pentamethyl diethylenetriamine (pc-5) catalyzed reactions in flame-retardant foams abstract: pentamethyl diethylenetriamine (pc-5) is a tertiary amine catalyst widely employed in the production of polyurethane (pu) foams, particularly those requiring enhanced flame retardancy. this article provides a comprehensive overview of pc-5’s role in the formation and flame-retardant behavior of pu foams. we discuss its chemical properties,...