PROCESS FOR PRODUCING PHOSPHORUS COMPOUND FLAME RETARDANT, PHOSPHORUS COMPOUND FLAME RETARDANT, AND FLAME-RETARDANT POLYESTER

摘要

A phosphorus compound flame retardant which is to be copolymerized in polyester production and does not arouse problems, for example, that it undergoes pyrolysis, flies out of the system, or causes polymer gelation in the polyester-yielding reaction, under the high-temperature reduced-pressure conditions used for the polycondensation for polyester production. The flame-retardant polyester thus produced has a satisfactory color tone. Also provided are: a process for producing the flame retardant; and a flame-retardant polyester produced through copolymerization with the phosphorus compound flame retardant. The process for producing a phosphorus compound flame retardant comprises reacting an organophosphorus compound with an unsaturated carboxylic acid and/or an anhydride thereof in an alkylene glycol, wherein the reaction is conducted in the presence of at least one antioxidant incorporated in a total amount of 0.001 to 10 wt.% based on the organophosphorus compound.