Rheological Changes in the Processing of Rubber-Carbon Black Compounds

ABSTRACT: This work shows that the apparent viscosity and the effective relaxation time of rubber-carbon black compounds can be used to evaluate the quality of mixing along the mixing-milling-extrusion process. These rheo-metric functions allow one to estimate the degree of carbon black dispersion in relation to mechanical degradation of polymer chains along the production line. It is found that the Occluded Rubber Model is consistent with experimen-tal results, which are obtained through capillary rheometry. KEY WORDS: rubber-carbon black compounds, apparent viscosity, effective relaxation time, dispersion and degradation, quality of mixing, rheometry and swelling