Preparation of novel CO 2 copolymer diol and its application on waterborne polyurethane

Preparation of novel CO 2 copolymer diol and its application on waterborne polyurethane | 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 Preparation of novel CO 2 copolymer diol and its application on waterborne polyurethane Wenqi Xian, Maoyi He, Rui Zheng, Zhu Liu, Ming Lu, Yuehuan Chu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5525654/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 26 Feb, 2025 Read the published version in Journal of Polymer Research → Version 1 posted 5 You are reading this latest preprint version Abstract CO 2 copolymer diol (PPCD) with superior transparency is an indispensable raw material for the polyurethane polymers, especially for water-based polyurethane coatings. However, commercial PPCD is generally opaque. In this work, A novel sustainable, colorless and transparent PPCD was prepared by using carbon dioxide (CO 2 ) and propylene oxide (PO) as raw materials. Its basic structure was tested and verified by Fourier transform-infrared (FT-IR) and proton nuclear magnetic resonance ( 1 H NMR) spectroscopy. Appropriate increase CO 2 content did not obviously reduce the transparency and thermal stability of PPCD and the optimum value was 29.1 wt.%. Furthermore, the waterborne polyurethane (WPU) was successfully synthesized by prepolymer method with poly(1,4-butylene adipate) (PBA), polypropylene glycol (PPG) or prepared PPCD as the soft segment, respectively. With the increase of CO 2 content, the thermodynamic property of WPU was significantly improved. When CO 2 content increased from 23.50 wt.% to 31.50 wt.%, the tensile strength increased from 23.27 MPa to 64.63 MPa and the elongation at break decreased from 750.85–520.37%, accompanied by the glass-transition temperature increased from − 49.7 ℃ to -34.5 ℃. In addition, the WPU prepared by PPCD was also found to have better tensile strength, transparency and storage stability than that prepared by PBA and PPG. A new inspiration was provided to develop high-transparent CO 2 based water-based polyurethane coatings. CO2 polymerization CO2 copolymer diol Waterborne polyurethane Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Introduction Carbon dioxide (CO 2 ), as a widely existing gas in nature, is also the exhaust gas emitted by human industrial production. The massive emission of carbon dioxide has broken the balance of the carbon cycle in nature, and has not been effectively recycled for a long time, which is the main reason for climate warming [ 1 – 2 ] . At the same time, CO 2 , as a rich source of carbon resources, is a potential raw material for chemical synthesis [ 3 – 4 ] . The resource utilization of carbon dioxide [ 5 – 7 ] can not only accelerate the realization of the goal of “carbon peaking and carbon neutrality”, but also synthesize polymer materials. The development of artificial carbon cycle can reduce the use of traditional petroleum-based materials and reduce dependence on non-renewable petroleum resources, which has a wide range of social, economic and environmental values [ 8 – 11 ] . Therefore, the study of carbon dioxide polymerization and the preparation of materials with practical application value are more and more concerned by researchers. In recent years, great progress has been made in the preparation of polymer materials with CO 2 , PO, EO and other compounds and this method of synthesizing organic polymers makes great use of CO 2 gas. Among them, CO 2 copolymer diol (PPCD) is prepared by ring-opening polymerization with CO 2 and PO as the main raw materials, which can be used as a new raw material for the synthesis of polyurethane, and then realize the resource use of carbon dioxide materials. As an inert gas, carbon dioxide is extremely stable in thermodynamics. It is not reactive under general reaction conditions, so it is difficult to react with other reactants. In general, specific catalysts need to be added to break the carbon and oxygen bond for reaction under certain conditions of temperature and pressure. Therefore, it is extremely important to study the catalyst system and select the transformation path [ 12 , 13 ] . At present, the research on the polymerization of carbon dioxide and epoxide mainly focuses on the development of efficient catalyst system. In 1969, Professor Shohei Inoue developed the diethyl zinc-water catalytic system (ZnEt 2 -H 2 O) to prepare carbon dioxide-based polymer by ring-opening copolymerization of CO 2 and PO. The preparation of high molecular weight resins by the polymerization of carbon dioxide has attracted more and more attention of researchers worldwide [ 14 – 15 ] . Then, a large number of basic researches have been carried out worldwide, and various catalyst systems for the preparation of carbon dioxid-based polymers have been developed, including organic zinc, salen, rare earth and bimetallic catalysts [ 16 – 20 ] . The catalytic efficiency of various systems is different with their own characteristics, among which the organic zinc catalyst has been studied most deeply, while the bimetallic catalyst (DMC) has been successfully applied in the industrial production of CO 2 copolymer diol. CO 2 copolymer diol, with reactable hydroxyl terminal structure at both ends of the molecular chain, can be used as raw materials to prepare polyurethane resin [ 21 – 24 ] , replacing the traditional petroleum based polyols, which just satisfied the needs of the polyurethane field. It has become a new research field, and will continue to develop and explore its practical value in the future. In this paper, CO 2 and PO are used as raw materials to prepare colorless and water permeable PPCD with different CO 2 content through the improvement of the synthesis process, which solves the problem that there are too many residual metal catalysts of CO 2 copolymers and their colors are too dark and opaque, which limits their application in many fields. Then, We tried to use PPCD with high transparency to prepare waterborne polyurethane materials, and explore the influence of carbon dioxide content on the properties of waterborne polyurethane in detail. The combination of CO 2 polymer and waterborne polyurethane not only satisfies the real resource utilization of carbon dioxide materials, but also provides a new direction for the development of waterborne polyurethane industry. Therefore, the study has great practical significance. Materials and Methods Main materials The bimetallic catalyst (DMC,industrial grade) was supplied by Guangdong Dazhi Environmental Protection Technology Co., Ltd. (China). Carbon dioxide (CO 2 > 99.99%) was purchased from Guangzhou Shiyuan Gas Co., Ltd.(China). Epoxy propane (PO, industrial grade) was provided by Tianjin Dagu Chemical Plant, and it was soaked with 4A molecular sieve before use. Isophorone diisocyanate (IPDI, industrial grade) was purchased from Wanhua Chemical Group Co., Ltd. (China). 2,2-Dimethylol propionic acid (DMPA, AR), and stannous octoate (T9, AR) were purchased from Tianjin Damao Chemical Reagent Factory. Triethylamine (TEA, AR), acetone (AC, AR), ethylenediamine (EDA, AR), were obtained from from Aladdin Company. Preparation of CO copolymer diols and CO based waterborne polyurethane First, carbon dioxide (CO 2 ) and Epoxy propane (PO) were charged in a dry high pressure flask with a mechanical stirrer and catalyzed by bimetallic catalyst (DMC). The mixture was reacted at 60°C under a certain pressure until the solid content of the solid content of the polymer reaches more than 97%, and then the heating is stopped. When the prepolymer is cooled to 40°C, stop stirring to obtain the intermediate product. After the process of removing by-products (PC) and catalyst, the CO 2 copolymer diols is obtained. The reaction scheme for the synthesis of CO 2 copolymer diol is illustrated in Fig. 1 . Preparation of waterborne polyurethane emulsion The waterborne polyurethane was synthesized by traditional prepolymer method. First, PPCD, IPDI, DMPA were charged into a 1000 mL three-necked flask equipped with an electric stirrer under nitrogen atmosphere. T-9 (0.2 wt.% of PPCD) was added into the mixture, and the reaction mixture was heated up to 100°C to react for about 4 h until the theoretical -NCO content of the prepolymer was reached. Then, the mixture was cooled to about 40°C and add appropriate acetone to reduce the viscosity. The neutralizing agent (TEA) was added into the mixture for about 5 min. After the neutralization, the prepolymer was poured into cold deionized water (approximately 15°C) and stirred vigorously at approximately 3000 r/min until the prepolymer is completely dispersed. After that, EDA(dilute with ice water to 30 wt.