Biobased grafted polyesters prepared by in situ ring-opening polymerization

EVA-g-PLA and EVA-g-PCL copolymers were synthesized by in situ polymerization of ε-caprolactone and lactide, in the presence of molten ethylene vinyl acetate (EVA) copolymer, using titanium phenoxide (Ti(OPh)4) as initiator. The materials prepared in a internal batch mixer were characterized by 1H NMR, SEM, FTIR, rheology, DSC, TGA and SEC and the synthesized copolymers identified through selective extraction. The mechanical performance was characterized by tensile tests and the biodegradability by the biochemical oxygen demand method. The results indicated that approximately 11 wt.% of EVA-g-PCL and 8 wt.% of EVA-g-PLA copolymers were synthesized. Moreover, the increase of the Young modulus was higher for the sample containing EVA-g-PCL. This sample also exhibited the higher biodegradability (36%).