超微细Al_2O_3与PMMA溶液复合技术的研究

Poly(Methyl Methacrylate) Toughened and Strengened by Ultrafine Al 2O 3 Particles

利用溶液复合技术制备了超微细Ａｌ２Ｏ３粒子与聚甲基丙烯酸甲酯（ＰＭＭＡ）的复合材料。ＳＥＭ证示采用乙酸乙酯作溶剂，可以将超微细Ａｌ２Ｏ３很好地分散于ＰＭＭＡ基体中，力学性能测试结果表明超微细Ａｌ２Ｏ３对ＰＭ－ＭＡ具有很好的增韧增强作用，当Ａｌ２Ｏ３用量为１０％，粒子半径为０．０５μｍ时，ＰＭＭＡ的拉伸强度增加３倍，缺口冲击强度增加了１０倍。差热分析结果说明超微细Ａｌ２Ｏ３加入ＰＭＭＡ后，提高了ＰＭＭＡ的热分解温度，降低了Ａｌ２Ｏ３的相转变温度，预示超微细Ａｌ２Ｏ３与ＰＭＭＡ可能发生了化学结合。

In this papers,the poly(methyl methacrylate)/Al 2O 3 (PMMA/Al 2O 3) composite was prepared in the solution of ethyl acetate. The effects of Al 2O 3 particles contents and size on tensile strength and notched izod impact strength of PMMA were investigated. The results show that the Al 2O 3 particle which radius is below 1.0 μm could toughen and strengen PMMA, the particle which radius is above 10 μm couldn’t.It is interesting to find that the critical matrix ligament thickness L c is 0.08 μm,when L>L c ,PMMA is not tougnened,when L<L c ,PMMA is toughened. The SEM of PMMA/Al 2O 3 sample shows clearly the ultrafine Al 2O 3 particle are dispered in PMMA matrix and don’t aggregate. The DSC cureves indicate that there is chemical bonding between ultrafine Al 2O 3 and PMMA.