Characterization and experimental study on novel nano-enhanced binary phase change material for cold chain logistics

Characterization and experimental study on novel nano-enhanced binary phase change material for cold chain logistics | 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 Characterization and experimental study on novel nano-enhanced binary phase change material for cold chain logistics Joel Silas S, Mariappan V, Arun M, Karthikeyan K This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7201833/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 27 Oct, 2025 Read the published version in International Journal of Thermophysics → Version 1 posted 10 You are reading this latest preprint version Abstract Novel nano-enhanced phase change materials (NEPCMs) for vaccine storage applications have been developed for vaccine transportation. Phase change materials(PCMs) are highly regarded due to their excellent heat storage capacities and their ability to operate within a limited temperature range. Nonetheless, their low thermal conductivity restricts their applicability. A binary mixture of caprylic acid (CL) and capric acid (CA) with a weight fraction of 58:42 was developed for the passive cooling application. The CL-CA binary mixture exhibits a melting enthalpy (H m ) of 119.07 Jg − 1 and a melting temperature (T m ) of 7.66°C. Boron nitride (BN) was used as a thermal conductivity enhancer for the above binary mixture. BN was added in various weight percentages of 0.5%, 1%, 1.5%, and 2% in the binary mixture to develop NEPCMs. There was an improvement of 12.1% in thermal conductivity for 2% BN from the base binary mixture. Furthermore, thermal cycling has been done and the samples have maintained stability and phase change characteristics as confirmed using FTIR (Fourier transform infrared spectroscopy), thermal conductivity, and DSC (Differential scanning calorimetry). Thermal conductivity Boron nitride Phase change material Latent heat Nano enhanced Phase change materials Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 1. Introduction The immune system is being improved by vaccines, which help us to fight against bacteria and viruses. The vaccine box usually maintains a specified temperature range inside it to store, transport, and preserve the vaccine. Otherwise, the vaccine loses its potency, fails to protect against disease, and results in an inadequate immune response[ 1 ]. To control the temperature of the vaccine storage cabin, passive cooling is employed as active cooling consumes more energy. Passive cooling achieves temperature regulation through PCMs and appropriate insulation material. PCMs are substances used for storing energy by absorbing and releasing heat[ 2 , 3 ]. When a substance transitions from solid to liquid, or liquid to solid thermal energy is transferred [ 4 , 5 ]. The current study focuses on fatty acid-based binary PCMs as it offers advantages like congruent melting, chemical stability, non-toxicity, cost-efficiency, and phase transition in the required temperature range but less thermal conductivity[ 6 ]. To avoid the low thermal conductivity of PCM foreign particles like nanoparticles, nanotubes, nanofibers, and nanosheets have been added to the PCM to improve its thermal conductivity. The added nanoparticles act as a nucleating agent and enable a congruent phase change process in CPCMs (Composite phase change material). Numerous methods have been employed by prior researchers to add the nanoparticles to PCM like vacuum impregnation, varnish layer, autoclave, stirring, ultrasonication, and kneader mixing technique. Then the PCMs thermal conductivity is assessed using the laser flash method, transient plane source method, transient state method and transient hot wire method[ 7 ]. 1-Dodecanol and caprylic acid eutectic mixture had a H m of 171.06 Jg − 1 and a T m of 6.52°C was found to retain its enthalpy even after 60 and 120 thermal cycles[ 8 ]. A Binary mixture of n-octanoic acid and myristic acid was prepared with a weight ratio of 87:13 and 7 weight % EG was added to improve the thermal conductivity of the mixture and was reported as 0.9975 W.m − 1 . K − 1 which was 235.75 % more than that of te base sample, its melting point and H m was 6.8°C and 136.3 Jg − 1 [ 9 ]. The thermal conductivity of Caprylic acid was improved when adding 0.5 weight % of synthesized nanoparticles like CuO, Ag, ZnO, and GO by 36%, 52%, 43%, and 87% respectively[ 10 ]. Two commercial PCMs, namely C-18 and E-21, used in a refrigerator evaporator to minimize the temperature rise in the cabinet, have been encapsulated in a stainless-steel container. Compared to C-18(-12/-7°C), the air temperature was maintained at a lower temperature(-16/-12°C) when E-21 was used as PCM [ 11 ]. Three nanoparticles namely nano copper, nano silver, and graphene, were added to magnesium nitrate hexahydrate with a thickening agent carboxy methyl cellulose. By adding nanoparticle with 0.5, 1 and 1.5 weight percentages, there was an improvement in thermal conductivity of the base PCM. Upon adding graphene in 0.5, 1, and 1.5 weight percentages, there was an increase in thermal conductivity of 92.43%, 107.5%, and 138.4% with respect to the base PCM[ 12 ]. A composite PCM was prepared by using a eutectic salt solution and modified expanded graphite. The modified expanded graphite was prepared by coating SiO 2 on the expanded graphite surface. The prepared form stable PCM has a T m of -5.6°C and an H m of 180.8 Jg − 1 . Thermal conductivities of the eutectic salt PCM and the modified PCM were 0.575 W m − 1 . K − 1 and 5.183 W.m − 1 . K − 1 , confirming eight times increase in thermal conductivity[ 13 ]. There are very few works on melting points ranging from 2–8°C for vaccine storage applications, which creates more interest in finding a PCM with a good latent heat with improved thermal conductivity. In this study, novel NEPCMs consisting of CL-CA binary mixture as PCM and incorporating BN nanoparticles of 0.5%,1%,1.5%, and 2% weight percentages to the CL-CA binary mixture have been prepared to cater the needs of the vaccine storage and transportation industry. To the best of the author’s knowledge, there are no prior studies reporting the incorporation of BN nanoparticles into CL-CA for the improvement of thermal conductivity. 