Preparation And Modification Of TiO₂ Particles And Their Pigment Properties

Titanium dioxide has the advantages of high refractive index,high achromatic force,good gloss and whiteness and become the best white pigment,widely used in coatings,plastics,paper,ink and chemical fiber etc.Because of the photocatalytic activity of titanium dioxide,especially rutile titanium dioxide,the organic component of the catalyst can be degraded in the course of use.Untreated titanium dioxide used in paint,coating and powder have lost the light off phenomenon,used in plastic or decorative paper products,surface crack,yellowed,seriously reduce the performance and service life of the product.Therefore,the TiO₂ particles were coated by surface treatment technology,the formation of core-shell structure particles in TiO₂ coated with a layer of inert material for photochemical barrier,reduce the photochemical activity of TiO₂,improve the TiO₂ particle dispersion,weatherability,gloss and hiding power.The study on the preparation of the core shell structure of titanium dioxide is of great significance to the development of high titanium pigment.Liquid phase chemical deposition method was used to prepare TiO₂@SiO₂,TiO₂@Al₂O₃ monolayer core-shell particles.The effects of the coating temperature,the amount of coating and the coating method on the coating were studied by orthogonal experiment.Based on the particle size distribution of the coated samples and the results of SEM and TEM detection,and the properties of the pigment,the best monolayer coating process was obtained.TiO₂@SiO₂@Al₂O₃ core-shell structure was prepared,and the optimum process of composite coating was obtained by combining the results of temperature and oil absorption of the composite coating.It was found that,The optimum reaction temperature for preparing TiO₂@SiO₂@Al₂O₃ is 80?.Two kinds of coating agent are added to the reaction kettle simultaneously?Sulfuric acid is used as neutralizing acid;The pH of silicon coating is 8⁹,silicon content is 1%,the amount of aluminum is 2.5%,aluminum coating pH is 9¹0.Finally,the high temperature resistant titanium dioxide pigment was obtained.The TiO₂ core shell structure with different metal elements was prepared,and the core-shell structure of TiO₂@AlPO₄ monolayer was prepared.By using field emission scanning electron microscopy?SEM?,transmission electron microscopy?TEM?analysis,laser particle size analyzer,light fastness test methods for the preparation of core-shell structure particles,coated titanium dioxide can draw the elements of high light.Study on the influence of the preparation process of core-shell structure and titanium dioxide pigment light.The experiment showed that cerium and phosphorus significantly improve the light fastness of titanium dioxide particles.The composite coating temperature is 80degrees,and the coating mode of aluminum phosphate is parallel flow,and the coating pH is 9¹0.The TiO₂@CeO₂@AlPO₄@Al₂O₃ multilayer core-shell structure was prepared,which was used in decorative paper.Light fastness of titanium dioxide is an important indicator of weathering resistance of titanium dioxide.The author invented a new method of simple testing of light fastness of titanium dioxide.The results show that the fast detection method has great correlation with the existing test results;it can be used as a fast effective method for rapid detection of light fastness of titanium dioxide.