Biodegradable polymers from 5-hydroxylevulinic acid: 1. Synthesis and degradation of poly(5-hydroxylevulinic acid)
writer：Linbo Wu*, Yan Zhang, Bo-Geng Li
keywords：Poly(5-hydroxylevulinic acid)，Biobased polymer，Biodegradable polymer，Polycondensation，Glass transition temperature
source：期刊
specific source：Journal of Polymers and Environment 16 (1): 68-73, 2008.
Issue time：2008年
As an attempt to synthesize new biodegradable polymers from renewable cellulose resources, melt polycondensation of 5-hydroxylevulinic acid (5-HLA) was reported for the first time. The resulting product, poly(5-hydroxylevulinic acid) (PHLA), was synthesized and characterized with GPC, FTIR, 1H NMR and DSC. The in vitro degradation behaviors in phosphate-buffered saline (PBS) and in deionized water (DW) were also examined. The molecular weight of PHLA is not high (several 1,000s), but it possesses unordinary high glass transition temperature (as high as 120 C). This is very different from existing aliphatic polyesters that usually have Tgs lower than 60 C. The high Tg is attributed to the formation of inter- and/or intramolecular hydrogen bonds due to a characteristic keto–enol tautomerism equilibrium in the polymer structure. PHLA readily degraded hydrolytically in aqueous media.