FIELD: rubber industry; other industries; compositions for production of the treads of the pneumatic tires and the methods of the compositions production.
SUBSTANCE: the invention is pertaining to the cross-linkable or cross-linked rubber composition characterized by the diminished hysteresis properties in the cross-linked state and by the improved manufacturability in the non-cross-linked state, to the method of its production, to the tread of the pneumatic tire and to the pneumatic tire. The composition contains the reinforcing filler consisting of the reinforcing inorganic filler, and, at least, one diene elastomer. The diene elastomer is produced in the form of the emulsion or the solution. The elastomer produced in the form of the solution has the molar contents of the conjugated dienes links exceeding 30 % and is produced at the following stages. At the first stage the initial diene elastomer is subjected to the reaction of the hydroaluminization or carboaluminization along the chain in the inert hydrocarbon solvent by addition to it of the aluminum-containing agent. At the second stage the produced product is added with, at least, one electron-seeking reagent intended for interaction with the indicated aluminum-containing agent. At the third stage they stop the process of the reaction of the second stage and extract the elastomer containing the functional groups of the carboxylic acid along the chain. The reinforcing inorganic filler is selected from the group including the highly dispersive silica, argil, Al(OH)3. The method of production of the composition includes the first stage of the thermomechanical treatment of the above-indicated elastomer and the reinforcing inorganic filler at the maximal temperature from 130°С up to 200°С, and the second stage of the mechanical working at the temperature smaller than the temperature of realization of the first stage with introduction of the cross-linking system. The diene elastomer received in the emulsion contains the functional groups of the carboxylic acid along the chain and is produced using the emulsifying solution by the method of the copolymerization by the following way. To the indicated emulsifying solution of the monomer or the monomers of the conjugated diene (the conjugated dienes) possibly with one or the several vinyl aromatic compounds add the comonomer consisting of unsaturated aliphatic carboxylic acid taken from the group consisting of the acrylic acid, the methacrylic acid, the maleinic acid, the fumaric acid. The method of production of the above-indicated composition includes the first stage of the thermomechanical working of an above-stated elastomer and the reinforcing inorganic filler, except for the system of cross-linkage at the maximal temperature from 130°С up to 200°С, and the second stage of the mechanical working at the temperature smaller than the temperature of realization of the indicated first stage with addition of the cross-linkage system. In one of the versions of the method the composition includes two phases of the first stage: At the first phase of thermomechanical working they introduce completely the whole amount of the monoxide for activation of the subsequent cross-linkage and intermix all the components, at the second phase they introduce the antioxidant and admix with components of the first phase. In the other version at the first phase of the first stage they introduce zinc monoxide and magnesium monoxide. The invention allows to produce the composition with the improved hysteresis properties in the cross-linking state and the pneumatic tire containing the tread produced from the composition with the reduced resistance to the rolling movement.
EFFECT: the invention ensures production of the composition with the improved hysteresis properties in the cross-linking state and the pneumatic tire containing the tread produced from the composition with the reduced resistance to the rolling movement.
20 cl, 10 tbl, 9 ex
