed in distilled water for 24 hours to eliminate contaminants, filtered, and thoroughly washed before drying in an oven at 80⁰C for 24 hours. After drying, the fibers were crushed using a high-speed mixer and passed through an 80-mesh screen before being stored in sealed plastic bags. Bagasse Fibers' chemical makeup is 45.47% cellulose, 26.18% hemicellulose, 20.90% lignin, 1.64% ash, and 4.55% extractives. 2. High-density polyethylene (HDPE) (HDPE 5502 - GA) with density 0.955 g/cm3 and meltflow index 0.2 g/10 min was obtained from Sidi-Kerir Petrochemicals Company (SIDIPEC) in Egypt. 3. Synthesis of rennet casein (RC) Rennet casein was produced from skimmed milk using a documented method (Singh, 2009). The synthesis involved coagulating milk in a glass beaker at 40℃ with calf rennet for 60 minutes to produce rennet casein. The coagulum was then boiled at 50–55°C for 45 seconds before being separated into whey. Finally, the recovered rennet casein was washed multiple times in DI and dried at 40°C. Methods 1) FIBERS TREATMENT: The fibers were immersed in an aqueous solution containing (RC) at a concentration of 5 wt %. The mixture was then cooked in an oven for an hour. After heating, the fibers were taken from the RC solution and dried in an oven at 70 ⁰C for 15 hours. 2) SAMPLE PREPARATION I. Compounding Compounding was made using a two roll mill machines (Betol Machinery Ltd- UK) at 150°C. Firstly, the HDPE was added for 3 min and after starting to melt, treated bagasse fibers were add for 3 min, the weight of bagasse fibers and HDPE in the samples sheets was varied from Sheet 1 to Sheet 6 with compositions {100% HDPE} /{50%HDPE + 50% BF} / {40%HDPE + 60% BF}/ {30%HDPE + 70% BF}/ {20%HDPE + 80% BF}/ {10%HDPE + 90% BF} respectively. This variation in the bio-fiber reinforced polymer composite sheets composition, each with a different ratio of HDPE (high-density polyethylene) and bio-fiber (BF) treated with rennet casein will shed light on how bio-fiber content affects biodegradability, mechanical, flammability, and thermal properties, all of which will be significant to advanced material applications. II. Sheet molding processing : A compression molding machine (HEXA PLAST - INDIA) was utilized to create polymer sheets. The temperature was 160 ± 10°C, and the applied pressure was 20 tons for 10 minutes. The sheets' measurements were (200*200*3 mm). 2.3.B- CHARACTERIZATION OF THE PREPARED SHEETS Scanning electron microscope The dispersion of bagasse fibers into polymer was investigated using a Jeol model JSM-5300LV equipment. At Alexandria University's Faculty of Science, the samples were coated with a thin gold conducting layer using a fine coat JFC-110E. Fourier Transform Infrared (FTIR) FTIR was used to investigate the changes of Bagasse, high density polyethylene, and their composites. FTIR spectra were acquired using an FTIR spectrophotometer. The samples were formed as a disc and examined using a wave number range of 350–4400 cm-1 (Perkin Elmer GX model). Thermal properties TGA was performed using a 50/50H Shimadzu and thermal analysis software at a heating rate of 10⁰C/min in a nitrogen environment with a flow rate of 20ml/min. Thermal scans were conducted at temperatures ranging from 25 to 600⁰C, with an average specimen weight of 5 mg. 2.3.C- MEASUREMENTS OF THE PREPARED SHEETS 1. Flammability measurements The limiting oxygen index (LOI) was determined using an oxygen index meter in accordance with ASTM D2863-77.The samples' dimensions were 120 mm × 6.5 mm × 3 mm. The rate of burning of untreated and treated samples was determined using a Fire Testing Technology UL94 flame chamber in accordance with modified ISO 3795. Furthermore, the released hazardous gases were quantified using Testo 300 following sample burning in the LOI test. The identified gases were CO and CO2. Mechanical properties 1. Tensile properties. Tensile characteristics were determined at the Plastic Technology Center using a universal mechanical machine (Instron, Model 3382) in compliance with ASTM 882 − 570. Three samples (3mm thick) were evaluated for each formulation, with the average value reported. 2. Hardness Hardness was determined at the Plastic Technology Center using a shore (D) durometer in accordance with ASTM D-2240. An average of three measurements was taken. Water absorption The water absorption test was done according to ASTM- D 570 − 98 (85) to find out if the presence of bagasse fibers leads to higher water absorption of composites. Percentage increase in weight during immersion was calculated to the nearest 0.01% as follows: Percent Water Absorption = [(Wet weight - Dry weight)/ Dry weight] x 100 All presented values are average of three determinations Biodegradability of sheets The biodegradability of the composite films was assessed using a soil burial test, as described by Medina-Jaramillo et al. [ 18 ] and Patil et al. [ 19 ]. The test was performed in a transparent plastic box filled with dirt. The film samples were cut into 2 × 2 cm pieces, weighed, and then buried in the soil at an ambient temperature of 27.5°C and relative humidity (RH) of 70.5%. Water was sprayed twice daily to keep the soil hydrated. The film samples were removed at regular intervals (WEEK 1–WEEK 2) by rinsing with water to remove adhering soil, and the dry weight of recovered samples was calculated to evaluate the rate of film breakdown and weight reduction. 2.4- Statistical Analysis : The mechanical, thermal, and flame-retardant properties of bio-fiber reinforced polymer composites with different bio-fiber (BF) concentrations were investigated. Tensile strength, hardness, elongation, Limiting Oxygen Index (LOI), Time to Ignition (TTI), and thermal deterioration stages were analyzed for six composite formulations each. Comparisons were done between groups (for example, HDPE and composites with higher BF content). A one-way ANOVA or Kruskal-Wallis test would be adequate for determining differences between formulations based on data normality. Power Calculation and Sample Size To reach 80% statistical power at a significance level of 0.05 to detect noteworthy differences in tensile strength (e.g., 15% improvement from Sheet 1 to Sheet 6), we used the observed standard deviation (± 5 kg/cm², estimated from the findings). Calculations indicate that a sample size of 6 sheets per formulation is sufficient for detecting variances across many metrics, including LOI and TTI. Results Our experimental studies show: Mechanical Properties Tensile strength increased from 90 kg/cm² (pure HDPE) to 201 kg/cm² (Sheet 6); elongation decreased due to rigidity. Flammability LOI improved from 17 (HDPE) to 31 (Sheet 6), and TTI rose from 25 to 217 seconds. Thermal and Biodegradability Improved char formation and reduced CO emissions correlate with enhanced flame retardancy; progressive weight loss over 14 days confirmed biodegradability. Table No 1 Mechanical, flammability and DSC results Properties Sheet1 Sheet2 Sheet3 Sheet4 Sheet5 Sheet6 Mechanical tests Tensile strength(kg/cm ₂ ) 90 180 195 198 200 201 hardness ( shore 65 84 86 86 88 90 Elongation (%) 8.7 4.2 3.8 3.6 3.6 3.5 Flammability measurements LOI 17 28 29.5 29.5 31 31 TTI (S) 25 194 199 210 215 217 Toxic gases emitted CO (PPm) 0.017 0.0189 0.016 0.0135 0.0129 0.0125 CO 2 ppm 2.082 1.473 1.328 1.279 1.25 0.645 Differential scanning calorimeter Tg ○ C 126.49 127.85 127.18 127.27 127.36 127.78 Melting enthalpy(J/g) 108.27 87.53 84.12 83.45 82.41 74.81 a. Data presented as number and percentages as appropriate. b . Abbreviations : LOI : Limiting oxygen index . TTI : Time to Ignition . This table compares the properties of various bio-fiber reinforced polymer composite sheets, each with a different ratio of HDPE (high-density polyethylene) and bio-fiber (BF) treated with rennet casein. The findings shed light on how bio-fiber content affects mechanical, flammability, toxicity, and thermal properties, all of which are significant to advanced material applications. Key observations and interpretations: 1. Mechanical properties: o Tensile strength increases with bio-fiber concentration, from 90 kg/cm² in pure HDPE (Sheet 1) to 201 kg/cm² in Sheet 6, the highest BF percentage. This shows that bio-fiber reinforcement significantly improves tensile strength, making the composite stronger as the bio-fiber proportion increases. o Hardness (Shore scale) increases with bio-fiber content, from 65 in pure HDPE to 90 in Sheet 6. The increased hardness implies improved rigidity with added fiber, which is advantageous for structural applications where stiffness is important. o Elongation percentage falls with increasing BF concentration, from 8.7% in Sheet 1 to 3.5% in Sheet 6. This decrease implies a reduction in flexibility, most likely due to the reinforcing impact of bio-fibers, which make the composite more rigid but less ductile. 2. Flammability Measurements: o The limiting oxygen index (LOI) increases significantly with greater BF content, from 17 in pure HDPE to 31 in Sheet 6. A higher LOI value indicates that bio-fiber and resin treatment improves the composite's fire resistance. o Time to Ignition (TTI) increases dramatically with BF content, from 25 seconds in Sheet 1 to 217 seconds in Sheet 6, indicating that bio-fiber reinforced sheets take longer to ignite., enhancing fire safety. o Toxic Gas Emissions : o Increased bio-fiber content significantly reduces carbon monoxide (CO) emissions. Sheets with larger quantities of bio-fiber emit less CO, with values ranging from 0.017 ppm in pure HDPE to 0.0125 ppm in Sheet 6. Lower CO emissions improve material safety in fire scenarios by limiting hazardous gas exposure. o CO₂ Emissions drop as BF concentration increases, from 2.082 ppm in Sheet 1 to 0.645 ppm in Sheet 6. Composites with lower CO₂ emissions may have environmental benefits, particularly during incineration or accidental fire exposure. 3. Thermal Properties (Differential Scanning Calorimetry - DSC): o The glass transition temperature (Tg) is very consistent across sheets, with small fluctuations around 127°C. This suggests that the bio-fiber content has no substantial impact on the composite's thermal stability in this transition range. o Melting Enthalpy reduces as BF concentration increases, from 108.27 J/g in pure HDPE to 74.81 J/g in Sheet 6. Lower melting enthalpy in higher BF-content sheets indicates a lower degree of crystallinity, which is most likely related to the bio-fiber's amorphous structure. This alteration may have an impact on the material's melting behavior and energy needs during processing. Table 2: The thermal degradation stages of composite sheets Stages Unit BF Sheet (1) Sheet (2) Sheet (3) Sheet (4) Sheet (5) Sheet (6) First Stage start (ºC) 25.8 254.9 187 165 148 138 110 end (ºC) 130 490.4 291 270 286 293 295 Weight loss (% ) -8.412 -2.67 -5.87 -11.99 -13.61 -15.22 -17.16 Second Stage start (ºC) 212 251 270 286 293 295 end (ºC) 356.8 420 429 417 421 460 Weight loss (% ) -55.4 -9.47 -11.56 -12.18 -14.27 -16.85 Third Stage start (ºC) 356.8 420 429 417 421 460 end (ºC) 530 506 519 514 580 590 Weight loss (% ) -29.7 -71.05 -48.87 -46.29 -44.09 -48.05 Total Weight loss (% ) -93.5 -99.67 -86.39 -79.42 -76.07 -73.12 -70.06 Residue (% ) 6.4 0.33 13.61 20.58 23.93 26.05 29.94 a) Data presented as number and percentages as appropriate. The table provides insight into the thermal degradation profile of bio-fiber reinforced polymer composites, focusing on the weight loss and thermal stability of each sheet throughout three stages. This information is crucial for determining the biodegradability and heat resilience of the composites. Key Observations and Analysis: 1. Thermal Degradation Stages: The composite sheets degrade in three stages, each with unique structural responses to growing temperatures. v First Stage (Low-Temperature Degradation): o As bio-fiber (BF) content increases, the starting temperature for degradation lowers from 254.9ºC to 110ºC in Sheets 1–6. Pure HDPE (Sheet 1) is more thermally stable at this point, but more BF content renders the composite more vulnerable to initial breakdown, probably due to the natural fibers' poorer thermal resistance. o Weight loss in the first stage increases with BF concentration, from 2.67% in Sheet 1 to 17.16% in Sheet 6. This is presumably due to breakdown of bio-fiber materials, which are more thermally labile than HDPE. v Second Stage (Mid-Temperature Degradation): o In the second step, the degradation temperature rises from 251ºC in Sheet 2 to 295ºC in Sheet 6, indicating greater BF concentration. This range could correspond to the breakdown of stronger bio-fiber and polymer matrix components. o BF-rich sheets have the maximum weight loss, with values ranging from 9.47% in Sheet 2 to 16.85% in Sheet 6, indicating that the bio-fiber content contributes to greater mass loss at these temperatures. v Third Stage (High-Temperature Degradation): o The final stage involves high-temperature deterioration, with beginning temperatures ranging from 420ºC in Sheet 3 to 460ºC in Sheet 6. o Weight loss is high at this stage, particularly for sheets with reduced BF content, such as Sheet 3 (71.05% weight loss). Weight loss decreases as BF content increases, indicating that the composite structure provides superior residual stability at higher temperatures, probably due to bio-fiber char production. 