Titanium dioxide (TiO2) is a naturally occurring mineral that has been used in a variety of applications for a very long time. Over time, its utilization has expanded notably, especially in the plastics sector, due to its unique properties and ability to improve the appearance and performance of plastic products. In this article, TLD Vietnam will explore what titanium dioxide is and the benefits of using it in plastic.

What Exactly Is Titanium Dioxide?

Titanium dioxide, also known as titanium(IV) oxide or titania,  is a naturally occurring inorganic compound in the oxide form of titanium. It refers to the name titanium white, Pigment White 6, or CI 77891 when used as a dye. This substance holds a prominent status as one of the most widely utilized materials globally, boasting an annual production exceeding 4 million tons. 

Molecular Formula: O2Ti or TiO2

• Melting point: 1.843 °C
• Density: 4.23 g/cm³
• Molecular weight: 79,866 g/mol
• Boiling point: 2.972 °C

The Key Properties

Regarding its optical properties, thanks to its high refractive index, titanium dioxide has notable  opacity, whiteness, and brightness. Refers to chemical stability, titanium dioxide is chemically stable and does not react with most chemicals, including acids and bases. In terms of thermal stability, titanium dioxide is thermally stable and exhibits resilience against high temperatures, retaining its properties intact. Regarding electrical properties, it serves as an outstanding electrical insulator with low electrical conductivity.

The Common Applications Of Titanium Dioxide

Titanium dioxide is utilized in a multitude of industries due to its diverse properties. It serves as a crucial component in architectural, automotive, and industrial coatings, providing durability and UV resistance. In personal care products like sunscreens, it shield against harmful UV radiation. Additionally, in ceramics, titanium dioxide acts as a glaze, enhancing brightness and color stability. It’s also employed in paper production as a filler, improving opacity and printability. Furthermore, titanium dioxide nanoparticles serve as catalysts in various chemical reactions, ranging from organic compound oxidation to hydrogen gas production. Across these applications, titanium dioxide proves its versatility and indispensability in modern manufacturing processes.

Titanium Dioxide Used In Plastic

Improve the heat resistance

Titanium dioxide (TiO2) is commonly used as a white pigment in the plastic industry to enhance the heat resistance of plastic items. When added to plastic, TiO2 functions as a nucleating agent, promoting the formation of crystalline structures within the material. These crystalline structures provide reinforcement to the plastic, enhancing its strength and durability. At high temperatures, the crystalline structures become more stable and can better resist deformation and melting.

There are several ways that can be useful to improve the  heat resistance of plastics by using titanium dioxide

• Increase the melting point of plastic: Elevating the plastic’s melting point enables it to endure higher temperatures before reaching a state of melting, thereby making it more suitable for use in high-temperature applications.
• Improve the thermal stability of plastics: It helps plastics better resist deformation and degradation when exposed to high temperatures, thereby enhancing their durability and reliability

Improve the light resistance 

In addition to its heat resistance benefits, titanium dioxide also enhances the light resistance of plastics, helping them be more resistant to fading and discoloration when exposed to sunlight or other light sources.

Titanium dioxide enhances the light resistance of plastics by utilizing its capacity to scatter and absorb light. When added to plastic, titanium dioxide particles scatter light in all directions, reducing the amount of light that penetrates the plastic. 

The scattering and reflection of light by titanium dioxide particles serve as an effective shield, safeguarding the plastic from the detrimental impacts of light exposure.

Furthermore, titanium dioxide possesses a high refractive index, meaning it bends and decelerates light more than other substances.

This property allows titanium dioxide to disperse light evenly throughout the plastic, leading to a more uniform appearance and minimizing the risk of hotspots or uneven discoloration.

Enhance plastic weather resistance

Plastics are vulnerable to weather factors such as sunlight, moisture, and temperature fluctuations, which can cause them to degrade and lose their mechanical properties. Titanium dioxide can be seen as an effective additive, mitigating these effects and enhancing the weather resistance of plastics.

One of the primary ways in which titanium dioxide enhances the weather resistance of plastics is through its ability to absorb ultraviolet (UV) radiation. As a highly efficient UV absorber, TiO2, when incorporated into plastic, intercepts UV radiation from sunlight, impeding its penetration into the polymer chains.  

By absorbing the UV radiation, TiO2 prevents the formation of electron-hole pairs, slowing down the rate of photo-degradation and extending the lifespan of the plastic product.

Additionally, titanium dioxide serves as a barrier against moisture and other environmental elements. When added to plastic, TiO2 particles create a barrier that prevents moisture and other environmental factors from penetrating the plastic. This barrier mitigates the effects of weathering, such as cracking and warping, and shields the plastic from degradation caused by exposure to the elements.

Moreover, titanium dioxide can also be used as a filler material in plastics. In this role, it improves the mechanical properties of plastics, such as their stiffness, toughness, and impact resistance. This enhancement makes the plastic more resistant to the effects of weathering and other environmental factors, ultimately improving its overall weather resistance.

Coloring plastic

Titanium dioxide is a highly effective pigment. When added to plastic, it can make the product white, opaque, and highly reflective. This makes it widely used in the plastic industry for producing white masterbatch, which is used to color plastics white.

Titanium dioxide achieves its white pigmenting effect through a process known as Mie scattering. When light enters a plastic product containing TiO2 particles, the light waves interact with the particles and are scattered in all directions. This scattering effect is strongest in the short-wavelength range of visible light, which includes blue and violet light. Hence, TiO2 particles appear white in color, as they reflect all colors of visible light.

Improve the mechanical and electrical properties of plastic

In addition to its role as a pigment, it is utilized to enhance the mechanical and electrical properties of plastic. When integrated into plastic formulations, TiO2 can enhance the strength, stiffness, toughness, and impact resistance of the material, making it more durable and resistant to deformation.

TiO2’s capacity to function as a reinforcing filler is one of the main factors contributing to its ability to enhance the mechanical properties of plastic. This happens as a result of the minuscule TiO2 particles’ ability to engage with the plastic’s polymer chains and forge a more robust and rigid structure. Due to the increased surface area of TiO2 particles, there are more points of contact between the particles and the polymer matrix, which improves the material’s mechanical properties.

In addition to mechanical properties, TiO2 can also improve the electrical properties of plastic. This is because TiO2 is an effective insulator and may aid in lowering the electrical conductivity of plastic items. Under some circumstances, TiO2 may also function as a dielectric or a substance that can store and discharge electrical energy.

Using TiO2 as a plastic addition also has the benefit of enhancing the material’s dimensional stability. This is crucial in situations when exact dimensions and tolerances are necessary, such as when making machine components or molds. TiO2 may be used to prevent plastic shrinkage during cooling and curing, resulting in a more consistent and predictable end product.

In short, the benefits of using titanium dioxide in plastic are numerous and significant. This naturally occurring mineral is able to enhance the performance and quality of plastic products. By adding titanium dioxide to plastic, manufacturers can create stronger, more durable, and more aesthetically pleasing products that are able to withstand exposure to sunlight, heat, and other environmental factors. 

In Conclusion

Titanium dioxide emerges as a remarkable solution to the pressing challenges faced by the plastic industry. Through its diverse applications and unparalleled properties, titanium dioxide not only enhances the performance and aesthetics of plastic products but also contributes significantly to environmental sustainability.