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Silicone rubber/ethylene‐vinyl acetate copolymer/magnesium sulfate whisker composites containing ethylene‐acrylic acid copolymer (MS/SR/EVM/EAA) as a compatibilizer were successfully prepared. Moreover, the magnesium sulfate whisker surface was modified with 3 wt% of silane coupling agent (KH570), resulting in composites including (unmodified magnesium sulfate whisker) uMS/SR/EVM, (modified magnesium sulfate whisker) mMS/SR/EVM, and mMS/SR/EVM/EAA were compared. The values of thermal decomposition activation energy (Ea) calculated by the two different methods (Kissinger and Friedman methods) show that the composites filled with 5 and 20 phr whiskers have lower values of activation energy (Ea) than the SR/EVM blend. The tensile strength of composites with a 5 phr modified whisker is 14.5 MPa, which is higher than that of the SR/EVM blend and uMS5/SR/EVM composite. The tear strength of the composite with 20 phr mMS is 51.6 kN m−1, much higher than that of the composite with 20 phr uMS and SR/EVM blend. The mechanical properties were also investigated after thermal aging of the composites at 85°C for 48 h. The thermal conductivity of the composites with high filler loading was studied.

The filler-rubber interaction and filler dispersion in natural rubber (NR) composites are important factors in determining mechanical properties. Herein, Molybdenum disulfide (MoS 2 ) and Al 2 O 3 -coated MoS 2 nanospheres are incorporated in NR/carbon black composites. The effects of MoS 2 and Al 2 O 3 -coated MoS 2 on the morphology, thermal and mechanical properties of the NR composites are investigated. The morphology analysis indicates that Al 2 O 3 -coated MoS 2 could greatly improve the dispersion of carbon black in NR composites. MoS 2 filler and carbon black show a synergetic effect on improving the properties of NR composites, leading to high abrasion resistance, tensile strength, elongation at break and expected dynamic mechanical properties. The thermal conductivity of NR composites increases with increasing the content of MoS 2 and Al 2 O 3 -coated MoS 2 . The thermal stability of the NR composites is also effectively improved by filling MoS 2 and Al 2 O 3 -coated MoS 2 . Furthermore, a small amount of Al 2 O 3 -coated MoS 2 significantly improves the abrasion resistance, wet grip and decreases rolling resistance of the composites. Al 2 O 3 -coated MoS 2 exhibits its potential application in green tires with good performance.