Chemical and Biomolecular Engineering Research and Publications
Date of this Version
5-25-1999
Abstract
Biodegradable polymers were formed from N-benzyloxycarbonyl-L-glutamic acid with the comono-mers ethylene glycol, diglycidyl ether of 1,4-butanediol, and diglycidyl ether of bisphenol A. The three polymers were a linear and a rosslinked heterochain polyester and a crosslinked polyester that contained aromatic units within its network chains. The thermoplastic resin and the soluble fractions for the thermo-setting resins were characterized by gel permeation chromatography. Conversions for carboxylic acid were determined by titrations. A quality, 22,000 molecular weight thermoplastic resin was formed. The two ther-mosets were cured past their gel points. Gelation analysis revealed that the relative rate constants for the sequential oxirane/ acid and alcohol/acid reactions were distinct. With diglycidyl ether of 1,4-butanediol, the ratio of the respective rate constants was 3; with diglycidyl ether of bisphenol A, the ratio approached 200. The resins hydrolyzed to monomers in the presence of lipase, but in the presence of a mixed microbial cul-ture, only the first two resins decayed to biomass, respiratory gases, and water. The third resin was inert during the period of observation. amino-protected glutamic acid; biodegradable polymers; gelation; polymer networks; polyesters
Comments
"This article is a preprint of an article published in © Journal of Applied Polymer Sci-ence, Vol. 73, Issue 6, 869–879 (1999). Published Online: 25 May 1999 Copyright © 1999 John Wiley & Sons, Inc.CCC 0021-8995/99/060869-11” This article is available at the publishers site: http://www3.interscience.wiley.com/cgi-bin/abstract/61501069/ABSTRACT