INFLUENCE OF HINDERED PHENOLIC STABILIZERS ON THE CLIMATIC STABILITY OF RUBBERS BASED ON EPICHLOROHYDRIN CAOUTCHOUC

Abstract

Hindered phenolic stabilizers are effective inhibitors of oxidation processes of various materials, including elastomeric ones, due to their SHAPE \\* MERGEFORMAT unique chemical structure. The advantages of phenolic stabilizers, especially the hindered ones, in rubber production are low toxicity, non-volatility, and the ability not to stain vulcanizates. The stabilizing efficiency of these stabilizers in real climatic conditions has been studied insufficiently. In this work, for the first time, a study was conducted on the influence of hindered phenolic stabilizers СО-3, СО-4 and Stafen of pilot production of N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry (NIOCH SB RAS) on the physical-mechanical properties of rubbers based on epichlorohydrin caoutchouc (ECHС) of Hydrin T6000 brand under the influence of the extreme cold climate of the Republic of Sakha (Yakutia). The amine stabilizer 6PPD (China), widely used in the rubber industry, was selected to compare the properties. Stabilizers were added to the rubber mixture in the amount of 1 wt. p. per 100 wt. p. of caoutchouc. Rubber samples were exposed to the atmospheric conditions for two years at the climatic testing ground of the Institute of Oil and Gas Problems of SB RAS (IPNG SB RAS), as well as the environment of the oil from the Talakan field and I-50A industrial oil in a room where the ambient temper ature varied from minus 3 °C to 1 °C in January and from 17 °C to 20 °C in July. It has been found that hindered phenolic stabilizers of the NIOCH SB RAS pilot production are superior to the 6PPD industrially produced amine stabilizer in terms of the effectiveness of stabilizing properties of rubbers. Rubber containing Stafen stabilizer demonstrated the best retention of properties in the environment of ambient air and I-50A industrial oil regardless of the exposure duration. In the oil environment, rubbers containing СО-4 and Stafen stabilizers showed the best stability of properties throughout the exposure.