Synthesis of polyphosphorinanes Part II. Preparation, characterization and thermal properties of novel flame retardants

Abstract

We report here the investigation of new flame retardant compounds for textiles, obtained by radical polymerization of allyloxydioxaphosphorinanes. These monomers were first synthesized by a transesterification reaction. A deep NMR study of such compounds revealed the existence of diastereoisomers Z and E. Radical polymerizations of allyloxydioxaphosphorinanes in the presence of a chain transfer agent, i.e.dimethylhydrogenophosphonate, led to oligomers of rather low molecular weights and especially adducts with DP 1 and 2. It was demonstrated that radical polymerization of allyloxydioxaphosphorinanes with P–R (R being alkyl or aryl) does afford only linear oligomers instead of hyperbranched polymers when R is hydrogen. The thermogravimetric analyses of the oligomers showed a good thermal stability and a high content of char residue (more than 16 wt%). The flame retardant properties were also evaluated by microcalorimeter tests and revealed an efficient behavior especially in the condensed phase, comparatively to Antiblaze 19®, the flame retardant commercial product for polyester textile.