Microencapsulated phase change materials (PCMs) are being increasingly employed as functional fillers in polymer matrices for thermal management. Therefore, the effect of PCM microcapsules on the rheological, microstructural, thermal and mechanical properties of the host polymer matrices must be understood. This work concerned the preparation of epoxy polymers filled with PCM microcapsules (MC) in various concentrations and their subsequent characterization. The MC phase increases the viscosity of epoxy before curing, thereby reducing castability and hindering elimination of air bubbles. The latter was reflected in an increase in porosity for highly filled compositions, as elucidated by density measurements and microscopic investigation. SEM micrographs showed that the adhesion between the capsule shell and the epoxy matrix was not optimal. The interfacial weakness and the intrinsic low stiffness and strength of MC caused a reduction in mechanical properties, as evidenced by the Nicolais‐Narkis and Pukanszky models. On the other hand, at zero or low deformation levels, the interface presents no gaps and is able to transfer load and heat, as demonstrated by the data of elastic modulus, modeled with the Halpin‐Tsai and Lewis‐Nielsen models, and those of thermal conductivity, in excellent agreement with the Pal model. POLYM. ENG. SCI., 2020. © 2020 Society of Plastics Engineers

中文翻译：

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含石蜡微胶囊的环氧树脂复合材料热力学性能的详细实验和理论研究

微囊化的相变材料（PCM）越来越多地用作热管理聚合物基体中的功能性填料。因此，必须了解PCM微胶囊对主体聚合物基质的流变，微结构，热和机械性能的影响。这项工作涉及填充各种浓度的PCM微胶囊（MC）的环氧聚合物的制备及其后续表征。MC相会增加固化前环氧树脂的粘度，从而降低可浇铸性并阻碍气泡的消除。后者反映为高度填充的组合物的孔隙率增加，如密度测量和显微镜研究所阐明的。SEM显微照片显示胶囊壳和环氧基质之间的粘合不是最佳的。Nicolais-Narkis和Pukanszky模型证明，MC的界面无力以及固有的低刚度和强度导致机械性能下降。另一方面，在零变形水平或低变形水平下，界面没有间隙，并且能够传递载荷和热量，如通过Halpin-Tsai和Lewis-Nielsen模型以及导热性，与Pal模型非常吻合。POLYM。ENG。SCI。，2020.©2020塑料工程师协会 如Halpin-Tsai和Lewis-Nielsen模型所模拟的弹性模量数据以及热导率数据所显示的，与Pal模型极为吻合。POLYM。ENG。SCI。，2020.©2020塑料工程师协会 如通过Halpin-Tsai和Lewis-Nielsen模型建模的弹性模量数据以及热导率数据所示，与Pal模型非常吻合。POLYM。ENG。SCI。，2020.©2020塑料工程师协会