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Surface Treatment Of Titanium Dioxide For Masterbatch

Surface Treatment Of Titanium Dioxide For Masterbatch

Through proper organic surface modification treatment, certain properties of titanium dioxide can be greatly improved.
1 Chemical stability
After high-temperature calcination and inorganic coating, the titanium dioxide has very good chemical stability and basically does not undergo chemical reaction with various components in the plastic system. However, some organic treatment agents may participate in chemical reactions. Therefore, we should choose some chemically inert organic treatment agents, such as some special polysiloxanes or modified polysiloxanes, which have very good chemical stability in low temperature and high temperature environments, and will not Any additives in the masterbatch system chemically react.
2 Temperature resistance
Titanium dioxide is easily discolored due to lattice defects at high temperatures. A complete inorganic coating and a suitable organic film can greatly improve the temperature resistance of titanium dioxide. Traditional organic coating agents (such as TM P, TEP, PEG) are not resistant to high temperature, and are prone to yellowing and decomposition under high temperature environment. Many titanium dioxide manufacturers have encountered this “yellowing” problem in practical applications. . This traditional organic coating agent is not suitable for the organic coating of titanium dioxide for masterbatch applications. The decomposition temperature of some special silicone materials exceeds 350 degrees, and no color change occurs within 300 degrees, that is, yellowing does not occur. In addition, after this silicone material is coated on the surface of titanium dioxide particles, it can prevent the transfer of free radicals, thereby further improving the heat resistance and light resistance of titanium dioxide.
3 Mobility
The migration of titanium dioxide is mainly due to its poor wetting compatibility with the resin. When the temperature is lowered and the plastic products shrink, the movement speed of the resin and titanium dioxide is inconsistent. To reduce the mobility, it is necessary to improve the compatibility of titanium dioxide and resin. According to the principle of similar compatibility, the organic treatment agent on the surface of titanium dioxide preferably has the same or similar functional groups as the applied resin. For the most commonly used polyolefin plastics, it is more suitable to use organic treatment agents containing long-chain alkanes.
4 Dispersibility
The dispersion of titanium dioxide is mainly affected by intermolecular forces, polar adsorption, particle fineness and other factors. Titanium dioxide used for plastic masterbatch, the particle size of titanium dioxide is generally about 0.4 microns. Such fine particles have a huge specific surface area and Gibbs free energy, and are in a thermodynamically unstable state.

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