2. Materials and Experimentation 2.1 Preparation of CL-CA binary mixture and NEPCMs CL, CA, and BN nanoparticles were procured from Sisco Research Laboratory Pvt. Ltd., India. All materials used in this study were used without further purification. The NEPCMs were prepared in two steps. First, mechanical stirring was done to guarantee proper mixing of PCM, followed by ultrasonication to promote homogenous dispersion. To achieve the application temperature of 2–8°C, a CL-CA binary mixture was prepared, consisting of two PCMs weighed separately in a ratio of 58:42. The CL-CA binary mixture was heated to 60°C and stirred at 600 rpm for 1 hour using a thermostatic magnetic stirrer and then exposed to ultrasonication at 60°C for 30 minutes. Four Different NEPCMs were prepared by adding nanoparticles in 0.5, 1, 1.5, and 2% weight percentages to the CL-CA binary mixture by stirring and ultrasonication procedure. After this procedure, the prepared samples were naturally cooled to obtain NEPCMs. Figure 1 . depicts the image of the prepared samples namely CL,CA,CLCA(58:42),0.5% BN,1% BN,1.5% BN and 2%BN. 2.2 Experimentation A transient experiment was conducted to evaluate the heat transfer performance of the prepared binary mixture and 2% BN. A 50 mL spherical flask was taken and filled up to 90% of its volume with two samples. The chiller was filled with a 60:40 water-ethylene glycol ratio and this was used as heat transfer fluid (HTF). The HTF level was made above the PCM level for better heat transfer. A small hole was drilled in the cork for inserting the K-type thermocouple. For the charging behavior of the samples, the chiller was set to a temperature of -8°C, and the samples were immersed in the chiller along with a calibrated K-type thermocouple which is shown in Fig. 2 . Based on the calibration, it can be inferred that the temperature is accurate within ± 0.34°C. The thermocouple is connected to a data acquisition system, DAQ 970A KEYSIGHT, with an accuracy of ± 0.9°C and the data was logged for every 5 seconds. The experiment was conducted twice to assess the reproducibility. For the Discharging process, first, the sample was frozen in a separate freezer and then immersed in the chiller with a set temperature of 25°C. 3. Results and discussion 3.1 Morphology of nanoparticle The SEM (Scanning electron microscope) image taken by Carel zeiss EVO 18 reveals the boron nitride nanoparticle to be of a crystalline hexagonal layered structure. Strong covalent connections bind the atoms of boron and nitrogen within each layer, while weak van der Waals forces bind the layers together. The SEM image shown in Fig. 3 with a diameter of 138.6 nm[ 14 ] and an average particle size of 70 nm as reported in [ 15 ] 3.2 Particle size distribution of nanoparticle The particle size analyzer is used to determine the size distribution of a suspension, a powder, and an emulsion based on light diffraction. The particle size distribution curve is in Fig. 4 . The obtained results were similar to [ 14 ]. The BN had an average particle size of 70nm, a specific surface area of 19.4 m 2 g − 1 , a density of 2.26 g cm − 3, and a diameter of 138.6 nm. The Particle size distribution of (D10%), (D50%), and D (90%) were 73.20 nm,141.10 nm, and 283 nm, respectively. 3.3 X-ray Diffraction analysis of nanoparticle The crystalline structure of the nanoparticle is ascertained employing the X-ray diffraction (XRD) method. The XRD pattern was obtained using Ultima IV unit (Make: Rigaku) emitting Cu-Kα radiation with a wavelength (λ) of 1.5406 \(\:\AA\:\:\) operated at 30 mA of beam current and 40 kV of accelerating voltage. The diffraction pattern of BN is collected in the 2θ ranging from 10 ° to 90°, for a step size of 0.05° with a scanning rate of 1°min − 1 . This is shown in Fig. 5 . The crystal system of the BN nanoparticle was determined to be hexagonal in shape with lattice constants a = 2.51 \(\:\AA\:\) , b = 2.51 \(\:\AA\:,\) and c = 6.96 \(\:\AA\:\) . There is a strong peak at 2θ = 26.62° corresponding to the diffraction plane (002) and weak peaks at 40.41°, 43.75°, 54.84°, 77.29° and 81. 92° corresponding diffraction planes (003), (101), (004), (111), and (112) respectively, which is similar to [ 14 ].The XRD pattern of BN agreed with the Joint Committee on Powder Diffraction Standards (JCPDS) reference code 96-101-0331. 3.4 Spectroscopic analysis of the samples FT-IR analysis was done to find the chemical stability of the NEPCMs and to determine the PCMs functional group. An investigation using was conducted using a perkin elmer spectrum two, FT-IR spectrometer equipped with LiTaO3 detector, having a resolution of 2 cm − 1 and 8 scans. The resulting spectra are illustrated in Fig. 6 . This test was performed to evaluate the chemical stabilities of the CL-CA binary mixture containing boron nitride nanoparticles. The existence of the carboxyl group of CA is shown by the stretching vibration at 1706 cm − 1 which is attributed to the C = O group. The peaks present in the wavenumber 2857 cm − 1 and 2952 cm − 1 are due to the CH 2 and CH 3 alkane groups. This result was found to agree with [ 16 ]. The three peaks at 2956.25 cm − 1 , 2925cm − 1 , and 2857 cm − 1 confirm the CH 3 and CH 2 stretching of the alkane group in the CL and a knife-like peak at 1706.08 cm − 1 attributed to ‒C = O of the carboxylic acid group, the peaks were in line with[ 4 ]. NEPCMs did not exhibit any extra absorption peaks, indicating that surface tension and capillary action were the main factors influencing the CL-CA binary mixture and nanoparticles[ 16 ].The nano enhanced PCM was formed only by physical mixing without changing the structure of CL-CA binary mixture. It can be observed that all the major peaks present in the FTIR spectra of the thermally cycled PCM samples were identical to those in the spectra of the uncycled PCM sample. 3.5 Phase transition analysis of NEPCMs The enthalpy and melting point of the NEPCMs were determined by the DSC test. Setaram instrument, which has an accuracy of ± 0.8% and a precision of 2.5%, was used to take the enthalpy values of the samples. The samples were loaded in an alumina crucible and were subjected to a heating and cooling rate of 2°Cmin − 1 at a temperature range of -15°C to 40°C with inert nitrogen. The T m and T f (freezing temperature) of pure capric acid was found to be 30.914°C and 26. 94°C.The H m and H f (freezing enthalpy) of capric acid were found to be 135 Jg − 1 and 134.55 Jg − 1; furthermore, T m and T f of pure caprylic acid were 16.20°C and 12.11°C. The H m and H f were 141.46 Jg − 1 and 134.55 Jg − 1 . The DSC plot depicts the peak melting point of the CL-CA binary mixture as 7.66°C and its H m as 119.07 Jg − 1 . The melting and freezing DSC curves are in Fig. 7 and Fig. 8 . The DSC results of the prepared binary mixture revealed that the melting point was consistent with the previous study [ 17 ]. The H f for the binary mixture was found to be 119.44 Jg − 1 . The percentage decrease in H m of nano-enhanced PCM with respect to the binary mixture was found to be 4.5%, 5.6%, 10.7%, and 19.4% respectively. After 100 thermal cycles again DSC test was performed again for 2 samples, CL: CA binary mixture and 2% BN and there was a slight decrease in both H m and H f . The H m and H f for CL- CA binary mixture came out to be 103.19 Jg − 1 and 102.78 Jg − 1 . The H m and H f for 2% BN is 93.89 Jg − 1 and 91.23 Jg − 1 . After thermal cycling, the percentage decrease of Hm for CL: CA binary mixture is 13.33% and that of 2% BN is 2.16%. Three heating and cooling cycles were performed, and the average values are reported. 3.6 Thermal conductivity assessment of samples The prepared samples' thermal conductivities were measured using thermtest measurement platform, MP-2 portable meter using a transient hot wire L3 sensor which has a measuring range of 0.1-1 Wm − 1 K − 1 and an accuracy of 5%.The transient hot wire sensor is a wire that is suspended between two contact points and is inserted in the test cell which can hold 20 mL of the sample with a stabilization of 10s and a test time of 1s. The heat transfer efficiency and speed of heat transfer are determined by thermal conductivity. The thermal conductivities of the pure sample CL, CA and CL-CA binary mixture were 0.151W.m − 1 . K − 1 ,0.153 Wm − 1 . K − 1 and 0.148 Wm − 1 . K − 1 individually. This can be seen in Fig. 9 . The percentage increase for 0.5%, 1%, 1.5%, and 2% weight percentage BN in comparison to the binary mixture of CL-CA were 3.3%, 4.7%, 10.1%, and 12.1%. This is because nanoparticles are smaller in size and have high aspect ratio which causes intermolecular interaction and Brownian motion within the base PCM [ 7 ]. After thermal cycling the thermal conductivity test was done for 2 samples CL: CA(58:42) and 2% BN respectively. There is a 0.67 % nd 1.8% decrease for CL-CA binary mixture and 2% BN respectively.The reported thermal conductivity values are taken thrice and averaged value is reported. 