【作者】 刘辉；

【导师】 郝志显；

【作者基本信息】 同济大学 ， 物理化学， 2007， 硕士

【摘要】 微球与介孔材料是当今材料制备中的研究热点，随着纳米材料科学的快速发展，各种新型的纳米材料不断涌现，而纳米材料在工业中的应用也越来越显著。作为纳米材料的重要组成微球与介孔材料的制备也就越来越受到重视。本文采用新的合成方法合成了有机一无机复合微球材料，采用多种模板法制备了各种介孔材料，用扫描电镜(SEM)、傅立叶变换红外光谱(FI-IR)和差热分析(DTA)等方法对所得材料进行了表征。 以甲醛与尿素作为单体在正硅酸乙酯水解所得的氧化硅溶胶中进行聚合反应制得了有机—无机二氧化硅复合微球。实验发现通过改变反应原料比和反应条件可以改变所得微球的精细结构，在尿素和甲醛的摩尔比等于2时制得的微球具有核壳结构的微观特征，在尿素和甲醛的摩尔比等于1时制得的微球具有多孔网络结构的特征，并且在这个条件下减少原料中有机物成分的量会使得微球的精细结构有向核壳结构改变的趋势，根据实验表征结果对各种精细结构不同的微球的合成机理进行推测。 用酸性条件下正硅酸乙酯的水解和尿素、乙二醛聚合反应同时一步原位进行的方法合成了二氧化硅复合粉体和凝胶块体材料。实验发现在尿素和乙二醛的摩尔比小于1时反应体系才会产生白色粉体沉淀，而在尿素和乙二醛的摩尔比大于1时改变反应性单体尿素和乙二醛醛以及正硅酸乙酯等的初始浓度可对氧化硅块体材料的孔径大小进行有效的调节。根据实验表征结果推测介孔材料的形成机理。 以水合金属为前驱体，通过乙醇介质中环氧丙烷的开环反应促使形成了块状金属氧化物凝胶。凝胶在常压下干燥并于700℃焙烧后得到介孔金属氧化物材料。根据表征结果对环氧丙烷参与的溶胶凝胶金属氧化物的合成机理进行了探讨。以硅溶胶为硅源，以乙二醇为软模板剂，成功合成了具有较大平均孔径，孔分布均匀的二氧化硅介孔材料，通过改变煅烧过程提高了介孔材料的比表面积并研究了乙二醇造孔过程。更多还原

【Abstract】 Nowadays microsphere and mesoporous materials are the hot-point of the research of material preparation. As the fast improvement of nano-material science, numerous new nano-material is synthesized and used in modern industry greatly. Microsphere and mesoporous, as the important part of nano-materials, are also receives more and more attention. In this paper, a new synthesis way is used to prepare the organic-inorganic composite microsphere and various mesoporous materials are synthesized by template method. The materials were characterized by BET, TEM, FTIR and DTA.The composite silica microsphere was obtained through the polymerization of urea and formaldehyde occurred in the silica sol that prepared from the hydrolyzation of tetraethyl orthosilicate. Through the test, it is found that the micro-structure of the microsphere can be changed by varies the molar ratio of the reactant and react condition. The microsphere synthesized as the molar ratio of formaldehyde to urea is two has a core-shell structure in it’s micro-structure, and one of the molar ratio of formaldehyde to urea is one has a network structure. And in the latter condition, the micro-structure of the microsphere is changed from the network structure to core-shell structure as the proportion of formaldehyde and urea in reactant decrease simultaneously. According the characterization the synthesize mechanism is put forward to.A simple one-step procedure is described for the synthesis of mesoporous monolith and composite powder, in which hydrolyzation of tetraethyl orthosilicate and polymerization of urea and glyoxal occurred at the same time. The experiment result show that the white powder only product as the molar ratio of glyoxal to urea is below one. When the molar ratio of glyoxal to urea is above one, the porous and surface areas adjustment of the mesoporous materials can be achieved by varies the molar ratio of the reactant. According the characterization the synthesize mechanism of the mesoporous materials is discussed.更多还原