中文摘要：

本文利用二苯基甲烷二异氰酸酯（MDI）、4,4’-二氨基二苯醚（ODA）分别对纳米Al_2O_3进行表面改性处理,通过机械搅拌分散和超声分散相结合的方法制备了改性前后纳米Al_2O_3/环氧树脂复合材料,并对其性能进行研究。结果表明：当改性的纳米Al_2O_3添加量为3%时,在不损害其热稳定性的前提下,环氧树脂的韧性和强度得到同时提高。

英文摘要：

In this paper,diphenyl methane diisocyanate（MDI） and 4,4 ＇-diamino diphenyl ether（ODA）were used to modify nano-Al_2O_3,and we prepared the composites with raw nano-Al_2O_3 and modified nano-Al_2O_3 through supersonic disperse instrument and mechanical blending.Then,its performance was studied,the results show that：when midified nano-Al_2O_3 content was 3wt%,toughness and strength of the composites are improved at the same time without damaging its thermal stability.