3.7 Thermal cycling tests To evaluate the thermal reliability of the prepared Nano-Enhanced Phase Change Materials (NEPCMs), the samples were subjected to repeated thermal cycling using a programmable thermal cycling chamber (model DQ-TC-002, Make: Digiqual Systems) with a 30-liter capacity[ 18 ] which is depicted in Fig. 10 . The chamber is equipped with sample trays and a PID-controlled system for precise temperature regulation. The NEPCM samples, each weighing 30 grams and contained in 100 mL beakers, were exposed to a temperature range of − 15°C to 15°C for a total of 100 continuous thermal cyclesI.Initially, the chamber was cooled to -15°C to stabilize the sample at the starting temperature. Each thermal cycle involved heating the sample from − 15°C to 15°C holding at 15°C for 15 min, and subsequently cooling it back to -15°C. Following the cycling process, the samples were analyzed using Differential Scanning Calorimetry (DSC), thermal conductivity measurements, and Fourier Transform Infrared Spectroscopy (FTIR) to assess changes in thermal performance and structural stability. 3.8 Charging and discharging curve The graph is plotted between time and temperature. We can observe from the graph Fig. 11 a) that there is sensible cooling from 0 to 10 minute(min) and 0 to 15min for CL: CA (58:42) and 2% BN, respectively. In this phase, heat is extracted as the PCM cools. Then there is phase change happening where the heat is released as the PCM solidifies which is represented from the 10th min to 65 min for the binary mixture and 15 min to 52 min for 2% BN, then again sensible cooling phase which happens from 65th min to 140 min and 52 min to 138 min for CL-CA binary mixture and 2% BN respectively. The nanoparticle enhanced PCM reached low temperature more rapidly than the binary mixture. This behavior suggests that the presence of nanoparticle promotes faster nucleation and solidification. In the discharging phase for CL-CA binary mixture there is 0 to 7th min and phase change from 7 to 17th min and again sensible heating from 17th to 25th min. For 2% BN there is sensible heating from 0 to 5th min as the temperature rises rapidly because it absorbed heat more quickly. Then phase change from 5th to 11th min and again there is sensible heating from 11 to 24th min for 2% BN which is shown in Fig. 11 b). The smoother temperature rise of 2% BN during melting implies uniform heat absorption, potentially indicating enhanced thermal dissipation enabled by nanoparticles. The rate of charging and discharging, and the duration of phase change, are important to evaluate the feasibility of phase change materials. 4.Conclusion In conclusion, the prepared novel NEPCMs have excellent potential for vaccine storage and transportation applications as it has the T m in the range of 2–8°C.The following conclusions were drawn from the above characterization The binary PCM mixture has T m = 7.66°C, T f = -0.984°C, and phase change enthalpies H m =119.07 Jg − 1 and H f =119.44 Jg − 1 . For 2% of BN in the binary mixture, the phase change temperatures of T m =7.24°C and T f =1.033°C and phase change enthalpies were H m = 95.96 Jg − 1 , H f =94.91 Jg − 1 . The thermal conductivity of the binary mixture is 0.148 Wm − 1 . K − 1 and for 2% of BN, the thermal conductivity is 0.166 Wm − 1 K − 1 which confirms an increase in thermal conductivity of 12.1%. FT-IR results confirm that there is no new peak formed in the NEPCMs after adding BN, indicating only physical interaction and proving good chemical stability with the CL- CA binary mixture. Based on the thermal cycling results for 100 melting/freezing cycles confirmed that the CL-CA binary mixture and 2% BN is stable and can be used as a potential material for the cooling application. The results indicate that the prepared sample exhibits favorable properties during both melting and freezing, making it a promising candidate for efficient low-temperature thermal energy storage systems. Declarations Author Contribution Joel Silas S: Conceptualization, Methodology, and Writing. Mariappan V: Investigation and Supervision. Arun M: Methodology, Data Curation, and Review. Karthikeyan K: Software and writing. Acknowledgments No specific grant from a public, private, or nonprofit funding organization was obtained for this study. References A. K. Ray, S. Singh, D. Rakshit, and Udayraj, Thermal Science and Engineering Progress 27 , (2022). S. Mo, L. He, L. Jia, Y. Chen, and Z. Cheng, Int J Thermophys 41 , (2020). Z. Younsi, L. Zalewski, S. Lassue, D. R. Rousse, and A. Joulin, Int J Thermophys 32 , 674 (2011). J. R. Vennapusa, A. Konala, P. Dixit, and S. Chattopadhyay, Mater Chem Phys 253 , (2020). D. Kim, J. Jung, Y. Kim, M. Lee, J. Seo, and S. B. Khan, Int J Heat Mass Transf 95 , 735 (2016). K. Karthikeyan, V. Mariappan, P. Kalidoss, R. Anish, P. Sarafoji, J. Venkatanageswara Reddy, and T. Kumar Satpathy, Mater Lett 328 , (2022). B. Eanest Jebasingh and A. Valan Arasu, Energy Storage Mater 24 , 52 (2020). J. Zuo, W. Li, and L. Weng, Energy Build 43 , 207 (2011). Y. Wang, X. Zhang, J. Ji, Y. Li, J. M. Munyalo, B. Liu, X. Xu, and S. Liu, J Mol Liq 288 , (2019). P. Sivasamy, S. Harikrishnan, R. Jayavel, S. I. Hussain, S. Kalaiselvam, and L. Lu, Mater Res Express 6 , (2019). E. Oró, L. Miró, M. M. Farid, and L. F. Cabeza, in International Journal of Refrigeration (2012), pp. 1709–1714. H. Wang, L. Guo, K. Liu, Z. Song, L. Wu, M. Fang, and J. Li, Mater Res Express 6 , (2019). X. Chen, Y. Fang, Z. Zhang, X. Gao, and J. Niu, International Journal of Refrigeration 160 , 402 (2024). F. Kar, C. Hacıoğlu, Y. Göncü, İ. Söğüt, H. Şenturk, D. Burukoğlu Dönmez, G. Kanbak, and N. Ay, J Clust Sci 32 , 517 (2021). R. Naresh Muthu, S. Rajashabala, and R. Kannan, Renew Energy 85 , 387 (2016). K. Karthikeyan, V. Mariappan, P. Kalidoss, J. Mohana Jai Ganesh, P. V. R. Nanda Kishore, S. Prathiban, and R. Anish, J Energy Storage 74 , (2023). S. Zhang, X. Zhang, X. Xu, and Y. Zhao, (n.d.). V. Santhosh Reddy, S. Venkatachalapathy, and P. Kalidoss, Energy Sources, Part A: Recovery, Utilization and Environmental Effects 45 , 1424 (2023). