Application Of Zinc Isooctanoate In Reducing Agglomeration Of Silica

- Apr 17, 2019-

In order to improve the mechanical strength, wear resistance and wet skid resistance of the tire, it is necessary to add a large amount of filler reinforcing agent white carbon black to the rubber. Due to the large amount of silanol groups on the surface of silica, these groups tend to aggregate and agglomerate, which is difficult to uniformly disperse during tire processing, and the Mooney viscosity of the rubber compound tends to rebound, thereby affecting the mechanical properties. Therefore, the technical form of adding a white carbon black dispersant or an active agent during rubber kneading improves the chemical properties of the silanol group on the surface of the white carbon black, improves the surface activity of the white carbon black, achieves good dispersion in the rubber, and further improves Or to improve the physical and chemical properties of the compound has achieved very significant efficacy.

At present, there are generally three types of processing aids for dispersing silica in rubber: alcohol and alcohol amine active agents, zinc soap dispersants, and silane coupling agents. Alcohol and alcohol amine active agents are usually adsorbed by polar silanol groups on the surface of silica during rubber compounding. The adsorption process is the process of polar self-shielding of silica-based silanol groups, which makes the vulcanization properties of the rubber compound. Undisturbed. The action mechanism of the zinc soap dispersant is to utilize the activity of hydrogen ions on the silanol group on the surface of the silica, and to carry out cation replacement with it, thereby reducing the polarity of the surface of the white carbon black, controlling the binding of the white carbon black ions, and reducing the glue. The Mooney viscosity is improved to improve the processing performance. However, such dispersants have little effect on improving the physicochemical properties of vulcanizates. The silane coupling agent not only improves the processing properties of the silica rubber compound, but also greatly improves and improves the physical and chemical properties of the vulcanized rubber of the silica filler compound. However, the coupling agent does not completely solve all the problems of the application, and a large amount of high-salt organic wastewater is generated in the production process of the silane coupling agent, which is serious to the environment and relatively expensive.

It has been found through research that zinc isooctanoate can reduce the polarity of silanol groups on the surface of silica, and the addition of zinc isooctanoate to silica can well prevent the agglomeration of silica and act to disperse white carbon black. With the support of this effect, zinc isooctanoate can be used in the application field of multiple white carbon blacks to disperse white carbon black and prevent its agglomeration, for example, in the field of rubber products containing white carbon black, white The role of carbon black dispersant. In addition, zinc isooctanoate can also be combined with other ingredients to form a white carbon black dispersant with various functions, which can not only disperse the white carbon black, but also improve some properties of the rubber compound.