Titanium Dioxide Toxicity-Are There Different Types Of Titanium Dioxide
Yes, there are different types of titanium dioxide (TiO2), which are categorized based on their physical properties, such as particle size, crystal structure, and surface treatments. Here are some of the main types:
1. **Anatase**: This is one of the most common forms of titanium dioxide. It is characterized by a tetragonal crystal structure and is often used in applications such as paints, coatings, and plastics due to its excellent opacity and whiteness.
2. **Rutile**: Rutile is another crystalline form of titanium dioxide, featuring a trigonal crystal structure. It is known for its superior refractive index and is typically used in applications where high durability and UV resistance are required, such as in sunscreens and outdoor paints.
3. **Brookite**: Brookite is a less common form of titanium dioxide, with an orthorhombic crystal structure. It is not as widely used as anatase or rutile due to its lower physical stability and opacity.
4. **Amorphous Titanium Dioxide**: This form does not have a defined crystal structure and is produced by certain methods that result in a disordered atomic arrangement. It can be used in applications where specific textural or catalytic properties are needed.
In addition to these crystal forms, titanium dioxide can also be modified through various treatments:
– **Surface Treatments**: These are applied to improve the dispersibility, compatibility, and stability of TiO2 in different matrices. For example, surface treatments with silanes, aluminates, or titanates can enhance the performance of TiO2 in coatings and plastics.
– **Pigment Grades**: These are designed for use as white pigments in paints, plastics, and papers. They are often surface-treated to optimize their properties for specific applications.
– **Specialty Grades**: These include grades tailored for specific uses such as catalysts, food additives (E171), and in the production of electronic materials.
The choice of type and grade of titanium dioxide depends on the specific application and the desired properties.