Crosslinked phenoxyphosphazene compound, process for producing the same, flame retardant, flame retardant resin composition, and flame retardant resin molded article

摘要

A flame retardant which has advantages, for example, that it is halogen-free, has a high melting oint, is lowly volatile, and does not impair the properties inherent in resins. The flame retardant comprises a cross-linked phenoxyphosphazene compound which is a compound obtained by cross-linking a pkosphazene compound with cross-linking groups, e.g., phenylene groups, each cross-linking group being interposed between two oxygen atoms left by phenyl group elimination, and which has no free hydroxyl group (derived from the cross-linking group) in the molecule and contains phenyl groups in an amount of 50 to 99.9% based on the total number of all the phenyl groups in the phosphazene compound.