Estimation of resistance of engine rubber sealants to influence of mixed diesel fuel

The sorption-diffusion properties of rubbers in contact with fuels containing methyl esters of fatty acids derived from non-food raw materials have been studied. The hypothesis was advanced according to which there is a dependence of oil resistance of rubbers on their solubility parameter of butadiene-nitrile rubber. The properties of standard oil-resistant rubbers based on butadiene nitrile rubbers of SKN-18 and SKN-40 brands were compared with those of SKN-18-based rubber and Byprene 110 chloroprene-based rubber, to each of them 30% of the plasticized polyvinyl chloride was added. It was found that the contact with the fuel composition, which consists of 70% diesel fuel and 30% methyl esters of fatty acids made from technical sunflower oil, has the strongest destructive effect on all experimental samples of rubber except for rubber-based rubber of SKN-40 brand. It was determined that SKN-40-based rubber, which is characterized by the maximum solubility parameter, is the most stable in relation to fuel compositions containing methyl esters of fatty acids of various origins. Based on the analysis of experimental data, the recommendations were given for the use of SKN-40-based rubber for the manufacture of car engine seals within the global trend to increase the share of alternative components in diesel fuels.