HALOGEN-FREE FLAME RETARDANTS

摘要

The invention relates to a halogen-free flame retardant obtainable by polycondensation of phosphoric monomers with esterifying monomers. The phosphoric monomer is an adduct of 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOPO) and ring-substituted DOPO derivatives to unsaturated carboxylic acids. Monovalent and polyvalent alcohols are used as esterifying monomers. The flame retardant has an average molecular weight of more than 20,000 and an average degree of polymerization Pn of at least 55, and is preferably used for the production of polyamide fibers and polyester fibers by melt spinning.