115. (Sci. China Chem.) Dynamic cross-linked latent accelerators based on hindered urea bond for one-component epoxy resins
writer：Xin Wang, Falin Li, Changhui Jing, Shuaiqi Yang, Shuai Du, Fengyuan Zhang and Songqi Ma*
keywords：epoxy resin, latent accelerator, dynamic covalent bond, high performance, dissociation
source：期刊
specific source：Science China Chemistry
Issue time：2025年
Dynamic cross-linking chemistry was employed to synthesize latent accelerators, enabling both prolonged storage stability and enhanced curing performance of one-component epoxy resins. One-component epoxy resins, like epoxy/dicyandiamide system, have gained increasing demand in various applications by virtue of their simple process and stable quality; however, they often require high curing temperatures and limited room-temperature storage life. Herein, a novel class of dynamically cross-linked latent accelerators (HUBs) based on hindered urea bond were designed and synthesized through free radical copolymerization of 1-vinylimidazole and 2-(tert-butylamino) ethyl methacrylate, followed by cross-linking with isophorone diisocyanate. Upon incorporation into the epoxy/dicyandiamide system, HUBs significantly lowered the curing temperature while maintaining excellent room-temperature storage stability for over 129 days, surpassing traditional imidazole-based accelerators. Moreover, the cured epoxy resins exhibited superior thermal properties, with increased glass transition temperatures reaching up to 156 °C, along with enhanced moduli and solvent resistance. This innovative strategy utilizing dynamic covalent bonds offers a promising approach for developing environmentally friendly, high-performance epoxy materials, holding significant potential in applications such as composites, high-performance coatings, electronic packaging materials, and structural adhesives.
全文鏈接：https://doi.org/10.1007/s11426-025-2842-9