SEBS/石蜡聚合物基定型相变材料自修复过程热质传递特性研究

Composite phase change materials(PCMs) prepared by physical adsorption method through porous substrate and microcapsule method need for compression molding after preparation. In addition, as the molding intensity is relatively low and its mechanical property is not good. Therefore, preparation of form-stable PCMs with high latent heat and good mechanical property by one-step molding technology need to be studied. This project selects SEBS thermoplastic elastomer (TPE) as supporting materials and paraffin as PCM to prepare the SEBS/paraffin polymer based form-stable PCMs by hot pressing method. The preliminary experiment found that this materials have self-healing function，but the thermal environment of self-healing process is undefined. This project aims at revealing the mass transfer characteristics of the polymer based form-stable PCMs in self-healing process by exploring the diffusion process of paraffin in the polymer. Moreover, this project plans to study the heat conduction mechanism in the inner polymer based form-stable PCMs to optimize the self-healing process after adding thermal conductive filler to obtain the fitting proportionality coefficient of the influence factors, thus obtains the thermal transfer properties.

多孔基质物理吸附法和微胶囊法制备复合相变材料均需二次压制成型，且成型强度不高，机械性能差。因此，本项目拟选用SEBS热塑性弹性体为基材，石蜡为相变材料，通过平板热压法制备具有高潜热、可一次成型且机械性能优越的SEBS/石蜡聚合物基定型相变材料；预实验中发现，该材料具有自修复功能，但其自修复热条件尚未明晰，本项目拟通过考察自修复过程中石蜡在聚合物中的扩散速率揭示自修复过程的质量传递特性，通过探究添加导热填料后热导率的变化规律揭示自修复过程的热量传递特性进而优化其自修复过程。

本项目针对多孔基质物理吸附法和微胶囊法制备复合相变材料均需二次压制成型，且成型强度不高，机械性能差的问题，选用了SEBS热塑性弹性体为基材，石蜡为相变材料，通过平板热压法制备得到了可自修复、具有高潜热、可一次成型且机械性能优越的SEBS/石蜡聚合物基定型相变材料；探索并优化了平板热压法用于不同聚合物基定型相变材料的制备工艺，探明了影响材料结构与性能的制备条件与优化参数，实现了复合材料的结构调控。通过考察自修复过程中石蜡在聚合物中的扩散速率揭示了自修复过程的质量传递特性；探明了导热增强型聚合物基定型相变材料内部导热机理，揭示了自修复过程的热量传递特性并化了自修复过程。所开发的SEBS/石蜡定型相变材料潜热值高达188.1/J•g-1；2mm厚度的哑铃状样品在拉伸速率为300mm/min时其弹性伸长率可达1160%；石蜡质量分数为85%的SEBS/石蜡在130℃环境下自修复时长仅为35min，添加10%质量分数的Al2O3导热粒子，自修复效率可提高28.6%。所取得的成果，目前在Solar Energy Materials and Solar Cells、Journal of Energy Storage、Journal of Material Science、储能科学与技术等期刊发表高水平论文9篇，其中第一标注4篇，第二标注4篇，第三标注1篇；围绕聚合物基定型相变材料的平板硫化制备方法及其应用申请国家发明专利3项，其中1项已获授权；在本项目的研究过程中，培养了硕士研究生4名，其中1名已毕业。