%)was added to extend the final backbones and the emulsion was slowly heated up to 75°C for 2 h until the theoretical -NCO content of the system was complete reaction. Finally, PPCD-WPU emulsion was obtained after removing the solvent by vacuum decompression. The reactant proportion is listed in Table 1. The reaction scheme for the synthesis of WPUs is illustrated in Fig. 2 . Table.1 Formulations of waterborne polyurethane Sample designation PPCD/PBA/PPG(g) IPDI/DMPA/TEA/EDA/H 2 O(g) PPCD-601-WPU 100 80/6/4.5/2.4/260 PPCD-611-WPU 100 45/5/3.7/1.3/260 PPCD-621-WPU 100 35/5.7/4.3/1.3/260 PPCD-632-WPU 100 35/5.8/4.3/1.6/260 PBA-2000-WPU 100 35/5.7/4.3/1.3/260 PPG-2000-WPU 100 35/5.7/4.3/1.3/260 Characterizations The viscosity and hydroxyl value of the polymer was tested in accordance with the enterprise standard Q/DZHB 10-2019 of Guangdong Dazhi Technology Co., LTD. The infrared absorption structure of the polymer was analyzed by Fourier Transform Infrared (FT-IR), with an appropriate amount of polymer resin uniformly tested on KBr salt sheets, and it was ftir analyzed in the range from 500 cm − 1 to 4000 cm − 1 . The chemical structure of polymer was tested by 1 H NMR instrument at room temperature with 16 scanning times. Take appropriate amount of sample resin dissolved reagent grade deuterium chloroform, the concentration is about 3% ~ 5%, the sample is placed in a nuclear magnetic tube with a height of about 4 cm ~ 5 cm, the CO 2 content of polymer is calculated according to the hydrogen displacement in the nuclear magnetic spectra. The transparency of appearance was tested by UV-vis spectrophotometer in accordance with ASTM D 1003-13. Take appropriate amount of sample resin into the colorimetric sample dish, after blank contrast, test the transmittance of resin. Thermogravimetric analyzer (TGA) was used to test the thermal decomposition performance. In nitrogen atmosphere, the flow rate was 20 mL/min, and the speed was set at 10 ℃/min. Polymer samples were tested from 25 ℃ to 500 ℃. Differential scanning calorimeter (DSC) was used to test T g of PPCD resin, and nitrogen was used to cool the test with a flow rate of 50 mL/min. The sample test range was from − 50 ℃ to room temperature, and the sample test speed was set to 10 ℃/min. The tensile properties of WPU films was tested by electronic testing machine. The film prepared in advance was tested according to GB/T1040-92 standard. The spline was dumbbell type sample, the test rate was 200 mm/min, and the original distance was 25 mm. Results and Discussion Infrared spectrum of prepared PPCD and PPCD/PBA/PPG-WPU The infrared absorption spectra of the main structures of CO 2 copolymer diol are shown in Fig. 2 – 5 (a). The most left wavelength is about 3500 cm − 1 and there is an obvious wide absorption peak, which is the peak of hydroxyl terminal (-OH) in the structure of PPCD. The peaks in the range of 1780 cm − 1 and 785 cm − 1 are due to the absorption of propylene carbonate (PC) carbonyl (C = O), a by-product generated in the synthesis of PPCD. The peaks at 1740 cm − 1 and 1262 cm − 1 are formed by the (-C = O) bond and (-C-O-) bond in carbonate bond. The peaks at 1378 cm − 1 and 1067 cm − 1 are attributed to the -C-O-C- structure of the polyether segment in the PPCD molecular chain. The infrared spectrum comprehensively reflects the characteristic absorption peaks of the main structures of PPCD. The infrared spectra of PPCD-WPU film were analyzed in Fig. 2 – 5 (b). The positions of absorption peaks of main structures were given, and compared with traditional waterborne polyurethane. In the PPCD-WPU infrared absorption spectrum, the peaks at 1740 cm − 1 and 1262 cm − 1 are attributed to the characteristic absorption peaks of (-C = O) and (-C-O-) bonds in the carbonate bond in the PPCD molecular chain. The PPCD molecular chain has both carbonate bond and polyether structure, and the characteristic peak is in the range of 1067 cm − 1 . Similarly, in the PBA-WPU absorption spectrum, the peak at 1728 cm − 1 is caused by the (-O-C = O-) group in the polyester structure. In the infrared absorption spectrum of PPG-WPU, the peak at 1100 cm − 1 was caused by ether bond (-COC-). There are absorption peaks at 1560 cm − 1 , which are vibration absorption peaks of carboxylic acid in DMPA on the main chain structure. The results showed that the hydrophilic monomers reacted on the molecular backbone of waterborne polyurethane with different soft segment structures. 1 H NMR spectra of prepared PPCD As shown in Fig. 4 (a, b), the characteristic molecular structure of PPCD with different CO 2 content can be characterized by 1 H NMR hydrogen spectrum. The carbon dioxide content in molecular chain segment can be calculated according to the peak area. As can be seen from 1 H NMR (400 MHz, CDCl 3 ), CDCl 3 : δ (ppm) = 7.28 (H, =CH 2 ), 4.95 (1, H, -CH=), 4.85 (2, 1H, -CH=), 4.6 (3, 5, 2H, -CH 2 -), 3.9 ~ 4.3 (4, 2H, -CH 2 -), 3.3 ~ 3.8 (6, 2H, -CH 2 -, 7, H, -CH=), 1.55 (8, 3H, -CH 3 ), 1.2 ~ 1.4 (9, 3H, - CH 3 ), 1.0 ~ 1.21 (10, 11, 3H, -CH 3 ). Table 2 shows the basic physical and chemical properties of PPCD with different carbon dioxide contents. The carbon dioxide content, viscosity, hydroxyl value and other basic properties of PPCD were investigated. The content of carbon dioxide basically remained between 23% and 32%, which was greatly related to the actual polymerization conditions. The viscosity of PPCD-632 is the highest, which is mainly related to the content of carbon dioxide in the molecular chain, namely the carbonate group. High carbon dioxide content means the increase of the carbonate group in the molecular chain, the increase of intermolecular interaction force, easier to form hydrogen bonds and greater molecular cohesion. Table 2 Basic physical and chemica parameters of PPCD Sample CO 2 content (%) Hydroxyl value(mgKOH/g) Viscosity(mPa⋅s) functionality PPCD-601 31.5 ± 1 224 ± 2 5000 ± 500 2 PPCD-611 30.6 ± 1 112 ± 2 5000 ± 500 2 PPCD-621 26.4 ± 1 56 ± 2 6000 ± 1000 2 PPCD-631 23.5 ± 1 37 ± 2 4000 ± 500 2 PPCD-632 29.1 ± 1 37 ± 2 10000 ± 1000 2 Note: Hydroxyl value was titrated by enterprise standard Q/DZHB 10-2019, CO 2 content was calculated by 1 H NMR, and viscosity was measured at 40 ℃. Appearance of PPCD Transparency is an important indicator of the appearance of the polymer, for applications in optical components, transparent medical material and UV curing coating and decoration of cosmetic requirements such as high field has an important influence, transparent resin has application prospect in many industries. The transparency of PPCD material was analyzed by UV-vis, as shown in Fig. 5 . The results indicated that the overall transmittance of PPCD reached more than 50% in the visible wavelength (380 nm ~ 780 nm), and the transparency of PPCD-621, 631 and 632 resins is even higher than 90%, which means that PPCD can be used to prepare high transparency materials, and may be applied in the fields of light curing, 3D printing materials, optical lenses and display screens. However, with the increase of carbon dioxide content and the increase of carbonate structure, the UV-vis transmittance of resin decreased, indicating that carbon dioxide content in molecular structure may affect the transparency of resin. The ether bond and carbonate structure exist simultaneously in the molecular chain segment. The refractive index of the two structures is different to light, and the higher carbon dioxide content will cause the UV- vis transmittance of the resin to decrease. Thermal properties of PPCD with different CO content PPCD mainly have carbonate bond, ether bond and side methyl structure, according to the different synthesis process and formula, the content of various groups in the molecular structure will be different, so when investigating the heat resistance of polyols, there are differences in thermal decomposition temperature. Thermogrgravity analysis (TGA) of PPCD-601, PPCD-611, PPCD-621, PPCD-631 and PPCD-632 was compared to explore the thermal degradation process. As shown in Fig. 6 and Table 3. On the whole, only a small amount of mass loss before 200 ℃, resin can remain stable, trace mass loss is likely to be unvolatile water or by-products. With the increase of temperature, the mass loss of resin began to increase. The mass loss temperatures of 5 wt .%, 10 wt .% and 50 wt .% of the resin were compared, respectively. As shown in Table 3, the 5 wt .% mass loss temperature of PPCD-632 was 240.1 ℃, while the 5 wt .% mass loss temperature of PPCD-601 was 205.8 ℃. In the process of 5% ~ 10% mass loss, the curve decreases obviously. The mass loss at this stage is mainly caused by the volatilization of by-products in the polymer. A small amount of propylene carbonate (PC) monomer is generated during the synthesis of PPCD. Therefore, the initial mass loss of thermal analysis is mainly caused by the volatilization of by-products. At 50 wt .