Enzymatic Synthesis of Chitin‐ and Chitosan‐graft‐Aliphatic Polyesters

Summary: The title polymers, in which both the stem and the graft are biodegradable, have been synthesized for the first time in a one‐pot, lipase‐catalyzed, graft‐polymerization reaction (in bulk, at 70 °C) of β ‐butyrolactone ( β ‐BL) and ε ‐caprolactone ( ε ‐CL) onto chitin and chitosan. The reactivity order of the lactones was found to be ε ‐CL > β ‐BL ≫ γ ‐BL (no reaction). All the graft polymers prepared are insoluble in common organic solvents. Synthesis of chitin‐ or chitosan‐ graft ‐aliphatic polyesters. image Synthesis of chitin‐ or chitosan‐ graft ‐aliphatic polyesters.