TPEE弹性体的合成及其结构与性能研究

Study on synthesis and structural properties of TPEE

以精对苯二甲酸(PTA)、1,4-丁二醇(BDO)和聚四氢呋喃(PTMEG)为原料,通过直接酯化法制备PTMEG质量分数为20%~60%的不同软硬段比例的TPEE弹性体,对TPEE弹性体的化学结构及性能进行了表征。结果表明:制备的TPEE分子中存在PTMEG结构,且软段PTMEG链段已嵌入硬段链段中;当软段PTMEG质量分数由20%提高到60%时,TPEE弹性体的熔体流动指数(10 min)由18 g升高至36 g,具有较好的流动性能;随着软段PTMEG含量增加,TPEE弹性体的熔点、结晶度降低,结晶度从26.39%逐渐降低至11.81%;TPEE弹性体的热稳定性好,不依赖于软硬段比例的变化;随着软段PTMEG质量分数由20%提高至60%,TPEE弹性体的储能模量逐渐降低,损耗正切值由0.08增至0.14,拉伸强度降低42.9%,弯曲强度降低83.2%,断裂伸长率从332%提高至950%,冲击强度大幅提高。

Using purified terephthalic acid(PTA),1,4-butanediol(BDO)and polytetrahydrofuran(PTMEG)as raw materials,thermoplastic polyester-ether elastomers(TPEE)with different ratios of soft and hard segments containing 20%-60%PTMEG by mass fraction were prepared by direct esterification.The chemical structure and properties of TPEE were characterized.The results showed that the prepared TPEE molecule had PTMEG structure,and the PTMEG soft segment had been embedded in the hard segment;the melt flow index(10 min)of TPEE increased from 18 g to 36 g,indicating a good flow performance,when the mass fraction of PTMEG soft segment was increased from 20%to 60%;the melting point of TPEE decreased and the crystallinity gradually decreased from 26.39%to 11.81%with the increase of PTMEG soft segment content;TPEE had good thermal stability,which did not vary with the ratio of soft and hard segments;and the storage modulus of TPEE gradually decreased,the loss tangent value increased from 0.08 to 0.14,the tensile strength decreased by 42.9%,the bending strength decreased by 83.2%,the elongation at break increased from 332%to 950%,and the impact strength increased significantly with the increase of the mass fraction of PTMEG soft segment from 20%to 60%.