SYNTHESIS OF POLYGLYCOLIC ACID WITH HIGH MOLECULAR WEIGHT AND HIGH SOLUBILITY AT LOW COST

摘要

The invention relates to the synthesis method of polyglycolic acid (PGA) obtained by removing the excessive water and monomer formed subsequent to condensation by means of an organic solvent and using azeotropic distillation method in the presence of a catalyst. The invention is a synthesis method of polyglycolic acid with high molecular weight and high solubility, characterized by comprising the steps of placing the glycolic acid in reaction medium with a catalyst; using hydrophilic organic solvents for removing the excessive water and monomer formed during condensation; mixing and boiling the mixture; stabilizing the amount of solvent in reaction medium and distilling the water off by means of Dean stark apparatus and/or a similar apparatus; refluxing the solid polymer obtained at the end of the reaction with ethyl acetate and removing the same from monomer residue and catalyst.