The study of the mechanical properties of rubber mixes containing different concentrations of manobond and KMR pro¬moters and their impact on the force of adhesion is very important since there is a relationship which relates the adhesion between NR and brass-coated steel cords and the square root of the rubber modulus [33] according to Eq. (2).
p = (4nrEAtt)^/2 = (2p£Aa)1/2