羧酸改性钛白粉促进光固化研究

采用油酸对商用二氧化钛进行表面改性，通过 X-射线光电子能谱仪（ XPS）、红外光谱（FT-IR）和 X射线粉末衍射分析（ XRD）对改性后的 TiO₂粒子进行了结构表征，并借助热重分析测定了改性剂的含量。采用光差示扫描量热法（ photo-DSC）研究了无机膜保护型 TiO₂、去包膜型 TiO₂、油酸改性 TiO₂和三甲基苯甲酰二苯基氧化膦（ TPO）对丙烯酸酯光聚合动力学的影响。结果表明：油酸改性的 TiO₂与无机膜保护的 TiO₂和去包膜的 TiO₂相比，能在空气中引发丙烯酸酯的光聚合，并能增强以 TPO为光引发剂的丙烯酸酯的光聚合，从而在相同固化效果下，可减少小分子光引发剂的添加，降低残留。本研究为后续紫外光（UV）固化白色涂料、油墨固化不完善等问题提供了解决途径。

Study on Photocuring Process Enhanced by Carboxylic Acid Modi. fied Titanium Dioxide

The surface of commercial titanium dioxide was modified by oleic acid. The surface structure of modified titanium dioxide particles was characterized by X-ray photoelectron spectroscopy（XPS）， infrared spectroscopy（FT-IR） and X-ray diffraction analysis（XRD）. The amount of oleic acid immobilized on TiO₂ particle was determined bythermogravimetric analysis. The influence on photopolymerization kinetics of acrylate were evaluated with Photo-DSC，including the inorganic coated TiO₂，coat removed TiO₂，oleic acid modified TiO₂ and trimethylbenzoyl diphenylphosphine oxide（TPO）， respectively. It was shown that the oleic acid modified TiO₂ could substantially initiate photopolymerization of acrylate under air，compared to the inorganic coated TiO₂ or coat removed TiO₂，and also enhanced the photopolymerization of acrylate with TPO as photoinitiator，while reduced addition of small molecule photoinitiator and reduced the residue at the same curing degree.This study provided further solutions to the problems such as the incomplete curing of white coatings and inks cured by ultraviolet .