Patent ID: 6420511
Filing Date: 2002-07-16
Classification: C08G

Abstract:
A process for the preparation of aromatic polyesters comprising(a) polymerizing (i) an aromatic dicarboxylic acid substituted with a polar group and (ii) an alkali metal salt of a tetra-substituted aromatic diol in a reaction mixture in the presence of a solvent consisting essentially of an organic solvent at a temperature in the range of âˆ’5 to 80Â° C. for a period of 1to 36 hours with stirring of the reaction mixture, said reaction mixture comprising the dicarboxylic acid in an amount of 20-75 weight percent, the alkali metal salt of a tetra-substituted aromatic diol in an amount of 25 to 78 weight percent and the solvent in an amount of 2 to20 weight percent; (b) adding the reaction mixture to a nonsolvent to cause precipitation of a polymer; (c) separating and purifying the precipitated polymer; and (d) drying the polymer at a temperature in a range of 40-80Â° C. for 24 to 48 hours.