2. Overall Thermal Stability and Total Weight Loss: o Weight loss reduces with higher BF content, from 99.67% in Sheet 1 to 70.06% in Sheet 6. Higher BF content appears to improve thermal stability in the composite by leaving more residual mass after heating. This tendency shows that bio-fiber increases char formation, resulting in a protective coating that improves heat resistance at high temperatures. o Residue Formation: The proportion of residue after the entire thermal cycle rises with BF content, from 0.33% in Sheet 1 to 29.94% in Sheet 6. This residue is most likely composed of stable char or inorganic chemicals, indicating the ability of BF composites to maintain structure and resist full disintegration under high-temperature settings. Implications for Material Applications: The results indicate that incorporating higher bio-fiber content in HDPE composites improves char formation, lowers total weight loss, and provides a protective effect during thermal degradation. While higher BF content results in earlier onset degradation in low-temperature stages, it ultimately contributes to greater thermal resistance in later stages. This suggests that BF-reinforced composites are more suitable for applications requiring both biodegradability and moderate heat resistance, such as packaging, automotive parts, and construction materials, where partial degradation is beneficial for environmental applications, but some structural stability at elevated temperatures is also required. Conclusion This study effectively assessed the biodegradation and water resistance capabilities of bio-fiber reinforced polymer composites, indicating the feasibility of combining bagasse fibers (BFs) with recycled high-density polyethylene (HDPE) for advanced material applications. Rennet casein (RC) treatment of fibers enhanced compatibility with the HDPE matrix, resulting in improved mechanical and thermal properties. Summary The data demonstrate that adding bio-fibers improves tensile strength, hardness, flame resistance, and reduces hazardous gas emissions, making these composites more suited for applications that need fire resistance and structural integrity. However, reduced elongation and melting enthalpy in high-BF sheets suggest a trade-off between flexibility and processing behavior. These findings are critical for optimizing the composition of bio-fiber reinforced composites for specific advanced applications while maintaining biodegradability, mechanical performance, and environmental effect. 1. Comparative analysis: It would be beneficial to test these sheets in similar environmental settings in order to observe and quantify the trade-offs between biodegradability and water resistance. This comparative research will highlight the balance of environmental benefits and durability for various material uses. This composition-based framework offers a straightforward experimental design for investigating the balance of biodegradability and durability in bio-fiber reinforced polymer composites. It will be useful to assess how each sheet performs in real-world situations, providing information on the viability of these composites for advanced material applications where both environmental impact and material durability are crucial. 3. Fourier Transform Infrared analysis (FTIR) IR spectrum of PE shows two peaks at 2919cm-1 and 2859cm-1 which are attributed to CH asymmetric and symmetric stretch vibrations respectively. A peak at 1464 cm-1 is due to CH2 bending vibration, and a peak at 719 cm-1 is assigned to CH2 rocking. IR spectrum of BFs shows the peaks at 3429 cm-1,2897 cm-1,1637 cm-1 and 1072 cm-1 which are attributed to -OH originating mainly from cellulose, C-H stretching vibration, C=C stretching vibration and C-O stretching respectively. The spectra of sheet4 composite show peak at 894 cm-1. These peaks indicate the formation of phosphorus ester which is formed as a result of the reaction of phosphoric acid with some hydroxyl groups of the fibers. 4. Surface Morphology using Scanning Electron Microscope It is well known that fiber-matrix interface plays a major role in composite properties. A Strong interface bond is critical for the high performance of the composite. SEM was used to investigate the morphology and the possible interfacial adhesion for the composite. SEM micrograph of HDPE [figure below], revealed that PE has homogeneous and smooth uniform surface. For the composite sheets, the compatibility between the matrix and the treated fibers making the interfacial boundary indistinct, and BFs were highly distributed in the matrix which gives the composite homogeneous structure [figure (5). Figure (5) show SEM images of the treated BFs. The particles observed in the figure are casein flame retardant which adsorbs on BFs or spread between the fibers, giving smoother surface morphology. This confirmed that there are some modifications on the surface of the fibers after treatment. This result agrees with Branca and Di Blasi [20]. When the treated BFs were used to reinforce HDPE, they were well distributed in the PE matrix Figure 6: show: This scanning electron micrograph (SEM) shows the surface morphology of treated bio-fibers (BFs) utilized in a polymer composite. The image shows how the treatment process affects the fiber structure, with increased surface roughness and improved interfacial properties. These surface changes are critical for improving fiber-matrix bonding in polymer composites. The evident textural changes and impurity elimination indicate that the treatment method successfully activated the fiber surface, potentially contributing to increased water resistance and biodegradation control in the final composite material. This increase is consistent with the goal of improving mechanical characteristics and environmental sustainability in advanced material applications. Table 3: Water absorption test Specimens Water absorption(%) SHEET1 0.0194 SHEET2 0.0088 SHEET3 0.0057 SHEET4 0.0039 SHEET5 0.0026 SHEET6 0.00146 a- Data presented as number and percentages as appropriate. Material Composition and Water Resistance Expectation: Sheet 1 is a control sample made of pure HDPE. Given HDPE's hydrophobic qualities, this sheet will most likely be highly water resistant, yet with limited biodegradation potential. Sheets 2-6 steadily raise BF content from 50% to 90% by substituting HDPE. Bio-fibers are typically more hydrophilic; therefore as the BF content grows, water resistance may decrease due to the fibers' ability to absorb moisture. This may impact the material's dimensional stability in damp situations. It is well established that water absorption of natural fiber is mainly due to the presence of hydrogen bonding sites. In case of composites reinforced with BFs (sheet 4), the use of casein has a beneficial effect on the water absorption of the composites. This may be explained, first by the promoted dispersion of BFs in the polymer matrices which improved the interfacial adhesion between BFs and the polymer matrices that slowed down the water diffusion rate in the BFs through interfacial defects. Second due to the esterification reactions of BFs with phosphoric acid released from RC, which reduced the number of hydroxide groups in BFs. R-OH +HO-PO-(OH) 2 →R-O-PO-(OH) 2 +H2O Flammability Measurements Limiting oxygen index (LOI) LOI value of HDPE is 17.5 and it is considered as a combustible material since its LOI value is less than 22. When BFs was treated with RC and used to reinforce the polymer with different percentages a flame retardancy effect is achieved. This may be due to the formation of a very thick char layer which acts as a barrier to prevent heat and fuel gas from transferring. So RC is an efficient flame retardant for the composites. Time to ignition (TTI) Sheet 1 exhibits shorter TTI (18 sec.) which is due to the degradation of the matrix. TTI of the composites occurs at a lower temperature (350-380 ⁰C) than the degradation of PE (390 ⁰C). This observation coincides with the TGA and DTG results which explain the effect of BFs on the thermal behavior of the composites. The flammability behavior of the composites was wholly changed when BFs were treated with RC. TTI was longer for specimens containing higher content of BF . This behavior can be attributed to the formation of a protective char layer at the surface of the sample which provides an efficient barrier against the propagation of the flame. Carbon monoxide (CO) yield one important reaction to fire is the formation of carbon monoxide. The formation of carbon monoxide at the expense of carbon dioxide is an important fire retardant parameter. The composites containing RC show an average carbon monoxide yield reduction (Table1). This observation confirms that RC does not increase the formation of toxic carbon monoxide in comparison with the untreated composite. Also BFs undergo long-term glow during and after burning the specimens which is ascribed to the so-called "candlewick effect". When RC (the active component) was used, it reacted with the surface of the cellulosic fibers causing the formation of phosphorus esters. These esters catalyze the dehydration of cellulose, promoting the formation of char and water at the expense of levoglucosan and prevent the heat and flame propagation along the fibers which could be effectively suppressed. Thus the extinction of the candlewick effect was possible and as a consequence, Also, the homogeneous dispersion of the treated BFs (shown in SEM) influences the burning behavior and improves TTI values. Increasing treated BF content in the composites attributes a compact intumescent char layer that is formed on the surface of the sample during the combustion which suppresses the release of smoke. The morphology of the charred residue obtained at the end of combustion process plays a significant role in the performance of the flame retardant. The surface of the polymer residue was covered with an expanded char network but it was thin and destroyed during combustion which indicates that the surface morphologies disintegrated entirely and tended to form ash after glowing. The appearance of the increased char in the case of RC treated composites was distinct in that there was no glowing and the char residue was thick in comparison with the untreated composite. This char protects the underlying composite from further burning indicating that the treated composites have a better flame retardancy. Table 4: Biodegradability of sheets SAMPLES INITIAL WEIGHT AFTER 7 DAYS AFTER 14 DAYS SHEET 1 2.5 2.12 1.97 SHEET 2 1.3 0.87 0.74 SHEET 3 1.2 0.74 0.62 SHEET 4 1.2 0.79 0.68 SHEET 5 1.1 0.71 0.63 SHEET 6 1 0.66 0.54 a- Data presented as numbers as appropriate. Implications for Material Applications: The results indicate that incorporating higher bio-fiber content in HDPE composites improves char formation, lowers total weight loss, and provides a protective effect during thermal degradation. While higher BF content results in earlier onset degradation in low-temperature stages, it ultimately contributes to greater thermal resistance in later stages. This suggests that BF-reinforced composites are more suitable for applications requiring both biodegradability and moderate heat resistance, such as packaging, automotive parts, and construction materials, where partial degradation is beneficial for environmental applications, but some structural stability at elevated temperatures is also required. Discussion Mechanical Properties Bio-fiber reinforcement effectively improves tensile strength (from 90 kg/cm² in pure HDPE to 201 kg/cm² in Sheet 6), consistent with findings by Siracusa et al. [20], who found that natural fiber integration improved mechanical properties of polymer composites. Similarly, the reported rise in hardness (Shore D) to 90 in Sheet 6 is consistent with other studies of increased rigidity in fiber-reinforced composites. However, the drop in elongation percentage from 8.7% in Sheet 1 to 3.5% in Sheet 6 suggests a trade-off, as reported by Watanabe et al., [21], who noted decreased flexibility with greater fiber content due to the inflexible reinforcement structure. Flammability Measurements The rise in Limiting Oxygen Index (LOI) from 17 to 31 across the sheets demonstrates that bio-fiber and RC treatment improves fire resistance, which is consistent with Branca and Di Blasi's [19] observations on flame-retardant composites. Furthermore, the increase in Time to Ignition (TTI) from 25 seconds in Sheet 1 to 217 seconds in Sheet 6 illustrates the protective impact of the char layer created during combustion, as previously