【作者】 段先健；

【导师】 伍社毛； 张立群；

【作者基本信息】 北京化工大学 ， 材料加工工程， 2001， 硕士

【摘要】 溶胶-凝胶过程是是一种用金属烷氧化物或金属无机盐在较低温度的条件下制备金属氧化物的方法。溶胶-凝胶技术也是一种新颖的制备有机／无机纳米复合材料的非常有效的方法。它可以对有机／无机纳米复合材料的界面特性进行人工设计，也可以控制纳米粒子的粒径和粒径分布。 本文首次利用溶胶-凝胶法在EPDM硫化胶中制备了原位SiO₂／EPDM纳米复合材料。在EPDM中加入一氯乙酸、白炭黑和硅橡胶，有利于溶胶-凝胶反应时原位SiO₂的生成。利用TGA测试了原位SiO₂的含量，发现这三种物质可使原位SiO₂含量可从1.6％提高到4.1％，此时材料的拉伸强度和定伸应力得到明显的提高。用TEM观察了原位SiO₂粒子在EPDM基质中的相态，结果表明，粒子在基质中呈高度均匀的纳米分散。 对TEOS自身的均相和非均相溶胶-凝胶反应进行了研究，同时也对TEOS在EPDM硫化胶中进行的均相和非均相溶胶-凝胶反应进行了考察，结果表明，与TEOS的直接反应不同，在硫化胶中进行溶胶-凝胶反应吋，非均相反应比均相反应的效果要好。 首次发现在EPDM中加入一氯乙酸后，EPDM硫化胶可以产生拉伸结晶。对EPDM的补强机理进行了初步的探讨。研究了硫化胶交联密度、填料类型和填料用量对硫化胶拉伸强度的影响，结果发现，硫化胶的拉伸强度随着交联密度的增大会出现一个峰值，而且出现峰值的位置（硫化时间）远低于正硫化时间(T₉₀)。这种现象不依赖于硫化体系和胶种。实验结果支持了橡胶补强理论中分子滑动模型和范德华模型。更多还原

【Abstract】 The sol-gel process is a method to prepare metal oxide by using alkoxy metal salt or metal inorganic salt. And the sol-gel technique is a novel and effective route to prepare the organic/inorganic nanocomposite. The interaction between polymers and in-situ nanoparticles can be designed, and the particle size and particle size distribution can also be controlled through this method.The in-situ silica/EPDM nanocomposite was prepared for the first time by the sol-gel process. The amount of the in-situ silica can be improved from 1.6% to 4.1% when the chloroactic acid, silica and SiR were separately introduced into in EPDM. The content of in-situ silica was measured by TG. TEM verified that in-situ silica was nanoparticle and dispersed homogenously in the EPDM matrix.The sol-gel reaction of TEOS in homogeneous phase and heterogeneous phase was studied in this paper. Also the sol-gel reaction in EPDM vulcanizte in homogenous phase and heterogeneous phase was investigated. The results showed that the effect of sol-gel reaction in EPDM in heterogeneous phase was better than that of it in homogenous phase.For the first time we found the strrain-induced crystallization in the EPDM when it was add the chloroactic acid. At the same time, the reinforcement mechanism of EPDM was studied in the thesis. The effect of the cross-linking density, kind of fillers and the loading of fillers on the tensile strength of the vulcanizate was studied. It was shown that there wasa peak in the curves of tensile strength versus the cross-linking density. And the curing time when the peaks arise was much shorter than T90. The results of this experiment hold the model of molecular slippage and the Van de Waals model.更多还原