Abstract: Polyamide elastomer(polyamide-polyoxyethylene copolymer, PAE) was used to toughen PLA via melt blending. It was found that a brittle-ductile transition occurred when PAE content was between 20 %～30 %. The maximum impact strength was 67.6 J/m, but the tensile strength and modulus decreased sharply. When the PAE contents were between 5 %～10 %, the blend exhibited the maximal comprehensive strength and toughness with the elongation at break increased by 40 times. SEM micropgraphs showed the blend was phase separated, but the DSC data showed that Tg and Tm changed as PAE content was changed. TG data showed that the degradation temperature of PLA increased with increasing PAE content. All the behavior indicated that the blend was partial miscibility for somewhat specific interaction between the two phases.

Key words: polyamide elastomer, toughening, melt blending, poly(lactic acid)