Surface Organic Modification of TiO2 Powder and Relevant Characterization

Surface organic modification was conducted to TiO 2 with modifiers to improve the dispersity and comparability of pigment TiO 2 in application system by adjusting particle surface characteristics. Then, modification effects were characterized according to the changes in wetting contact angle and activation index of TiO 2 before and after modification. Moreover, the modification mechanisms of sodium stearate and sodium oleate were studied by analyzing the characteristics of TiO 2 surface functional groups in modification system and effects of modifiers. The results showed that, after being wet-processed with sodium stearate and sodium oleate, TiO 2 could turn from surface hydrophilic to inductive hydrophobic with controllable degree. The wetting contact angle of modified TiO 2 increased from 7° to 125.6° and 121.3°, respectively. The dispersity of TiO 2 in organic medium was stronger than that in inorganic medium. The modifiers formed absorption with chemical property on TiO 2 particle surface, so the inductive hydrophobicity of surface was stable.