An experimental study of tear strength of styrene-butadiene rubber (SBR) filled with various concentrations of HAF carbon black has been carried out. A trouser-leg tear test was used to determine tear strength. We focus attention with tearing initiation strength and the associated elongation ratio. The effects of temperature and tearing speed on the initiation of the tear properties were investigated. The values of tearing initiation strength obtained at every temperature and every tearing speeds for a kind of samples were found to be approximately proportional to the associated elongation ratios. As results of trying superposition for tear strength at initiation of rubber, time-temperature superposition principle of tearing initiation properties was found to be effective.
