Study on Flame Retardancy and Adhesive Properties of Hybrid Flame Retardant Composite Filler-Based Polyurethane

Using a mechano-fusion process, this study investigated the synergistic effect between two flame retardant particles by producing core-shell structured composite particles. The polyurethane adhesive containing the composite particles showed significantly improved adhesion (up to 150%) and peak heat rebrase rate (PHRR) decreased by 30% compared to those containing only single particles. In particular, adding composite particles showed better properties than using individual particles, and the adhesive strength increased linearly with increasing additive amount. The flame retardant used in this study is a biobased material that is eco-friendly and made from recycled materials, contributing to resource circularity. The research findings reported here are expected to contribute to the development of new environmentally friendly flame retardant materials based on bioresources in the future.