Title:
PRODUCTION OF LACTIC ACID COPOLYESTER AND PACKAGING MATERIAL
Document Type and Number:
Japanese Patent JP3307748
Kind Code:
B2
Abstract:
PURPOSE: To obtain a degradable linear lactic acid copolyester having a high molecular weight and excellent toughness, rigidity, flexibility and transparency by reacting a lactide with a polyester polymer in the presence of a ring-opening polymerization catalyst.
CONSTITUTION: 25-98 pts.wt. lactide (A), 1-70 pts.wt. linear aromatic polyester (B) comprising an aromatic dicarboxylic acid component and an aliphatic diol component and having a weight-average molecular weight of 10000-250000, and 1-70 pts.wt. linear aliphatic polyester (C) comprising an aliphatic dicarboxylic acid component and an aliphatic diol component and having a weight-average molecular weight of 10000-250000 are subjected to ring-opening polymerization and transesterification in the presence of a ring-opening polymerization catalyst (D). The weight-average molecular weight of the obtained polyester is 20000-400000. This polyester is obtained also by the combination of component A with component B or of component A with component C or by the combination of component A with a linear aromatic/aliphatic polyester (E) comprising an aliphatic dicarboxylic acid and an aliphatic diol.
Inventors:
Hiroshi Ebato
Yasutoshi Kakizawa
Kousuke Arai
Akira Ohya
Hideyuki Furuta
Yasutoshi Kakizawa
Kousuke Arai
Akira Ohya
Hideyuki Furuta
Application Number:
JP32706893A
Publication Date:
July 24, 2002
Filing Date:
December 24, 1993
Export Citation:
Assignee:
Dainippon Ink and Chemicals Co., Ltd.
International Classes:
C08G63/08; C08G63/60; C08G63/78; C08L67/00; C08L67/02; C08L67/04; (IPC1-7): C08G63/78
Domestic Patent References:
| JP60252622A |
Attorney, Agent or Firm:
Victory Takahashi