A NEW PREPARING METHOD OF METHOXYPOLYETHYLENEGLYCOL AND ITS DERIVATIVES

摘要

A method for preparing methoxypolyethylene glycol(m-PEG) phthalate is provided to obtain high-purity m-PEG derivatives present stably in an aqueous solution state, and to avoid a need for an organic solvent. The method for preparing methoxypolyethylene glycol phthalate with a purity of at least 99% comprises the steps of: (1) introducing methoxypolyethylene glycol into toluene and removing toluene by atmospheric distillation; (2) cooling the product to room temperature and introducing a metal alkoxide in the presence of an alcohol; (3) introducing phthalic anhydride thereto to perform a reaction; (4) neutralizing the reaction mixture and extracting the reaction mixture with methylene chloride; (5) washing the methylene chloride layer with water; (6) introducing a solvent to the methylene chloride layer to perform crystallization; and (7) forming an aqueous solution of the crystallized product and purifying the aqueous solution by column chromatography.