Abstract: Biobased poly(ether-block-amide)(PEBA) was used to toughen poly(lactic acid)(PLA) to prepare super-tough PLA composites. In order to improve the compatibility between PEBA and PLA, PEBA-GMA was prepared by graft modification of PEBA by monomer glycidyl methacrylate(GMA), comonomer vinyl pyrrolidone(NVP) and initiator diisopropyl peroxide(DCP). The effect of the adding amounts of grafted monomers on the properties of PLA/PEBA-GMA composites was investigated. The results exhibit that the notched impact strength of the PLA composites increases gradually with the rise of the adding amount of grafted monomers. When the amount of grafted monomers GMA, NVP, DCP were 2.5, 2.5, 0.25 g respectively, the impact strength of the blends was as high as 88.6 kJ/m² and the elongation at break was up to 164.1%. It is explained that the end groups of polylactic acid(-OH and -COOH) reacts with the epoxy groups on PEBA-GMA during melt blending, which improves the interfacial compatibility between the PLA and PEBA-GMA. With the increase of the adding amounts of grafted monomers, the particle size of the dispersed phase PEBA-GMA decreased gradually and dispersed evenly. As a result, super-tough PLA composite was prepared.

Key words: Poly(lactic acid), Poly(ether-block-amide), Graft, Toughenness