Design and Synthesis of Reliable Paraffin/Epoxy Phase Change Materials With Excellent Shape Stability and Working Durability for Thermal Energy Regulation

The preparation of phase change materials (PCMs) with excellent heat storage capacity, shape stability, and working durability is of vital importance for their popularization and application. In this work, a series of form-stable PCMs was prepared via blending diglycidyl ether of bisphenol A (DGEBA), aliphatic anhydride with octadecyl side chains (MNAO), and paraffin together followed by thermal curing. Thanks to the plasticizing effect and self-assembly of paraffin, the crystalline behavior of paraffin and MNAO was hardly limited by the epoxy network, and the latent heat of EP/Pa-50 with 50 wt% paraffin content was high, up to 92.3 J/g. Meanwhile, EP/Pa-50 had a low supercooling extent of 11.0°C. Instead of the significant reduction in other properties of most PCMs after being blended with paraffin, the overall performance of EP/Pa-50 remained good due to the strong intermolecular interactions between paraffin and MNAO (based on their good compatibility) and the reliable epoxy network, and EP/Pa-50 exhibited excellent shape stability without the leakage problem, high thermal stability (remain stable below 170°C) and good mechanical properties (tensile strength up to 10.5 MPa). This work provides a facile strategy to prepare form-stable PCMs, which have promising application prospects in the field of thermal regulation.