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Direct copolymerization of glycolic acid with lactones in the absence of catalysts

✍ Scribed by Hironobu Fukuzaki; Masaru Yoshida; Masaharu Asano; Yoshikazu Aiba; Minoru Kumakura

Publisher: Elsevier Science
Year: 1990
Tongue: English
Weight: 306 KB
Volume: 26
Category: Article
ISSN: 0014-3057
DOI: 10.1016/0014-3057(90)90052-6

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✦ Synopsis

Glycolic acid (GA) was copolymerized with various lactones such as 7-butyrolactone (BL), 6-valerolactone (VL) and E-caprolactone (CL) in the presence of water without catalysts at 200°C under N2, giving relatively low molecular weight polyesters. This reaction is characterized by direct condensation between linear GA and linear to-hydroxy acids produced by hydrolysis of the cyclic lactones, e.g. 4-hydroxybutyric acid (HBA) for the cyclic BL, 5-hydroxyvaleric acid (HVA) for the cyclic VL, and 6-hydroxycaproic acid (HCA) for the cyclic CL. ~H-NMR spectroscopy showed that GA reacts quantitatively with HVA and HCA, in contrast to low reactivity for HBA.

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