PREPARATION OF MODIFIED 2-ETHYLIMIDAZOLE LATENTCURING AGENT FOR EPOXY RESIN

Abstract

Abstract: In order to prepare imidazole latent curing agents, two modified 2-ethylimidazole derivatives were synthesized by the reaction of 2-ethylimidazole (2EI) with N-(4-hydroxyphenyl) maleimide (HPM) and trichlorocyanide, respectively. Their molecular structures were characterized by IR and NMR. The results showed that N-(4-hydroxyphenyl) maleimide (HPM) and cyanuric chloride reacted with 2-ethylimidazole respectively and completely, and the corresponding target products were obtained. The modified imidazole curing agent was mixed with epoxy resin to study the curing properties and latency of the resin system. The results show that compared with EP/2EI system, the exothermic zone of the modified curing system moves to the high temperature region, and the modified curing system has a longer storage period at room temperature. Maleimide group and triazine ring with strong electron absorption effect reduce the nucleophilicity of imidazole ring and inhibit the curing activity of curing agent at room temperature. In addition, the modified curing agent can overcome the energy barrier of curing reaction and restore the rapid curing ability under the heating condition.

Key words: epoxy resin, 2-ethylimidazole, modification, latent curing agent

CLC Number:

TB332

SHEN Zhong-tao, ZHANG Qiao-xin. PREPARATION OF MODIFIED 2-ETHYLIMIDAZOLE LATENTCURING AGENT FOR EPOXY RESIN[J]. Composites Science and Engineering, 2020, 0(2): 117-121.

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