% mass loss of the polymer, the temperature range of the five samples was 314.5 ℃ to 321.1 ℃, with little difference in temperature range. It shows that the material has good heat resistance. Table.3 Thermogravimetric temperature of PPCD Sample T 5 wt.% (°C) T 10 wt.% (°C) T 50 wt.% (°C) ) PPCD-601 205.8 246.3 314.5 PPCD-611 215.1 252.1 315.7 PPCD-621 221.3 264.1 320.5 PPCD-631 232.2 268.5 321.6 PPCD-632 240.1 270.5 319.1 Glass transition temperature of PPCD with different CO 2 content Glass transition temperature ( T g) of polymers is an inherent property of materials, closely related to molecular movement and structure, and the level of T g has a great influence on the application of materials. Differential scanning calorimetry (DSC) was used to analyze the prepared PPCD to explore the influence of different carbon dioxide content on the glass transition temperature of the polymer. As can be seen from Fig. 7 , different carbon dioxide content in the polymer has a great influence on the glass transition temperature of the prepared PPCD. Due to the high content of carbonate bond in the molecular structure of PPCD-601 and PPCD-611, the T g of the polymer also increases, reaching the region of -34.5 ℃ and − 35.1 ℃. And as the carbon dioxide content in the polymer decreases, the T g of the polymer moves to a lower temperature. The main reason affecting the glass ring transition temperature is that the introduction of synthetic carbonate groups in the polymer with increased carbon dioxide enhances the polarity of PPCD molecular chain segment, and the flexibility and movement of molecular chain segment are limited, thus increasing the glass transition temperature. The high glass transition temperature of PPCD-601 and PPCD-611 is due to the high carbon dioxide content of the synthetic polymer molecular chain up to 31.5%. The glass transition temperature of PPCD-631 is the lowest, reaching − 49.7 ℃ and the carbon dioxide content of the polymer is low, only about 23%, the number of polar groups on the molecular chain is relatively small, and the structural flexibility of the molecular chain is improved. The T g of the polymer is obviously affected by the CO 2 content in the structure, so the performance of the polymer can be controlled according to the actual situation. Mechanical properties of PPCD-WPU PPCD was used as a raw material to prepare waterborne polyurethane resin. It is an effective way to judge the mechanical properties of the noval waterborne polyurethane resin by investigating its basic tensile properties, as shown in Fig. 8 . Table 4 shows the relationship between stress and strain of PPCD-WPU film. It can be found that the mechanical properties of PPCD-WPU are affected by the CO 2 content in the soft section. When the CO 2 content of PPCD molecular chain reaches about 31.5%, the tensile strength of the prepared PPCD 601-WPU film reaches the highest, while the elongation at break is the lowest. When the CO 2 content in PPCD molecular chain is 26.4%, the tensile strength of the prepared PPCD 631-WPU film is 23.27 MPa, which is the lowest value among the five samples. At this time, the elongation at break is 750.85%, which is in a high range. The results showed that with the increase of CO 2 content in the molecular structure of PPCD, the mechanical strength of PPCD-WPU was enhanced, but the elongation of PPCD-WPU was affected to some extent. PPCD molecular structure contains strong polar carbonate groups and ether bond structure with good flexibility. By regulating their relative contents in molecular structure, PPCD-WPU can be prepared to satisfy the needs of practical applications. Table.4 Tensile strength and elongation at break of PPCD-WPU Sample CO 2 content of soft segment(%) σ(MPa) ε (%) PPCD-601-WPU 31.5 ± 2 34.63 520.37 PPCD-611-WPU 30.6 ± 2 32.15 565.28 PPCD-632-WPU 29.1 ± 2 31.12 723.52 PPCD-621-WPU 26.4 ± 2 27.41 819.45 PPCD-631-WPU 23.5 ± 2 23.27 750.85 Table.5 Tensile strength and elongation at break of PPCD-WPU Sample M n(g/mol) σ(MPa) ε (%) PPCD-621-WPU 2000 27.41 819.45 PBA-2000-WPU 2000 30.35 805.81 PPG-2000-WPU 2000 11.24 1232.48 In order to compare the performance of PPCD-WPU, polyester waterborne polyurethane (PBA-WPU) and polyether waterborne polyurethane (PPG-WPU) were selected for comparison with the mechanical properties of PPCD-621-WPU. As shown in Fig. 9 and Table 5, it can be found that the tensile platform of PCD-621-WPU film is significantly higher than that of the other two traditional waterborne polyurethanes, proving that PPCD-621-WPU has strong partial plasticity. The stress and tension of PBA-WPU reaches 30.35 MPa, while that of PPG-WPU film is 11.24 MPa. The elongation is the longest, reaching 1232.48%. The tensile strength of PPCD-621-WPU film has reached the performance of polyester, and the elongation can also be maintained well. This has a great relationship with the molecular structure of PPCD. There are a large number of polar groups of carbonate in the molecular structure and ether bonds in the structure, which has both strength and flexibility. The waterborne polyurethane prepared from PPCD is a new material with excellent performance. Conclusions A series of CO 2 copolymer diol (PPCD) were prepared with carbon dioxide (CO 2 ) and epoxide (PO). The basic structure and physical and chemical properties of PPCD were characterized by modern testing methods. Firstly, the molecular structure of PPCD was analyzed by FT-IR. The characteristic absorption peaks of carbonate bond and ether bond in polymer structure were obtained.The chemical shift of hydrogen on the polymer structure was analyzed by 1 H NMR, and the CO 2 content of PPCD was calculated to be between 23.5% and 31.5% by absorption peak area. The appearance of PPCD was characterized by ultraviolet visible spectroscopy (UV-vis). The overall visible light transmittance of PPCD was more than 90% in the range of UV-visible light (80 nm ~ 3 nm), which can be used to prepare high transparency materials. Thermogravimetric analysis (TGA) was used to investigate the thermal stability of PPCD. The significant mass loss occurred only when the temperature was above 200 ℃. When the mass loss reaches 50%, the decomposition temperature is between 314.5 ℃ and 321.1 ℃, indicating that PPCD polymer has good thermal stability. Differential scanning calorimetric analysis (DSC) was used to analyze the PPCD. It was found that the glass transition temperature of the polymer was closely related to the carbon dioxide content in the polymer. PPCD-601 with CO 2 content of 31.5% has a T g of -34.5°C, while PPCD-631 with carbon CO 2 content of 23.5% has a T g of -49.7 ℃, which is obviously higher. Then, PPCD was used as raw material to prepare waterborne polyurethane (PPCD-WPU). The mechanical properties of PPCD-WPU with different CO 2 content were compared by mechanical property test. It was found that WPU with high CO 2 content in soft segment had great influence on tensile strength, which was mainly caused by the joint action of carbonate bond and ether bond in the molecular structure of soft segment. At the same time, compared with polyester and polyether waterborne polyurethane, PPCD-WPU has high strength and flexibility, and the molecular structure of PPCD is adjustable. It is expected to provide a new raw material with economic and social value for the polyurethane industry in the future. Declarations Conflict of interest We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted. Acknowledgment This work was supported by the Doctoral Research Initiation Project of Huizhou University (Grant No. 15602230032 and 15602245011) and the Undergraduate Innovation and Entrepreneurship Training Program (Grant No.240170004010). References Duan Wenjuan. International Energy Agency released a report: global carbon emissions hit a record high last year [J]. Earth, 2019, 05: 22–23. Super M, Beckman E J. Copolymerization of CO 2 and cyclohexene oxide[J]. Macromolecular Symposia, 2015, 127(1): 89–108. Langanke, A. Wolf, J. Hofmann. Carbon dioxide (CO 2 ) as sustainable feedstock for polyurethane production[J]. Green Chemistry, 2014, 16(4): 1865–1870. Stephan Klaus, Maximilian W. Lehenmeier, Carly E. Anderson. 