【摘要】 目的 研究胶黏剂的固化程度及在自然贮存和温度循环中的变化。方法 利用低场核磁共振技术，通过测定胶黏剂中氢原子在固化和老化过程中横向弛豫时间T2的变化，反映固化过程中交联结构的发展，以及交联结构在6个月自然贮存和100次高低温循环过程中的变化，阐明胶黏剂的老化机理。结果 光固化胶黏剂的光交联反应在20min后就进行完全，热固化胶黏剂在60℃固化4h后即达到了较高程度的交联，120℃固化对交联程度的影响不大，更多的是对交联结构的完善。经过-45～75℃下100次高低温循环后，胶黏剂的交联结构变化不明显。自然贮存6个月后，胶黏剂不仅发生继续交联，而且结构发生了一定的松弛，这些将对其长期使用稳定性带来影响。结论 低场核磁共振对氢原子的运动能力敏感，而且制样简单，测试速度快，是研究交联结构变化的强有力的工具，对胶黏剂的研制、固化工艺优化、固化机理研究具有重要的应用价值。更多还原

【Abstract】 The work aims to study the curing degree of adhesive and its changes in natural storage and temperature cycle.With the help of the low-field nuclear magnetic resonance （LF-NMR） technology,the change of transverse relaxation time T₂ of hydrogen atom in the adhesive during curing and aging was measured to reflect the development of cross-linked structure during curing and the change of the cross-linked structure during 6 months of natural storage and 100 high and low temperature cycles,and clarify the aging mechanism of the adhesive.The results showed that the photo-cross-linking reaction of the light-cured adhesive was completed in 20 min minutes.The thermosetting adhesive reached a high degree of cross-linking after curing at 60℃ for 4 h.Curing at 120℃ had little effect on the cross-linking degree,but improved the cross-linked structure further.After 100 high and low temperature cycles at -45～75℃,the cross-linked structure of the adhesive did not change obviously.However,after natural storage for 6 months,the adhesive not only continued to cross-link,but also had a certain relaxation in structure,which would affect its long-term use stability.Low-field nuclear magnetic resonance is sensitive to the mobility of hydrogen atoms,simple in preparation and fast in testing.It is a powerful tool to study the changes of the cross-linked structure,and has important application value in the development of adhesives,the optimization of curing process and the study of curing mechanism.更多还原