Dispersed Structure of Filler and Properties of Vulcanized Natural Rubber,Isoprene Rubber and Deproteinized Natural Rubber Filled with Carbon Black

Abstract

Relationship between morphology and mechanical properties of vulcanized rubber samples filled with carbon black was investigated. Samples of natural rubber (NR), isoprene rubber (IR) and deproteinized natural rubber (DPNR) were prepared using an internal mixer with a pair of 6-inch or 8-inch rolls. Dispersion of carbon black was evaluated by transmission electron microscopy and small-angle/ultra-small-angle X-ray scattering. Difference in tensile strength of the NR samples prepared by different pairs of the rolls was very small. This may be attributable to almost equal quality of the carbon black dispersion in the two kinds of NR samples. The tensile strength and volume resistivity of the IR sample were different from those of NR and DPNR samples, because of different quality of carbon black dispersion between IR and the other samples.