【作者】 蒋莉；

【导师】 赵石林；

【作者基本信息】 南京工业大学 ， 高分子材料， 2003， 硕士

【摘要】 随着工业化进程的加快和发展所造成的环境恶化，特别是大气污染，已成为亟待解决的城市环保问题之一。纳米TiO₂具有无毒，催化效率高、性能稳定、等突出特点，可以用于光催化净化空气，它已成为目前光催化研究领域中最活跃的方向之一。本文重点研究了纳米TiO₂粒子的分散并制备了纳米TiO₂光催化净化空气涂料，表征了其性能。 首先讨论了在纳米TiO₂在水中的分散情况，研究分散剂种类和用量、pH值、分散方法、及分散时间对纳米TiO₂水分散体稳定性的影响，用分光光度计和粒子尺寸分布仪进行了表征，证实采用分散剂A，用量为1％，pH值为10，加入5％的纳米TiO₂粒子，高速搅拌2hr的方法可以获得分散性能优良的纳米TiO₂水分散体。另外还研究了分散剂的用量对纳米TiO₂溶剂体系的影响。 本文使用纳米TiO₂制备了溶剂型纳米光催化净化空气涂料。通过接触角仪比较了不同晶型和不同型号的纳米TiO₂以及颜料级TiO₂光催化能力的差别，并利用红外光谱证实在纳米级光催化涂料的表面产生了具有很强光催化作用的氢氧自由基。研究了光照时间、甲醛气体初始浓度、涂料中纳米TiO₂粒子的含量等对内外因素甲醛气体的光催化降解率的影响，还比较了氟树脂和有机硅树脂纳米光催化涂料的净化效果。测试了光催化净化空气纳米涂料的基本性能，并且研究了颜基比对涂料硬度的影响。纳米TiO₂在氟树脂中的添加量为46wt％（即颜基比为3：7）时，对甲醛气体的光降解率4小时后达到了55.2％，随着时间的延长其降解率还在下降。用涂膜切片的SEM照片证实了涂膜中纳米TiO₂粒子的粒径多在100nm左右，且其基本性能也符合或高出相关国家标准的要求，可用来净化空气中的污染性气体。更多还原

【Abstract】 The deterioration of environment,especially the atmosphere pollution, resulting from the increasing and developing of industrialization, has become one of the city’s environment protection problems which is in need of earnestly solving.With its renewal ability and storability of energy and friendliness of environment, nano-semiconductor TiO2 is the very novel green purificant.Now its relevant study becomes the focus of the field of photocatalysis, especially in exhaust gas treatment. In this paper, dispersion of nano-particles in water was mainly investigated, and photocatalysis air-purifying coatings containing nanometer TiO2 photocatalyst were prepared, their performances were tested.Such factors as category and content of dispersant, pH, disperse manner and disperse time, has effect on the stability of nano-TiO2 aqueous dispersion. The stability of dispersion has been in token of spectrophotometer and laser particle-sizer. It is proved that when condition is dispersant A =1%, pH =10, particle content = 5%(wt%), mixing around under high speed for two hours, excellent stable nano-TiO2 aqueous dispersion can be acquired. In addition, the stability of nano-Ti02 solvent dispersion is discussed.In this paper, nanocomposite photocatalytic coatings have been prepared by use of photocatalytic property of nano-TiO2. By water contact angle meter, photocatalytic ability of several kinds or crystal form of TiO2 has been compared. In addition, OH and OH~ have been proved to be in existence on coating surface by FTIR.The effect of illumination time, nano-TiO2 content in the coating, initial concentration of formaldehyde etc.on the photodegradation efficiency on HCHO were disscussed. The effect of nano-TiO2 amount on viscosity, hardness and other applied performance of the coatings we prepared were discussed. Solvent-based photocatalysis air-purifying coatings containing nanometer TiO2 photocatalyst using fluororesin and silicone resin were prepared. When the particle content of nano-TiO2 is 46wt%(namely pigment binder ratio is 3:7), degradation rate of the coating onHCHO after 4 hours is average 55.2%. Particles size of nano-TiO2 in the coatings is mainly around 100nm testing by SEM photo, and the basic performance of this kind of solvent-based photocatalysis air-purifying coating containing nanometer TiO2 photocatalyst accorded with or excel correlative national standard.更多还原