Synthesis of biobased and biodegradable polymers from renewable biomass has attracted much attention in recent years.Levulinic acid has been deemed as a platform chemical from non-food stuff biomass

and some of its derivatives are starting materials for new polymers.In this paper

poly(5-hydroxylevulinic acid-co-L-lactic acid) (PHLL) was synthesized via melt copolycondensation of 5-hydroxylevulinic acid (5-HLA) and L-lactic acid (LLA) and characterized with GPC

X-ray

1H-NMR

FTIR and DSC.The results showed that the copolymers had interesting olefinic ether branch structures formed via etherification between carbonyl of 5-HLA and hydroxyl in LLA.The copolymer was amorphous in a broad composition range and had high glass transition temperature (Tg) ranging from 54.6℃ to 91.4℃

which increased with the increase of 5-HLA content due to the existence of hydrogen bonds in the 5-HLA moiety of the copolymer.The hydrolytic degradation behavior in deionized water showed that PHLL readily degraded hydrolytically in aqueous medium

and the degradation rate depended on its microstructure.The amorphous LLA moiety degraded faster than the 5HLA counterpart.