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 27 Oct, 2025 Read the published version in International Journal of Thermophysics → Version 1 posted Editorial decision: Revision requested 19 Aug, 2025 Reviews received at journal 19 Aug, 2025 Reviewers agreed at journal 11 Aug, 2025 Reviews received at journal 28 Jul, 2025 Reviewers agreed at journal 27 Jul, 2025 Reviewers agreed at journal 25 Jul, 2025 Reviewers invited by journal 25 Jul, 2025 Editor assigned by journal 24 Jul, 2025 Submission checks completed at journal 24 Jul, 2025 First submitted to journal 24 Jul, 2025 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-7201833","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":491458955,"identity":"14cd160f-4f0d-4562-86e5-05c8257e5ce2","order_by":0,"name":"Joel Silas S","email":"","orcid":"","institution":"National Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Joel","middleName":"Silas","lastName":"S","suffix":""},{"id":491458956,"identity":"536865ff-a3b8-4684-9ffb-cce7c6aa326d","order_by":1,"name":"Mariappan V","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAoklEQVRIiWNgGAWjYLCChAoGHjCDh3gtZxh4eNhI0sLYBlRNtBaDa4effXg4746MvXwD44O3bcRouZ1mPCNx2zOQw5gN5xKjRXJ2gjFD4rbDIC1s0rzEaUn/zJA4B6yF/TdRWvilc4C2NEBsYSZWSzFDwjGglmOJzZJzzhGhhU06fTPjj5rD9uzNhw9+eFNGhBYkwNhAmvpRMApGwSgYBbgBAEICLUfw/Z2xAAAAAElFTkSuQmCC","orcid":"","institution":"National Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"Mariappan","middleName":"","lastName":"V","suffix":""},{"id":491458957,"identity":"fcc7c9f2-75b4-4e44-8e72-ec6e162cbb60","order_by":2,"name":"Arun M","email":"","orcid":"","institution":"National Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Arun","middleName":"","lastName":"M","suffix":""},{"id":491458958,"identity":"0e22d879-786f-4ab4-a508-c5e8747d4ffc","order_by":3,"name":"Karthikeyan K","email":"","orcid":"","institution":"National Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Karthikeyan","middleName":"","lastName":"K","suffix":""}],"badges":[],"createdAt":"2025-07-24 05:53:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7201833/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7201833/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10765-025-03662-x","type":"published","date":"2025-10-27T15:57:13+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":87755794,"identity":"0d0a07c0-9f7c-4106-b98b-f59dfc105cb5","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":243482,"visible":true,"origin":"","legend":"\u003cp\u003ePhotograph of samples\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/c6cbbba0af1cf32642c5a4c1.png"},{"id":87755795,"identity":"2fdbb042-a7a1-4e27-b048-ac953f134cf2","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":326316,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCharging and discharging setup\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/86dc537fd828a8a3bc35dbe2.png"},{"id":87755797,"identity":"780e72be-0a5d-453a-99b8-6a48c42ff647","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":175010,"visible":true,"origin":"","legend":"\u003cp\u003eSEM image of BN\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/d6cc8009a4c8268b119d5b33.png"},{"id":87756706,"identity":"072e3dc5-df13-4e1c-b6f7-34f6f3e17d0c","added_by":"auto","created_at":"2025-07-28 16:07:56","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":48121,"visible":true,"origin":"","legend":"\u003cp\u003eParticle size distribution of BN\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/c8a654ca9dd3b0ae44b80383.png"},{"id":87755803,"identity":"9a5a82cb-437f-49d3-8ab0-899c184c7929","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":23493,"visible":true,"origin":"","legend":"\u003cp\u003eXRD graph of BN\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/06ced2fccbe799456be46b26.png"},{"id":87755804,"identity":"44b1bd1a-19a4-40a5-a58e-fb3364286a07","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":78431,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR results of the PCMs, CL-CA, and NEPCMS\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/938329841892b7872b5c5e85.png"},{"id":87756547,"identity":"7e21d5be-ae78-4206-96e7-3409725efe83","added_by":"auto","created_at":"2025-07-28 15:59:56","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":53144,"visible":true,"origin":"","legend":"\u003cp\u003eDSC Melting Plot\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/9119ec7650ac090254814610.png"},{"id":87756544,"identity":"1697c02b-d917-4ed7-a7ab-93020954a94a","added_by":"auto","created_at":"2025-07-28 15:59:55","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":49678,"visible":true,"origin":"","legend":"\u003cp\u003eDSC Freezing plot\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/0b82fd19b8c51e98f2b24c67.png"},{"id":87756546,"identity":"53353eb0-23e1-49af-b206-d98340d5295d","added_by":"auto","created_at":"2025-07-28 15:59:56","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":44482,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThermal conductivity of samples\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/cbc84af5428fc0e65318ea4e.png"},{"id":87755818,"identity":"87aa71b3-9dc8-4127-a4c2-910d8c367e42","added_by":"auto","created_at":"2025-07-28 15:51:56","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":236408,"visible":true,"origin":"","legend":"\u003cp\u003eThermal cycling chamber\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/694ca0a9b9b73a9f391b8470.png"},{"id":87755810,"identity":"2a79f381-a6c5-40ae-84ff-eb9ee535da42","added_by":"auto","created_at":"2025-07-28 15:51:55","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":64016,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea) Charging and b) discharging graph of CL-CA binary mixture and 2% BN\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/9bfcc930533cddc63d5965f3.png"},{"id":95039909,"identity":"9a5b569f-ac43-44f1-ab82-2110ed02a130","added_by":"auto","created_at":"2025-11-03 16:05:27","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2198241,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7201833/v1/88c45a3e-52aa-4444-bba3-b5225bda05e6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Characterization and experimental study on novel nano-enhanced binary phase change material for cold chain logistics","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eThe immune system is being improved by vaccines, which help us to fight against bacteria and viruses. The vaccine box usually maintains a specified temperature range inside it to store, transport, and preserve the vaccine. Otherwise, the vaccine loses its potency, fails to protect against disease, and results in an inadequate immune response[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. To control the temperature of the vaccine storage cabin, passive cooling is employed as active cooling consumes more energy. Passive cooling achieves temperature regulation through PCMs and appropriate insulation material. PCMs are substances used for storing energy by absorbing and releasing heat[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. When a substance transitions from solid to liquid, or liquid to solid thermal energy is transferred [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The current study focuses on fatty acid-based binary PCMs as it offers advantages like congruent melting, chemical stability, non-toxicity, cost-efficiency, and phase transition in the required temperature range but less thermal conductivity[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. To avoid the low thermal conductivity of PCM foreign particles like nanoparticles, nanotubes, nanofibers, and nanosheets have been added to the PCM to improve its thermal conductivity. The added nanoparticles act as a nucleating agent and enable a congruent phase change process in CPCMs (Composite phase change material). Numerous methods have been employed by prior researchers to add the nanoparticles to PCM like vacuum impregnation, varnish layer, autoclave, stirring, ultrasonication, and kneader mixing technique. Then the PCMs thermal conductivity is assessed using the laser flash method, transient plane source method, transient state method and transient hot wire method[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. 