The role of filler networking in dynamic properties of filled rubber

No 48 presented at a meeting of the Rubber Division, American Society, Indianapolis, Indiana, May 5 – 8, 1998. Fillers when added to polymer systems are known to cause a considerable change in dynamic properties. For a given polymer and cure system, this paper will discuss the impact of the filler network, both its strength and architecture, on the dynamic modulus and hysteresis during dynamic strain. It was found that the filler network can substantially increase the effective volume of the filler due to rubber trapped in the agglomerates, leading to high elastic modulus. The amount of trapped rubber was estimated according to Van der Poel theory. During cyclic strain, while the stable filler network can reduce the hysteresis of the filled rubber, the breakdown and reformation of the filler network would cause an additional energy dissipation resulting in higher hysteresis.