abstract |
Using an alkanolamine titanium chelate catalyst, such as triethanolamine titanium chelate, in small catalytic amounts to esterify and polycondense aromatic polycarboxylic acids or anhydrides, such as terephthalic acid, with a glycol, such as ethylene glycol at low glycol to acid reactant ratios surprisingly yields a polyester of low diethylene glycol content without adding an additional diethylene glycol suppressant. |