Effect of Compounding Ingredients on the Silica-filler Dispersion in Rubber Compounds

Abstract

Due to the poor surface energy of the silica-filler, silica surfaces are easily affected by the ingredients in the rubber compounds, for example, oil or cure accelerators. We confirmed the influence of oil and cure accelerator for silica-filler dispersion behavior in styrene-butadiene rubber on the bases of viscoelastic properties and the formation of the filler-gel. Our experiments showed that the interaction between silica surfaces and ingredients in the rubber compounds induced the acceleration of silica dispersion and that the size of aggregates or agglomerates in the silica-filled compounds depended on the amount of oil and the melting point of the cure accelerators. Moreover, we have discovered that the interactions between silica surface and ingredients exerted influence on the formation of the filler-gel, and on the modulus and viscoelastic properties of cured compounds.