Effect of the same amount of precipitated silica nanofiller on the processing and dynamic properties of natural rubber (NR), synthetic polyisoprene (IR), polybutadiene (BR) and styrene-butadiene rubber (SBR) was investigated. The silica surfaces were pre-treated with bis(3-triethoxysilylpropyl) tetrasulfane (TESPT) to chemically bond silica to rubber. The rubbers were primarily cured by using sulfur in TESPT and adding accelerator and activator, which helped to form sulfur chemical bonds between the rubber and filler. The silica particles were fully dispersed in the rubber matrix.The Mooney viscosity, cure and dynamic properties of the filled rubbers including tan , loss modulus ( ) and storage modulus ( ) were measured as a function of temperature from -130 to 100oC, oscillation amplitude from 15 to 1000 m, and test frequency from 1 to 100 Hz. It emerged that the dynamic properties of the rubbers were significantly affected by the test parameters. For example, at 1 Hz frequency and 256 m oscillation amplitude the BR rubber had the largest and IR rubber the lowest tan  values as a function of test temperature. These differences were attributed to the bounded rubber (in-rubber structure) produced by chemical bonding between the silica surface and the rubber chains via TESPT coupling agent. The SBR rubber had the lowest bound rubber content compared with the remaining rubbers. Moreover, differences in glass transition temperature also contributed to the varying dynamic behavior of the rubbers. The results have major implications for the use of this filler in tire tread rubber compounds.

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