Robust Smart Fabrics Composed of MgO Nanostructures Encapsulated in Hollow Polystyrene Fibers for Efficient Thermoregulation

Functionalized smart fabrics based on phase change materials (PCMs) are potential candidates for adaptive temperature regulation. In this work, composite PCM (CPCM) was first designed with optimized thermophysical properties and antileakage performance. Magnesium oxide (MgO) whiskers were used as the thermal filler to enhance the heat conduction of the CPCM. To improve the compatibility between the filler and the matrix, the whiskers were encapsulated by polystyrene (PS) hollow fibers, forming nanostructured MgO@PS fibers, accompanied by reduced interfacial thermal resistance (ITR). The composite phase change fabric (CPCF) with uniformly distributed internal composition was prepared by the vacuum impregnation method. Owing to the optimized CPCM matrix and specifically designed MgO@PS nanostructure, the final developed fabric (CPCF-M8) showed favorable phase change properties, good stability and mechanical properties, and excellent thermal conductivity of 1.34 W/mK (a 434% improvement compared to the original CPCM). The efficient thermoregulation capability of the CPCF-M8 was further confirmed by performing the practical human thermal management tests with a maximum temperature adjustment of 2.3 °C. In addition, the outdoor temperature adaption tests revealed that the CPCF-M8 was able to provide self-cooling and self-heating, resulting in a maximum 4.2 °C temperature adjustment.