Effect of Crosslinking Agent on the Properties of Shape Memory Foam for Footwear

To develop shape memory foam for the insole of footwear, two types of hydrogenated styrene-butadiene random copolymer(HSBR) and ethylene vinyl acetate(EVA) foams were produced, and the effects of content of crosslinking agent on both physical and shape memory properties have been studied. Expansion ratio and permanent deformation of the foams decreased with increasing content of crosslinking agent. The result showed that tear strength and resilience of the foams are independent of the amount of crosslinking agent, but rely heavily on the type of resin within the experimental range. Increasing sulfur ratio of the crosslinking agent increased the shape recovery ratio of the foam, but decreased the shape retention characteristics under compression.