Saiedeh Kazemi - Department of Chemistry, Amirkabir University of Technology, Tehran, Iran.
Ali Asghar Katbab - Department of Polymer Engineering, Amirkabir University of Technology, Tehran, Iran.
Majid Abdouss - Department of Chemistry, Amirkabir University of Technology, Tehran, Iran.

Silica provide many advantage for silica filled rubber compound such as natural color, improvement in the tyre durability and wet grip, lower hysteresis loss, and a lowerrolling resistance, leading to fuel savings as compared to the case of carbon black for tire applications [1]. Howeverprecipitated Silica has a number of hydroxyl groups, which results in strong filler-filler interactions and particle aggregation. So it cause adsorption of curatives and reduce thecure torque of rubber compounds containing silica. Precipitated silica has a poor chemical affinity and dispersion in a non polar rubber compound like styrene–butadiene [2]. Therefore, surface treatments are needed to improve the reinforcement of the composites [3]. Among the surfacemodification techniques of the silica, silane coupling agents have been mostly used in the rubber industry. In the present study two different materials have been employed to modify the surface of Precipitated nanosilica in Silica/SBR nanocomposites [4]. These include: Poly Ethylene Glycole and 3-Aminopropyl triethoxy silane.