Abstract
The degree of carbon—black particle aggregation (transient structure) in conventional vulcanizates varies with the nature of the elastomers. This is revealed by the variation of (Gm′−G∞ƒ′), which is a measure of the transient structure. The relationship between Gm″ and (Gm′−G∞ƒ′) as well as that between strain work and normalized modulus show similarity to earlier work in which the polymer type was not varied. This suggests that carbon-black structural elements act as energy storage units and are of the same type in all these polymers. While the decrease of in-phase modulus is primarily caused by carbon-black particle units, tan δ reflects also the effect of the polymeric matrix.