Fillers for the rubber industry

Reinforcement of elastomers by colloidal fillers, like carbon black or silica, plays an important role in the improvement of the mechanical properties of highperformance rubber materials. The reinforcing potential is mainly attributed to two effects: (i) the formation of a physically bonded flexible filler network and (ii) strong polymer–filler couplings. Both of these effects arise from a high surface activity and the specific surface of the filler particles [3, 8, 28, 123]. For a deeper understanding of structure–property relationships of filled rubbers it is necessary to consider the aggregate morphology and surface structure of fillers more closely. The present chapter is devoted to several technological applications of fillers in rubbers. In particular, we demonstrate how the physics of rubber nano-composites facilitates the understanding of how new generations of fillers, like silica (instead of carbon black), boost tire technologies giving simultaneously improved performance in rolling resistance and wet grip behavior.

Since the introduction of the Energy ® tire by Michelin, precipitated silica has proved (through partial or total substitution of carbon black) to be the filler of choice for the manufacture of high-performance pneumatic passenger car tires. The main reason is an improvement in the final compromise between the main interrelated tire performance parameters: it gives a significant improvement in tire performance in regard to rolling resistance, wet grip, and stopping distance for cars equipped with anti-lock braking system (ABS) steering [124]. These improved characteristics mean that silica-filled tread compounds are also the best available materials for winter performance [125].