Abstract: A halogen-free flame retardant obtainable by polycondensation of phosphoric monomers with esterifying monomers is provided. 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.

Abstract: 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.

Abstract: Curing agents for epoxy resins are obtained by A) an addition of at least one aldehyde or ketone to at least one phosphonous acid derivative, followed by B) a condensation reaction of the adduct obtained with at least one diamino or polyamino compound. The resulting curing agents can be used alone or as co-curing agents for epoxy resins, and simultaneously as fire-retardants. Using the curing agents of the invention it is possible to prepare cured epoxy resins modified to be fire retardant which have a phosphorus content of at least 2.2% by weight without lowering the glass transition temperature (Tg) to below 150° C. Use of the curing agents and epoxy resins produceable therewith are other objects of the present invention.