Preparation and performance study of latent imidazole curing agents for epoxy resin

doi:10.19936/j.cnki.2096-8000.20260428.009

Abstract

Abstract: Imidazole barbiturate (BAM) was synthesized through an acid-base neutralization reaction between imidazole (MI) and barbituric acid (BA) in an aqueous solution and employed as a latent curing agent for epoxy resin (EP) systems. This study systematically characterized the molecular structure of BAM using Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy.The latent curing behavior, storage stability, and mechanical performance of the EP/BAM system were evaluated using differential scanning calorimetry, rheological analysis, dynamic mechanical analysis, and mechanical property testing. The results showed that the introduction of barbituric acid significantly reduced the curing activity of imidazole, shifting the curing exothermic peak of the EP/BAM system approximately 60 ℃ higher compared to the EP/MI system. The EP/BAM system exhibited excellent storage stability with a room-temperature storage period of up to 63 days, while achieving rapid curing under moderate-temperature conditions. Additionally, the cured EP/BAM system maintained a glass transition temperature of 163.9 ℃ and showed higher strength and modulus compared to the EP/MI system, demonstrating superior thermal resistance and mechanical performance. In conclusion, the EP/BAM system exhibits remarkable advantages in latency, storage stability, and post-curing performance, providing a novel and efficient strategy for the development of one-component epoxy resin systems.

Key words: one-component epoxy resin, latent curing agent, imidazole, thermal resistance, mechanical performance

CLC Number:

TB332

LIU Wei. Preparation and performance study of latent imidazole curing agents for epoxy resin[J]. COMPOSITES SCIENCE AND ENGINEERING, 2026, 0(4): 72-77.

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