1-Dodecanol and caprylic acid eutectic mixture had a H\u003csub\u003em\u003c/sub\u003e of 171.06 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and a T\u003csub\u003em\u003c/sub\u003e of 6.52\u0026deg;C was found to retain its enthalpy even after 60 and 120 thermal cycles[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. A Binary mixture of n-octanoic acid and myristic acid was prepared with a weight ratio of 87:13 and 7 weight % EG was added to improve the thermal conductivity of the mixture and was reported as 0.9975 W.m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e which was 235.75 % more than that of te base sample, its melting point and H\u003csub\u003em\u003c/sub\u003e was 6.8\u0026deg;C and 136.3 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The thermal conductivity of Caprylic acid was improved when adding 0.5 weight % of synthesized nanoparticles like CuO, Ag, ZnO, and GO by 36%, 52%, 43%, and 87% respectively[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Two commercial PCMs, namely C-18 and E-21, used in a refrigerator evaporator to minimize the temperature rise in the cabinet, have been encapsulated in a stainless-steel container. Compared to C-18(-12/-7\u0026deg;C), the air temperature was maintained at a lower temperature(-16/-12\u0026deg;C) when E-21 was used as PCM [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Three nanoparticles namely nano copper, nano silver, and graphene, were added to magnesium nitrate hexahydrate with a thickening agent carboxy methyl cellulose. By adding nanoparticle with 0.5, 1 and 1.5 weight percentages, there was an improvement in thermal conductivity of the base PCM. Upon adding graphene in 0.5, 1, and 1.5 weight percentages, there was an increase in thermal conductivity of 92.43%, 107.5%, and 138.4% with respect to the base PCM[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. A composite PCM was prepared by using a eutectic salt solution and modified expanded graphite. The modified expanded graphite was prepared by coating SiO\u003csub\u003e2\u003c/sub\u003e on the expanded graphite surface. The prepared form stable PCM has a T\u003csub\u003em\u003c/sub\u003e of -5.6\u0026deg;C and an H\u003csub\u003em\u003c/sub\u003e of 180.8 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Thermal conductivities of the eutectic salt PCM and the modified PCM were 0.575 W m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 5.183 W.m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, confirming eight times increase in thermal conductivity[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. There are very few works on melting points ranging from 2\u0026ndash;8\u0026deg;C for vaccine storage applications, which creates more interest in finding a PCM with a good latent heat with improved thermal conductivity. In this study, novel NEPCMs consisting of CL-CA binary mixture as PCM and incorporating BN nanoparticles of 0.5%,1%,1.5%, and 2% weight percentages to the CL-CA binary mixture have been prepared to cater the needs of the vaccine storage and transportation industry. To the best of the author\u0026rsquo;s knowledge, there are no prior studies reporting the incorporation of BN nanoparticles into CL-CA for the improvement of thermal conductivity.\u003c/p\u003e"},{"header":"2. Materials and Experimentation","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1 Preparation of CL-CA binary mixture and NEPCMs\u003c/h2\u003e\n \u003cp\u003eCL, CA, and BN nanoparticles were procured from Sisco Research Laboratory Pvt. Ltd., India. All materials used in this study were used without further purification. The NEPCMs were prepared in two steps. First, mechanical stirring was done to guarantee proper mixing of PCM, followed by ultrasonication to promote homogenous dispersion. To achieve the application temperature of 2\u0026ndash;8\u0026deg;C, a CL-CA binary mixture was prepared, consisting of two PCMs weighed separately in a ratio of 58:42. The CL-CA binary mixture was heated to 60\u0026deg;C and stirred at 600 rpm for 1 hour using a thermostatic magnetic stirrer and then exposed to ultrasonication at 60\u0026deg;C for 30 minutes. Four Different NEPCMs were prepared by adding nanoparticles in 0.5, 1, 1.5, and 2% weight percentages to the CL-CA binary mixture by stirring and ultrasonication procedure. After this procedure, the prepared samples were naturally cooled to obtain NEPCMs. Figure \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. depicts the image of the prepared samples namely CL,CA,CLCA(58:42),0.5% BN,1% BN,1.5% BN and 2%BN.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2 Experimentation\u003c/h2\u003e\n \u003cp\u003eA transient experiment was conducted to evaluate the heat transfer performance of the prepared binary mixture and 2% BN. A 50 mL spherical flask was taken and filled up to 90% of its volume with two samples. The chiller was filled with a 60:40 water-ethylene glycol ratio and this was used as heat transfer fluid (HTF). The HTF level was made above the PCM level for better heat transfer. A small hole was drilled in the cork for inserting the K-type thermocouple. For the charging behavior of the samples, the chiller was set to a temperature of -8\u0026deg;C, and the samples were immersed in the chiller along with a calibrated K-type thermocouple which is shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e. Based on the calibration, it can be inferred that the temperature is accurate within \u0026plusmn;\u0026thinsp;0.34\u0026deg;C. The thermocouple is connected to a data acquisition system, DAQ 970A KEYSIGHT, with an accuracy of \u0026plusmn;\u0026thinsp;0.9\u0026deg;C and the data was logged for every 5 seconds. The experiment was conducted twice to assess the reproducibility. For the Discharging process, first, the sample was frozen in a separate freezer and then immersed in the chiller with a set temperature of 25\u0026deg;C.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results and discussion","content":"\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Morphology of nanoparticle\u003c/h2\u003e\u003cp\u003eThe SEM (Scanning electron microscope) image taken by Carel zeiss EVO 18 reveals the boron nitride nanoparticle to be of a crystalline hexagonal layered structure. Strong covalent connections bind the atoms of boron and nitrogen within each layer, while weak van der Waals forces bind the layers together. The SEM image shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e with a diameter of 138.6 nm[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] and an average particle size of 70 nm as reported in [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Particle size distribution of nanoparticle\u003c/h2\u003e\u003cp\u003eThe particle size analyzer is used to determine the size distribution of a suspension, a powder, and an emulsion based on light diffraction. The particle size distribution curve is in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The obtained results were similar to [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. The BN had an average particle size of 70nm, a specific surface area of 19.4 m\u003csup\u003e2\u003c/sup\u003eg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, a density of 2.26 g cm\u003csup\u003e\u0026minus;\u0026thinsp;3,\u003c/sup\u003e and a diameter of 138.6 nm. The Particle size distribution of (D10%), (D50%), and D (90%) were 73.20 nm,141.10 nm, and 283 nm, respectively.