Poly(ε-caprolactone)-grafted acetylated anhydroglucose oligomer by ring-opening polymerization -: Synthesis and characterization

A novel acetylated anhydroglucose oligomer (AGU-oligomer), prepared by acid catalyzed transglycosidation of potato starch triacetate and ethylene glycol, was used as a multifunctional coinitiator for the ring-opening polymerization of E-caprolactone (e-CL). The polymers were synthesized using different weight ratios of the starting materials and were characterized by NMR, SEC, and MALLS. The results confirmed the expected P(AGU/CL) polymer structure, namely a 'comb-like' graft-copolymer having the AGU oligomer as backbone with PCL grafts of variable chain lengths (L-CL = 4-21). Thermal and mechanical properties of graft-copolymers with different epsilon-CL block lengths were examined. By changing the graft length, crystallinity was controlled and amorphous polymers were obtained with AGU-oligomer contents higher than 50 wt %. The tensile properties varied with the composition and a copolymer having 40 wt % of AGU-oligomer behaved like soft elastomer, showing high elongation at break. (c) 2006 Wiley Periodicals, Inc.