The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 1998
Filed:
Mar. 17, 1997
Applicant:
Inventors:
Masaaki Oota, Kyoto, JP;
Masahiro Ito, Kyoto, JP;
Assignee:
Shimadzu Corporation, Kyoto, JP;
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528354 ; 528310 ; 528322 ; 528357 ; 528358 ; 528361 ;
Abstract
The polymerization reaction is conducted by heating a lactide, a cyclic imide compound (e.g. succinimide, etc.) and a polymerization catalyst (e.g. tin octylate, etc.) at 100-190.degree. C. with stirring under a nitrogen gas flow. It is preferred that an amount of the cyclic imide compound is from 1 to 35% by mole based on the lactide. Even if an amount of the polymerization catalyst is small, e.g. 0.00001-0.1 mole %, based on the lactide, polylactic acid can be efficiently prepared. It is possible to avoid remains of the catalyst in the polymer and coloring of the polymer.