種々の温度で負荷を受けるポリウレタン系形状記憶ポリマフィルムの形状固定性と形状回復性

抄録

The shape fixity and recoverability in a thin film of shape memory polymer of the polyurethane series were investigated using the thermomechanical cycling tests with loadings at various temperatures. The results are summarized as follows. (1) During the heating process under no load, strain is recovered at temperatures in the vicinity of the glass transition temperature T_g in the case of loadings at T_g and T_g+20K, but in the case of loadings at T_g-20K it is recovered at temperatures in the vicinity of T_mg. (2) The rate of strain recovery is about 98%, except for the early cycles in the case of loadings at T_g and T_g+20K, while it decreases with increasing cycles in the case of loading at T_g-20K. (4) The thermomechanical properties of materials with different T_g are quite alike in spite of the difference in T_g.