Abstracts

№6, 2015

Effect of Molecular Weight Distribution of Solution Styrene-Butadiene Rubber on the Properties of Rubber Mixtures and Vulcanizates on its Base – Borisenko V.N., Akhmetov I.G., Galimov R.R., Sakhabutdinov A.G. (P. 4)

The aim of this study was to investigate the influence of molecular mass characteristics of solution styrene-butadiene rubber on the properties of rubber compounds and vulcanizates on its base. Preparation of rubber samples was performed on pilot plant simulating all the stages of industrial production by continuous process in hexane solvent. N-butyllithium modified by the mixture of alkoxides of alkali and alkaline earth metals was used as an initiator. A series of copolymers with relatively constant Mooney viscosity ~ 65 conv. u., 22 % styrene content and a high proportion of vinyl structures ~ 65% were prepared for test. The main difference consists in various values of SSBR polydispersity from 1.8 to 3.2 caused by decrease in number-average molecular weight and increase in weight-average molecular weight. Significant impact of molecular-mass characteristics of SSBR on the change of Mooney stress relaxation of the samples is shown. The increase of rubber polydispersity results in reducing of viscosity of rubber compounds. Strength properties of vulcanizates are on the same level; however tgδ at 60°С of vulcanized rubber increase with polydispersity. So SSBR of minimum (in the studied range) polydispersity is of the best dynamic properties, and can provide the tire rubbers of the best rolling resistance.

Key words: solution styrene-butadiene rubber, SSBR, polydispersity, tgδ, rolling resistance

Effect of the Water to Hydrocarbon Phases Ratio on Butyl Rubber Bromination Process – Orlov Yu. N., Abramova N.V., Fialko A.V. (P. 8)

The results of studying the effect of the water to hydrocarbon phases ratio on the kinetics of butyl rubber bromination by aqueous solution of bromine are presented. The possibility of bromination of an aqueous dispersion of butyl rubber crumb in the absence of hydrocarbon solvent is examined. It is demonstrated that the effective constant of butyl rubber's bromination reaction rate in a hydrocarbon solution is directly proportional to the amount of water put in reacting mass. Butyl rubber's bromination in water dispersion generates mainly products of conjugate addition via double linkage followed by rearrangement.

Key words: butyl rubber, an aqueous solution of bromine, the water to hydrocarbon phases ratio, an aqueous dispersion of butyl rubber

The Investigation of the Influence of Silane Modified Mineral Shungite of Different Dispersion Degree on the Properties of Elastomer Composites – Kornev Yu.V., Boiko О.V., Gus’kov D.V., Semenov N.A., Valiev Kh. Kh. (P. 12)

Elastomer composites are one of the most prospective constructional materials. At designing and manufacturing of elastomer composite materials, constructions and goods, considerable attention is paid on ecology, economical and energy efficiency. So the application of mineral fillers in elastomer composites is of high importance. The coupling agents provide the possibility to improve the properties of elastomer composites of mineral fillers. Effect of concentration of organosilane coupling agent TESPT on mechanical properties of elastomer composites filled with mineral shungite of different dispersity is under investigation. Crystallographic structure of nanodispersed shungite was determined by X-ray method. Surface structure of composites was studied by ASM, their processing and mechanical properties – by means of different modern instruments. Increase of modulus, stress at elongation, hardness and decrease of tg δ as well as improve of filler distribution for elastomer composites filled with nanodispersed mineral shungite with the addition of coupling agent is noted. Increase of TESPT content and shungite dispersity enhances these effects. Effect of TESPT in some cases is in contrast with its effect in compounds filled with silica.

Key words: elastomer nanocomposites, SBR, nanodispersed shungite, coupling agents, organosilane TESPT, X-ray, ASM, SEM, filler distribution, processing properties, mechanical properties, tg δ, Payne effect

Stabilization of Rubber SKI-3 by Oxopropylidene Aromatic Amines – Lin’kova T.S., Zemskii D.N., Kurlyand S.K., Zemskii N.I. (P. 18)

Oxopropylidene aromatic amines were synthesized and used as stabilizers of rubber SKI-3. Physico-chemical and toxicological properties of synthesized products were determined. The structure of the experimental compounds was confirmed by NMR-spectroscopy and chromato-mass-spectrometry. The value of the index of harmless concentrations of experimental compounds of β-oxopropylidenes is increased in the row: aniline, toluidine, xylidine. It is directly associated with reduced ability of compounds to dissolve in water and to form the stable emulsions. Comparison of the stabilizing ability of the experimental and industrial stabilizers was carried out in two stages: determining the viscous and heat properties of rubber with stabilizers itself and determining physical and mechanical properties of tire rubber with stabilizers. Three of experimental stabilizers showed the best results. One of them (T-1) is the more affordable. Increase of the dosage of this stabilizer reduces the speed and depth of the destructive processes in an extruder. The mixture of Novanox-PFDA and stabilizer T-1 shows synergies of their stabilizing abilities. The investigated stabilizers is equivalent to, and in some cases exceed industrial samples of antioxidants, which eliminates import counterparts from the domestic market and thereby solve the problem of import substitution in this area, because the stabilizers are made entirely from domestic raw materials.

