Synthetic routes to flame retardant isocyanurate of rigid polyurethane foams

摘要

Polyurethanes (PUs) are an important class of polymers that are widely used as thermal insulators in many areas. However pure PUs have high combustibility and low thermal stability, which thermal degradation is only 200 °C. Azacyclic isocyanurate compounds have a high thermostable triazinic ring with high nitrogen content, and gives inherently flame retardant of rigid PUs. It degrades at approximate 350 °C as opposed to 200 °C for urethane. In this paper, we summarized the details of isocyanurate synthesis by cyclo- trimerisation and direct introduction.