Silica Obtained Via Pyrolysis of Waste Green Tyres: A Perspective Filler for Rubber Industry

A solid product (named SiO2D) is obtained as a result of subjecting the tread of "green" tyres to pyrolysis in the presence of water vapour. It has been found by FT-IR and EDX-RF spectroscopy that the product contains 30% of carbon, 65% of SiO2, 3% of ZnO and 2% of other components. The physicochemical and dynamic properties of the vulcanizates based on SBR filled with 75 phr SiO2D have been studied and compared to those of vulcanizates filled with conventional SiO2 as well as with such filled with a mixture of SiO2 and carbon black N 330 at a 2:1 ratio. Compositions with and without bis(3-triethoxysilylpropyl)disulfide have been also investigated. It has been established that there are not differences in the mechanical properties (modulus 300, tensile strength, abrasion, etc.) as well as the dynamic properties (heat build-up, tan delta, etc.) of the vulcanizates filled with SiO2D and of those filled with conventional SiO2 and carbon black at a 2:1 ratio.