不同扩链剂对浇注型聚氨酯弹性体的影响

Influence of different chain extenders on casting polyurethane elastomer

以甲苯二异氰酸酯(TDI)和聚四亚甲基二醇(PTMG)为原料合成聚氨酯(PU)预聚体,分别用3,3′–二氯–4,4′–二氨基二苯甲烷(MOCA)和二乙基甲苯二胺(DETDA)为扩链剂制备了一系列聚氨酯弹性体(PUE),研究了扩链系数、掺杂BDO(1,4–丁二醇)以及MOCA与DETDA混用对PUE性能的影响。结果表明:随扩链系数的增加,MOCA–PU和DETDA–PU的强度和模量先增加后减小,断裂伸长率先减小后增大;随BDO用量的增加,MOCA–PU和DETDA–PU的硬度、强度和模量呈下降趋势,断裂伸长率和凝胶时间呈上升趋势;使用混合扩链剂时,提高扩链剂中MOCA含量,DETDA–PU的硬度、拉伸强度和撕裂强度呈下降趋势,断裂伸长率和凝胶时间呈上升趋势。

The polyurethane （PU） prepolymer polytetramethylene glycol （PTMG） as raw materials was synthesized by using toluene diisocyanate （TDI） and A series of polyurethane elastomers （PUE） were prepared by using separately 3,3＇-dichloro-4,4＇-diamino diphenylmethane （MOCA） and diethyl toluenediamine （DETDA） as chain extenders. The influence of the chain extension coefficient, doped BDO （1,4-butanediol） and blending MOCA and DEDTA on the performance of PUE was investigated. The results show that with the increase of the chain extension coefficient, the strength and modulus of MOCA-PU and DETDA-PU first increase and then decrease, and the elongation at break first decreases and then increases; with the increase of BDO amount, the hardness, strength and modulus of MOCA-PU and DETDA-PU exhibit the falling trend, and the elongation at break and gel time exhibit the rising trend; when using the mixed chain extender, with the increase of MOCA content in the chain extender, the hardness, tensile strength and tear strength of DETDA-PU exhibit the falling trend, and the elongation at break and gel time exhibit the rising trend.