Physical properties of rutile type titanium dioxide

Coatings industry:
Rutile titanium dioxide, as one of the two most important types of titanium dioxide, is an excellent white pigment with high dispersibility, high weather resistance, high hiding power, and good stability. It is widely used in interior and exterior wall latex paints, industrial coatings, composite inks, flexographic printing inks, laminated paper, plastic masterbatch, powder coatings, etc. So, what are the physical properties of rutile titanium dioxide?
01
Relative density
The relative density of titanium dioxide is related to its crystal morphology, particle size, chemical composition, and especially the amount of surface treatment. During the manufacturing process, it increases with the increase of calcination temperature and the extension of calcination time. Among the commonly used white pigments, titanium dioxide has the smallest relative density. Among white pigments of the same quality, titanium dioxide has the largest surface area and the largest pigment volume. The relative density of rutile titanium dioxide is 3.8-3.9g/cm3, while the relative density of flake titanium dioxide is 4.2-4.3g/cm3.
02
Melting point, boiling point
Since both rutile and flake titanium dioxide will transform into rutile at high temperatures, their melting points and boiling points do not actually exist. The melting point of rutile titanium dioxide is inconsistent in various records, and is generally believed to be between 1800 and 1875°C. Data show that the melting point in air is 1830±15°C, and in oxygen-rich conditions it is 1879±15°C. The melting point is related to the purity of titanium dioxide. The boiling point of rutile titanium dioxide is (3200±300)K.
03
Dielectric constant
Due to the high dielectric constant of titanium dioxide, it has excellent electrical properties. Under the action of an external electric field, ions interact with each other to form an extremely strong local internal electric field. Under the action of this internal electric field, the outer electron orbits of the ions are strongly deformed, and the ions themselves are also significantly displaced.
The trace impurities contained in the titanium dioxide crystal form have a significant effect on the dielectric constant. The dielectric constant of the rutile type varies with the direction of the titanium dioxide crystal: when parallel to the C axis, its dielectric constant is measured to be 180; when it is at right angles, it is 90; the average value of its powder is 114. The dielectric constant of rutile titanium dioxide is only 48.
04
Conductivity
Titanium dioxide has semiconductor properties, and its conductivity increases rapidly with increasing temperature, and it is also very sensitive to oxygen deficiency. Rutile titanium dioxide is still an insulator at 20°C, but when heated to 420°C, its conductivity increases 107 times; the conductivity of stoichiometric titanium dioxide (TiO2) is less than 10-10s/m, and when a small amount of oxygen is lost, the conductivity of TiO2 such as TiO2 1.9995 can reach 10-1s/m. The electronics industry often uses the dielectric constant and semiconductor properties of rutile titanium dioxide to produce electronic components such as ceramic capacitors.
05
Hardness
If a 10-point Mohs hardness tester (which only represents the hardness grades of various crystals, not their true proportions) is used to measure the hardness of rutile titanium dioxide to be 5.5-6.0, and the hardness of non-rutile titanium dioxide to be 6-7. Hardness is related to the crystal structure of titanium dioxide, and in production it is also related to the purity and calcination temperature of the product. Sintering is easy to occur at high temperatures, and the hardness increases accordingly. It is precisely because rutile titanium dioxide has high hardness and is not easy to crush, and has a high wear rate on the spinneret holes and rollers, that it is not suitable for chemical fiber matting and gravure printing.
06
Hygroscopicity
Although titanium dioxide is hydrophilic, its hygroscopicity is not very strong, and the hygroscopicity of rutile is slightly greater than that of rutile. The hygroscopicity of titanium dioxide is related to the properties of the treatment agent during surface treatment, and also to the size of its specific surface area. Titanium dioxide with a large specific surface area also has a slightly higher hygroscopicity.
07
Thermal stability
Titanium dioxide is a thermally stable compound. When strongly heated under vacuum, a slight deoxidation reaction will occur, accompanied by a dark blue color. This reaction is reversible and will return to its original white color after cooling.
The above are the physical properties of rutile titanium dioxide that we have listed for you. You can submit the following form to obtain more industry information we provide for you.