中文摘要：

在超声作用下利用异丙基十二烷基磺酰钛酸酯改性Al2O3纳米粒子，然后把改性纳米Al2O3粒子及LLDPE颗粒引入密炼机中，以熔融共混方法制备LLDPE／纳米Al2O3复合材料。采用FESEM对复合材料中纳米粒子的分散形态进行表征，结果表明，当纳米Al2O3粒子含量为3％时，绝大多数的纳米粒子以〈100nm的尺寸均匀分散在基体中；采用FTIR对纳米复合材料的结构进行表征，结果表明，纳米Al2O3与LLDPE之间形成了化学键合结构；力学分析表明，纳米复合材料的拉伸强度及断裂伸长率均有所增加；采用SEM观察拉伸断裂面的形貌，结果表明，适量的纳米Al2O3粒子可以增强、增韧聚合物基体，而基体和纳米粒子的相容性差时，会逐渐引入缺陷。

英文摘要：

The organic Al2O3 nanoparticles was prepared by means of ultrasonic wave in isopropyl dodecyl sulfonyl titanate as the coupling agent. The LLDPE/Al2O3 nanocomposites was prepared by means of melt-blending. The dispersion morphology of nanocomposites was characterized by FESEM. FESEM reults indicate when the quantity of Al2O3 was 3% ,the most nanoparticles with a particle of about 100nm are homogeneously dispersed in the LLDPE matrix. The mechanical properties of the nanocomposites were increased by eompositing of Al2O3 nanoparticles. The structure of nanocomposites was characterized by FTIR. The results demonstrate that Al2O3 nanoparticles link with LLDPE through a chemical bond. The tensile fracture surface morphology of nanocomposites was characterized by SEM. SEM results showed the appropriate amount of Al2O3 nanoparticles can toughening matrix,but will graduallv introduce defects.