In vitro enzymatic degradation of nonporous films of segmented poly(ether urethane) (Pellethane 2363-80AE) was investigated by incubating the biomaterial in concentrated trypsin solutions for 5 months at room temperature. Chemical degradation of films was monitored by surface analysis techniques suc
Degradation kinetics of poly(ether-urethane) Estane® induced by electron irradiation
✍ Scribed by A. Dannoux; S. Esnouf; J. Begue; B. Amekraz; C. Moulin
- Publisher
- Elsevier Science
- Year
- 2005
- Tongue
- English
- Weight
- 179 KB
- Volume
- 236
- Category
- Article
- ISSN
- 0168-583X
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✦ Synopsis
Radiation effects on a segmented aromatic poly(ether-urethane) induced by electron beam irradiation under oxygen atmosphere were investigated using Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR) in order to determine the degradation mechanisms. Thin films have been irradiated under a dose rate of 1 MGy/h with absorbed doses varying from 25 to 1000 kGy under O 2 . FTIR spectra have shown the formation of hydroperoxides, carboxylic acids, primary amines, alcohols, esters and formates. Moreover, the decrease of urethane and ether absorbances revealed the degradation of both soft and hard segments. Spin-trapping technique was used to monitor the evolution of short-lived peroxy and alkyl radicals at room temperature. Finally, a mechanism of degradation for electron irradiated polyurethane is proposed.
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