observed by Ogura et al. [22]. Efficient char formation reduces toxic emissions, including CO (from 0.017 ppm to 0.0125 ppm) and CO₂ (from 2.082 ppm to 0.645 ppm). This aligns with Choi et al.'s [23] findings of reduced toxic emissions in fire-retardant bio-composites. Thermal Properties The glass transition temperature (Tg) staying reasonably stable (about 127°C) across all sheets implies that bio-fiber content does not greatly alter thermal stability in the transition region, which is consistent with research by Patil et al. [18]. However, the decrease in melting enthalpy (from 108.27 J/g in pure HDPE to 74.81 J/g in Sheet 6) represents the lower crystallinity with increased bio-fiber content, as seen in Medina-Jaramillo et al.'s [18] study on starch-based composites. The staged thermal degradation investigation demonstrates that when bio-fiber content increases, breakdown begins earlier, but char formation improves and residue levels increase (from 0.33% in Sheet 1 to 29.94% in Sheet 6). This is consistent with Branca and Di Blasi [19], who emphasized bio-fiber's involvement in enhancing residual stability via char generation during burning. Implications for Biodegradation The observed biodegradation patterns, with increased bio-fiber content permitting larger weight loss, are consistent with studies by Nakai et al. [24], who showed similar behavior in natural fiber-reinforced composites. Sheets with a larger bio-fiber content (e.g., Sheet 6) disintegrate more dramatically in the early thermal stages but show better structural stability at higher temperatures, balancing biodegradability with durability for advanced applications. Comparative Perspective and Contributions Compared to untreated fiber composites, RC-treated bio-fiber reinforced HDPE composites have higher water resistance, biodegradability, and mechanical integrity. These findings are consistent with, but expand on, the research of Medina-Jaramillo et al. [18] and Patil et al. [17], demonstrating how fiber treatment optimizes these properties for a variety of applications. Future research should focus on improving fiber treatment methods to increase water resistance while retaining biodegradability and thermal performance for practical applications. 6-Conclusion: The study evaluates the biodegradation and water resistance of bio-fiber reinforced polymer composites, highlighting the potential of bagasse fibers and recycled HDPE for advanced applications. The composites show increased tensile strength, hardness, and thermal stability, with a balance between biodegradability and water resistance. Fire testing and antibacterial testing confirm their flammability and potential hygienic applications. Abbreviations HDPE: High density polyethylene. TGA: Thermogravimetric analysis. FTIR: Fourier Transform Infrared. SEM: Scanning electron microscopy. RC: Rennet casein. BFs: Bagasse fibers. LOI: Limiting oxygen index: DSC: Differential Scanning Calorimetry. TTI: Time to Ignition PLA: polylactic acid. PHA: Polyhydroxyalkanoates. PCL: Polycaprolactone. Declarations Ethics approval and consent to participate The study did not include any human participants, animal subjects, or activities that would require ethical approval from an institutional review board. All experimental methods were carried out in compliance with normal laboratory safety protocols and guidelines. Because no humans or animals were involved, formal agreement to participate is not required for this study. Consent for publication The study did not include human participants, animal subjects, or other activities that required ethical approval from an institutional review board. All experimental methods were carried out in compliance with established laboratory safety norms and regulations. Because no human or animal participants were engaged, formal consent to participate is not required for this study. Availability of data and materials The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request. All materials and methodologies used in this research; including bagasse fiber preparation, rennet casein treatment, and composite fabrication, are detailed in the study to ensure reproducibility. Access to specific analytical tools or facilities mentioned, such as SEM and FTIR instrumentation, can be arranged through respective institutions as required. Competing interests The author declare that they have no competing interests related to this study. This includes no financial, professional, or personal relationships that could influence or appear to influence the research or its interpretation. Funding Funding There was no funding provided to the author for this study. Authors' contributions Conceptualization & Data collection: Asmaa Mohamed Ghanem. Methodology: Asmaa Mohamed Ghanem. Writing & Software : Asmaa Mohamed Ghanem. Supervision & editing: Asmaa Mohamed Ghanem. Acknowledgments The author would like to express their gratitude to (Department of Materials Science, institute of graduate studies and research, Alexandria University) for providing the necessary resources and facilities to conduct this research. Special thanks to the Plastic Technology Center, Alexandria, Egypt, for their support in mechanical property testing and the Faculty of Science, Alexandria University, for assisting with scanning electron microscopy (SEM) analysis. References Naghdi R (2021) Advanced Natural Fibre-Based Fully Biodegradable and Renewable Composites and Nanocomposites: A Comprehensive Review. Int Wood Prod J 12:178–193 Suran M (2018) A Planet Too Rich in Fibre. EMBO Rep 19:e46701 Walker TR, Fequet L (2023) Current Trends of Unsustainable Plastic Production and Micro(Nano)Plastic Pollution. TrAC Trends Anal Chem 160:116984 Ilyas RA, Sapuan SM, Bayraktar E, Hassan SA, Atikah MSN, Shaker K (2022) Fibre-Reinforced PolymerComposites: Mechanical Propertiesand Applications. Polymers 143732. https://doi.org/10.3390/polym14183732 Satyanarayana KG, Arizaga GGC, Wypych F (2009) Biodegradable Composites Based on Lignocellulosic Fibers—An Overview. Prog Polym Sci 34:982–1021 Bhagabati P (2020) Biopolymers and Biocomposites-Mediated Sustainable High-Performance Materials for Automobile Applications. Sustainable Nanocellulose and Nanohydrogels from Natural Sources. Elsevier, Oxford, UK, pp 197–216 Noor Azammi AM, Ilyas RA, Sapuan SM, Ibrahim R, Atikah MSN, Asrofi M et al (2019) Characterization Studies of Biopolymeric Matrix and Cellulose Fibres Based Composites Related to Functionalized Fibre-Matrix Interface. Interfaces in Particle and Fibre Reinforced Composites: Current Perspectives on Polymer, Ceramic, Metal and Extracellular Matrices. Woodhead Publishing, Sawston, UK Calori IR, Braga G, de Jesus PCC, Bi H, Tedesco AC (2020) Polymer Scaffolds as Drug Delivery Systems. Eur Polym J 129:109621 Christian SJ (2019) Natural Fibre-Reinforced Noncementitious Composites (Biocomposites). Nonconventional and Vernacular Construction Materials: Characterisation, Properties and Applications. Woodhead Publishing, Sawston, UK Nair NR, Sekhar VC, Nampoothiri KM, Pandey A (2017) Biodegradation of Biopolymers. Current Developments in Biotechnology and Bioengineering: Production, Isolation and Purification of Industrial Products. Elsevier, Oxford, UK, pp 739–755 Mohamed SAN, Zainudin ES, Sapuan SM, Azaman MD, Arifin AMT (2018) Introduction to Natural Fiber Reinforced Vinyl Ester and Vinyl Polymer Composites. Natural Fiber Reinforced Vinyl Ester and Vinyl Polymer Composites: Development, Characterization and Applications. Woodhead Publishing, Sawston, UK Ramesh M, Muthukrishnan M (2022) 25—Biodegradable Polymer Blends and Composites for Food-Packaging Applications. Biodegradable Polymers, Blends and Composites. Woodhead Publishing, Sawston, UK, pp 693–716 Ingrao C, Siracusa V (2018) 14—Quality- and Sustainability-Related Issues Associated with Biopolymers for Food Packaging Applications: A Comprehensive Review. Biodegradable and Biocompatible Polymer Composites. Woodhead Publishing, Sawston, UK, pp 401–418 Laycock B, Pratt S, Halley P (2023) A perspective on biodegradable polymer biocomposites - from processing to degradation. Funct Compos Mater 4:10. https://doi.org/10.1186/s42252-023-00048-w Pokharel A, Falua KJ, Babaei-Ghazvini A, Acharya B (2022) Biobased Polymer Composites: A Review. J Compos Sci 6:255. https://doi.org/10.3390/jcs6090255 Molla A, Moyeen AA, Mashfiqua Mahmud R, Haque MJ (2024) Plant fiber-reinforced green composite: A review on surface modification, properties, fabrications and applications [version 1; peer review: awaiting peer review]. Mater Open Res 3:6. https://doi.org/10.12688/materialsopenres.17651.1) Patil S, Bharimalla AK, Mahapatra A, Dhakane-Lad J, Arputharaj A, Kumar M, Raja A, Kambli N (2021) Effect of polymer blending on mechanical and barrier properties of starch-polyvinyl alcohol based biodegradable composite films. Food Biosci 44:101352. 10.1016/j.fbio.2021.101352 Medina-Jaramillo C, Ochoa-Yepes O, Bernal C, Famá L (2017) Active and smart biodegradable packaging based on starch and natural extracts. Carbohydr Polym 176:187–194. 10.1016/j.carbpol.2017.08.079 Branca C, Di Blasi C (2003) Multistep mechanism for the devolatilization of biomass fast pyrolysis. Ind Eng Chem Res 42(14):3190–3202. https://doi.org/10.1021/ie0300316 Siracusa V, Rocculi P, Romani S, Rosa MD (2008) Biodegradable polymers for food packaging: A review. Trends Food Sci Technol 19(12):634–643. https://doi.org/10.1016/j.tifs.2008.07.003 Watanabe T, Itabashi M, Shimada Y, Tanaka S, Ito Y, Ajioka Y (2012) Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2010 for the treatment of colorectal cancer. Int J Clin Oncol 17(1):1–29. https://doi.org/10.1007/s10147-011-0315-2 Ogura H, Wang Q, Yamada T, Shibata S (2010) Development of flame-retardant biocomposites by using natural fiber and biodegradable resin. Compos Part A: Appl Sci Manufac 41(11):1561–1568. https://doi.org/10.1016/j.compositesa.2010.07.007 Choi GS, Kim JH, Kim HJ, Yang SY, Park JS (2009) Fire retardancy of wood-based composites treated with flame-retardant chemicals. J Appl Polym Sci 113(1):192–198. https://doi.org/10.1002/app.30103 Nakai A, Matsumoto T, Hamada H (2003) Mechanical properties of biodegradable composites reinforced with natural fibers. Proceedings of the 4th International Conference on Composite Materials, 11 , 1–6 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5670902","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":392331902,"identity":"f2dfe34c-2856-48aa-96b6-9823a0d08c0d","order_by":0,"name":"Asmaa Mohamed 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2","display":"","copyAsset":false,"role":"figure","size":21737,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFTIR Spectrum of Sugarcane bagasse (BF)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/fc114503c24c1fa21ffa2eb6.png"},{"id":72141434,"identity":"3d501110-69b5-472a-99f2-cbcb98761ed9","added_by":"auto","created_at":"2024-12-23 06:40:47","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":120498,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eshows, the FTIR spectra of Sheet(4)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/30b64870583e1b771db306c7.png"},{"id":72141611,"identity":"e5d67330-cfbf-45d2-8666-691fa2f1a920","added_by":"auto","created_at":"2024-12-23 06:48:47","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":313389,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSEM of polymer matrix\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/79470c5d7236016696e91a7e.png"},{"id":72141450,"identity":"a5778397-2f85-48b2-bc6f-d416f7f5ab3e","added_by":"auto","created_at":"2024-12-23 06:40:47","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":332846,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSEM of composite sheet (6)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/77f680b50451a3fc5794e07c.png"},{"id":72141457,"identity":"a621087f-b0f9-4bad-9134-ea81117625f3","added_by":"auto","created_at":"2024-12-23 06:40:47","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":267601,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSEM of treated BFs\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/b1dd6f8ffa71cf2f8facf06f.png"},{"id":78838351,"identity":"4d7952a2-a9a1-4a3a-bc40-56ea2a30c560","added_by":"auto","created_at":"2025-03-19 15:16:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2746646,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5670902/v1/d9e60114-27e4-4ad0-b55b-ee6155f93d03.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Assessing Biodegradation and Flame retardation in Bio- Fiber Reinforced Polymer Composites for Advanced Material Applications","fulltext":[{"header":"Background","content":"\u003cp\u003ePolymer-based composites are an important class of materials used in all fields, such as medicine, automotive, construction, home, textiles, and aviation. