Novel 3D COFs for enhancing the toughness, flame retardancy, dielectric, and thermal management properties of epoxy resin

In this manuscript, a novel 3D COF (P-Si-N-COF) composed of POSS-based and cyclophosphazene-based units was successfully prepared via a one-step method. Due to its unique framework structure and the distribution of organic groups, the EP molecular chain segments are entangled within the framework and interact with it, thereby enhancing the mechanical properties. Additionally, the P-Si-N-COF, which simultaneously contains Si, P, and N elements, significantly improves the fire-retardant properties of EP, with its combined fire-retardant and mechanical properties far exceeding those of other COFs. Furthermore, the presence of the POSS cage and the overall ordered topological structure in the P-Si-N-COF also synchronously enhances its dielectric and thermal management capabilities. This material provides new insights into the application of EP in 5G base stations and electronic packaging fields.