电子墨水用纳米TiO2白色颗粒的制备

Preparation of nano-TiO2 white particle used in e-ink

以Ti（OC4H9）4为原料，在溶有聚乙烯醇或聚乙烯吡咯烷酮分散剂的溶液中直接水解、胶溶，制备出单分散性、热稳定性良好，平均粒径在500nm的电子墨水用TiO2纳米微粒。研究了Ti（OC4H9）4浓度、水解时间、溶剂加入方式对纳米微粒粒径的影响。对样品进行了TG-DTA，XRD和SEM分析。结果表明：样品经真空干燥后，TiO2粉体主要为无定形胶体，随焙烧时间增加和温度升高，在450℃粉体从无定形向锐钛矿型转变，在900℃保温3h从锐钛矿型向金红石型转变，粉体粒径也有一定增大，1200℃保温3h，仅含有金红石相，粉体为实心球体，表面光滑。

Nano-sized TiO2 particle used in e-ink was prepared by direct hydrolysis of Ti（OC4H9）4,colloidal sol in the mixture solution contained alcohol and polyvinyl alcohol. The particle is of good single dispersion and thermal stability, and its diameter is about 500nm. The concentration of Ti（OC4H9）4, hydrolysis time and solvent add mode have a large influence on particle diameter. The particle was investigated by DTA-TC XRD and SEM analysis. The results show that the TiO2 particle is mainly amorphism after being dried under vacuum. With the increase of calcining time and the rise of temperature the content of rutile increases and the diameter of the particle also becomes big. The TiO2 particle crystallization happens at 450℃, the transforming temperature from anatase to rutile is 1200℃, and the crystalline phase of powders is rutile completely after sintered at 1200℃ for 3h, the particle is solid sphere with smooth surface.