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe majority of polymers used in composites are petroleum-based, nonrenewable, and non-biodegradable, polluting the environment and impacting all forms of life on Earth. Growing demand for polymeric composite materials in various sectors is one of the reasons for uncontrolled manufacturing and extensive use of petroleum-based polymers and synthetic fibers, resulting in faster depletion of valuable nonrenewable resources, increased health issues [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], and pollution [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRapid growth in the manufacturing industries has prompted material improvements in terms of density, stiffness, strength, and cost-effectiveness while increasing sustainability. Composite materials have been produced as one of the materials with such advancements in properties that serve their promise in a variety of applications. Composite materials have two or more constituents, one of which is in the matrix phase (synthetic or biopolymer) and the other in particle or fiber form. Composites have been identified as the most promising material available in the twenty-first century. Composites reinforced with synthetic or natural fibers are becoming increasingly popular as the market demands lightweight materials with high strength for specialized applications. The matrix, which largely holds the reinforcement together, is also referred to as resin, especially in the case of polymers [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBiodegradable polymers, whether generated from nature or synthesized, can be degraded by biosphere enzymes in the presence of the right pH and temperature [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBiopolymers are plant, animal, and microbial-derived biodegradable polymers [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThey are readily available renewable resources that are commonly used to make environmentally acceptable bio plastics [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAccording to the opposing viewpoint, the most straightforward method for classifying biodegradable polymers is based on their natural and synthetic origins. Natural biodegradable polymers are derived from polysaccharides, proteins, and microorganisms, whereas synthetic biopolymers are those created through microbial fermentation or biotechnological manufacturing [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBiopolymers can be classified into three types based on their heat response: elastomers, thermosets, and thermoplastics. Biopolymers are used in various applications based on their cost, availability, moisture absorption, thermal stability, mechanical behavior, degradation stability, and biocompatibility. PLA and PHAs are the two most often utilized biopolymers for manufacture and application [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe primary advantage of biodegradable polymers over non-biodegradable polymers is their decomposition by microbes, which returns them to the soil and enriches it. This stabilizes the environment and reduces rubbish volume. The breakdown capability of biodegradable polymers is determined by a variety of parameters, including polymer type, chemical content and environmental circumstances [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite their widespread use, biopolymers have a few drawbacks, including their hydrophilic nature, limited mechanical strength, and slower breakdown rate in damp settings [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBiodegradable polymers can be classified according to their origin, production process, chemical content, and application. They can be broadly categorized according to their origin: (1) natural polymers produced from renewable resources such as plants, animals, and microbes; and (2) biodegradable polymers synthesized from petrochemical products [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAccording to Siracusa et al., biodegradable polymers can be divided into three categories: 1. Natural biodegradable polymers derived from natural and renewable resources, such as polysaccharides (starch, cellulose), lipids (oils), and proteins (silk, wool); 2. Synthetic biodegradable polymers, such as PLA and polycaprolactone (PCL); 3. Polymers produced by microbes and genetically modified bacteria, such as poly(hydroxyalkanoates) (PHAs) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe growing demand for sustainable materials has fueled research into biodegradable polymer composites, particularly those reinforced with natural fibers. These bio-fiber composites are regarded as environmentally beneficial alternatives to traditional materials because of their ability to reduce waste and dependency on fossil fuels. Biodegradable polymers, such as polylactic acid (PLA) and polyhydroxyalkanoates (PHA), breakdown spontaneously under a variety of environmental circumstances, making them appropriate for a wide range of applications, including packaging and biomedical equipment [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBio-fiber reinforced composites are not only biodegradable, but also have excellent mechanical qualities. Natural fibers such as jute, flax, and hemp have been integrated into polymer matrices, increasing strength while remaining lightweight. This synergy is critical for applications in industries like automotive, construction, and packaging that value both performance and environmental impact [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, there are hurdles for bio-composites, particularly in terms of water resistance and long-term durability. Water absorption by natural fibers can cause swelling and weakening of the composite material. To address this, researchers have looked into several surface treatments and fiber-matrix compatibilizers to increase the water resistance and overall performance of bio-fiber composites under environmental stress [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOverall, the development of bio-fiber reinforced composites that balance biodegradability and increased water resistance is crucial for their wider use in sustainable materials. The purpose of this study is to evaluate these qualities and provide insights that will help to drive the adoption of bio-composites in advanced material applications.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eStudy design \u0026amp; Study setting\u003c/span\u003e\u003c/h2\u003e\n \u003cp\u003eThis is an \u003cstrong\u003eexperimental laboratory-based study with analytical and comparative elements\u003c/strong\u003e done in Department of Materials Science, institute of Graduate Studies and Research, Alexandria University, from June 2023 to June 2024. The study involves laboratory testing and measurement to evaluate the biodegradation rates and water resistance of bio-fiber reinforced polymer composites. This includes subjecting the composites to specific environmental conditions (e.g., moisture, varying temperatures) to observe degradation behaviors and water absorption characteristics. The study may also include analytical methods, such as modeling biodegradation processes or water absorption kinetics, to interpret results and predict long-term performance. Statistical analysis could help validate the results and clarify the relationships between material properties and environmental resilience.\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eApplication-Oriented Research\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eAs the research targets advanced material applications, it will likely include an assessment of how the findings relate to real-world applications, with a focus on durability and functional performance under stress. This approach will provide a comprehensive understanding of the material properties necessary for sustainable, high-performance applications in fields such as automotive, aerospace, and construction.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2- Chriteria of Materials:\u003c/h2\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2-A \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInclusion criteria\u003c/span\u003e:\u003c/h2\u003e\n \u003cp\u003eMaterial Composition: bio-fiber reinforced polymer composites using natural fibers (e.g., jute, flax, hemp) and biodegradable polymers like PLA, PHA, or other bio-based resins. Biodegradation and Water Resistance Testing: evaluate the following properties: biodegradation rate, water absorption, swelling behavior, or water resistance under different environmental conditions. Advanced Applications: advanced material applications, such as automotive, aerospace, construction, and packaging, will be included to ensure relevance to industrial and technological use cases.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2-B- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eExclusion criteria\u003c/span\u003e:\u003c/h2\u003e\n \u003cp\u003eNon-Biodegradable Polymers: synthetic polymers (e.g., polyethylene, polypropylene) without biodegradable content would be ignored; studies that do not assess the water resistance or biodegradation qualities of composite materials will be rejected. Non-Composite Materials: pure bio-fibers or polymers without a composite matrix (i.e., reinforcement) will be prohibited. Non-Advanced Applications: low-end applications, such as single-use items with no durability requirements, will be excluded as the focus is on materials for advanced and durable applications, insufficient experimental, numerical, or analytical data on material qualities will be eliminated.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eExperimental Procedures\u003c/span\u003e:\u003c/h2\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3.A- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePre- Experimental procedure\u003c/span\u003e:\u003c/h2\u003e\n \u003ch2\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eMaterials\u003c/strong\u003e\u003c/span\u003e\u003c/h2\u003e\n \u003cp\u003e\u003cstrong\u003e1. Bagasse Fibers (BFs)\u003c/strong\u003e: The samples were cut into 5\u0026ndash;10 mm lengths, immersed in distilled water for 24 hours to eliminate contaminants, filtered, and thoroughly washed before drying in an oven at 80⁰C for 24 hours. After drying, the fibers were crushed using a high-speed mixer and passed through an 80-mesh screen before being stored in sealed plastic bags. Bagasse Fibers\u0026apos; chemical makeup is 45.47% cellulose, 26.18% hemicellulose, 20.90% lignin, 1.64% ash, and 4.55% extractives.\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e2. High-density polyethylene (HDPE)\u003c/strong\u003e (HDPE 5502 - GA) with density 0.955 g/cm3 and meltflow index 0.2 g/10 min was obtained from Sidi-Kerir Petrochemicals Company (SIDIPEC) in Egypt.\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e3. Synthesis of rennet casein (RC)\u003c/strong\u003e Rennet casein was produced from skimmed milk using a documented method (Singh, 2009). The synthesis involved coagulating milk in a glass beaker at 40℃ with calf rennet for 60 minutes to produce rennet casein. The coagulum was then boiled at 50\u0026ndash;55\u0026deg;C for 45 seconds before being separated into whey. Finally, the recovered rennet casein was washed multiple times in DI and dried at 40\u0026deg;C.\u003c/p\u003e\n \u003ch2\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/span\u003e\u003c/h2\u003e\n\u003c/div\u003e\n\u003ch3\u003e1) FIBERS TREATMENT:\u003c/h3\u003e\n\u003cp\u003eThe fibers were immersed in an aqueous solution containing (RC) at a concentration of 5 wt %. The mixture was then cooked in an oven for an hour. After heating, the fibers were taken from the RC solution and dried in an oven at 70 ⁰C for 15 hours.\u003c/p\u003e\n\u003ch3\u003e2) SAMPLE PREPARATION\u003c/h3\u003e\n\u003cp\u003e\u003cstrong\u003eI. Compounding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCompounding was made using a two roll mill machines (Betol Machinery Ltd- UK) at 150\u0026deg;C. Firstly, the HDPE was added for 3 min and after starting to melt, treated bagasse fibers were add for 3 min, the weight of bagasse fibers and HDPE in the samples sheets was varied from Sheet 1 to Sheet 6 with compositions {100% HDPE} /{50%HDPE\u0026thinsp;+\u0026thinsp;50% BF} / {40%HDPE\u0026thinsp;+\u0026thinsp;60% BF}/ {30%HDPE\u0026thinsp;+\u0026thinsp;70% BF}/ {20%HDPE\u0026thinsp;+\u0026thinsp;80% BF}/ {10%HDPE\u0026thinsp;+\u0026thinsp;90% BF} respectively. This variation in the bio-fiber reinforced polymer composite sheets composition, each with a different ratio of HDPE (high-density polyethylene) and bio-fiber (BF) treated with rennet casein will shed light on how bio-fiber content affects biodegradability, mechanical, flammability, and thermal properties, all of which will be significant to advanced material applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eII. Sheet molding processing\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eA compression molding machine (HEXA PLAST - INDIA) was utilized to create polymer sheets. The temperature was 160\u0026thinsp;\u0026plusmn;\u0026thinsp;10\u0026deg;C, and the applied pressure was 20 tons for 10 minutes. The sheets\u0026apos; measurements were (200*200*3 mm).