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Cite Share Download PDF Status: Published Journal Publication published 26 Feb, 2025 Read the published version in Journal of Polymer Research → Version 1 posted Reviewers agreed at journal 18 Dec, 2024 Reviewers invited by journal 18 Dec, 2024 Editor invited by journal 28 Nov, 2024 Editor assigned by journal 27 Nov, 2024 First submitted to journal 26 Nov, 2024 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-5525654","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":391842176,"identity":"f7ea2a72-9817-4917-a13d-40e0eb0f8968","order_by":0,"name":"Wenqi Xian","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0ElEQVRIiWNgGAWjYBACNvb24z8+/rHhYWxmPkCcFj6eMwmSMxvSZJjb2RKI0yInkWAgzdlw2Ia9n8eASIfxHEgwZtyRxsPbzPPxxhsGOzndBkJa2BsPJBeeseGRbObdbDmHIdnY7AARthyewZbGY9jMu02ah+FA4jaCWiQSDJt52A7z2B/meUa0FmNm3rbDwEDmYSNSC8+ZNMYZZ9KAWtiMLecYEOEX+fb2YwwfKmzsGfsPP7zxpsJOjqAWFCBBbNQgayFVxygYBaNgFIwIAACBzj604VRgYQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-5019-3056","institution":"Huizhou University","correspondingAuthor":true,"prefix":"","firstName":"Wenqi","middleName":"","lastName":"Xian","suffix":""},{"id":391842177,"identity":"1518c133-9bdd-42b8-bb53-3b91d97f05b1","order_by":1,"name":"Maoyi He","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Maoyi","middleName":"","lastName":"He","suffix":""},{"id":391842178,"identity":"e4478cbc-dba3-4805-9934-e5c6dec6988d","order_by":2,"name":"Rui Zheng","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Rui","middleName":"","lastName":"Zheng","suffix":""},{"id":391842179,"identity":"f9705f4f-4698-4101-b03b-59f84868e3f9","order_by":3,"name":"Zhu Liu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Zhu","middleName":"","lastName":"Liu","suffix":""},{"id":391842180,"identity":"5c535665-d0f5-40f8-9da0-df9654ed1eea","order_by":4,"name":"Ming Lu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ming","middleName":"","lastName":"Lu","suffix":""},{"id":391842181,"identity":"5320e727-bdc5-4a7d-a22a-e1da7e73b199","order_by":5,"name":"Yuehuan Chu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yuehuan","middleName":"","lastName":"Chu","suffix":""},{"id":391842182,"identity":"fd86c7f1-25d6-42ba-9b99-1284bc029493","order_by":6,"name":"Hao Cao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Cao","suffix":""}],"badges":[],"createdAt":"2024-11-26 08:03:48","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5525654/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5525654/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10965-025-04301-7","type":"published","date":"2025-02-26T15:57:16+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":71958324,"identity":"1865bb57-da2d-4230-ac64-5f1041c9ae27","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":95507,"visible":true,"origin":"","legend":"\u003cp\u003eThe synthesis route of PPCD with CO\u003csub\u003e2\u003c/sub\u003e and PO\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/1919590c883e1859239bd5ce.jpeg"},{"id":71958329,"identity":"4b7cd13d-b13b-4453-b428-a588e1ded280","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":186184,"visible":true,"origin":"","legend":"\u003cp\u003eThe solvent-free synthetic route of PPCD/PBA/PPG-WPU\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/5661a0df9ecf6a7447d3e2e6.png"},{"id":71959413,"identity":"dc675017-7ee0-4bb1-b574-e832f31a190d","added_by":"auto","created_at":"2024-12-20 06:25:20","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":271539,"visible":true,"origin":"","legend":"\u003cp\u003eFig.2-5 FTIR spectra of various PPCD and WPU. (a) FTIR spectra of various PPCD; (b) FTIR spectra of PPCD-WPU, PBA-WPU and PPG-WPU\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/d719176d7e55f42c5231214a.jpeg"},{"id":71958325,"identity":"29109731-4bef-4741-a015-dda84d021265","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":236433,"visible":true,"origin":"","legend":"\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eH NMR spectrum of PPCD-WPU\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/a05eb89fc8bf8dcee99a4d64.jpeg"},{"id":71958328,"identity":"2fa81fde-af8d-4085-80b3-08a6e7d74415","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":280519,"visible":true,"origin":"","legend":"\u003cp\u003eThe UV-vis transmittance of PPCD with different CO\u003csub\u003e2\u003c/sub\u003e content\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/e6df44cac164302684fb1d83.png"},{"id":71958330,"identity":"20329877-562b-46fd-b270-9c846d520cc3","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":516475,"visible":true,"origin":"","legend":"\u003cp\u003eTGA curves of PPCD\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/558d7e9a42bfd4a606f91375.jpeg"},{"id":71958334,"identity":"4695154d-fc3b-4a4c-a63b-a5455da5b264","added_by":"auto","created_at":"2024-12-20 06:17:20","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":68208,"visible":true,"origin":"","legend":"\u003cp\u003eDSC curve of PPCD with different CO\u003csub\u003e2\u003c/sub\u003e content\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/c92a8ad91f08eeb43b3a4d25.png"},{"id":71958340,"identity":"fe430ca7-8bdf-41f8-8a42-aa28b3452668","added_by":"auto","created_at":"2024-12-20 06:17:21","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":73323,"visible":true,"origin":"","legend":"\u003cp\u003eStress-strain curves of PPCD-WPU\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/fd67814a265cb948a1c0145c.png"},{"id":71959748,"identity":"79695eda-a1cb-495b-972b-21b04c7d96f3","added_by":"auto","created_at":"2024-12-20 06:33:20","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":58232,"visible":true,"origin":"","legend":"\u003cp\u003eStress-strain curves of WPU with different soft segments\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/6b966ba2ef7d472d0d5abfca.png"},{"id":77622440,"identity":"02502083-3e66-494f-b738-4f213c77cd26","added_by":"auto","created_at":"2025-03-03 16:06:50","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2573798,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5525654/v1/acf1fa69-3dc2-478a-98b7-ce7e8c593ebf.pdf"}],"financialInterests":"","formattedTitle":"Preparation of novel CO 2 copolymer diol and its application on waterborne polyurethane","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCarbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e), as a widely existing gas in nature, is also the exhaust gas emitted by human industrial production. The massive emission of carbon dioxide has broken the balance of the carbon cycle in nature, and has not been effectively recycled for a long time, which is the main reason for climate warming \u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e. At the same time, CO\u003csub\u003e2\u003c/sub\u003e, as a rich source of carbon resources, is a potential raw material for chemical synthesis\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. The resource utilization of carbon dioxide\u003csup\u003e[\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e can not only accelerate the realization of the goal of \u0026ldquo;carbon peaking and carbon neutrality\u0026rdquo;, but also synthesize polymer materials. The development of artificial carbon cycle can reduce the use of traditional petroleum-based materials and reduce dependence on non-renewable petroleum resources, which has a wide range of social, economic and environmental values \u003csup\u003e[\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eTherefore, the study of carbon dioxide polymerization and the preparation of materials with practical application value are more and more concerned by researchers. In recent years, great progress has been made in the preparation of polymer materials with CO\u003csub\u003e2\u003c/sub\u003e, PO, EO and other compounds and this method of synthesizing organic polymers makes great use of CO\u003csub\u003e2\u003c/sub\u003e gas. Among them, CO\u003csub\u003e2\u003c/sub\u003e copolymer diol (PPCD) is prepared by ring-opening polymerization with CO\u003csub\u003e2\u003c/sub\u003e and PO as the main raw materials, which can be used as a new raw material for the synthesis of polyurethane, and then realize the resource use of carbon dioxide materials.