Facile Preparation of Shape Memory Polyurethanes by Polyurethanes Blending

This article presents a facile preparation method of shape memory polyurethane (SMPU) by polyurethane blending from commercial thermoplastic polyurethane (PUA) with designed polyurethane (PUB). Structure, morphology, and shape memory behaviors of SMPU blends are investigated systematically. The results show that the PUB and PUA are miscible in the SMPU blends. When the PUB content is higher than 40 wt %, the T-g of SMPU blends is adjusted to above room temperature. As the PUA content increases, the PUA phase changes gradually from a droplet-like dispersion phase to continuous soft phase, whereas the PUB phase changes from a continuous hard phase to a droplet-like dispersion hard phase. SMPU blends show good shape memory effect when the PUA is blended with more than 40 wt % PUB. Thus, the commercialization of SMPU can be promoted greatly through the polyurethane blending from the commercial thermoplastic polyurethanes with polyurethane containing higher hard segment content. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4047-4053, 2013