界面增容剂的结构对PLA/PP共混体系界面状态及性能的影响

通过在聚乳酸(PLA)和聚丙烯(PP)共混体系中分别引入马来酸酐接枝乙烯-辛烯共聚物(POE-g-MAH)和甲基丙烯酸缩水甘油酯接枝乙烯-辛烯共聚物(POE-g-GMA)，制备出具有不同结构及性能的共混材料(PLA/PP/POE-g-MAH，PLA/PP/POE-g-GMA)，并采用转矩流变仪、扫描电子显微镜、差示扫描量热仪、平板流变仪及电子万能试验机等研究了不同界面增容剂的结构对PLA/PP共混体系界面状态及性能的影响。结果表明，POE-g-MAH和POE-g-GMA均可改善PLA与PP的相界面形态，但与POE-g-GMA相比，POE-g-MAH的界面催化效率更高，对PLA/PP共混体系增容效果更好，其可诱导PLA与PP在界面处形成微交联结构，增强PLA与PP的界面相互作用，改善材料的机械性能，当添加4wt%的POE-g-MAH时，PLA/PP/POE-g-MAH共混物的拉伸强度达29.7 MPa，断裂伸长率提升至39.3%，较PLA/PP样品提高了8倍；并且共混材料的冲击强度随着POE-g-MAH含量的增加而增加，当其添加量为6wt%时，材料冲击强度达30.1 kJ/m2，材料具有较好的刚韧平衡性。

The influence of the structure of the interfacial compatibilizer on the interfacial state and performance of the PLA/PP blends

Maleic anhydride grafted ethylene-octene copolymer (POE-g-MAH) and glycidyl methacrylate grafted ethylene-octene copolymer (POE-g-GMA) were introduced into the polylactic acid (PLA)/polypropylene (PP) blends to prepare different structures and performance blended materials (PLA/PP/POE-g-MAH, PLA/PP/POE-g-GMA). The effects of compatibilizers with different structures on the regulation behavior of interface state and performance of PLA/PP blends were investigated by the torque rheometer, DSC, SEM, flat rheometer and electronic universal testing machine, etc. The results showed that both POE-g-MAH and POE-g-GMA could improve the interface morphology of PLA and PP, but compared with POE-g-GMA, the interface catalytic efficiency of POE-g-MAH was higher, which could induce PLA and PP more compatible, and catalyzed the formation of micro cross-linking structure at the interface between PLA and PP, which enhance the interfacial interaction between PLA and PP, and finally improved the mechanical properties of the material. When 4wt% POE-g-MAH was introduced, the tensile strength of the PLA/PP/POE-g-MAH blend reached 29.7 MPa, and the elongation at break increased to 39.3%, which was 8 times higher than that of PLA/PP sample. Also, the impact strength of the samples enhanced with the increase of the content of POE-g-MAH, and when its addition amount was 6wt%, the impact strength of the material reached 30.1 kJ/m2, which had a good balance of rigidity and toughness.