【作者】 程学群；

【导师】 林安；

【作者基本信息】 机械科学研究院 ， 材料学， 2003， 硕士

【摘要】 纳米粒子应用于涂料中组成新型功能复合涂料，已成为研究的热点。但是由于纳米粒子表面极强的活性，使它们很容易团聚在一起从而形成带有若干弱连接界面的尺寸较大的团聚体，这大大降低甚至消除了纳米颗粒的实际应用效果，同时由于纳米粒子表面亲水疏油，在有机高分子树脂中难于均匀分散，界面上会出现空隙，当空气中的水分进入空隙中就会触发界面处高聚物的降解、脆化，导致涂层失效。所以，必须对纳米粒子进行表面改性，削弱或者消除团聚现象，提高纳米粒子在有机高分子中的分散性。近年来，对纳米氧化物表面改性已有不少的相关报道和应用。随着近年来对微波技术研究的深入，人们发现把微波技术用在化学反应上往往可以产生意外的效果。本文即是试图探讨纳米TiO₂粒子改性两种方法，一是用月硅酸钠通过物理吸附作用对纳米TiO₂粒子进行改性，此工艺改性产物不稳定。另一种方法是利用微波作为加热装置的纳米TiO₂粒子表面改性工艺以及分析其改性机理。实验结果表明：以微波为纳米粒子改性工艺的加热装置，既可以为反应提供热源，同时又有效的抑制了纳米粒子的长大。通过对改性后粒子的性能进行测试发现用油酸作为纳米改性剂可以很好的改善纳米粒子的表面性质。最佳改性工艺为：每2克纳米二氧化钛使用50ml油酸，改性剂浓度为V_油酸／V（正丁（?））=1／2，改性时间为先满功率辐射3分钟，然后小功率辐射半小时，经改性后的纳米TiO₂表面亲油性大大增强了。对产物进行红外光谱分析证明本改性试验产物中梭酸根离子和Ti离子是以鳌合的方式结合的;对产物进行热重和差热分析测试包覆率达到了29.14%。产物是在二氧化钦无机内核表面包裹了一层表面有机修饰层。把改性后的纳米TIO:添加到环氧树脂涂料中发现，涂层的结合力、耐盐雾性、抗划痕性和柔韧性能大大提局。更多还原

【Abstract】 Nano-partical has applied preliminary in the field of the functional coatings,. But for the strong activity of Nano-TiO2, the conglobation will happen easily, and it will greatly reduce the application effect in coating. And for the hydrophilicity , it’s hard to break up uniform in resins, so air gaps appear in the interface, then the high polymer in the interface willhappen degradation reaction or embrittlement reaction, and coatingsperformance will fall down. So, in order to increase the dispersity of theNano-partical in coatings, it’s necessary to modify the surface of Nano-partical. At present, some research documents and application have been given about the modification of nano-partical. With the developing of Microwave technology, wonderful effect happened when the Microwave technology was used in chemical reaction. A new process on surface modification of Nano-partical was studied in this paper, microwave was used as the heater equipment in this process. The results showed: the microwave supplied enough energy for the chemical reaction, and controlled the growth of Nano-partical. The experiments proved that it’s effective of using oleic acid to modify the surface of Nano-TiO2 particle. The best modification process is: 25ml oleic acid for per gramme Nano-TiO2 particle, modification agent is v油酸/v正丁=1/2, modification time is 3min with full power, then 30min with small power. After beenmodified, the Nano-TiO2 particle shows better lipophilicity. It was proved that the combine between carboxylic acid group and TiO2 particle is chelation by analyzing infra-red spectrum. The total clad ratio reached 29.14% by measuring TG-DTA curve. The final result is TiO2 particle being surrounded by organic carbon chains. The performances of cohesion, corrosion resistance, flexibility and shock strength increase when nano-TiO2 be added.更多还原