The Role of the Organic Coating of Titanium Dioxide
The main role of the organic coating is to improve the wetting, dispersion and rheological properties of the titanium dioxide in various media, to reduce the absorption of water during storage and to reduce the adhesion of the pigment. The mechanism is to change the surface properties of the titanium dioxide particles.
There are two main ways to connect the organic treatment agent to the surface of the titanium dioxide particles: one is physical adsorption, because the organic coating agent is mostly a surfactant, the molecule is generally composed of a hydrophilic polar group and an oleophilic non-polar group, when it comes into contact with the organic titanium dioxide particles, its polar group will be adsorbed on the surface of the titanium dioxide particles, so that the non-polar group is exposed to form an organic film with the affinity of the paint base, thus making the interface The tension of the interface is reduced, so that the titanium white particles in the organic medium is free, the pigment particles are separated from each other to achieve the effect of dispersion; another way is chemical adsorption, that is, it reacts with the hydroxyl group on the surface of titanium white and associates with it.
