XPS analysis of char residue from an intumescent flame retardant rigid PU composite foam

Abstract

A flame retarded rigid PU foam was prepared using polyols and diisocyanates with a modified intumescent flame retardant (MIFR) via polyoxyethylene nonylphenol ether (surfactant TX-10). The MIFR included a new carbon source, calcium 3-hydroxy-2, 2-bis(hydroxymethyl) propyl phosphate. The carbon residue from the flame retardant rigid PU foams after UL-94 test was investigated with XPS. The data showed that the addition of MIFR into PU foams could promote formation of pure carbon char and P-C bond.