The effects of nanoparticles on morphology and thermal properties of erythritol/polyvinyl alcohol phase change composite fibers

Abstract

Abstract Erythritol (E)/polyvinyl alcohol (PVA) phase change composite fibers in which PVA acts as supporting material and different contents of erythritol act as phase change materials (PCMs) were prepared by electrospinning. The effects of different nanoparticles on fiber morphology and thermal properties of composites were also studied. The morphology and thermal properties were characterized by using scanning electron microscopy (SEM), differential scanning calorimetery (DSC) and a thermal conductivity test, respectively. The results showed E/PVA composite fibers were cylindrical with a smooth surface. The content of erythritol in composites could reach a high of 80 wt% with good shape stability, and a high enthalpy value of 258.9 J/g after 100 thermal cycles. The effects of nanoparticles on composites were mainly embodied in decreasing average fiber diameters (AFDs), phase change temperatures and enthalpies with the increase of particle concentrations, and improving fiber stability and thermal conductivity. Among them, the smallest AFDs (0.56 μm) and the lowest heat loss rate (1.0%) were obtained from composites with 4% nano C and 4% nano Al2O3, respectively. The 4% nano SiO2 composites possessed the best shape stability. In addition, the composites that contains 4% nano carbon could decrease the erythritol’s supercooling of 7.55°C, and showed the highest thermal conductivity of 1.55 W/m·K, which was 167% of E/PVA composites. These results demonstrate that E/PVA composites possess high enthalpy values while they improve shape stability and thermal conductivity.