Thermoplastic vulcanizates with an integration of good mechanical performance and excellent resistance to high temperature and oil based on HNBR/TPEE

Abstract

AbstractThermoplastic vulcanizates (TPVs), with a combination of excellent resilience of conventional elastomer and re‐processibility of thermoplastic, have been widely explored both in academia and industry in recent years. Herein, a new type of thermoplastic vulcanizates with good mechanical performance, excellent resistance to high temperature and oil has been successfully developed based on hydrogenated acrylonitrile butadiene rubber (HNBR) and thermoplastic polyester elastomer (TPEE) by the masterbatch procedure of dynamic vulcanization. The effect of composition ratio of rubber phase/plastic phase (R/P ratio) on the mechanical properties, rheological properties, micromorphology, thermal stability, high temperature‐ and oil‐ resistance of HNBR/TPEE TPV was systematically investigated. The results show that all HNBR/TPEE TPVs exhibit good tensile strength, low hardness, superior stretchability (≥880% elongation at break) and high elasticity (only 13% residual strain when stretched at 50% strain). Interestingly, with the increase in R/P ratio, the hardness of TPVs is decreased linearly and the elasticity increases. Besides, by combining the morphology study and rubber processing analyzer suggest that size of the dispersed rubber phase domains increases significantly as R/P ratio increases, which strengthen the rubber network, creating a better elasticity but reduces the rheological properties of TPVs. In addition, the thermogravimetric analysis shows that the thermal stability of TPV improved with the increase of R/P ratio. HNBR/TPEE TPV shows excellent high temperature‐ and oil‐ resistance after aging which is expected to be used in automotive applications.