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International Journal for Multiscale Computational Engineering
Facteur d'impact: 1.016 Facteur d'impact sur 5 ans: 1.194 SJR: 0.554 SNIP: 0.82 CiteScore™: 2

ISSN Imprimer: 1543-1649
ISSN En ligne: 1940-4352

International Journal for Multiscale Computational Engineering

DOI: 10.1615/IntJMultCompEng.v7.i5.30
pages 409-417

Quantum Mechanical Simulations and Experimental Evaluations of the Catalysis Reaction of the Reactions of Epoxy Resins with 1-Imidazole and 1-Dimethylbenzylamine

B. Singh
ABB Switzerland Ltd. Corporate Research, Baden-Dattwil CH-5405, Switzerland
O. Fritz
ABB Switzerland Ltd. Corporate Research, Baden-Dattwil CH-5405, Switzerland
A. Simperler
Accelrys Ltd., Cambridge CB1 0WN, U.K.
C. Menke
Accelrys GmbH, D-85598 Baldham, Germany

RÉSUMÉ

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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