Method for controlling the mooney viscosity of compounded rubber formulations

Abstract

A method for obtaining a vulcanizable rubber formulation of controlled uniform viscosity properties containing synthetic rubber comprises the steps of determining the Mooney viscosity, MV.sub.a, of the synthetic rubber from which the formulation is to be prepared; determining the relaxation time, T.sub.80, of the synthetic rubber from which the formulation is to be prepared; calculating from MV.sub.a and T.sub.80 the Mooney viscosity, MV.sub.b, of the compounded rubber formulation; selecting synthetic rubber having MV.sub.a and T.sub.80 values within a predetermined range of values calculated to produce a compounded rubber formulation, the MV.sub.b of which is within a desired, preselected uniform range; and, compounding the selected synthetic rubber with carbon black and other conventional rubber compounding agents to produce the rubber formulation of MV.sub.b within the predetermined range of values. A method is also provided for predicting the Mooney viscosity MV.sub.b of a vulcanizable rubber stock containing styrene-butadiene rubber.

Dependencies are inferred from the claim text.