聚氨酯弹性体的合成与耐热性能研究

Study on the Synthesis and Heat Resistance of Polyurethane Elastomer

分别以聚己内酯二醇(PCL)、聚四亚甲基醚二醇(PTMG)为低聚物二醇原料,以对苯二异氰酸酯(PPDI)、二苯基甲烷二异氰酸酯(MDI)或2,4-甲苯二异氰酸酯(TDI)为异氰酸酯原料,以1,4-丁二醇(BDO)或3,3'-二氯-4,4'-二氨基二苯基甲烷(MOCA)为扩链剂,采用预聚体法合成了结构不同的聚氨酯(PU)弹性体,并对其进行了物理机械性能测试、热重分析(TG)和动态力学分析(DMA)。结果表明,PCL/PPDI/BDO聚氨酯弹性体的力学性能和耐热性能最好; PPDI/BDO/PCL聚氨酯弹性体的储能模量优于TDI/MOCA/PCL弹性体;当硬段结构为PPDI/BDO时,较低温度下,PCL体系的储能模量优于PTMG体系,较高温度下,PTMG体系优于PCL体系。

The polyurethane elastomers(PU)were synthesized by prepolymer method,using polycaprolactone glycol(PCL)or polytetramethylene ether glycol(PTMG)as oligomer diol,p-phenylene diisocyanate(PPDI),diphenylmethane diisocyanate(MDI)or toluene diisocyanate(TDI)as isocyanate,1,4-butanediol(BDO)or3,3′-dichloro-4,4′-diaminodiphenylmethane(MOCA)as chain extender respectively.The mechanics properties were tested.The heat resistance was studied using thermogravimetric analyzer(TG)and dynamic mechanical analyzer(DMA).The results showed that,when PPDI/BDO was selected as hard segment,the mechanics properties and heat resistance of PCL system were better than PTMG system.When PCL was selected as polyol,the mechanics properties and heat resistance of PPDI/BDO system were the best.The storage modulus of PPDI/BDO/PCL system were prior to TDI/MOCA/PCL system.When PPDI/BDO was selected as hard segment,the storage modulus of PCL system was superior to PTMG system at low temperature,but inferior to PTMG system at higher temperature.