IMPROVEMENTS IN VISCOSITY REDUCTION OF ETHYLENE GLYCOL-TEREPHTHALIC ACID MIXTURE AT HIGH TEMPERATURES.

摘要

We Claim: 1. The method which comprises mixing terephthalic acid and glycol in the molar ratio of glycol to a"-id of from 0.9:1 to less than 2:1 and from about I to about 15% by weight based on the weight of terephthalic acid present of a material selected from the group cansisting of bis hydroxyethyl terephthalate, dimethyl terephthalate, dimethyl isophthalate, sebacic acid, azelaic acid, low molecular weight polymer and mixture thereof, to form a mixture having a reduced rate of increase in viscosity with increase in temperature.