端羟基聚丁二烯／聚醚型聚氨酯弹性体的合成与性能

将端羟基聚丁二烯(HTPB)、聚四氢呋喃(PTMG)、二苯甲烷二异氰酸酯和1,4-丁二醇反应制备了聚氨酯弹性体。研究了多元醇质量比、制备方法对弹性体力学性能的影响。实验数据表明,各种方法制备出的聚氨酯弹性体的拉伸和撕裂性能均随HTPB／PTMG质量比增高直线下降。随HTPB／PTMG质量比加大,预聚体法制备的聚氨酯弹性体的力学性能的下降幅度小于改进的一步法,改进的一步法小于原一步法。动态力学性能测试研究表明,HTPB／PTMG质量比的提高使聚氨酯弹性体动态内生热依次降低,微相分离程度减弱。

Synthesis and Properties of HTPB/PTMG Polyurethane Elastomers

Polyurethane (PU) elastomers were prepared using hydroxy-terminated polybutadine (HTPB), polytetramethylene (PTMG), 4,4'-diphenylmethane diisocyanate, and 1,4-dihydroxybu-tane. The effects of HTPB/PTMG mass ratio and preparation methods on the mechanical properties of PUs were studied. The results showed that the tensile and tear strengths decreased with increasing HTPB/PTMG mass ratio. With the increasing of the mass ratio of HTPB/PTMG, the loss of mechanical properties of PU elastomers prepared by prepolymer method is less than that by the improved one-step method,and that of the latter is less than that by the one-step method. Dynamical mechanical properties analysis (DMA) revealed that the heat generation also decreased with increasing HTPB/PTMG mass ratio, and the microphase separation weakened.