采用超声波纵波透射法在线监测了端羟基聚丁二烯/甲苯二异氰酸酯(HTPB/TDI)体系在不同温度下的固化过程,测定了固化过程中超声波的声速与衰减,计算了体系的纵向储能模量和固化度,由此确定了体系的凝胶化、硬化以及固化终点时间。与红外光谱法相比,超声波法通过表征固化体系模量的变化更合理地揭示了体系物理交联和化学交联两方面协同作用的固化机理,对HTPB/TDI体系硬化后的固化过程监测更为灵敏。
A longitudinal ultrasonic transmission method was applied to on-line monitor the curing behaviors of hydroxyl-terminated polybutadiene/toluene diisocyanate(HTPB/TDI) system at different temperature,the velocities and attenuations of longitudinal waves were determined during the whole curing process,and the gelation,vitrification and cure off time were identified based on the longitudinal storage modulus and curing degree of the HTPB/TDI system.Compared to infrared spectroscopy method,the ultrasonic monitoring reveals the curing process more reasonably due to the combination of physical and chemical gelations through the variation of modulus,and it is more sensitive to monitor the curing behavior of HTPB/TDI system after vitrifying.