中文摘要：

采用反应挤出工艺制备了PET／LLDPE-g-MA／MDI的共混合金，研究了该体系在力学性能、形貌形态和热性能的变化。结果表明：共混体系的冲击强度随着扩链剂MDI用量的增加而大幅提高，当扩链剂MDI的添加量为1．2份时，PET／LLDPE-g-MAZMDI共混合金的冲击强度达到26．9kJ／m^2，比未加入MDI时增加了144％。从电镜照片分析看出，该体系形态结构随着MDI用量的增加而逐渐形出了交联网络结构。DSC结果表明扩链和交联反应的发生抑制了PET的结晶。

英文摘要：

The reactive blends of PET/LLDPE-g-MA/MDI were prepared by means of reactive extrusion, the mechanical properties, morphological structure and thermal behavior of the blends were studied. The results showed the Charpy impact strength of PET/LLDPE-g-MA/MDI improved markedly with the increase of the content of MDI, when the content of MDI reached 1.2 phr, the impact strength was 26.9 kJ/m^2, 144% higher than that of PET/LLDPE-g-MA. The analysis of the SEM micrographs showed the morphological structure of the blend formed crosslinking network with the increase of MDI content. The results of DSC showed chain extension reaction and crosslinking restricted the crystallization of PET.