Method of making heat-resistant polyester with phenylene-bis-oxazoline
AssigneeUnitika Ltd.
InventorsYoshihiro Arai, Takumi Tanaka
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Abstract
This invention is a method of making heat-resistant polyester, the method being characterized by reacting the polyester consisting of aromatic dicarboxylic acid and the glycol component of 2-6 carbons and being in the molten state with 0.1-5 weight percent of molten 2,2'-1,3-phenylene-bis(2-oxazoline) to reduce the amount of end carboxyl group in the polyester to below 15 g equivalents per 10.sup.6 g of the polymer.
Claims2
In a method of making a heat-resistant polyester, said polyester consisting of an aromatic dicarboxylic acid and a glycol component having 2-6 carbon atoms by reducing the amount of carboxyl end groups in the polyester to below 15 g equivalents per 10.sup.6 g of polymer, the improvement comprising
- reacting said polyester in a molten state with from about 0.1 to about 5 weight percent of molten 2,2'-1,3-phenylene-bis(2-oxazoline), said molten polyester having and intrinsic viscosity of at least 0.50, and
- immediately forming said molten polyester into a shaped article, thereby eliminating decomposition due to remelting.
Dependencies are inferred from the claim text.