The influence of mesoporous silica modified with phosphorus and nitrogen‐containing hyperbranched molecules on thermal stability, combustion behavior, and toxic volatiles of epoxy resin

Abstract

A hybrid material (HPPA‐SH‐mSiO2) containing multiple flame‐retardant elements was synthesized and characterized using NMR, FTIR, and XPS techniques. This hybrid was synthesized by the “thiol–ene” click reaction of thiol‐functionalized mesoporous silica (SH‐mSiO2) with ene‐terminated hyperbranched polyphosphate acrylate (HPPA).When 2 wt% HPPA‐SH‐mSiO2 hybrid was added to an epoxy matrix, thermogravimetric analysis (TGA) showed that the incorporation of HPPA‐SH‐mSiO2 increased the thermal stability of epoxy resin composites. Moreover, the combustion behavior of epoxy composites was investigated using a cone calorimeter, and the results show that the PHRR and THR of EP/HPPA‐SH‐mSiO2 composites clearly decreased by 28.7% and 16%, respectively. Volatile toxic compounds such as aromatic compounds, CO, carbonyl compounds, and hydrocarbons were identified using TGA‐infrared spectroscopy coupling technique. The effect of HPPA‐SH‐mSiO2 hybrids on the removal of toxic volatiles was also investigated. Functionalized mesoporous silica and polymer composites have potential applications.