Keywords: hydroxypropyl aromatic amines, stabilizers, antioxidants, rubber stabilization, SKI-3

Study of Tribological and Adhesive Properties of Frost-Resistant Rubber – Morozov A.V., Muraveva T.I., Petrova N.N., Portnyagina V.V., Ammosova V.N., Zagorskii D.L. (P. 22)

Tribological, viscoelastic and adhesive properties of frost-resistant rubber, which composition is based on propyleneoxide rubber and butadiene acrylonitrile rubber have been studied. Tribological tests were performed by “rubber ring – steel disk” contact type at -25 C to 22° C, at 1 to 100 m/s sliding velocity and at 0,1 to 0,3 MPa normal pressures. Reduction of friction properties of rubber was obtained by adding friction modifiers: carbon black and ultra fine PTFE (uPTFE) powder. The friction coefficient of the propyleneoxide rubber , filled with carbon black, was 3-5 times lower than friction coefficient of industrial rubber B-14 based on butadiene acrylonitrile rubber BNKS-18 in the all studied temperature range. Tribotechnical characteristics were improved by adding to rubber the small amounts of ultra fine PTFE, the low-temperature properties practically didn’t changed. Friction coefficient of propyleneoxide rubber filled with ultra fine PTFE or carbon black were substantially constant in temperature range from -15 °C to -25° C. This allows us to assume the possibility of their stable functioning as sealing in sealing arrangements under dynamic stresses and cyclic deformations.

Key words: propyleneoxide rubber, BNK, uPTFE, carbon black, sliding friction, coefficient of friction, low-temperature properties, arctic materials

Directions of Prolongation of Service Life of Rubber Reinforced Tracks Beinenson V.D., Fedotkin R.S., Kryuchkov V.A., Alendeev E.M., Kupryunin D.G. (P. 28)

Due to well-known advantages of caterpillar mover over wheel mover, rubber reinforced tracks are finding today a wide application on foreign vehicles – agricultural, industrial and military caterpillar vehicles etc. The work of development of construction and processing of rubber reinforced tracks as well as organization of their serial production in Russian Federation is carried out. The main cause restricted tracks life cycle is cracks of fatigue origin in flexing zone of tread section. Combined action of fatigue and abrasive wear results in broken of tracks reinforcing layer. Conditions of repair of tracks by fixing of cracks are under consideration. Analysis of stress concentration on cracks boundary under opening and flexing in dependence of crack shape and groove angle with the use of finite element method is presented. Model specimens as fragment of tracks are in use. The model rubber reinforced tracks are tested. The optimal conditions are chosen providing increase of service life in 85%. Composition for repair is recommended. Due to positive benchmark test results, the restoring technology of rubber reinforced tracks can be used for restoring full dimension rubber reinforced tracks in service conditions.

Key words: rubber reinforced tracks, cracks of rubber layer, fatigue, stress concentration, FEM, repair of tracks, composition for repair

Formation of Structure of Composite Materials Based on Latex Impregnated Non-Woven Needle-Punched Webs – Dedov A.V.,

Garnova N.Yu. (P. 32)

The method is proposed for evaluation of the process of formation of structure of composite materials based on needle-punched non-woven materials from polyester fibers of 20 microns diameter, impregnated with latex (DVHB-70). The web structure and the degree of impregnation were varied. The structure of the web provides the possibility of complete filling of the pores by latex as well as the possibility to vary the dimensions of the composite materials during drying processes, such as shrinkage or the preservation of volume. The dependence of the density of the composite material on the degree of impregnation provides the parameter reflecting the conditions of formation of structure of material of varying degrees of impregnation. The dependence of structure formation of the composite material on the sheet structure is established. It effects the mobility of the fibers, and consequently on the fabric shrinkage during the drying process. The industrial process of impregnation of the webs and the impact of individual stages of the processing on structure formation of composite materials is under consideration.