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e3.3 X-ray Diffraction analysis of nanoparticle\u003c/h2\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe crystalline structure of the nanoparticle is ascertained employing the X-ray diffraction (XRD) method. The XRD pattern was obtained using Ultima IV unit (Make: Rigaku) emitting Cu-Kα radiation with a wavelength (λ) of 1.5406 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\AA\\:\\:\\)\u003c/span\u003e\u003c/span\u003e operated at 30 mA of beam current and 40 kV of accelerating voltage. The diffraction pattern of BN is collected in the 2θ ranging from 10 \u0026deg; to 90\u0026deg;, for a step size of 0.05\u0026deg; with a scanning rate of 1\u0026deg;min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. This is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. The crystal system of the BN nanoparticle was determined to be hexagonal in shape with lattice constants a\u0026thinsp;=\u0026thinsp;2.51 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\AA\\:\\)\u003c/span\u003e\u003c/span\u003e, b\u0026thinsp;=\u0026thinsp;2.51 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\AA\\:,\\)\u003c/span\u003e\u003c/span\u003e and c\u0026thinsp;=\u0026thinsp;6.96 \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\AA\\:\\)\u003c/span\u003e\u003c/span\u003e. There is a strong peak at 2θ\u0026thinsp;=\u0026thinsp;26.62\u0026deg; corresponding to the diffraction plane (002) and weak peaks at 40.41\u0026deg;, 43.75\u0026deg;, 54.84\u0026deg;, 77.29\u0026deg; and 81. 92\u0026deg; corresponding diffraction planes (003), (101), (004), (111), and (112) respectively, which is similar to [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].The XRD pattern of BN agreed with the Joint Committee on Powder Diffraction Standards (JCPDS) reference code 96-101-0331.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\u003ch2\u003e3.4 Spectroscopic analysis of the samples\u003c/h2\u003e\u003cp\u003eFT-IR analysis was done to find the chemical stability of the NEPCMs and to determine the PCMs functional group. An investigation using was conducted using a perkin elmer spectrum two, FT-IR spectrometer equipped with LiTaO3 detector, having a resolution of 2 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 8 scans. The resulting spectra are illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e. This test was performed to evaluate the chemical stabilities of the CL-CA binary mixture containing boron nitride nanoparticles. The existence of the carboxyl group of CA is shown by the stretching vibration at 1706 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e which is attributed to the C\u0026thinsp;=\u0026thinsp;O group. The peaks present in the wavenumber 2857 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 2952 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e are due to the CH\u003csub\u003e2\u003c/sub\u003e and CH\u003csub\u003e3\u003c/sub\u003e alkane groups. This result was found to agree with [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The three peaks at 2956.25 cm \u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 2925cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 2857 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e confirm the CH\u003csub\u003e3\u003c/sub\u003e and CH\u003csub\u003e2\u003c/sub\u003e stretching of the alkane group in the CL and a knife-like peak at 1706.08 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e attributed to ‒C\u0026thinsp;=\u0026thinsp;O of the carboxylic acid group, the peaks were in line with[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eNEPCMs did not exhibit any extra absorption peaks, indicating that surface tension and capillary action were the main factors influencing the CL-CA binary mixture and nanoparticles[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].The nano enhanced PCM was formed only by physical mixing without changing the structure of CL-CA binary mixture. It can be observed that all the major peaks present in the FTIR spectra of the thermally cycled PCM samples were identical to those in the spectra of the uncycled PCM sample.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e3.5 Phase transition analysis of NEPCMs\u003c/h2\u003e\u003cp\u003eThe enthalpy and melting point of the NEPCMs were determined by the DSC test. Setaram instrument, which has an accuracy of \u0026plusmn;\u0026thinsp;0.8% and a precision of 2.5%, was used to take the enthalpy values of the samples. The samples were loaded in an alumina crucible and were subjected to a heating and cooling rate of 2\u0026deg;Cmin\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e at a temperature range of -15\u0026deg;C to 40\u0026deg;C with inert nitrogen. The T\u003csub\u003em\u003c/sub\u003e and T\u003csub\u003ef\u003c/sub\u003e (freezing temperature) of pure capric acid was found to be 30.914\u0026deg;C and 26. 94\u0026deg;C.The H\u003csub\u003em\u003c/sub\u003e and H\u003csub\u003ef\u003c/sub\u003e (freezing enthalpy) of capric acid were found to be 135 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 134.55 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1;\u003c/sup\u003e furthermore, T\u003csub\u003em\u003c/sub\u003e and T\u003csub\u003ef\u003c/sub\u003e of pure caprylic acid were 16.20\u0026deg;C and 12.11\u0026deg;C. The H\u003csub\u003em\u003c/sub\u003e and H\u003csub\u003ef\u003c/sub\u003e were 141.46 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 134.55 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The DSC plot depicts the peak melting point of the CL-CA binary mixture as 7.66\u0026deg;C and its H\u003csub\u003em\u003c/sub\u003e as 119.07 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The melting and freezing DSC curves are in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e. The DSC results of the prepared binary mixture revealed that the melting point was consistent with the previous study [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The H\u003csub\u003ef\u003c/sub\u003e for the binary mixture was found to be 119.44 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The percentage decrease in H\u003csub\u003em\u003c/sub\u003e of nano-enhanced PCM with respect to the binary mixture was found to be 4.5%, 5.6%, 10.7%, and 19.4% respectively.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eAfter 100 thermal cycles again DSC test was performed again for 2 samples, CL: CA binary mixture and 2% BN and there was a slight decrease in both H\u003csub\u003em\u003c/sub\u003e and H\u003csub\u003ef\u003c/sub\u003e. The H\u003csub\u003em\u003c/sub\u003e and H\u003csub\u003ef\u003c/sub\u003e for CL- CA binary mixture came out to be 103.19 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 102.78 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The H\u003csub\u003em\u003c/sub\u003e and H\u003csub\u003ef\u003c/sub\u003e for 2% BN is 93.89 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 91.23 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. After thermal cycling, the percentage decrease of Hm for CL: CA binary mixture is 13.33% and that of 2% BN is 2.16%. Three heating and cooling cycles were performed, and the average values are reported.