TECHNOLOGICAL ADDITIVES FOR OIL AND PETROL RESISTANCE RUBBERS BASED ON BUTADIENE-NITRILE CAOUTCHOUCS

The article investigated the influence of various technological additives (zincolet BB 222, lubstab-01 and MA-L22) on the technological properties of the rubber mixture, physical, mechanical and operational characteristics of rubber based on nitrile butadiene caoutchouc BNKS-40AMN. Basic rubber mixture studied included caoutchouc, BC-FF percadox, zinc monomethacrylate, maleide F, triallyl isocyanurate, acetonanil N, MGF-9 and THM-3 oligoester acrylates, carbon black P 514 and other ingredients. The rubber mixture was prepared on laboratory rolls LB 320 160/160 in two stages. At the first stage, BNKS-40AMN caoutchouc was mixed with ingredients and processing aids. As technological additives, zincolet BB 222, lubstab-01 and MAL22 were used In the second mixing step, BC-FF percadox and vulcanization coagents were introduced. For the obtained variants of the rubber mixture the vulcanization characteristics were studied on an MDR 3000 Basic rheometer at a temperature of 170 degrees C The rubber mixture prepared was vulcanized in a P-V-100-3RT-2-PCD type vulcanizing press at 150 degrees C for 40 min. Determination of elastic-strength and operational properties of rubber were carried out according to the standards existing for the rubber industry. The oil resistance of the vulcanizates was evaluated by changing their elastic strength after exposure to standard liquid SZHR-1 at a temperature of 125 degrees C, as well as by changing the mass of the samples after exposure to a mixture of isooctane with toluene at room temperature. It was found that the introduction of technological additives in the rubber compound improves the distribution of carbon black P 514 and powdered ingredients (zinc monomethacrylate, maleide F, triallyl isocyanurate, acetonanil H) in the caoutchouc matrix. Increased elastic strength indicators and their smallest changes after exposure to aggressive hydrocarbon media is characterized a rubber containing technological additive MA-L22. A comparison of technological, elastic-strength properties and resistance to aggressive media for rubbers containing butadiene-nitrile caoutchoucs BNKS-18AMN, BNKS-28AMN and BNKS-40AMN with optimal technological additives for them was done. It has been established that rubber containing BNKS-40AMN and technological additive MA-L22 is characterized by improved vulcanization properties, increased elastic strength indicators and their smallest changes after exposure to aggressive hydrocarbon media.