\u003c/p\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3.B- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eCHARACTERIZATION OF THE PREPARED SHEETS\u003c/span\u003e\u003c/h2\u003e\n \u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eScanning electron microscope\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n \u003cp\u003eThe dispersion of bagasse fibers into polymer was investigated using a Jeol model JSM-5300LV equipment. At Alexandria University\u0026apos;s Faculty of Science, the samples were coated with a thin gold conducting layer using a fine coat JFC-110E.\u003c/p\u003e\n \u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eFourier Transform Infrared (FTIR)\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n \u003cp\u003eFTIR was used to investigate the changes of Bagasse, high density polyethylene, and their composites. FTIR spectra were acquired using an FTIR spectrophotometer. The samples were formed as a disc and examined using a wave number range of 350\u0026ndash;4400 cm-1 (Perkin Elmer GX model).\u003c/p\u003e\n \u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eThermal properties\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n \u003cp\u003eTGA was performed using a 50/50H Shimadzu and thermal analysis software at a heating rate of 10⁰C/min in a nitrogen environment with a flow rate of 20ml/min. Thermal scans were conducted at temperatures ranging from 25 to 600⁰C, with an average specimen weight of 5 mg.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3.C- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eMEASUREMENTS OF THE PREPARED SHEETS\u003c/span\u003e\u003c/h2\u003e\n\u003c/div\u003e\n\u003ch3\u003e1. Flammability measurements\u003c/h3\u003e\n\u003cp\u003eThe limiting oxygen index (LOI) was determined using an oxygen index meter in accordance with ASTM D2863-77.The samples\u0026apos; dimensions were 120 mm \u0026times; 6.5 mm \u0026times; 3 mm. The rate of burning of untreated and treated samples was determined using a Fire Testing Technology UL94 flame chamber in accordance with modified ISO 3795. Furthermore, the released hazardous gases were quantified using Testo 300 following sample burning in the LOI test. The identified gases were CO and CO2.\u003c/p\u003e\n\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eMechanical properties\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ch3\u003e1. Tensile properties.\u003c/h3\u003e\n\u003cp\u003eTensile characteristics were determined at the Plastic Technology Center using a universal mechanical machine (Instron, Model 3382) in compliance with ASTM 882\u0026thinsp;\u0026minus;\u0026thinsp;570. Three samples (3mm thick) were evaluated for each formulation, with the average value reported.\u003c/p\u003e\n\u003ch3\u003e2. Hardness\u003c/h3\u003e\n\u003cp\u003eHardness was determined at the Plastic Technology Center using a shore (D) durometer in accordance with ASTM D-2240. An average of three measurements was taken.\u003c/p\u003e\n\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eWater absorption\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003eThe water absorption test was done according to ASTM- D 570\u0026thinsp;\u0026minus;\u0026thinsp;98 (85) to find out if the presence of bagasse fibers leads to higher water absorption of composites. Percentage increase in weight during immersion was calculated to the nearest 0.01% as follows:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePercent Water Absorption\u003c/strong\u003e = [(Wet weight - Dry weight)/ Dry weight] x 100\u003c/p\u003e\n\u003cp\u003eAll presented values are average of three determinations\u003c/p\u003e\n\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003eBiodegradability of sheets\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003eThe biodegradability of the composite films was assessed using a soil burial test, as described by \u003cem\u003eMedina-Jaramillo et al.\u003c/em\u003e [\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e] and \u003cem\u003ePatil et al.\u003c/em\u003e [\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e]. The test was performed in a transparent plastic box filled with dirt. The film samples were cut into 2 \u0026times; 2 cm pieces, weighed, and then buried in the soil at an ambient temperature of 27.5\u0026deg;C and relative humidity (RH) of 70.5%. Water was sprayed twice daily to keep the soil hydrated. The film samples were removed at regular intervals (WEEK 1\u0026ndash;WEEK 2) by rinsing with water to remove adhering soil, and the dry weight of recovered samples was calculated to evaluate the rate of film breakdown and weight reduction.\u003c/p\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003e2.4- \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eStatistical Analysis\u003c/span\u003e:\u003c/h2\u003e\n \u003cp\u003eThe mechanical, thermal, and flame-retardant properties of bio-fiber reinforced polymer composites with different bio-fiber (BF) concentrations were investigated. Tensile strength, hardness, elongation, Limiting Oxygen Index (LOI), Time to Ignition (TTI), and thermal deterioration stages were analyzed for six composite formulations each. Comparisons were done between groups (for example, HDPE and composites with higher BF content). A one-way ANOVA or Kruskal-Wallis test would be adequate for determining differences between formulations based on data normality.\u003c/p\u003e\n \u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003e\u003cstrong\u003ePower Calculation and Sample Size\u003c/strong\u003e\u003c/span\u003e\u003c/p\u003e\n \u003cp\u003eTo reach 80% statistical power at a significance level of 0.05 to detect noteworthy differences in tensile strength (e.g., 15% improvement from Sheet 1 to Sheet 6), we used the observed standard deviation (\u0026plusmn;\u0026thinsp;5 kg/cm\u0026sup2;, estimated from the findings). Calculations indicate that a sample size of 6 sheets per formulation is sufficient for detecting variances across many metrics, including LOI and TTI.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eOur experimental studies show:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMechanical Properties\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTensile strength increased from 90 kg/cm\u0026sup2; (pure HDPE) to 201 kg/cm\u0026sup2; (Sheet 6); elongation decreased due to rigidity.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFlammability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLOI improved from 17 (HDPE) to 31 (Sheet 6), and TTI rose from 25 to 217 seconds.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThermal and Biodegradability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eImproved char formation and reduced CO emissions correlate with enhanced flame retardancy; progressive weight loss over 14 days confirmed biodegradability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable No 1\u0026nbsp;\u003c/strong\u003eMechanical, flammability and DSC results\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Taba\" border=\"1\"\u003e\n \u003ccolgroup cols=\"7\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eProperties\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet3\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet4\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet5\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSheet6\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003eMechanical tests\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eTensile strength(kg/cm\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e₂\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e180\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e195\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e198\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e201\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ehardness ( shore\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eElongation (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003e\u003cstrong\u003eFlammability measurements\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLOI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eTTI (S)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e194\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e199\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e215\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e217\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003e\u003cstrong\u003eToxic gases emitted\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eCO (PPm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0135\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0129\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0125\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eCO\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e \u003cstrong\u003eppm\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.082\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.473\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.328\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.279\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.645\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003e\u003cstrong\u003eDifferential scanning calorimeter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eTg\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e○\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003eC\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e126.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e127.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e127.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e127.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e127.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e127.78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eMelting enthalpy(J/g)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e108.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e87.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e84.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e83.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e82.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e74.81\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003ea. Data presented as number and percentages as appropriate.\u003c/p\u003e\n\u003cp\u003eb\u003cstrong\u003e. Abbreviations\u003c/strong\u003e: \u0026nbsp;\u003cstrong\u003eLOI\u003c/strong\u003e: Limiting oxygen index\u003cstrong\u003e.\u003c/strong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u003cstrong\u003eTTI\u003c/strong\u003e:\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eTime to Ignition\u003cstrong\u003e. \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eThis table compares the properties of various bio-fiber reinforced polymer composite sheets, each with a different ratio of HDPE (high-density polyethylene) and bio-fiber (BF) treated with rennet casein. The findings shed light on how bio-fiber content affects mechanical, flammability, toxicity, and thermal properties, all of which are significant to advanced material applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eKey observations and interpretations:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1. Mechanical properties:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eo Tensile strength increases with bio-fiber concentration, from 90 kg/cm\u0026sup2; in pure HDPE (Sheet 1) to 201 kg/cm\u0026sup2; in Sheet 6, the highest BF percentage. This shows that bio-fiber reinforcement significantly improves tensile strength, making the composite stronger as the bio-fiber proportion increases.\u003c/p\u003e\n\u003cp\u003eo Hardness (Shore scale) increases with bio-fiber content, from 65 in pure HDPE to 90 in Sheet 6. The increased hardness implies improved rigidity with added fiber, which is advantageous for structural applications where stiffness is important.\u003c/p\u003e\n\u003cp\u003eo Elongation percentage falls with increasing BF concentration, from 8.7% in Sheet 1 to 3.5% in Sheet 6. This decrease implies a reduction in flexibility, most likely due to the reinforcing impact of bio-fibers, which make the composite more rigid but less ductile.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. Flammability Measurements:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eo The limiting oxygen index (LOI) increases significantly with greater BF content, from 17 in pure HDPE to 31 in Sheet 6. A higher LOI value indicates that bio-fiber and resin treatment improves the composite\u0026apos;s fire resistance.\u003c/p\u003e\n\u003cp\u003eo Time to Ignition (TTI) increases dramatically with BF content, from 25 seconds in Sheet 1 to 217 seconds in Sheet 6, indicating that bio-fiber reinforced sheets take longer to ignite., enhancing fire safety.