ABSTRACT
This chapter summarizes work on the structure of precipitated silica used in the reinforcement of elastomers. Silica has a unique morphology, consisting of multiple structural levels that can be controlled through processing. The ability to control and characterize the multiple structures of precipitated silica is an example of morphological engineering for reinforcement applications. The structure of several different precipitated silica powders is shown the mechanical properties of elastomers reinforced with the silica particles. A series of precipitated silica samples were studied using small-angle scattering and elastomer compounds were made to test the reinforcing effects of the silica. The structure–property relationships developed for filled elastomers have evolved into the following major areas: Filler structure, hydrodynamic reinforcement, and interactions between fillers and elastomers. In the rubber industry there is specific interest in understanding how fillers reinforce elastomers. There is a wealth of knowledge regarding the synthesis of these fillers, the mechanisms that govern the synthesis, and the characterization of resulting filler structures.
