Abstract: The invention relates to a process of preparing glycol carboxyethylmethylphosphinate, which comprises a) reacting elemental yellow phosphorus with methyl chloride in the presence of an alkali or alkaline earth metal hydroxide to form a mixture which includes the alkali and/or alkaline earth metal salts of methylphosphonous, phosphorous and hypophosphorous acids as main constituents, b) esterifying the methylphosphonous acid from the mixture obtained by a), c) removing the methylphosphonous ester from the mixture, d) adding the thus obtained methylphosphonous ester to an acrylic ester, e) hydrolyzing the diester thus obtained, f) esterifying the resulting carboxyethylmethylphosphinic acid with ethylene glycol directly to the glycol carboxyethylmethylphosphinate. The invention also relates to the use of the glycol carboxyethylmethylphosphinates prepared according to the invention as reactive flame retardants for polymers.

Abstract: The invention relates to a process of preparing glycol carboxyethylmethylphosphinate, which comprises

Abstract: The present invention relates to a process for the preparation of phosphinic acid esters, which comprises a) reacting elemental yellow phosphorus with alkylating agents in the presence of a base to give a mixture which comprises, as principal constituents, the (metal) salts of alkylphosphonous, phosphorous and hypophosphorous acids, b) esterifying the principal constituents of the mixture from a) to give an ester mixture, c) isolating the ester of the alkylphosphonous acid from the ester mixture, d) adding the resultant ester of the alkylphosphonous acid onto an olefin containing a functional group. The invention likewise relates to the use of the phosphinic acid esters prepared by this process, inter alia as flame retardants and precursors for further syntheses.

Abstract: The present invention relates to a process for preparing phosphinic esters which comprisesa) reacting elemental yellow phosphorus with alkyl halides in the presence of alkali metal hydroxide or alkaline earth metal hydroxide to form a mixture which comprises as main constituents the alkali metal salts and/or alkaline earth metal salts of alkylphosphonous acid, phosphorous acid and hypophosphorous acidb) removing the alkylphosphonous acid from the mixture obtained as described in a),c) esterifying the alkylphosphonous acid,d) adding the resultant ester of the alkylphosphonous acid to a compound having at least one C.dbd.C double bond.The invention likewise relates to the use of the phosphinic esters prepared by this process inter alia as flame retardants and as precursor for further syntheses.

Abstract: The present invention relates to a process for preparing phosphonous esters which comprisesa) reacting elemental yellow phosphorus with alkyl halides in the presence of alkali metal hydroxides and/or alkaline earth metal hydroxides to form a mixture which comprises, as main components, the alkali metal salts and/or alkaline earth metal salts of the alkylphosphonous, phosphorous and hypophosphorous acids,b) removing the alkylphosphonous acid from the mixture obtained by a)c) esterifying the alkylphosphonous acid.The invention likewise relates to the use of the phosphonous esters prepared by this process.