\u003c/p\u003e \u003cp\u003eAs an inert gas, carbon dioxide is extremely stable in thermodynamics. It is not reactive under general reaction conditions, so it is difficult to react with other reactants. In general, specific catalysts need to be added to break the carbon and oxygen bond for reaction under certain conditions of temperature and pressure. Therefore, it is extremely important to study the catalyst system and select the transformation path\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. At present, the research on the polymerization of carbon dioxide and epoxide mainly focuses on the development of efficient catalyst system. In 1969, Professor Shohei Inoue developed the diethyl zinc-water catalytic system (ZnEt\u003csub\u003e2\u003c/sub\u003e-H\u003csub\u003e2\u003c/sub\u003eO) to prepare carbon dioxide-based polymer by ring-opening copolymerization of CO\u003csub\u003e2\u003c/sub\u003e and PO. The preparation of high molecular weight resins by the polymerization of carbon dioxide has attracted more and more attention of researchers worldwide\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThen, a large number of basic researches have been carried out worldwide, and various catalyst systems for the preparation of carbon dioxid-based polymers have been developed, including organic zinc, salen, rare earth and bimetallic catalysts\u003csup\u003e[\u003cspan additionalcitationids=\"CR17 CR18 CR19\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. The catalytic efficiency of various systems is different with their own characteristics, among which the organic zinc catalyst has been studied most deeply, while the bimetallic catalyst (DMC) has been successfully applied in the industrial production of CO\u003csub\u003e2\u003c/sub\u003e copolymer diol. CO\u003csub\u003e2\u003c/sub\u003e copolymer diol, with reactable hydroxyl terminal structure at both ends of the molecular chain, can be used as raw materials to prepare polyurethane resin\u003csup\u003e[\u003cspan additionalcitationids=\"CR22 CR23\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e, replacing the traditional petroleum based polyols, which just satisfied the needs of the polyurethane field. It has become a new research field, and will continue to develop and explore its practical value in the future.\u003c/p\u003e \u003cp\u003eIn this paper, CO\u003csub\u003e2\u003c/sub\u003e and PO are used as raw materials to prepare colorless and water permeable PPCD with different CO\u003csub\u003e2\u003c/sub\u003e content through the improvement of the synthesis process, which solves the problem that there are too many residual metal catalysts of CO\u003csub\u003e2\u003c/sub\u003e copolymers and their colors are too dark and opaque, which limits their application in many fields. Then, We tried to use PPCD with high transparency to prepare waterborne polyurethane materials, and explore the influence of carbon dioxide content on the properties of waterborne polyurethane in detail. The combination of CO\u003csub\u003e2\u003c/sub\u003e polymer and waterborne polyurethane not only satisfies the real resource utilization of carbon dioxide materials, but also provides a new direction for the development of waterborne polyurethane industry. Therefore, the study has great practical significance.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eMain materials\u003c/h2\u003e \u003cp\u003eThe bimetallic catalyst (DMC,industrial grade) was supplied by Guangdong Dazhi Environmental Protection Technology Co., Ltd. (China). Carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026gt;\u0026thinsp;99.99%) was purchased from Guangzhou Shiyuan Gas Co., Ltd.(China). Epoxy propane (PO, industrial grade) was provided by Tianjin Dagu Chemical Plant, and it was soaked with 4A molecular sieve before use. Isophorone diisocyanate (IPDI, industrial grade) was purchased from Wanhua Chemical Group Co., Ltd. (China). 2,2-Dimethylol propionic acid (DMPA, AR), and stannous octoate (T9, AR) were purchased from Tianjin Damao Chemical Reagent Factory. Triethylamine (TEA, AR), acetone (AC, AR), ethylenediamine (EDA, AR), were obtained from from Aladdin Company.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePreparation of CO copolymer diols and CO based waterborne polyurethane\u003c/h3\u003e\n\u003cp\u003eFirst, carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) and Epoxy propane (PO) were charged in a dry high pressure flask with a mechanical stirrer and catalyzed by bimetallic catalyst (DMC). The mixture was reacted at 60\u0026deg;C under a certain pressure until the solid content of the solid content of the polymer reaches more than 97%, and then the heating is stopped. When the prepolymer is cooled to 40\u0026deg;C, stop stirring to obtain the intermediate product. After the process of removing by-products (PC) and catalyst, the CO\u003csub\u003e2\u003c/sub\u003e copolymer diols is obtained. The reaction scheme for the synthesis of CO\u003csub\u003e2\u003c/sub\u003e copolymer diol is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003ePreparation of waterborne polyurethane emulsion\u003c/h3\u003e\n\u003cp\u003eThe waterborne polyurethane was synthesized by traditional prepolymer method. First, PPCD, IPDI, DMPA were charged into a 1000 mL three-necked flask equipped with an electric stirrer under nitrogen atmosphere. T-9 (0.2 wt.% of PPCD) was added into the mixture, and the reaction mixture was heated up to 100\u0026deg;C to react for about 4 h until the theoretical -NCO content of the prepolymer was reached. Then, the mixture was cooled to about 40\u0026deg;C and add appropriate acetone to reduce the viscosity. The neutralizing agent (TEA) was added into the mixture for about 5 min. After the neutralization, the prepolymer was poured into cold deionized water (approximately 15\u0026deg;C) and stirred vigorously at approximately 3000 r/min until the prepolymer is completely dispersed. After that, EDA(dilute with ice water to 30 wt.%)was added to extend the final backbones and the emulsion was slowly heated up to 75\u0026deg;C for 2 h until the theoretical -NCO content of the system was complete reaction. Finally, PPCD-WPU emulsion was obtained after removing the solvent by vacuum decompression. The reactant proportion is listed in Table\u0026nbsp;1. The reaction scheme for the synthesis of WPUs is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eTable.1 Formulations of waterborne polyurethane\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample designation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePPCD/PBA/PPG(g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIPDI/DMPA/TEA/EDA/H\u003csub\u003e2\u003c/sub\u003eO(g)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-601-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e80/6/4.5/2.4/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-611-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e45/5/3.7/1.3/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-621-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35/5.7/4.3/1.3/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-632-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35/5.8/4.3/1.6/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePBA-2000-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35/5.7/4.3/1.3/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPG-2000-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35/5.7/4.3/1.3/260\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eCharacterizations\u003c/h3\u003e\n\u003cp\u003eThe viscosity and hydroxyl value of the polymer was tested in accordance with the enterprise standard Q/DZHB 10-2019 of Guangdong Dazhi Technology Co., LTD. The infrared absorption structure of the polymer was analyzed by Fourier Transform Infrared (FT-IR), with an appropriate amount of polymer resin uniformly tested on KBr salt sheets, and it was ftir analyzed in the range from 500 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to 4000 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The chemical structure of polymer was tested by \u003csup\u003e1\u003c/sup\u003eH NMR instrument at room temperature with 16 scanning times. Take appropriate amount of sample resin dissolved reagent grade deuterium chloroform, the concentration is about 3% ~ 5%, the sample is placed in a nuclear magnetic tube with a height of about 4 cm\u0026thinsp;~\u0026thinsp;5 cm, the CO\u003csub\u003e2\u003c/sub\u003e content of polymer is calculated according to the hydrogen displacement in the nuclear magnetic spectra.\u003c/p\u003e \u003cp\u003eThe transparency of appearance was tested by UV-vis spectrophotometer in accordance with ASTM D 1003-13. Take appropriate amount of sample resin into the colorimetric sample dish, after blank contrast, test the transmittance of resin. Thermogravimetric analyzer (TGA) was used to test the thermal decomposition performance. In nitrogen atmosphere, the flow rate was 20 mL/min, and the speed was set at 10 ℃/min. Polymer samples were tested from 25 ℃ to 500 ℃. Differential scanning calorimeter (DSC) was used to test \u003cem\u003eT\u003c/em\u003eg of PPCD resin, and nitrogen was used to cool the test with a flow rate of 50 mL/min. The sample test range was from \u0026minus;\u0026thinsp;50 ℃ to room temperature, and the sample test speed was set to 10 ℃/min.\u003c/p\u003e \u003cp\u003eThe tensile properties of WPU films was tested by electronic testing machine. The film prepared in advance was tested according to GB/T1040-92 standard. The spline was dumbbell type sample, the test rate was 200 mm/min, and the original distance was 25 mm.