Research changes in the properties of butadiene-nitrile rubber under various aging conditions

This article represents the results of a study of changes in the properties of vulcanizates based on BNR-18 butadiene-nitrile rubber containing as stabilizers the experimental spatially hindered phenols Stafen, CO3, CO4, and industrial antioxidant 6PPD, after accelerated aging (100 degrees C 96 h) and aging under full-scale exposure in extreme climatic conditions of the Republic of Sakha (Yakutia) during 2 years. In winter, the air temperature reached-48 degrees C, in summer-+36.1 degrees C. It is shown that the experimental sterically hindered phenols more effectively under natural exposure conditions. They are characterized by the most stability in terms of strength throughout the entire exposure period. Under conditions of accelerated aging, the vulcanizate containing the industrial antioxidant 6PPD is characterized by the greatest stability of physical and mechanical properties. According to the viscoelastic characteristics obtained in the dynamic loading mode, the contribution of the presented stabilizers in maintaining resistance to temperature and deformation effects compared with unstabilized rubber is confirmed.