Silane-modified low molecular weight ‘liquid’ polymers in sulfur cured mixtures of styrene-butadiene copolymers and silica

Abstract

Silane coupling agents are used in silica filled rubber compounds to increase the filer-polymer interactions and to lower the filler-filer interactions. In addition, silane functionalized polymers can be used. Special types of polymers are low molecular weight ‘liquid’ polymers. The goal of this paper is to obtain more understanding about the uses and effects of these low molecular weight ‘liquid’ polymers in combination with silanes and other compound components. Three different silane coupling agents and six different low molecular weight ‘liquid’ polymers were selected, evaluated and comparatively introduced in mixtures of a SSBR/silica compound. The Payne effect was measured to evaluate the strain dependence of the mixtures. It was used to evaluate the filler-filler interactions and estimate the micro dispersion. This provides information about the interactions and the building of additional networks that comprises the low molecular weight ‘liquid’ polymer together with the silica, silane and main polymer. Results of dynamic mechanical analysis are discussed. The microstructures and silane-functionalizations show clear dependences on the glass transition temperatures, loss moduli and tan δ values.

Keywords

• Liquid polymer
• Silane and silica
• Crosslinking
• Polymer and filler network
• Tire tread formulations