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1) Relative density

Among the commonly used white pigments, titanium dioxide has the smallest relative density, and the largest surface area and the highest pigment volume of the same quality white pigments.

2) Melting and boiling points

Because anatase converts to rutile at high temperatures, the melting and boiling points of anatase titanium dioxide are virtually nonexistent. Only rutile titanium dioxide has melting point and boiling point. The melting point of rutile titanium dioxide is 1850℃, (1830±15)℃ in air, and 1879℃ in oxygen-rich titanium dioxide. The melting point is related to the purity of titanium dioxide. The boiling point of rutile titanium dioxide is (3200±300)℃, and titanium dioxide is slightly volatile at this high temperature.

3) Dielectric constant

Titanium dioxide has excellent electrical properties due to its high dielectric constant. The crystallization direction of titanium dioxide crystal should be considered when determining some physical properties of titanium dioxide. The permittivity of anatase titanium dioxide is relatively low, only 48.

4) Conductivity

Titanium dioxide has semiconducting properties, its electrical conductivity increases rapidly with temperature rise, and it is also very sensitive to hypoxia. The dielectric constant and semiconductor properties of rutile titanium dioxide are very important to the electronics industry and can be used to produce electronic components such as ceramic capacitors.

5) hardness

According to mohler hardness scale of 10, rutile titanium dioxide is 6 ~ 6.5, anatase titanium dioxide is 5.5 ~ 6.0, so in chemical fiber extinction to avoid wear spinneret hole and anatase titanium.

6) hygroscopicity

Although titanium dioxide has hydrophilic, but its hygroscopicity is not too strong, rutile is smaller than anatase. The hygroscopicity of titanium dioxide has a certain relationship with the size of its surface area, large surface area, high hygroscopicity, but also related to the surface treatment and properties.

7) Thermal stability

Titanium dioxide is a material with good thermal stability.

8) particle size

The particle size distribution of titanium dioxide is a comprehensive index, which seriously affects the properties of pigment and product application of titanium dioxide. Therefore, the discussion of covering power and dispersion can be directly analyzed from the particle size distribution.

The factors affecting the particle size distribution of titanium dioxide are complicated. The first is the size of original particle size of hydrolysis. The original particle size can be kept in a certain range by controlling and adjusting the hydrolysis process conditions. Secondly, the calcination temperature, in the process of calcination of mettitanic acid, particles undergo a crystal transformation period and growth stage, control the appropriate temperature, so that the growth of particles within a certain range. Finally, it is the crushing of the product, usually the transformation of Raymond mill and the adjustment of the speed of the analyzer, control of crushing quality, while other crushing equipment can be used, such as: universal mill, air mill and hammer mill device.