TODI类浇注型聚氨酯弹性体的耐热性能研究

Study on Heat Resistance of TODI-based Casting Polyurethane Elastomer

用3,3'-二甲基-4,4'-联苯二异氰酸酯(TODI)与聚四氢呋喃(PTMG)、聚己内酯多元醇(PCL)合成了一系列浇注型聚氨酯弹性体,考察了不同聚合物多元醇、扩链剂以及硬段含量对弹性体耐热性能和力学性能的影响。结果表明:PCL体系的耐热性能和力学性能优于PTMG体系,其拉伸强度在120℃下保有率>90%;用3,3'-二氯-4,4'-二苯基甲烷二胺(MOCA)扩链时,弹性体的耐热性能明显优于用1,4-丁二醇(BDO)扩链的弹性体;TODI预聚体NCO质量分数为5%左右时,制品具有较高的硬度、较好的耐热性能和力学性能。合成的TODI类聚氨酯弹性体可用于制备高性能密封件和刮片等。

A series of casting polyurethane elastomers were synthesized by using 3,3＇-dimethyl-4,4＇-biphenylene diisocyanate（TODI） with polytetramethylene ether glycol（PTMG）,polycaprolactone polyol（PCL）.The influence of different polymer polyols,chain extenders and hard segment content on heat resistance and mechanical properties of the elastomers was investigated.The results show that the heat resistance and mechanical properties of PCL system are better than those of PTMG system,the retention rate of tensile strength at 120℃ is over 90%;The heat resistance of elastomers using 4,4＇-methylene bis（2-chloroaniline）（MOCA） as chain extender is significantly superior to that of elastomers using 1,4-butanediol（1,4-BDO） as chain extender.The products have higher rigidity,better heat resistance and mechanical properties when the NCO mass fraction in prepolymers based on TODI is about 5%.The synthesized TODI-based polyurethane elastomers are suitable to manufacture high performance seals,blades,etc.