Study on Aging Mechanism of HNBR Vulcanizate in High Temperature Oil and Water Environment

Rubber is a crucial sealing material in the petroleum industry. Due to increasingly stringent industrial development, safety performance requirements are becoming extremely high, resulting in higher oil resistance requirements for rubber. HNBR exhibits good heat resistance, high tensile strength, tear strength, and excellent wear resistance. However, a certain degree of aging will also occur in the actual service process, which will affect the service life of rubber. In order to explore the factors affecting the aging behavior of HNBR vulcanizates in an oil–water environment at 150 °C, HNBR vulcanizates were aged in an independent environment. IR (Infrared) spectroscopy analysis (FTIR), crosslinking density analysis, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM) testing were used to characterize the microstructural and morphological changes in HNBR vulcanizates before and after aging. The aging mechanism of HNBR vulcanizates in different environments was obtained. Since factors such as rubber fillers remained constant throughout the experimental process, the influence of formulation variables on aging was disregarded.