Hydrogenated butadiene-nitrile rubber elastomers: research of functional properties

The subject of the study were rubbers based on partially and fully hydrogenated nitrile-butadiene rubbers (HNBR) Therban АТ 5065 VP and Therban АТ 5005 VP, taken individually and in the ratios 80:20, 70:30, 60:40, 50:50 accordingly. The purpose of the work was to study the functional properties of rubbers based on HNBR of various degrees of unsaturation using modern methods of analysis. The degree of dispersion of the filler and the thermodynamic compatibility of polymer components in rubbers based on Therban АТ 5065 VP and Therban АТ 5005 VP mixtures are appreciated. Glass transition and decomposition temperatures, elastic modulus and mechanical loss tangent of HNBR-based and their combined compositions were identified. The microrelief of the surface of rubber samples based on HNBR, taken in different ratios, was investigated.

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.

COPPER-CONTAINING NANOCOMPOSITES ON THE BASIS OF ISOTACTIC POLYPROPYLENE AND BUTADIENE-NITRILE RUBBER

The influence of additives of nanofillers containing nanoparticles of copper oxides stabilized by a polymer matrix of maleinized high-pressure polyethylene obtained by the mechano-chemical method on the structure and properties features of metal-containing nanocomposites based on isotactic polypropylene and butadiene-nitrile rubber by x-ray phase and differential thermal analyses is studied. The improvement of strength, deformation and rheological parameters, as well as thermal-oxidative stability of the obtained nanocomposites was revealed, that is probably due to the synergistic effect of interaction of copper-containing nanoparticles with maleic groups of maleinated high-pressure polyethylene. It is shown that nanocomposites based on isotactic polypropylene and butadiene-nitrile rubber can be processed both by pressing method and by injection molding and extrusion methods that expands the scope of its application

Mechanism and kinetic regularities of crystallization of nanocomposites based on bentonite and polymer mixtures of random polypropylene with butadiene nitrile rubber

The paper presents the results of a study of the dilatometric properties of thermoplastic elastomer nanocomposites based on mixtures of random polypropylene, nitrile butadiene rubber, a compatibilizer - copolymer of polypropylene with maleic anhydride. Nanosized bentonite particles were used as a filler. The concentration of bentonite nanoparticles was varied in the range of 1.0-20 wt %. The values of the free and occupied specific volumes of nanocomposites were determined depending on the temperature and concentration of bentonite. The mechanism and kinetic regularities of the crystallization process of nanocomposites are established.

Research changes in the properties of butadiene-nitrile rubber under various aging conditions

This article represents the results of a study of changes in the properties of vulcanizates based on BNR-18 butadiene-nitrile rubber containing as stabilizers the experimental spatially hindered phenols Stafen, CO3, CO4, and industrial antioxidant 6PPD, after accelerated aging (100°C 96 h) and aging under full-scale exposure in extreme climatic conditions of the Republic of Sakha (Yakutia) during 2 years. In winter, the air temperature reached—48°C, in summer—+36.1°C. It is shown that the experimental sterically hindered phenols more effectively under natural exposure conditions. They are characterized by the most stability in terms of strength throughout the entire exposure period. Under conditions of accelerated aging, the vulcanizate containing the industrial antioxidant 6PPD is characterized by the greatest stability of physical and mechanical properties. According to the viscoelastic characteristics obtained in the dynamic loading mode, the contribution of the presented stabilizers in maintaining resistance to temperature and deformation effects compared with unstabilized rubber is confirmed.

INFLUENCE OF ANYLES D, L- CAMPHORA ON THERMAL OXIDATING STABILITY OF BUTADIENE RUBBER BASED ELASTOMER

The influence of aniles DL-camphor as N-[(1RS)-camphane-2-ylidene]-2-methylaniline, N-[(1RS)-camphane-2-ylidene]-2-ethylaniline and N-[(1RS)-camphane-2-ylidene]aniline on vulcanization and resistance of butadiene nitrile rubber based elastomers to thermal oxidative aging was studied for the first time. The prospects of using aniles DL-camphor as anti-aging agents have been established. The best effect is achieved when using N-[(1RS)-camphane-2-ylidene]-2-methylaniline in combination with an effective vulcanisation system including sulfur donors tetramethylthiuram disulfide, 4,4'-dithiodimorpholine, and N-cyclohexylbenzothiazole-2-sulphenamide.

RHEOLOGICAL PROPERTIES OF MIXTURES OF RANDOM POLYPROPYLENE WITH BUTADIENE-NITRILE RUBBER AND VULCANIZATES BASED ON THEM

The paper presents the results of studying the effects of butadiene-nitrile rubber concentration and temperature on the flow curves of the random polypropylene-based polymer blends. To improve the technological compatibility of polymer blends, a graft(ed) copolymer of polypropylene with maleic anhydride was used as a compatibilizer. Melt viscosity as a function of temperature and shear rate is shown, and the activation energy of a viscous flow has been defined. A generalized temperature-invariant characteristic of the viscosity properties of polymer blends has been plotted. This makes it possible to predict the value of their effective viscosity at high shear rates, close to real processing conditions

Influence of the Content and Nature of the Plasticizer on the Properties of Butadiene-Nitrile Rubber

In this article investigates the effect of the content of plasticizers on the properties of rubbers based on rubber BNKS-18 AMN. The traditional, widely used dioctyl phthalate (DOP), as well as the more modern, environmentally friendly dioctyl terephthalate (DOTP), were used as plasticizers. It has been established that the introduction of plasticizers contributes to the production of rubbers with an improved complex of operational properties, such as elasticity, frost resistance, resistance to the corrosive media SZhR-3. At the same time, according to the research results, it was revealed that the introduction of plasticizers in an amount of 20 phr leads to the most noticeable improvement in these properties. In terms of physicomechanical and low temperature properties, the samples containing DOTP significantly exceed those of the samples containing DOP. Thus, our data showed that the use of DOTP is promising as an alternative to the widely used DOP