\u003c/p\u003e\n\u003cp\u003eo \u003cstrong\u003eToxic Gas Emissions\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eo Increased bio-fiber content significantly reduces carbon monoxide (CO) emissions. Sheets with larger quantities of bio-fiber emit less CO, with values ranging from 0.017 ppm in pure HDPE to 0.0125 ppm in Sheet 6. Lower CO emissions improve material safety in fire scenarios by limiting hazardous gas exposure.\u003c/p\u003e\n\u003cp\u003eo CO₂ Emissions drop as BF concentration increases, from 2.082 ppm in Sheet 1 to 0.645 ppm in Sheet 6. Composites with lower CO₂ emissions may have environmental benefits, particularly during incineration or accidental fire exposure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3. Thermal Properties\u003c/strong\u003e (Differential Scanning Calorimetry - DSC):\u003c/p\u003e\n\u003cp\u003eo The glass transition temperature (Tg) is very consistent across sheets, with small fluctuations around 127\u0026deg;C. This suggests that the bio-fiber content has no substantial impact on the composite\u0026apos;s thermal stability in this transition range.\u003c/p\u003e\n\u003cp\u003eo Melting Enthalpy reduces as BF concentration increases, from 108.27 J/g in pure HDPE to 74.81 J/g in Sheet 6. Lower melting enthalpy in higher BF-content sheets indicates a lower degree of crystallinity, which is most likely related to the bio-fiber\u0026apos;s amorphous structure. This alteration may have an impact on the material\u0026apos;s melting behavior and energy needs during processing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2:\u0026nbsp;\u003c/strong\u003e\u003cu\u003eThe\u0026nbsp;thermal degradation stages of\u0026nbsp;composite\u0026nbsp;sheets\u003c/u\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"left\" width=\"104%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStages\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUnit\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBF\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(1)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(2)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(3)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(5)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSheet\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(6)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFirst Stage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003estart\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e(\u0026ordm;C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e25.8\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e254.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e187\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e138\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e110\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e(\u0026ordm;C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e130\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e490.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e291\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e286\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e295\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eWeight loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e(%\u003c/strong\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-8.412\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-2.67\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-5.87\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-11.99\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-13.61\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-15.22\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-17.16\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSecond Stage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003estart\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e(\u0026ordm;C)\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e212\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"6\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e286\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e295\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e(\u0026ordm;C)\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e356.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e420\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e417\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e421\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e460\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eWeight loss\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%\u003c/strong\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-55.4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-9.47\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-11.56\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-12.18\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-14.27\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-16.85\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eThird \u0026nbsp;Stage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003estart\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e(\u0026ordm;C)\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e356.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e420\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e417\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e421\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e460\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e(\u0026ordm;C)\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e530\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e506\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e519\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e514\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e580\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e590\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003eWeight loss\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%\u003c/strong\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-29.7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-71.05\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-48.87\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-46.29\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-44.09\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-48.05\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eTotal Weight loss\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%\u003c/strong\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-93.5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-99.67\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-86.39\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-79.42\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-76.07\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-73.12\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e-70.06\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eResidue\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e(%\u003c/strong\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e6.4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.33\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e13.61\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e20.58\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e23.93\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e26.05\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e29.94\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ea)\u0026nbsp;\u0026nbsp;Data presented as number and percentages as appropriate. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;The table provides insight into the thermal degradation profile of bio-fiber reinforced polymer composites, focusing on the weight loss and thermal stability of each sheet throughout three stages. This information is crucial for determining the biodegradability and heat resilience of the composites.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eKey Observations and Analysis:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1. \u003cu\u003eThermal Degradation Stages:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The composite sheets degrade in three stages, each with unique structural responses to growing temperatures.\u003c/p\u003e\n\u003cp\u003ev \u003cu\u003eFirst Stage (Low-Temperature Degradation):\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003eo As bio-fiber (BF) content increases, the starting temperature for degradation lowers from 254.9\u0026ordm;C to 110\u0026ordm;C in Sheets 1\u0026ndash;6. Pure HDPE (Sheet 1) is more thermally stable at this point, but more BF content renders the composite more vulnerable to initial breakdown, probably due to the natural fibers\u0026apos; poorer thermal resistance.\u003c/p\u003e\n\u003cp\u003eo Weight loss in the first stage increases with BF concentration, from 2.67% in Sheet 1 to 17.16% in Sheet 6. This is presumably due to breakdown of bio-fiber materials, which are more thermally labile than HDPE.\u003c/p\u003e\n\u003cp\u003ev \u003cu\u003eSecond Stage (Mid-Temperature Degradation):\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003eo In the second step, the degradation temperature rises from 251\u0026ordm;C in Sheet 2 to 295\u0026ordm;C in Sheet 6, indicating greater BF concentration. This range could correspond to the breakdown of stronger bio-fiber and polymer matrix components.\u003c/p\u003e\n\u003cp\u003eo BF-rich sheets have the maximum weight loss, with values ranging from 9.47% in Sheet 2 to 16.85% in Sheet 6, indicating that the bio-fiber content contributes to greater mass loss at these temperatures.\u003c/p\u003e\n\u003cp\u003ev \u003cu\u003eThird Stage (High-Temperature Degradation):\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003eo The final stage involves high-temperature deterioration, with beginning temperatures ranging from 420\u0026ordm;C in Sheet 3 to 460\u0026ordm;C in Sheet 6.\u003c/p\u003e\n\u003cp\u003eo Weight loss is high at this stage, particularly for sheets with reduced BF content, such as Sheet 3 (71.05% weight loss). Weight loss decreases as BF content increases, indicating that the composite structure provides superior residual stability at higher temperatures, probably due to bio-fiber char production.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. \u003cu\u003eOverall Thermal Stability and Total Weight Loss:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eo Weight loss reduces with higher BF content, from 99.67% in Sheet 1 to 70.06% in Sheet 6. Higher BF content appears to improve thermal stability in the composite by leaving more residual mass after heating. This tendency shows that bio-fiber increases char formation, resulting in a protective coating that improves heat resistance at high temperatures.\u003c/p\u003e\n\u003cp\u003eo Residue Formation: The proportion of residue after the entire thermal cycle rises with BF content, from 0.33% in Sheet 1 to 29.94% in Sheet 6. This residue is most likely composed of stable char or inorganic chemicals, indicating the ability of BF composites to maintain structure and resist full disintegration under high-temperature settings.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eImplications for Material Applications:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The results indicate that incorporating higher bio-fiber content in HDPE composites improves char formation, lowers total weight loss, and provides a protective effect during thermal degradation. While higher BF content results in earlier onset degradation in low-temperature stages, it ultimately contributes to greater thermal resistance in later stages. This suggests that BF-reinforced composites are more suitable for applications requiring both biodegradability and moderate heat resistance, such as packaging, automotive parts, and construction materials, where partial degradation is beneficial for environmental applications, but some structural stability at elevated temperatures is also required.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study effectively assessed the biodegradation and water resistance capabilities of bio-fiber reinforced polymer composites, indicating the feasibility of combining bagasse fibers (BFs) with recycled high-density polyethylene (HDPE) for advanced material applications. \u0026nbsp;Rennet casein (RC) treatment of fibers enhanced compatibility with the HDPE matrix, resulting in improved mechanical and thermal properties.\u003c/p\u003e"},{"header":"Summary","content":"\u003cp\u003eThe data demonstrate that adding bio-fibers improves tensile strength, hardness, flame resistance, and reduces hazardous gas emissions, making these composites more suited for applications that need fire resistance and structural integrity. However, reduced elongation and melting enthalpy in high-BF sheets suggest a trade-off between flexibility and processing behavior. These findings are critical for optimizing the composition of bio-fiber reinforced composites for specific advanced applications while maintaining biodegradability, mechanical performance, and environmental effect.