The dynamic properties of carbon black loaded natural rubber vulcanizates. Part II

Abstract

Abstract The dynamic shear modulus at very high strains, ( G ∞ ), of carbon black filler loaded vulcanizates is regarded as due to the product of two factors: ( a ) a hydrodynamic interaction due to filler particles, and ( b ) a second factor for which evidence is given suggesting that it arises from a few strong linkages which are known to link filler particles to the matrix. Experimentally a measure of ( a ) has been obtained from model vulcanizates using glass spheres as the filler, and of ( b ) from equilibrium swelling measurements on rubber vulcanizates containing carbon black. Quantitatively, the difference between the shear modulus of the pure gum vulcanizate, G pure gum , and G ∞ can be explained by these measurements.