Microwave-Induced Shape-Memory Effect of Chemically Crosslinked Moist Poly(vinyl alcohol) Networks

MWs are explored as the driving force for an SMP based on chemically crosslinked moist PVA networks. The samples show rapid shape recovery under MW irradiation, whereas dry samples experience no shape changes when irradiated. This effect is attributed to the heat created by vibrating water molecules inside the samples that supplies the energy required for shape recovery. The rate of recovery rate is affected not only by the water content in the material but also by the applied MW power output. Automatic network analysis, DSC, and DMA are used to study the dielectric, thermal and mechanical properties of the samples. MW-induced shape recovery offers advantages such as high and variable recovery rate and the absence of direct contact between the heating source and the material.