Thermoplastic vulcanizates (TPVs) are special classes of thermoplastic elastomers, in which dynamic vulcanization of the rubber phase takes place during melt mixing with a semicrystalline thermoplastic matrix phase at elevated temperature. This review article focus on the different types of thermoplastic vulcanizates (TPVs) from various elastomer and thermoplastic blends that are suitable for the automotive applications purpose. A detailed study of the various TPVs based on polypropylene‐ethylene propylene diene rubber (PP‐EPDM) and polypropylene‐ethylene α‐olefin has been focused and their application in the automobile sector has been summarized. Most of the commercially available TPVs are PP‐EPDM based. Limited applications of that TPVs in high heat and oil resistant application purposes requires new generation of TPVs. High performance TPVs or super TPVs are new generation TPVs that exhibit high heat resistance as well as excellent oil resistance property suitable for automotive under‐the‐hood applications. Therefore TPVs based on XNBR‐PA12, HNBR‐PA12 and FKM‐PA6 system has also been explored in details in this study and the possibility of the use of those TPV system has been focused for the high temperature application purpose in the automobile sector where high and oil resistant application properties is the prime concern.

Silica is the rubber industry’s most essential and cost-effective reinforcing filler after carbon black. The silica reinforcement mechanism with a non-polar elastomer is complicated by the presence of polar functional groups on the silica surface. This polar nature of silica causes filler-to-filler interaction by forming hydrogen bonds. Therefore, sizeable non-dispersed silica clusters remain in a non-polar rubber matrix. To avoid these strong filler-filler interactions and improve rubber/silica compatibility, the silica surface needs to be modified. This can be done using a coupling agent which has functional groups capable of linking both the rubber and silica. It has been discovered that when silica/silane coupling agents are present, the critical properties like rolling resistance and wet grip in the magic triangle of tire tread balance out better than carbon black formulations, bringing the system closer to the green tire goal. In this review article, the efforts made by both the rubber formulation development and chemistry to fully exploit the potential of silica/silane reinforcement for automotive tires are retrospected. Highlights on how compounding ingredients, process technology, functionalized elastomer, novel silanes, and the variant of silicas can enhance the magic triangle and silica-silane reaction mechanism are provided. In addition, the kinetics of silanization and measurements for the degree of silanization is also highlighted. Future research directions in this area are also touched upon. Hopefully, this review can stimulate future silica/silane scientific and technology developments for both academic and industrial-oriented requirements.

Novel blends based on ethylene vinyl acetate/thermoplastic polyurethane (EVA/TPU) at different ratios were prepared via the melt blending technique. Scanning electron microscopy (SEM) studies revealed primarily a two phase morphology in which the minor TPU phase was dispersed in the major continuous EVA matrix. However in the 50/50 blend EVA and TPU appear as a co-continuous phase. The influence of blend ratio on the mechanical properties and hardness was investigated. An 80/20 EVA/TPU blend was observed to exhibit optimum tensile strength and elongation at break. Various models have been applied to predict the change in modulus with blend composition. The Veenstra B model was found the best to correlate the experimental modulus values. All the blends show a single T_g and a shift in T_g with change in blend composition was observed through differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), indicating technological compatibility. Thermogravimetric analysis (TGA) was performed to study the thermal stability of the EVA/TPU blends. Incorporation of TPU has also been found to improve the oil resistance properties of the blend system.