Frictional Properties of Tread-Type Compounds on ICE

The laboratory test method described is capable of indicating with a fair degree of accuracy the tractive ability of a tire tread compound on ice. Coefficients of both dynamic and static friction are important in determining the resistance to slide of a tire. The base polymer in a tread compound is the principal factor affecting the coefficients of friction. Among compounds based on different polymers, the coefficients of friction on ice are not closely related to either the stiffness or hardness of the stock or to its hysteresis. The coefficients of friction of stocks based on a single polymer, however, are greatly influenced by the type and amount of softener and by the type and amount of black.