【作者】 万涛；

【导师】 王跃川；

【作者基本信息】 四川大学 ， 材料学， 2006， 博士

【摘要】 纳米TiO₂的热稳定性好、比表面大，具有光催化活性和折光指数高的特性，对可见光透过率高，而对紫外光吸收强，因此TiO₂杂化材料在光学材料、非线性材料、光折变材料、信息存储材料和三维图像显示材料、光屏蔽材料、太阳能电池、光催化降解材料等得到了广泛的应用。但是现有的聚合物基TiO₂杂化材料的研究主要集中于纳米粒子直接分散法和溶胶—凝胶法。采用纳米粒子直接分散法，有机相和无机相易产生相分离，严重影响杂化材料的透明性，因此一般需对纳米粒子进行表面改性，但反应时间长、反应温度高，工艺烦琐。而采用溶胶—凝胶法合成TiO₂杂化材料，由于钛酸丁酯的水解速率极快，易产生沉淀和絮凝现象，因此探寻新的方法或途径仍然是有机—无机杂化材料研究的热门课题。我们提出了集纳米粒子的制备与表面改性于一体的反胶束溶胶—凝胶法和原位光聚合制备聚合物基杂化材料的构想，首先采用丙烯酸单体与钛酸丁酯反应，形成羧酸钛配位键以抑制钛酸丁酯的水解速率，同时采用反胶束溶胶—凝胶法使钛酸丁酯的水解缩合反应限制在反胶束“水池”中进行，以得到稳定性好、粒径分布窄的纳米TiO₂粒子，然后采用光聚合法低温快速合成纳米TiO₂-聚丙烯酸酯杂化薄膜，原位形成的大分子网络可进一步抑制纳米粒子的团聚、聚集和絮凝，通过羧酸钛配位键在有机和无机相间形成化学键的连接，抑制了宏观的相分离，得到透明的杂化薄膜，最后的后期热处理可促进TiO₂纳米粒子表面钛羟基的进一步缩合反应，以提高TiO₂的含量和折光指数，得到了耐热、耐光、折光指数可调的TiO₂-聚丙烯酸酯杂化材料，在光学材料、非线性材料、光折变材料、信息存储材料和三维图像显示材料、光屏蔽材料等领域具有潜在的应用前景。本论文的主要研究结果如下： （1）首次以石油醚为油相，系统研究了醇含量、油含量以及氧化还原引发剂（NH₄）₂S₂O₈—NaHSO₃浓度、丙烯酸、丙烯酰胺单体浓度等多种因素对CTAB体系和SDBS体系微乳液溶水量和微乳液结构、渗滤阈值以及渗滤温度的影响。实验结果表明，通过改变丙烯酸和丙烯酰胺浓度，可改变溶水量，改变微乳更多还原

【Abstract】 Titanium dioxide hybrid materials have been widely used in the areas of optic, nonlinear, photorefractive, holographic storage, UV absorbent, solar cell and photocatalytic materials because of its high thermal stability, high surface area, high photocatalysis, high refractive index and good visible light transmittance and high UV light absorbance. However, most of the polymer-based titanium dioxide hybrid materials are concentrated on the methods of direct nanoparticles dispersion and sol-gel process. For the former, there exist severe inorganic and organic phase separation and thus remarkably affect the transparency of the materials. So the surface modification of the nanoparticles is needed by way of time-consuming and complex process at high temperature. For the latter, direct precipitation happen due to the fast hydrolysis of Ti precursor. Therefore seeking a new synthesis method of hybrid materials is a hot topic wordwide. We bring forward a new synthesis method of hybrid materials by way of sol-gel process in reverse micelles and subsequent photopolymerization, with characteristics of in situ nanoparticle formation and surface modification. That is, we use acrylic acid as an organic ligand to react with titanite butoxide (TTB) to control the hydrolysis rate of TTB. At the same time, the hydrolysis and condensation reaction can be limited within the nanoscale reverse micelles "water pool" and the stable titanium dioxide nanoparticles can be obtained with narrow size distribution and then be exposed to rapid photopolymerization to further control the aggregation, conglomeration and flocculation by organic networks formed during photopolymerization.The carboxylic bidentate coordination bridges the organic phase and inorganic phase, and retrains the microseparation between them, therefore the transparent hybrid更多还原