The effect of white carbon black on rubber properties is multifaceted, which can be summarized and explained in detail from the following aspects:

1. Effect on the mixing process
Dispersion: White carbon black particles are small, highly active, and hydrophilic, so it is not easy to disperse evenly during mixing. When mixed in large quantities, a large amount of gel is easily generated, which hardens the rubber and generates more heat. In order to improve the dispersion effect, it is recommended to add white carbon black in small batches and appropriately increase the mixing temperature. High temperature can remove part of the water adsorbed on the surface of white carbon black, reduce the cohesion between particles, and thus improve the dispersibility.
Heat generation: Since white carbon black is easy to generate gel during the mixing process, heat generation increases. Properly controlling the amount added and increasing the mixing temperature can effectively reduce heat generation.

2. Effect on the Mooney viscosity of the rubber
Mooney viscosity increase: As the amount of white carbon black filling increases, the Mooney viscosity of the rubber will increase. This is because white carbon black combines with rubber molecules to generate gel, which hinders the activity of rubber molecules and their chain segments. The increase of Mooney viscosity will lead to a sharp decrease in adhesion, so more softeners may be needed in practical applications.

3. Impact on the vulcanization process
Delayed vulcanization effect: White carbon black particles are small and have a large specific surface area. The -OH groups on its surface have a strong adsorption effect on the accelerator, so it has a significant delayed vulcanization effect. In order to weaken this effect, the amount of accelerator should be appropriately increased, or substances that can preferentially adsorb with -OH groups (such as diethylene glycol, triethanolamine, polyvinyl alcohol, etc.) should be added.
Vulcanized rubber properties: The reinforcing effect of white carbon black on vulcanized rubber depends on its particle size and the number and nature of -OH groups contained on the surface. The smaller the particle, the greater the reinforcing effect. Vulcanized rubber containing white carbon black has higher tensile strength and tear strength, less heat generation, good heat resistance and electrical insulation, but larger permanent deformation.

4. Impact on the physical properties of vulcanized rubber
Tensile strength and tear strength: White carbon black can significantly improve the tensile strength and tear strength of vulcanized rubber. After adding fumed silica to silicone rubber, the tensile strength can be increased by about ten times.
Heat resistance and electrical insulation: Silica gives vulcanized rubber good heat resistance and electrical insulation.
Permanent deformation: The permanent deformation of vulcanized rubber containing silica is relatively large, which is an aspect that needs attention.
V. Application in tires
Improve overall performance: The use of silica in the production of off-road tires, engineering tires, radial tires, etc. can significantly improve the overall performance of tires and increase mileage.
Reduce rolling resistance: Using silica to replace carbon black can effectively reduce the rolling resistance of tires and reduce fuel consumption. For example, the use of all-silica tread rubber can reduce rolling resistance by 20% and tread hysteresis by about 50%.
Improve safety performance: Silica can also significantly improve the anti-skid performance and safety performance of tires.

In summary, the effect of silica on rubber performance is significant, with both positive aspects (such as improving tensile strength, heat resistance, electrical insulation, etc.) and aspects that need attention (such as delayed vulcanization, large permanent deformation, etc.). In practical applications, the appropriate type and amount of silica should be selected according to specific needs, and appropriate process measures should be taken to give full play to its advantages.