Synthesis and Application of Silica Supported Calix[4]arene Derivative as a New Processing Aid Agent for Reducing Hysteresis of Tread Rubber Compounds Used in Low Rolling Resistance Tires

Rolling resistance is one of the most important properties of a tire which is highly dependent on the viscoelastic properties of its rubber compounds. There are a lot of ways to reduce this parameter both in construction improvement of the tire and changing in rubber compound formulation especially in tire tread formulation. Rubber scientists have been trying to introduce new processing aid agents beyond the traditional tire components for reducing the rolling resistance. In this study, a unique structure of silica-supported calix[4]arene (SS-CSC[4]A) has been synthesized and applied as a processing aid agent in tire tread formulation. Fourier-transform infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (1HNMR and 13CNMR), 29Si CP/MAS spectroscopy, thermal gravimetric analysis (TGA), elemental analysis, and acid-base titration were used to characterize its structure. Scanning Electron Microscopy (SEM) use to investigate the effect of prepared material on qualification of filler dispersion in the rubber matrix. The viscoelastic properties of the prepared rubber compound were measured by Dynamic Mechanical Thermal Analysis (DMTA) which showed the great decrease in rolling resistance of rubber compound based on SS-CSC[4]A as a processing aid agent. The mechanical and rheological properties of obtained tread rubber compound measured by tensometer and MDR rheometer showed no sensible changes in these properties.