Polyester resin, molded object thereof, and processes for producing these
AssigneeAsahi Kasei Chemicals Corporation
InventorsHiroshi Yokoyama, Hiroshige Okamoto, Muneaki Aminaka
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Abstract
A polyethylene terephthalate resin which is obtained by melt polymerization at a reduced pressure or in an inert gas atmosphere and has the following properties (A) to (F): (A) the intrinsic viscosity [η] is 0.4-2.5 Dl/g; (B) the content of carboxy groups present at polymer ends is 30 meq/kg or lower; (C) the acetaldehyde content is 10 ppm or lower; (D) a hexafluoroisopropanol solution of the resin, when analyzed by the transmission method, has a hue which has an L value of 99 or larger and a b value of 0.4 or smaller; (E) the Mw/Mn is 1.8-2.3; and (F) the cyclic trimer content is 5 wt. % or lower.
Claims9
A polyethylene terephthalate resin obtained by melt polymerization under a reduced pressure or under an inert gas atmosphere and having the properties comprising:
- (A) an intrinsic viscosity [η] of 0.4 to 2.5 dl/g;
- (B) a content of carboxyl end groups of 30 meq/kg or less;
- (C) a content of acetaldehyde of 10 ppm or less;
- (D) a hue represented by the L value of 99 or greater and the b value of 0.4 or less,
- said hue being measured by transmission of hexafluoroisopropanol solution;
- (E) Mw/Mn of 1.8 to 2.3;
- and
- (F) a content of cyclic trimer of 5 wt % or less.
Dependencies are inferred from the claim text.