Patent ID: 11708453

Abstract:
Process for preparing copolyesters by introducing TPA, EG, and CHDM at an EG:TPA molar ratio of 2.3:1 to 2.7:1 into a reaction zone; reacting TPA with EG and CHDM at a temperature of at least 250° C. and pressure of up to 40 psi to form a first esterification product; passing the first esterification product to a reaction zone; esterifying the first esterification product at a temperature of at least 250° C. and pressure of up to 20 psi to form a second esterification product, passing the second esterification product to a reaction zone; polycondensing the second esterification product in the presence of a catalyst to form a prepolymerization product; passing the prepolymerization product to one or more reaction zones; and polycondensing the prepolymerization product in the presence of the catalyst to form a copolyester comprising 1.0 wt % or less of DEG, without requiring the use of DEG-suppressing additives.