Viscoelastic characterization of multifunctional composites incorporated with microencapsulated phase change materials

The paper reports an experimental investigation on the viscoelastic properties of glass/epoxy composites incorporated with microencapsulated phase change materials (micro-PCMs). The effects of phase-transition process on the thermo mechanical characteristics of host composite laminates were studied using dynamic mechanical analysis (DMA) technique. Variation of the storage modulus is explained by the observed changes in the apparent crosslink density. Using the loss modulus to determine the glass transition temperature (Tg), a bilinear dependency between Tg of the composite laminates and micro-PCMs concentration was identified. Glass transition relaxation in composites was studied using multi-frequency DMA scans in conjunction with the apparent activation energy. It was found that the viscoelastic properties of micro-PCMs enhanced glass/epoxy composites are inversely proportional to the weight fraction of microencapsulated fillers.