✦ LIBER ✦

Synthesis and characterization of novel biodegradable triblock copolymers from L-Lactide, glycolide, and PPG

✍ Scribed by S. M. F. Farnia; J. Mohammadi-Rovshandeh; M. N. Sarbolouki

Publisher: John Wiley and Sons
Year: 1999
Tongue: English
Weight: 122 KB
Volume: 73
Category: Article
ISSN: 0021-8995
DOI: 10.1002/(sici)1097-4628(19990801)73:5<633::aid-app3>3.0.co;2-#

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✦ Synopsis

Copolymers with a PPG center block and two arms of random glycolide/ lactide copolymers have been synthesized and characterized. Compared to random glycolide/lactide copolymers, these new polymers have high toughness and low elastic modulus. 1 H-NMR spectral lines of glycolide CH 2 protons of the copolymers are essentially identical. These materials show no crystallization transition in DSC thermograms and their melting points with respect to PLLA appeared at lower temperatures, indicating the pivotal role of the PPG center block in the copolymer. Degradation in aqueous media (pH ϭ 6.9, 70°C) with stirring, subjected the two end blocks to hydrolytic degradation. The glycolyl ester bond cleavage was faster than for the lactyl ester bond.

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