形状记忆聚氨酯的热力学性质

Thermomechanical Properties of Shape Memory Polyruethane

文中对具有形状记忆功能的聚氨酯开展了较为系统的热力学实验,主要包括:材料热膨胀系数测定,不同预应变下材料的冻结和恢复响应,不同温度下材料的应力-应变循环关系和应力松弛实验等。在此基础上,结合材料微结构随温度的变化,对实验结果进行了分析。相关研究结果对了解这类功能材料基本热力学性质和建立与之对应的热力学本构具有一定的意义。

As a new class of functional materials, shape memory polymers （SMPs） are receiving more attentions in recent years. A systematic thermomechanical experiments were performed on shape memory polyurethane, which includes determining the coefficient of thermal expansion （CTE）, the frozen and recovery responses under different pre-strains, the stress-strain cycles and stress relaxation under different temperatures. In order to give a further understanding the testing results, some discussion were taken with consideration of the microstructure of the material at different temperatures. The related work is useful in analyzing the thermomechanical properties of this kind of functional materials and proposing suitable thermomechanical constitutions.