In this study,polylactic polyurethane block prepolymer(PLA-b-PUP)was synthesized and used as the active compatibilizer of polylactic acid(PLA)and thermoplastic polyurethane(TPU).PLA/TPU/PLA-b-PUP supertoughened-blends were prepared by in-situ reaction.The mechanical properties,thermal properties and toughening mechanism of the blends were investigated by tensile test,impact test,SEM,FTIR,DSC and TGA.The results showed that the isocyanate groups in the PLA-b-PUP reacted with the active groups on PLA and TPU,which significantly improved the compatibility of the two-phase interface of PLA/TPU blends.With the addition of PLA-b-PUP,the glass transition temperature and relative crystallinity of PLA in the blend gradually decreased.When the mass fraction of PLA-b-PUP was 4%of that of PLA/TPU blend,the elongation at break and notch impact strength of the blend were 8.12 and 2.73 times of those without compatilizer,respectively,showing a good capacity and toughening effect.After addition of PLA-b-PUP,the initial decomposition temperature decreased,but the fastest decomposition temperature increased.
维普
万方数据