每年出版 6 期
ISSN 打印: 1543-1649
ISSN 在线: 1940-4352
Indexed in
Quantum Mechanical Simulations and Experimental Evaluations of the Catalysis Reaction of the Reactions of Epoxy Resins with 1-Imidazole and 1-Dimethylbenzylamine
摘要
In this article, the rate of epoxy curing with two different accelerators, i.e., 1-imidazole (MI) and 1-dimethylbenzylamine (DMBA), is experimentally investigated. It has been found that the rate of MI-cured epoxy is higher than that of its DMBA-cured counterpart. Moreover, it has been observed that the Tg of MI-cured epoxy was higher than that of DMBA-cured epoxy. To understand this phenomenon, a quantum mechanical density functional theory code (DMol3) was used to simulate the epoxy reaction using these accelerator molecules to study their effectiveness. This was carried out by analyzing the heights of energy barriers of different polymeric reaction steps and studying the geometry of transition states. From the simulations, it was established that the DMBA epoxy is slower because of its geometric steric hindrance and higher energy of the barrier at the initiation, propagation, and termination steps.
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