PROCESS FOR PRODUCING B-BUTYROLACTONE HOMOPOLYMER OR COPOLYMER
申请人:——
公开号:US20020052458A1
公开(公告)日:2002-05-02
The object of the invention is to provides a process in which a high-molecular-weight &bgr;-butyrolactone homopolymer or copolymer being biodegradable, absorbable into the living body, useful as a functional polymeric material and superior in physical characteristics is produced with high yield and good productivity. This object is solved by a process for producing the homopolymer or copolymer of the invention, which comprises ring-opening polymerization of sole &bgr;-butyrolactone subjected previously to acid removal and dehydration treatment, or of said &bgr;-butyrolactone with other lactones, in the presence of a tin compound represented by the following formula (1) and/or formula (2):
1
wherein R
1
and R
2
and R
4
to R
7
independently represent an alkyl group containing 1 to 12 carbon atoms which may have a branched chain, or a cycloalkyl group containing 5 to 7 carbon atoms, or a phenyl or naphthyl group which may have a substituent group, R
3
represents an alkylene group containing 2 to 12 carbon atoms which may have a substituent group, a cyclopentane-1,2-ylene group or a cyclohexane-1,2-ylene group, and n is an integer of 1 to 10.
A Readily Synthesized and Highly Active Epoxide Carbonylation Catalyst Based on a Chromium Porphyrin Framework: Expanding the Range of Available β-Lactones
作者:Joseph A. R. Schmidt、Viswanath Mahadevan、Yutan D. Y. L. Getzler、Geoffrey W. Coates
DOI:10.1021/ol036244g
日期:2004.2.1
Catalytic carbonylation of epoxides to beta-lactones was effected by a highly active and selective bimetallic catalyst comprised of a chromium(III) porphyrin cation and a cobalt tetracarbonyl anion. The complex is readily synthesized from commercially available compounds in high yield. Carbonylation of numerous linear epoxides, as well as bicyclic epoxides derived from 8- and 12-membered hydrocarbons, proceeded with high activity, selectivity, and yield.
HUFFER, MANFRED;SCHREIER, PETER, FRESENIUS Z. ANAL. CHEM., 333,(1989) N, C. 736-737
作者:HUFFER, MANFRED、SCHREIER, PETER
DOI:——
日期:——
STARCH ESTER BLENDS WITH LINEAR POLYESTERS
申请人:National Starch and Chemical Investment Holding Corporation