PRODUCTION OF HIGH-MOLECULAR WEIGHT TYPE FLAME RETARDANT

PURPOSE:To readily obtain the subject flame retardant excellent in thermal stability with hardly any coloring, by thermally reacting a halogenated hydroxy compound with a halogenated diglycidyl ether compound in the presence of a catalyst and subjecting the reaction product to specific treatment. CONSTITUTION:(A) A halogenated dihydroxy compound (e.g., tetrabromobisphenol A) is initially reacted with (B) a halogenated diglycidyl ether compound (e.g., diglycidyl ether of tetrabromobisphenol A) in the presence of a catalyst (e.g., lithium hydroxide) in a solvent (e.g., xylene) while being heated. After completing the reaction, the above-mentioned reaction solution is subsequently charged into a large amount of a solvent (e.g., acetone) hardly dissolving the product to deposit the product. The afore-mentioned product is then repeatedly washed with hot water or the solvent hardly dissolving the product and dried to afford the aimed flame retardant having >=10 molecular weight.