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.6 Thermal conductivity assessment of samples\u003c/h2\u003e\u003cp\u003eThe prepared samples' thermal conductivities were measured using thermtest measurement platform, MP-2 portable meter using a transient hot wire L3 sensor which has a measuring range of 0.1-1 Wm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eK\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and an accuracy of 5%.The transient hot wire sensor is a wire that is suspended between two contact points and is inserted in the test cell which can hold 20 mL of the sample with a stabilization of 10s and a test time of 1s. The heat transfer efficiency and speed of heat transfer are determined by thermal conductivity. The thermal conductivities of the pure sample CL, CA and CL-CA binary mixture were 0.151W.m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e,0.153 Wm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 0.148 Wm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e individually. This can be seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e. The percentage increase for 0.5%, 1%, 1.5%, and 2% weight percentage BN in comparison to the binary mixture of CL-CA were 3.3%, 4.7%, 10.1%, and 12.1%. This is because nanoparticles are smaller in size and have high aspect ratio which causes intermolecular interaction and Brownian motion within the base PCM [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. After thermal cycling the thermal conductivity test was done for 2 samples CL: CA(58:42) and 2% BN respectively. There is a 0.67 % nd 1.8% decrease for CL-CA binary mixture and 2% BN respectively.The reported thermal conductivity values are taken thrice and averaged value is reported.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.7 Thermal cycling tests\u003c/h2\u003e\u003cp\u003eTo evaluate the thermal reliability of the prepared Nano-Enhanced Phase Change Materials (NEPCMs), the samples were subjected to repeated thermal cycling using a programmable thermal cycling chamber (model DQ-TC-002, Make: Digiqual Systems) with a 30-liter capacity[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] which is depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e. The chamber is equipped with sample trays and a PID-controlled system for precise temperature regulation. The NEPCM samples, each weighing 30 grams and contained in 100 mL beakers, were exposed to a temperature range of \u0026minus;\u0026thinsp;15\u0026deg;C to 15\u0026deg;C for a total of 100 continuous thermal cyclesI.Initially, the chamber was cooled to -15\u0026deg;C to stabilize the sample at the starting temperature. Each thermal cycle involved heating the sample from \u0026minus;\u0026thinsp;15\u0026deg;C to 15\u0026deg;C holding at 15\u0026deg;C for 15 min, and subsequently cooling it back to -15\u0026deg;C. Following the cycling process, the samples were analyzed using Differential Scanning Calorimetry (DSC), thermal conductivity measurements, and Fourier Transform Infrared Spectroscopy (FTIR) to assess changes in thermal performance and structural stability.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e3.8 Charging and discharging curve\u003c/h2\u003e\u003cp\u003eThe graph is plotted between time and temperature. We can observe from the graph Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003ea) that there is sensible cooling from 0 to 10 minute(min) and 0 to 15min for CL: CA (58:42) and 2% BN, respectively. In this phase, heat is extracted as the PCM cools. Then there is phase change happening where the heat is released as the PCM solidifies which is represented from the 10th min to 65 min for the binary mixture and 15 min to 52 min for 2% BN, then again sensible cooling phase which happens from 65th min to 140 min and 52 min to 138 min for CL-CA binary mixture and 2% BN respectively. The nanoparticle enhanced PCM reached low temperature more rapidly than the binary mixture. This behavior suggests that the presence of nanoparticle promotes faster nucleation and solidification. In the discharging phase for CL-CA binary mixture there is 0 to 7th min and phase change from 7 to 17th min and again sensible heating from 17th to 25th min. For 2% BN there is sensible heating from 0 to 5th min as the temperature rises rapidly because it absorbed heat more quickly. Then phase change from 5th to 11th min and again there is sensible heating from 11 to 24th min for 2% BN which is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003eb). The smoother temperature rise of 2% BN during melting implies uniform heat absorption, potentially indicating enhanced thermal dissipation enabled by nanoparticles. The rate of charging and discharging, and the duration of phase change, are important to evaluate the feasibility of phase change materials.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"4.Conclusion","content":"\u003cp\u003eIn conclusion, the prepared novel NEPCMs have excellent potential for vaccine storage and transportation applications as it has the T\u003csub\u003em\u003c/sub\u003e in the range of 2\u0026ndash;8\u0026deg;C.The following conclusions were drawn from the above characterization The binary PCM mixture has T\u003csub\u003em\u003c/sub\u003e = 7.66\u0026deg;C, T\u003csub\u003ef\u003c/sub\u003e = -0.984\u0026deg;C, and phase change enthalpies H\u003csub\u003em\u003c/sub\u003e =119.07 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and H\u003csub\u003ef\u003c/sub\u003e =119.44 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. For 2% of BN in the binary mixture, the phase change temperatures of T\u003csub\u003em\u003c/sub\u003e=7.24\u0026deg;C and T\u003csub\u003ef\u003c/sub\u003e=1.033\u0026deg;C and phase change enthalpies were H\u003csub\u003em\u003c/sub\u003e= 95.96 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, H\u003csub\u003ef\u003c/sub\u003e =94.91 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The thermal conductivity of the binary mixture is 0.148 Wm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. K\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and for 2% of BN, the thermal conductivity is 0.166 Wm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eK\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e which confirms an increase in thermal conductivity of 12.1%. FT-IR results confirm that there is no new peak formed in the NEPCMs after adding BN, indicating only physical interaction and proving good chemical stability with the CL- CA binary mixture. Based on the thermal cycling results for 100 melting/freezing cycles confirmed that the CL-CA binary mixture and 2% BN is stable and can be used as a potential material for the cooling application.\u003c/p\u003e\u003cp\u003eThe results indicate that the prepared sample exhibits favorable properties during both melting and freezing, making it a promising candidate for efficient low-temperature thermal energy storage systems.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJoel Silas S: Conceptualization, Methodology, and Writing. Mariappan V: Investigation and Supervision. Arun M: Methodology, Data Curation, and Review. Karthikeyan K: Software and writing.\u003c/p\u003e\u003ch2\u003eAcknowledgments\u003c/h2\u003e\u003cp\u003eNo specific grant from a public, private, or nonprofit funding organization was obtained for this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eA. K. Ray, S. Singh, D. Rakshit, and Udayraj, Thermal Science and Engineering Progress \u003cstrong\u003e27\u003c/strong\u003e, (2022).