\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eInfrared spectrum of prepared PPCD and PPCD/PBA/PPG-WPU\u003c/h2\u003e \u003cp\u003eThe infrared absorption spectra of the main structures of CO\u003csub\u003e2\u003c/sub\u003e copolymer diol are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e (a). The most left wavelength is about 3500 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and there is an obvious wide absorption peak, which is the peak of hydroxyl terminal (-OH) in the structure of PPCD. The peaks in the range of 1780 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 785 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are due to the absorption of propylene carbonate (PC) carbonyl (C\u0026thinsp;=\u0026thinsp;O), a by-product generated in the synthesis of PPCD. The peaks at 1740 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1262 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are formed by the (-C\u0026thinsp;=\u0026thinsp;O) bond and (-C-O-) bond in carbonate bond. The peaks at 1378 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1067 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are attributed to the -C-O-C- structure of the polyether segment in the PPCD molecular chain. The infrared spectrum comprehensively reflects the characteristic absorption peaks of the main structures of PPCD.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe infrared spectra of PPCD-WPU film were analyzed in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e (b). The positions of absorption peaks of main structures were given, and compared with traditional waterborne polyurethane. In the PPCD-WPU infrared absorption spectrum, the peaks at 1740 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1262 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are attributed to the characteristic absorption peaks of (-C\u0026thinsp;=\u0026thinsp;O) and (-C-O-) bonds in the carbonate bond in the PPCD molecular chain. The PPCD molecular chain has both carbonate bond and polyether structure, and the characteristic peak is in the range of 1067 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Similarly, in the PBA-WPU absorption spectrum, the peak at 1728 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e is caused by the (-O-C\u0026thinsp;=\u0026thinsp;O-) group in the polyester structure. In the infrared absorption spectrum of PPG-WPU, the peak at 1100 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e was caused by ether bond (-COC-). There are absorption peaks at 1560 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, which are vibration absorption peaks of carboxylic acid in DMPA on the main chain structure. The results showed that the hydrophilic monomers reacted on the molecular backbone of waterborne polyurethane with different soft segment structures.\u003c/p\u003e \u003cp\u003e \u003csup\u003e \u003cb\u003e1\u003c/b\u003e \u003c/sup\u003e \u003cb\u003eH NMR spectra of prepared PPCD\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e (a, b), the characteristic molecular structure of PPCD with different CO\u003csub\u003e2\u003c/sub\u003e content can be characterized by \u003csup\u003e1\u003c/sup\u003eH NMR hydrogen spectrum. The carbon dioxide content in molecular chain segment can be calculated according to the peak area. As can be seen from \u003csup\u003e1\u003c/sup\u003eH NMR (400 MHz, CDCl\u003csub\u003e3\u003c/sub\u003e), CDCl\u003csub\u003e3\u003c/sub\u003e: δ (ppm)\u0026thinsp;=\u0026thinsp;7.28 (H, =CH\u003csub\u003e2\u003c/sub\u003e), 4.95 (1, H, -CH=), 4.85 (2, 1H, -CH=), 4.6 (3, 5, 2H, -CH\u003csub\u003e2\u003c/sub\u003e-), 3.9\u0026thinsp;~\u0026thinsp;4.3 (4, 2H, -CH\u003csub\u003e2\u003c/sub\u003e-), 3.3\u0026thinsp;~\u0026thinsp;3.8 (6, 2H, -CH\u003csub\u003e2\u003c/sub\u003e-, 7, H, -CH=), 1.55 (8, 3H, -CH\u003csub\u003e3\u003c/sub\u003e), 1.2\u0026thinsp;~\u0026thinsp;1.4 (9, 3H, - CH\u003csub\u003e3\u003c/sub\u003e), 1.0\u0026thinsp;~\u0026thinsp;1.21 (10, 11, 3H, -CH\u003csub\u003e3\u003c/sub\u003e).\u003c/p\u003e \u003cp\u003eTable 2 shows the basic physical and chemical properties of PPCD with different carbon dioxide contents. The carbon dioxide content, viscosity, hydroxyl value and other basic properties of PPCD were investigated. The content of carbon dioxide basically remained between 23% and 32%, which was greatly related to the actual polymerization conditions. The viscosity of PPCD-632 is the highest, which is mainly related to the content of carbon dioxide in the molecular chain, namely the carbonate group. High carbon dioxide content means the increase of the carbonate group in the molecular chain, the increase of intermolecular interaction force, easier to form hydrogen bonds and greater molecular cohesion. \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e Basic physical and chemica parameters of PPCD\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e content (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHydroxyl value(mgKOH/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eViscosity(mPa\u0026sdot;s)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003efunctionality\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-601\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e31.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e224\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e5000\u0026thinsp;\u0026plusmn;\u0026thinsp;500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-611\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e30.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e112\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e5000\u0026thinsp;\u0026plusmn;\u0026thinsp;500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-621\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e26.4\u0026thinsp;\u0026plusmn;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e56\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e6000\u0026thinsp;\u0026plusmn;\u0026thinsp;1000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-631\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e23.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e37\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e4000\u0026thinsp;\u0026plusmn;\u0026thinsp;500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-632\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e29.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e37\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e10000\u0026thinsp;\u0026plusmn;\u0026thinsp;1000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: Hydroxyl value was titrated by enterprise standard Q/DZHB 10-2019, CO\u003csub\u003e2\u003c/sub\u003e content was calculated by \u003csup\u003e1\u003c/sup\u003eH NMR, and viscosity was measured at 40 ℃.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eAppearance of PPCD\u003c/h3\u003e\n\u003cp\u003eTransparency is an important indicator of the appearance of the polymer, for applications in optical components, transparent medical material and UV curing coating and decoration of cosmetic requirements such as high field has an important influence, transparent resin has application prospect in many industries. The transparency of PPCD material was analyzed by UV-vis, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. The results indicated that the overall transmittance of PPCD reached more than 50% in the visible wavelength (380 nm\u0026thinsp;~\u0026thinsp;780 nm), and the transparency of PPCD-621, 631 and 632 resins is even higher than 90%, which means that PPCD can be used to prepare high transparency materials, and may be applied in the fields of light curing, 3D printing materials, optical lenses and display screens. However, with the increase of carbon dioxide content and the increase of carbonate structure, the UV-vis transmittance of resin decreased, indicating that carbon dioxide content in molecular structure may affect the transparency of resin. The ether bond and carbonate structure exist simultaneously in the molecular chain segment. The refractive index of the two structures is different to light, and the higher carbon dioxide content will cause the UV- vis transmittance of the resin to decrease.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eThermal properties of PPCD with different CO content\u003c/h3\u003e\n\u003cp\u003ePPCD mainly have carbonate bond, ether bond and side methyl structure, according to the different synthesis process and formula, the content of various groups in the molecular structure will be different, so when investigating the heat resistance of polyols, there are differences in thermal decomposition temperature. Thermogrgravity analysis (TGA) of PPCD-601, PPCD-611, PPCD-621, PPCD-631 and PPCD-632 was compared to explore the thermal degradation process. