Benzimidazole derivatives and their complexes as accelerators for curing of epoxy resin

Abstract

Bisphenol-A-based epoxy resin was cured with an anhydride hardener in the presence of benzimidazoles and their complexes as accelerators. Investigations have revealed an appreciable reduction in the cure and gel times. The kinetic studies based on DSC showed that the rate of curing increases with enhanced concentration of accelerators. The coefficient of thermal expansion has been reduced considerably in the presence of the benzimidazole. The electrical properties of the cured epoxy resin system were unaffected by lower concentrations of benzimidazoles. A mechanism for curing has been proposed with 1,3-bis(2-benzimidazolyl)benzene as accelerator based on IR studies, which indicate the involvement of the secondary and tertiary nitrogen of the benzimidazole in the crosslinking of the resin system.

Curing behavior and rheology properties of alkyl‐imidazolium‐treated rectorite/epoxy nanocomposites

“…From the following results, we suppose that both the curing agent (TOA) and clay filler can enhance the curing behavior. Here, we propose that two curing reactions may happen in the EP/TOA/OREC system, including imidazole curing reaction [] and TOA curing reaction []. The possible scheme of the curing reaction is shown in Fig.…”

Release Behavior of Benzimidazole-Intercalated α-Zirconium Phosphate as a Latent Thermal Initiator in the Reaction of Epoxy Resin

“…Benzimidazoles are known as good curing agents for epoxy-anhydride systems [16]. Using benzimidazole as an intercalation compound, Costantino et al [17] reported a molar ratio of benzimidazole/zirconium phosphate of up to 1.9.…”

Synthesis of substituted 2-vinyl and 2-phenylbenzimidazoles and progress towards the synthesis of natural products ht-13-A and ht-13-B

“…A small sampling of the published results of substituted 2phenylbenzimidazoles for biological activity includes antibacterial activity against methicillin resistant Staphylococcus aureus 35 , AMP-activated protein kinase activators to fight obesity 36 , as topoisomerase I poisons 37 , disrupting of Golgi processing and potent activity against IgE 38 , as a novel peptide coupling reagent 39 , for antitumor activity 40 , for antimicrobial and antifungal activity 41 , for antioxidant properties 42 , and as inhibitors of HIV-1 reverse transcriptase 43 . A few of the other possible uses of substituted 2phenylbenzimidazoles include their use in the indirect fluorescent determination of pharmaceutical compounds 44 , as accelerators for curing of epoxy resin 45 , in a complex with iridium to form an organic light emitting diode 46 , as an additive in electrolytic solution to effect dye-sensitized solar cell performance 47 , and as intermediates in organic reactions forming triazines 48 , diketones 49 , or benzotriazoles 50 . A variety of the above discussed substituted 2-phenylbenzimidazoles can be seen in Figure 6.…”