PRODUCTION OF LACTIC ACID-BASED COPOLYMER

• Main Authors: ISHIHARA JIRO, KOSEKI HIDEKAZU
• Format: Patent
• Language: English
• Published: 07.09.1999
• Edition: 6
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

PROBLEM TO BE SOLVED: To obtain the subject copolymer, transparent, colorless, good in color phase and easily controllable for its plasticity by ring-opening copolymerization of a lactide with a cellulosic ester or the like in the presence of a polymerization catalyst and plasticizer. SOLUTION: This copolymer is obtained by ring-opening copolymerization of (A) a lactide (e.g. L-lactide and D-lactide), (B) 100 pts.wt. of a cellulosic ester or ether (e.g. acetyl cellulose and methyl cellulose) in the presence of (C) preferably 0.001 to 0.5 pts.wt. of a polymerization catalyst (e.g. tin octylate) and (D) 10 to 100 pts.wt. of a plasticizer (e.g. dimethyl phthalate, ethyl phthalyl ethyl glycolate). It is preferable that the component A/component B wt. ratio is 99/1 to 70/30. It is also preferable that the ring-opening copolymerization is effected by adding the component C to the mixture of the component A and component B plasticized with the component D, prepared by melting these components at 100 to 180 deg.C.