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e and Table\u0026nbsp;3. On the whole, only a small amount of mass loss before 200 ℃, resin can remain stable, trace mass loss is likely to be unvolatile water or by-products. With the increase of temperature, the mass loss of resin began to increase. The mass loss temperatures of 5\u003csub\u003ewt\u003c/sub\u003e.%, 10 \u003csub\u003ewt\u003c/sub\u003e.% and 50 \u003csub\u003ewt\u003c/sub\u003e.% of the resin were compared, respectively. As shown in Table\u0026nbsp;3, the 5 \u003csub\u003ewt\u003c/sub\u003e.% mass loss temperature of PPCD-632 was 240.1 ℃, while the 5 \u003csub\u003ewt\u003c/sub\u003e.% mass loss temperature of PPCD-601 was 205.8 ℃. In the process of 5% ~ 10% mass loss, the curve decreases obviously. The mass loss at this stage is mainly caused by the volatilization of by-products in the polymer. A small amount of propylene carbonate (PC) monomer is generated during the synthesis of PPCD. Therefore, the initial mass loss of thermal analysis is mainly caused by the volatilization of by-products. At 50 \u003csub\u003ewt\u003c/sub\u003e.% mass loss of the polymer, the temperature range of the five samples was 314.5 ℃ to 321.1 ℃, with little difference in temperature range. It shows that the material has good heat resistance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTable.3 Thermogravimetric temperature of PPCD\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabb\" border=\"1\"\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eT\u003csub\u003e5 wt.%\u003c/sub\u003e\u0026nbsp;(\u0026deg;C)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT\u003csub\u003e10 wt.%\u003c/sub\u003e\u0026nbsp;(\u0026deg;C)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT\u003csub\u003e50 wt.%\u003c/sub\u003e\u0026nbsp;(\u0026deg;C) )\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-601\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e205.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e246.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e314.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-611\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e215.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e252.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e315.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-621\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e221.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e264.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e320.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-631\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e232.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e268.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e321.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-632\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e240.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e270.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e319.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eGlass transition temperature of PPCD with different CO\u003csub\u003e2\u003c/sub\u003e content\u003c/h2\u003e \u003cp\u003eGlass transition temperature (\u003cem\u003eT\u003c/em\u003eg) of polymers is an inherent property of materials, closely related to molecular movement and structure, and the level of \u003cem\u003eT\u003c/em\u003eg has a great influence on the application of materials. Differential scanning calorimetry (DSC) was used to analyze the prepared PPCD to explore the influence of different carbon dioxide content on the glass transition temperature of the polymer. As can be seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e, different carbon dioxide content in the polymer has a great influence on the glass transition temperature of the prepared PPCD. Due to the high content of carbonate bond in the molecular structure of PPCD-601 and PPCD-611, the \u003cem\u003eT\u003c/em\u003eg of the polymer also increases, reaching the region of -34.5 ℃ and \u0026minus;\u0026thinsp;35.1 ℃. And as the carbon dioxide content in the polymer decreases, the \u003cem\u003eT\u003c/em\u003eg of the polymer moves to a lower temperature. The main reason affecting the glass ring transition temperature is that the introduction of synthetic carbonate groups in the polymer with increased carbon dioxide enhances the polarity of PPCD molecular chain segment, and the flexibility and movement of molecular chain segment are limited, thus increasing the glass transition temperature. The high glass transition temperature of PPCD-601 and PPCD-611 is due to the high carbon dioxide content of the synthetic polymer molecular chain up to 31.5%. The glass transition temperature of PPCD-631 is the lowest, reaching \u0026minus;\u0026thinsp;49.7 ℃ and the carbon dioxide content of the polymer is low, only about 23%, the number of polar groups on the molecular chain is relatively small, and the structural flexibility of the molecular chain is improved. The \u003cem\u003eT\u003c/em\u003eg of the polymer is obviously affected by the CO\u003csub\u003e2\u003c/sub\u003e content in the structure, so the performance of the polymer can be controlled according to the actual situation.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eMechanical properties of PPCD-WPU\u003c/h2\u003e \u003cp\u003ePPCD was used as a raw material to prepare waterborne polyurethane resin. It is an effective way to judge the mechanical properties of the noval waterborne polyurethane resin by investigating its basic tensile properties, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e. Table\u0026nbsp;4 shows the relationship between stress and strain of PPCD-WPU film. It can be found that the mechanical properties of PPCD-WPU are affected by the CO\u003csub\u003e2\u003c/sub\u003e content in the soft section. When the CO\u003csub\u003e2\u003c/sub\u003e content of PPCD molecular chain reaches about 31.5%, the tensile strength of the prepared PPCD 601-WPU film reaches the highest, while the elongation at break is the lowest. When the CO\u003csub\u003e2\u003c/sub\u003e content in PPCD molecular chain is 26.4%, the tensile strength of the prepared PPCD 631-WPU film is 23.27 MPa, which is the lowest value among the five samples. At this time, the elongation at break is 750.85%, which is in a high range. The results showed that with the increase of CO\u003csub\u003e2\u003c/sub\u003e content in the molecular structure of PPCD, the mechanical strength of PPCD-WPU was enhanced, but the elongation of PPCD-WPU was affected to some extent. PPCD molecular structure contains strong polar carbonate groups and ether bond structure with good flexibility. By regulating their relative contents in molecular structure, PPCD-WPU can be prepared to satisfy the needs of practical applications.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTable.4 Tensile strength and elongation at break of PPCD-WPU\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabc\" border=\"1\"\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e content of soft segment(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eσ(MPa)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eε\u003c/em\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-601-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e31.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e34.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e520.37\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-611-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e30.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e32.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e565.28\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-632-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e29.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e31.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e723.52\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-621-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e26.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e819.45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-631-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e23.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e750.85\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTable.5 Tensile strength and elongation at break of PPCD-WPU\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabd\" border=\"1\"\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eM\u003c/em\u003en(g/mol)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eσ(MPa)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eε\u003c/em\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPCD-621-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e819.45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePBA-2000-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e805.81\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPG-2000-WPU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e11.