Accelerated Degradation of Poly(e-caprolactone) by Organic Amines
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Authors
Lin, W.-J.
Flanagan, D.R.
Linhardt, Robert J.
Issue Date
1994
Type
Article
Language
ENG
Keywords
Biology , Chemistry and chemical biology , Chemical and biological engineering , Biomedical engineering
Alternative Title
Abstract
The solid-state degradation of poly(epsilon-caprolactone) catalyzed by primary, secondary and tertiary alkylamines was investigated. The degradation process was monitored by weight loss and molecular weight change measured by gel permeation chromatography. Degradation studies were conducted at 37 degrees C in methanol solutions of the alkylamines. Primary alkylamines caused rapid weight loss (i.e., approximately 90% weight loss in 30 days) that depended on alkylamine concentration, molar ratio of alkylamine to poly(epsilon-caprolactone) monomer and alkyl chain length. The secondary alkylamines caused less rapid polymer weight loss (i.e., approximately 90%) weight loss within 80 days). One tertiary alkylamine (N,N-diisopropylethylamine) showed little catalytic effect while a bicyclic tertiary alkylamine (quinuclidine) was about as catalytic as the primary alkylamines. The degradation products isolated when primary alkylamines were used include both esters and amides indicating that nucleophilic attack by the alkylamines competed with the amine-catalyzed methanolysis reaction. Only ester moieties could be identified in the products from reactions containing secondary and tertiary alkylamines, which indicated that they acted as nucleophilic catalysts. All of the primary alkylamines reduced poly(epsilon-caprolactone) molecular weight from about 25,000 to 10,000 within 10 days after which the molecular weight of the remaining solid leveled off even though weight loss continued.
Description
Pharmaceutical Research, 11, 1030-1034
Note : if this item contains full text it may be a preprint, author manuscript, or a Gold OA copy that permits redistribution with a license such as CC BY. The final version is available through the publisher’s platform.
Note : if this item contains full text it may be a preprint, author manuscript, or a Gold OA copy that permits redistribution with a license such as CC BY. The final version is available through the publisher’s platform.
Full Citation
Accelerated Degradation of Poly(e-caprolactone) by Organic Amines, W.-J. Lin, D.R. Flanagan, R.J. Linhardt, Pharmaceutical Research, 11, 1030-1034, 1994.