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Materials Research

Print version ISSN 1516-1439On-line version ISSN 1980-5373

Abstract

MIRANDA, Katiusca Wessler et al. Biodegradable Copolymers Obtained by Solution Polymerization. Mat. Res. [online]. 2015, vol.18, suppl.2, pp.200-204.  Epub Oct 23, 2015. ISSN 1516-1439.  https://doi.org/10.1590/1516-1439.365514.

This study aims the synthesis of copolymers of poly (l-lactic acid) and polycaprolactone by ring opening polymerization. The reactions between l-lactide (LLA) and ε-caprolactone (CL) monomers, in 100/0, 95/5, 90/10 and 80/20 LLA/CL mass ratios, were conducted in refluxing toluene, using Stannous octoate as iniciator, methanol as co-iniciator and inert atmosphere (N2). The reaction medium was maintained under stirring at 120 °C for 24 hours. The samples were characterized by carbon-13 and proton nuclear magnetic resonance (C13-NMR and H1-NMR), and gel permeation chromatography (GPC). Monomers were characterized by thermogravimetry (TG). Copolymers were formed only in samples containing 20 wt% ε-caprolactone. NMR spectra of the other samples showed no evidence of CL units. This fact may be associated with the low-temperature volatilization of monomers. The GPC analysis showed that the increase of CL concentration decrease the molecular weight of copolymers.

Keywords : ring opening polymerization; copolymer; poly(l-lactide acid); polycaprolactone.

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