White carbon black, also known as hydrated silicon dioxide, has a chemical formula of SiO2 nH2O. It is a white, non-toxic, amorphous fine powder inorganic silicon compound with porosity, high dispersibility, light weight, and good chemical stability. It has excellent properties such as high temperature resistance, non-flammability, and good electrical insulation, and has been widely used in many fields such as plastics, rubber, paper, coatings, dyes, and inks.
On the other hand, due to the presence of active silicon hydroxyl groups on the surface of silica, silica is hydrophilic and difficult to infiltrate and disperse in the organic phase, making it unusable in some special fields. However, the modified white carbon black greatly broadens the application field of the product due to the improved surface activity.

Let's take a look at which industries white carbon black is favored by.
01Application in tires
Silica is used as a reinforcing agent, and the largest amount is used in the rubber field, accounting for 70% of the total. Silica can greatly improve the physical properties of the compound, reduce the hysteresis of the compound, and reduce the rolling resistance of the tire without losing its wet skid resistance. In the rubber industry, carbon black is a very effective reinforcing agent, but its biggest disadvantage is that it cannot be used to prepare colored products. Ultrafine silica is used as a reinforcing filler for the production of green tires. It can replace carbon black in the sidewall, which can significantly increase the tear strength and crack growth resistance of the sidewall.
While there is no significant effect on the vulcanization time, the ozone aging resistance depends on the amount of antioxidant and silica. Adding white carbon black to the tread rubber of the tire can improve the cutting resistance and tear resistance of the tread, and reduce the jumping and falling blocks. Compared with the ordinary carbon black filled rubber compound, the rolling resistance of the silica filled compound can be reduced by 30%.

02Application in defoamer
Fumed silica generally has two types of products: hydrophilic type and hydrophobic type. Among them, the hydrophobic type is obtained by surface chemical treatment of the hydrophilic type. Now all defoamer manufacturers generally use hydrophobic type of fumed silica. Use the hydrophobic groups on its surface to attract the hydrophobic end of the surfactant in the foaming system, so that the hydrophobic solid particles become hydrophilic, thereby reducing the concentration of surfactants in the foam, promoting foam bursting, and improving defoaming speed.


03Application in paint and coating industry
Silica can be used as a rheological additive, anti-sedimentation agent, dispersant aid, and matting agent in the production of coatings to thicken, prevent sedimentation, thixotropy, and matting. Moreover, it can also improve the weather resistance and scratch resistance of the coating, the adhesion strength between the coating and the substrate and the hardness of the coating, the aging resistance of the coating, and the ultraviolet absorption and infrared light reflection characteristics.

04Application in electronic packaging
By fully dispersing the surface-active treated fumed silica in the silicone-modified epoxy resin encapsulation matrix, the curing time of the encapsulation material can be greatly shortened (2.0-2.5h), and the curing temperature can be lowered to room temperature , so that the sealing performance of the OLED device is significantly improved, and the service life of the OLED device is increased.
The addition of fumed silica reduces the process of packaging electronic devices that required special environments in the past to room temperature, greatly reducing production costs and shortening the curing time of packaging materials, greatly improving production efficiency and reducing production costs. It will promote the popularization and application of the new generation OLED display technology.


05Application in plastics
White carbon black is also often used in new plastics. Adding a small amount of white carbon black during plastic mixing will have a significant reinforcing effect and improve the hardness and mechanical properties of the material, thereby improving the processing technology and product performance. In addition, silica has the characteristics of small particle size and high light transmittance, which can make plastics denser and increase the transparency of plastics.

06 Application in Ceramics
Adding fumed white carbon black instead of nano-Al2O3 to 95 ceramics can not only play the role of nanoparticles, but also the second-phase particles, which not only improves the strength and toughness of ceramic materials, but also improves the hardness and elasticity of materials. Modulus and other properties, the effect is more ideal than adding Al2O3. Using fumed white carbon black to compound the ceramic substrate not only improves the compactness, toughness and smoothness of the substrate, but also greatly reduces the sintering temperature. In addition, the application effect of fumed silica in ceramic products such as ceramic filters and corundum balls is also very significant.


According to the editor of China Powder Network, it can also be used as a carrier to load Ti, Ag or Cu ions into ceramic materials by using its porosity, which can have an antibacterial effect, thereby preparing antibacterial ceramic sanitary ware.

Source: 粉末网
Disclaimer: The content contained in this article comes from public channels such as the Internet and WeChat public accounts. We maintain a neutral attitude towards the opinions in the article. This article is for reference and communication only. The copyright of the reproduced manuscript belongs to the original author and institution. If there is any infringement, please contact us to delete it.