软硬段对聚氨酯弹性体结构性能的影响

Effect of Hard and Soft Segment on Structure-Property of Thermoplastic Polyurethane Elastomer

采用本体聚合和溶液聚合两种方法,合成了一系列用聚乙二酸丁二醇酯二醇作为软段的聚氨酯弹性体。研究了硬段含量和聚醚添加量对聚氨酯弹性体综合性能的影响。利用红外光谱、热分析、力学性能测试、记忆回弹性能和耐水解老化实验等测试手段对样品进行了表征与分析。结果表明：硬段质量含量为31%~35%时,材料的力学性能较优,形状回复率可以达到75%~85%;软段中聚醚添加量在4%~5%（占软段的质量分数）时,弹性体具有较好的力学性能和耐水解性能。

A series of polyurethane（PU） elastomers based on polybutylene adipate（PBA） as soft segment were synthesized by bulk polymerization and solution polymerization.Their morphologies,shape-memory effect,thermal stability and mechanical properties were analyzed by means of FT-IR spectra,AFM,TGA,tensile tests and hydrolysis stability testing.Polytetramethylene glycol（PTMG） was added into soft segment to get better performance of the specimens.PU shows different performances by chang-（ing） the mol ratio of MDI and BD（hard segment） and the quantity of polyether adding into the soft segment.Results show that better mechanical properties,water resistance and 75%-85% of shape recovery are obtained at 31%-35% of hard segment content and 4%-5% of PTMG content.