Controlling the Performance of Filled Rubbers

The performance requirements for filled rubber greatly depend on the application (i.e., tires, engine mounts, belts, seismic isolation rubber, rubber rollers, etc.). Table I shows some examples. Thus, universal filled rubber, which possesses all the properties required for high performance products, is difficult to prepare, especially since some properties are antonymous. Additionally, the performance of filled rubber depends significantly on both the filler and filler aggregate structure. Consequently, high performance filled rubber is designed specifically for each product. Filled rubber is a composite material consisting of rubber and filler. In addition to selecting a suitable combination of rubber and filler, it is important to control the primary structure of the filler, the secondary structure of its aggregate, and its distribution. In particular, the appropriate processing conditions are indispensable to enhance the performance of filled rubber because the secondary structure of the aggregates and the distribution of the filler and/or its aggregates depend upon the structure of the filler and the processing conditions. Thus, precisely controlling the non-equilibrium structures of filled rubber governs performance. In this review article, methods to prepare high-performance filled rubber are described in terms of the relationship between the structure and properties of the filled rubber.