Design of experiment was conducted to study the effect of alumina micro particles as a ceramic filler alone or along with two other ceramic fillers, boehmite and silicon carbide, on curing characteristics as well as the mechanical and thermo-physical properties of carbon black filled butyl rubber-based curing tire bladder composite. The effect of using silane coupling agent, X50S as well as increasing the polarity and stiffness of the polymer matrix by replacing the butyl rubber with

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... were also investigated. Examination of rheometry curing behavior of rubber compounds showed that alumina has a slight reduction effect on curing rate and maximum torque, which improves with the presence of the modifier, X50S. Boehmite showed a reducing effect on curing rate and maximum torque while the performance of silicon carbide was similar to that alumina. Also, the hardness of the composite increased with the presence of alumina similar to that SiC and decreased with the presence of boehmite and the resilience of the composites remained unchanged in the presence of ceramic fillers. A slight decrease in the tensile strength of the carbon black-filled butyl composites was observed in the presence of ceramic fillers both individually and as a blend. However, the study of the thermo-physical properties showed that the heat transfer coefficients of the butyl composites increase in the presence of alumina in the optimal amount of its use and are similar to the effects of SiC. However, it was not possible to further increase the heat transfer coefficients by further increasing the amount of alumina even in alloy conditions with SiC and boehmite, which was attributed to the reduction of filler dispersion in the polymer matrix that validated through optical dispergrader and FESEM/MAP analysis. The use of modifier along with alumina had only a small effect on improving the heat conductivity of butyl rubber. Also, changing the polarity and stiffness of the rubber matrix by completely replacing the butyl rubber with chlorobutyl did not show an effect on improving the thermal conductivity of the rubber in the presence of large amounts of alumina. It was concluded that alumina micro particles have the ability to be used in bladder rubber formula along with carbon black to improve the thermal conductivity of the rubber composite only to a limited extent.