Synergetic effect of epoxy resin and carboxylated nitrile rubber on tribological and mechanical properties of soft paper-based friction materials

In order to improve tribological and mechanical properties of rubber-based wet friction materials, five kinds of paper-based friction materials were prepared using the mixture of different ratios of epoxy resin (EP) and carboxylated nitrile butadiene rubber (XNBR) as a dual matrix. When the proportion of XNBR exceeds 40% in binder, the wear rate of paper-based friction materials begins to reduce, while the tensile strength, toughness and dynamic friction coefficient remain unchanged. In the end, the wear rate of the material for 80% XNBR in binder is reduced by 29% compared with material for 40%. This is attributed to ionic crosslinking network involved with divalent substances in fillers combining with the vulcanization effect of EP on XNBR.