Silk Fibroin-Chitosan Based Phase Change Materials (PCMs): Microcapsule and Foam Structures

Abstract

Phase change materials (PCMs) can store and release latent heat by making phase transitions between solid-solid or liquid-solid phases at specific temperature ranges. In the preparation of silk fibroin (SF) and chitosan (CHI) based phase change microcapsules and foam structures, the usage of virgin coconut oil (VCO) as a phase change agent was investigated, both forms were successfully prepared and characterized. Scanning Electron Microscope (SEM) and optical microscope with heating block analyzes were performed on microcapsules. SEM, Fourier-transform infrared spectroscopy, and differential scanning calorimeter analyzes were performed on foams. SF and CHI-based microcapsules had homogeneous size distribution and were thermally stable up to 60°C. Characteristic properties of the foam structures changed with the amounts of SF and CHI, and phase change occur at around 25°C, the melting temperature of VCO, resulting in energy absorption of 0.5287 W/g. Microcapsule and foam PCMs obtained can be used in different medical and thermoregulated textile applications.