SBR and BR Tread Performance as a Function of Carbon Black Properties

Abstract

All commercial tread grade carbon blacks, may be classified on the basis of electron microscope surface area and oil absorption. Similar industry wide grade classification on the basis of iodine number, tinting strength and oil absorption is considerably less reliable. However, among the blacks of individual carbon black suppliers, reasonably good classification of the tread grades is possible on the basis of these latter three carbon properties.

A General Correlation Between Treadwear and Carbon Black Properties

“…Furthermore, comparisons are usually made between blacks which are not greatly dissimilar, so that modest variations in m are obtained. Thus the very form of the experiment at once suggests expansion of Equation 1 into a Taylor series about some reference point 0 0 0 The values xl , X2, ... , Xj are properties of a selected reference carbon black,and the superscript zero on xi > j refers to fixed rubber recipe, mixing technique, degree of dispersion, tire construction, road test conditions, etc. With more compact notation defined by bxi = xi -x~, mo = f(xo)' fi(xo) = ðf(xo )/ðxl,and fii(xo ) == ð2 f(xo )/ðx[, etc., Equation 2 can be written as an abrasion resistance difference function which is general and complete for application within a given tire test.…”

“…In 1968 Micek, Lyon, and Hess [1] published a correlation of tire test results with electron microscopically estimated specific surface areas and vehicle demand (oil absorption). More recently, Hess and associates [2] attempted a similar correlation, based on a more limited volume of experimental data, with size and shape parameters derived entirely from electron micrographs by automatic image analysis.…”