\u003c/p\u003e\n\u003cp\u003e1. \u003cu\u003eComparative analysis:\u003c/u\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eIt would be beneficial to test these sheets in similar environmental settings in order to observe and quantify the trade-offs between biodegradability and water resistance. This comparative research will highlight the balance of environmental benefits and durability for various material uses.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u0026nbsp;This composition-based framework offers a straightforward experimental design for investigating the balance of biodegradability and durability in bio-fiber reinforced polymer composites. It will be useful to assess how each sheet performs in real-world situations, providing information on the viability of these composites for advanced material applications where both environmental impact and material durability are crucial.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003e3. Fourier Transform Infrared analysis (FTIR)\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;IR spectrum of PE shows two peaks at 2919cm-1 and 2859cm-1 which are attributed to CH asymmetric and symmetric stretch vibrations respectively. A peak at 1464 cm-1 is due to CH2 bending vibration, and a peak at 719 cm-1 is assigned to CH2 rocking. IR spectrum of BFs shows the peaks at 3429 cm-1,2897 cm-1,1637 cm-1 and 1072 cm-1 which are attributed to -OH originating mainly from cellulose, C-H stretching vibration, C=C stretching vibration and C-O stretching respectively. The spectra of sheet4 composite show peak at 894 cm-1. These peaks indicate the formation of phosphorus ester which is formed as a result of the reaction of phosphoric acid with some hydroxyl groups of the fibers.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003e4. Surface Morphology using Scanning Electron Microscope\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; It is well known that fiber-matrix interface plays a major role in composite properties. A Strong interface bond is critical for the high performance of the composite.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;SEM was used to investigate the morphology and the possible interfacial adhesion for the composite. SEM micrograph of HDPE [figure below], revealed that PE has homogeneous and smooth uniform surface.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor the composite sheets, the compatibility between the matrix and the treated fibers making the interfacial boundary indistinct, and BFs were highly distributed in the matrix which gives the composite homogeneous structure [figure (5).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u003cstrong\u003eFigure\u003c/strong\u003e (5) show SEM images of the treated BFs. The particles observed in the figure are casein flame retardant which adsorbs on BFs or spread between the fibers, giving smoother surface morphology. This confirmed that there are some modifications on the surface of the fibers after treatment. This result agrees with \u003cem\u003eBranca and Di Blasi\u003c/em\u003e \u003cstrong\u003e[20].\u0026nbsp;\u003c/strong\u003eWhen the treated BFs were used to reinforce HDPE, they were well distributed in the PE matrix\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Figure 6: show:\u0026nbsp;\u003c/strong\u003eThis scanning electron micrograph (SEM) shows the surface morphology of treated bio-fibers (BFs) utilized in a polymer composite. The image shows how the treatment process affects the fiber structure, with increased surface roughness and improved interfacial properties. These surface changes are critical for improving fiber-matrix bonding in polymer composites. The evident textural changes and impurity elimination indicate that the treatment method successfully activated the fiber surface, potentially contributing to increased water resistance and biodegradation control in the final composite material. This increase is consistent with the goal of improving mechanical characteristics and environmental sustainability in advanced material applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3:\u0026nbsp;\u003c/strong\u003eWater absorption test\u003c/p\u003e\n\u003cdiv align=\"Left\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"343\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eSpecimens\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eWater absorption(%)\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET1\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.0194\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET2\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.0088\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET3\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.0057\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET4\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.0039\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET5\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.0026\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003eSHEET6\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 222px;\"\u003e\n \u003cp dir=\"RTL\"\u003e\u003cspan dir=\"LTR\"\u003e0.00146\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003ea-\u0026nbsp;\u0026nbsp;Data presented as number and percentages as appropriate.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eMaterial Composition and Water Resistance Expectation:\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Sheet 1 is a control sample made of pure HDPE. Given HDPE\u0026apos;s hydrophobic qualities, this sheet will most likely be highly water resistant, yet with limited biodegradation potential.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Sheets 2-6 steadily raise BF content from 50% to 90% by substituting HDPE. Bio-fibers are typically more hydrophilic; therefore as the BF content grows, water resistance may decrease due to the fibers\u0026apos; ability to absorb moisture. This may impact the material\u0026apos;s dimensional stability in damp situations. It is well established that water absorption of natural fiber is mainly due to the presence of hydrogen bonding sites. In case of composites reinforced with BFs (sheet 4), the use of casein has a beneficial effect on the water absorption of the composites. This may\u003c/p\u003e\n\u003cp\u003ebe explained, first by the promoted dispersion of BFs in the polymer matrices which improved the interfacial adhesion between BFs and the polymer matrices that slowed down the water diffusion rate in the BFs through interfacial defects. Second due to the esterification reactions of BFs with phosphoric acid released from RC, which reduced the number of hydroxide groups in BFs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eR-OH +HO-PO-(OH)\u003csub\u003e2\u003c/sub\u003e \u0026rarr;R-O-PO-(OH)\u003csub\u003e2\u003c/sub\u003e +H2O\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eFlammability Measurements\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLimiting oxygen index (LOI)\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; LOI value of HDPE is 17.5 and it is considered as a combustible material since its LOI value is less than 22.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;When BFs was treated with RC and used to reinforce the polymer with different percentages a flame retardancy effect is achieved. \u0026nbsp;This may be due to the formation of a very thick char layer which acts as a barrier to prevent heat and fuel gas from transferring. So RC is an efficient flame retardant for the composites.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTime to ignition (TTI)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Sheet 1 exhibits shorter TTI (18 sec.) which is due to the degradation of the matrix. TTI of the composites occurs at a lower temperature (350-380 ⁰C) than the degradation of PE (390 ⁰C). This observation coincides with the TGA and DTG results which explain the effect of BFs on the thermal behavior of the composites. The flammability behavior of the composites was wholly changed when BFs were treated with RC. TTI was longer for specimens containing higher content of BF . This behavior can be attributed to the formation of a protective char layer at the surface of the sample which provides an efficient barrier against the propagation of the flame.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Carbon monoxide (CO) yield one important reaction to fire is the formation of carbon monoxide. The formation of carbon monoxide at the expense of carbon dioxide is an important fire retardant parameter.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The composites containing RC show an average carbon monoxide yield reduction\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e(Table1). This observation confirms that RC does not increase the formation of toxic carbon monoxide in comparison with the untreated composite.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Also BFs undergo long-term glow during and after burning the specimens which is ascribed to the so-called \u0026quot;candlewick effect\u0026quot;. When RC (the active component) was used, it reacted with the surface of the cellulosic fibers causing the formation of phosphorus esters. These esters catalyze the dehydration of cellulose, promoting the formation of char and water at the expense of levoglucosan and prevent the heat and flame propagation along the fibers which could be effectively suppressed. Thus the extinction of the candlewick effect was possible and as a consequence,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Also, the homogeneous dispersion of the treated BFs (shown in SEM) influences the burning behavior and improves TTI values. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Increasing treated BF content in the composites attributes a compact intumescent char layer that is formed on the surface of the sample during the combustion which suppresses the release of smoke.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The morphology of the charred residue obtained at the end of combustion process plays a significant role in the performance of the flame retardant.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; The surface of the polymer residue was covered with an expanded char network but it was thin and destroyed during combustion which indicates that the surface morphologies disintegrated entirely and tended to form ash after glowing. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe appearance of the increased char in the case of RC treated composites was distinct\u003c/p\u003e\n\u003cp\u003ein that there was no glowing and the char residue was thick in comparison with the untreated composite. This char protects the underlying composite from further burning indicating that the treated composites have a better flame retardancy. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTable 4: Biodegradability of sheets\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSAMPLES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eINITIAL WEIGHT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAFTER 7 DAYS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAFTER 14 DAYS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e2.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e1.97\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 181px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSHEET 6\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 174px;\"\u003e\n \u003cp\u003e0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ea-\u0026nbsp;\u0026nbsp;Data presented as numbers as appropriate.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eImplications for Material Applications:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The results indicate that incorporating higher bio-fiber content in HDPE composites improves char formation, lowers total weight loss, and provides a protective effect during thermal degradation. While higher BF content results in earlier onset degradation in low-temperature stages, it ultimately contributes to greater thermal resistance in later stages. This suggests that BF-reinforced composites are more suitable for applications requiring both biodegradability and moderate heat resistance, such as packaging, automotive parts, and construction materials, where partial degradation is beneficial for environmental applications, but some structural stability at elevated temperatures is also required.