① The more obvious difference is the different colors. Silica is white and can be used to make various colored products and transparent products: while carbon black can only be used to make gray and black products. ② Compared with carbon black, white carbon black has a higher surface area and finer particles. Large surface area means high activity, and vulcanizate has high tensile strength, tear strength, and abrasion resistance, but its elasticity decreases. Therefore, the viscosity of the mixed rubber increases and the processing performance decreases. The surface of silica has more micropores than carbon black, so the increase in the surface area of silica can not improve the rubber reinforcement as much as carbon black. The structure of white carbon black is also higher than that of carbon black. This is because the hydrogen bonding on the surface of white carbon black makes it form more agglomerates than carbon black. Therefore, the viscosity of high surface area and high structure white carbon black compound Very high, which is not good for processing. Precipitation white carbon black has silanol groups on the surface; vapor phase white carbon black also has silanol groups on the surface. The pH value of precipitation method silica is either acidic or alkaline: vapor-phase method silica is acidic.