\u003c/li\u003e\n \u003cli\u003eS. Mo, L. He, L. Jia, Y. Chen, and Z. Cheng, Int J Thermophys \u003cstrong\u003e41\u003c/strong\u003e, (2020).\u003c/li\u003e\n \u003cli\u003eZ. Younsi, L. Zalewski, S. Lassue, D. R. Rousse, and A. Joulin, Int J Thermophys \u003cstrong\u003e32\u003c/strong\u003e, 674 (2011).\u003c/li\u003e\n \u003cli\u003eJ. R. Vennapusa, A. Konala, P. Dixit, and S. Chattopadhyay, Mater Chem Phys \u003cstrong\u003e253\u003c/strong\u003e, (2020).\u003c/li\u003e\n \u003cli\u003eD. Kim, J. Jung, Y. Kim, M. Lee, J. Seo, and S. B. Khan, Int J Heat Mass Transf \u003cstrong\u003e95\u003c/strong\u003e, 735 (2016).\u003c/li\u003e\n \u003cli\u003eK. Karthikeyan, V. Mariappan, P. Kalidoss, R. Anish, P. Sarafoji, J. Venkatanageswara Reddy, and T. Kumar Satpathy, Mater Lett \u003cstrong\u003e328\u003c/strong\u003e, (2022).\u003c/li\u003e\n \u003cli\u003eB. Eanest Jebasingh and A. Valan Arasu, Energy Storage Mater \u003cstrong\u003e24\u003c/strong\u003e, 52 (2020).\u003c/li\u003e\n \u003cli\u003eJ. Zuo, W. Li, and L. Weng, Energy Build \u003cstrong\u003e43\u003c/strong\u003e, 207 (2011).\u003c/li\u003e\n \u003cli\u003eY. Wang, X. Zhang, J. Ji, Y. Li, J. M. Munyalo, B. Liu, X. Xu, and S. Liu, J Mol Liq \u003cstrong\u003e288\u003c/strong\u003e, (2019).\u003c/li\u003e\n \u003cli\u003eP. Sivasamy, S. Harikrishnan, R. Jayavel, S. I. Hussain, S. Kalaiselvam, and L. Lu, Mater Res Express \u003cstrong\u003e6\u003c/strong\u003e, (2019).\u003c/li\u003e\n \u003cli\u003eE. Or\u0026oacute;, L. Mir\u0026oacute;, M. M. Farid, and L. F. Cabeza, in \u003cem\u003eInternational Journal of Refrigeration\u003c/em\u003e (2012), pp. 1709\u0026ndash;1714.\u003c/li\u003e\n \u003cli\u003eH. Wang, L. Guo, K. Liu, Z. Song, L. Wu, M. Fang, and J. Li, Mater Res Express \u003cstrong\u003e6\u003c/strong\u003e, (2019).\u003c/li\u003e\n \u003cli\u003eX. Chen, Y. Fang, Z. Zhang, X. Gao, and J. Niu, International Journal of Refrigeration \u003cstrong\u003e160\u003c/strong\u003e, 402 (2024).\u003c/li\u003e\n \u003cli\u003eF. Kar, C. Hacıoğlu, Y. G\u0026ouml;nc\u0026uuml;, İ. S\u0026ouml;ğ\u0026uuml;t, H. Şenturk, D. Burukoğlu D\u0026ouml;nmez, G. Kanbak, and N. Ay, J Clust Sci \u003cstrong\u003e32\u003c/strong\u003e, 517 (2021).\u003c/li\u003e\n \u003cli\u003eR. Naresh Muthu, S. Rajashabala, and R. Kannan, Renew Energy \u003cstrong\u003e85\u003c/strong\u003e, 387 (2016).\u003c/li\u003e\n \u003cli\u003eK. Karthikeyan, V. Mariappan, P. Kalidoss, J. Mohana Jai Ganesh, P. V. R. Nanda Kishore, S. Prathiban, and R. Anish, J Energy Storage \u003cstrong\u003e74\u003c/strong\u003e, (2023).\u003c/li\u003e\n \u003cli\u003eS. Zhang, X. Zhang, X. Xu, and Y. Zhao, (n.d.).\u003c/li\u003e\n \u003cli\u003eV. Santhosh Reddy, S. Venkatachalapathy, and P. Kalidoss, Energy Sources, Part A: Recovery, Utilization and Environmental Effects \u003cstrong\u003e45\u003c/strong\u003e, 1424 (2023).\u003c/li\u003e\n\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":"international-journal-of-thermophysics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ijot","sideBox":"Learn more about [International Journal of Thermophysics](http://link.springer.com/journal/10765)","snPcode":"10765","submissionUrl":"https://submission.nature.com/new-submission/10765/3","title":"International Journal of Thermophysics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Thermal conductivity, Boron nitride, Phase change material, Latent heat, Nano enhanced Phase change materials","lastPublishedDoi":"10.21203/rs.3.rs-7201833/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7201833/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eNovel nano-enhanced phase change materials (NEPCMs) for vaccine storage applications have been developed for vaccine transportation. Phase change materials(PCMs) are highly regarded due to their excellent heat storage capacities and their ability to operate within a limited temperature range. Nonetheless, their low thermal conductivity restricts their applicability. A binary mixture of caprylic acid (CL) and capric acid (CA) with a weight fraction of 58:42 was developed for the passive cooling application. The CL-CA binary mixture exhibits a melting enthalpy (H\u003csub\u003em\u003c/sub\u003e) of 119.07 Jg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and a melting temperature (T\u003csub\u003em\u003c/sub\u003e) of 7.66\u0026deg;C. Boron nitride (BN) was used as a thermal conductivity enhancer for the above binary mixture. BN was added in various weight percentages of 0.5%, 1%, 1.5%, and 2% in the binary mixture to develop NEPCMs. There was an improvement of 12.1% in thermal conductivity for 2% BN from the base binary mixture. Furthermore, thermal cycling has been done and the samples have maintained stability and phase change characteristics as confirmed using FTIR (Fourier transform infrared spectroscopy), thermal conductivity, and DSC (Differential scanning calorimetry).\u003c/p\u003e","manuscriptTitle":"Characterization and experimental study on novel nano-enhanced binary phase change material for cold chain logistics","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-28 15:51:51","doi":"10.21203/rs.3.rs-7201833/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-19T17:22:51+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-19T17:14:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"256911964937457820560462548979084609759","date":"2025-08-12T03:22:54+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-28T10:15:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"98109641251204305818191355381385688294","date":"2025-07-27T10:31:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"203437036836284759477825307878515171219","date":"2025-07-25T13:45:55+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-25T06:00:19+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-24T14:35:10+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-24T14:33:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Journal of Thermophysics","date":"2025-07-24T05:42:18+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-thermophysics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ijot","sideBox":"Learn more about [International Journal of Thermophysics](http://link.springer.com/journal/10765)","snPcode":"10765","submissionUrl":"https://submission.nature.com/new-submission/10765/3","title":"International Journal of Thermophysics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"e5d4d74d-cdcd-4350-ba28-89af753f042b","owner":[],"postedDate":"July 28th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-03T16:00:18+00:00","versionOfRecord":{"articleIdentity":"rs-7201833","link":"https://doi.org/10.1007/s10765-025-03662-x","journal":{"identity":"international-journal-of-thermophysics","isVorOnly":false,"title":"International Journal of Thermophysics"},"publishedOn":"2025-10-27 15:57:13","publishedOnDateReadable":"October 27th, 2025"},"versionCreatedAt":"2025-07-28 15:51:51","video":"","vorDoi":"10.1007/s10765-025-03662-x","vorDoiUrl":"https://doi.org/10.1007/s10765-025-03662-x","workflowStages":[]},"version":"v1","identity":"rs-7201833","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7201833","identity":"rs-7201833","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}