聚醚型聚氨醋性能的影响因素

摘要

采用不同种类的聚醚多元醉、二异氛酸酯和扩链剂为原料合成聚氨酯,讨论了聚醚多元醇的相对分子质量、二异氰酸醋的结构、软硬段比例、二异氰酸酯指数、扩链剂种类及用量对聚氨酯性能的影响.结果表明:采用高相对分子质量的聚醚,聚氨酯的定伸强度、拉伸强度和撕裂强度下降,断裂伸长率提高;聚氨酯的性能随硬段含量的增加而提高;异氰酸酯指数控制在1.01～1.03左右;扩链剂链长越短,聚氨酯的微相分离程度和力学性能越好;聚氨酯性能随1,4-丁二醉用量的增加而提高,达到一定用量时反而下降.%Polyurethane(PU) based on all kinds of polyether-polygol, diisocyanate and chain-extender was prepared;the different influential factors of PU were discussed. The results showed that when the molecular weight of polyether-polygol increased, the hardness,tensile strength and tear resistance decreased but the elongation at break increased; the property of PU increased with the increasing perecentage of hard segment phase;R numerical value was controlled between 1.01 and 1.03;the shorter chain-extender had excellent micro phase separate and mechanical properties. With the amount of BDO incrasing, the performance of PU becomes well, but when the amount of BDO comes to a point it appears reverse.