Key words: composite material, latex, non-woven needle-punched fabric, impregnation, structure, drying process, shrinkage

Directions of Processing of Sub-Standard General-Purpose Synthetic Rubber – Novozhilova A.I., Zemskii D.N., Kurlyand S.K. (P. 36)

Imperfection of methods of synthesis of rubbers led to accumulation of significant amounts of sub-standard high-molecular materials on grounds of burial. The purpose of this work was the consideration of some directions on processing of sub-standard polymers. The structure and molecular characteristics of polymeric components of samples are defined. Possibility of the use of the processed sub-standard rubbers in irresponsible rubber products is shown, but the vulcanizates containing these rubbers possess unsatisfactory physical and mechanical properties, have porous structure and a pronounced smell of monomer. The second direction of the use of sub-standard rubbers is their addition to road bitumens. It is shown that low-temperature and elastic properties of bitumens improve, however an essential lack of the received composites is inadmissible low temperature of flash. The most perspective direction of processing of this sort of waste is process of hydrocracking. As a result of hydrocracking the hydrocarbon fractions are formed which may be in use as high-quality components of motor fuels. Laboratory-scale plant of thermal cracking of initial samples in the presence of hydrogen is developed, its schema is presented. This way of processing of sub-standard rubbers allows not only receiving high-quality components of motor fuel, but also considerably improving an ecological situation near burial grounds.

Key words: processing of sub-standard rubbers, high-octane additives, cracking of rubbers

Calculation of Interrelated Processes of Chemical Transformations and Heat Exchange with Account of Hydrodynamics for the Process of Synthesis of Butyl Rubber – Tereshchenko K.A. Ulitin N.V. (P. 40)

The mathematical description of macrokinetics of process of butyl rubber synthesis have been developed (cationic copolymerization of isobutylene with isoprene, on the AlCl3 catalyst among CH3Cl, synthesis temperature higher than 173 K), which takes into account the interrelated processes of chemical conversion and heat transfer, and also hydrodynamics of reactor equipped with a mixer. It has been found that with the increase of catalyst concentration (from 4.10 to 1 mol / l) and reduction of the rotation rate of the mixer (from 4 to 0.5 rev. / sec.) the number average (from 1200 to 201 000) and weight average (from 39 400 to 406 000) molecular weight of butyl rubber will decrease at the slight change of its polydispersity index (close to 2).

Key words: butyl rubber, computational fluid dynamics, isobutylene, isoprene, cationic copolymerization, heat exchange.

Materials of Extra-High Level of Low Temperature Properties – Fomina L.G., Chelmodeev A.D., Chebotarev Yu.M., Lvova G.N. (P. 44)

Composition of technical rubber based on noncrystallizable dimethyldiethylmethylvinyl silicone rubber SKTEM-1 of glass transition temperature Tg = 137 – 138 К has been developed. Optimal type and content of vulcanizing agents, thermostabilizers, and fillers as well as vulcanizing regime were chosen. Low temperature recovery of developed rubber is: 0,70 at 213 К, 0,48 at 173 К, 0,38 at 153 К and 0,26 at 143 К. Strength of developed rubber is nearly 10,0 МПа, storage life of row rubber compound was 4 month, larger than for row rubbers based on other silicone rubbers. O-rings as seals from developed rubber retain their service ability up to 143 К. According data of NPO “Kriogenmash” this rubber is of elongation 9% at liquid nitrogen temperature.

Key words: dimethyldiethylmethylvinyl silicone rubber, extra-high level of low temperature properties, recovery, strength properties, storage life of row rubber, O-rings, seals

International Rubber Conference IRC-2015 – Reznichenko D.S., Morozov Yu.L. (P. 46)

Review of papers presented at the International Rubber Conference IRC-2014 (Nyurenberg, Germany, 29.06. – 02.07.15)

Key words: rubber, fillers, nanocomposites, ingredients, processing, tires, rubber goods

International Exhibition “Chemistry-2015” – 50 Years on Russian Exhibition Market

Post-release on 18 International Exhibition “Chemistry-2015” (Moscow, Expocenter, 27 – 30.10.15.) (P 52)

Key words: exhibition, chemical industry, row materials for chemical industry, chemical production, “green chemistry”, analytical and laboratory equipment, chemical mechanical engineering, row materials for rubbers and other polymers

Strategy of the Progression of Chemical Industry – the Main Subject Matter of Moscow Chemical Forum (P 58)

Post-release on the III Moscow International Chemical Forum organized by Russian Chemical Union at Exhibition “Chemistry-2015”

Key words: chemical industry, mineral fertilizers, synthetic fibers, state support, investments

Marketing Problems of Rubber Industry (Notes of Our Correspondent According Post-Release on the Conference by Company INVENTRA) – Kanauzova A.A. (P. 60)

Review of papers presented at the Conference “Rubbers, Tires and RTA” organized by INVENTRA, CREON group (16.10.15., Moscow)

Key words: rubbers, tires, rubber technical articles, marketing, export, import

Up the Staire Down (P. 64)

From the Post-release on the 7th International Conference “Polymers in automobile manufacture 2015”, organized by INVENTRA, CREON group (20.05.15., Moscow)

Key words: automobile industry, auto components, polymer compounds, polyurethanes, polyolefines, localization, stability of quality of row materials and goods