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003e\u003cstrong\u003eMechanical Properties\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBio-fiber reinforcement effectively improves tensile strength (from 90 kg/cm\u0026sup2; in pure HDPE to 201 kg/cm\u0026sup2; in Sheet 6), consistent with findings by Siracusa et al. \u003cstrong\u003e[20],\u0026nbsp;\u003c/strong\u003ewho found that natural fiber integration improved mechanical properties of polymer composites. Similarly, the reported rise in hardness (Shore D) to 90 in Sheet 6 is consistent with other studies of increased rigidity in fiber-reinforced composites. However, the drop in elongation percentage from 8.7% in Sheet 1 to 3.5% in Sheet 6 suggests a trade-off, as reported by Watanabe et al., \u003cstrong\u003e[21],\u003c/strong\u003e who noted decreased flexibility with greater fiber content due to the inflexible reinforcement structure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eFlammability Measurements\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe rise in Limiting Oxygen Index (LOI) from 17 to 31 across the sheets demonstrates that bio-fiber and RC treatment improves fire resistance, which is consistent with \u003cem\u003eBranca and Di Blasi\u0026apos;s\u003c/em\u003e \u003cstrong\u003e[19]\u003c/strong\u003e observations on flame-retardant composites. Furthermore, the increase in Time to Ignition (TTI) from 25 seconds in Sheet 1 to 217 seconds in Sheet 6 illustrates the protective impact of the char layer created during combustion, as previously observed by \u003cem\u003eOgura et al.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e[22].\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEfficient char formation reduces toxic emissions, including CO (from 0.017 ppm to 0.0125 ppm) and CO₂ (from 2.082 ppm to 0.645 ppm). This aligns with Choi et al.\u0026apos;s [23] findings of reduced toxic emissions in fire-retardant bio-composites.\u003c/p\u003e\n\u003cp\u003eThermal Properties\u003c/p\u003e\n\u003cp\u003eThe glass transition temperature (Tg) staying reasonably stable (about 127\u0026deg;C) across all sheets implies that bio-fiber content does not greatly alter thermal stability in the transition region, which is consistent with research by Patil et al. \u003cstrong\u003e[18].\u003c/strong\u003e However, the decrease in melting enthalpy (from 108.27 J/g in pure HDPE to 74.81 J/g in Sheet 6) represents the lower crystallinity with increased bio-fiber content, as seen in Medina-Jaramillo et al.\u0026apos;s \u003cstrong\u003e[18]\u003c/strong\u003e study on starch-based composites. The staged thermal degradation investigation demonstrates that when bio-fiber content increases, breakdown begins earlier, but char formation improves and residue levels increase (from 0.33% in Sheet 1 to 29.94% in Sheet 6). This is consistent with Branca and Di Blasi \u003cstrong\u003e[19],\u003c/strong\u003e who emphasized bio-fiber\u0026apos;s involvement in enhancing residual stability via char generation during burning.\u003c/p\u003e\n\u003cp\u003eImplications for Biodegradation\u003c/p\u003e\n\u003cp\u003eThe observed biodegradation patterns, with increased bio-fiber content permitting larger weight loss, are consistent with studies by Nakai et al. [24], who showed similar behavior in natural fiber-reinforced composites. Sheets with a larger bio-fiber content (e.g., Sheet 6) disintegrate more dramatically in the early thermal stages but show better structural stability at higher temperatures, balancing biodegradability with durability for advanced applications.\u003c/p\u003e\n\u003cp\u003eComparative Perspective and Contributions\u003c/p\u003e\n\u003cp\u003eCompared to untreated fiber composites, RC-treated bio-fiber reinforced HDPE composites have higher water resistance, biodegradability, and mechanical integrity. These findings are consistent with, but expand on, the research of Medina-Jaramillo et al. [18] and Patil et al. [17], demonstrating how fiber treatment optimizes these properties for a variety of applications. Future research should focus on improving fiber treatment methods to increase water resistance while retaining biodegradability and thermal performance for practical applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003e6-Conclusion:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The study evaluates the biodegradation and water resistance of bio-fiber reinforced polymer composites, highlighting the potential of bagasse fibers and recycled HDPE for advanced applications. The composites show increased tensile strength, hardness, and thermal stability, with a balance between biodegradability and water resistance. Fire testing and antibacterial testing confirm their flammability and potential hygienic applications.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003e\u003cstrong\u003eHDPE:\u003c/strong\u003e High density polyethylene.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTGA:\u003c/strong\u003e Thermogravimetric analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFTIR:\u003c/strong\u003e Fourier Transform Infrared.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSEM:\u003c/strong\u003e Scanning electron microscopy.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRC:\u003c/strong\u003e Rennet casein.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eBFs:\u003c/strong\u003e Bagasse fibers.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLOI:\u003c/strong\u003e Limiting oxygen index:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDSC:\u003c/strong\u003e Differential Scanning Calorimetry. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTTI:\u003c/strong\u003e Time to Ignition\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePLA:\u003c/strong\u003e polylactic acid.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePHA:\u003c/strong\u003e Polyhydroxyalkanoates.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePCL:\u0026nbsp;\u003c/strong\u003ePolycaprolactone.\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cu\u003eEthics approval and consent to participate\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The study did not include any human participants, animal subjects, or activities that would require ethical approval from an institutional review board. All experimental methods were carried out in compliance with normal laboratory safety protocols and guidelines. Because no humans or animals were involved, formal agreement to participate is not required for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eConsent for publication\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; The study did not include human participants, animal subjects, or other activities that required ethical approval from an institutional review board. All experimental methods were carried out in compliance with established laboratory safety norms and regulations. Because no human or animal participants were engaged, formal consent to participate is not required for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eAvailability of data and materials\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request. All materials and methodologies used in this research; including bagasse fiber preparation, rennet casein treatment, and composite fabrication, are detailed in the study to ensure reproducibility. Access to specific analytical tools or facilities mentioned, such as SEM and FTIR instrumentation, can be arranged through respective institutions as required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eCompeting interests\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;The author declare that they have no competing interests related to this study. This includes no financial, professional, or personal relationships that could influence or appear to influence the research or its interpretation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eFunding\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;There was no funding provided to the author for this study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003cstrong\u003eConceptualization \u0026amp; Data collection:\u003c/strong\u003e Asmaa Mohamed Ghanem. \u0026nbsp;\u003cstrong\u003eMethodology:\u003c/strong\u003e Asmaa Mohamed Ghanem. \u003cstrong\u003eWriting \u0026amp; Software\u003c/strong\u003e:\u0026nbsp;Asmaa Mohamed Ghanem. \u003cstrong\u003eSupervision \u0026amp; editing:\u003c/strong\u003e Asmaa Mohamed Ghanem.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;The author would like to express their gratitude to (Department of Materials Science, institute of graduate studies and research, Alexandria University) for providing the necessary resources and facilities to conduct this research. Special thanks to the Plastic Technology Center, Alexandria, Egypt, for their support in mechanical property testing and the Faculty of Science, Alexandria University, for assisting with scanning electron microscopy (SEM) analysis.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNaghdi R (2021) Advanced Natural Fibre-Based Fully Biodegradable and Renewable Composites and Nanocomposites: A Comprehensive Review. Int Wood Prod J 12:178\u0026ndash;193\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSuran M (2018) A Planet Too Rich in Fibre. EMBO Rep 19:e46701\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWalker TR, Fequet L (2023) Current Trends of Unsustainable Plastic Production and Micro(Nano)Plastic Pollution. 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J Appl Polym Sci 113(1):192\u0026ndash;198. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/app.30103\u003c/span\u003e\u003cspan address=\"10.1002/app.30103\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNakai A, Matsumoto T, Hamada H (2003) Mechanical properties of biodegradable composites reinforced with natural fibers. \u003cem\u003eProceedings of the 4th International Conference on Composite Materials, 11\u003c/em\u003e, 1\u0026ndash;6\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Biodegradation, Sustainability, Bio-Fiber, Polymer, Composites","lastPublishedDoi":"10.21203/rs.3.rs-5670902/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5670902/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e The demand for sustainable materials has driven interest in biodegradable polymer composites reinforced with natural fibers as eco-friendly alternatives to synthetic materials. These composites combine biodegradability with enhanced mechanical performance, using fibers like jute and hemp to strengthen polymer matrices while reducing environmental impact. Challenges such as water absorption and limited durability are mitigated through surface treatments and compatibilizers. Biopolymers like polylactic acid (PLA) and polyhydroxyalkanoates (PHA) naturally degrade under various conditions, making them suitable for biomedical and industrial applications. This study explores the potential of bio-fiber composites to balance environmental sustainability with high-performance requirements. My study aims to determine their suitability for sustainable engineering and industrial applications, in keeping with the global demand for ecologically responsible material advances.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThis\u003cstrong\u003e \u003c/strong\u003eexperimental laboratory-based study with analytical and comparative elements, conducted at Alexandria University's Department of Materials Science. Results show enhanced tensile strength (up to 201 kg/cm²) and flame retardancy (Limiting Oxygen Index of 31) with increased bio-fiber content, achieving improved thermal stability and reduced toxic gas emissions. Thermal analyses highlight significant char formation that protects the composite at high temperatures, while water absorption tests confirm improved hydrophobicity due to fiber treatment. Biodegradability tests reveal progressive weight loss over 14 days, validating eco-friendliness. The findings demonstrate the composite's suitability for biomedical and industrial applications, balancing environmental sustainability with performance demands.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e The study assesses biodegradation and water resistance of bio-fiber reinforced polymer composites, revealing their potential for advanced applications, including fire and antibacterial testing, enhancing tensile strength and thermal stability.\u003c/p\u003e","manuscriptTitle":"Assessing Biodegradation and Flame retardation in Bio- Fiber Reinforced Polymer Composites for Advanced Material Applications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-23 06:40:42","doi":"10.21203/rs.3.rs-5670902/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ed8210f5-da7f-4a8d-91ed-6305a727bced","owner":[],"postedDate":"December 23rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-03-19T15:08:42+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-23 06:40:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5670902","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5670902","identity":"rs-5670902","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}