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1232.48\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn order to compare the performance of PPCD-WPU, polyester waterborne polyurethane (PBA-WPU) and polyether waterborne polyurethane (PPG-WPU) were selected for comparison with the mechanical properties of PPCD-621-WPU. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e and Table\u0026nbsp;5, it can be found that the tensile platform of PCD-621-WPU film is significantly higher than that of the other two traditional waterborne polyurethanes, proving that PPCD-621-WPU has strong partial plasticity. The stress and tension of PBA-WPU reaches 30.35 MPa, while that of PPG-WPU film is 11.24 MPa. The elongation is the longest, reaching 1232.48%. The tensile strength of PPCD-621-WPU film has reached the performance of polyester, and the elongation can also be maintained well. This has a great relationship with the molecular structure of PPCD. There are a large number of polar groups of carbonate in the molecular structure and ether bonds in the structure, which has both strength and flexibility. The waterborne polyurethane prepared from PPCD is a new material with excellent performance.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eA series of CO\u003csub\u003e2\u003c/sub\u003e copolymer diol (PPCD) were prepared with carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) and epoxide (PO). The basic structure and physical and chemical properties of PPCD were characterized by modern testing methods. Firstly, the molecular structure of PPCD was analyzed by FT-IR. The characteristic absorption peaks of carbonate bond and ether bond in polymer structure were obtained.The chemical shift of hydrogen on the polymer structure was analyzed by \u003csup\u003e1\u003c/sup\u003eH NMR, and the CO\u003csub\u003e2\u003c/sub\u003e content of PPCD was calculated to be between 23.5% and 31.5% by absorption peak area. The appearance of PPCD was characterized by ultraviolet visible spectroscopy (UV-vis). The overall visible light transmittance of PPCD was more than 90% in the range of UV-visible light (80 nm\u0026thinsp;~\u0026thinsp;3 nm), which can be used to prepare high transparency materials. Thermogravimetric analysis (TGA) was used to investigate the thermal stability of PPCD. The significant mass loss occurred only when the temperature was above 200 ℃. When the mass loss reaches 50%, the decomposition temperature is between 314.5 ℃ and 321.1 ℃, indicating that PPCD polymer has good thermal stability. Differential scanning calorimetric analysis (DSC) was used to analyze the PPCD. It was found that the glass transition temperature of the polymer was closely related to the carbon dioxide content in the polymer. PPCD-601 with CO\u003csub\u003e2\u003c/sub\u003e content of 31.5% has a \u003cem\u003eT\u003c/em\u003eg of -34.5\u0026deg;C, while PPCD-631 with carbon CO\u003csub\u003e2\u003c/sub\u003e content of 23.5% has a \u003cem\u003eT\u003c/em\u003eg of -49.7 ℃, which is obviously higher. Then, PPCD was used as raw material to prepare waterborne polyurethane (PPCD-WPU). The mechanical properties of PPCD-WPU with different CO\u003csub\u003e2\u003c/sub\u003e content were compared by mechanical property test. It was found that WPU with high CO\u003csub\u003e2\u003c/sub\u003e content in soft segment had great influence on tensile strength, which was mainly caused by the joint action of carbonate bond and ether bond in the molecular structure of soft segment. At the same time, compared with polyester and polyether waterborne polyurethane, PPCD-WPU has high strength and flexibility, and the molecular structure of PPCD is adjustable. It is expected to provide a new raw material with economic and social value for the polyurethane industry in the future.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eConflict of interest\u003c/h2\u003e \u003cp\u003eWe declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAcknowledgment\u003c/h2\u003e \u003cp\u003eThis work was supported by the Doctoral Research Initiation Project of Huizhou University (Grant No. 15602230032 and 15602245011) and the Undergraduate Innovation and Entrepreneurship Training Program (Grant No.240170004010).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDuan Wenjuan. International Energy Agency released a report: global carbon emissions hit a record high last year [J]. 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Journal of Polymer Research, 2021, 28(7):254\u0026ndash;264.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-polymer-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jpol","sideBox":"Learn more about [Journal of Polymer Research](https://www.springer.com/journal/10965)","snPcode":"10965","submissionUrl":"https://www.editorialmanager.com/jpol/","title":"Journal of Polymer Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"CO2 polymerization, CO2 copolymer diol, Waterborne polyurethane","lastPublishedDoi":"10.21203/rs.3.rs-5525654/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5525654/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e copolymer diol (PPCD) with superior transparency is an indispensable raw material for the polyurethane polymers, especially for water-based polyurethane coatings. However, commercial PPCD is generally opaque. In this work, A novel sustainable, colorless and transparent PPCD was prepared by using carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) and propylene oxide (PO) as raw materials. Its basic structure was tested and verified by Fourier transform-infrared (FT-IR) and proton nuclear magnetic resonance (\u003csup\u003e1\u003c/sup\u003eH NMR) spectroscopy. Appropriate increase CO\u003csub\u003e2\u003c/sub\u003e content did not obviously reduce the transparency and thermal stability of PPCD and the optimum value was 29.1 wt.%. Furthermore, the waterborne polyurethane (WPU) was successfully synthesized by prepolymer method with poly(1,4-butylene adipate) (PBA), polypropylene glycol (PPG) or prepared PPCD as the soft segment, respectively. With the increase of CO\u003csub\u003e2\u003c/sub\u003e content, the thermodynamic property of WPU was significantly improved. When CO\u003csub\u003e2\u003c/sub\u003e content increased from 23.50 wt.% to 31.50 wt.%, the tensile strength increased from 23.27 MPa to 64.63 MPa and the elongation at break decreased from 750.85\u0026ndash;520.37%, accompanied by the glass-transition temperature increased from \u0026minus;\u0026thinsp;49.7 ℃ to -34.5 ℃. In addition, the WPU prepared by PPCD was also found to have better tensile strength, transparency and storage stability than that prepared by PBA and PPG. A new inspiration was provided to develop high-transparent CO\u003csub\u003e2\u003c/sub\u003e based water-based polyurethane coatings.\u003c/p\u003e","manuscriptTitle":"Preparation of novel CO 2 copolymer diol and its application on waterborne polyurethane","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-20 06:17:15","doi":"10.21203/rs.3.rs-5525654/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2024-12-18T11:07:51+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-12-18T10:46:34+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Journal of Polymer Research","date":"2024-11-28T21:12:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-27T11:01:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Polymer Research","date":"2024-11-27T02:42:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-polymer-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jpol","sideBox":"Learn more about [Journal of Polymer Research](https://www.springer.com/journal/10965)","snPcode":"10965","submissionUrl":"https://www.editorialmanager.com/jpol/","title":"Journal of Polymer Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"8fd8f6e3-34cc-4988-9371-20604e54d7a1","owner":[],"postedDate":"December 20th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-03-03T16:00:36+00:00","versionOfRecord":{"articleIdentity":"rs-5525654","link":"https://doi.org/10.1007/s10965-025-04301-7","journal":{"identity":"journal-of-polymer-research","isVorOnly":false,"title":"Journal of Polymer Research"},"publishedOn":"2025-02-26 15:57:16","publishedOnDateReadable":"February 26th, 2025"},"versionCreatedAt":"2024-12-20 06:17:15","video":"","vorDoi":"10.1007/s10965-025-04301-7","vorDoiUrl":"https://doi.org/10.1007/s10965-025-04301-7","workflowStages":[]},"version":"v1","identity":"rs-5525654","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5525654","identity":"rs-5525654","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}