EHTPB基黏结剂体系的低温固化

Curing of EHTPB-Based Adhesive Systems at Low Temperature

为了开发适用于PBX浇注炸药低温固化的黏结剂体系,选取环氧端羟基聚丁二烯(EHTPB)为黏结剂,用黏度增长法研究了添加二聚酸二异氰酸酯(DDI)、甲苯二异氰酸酯(TDI)、六亚甲基二异氰酸酯三聚体(HDI trimer)、异佛尔酮二异氰酸酯(IPDI)、二苯基甲烷二异氰酸酯(MDI)5种固化剂在45℃条件下黏度随时间的变化规律;并在35℃下研究体系中添加不同催化剂羰基铜化合物(YKT)、二月桂酸二丁基锡(T12)、三亚乙基二胺(DABCO)、辛酸亚锡(T9)、三苯基铋(TPB)对EHTPB-DDI黏结剂体系的催化反应效果;采用恒温流变技术对EHTPB-DDI-YKT黏结剂体系的固化反应动力学进行了计算。结果表明,在45℃条件下DDI与IPDI的固化反应活性相近,可作为较为理想的固化剂;在35℃下催化剂对EHTPB-DDI固化反应速率的影响顺序为:T12>T9>DABCO>YKT>TPB,其中添加YKT时适用期为5.45 h,符合固化工艺要求;通过反应速率判断出EHTPB-DDI-YKT黏结剂体系固化反应为自催化反应,计算出该黏结剂体系的表观活化能为91.65 kJ/mol,反应级数为0.836。EHTPB-DDI-YKT黏结剂体系能够有效降低黏结剂体系的固化温度,实现EHTPB基PBX浇注炸药低温固化。

In order to develop a binder system suitable for low temperature curing of PBX pouring explosives,epoxy hydroxy-terminated polybutadiene(EHTPB)was selected as binder.The viscosity changes with time at 45℃of 5 kinds of curing agents including dimeric acid diisocyanate(DDI),toluene diisocyanate(TDI),hmethylene diisocyanate trimer(HDI trimer),isophorone diisocyanate(IPDI)and diphenylmethane diisocyanate(MDI)were studied by viscosity growth method.The catalytic reaction effects of copper carbonyl compound(YKT),dibutyltin dilaurate(T12),triethylenediamine(DABCO),stannous caprylate(T9)and triphenylbismuth(TPB)on the EHTPB-DDI binder system were studied at 35℃.The curing reaction kinetics of EHTPB-DDI-YKT binder system was calculated by constant temperature rheological technique.The results show that DDI and IPDI have similar curing activity at 45℃,and both of them can be used as an ideal curing agent.At 35℃,the catalyst influences the curing reaction rate of EHTPB-DDI in the following order:T12>T9>DABCO>YKT>TPB.Besides,the application period of YKT is 5.45 h with YKT added,which meets the curing process requirements.According to the reaction rate,the curing reaction of EHTPB-DDI-YKT binder system is an autocatalytic reaction.It is calculated that the apparent activation energy of the binder system is 91.65 kJ/mol and the reaction order is 0.836.The EHTPB-DDI-YKT binder system can effectively reduce the curing temperature of the binder system and realize the low temperature curing of the EHTPB-based PBX pouring explosive.