Thermomechanical Properties of Polyurethane-Shape Memory Polymer Foam

The thermomechanical properties of polyurethane-shape memory polymer foam were investigated by the compressive tests. The results are summarized as follows. (1) The material contracts uniformly in the axial direction with the ratio of lateral strain to axial strain 0.4 in the early stage, but about 0.15 thereafter. (2) The deformation resistance is large at low temperature and at high strain rate. (3) In the case of thermomechanical loading, strain is recovered at temperatures in the vicinity of T _g . The rate of strain recovery is 99%. The rate of strain fixity is 100%.