Advances in Shape Memory Polyurethanes and Composites: A Review

Polyurethanes are synthetic smart materials having exquisite property to regain original shape from temporary shape when an external force (heat, light, electricity, and entropy driven deformation) is applied. Shape memory polyurethanes have ability to replace shape memory alloys due to cut-rate, easy manufacturing, programing, and high shape recovery ratio. The review focused on polyurethane types exhibiting shape memory effect and various categories of shape memory effects in polyurethane. Moreover, compound structure, modeling structure, applications, and related synthetic methods for shape memory polyurethanes are discussed. The strategies for induction of cross-linking and post cross-linking at high, medium, and low temperature are surveyed.