Epichlorohydrin Rubber Research Articles

The overall performance of graphene oxide-reinforced epichlorohydrin rubber nanocomposites

The overall performance of graphene oxide-reinforced epichlorohydrin rubber nanocomposites

Choice of Accelerators of the Vulcanization Group for Rubbers Based on Epichlorohydrin Rubber

Choice of Accelerators of the Vulcanization Group for Rubbers Based on Epichlorohydrin Rubber

Investigation of the low‐temperature properties and oil resistance of peroxide‐cured epichlorohydrin rubber and nitrile butadiene rubber blends

Investigation of the low‐temperature properties and oil resistance of peroxide‐cured epichlorohydrin rubber and nitrile butadiene rubber blends

Preparation and characterization of hydrophilic and water‐swellable elastomeric nanocomposites

AbstractHighly polar and hydrophilic polymers; ethylene‐vinyl acetate (EVA), epichlorohydrin rubber (GECO), and polyethylene oxide (PEO) reinforced with fillers (carbon black (CB) and/or Silica) were used to prepare water‐swellable rubber nanocomposites. The study showed that although the high content of the GECO delayed vulcanization of the corresponding compounds, the sample filled with desired ratio of GECO/PEO/EVA or GPE, cross‐linked with peroxide exhibited the highest swelling performance of ⁓150%. The samples exhibited good re‐usability performance in the re‐swollen test, after drying. At prolonged water swelling, the tensile strength dropped drastically for compounds with high content of the GPE, due to weak filler‐matrix interactions. On the other hand, the incorporated GPE also increased the rebound resilience (%) property which is a key requirement in green tire fabrication. For example; peroxide cured sample coded SR3 (GPE‐15 phr CB) obtained ⁓30% resilience in non‐swollen state and ⁓53.5% after 1440 min of water‐swelling, which represents a dramatic development of over ⁓78% in rebound resilience. Thus, a proper balance between the GPE content, curing agent and the reinforcements may guarantee high water‐swelling performance and mechanical properties integrity for multifunctional applications such as wound healing, structural works, water collection from oil spillages, and for the development of water‐based sensors.

Выбор ускорителей вулканизации для резин на основе эпихлоргидринового каучука

The effect of vulcanization accelerators on the structure and properties of rubbers based on Hydrin T6000 epichlorohydrin rubber has been studied. Mercaptobenzthiazole (MBT) in the amount of 1.5 pts.wt., tetramethylthiuram disulfide (TMTD) — 0.5 – 1.5 pst.wt. were used as accelerators and N,N’-diphenylguanidine (DPG) — 0.5 – 1.5 pst.wt., which represent a triple system of accelerators. The choice of accelerators is based on the possibility of obtaining a vulcanization spatial structure of different sulfide content: thiuram group accelerators promote the formation of mono-, disulfide bonds; guanidine — polysulfide bonds, and thiazole groups — from carbon-carbon to polysulfide with varying degrees of sulfide. According to the results of the study of physical and mechanical properties, the determination of the parameters of the spatial grid and the study of the dynamic behavior of rubber, differences were revealed due to the formation of a spatial structure with different types of cross-links and density. It is shown that rubber containing 1.5 pst. wt. MBT, 0.5 pst. wt. DFG and 0.5 – 1.0 pst.wt. TMTD due to the manifestation of a synergistic effect on the formation of a vulcanization network of a certain density and the ratio of poly-, di- and monosulfide cross-links. Thus, the use of a group of accelerators with different functional effects makes it possible to obtain vulcanizates with an optimal set of technological and operational properties.

Jamming carbonaceous nanofiller in the continuous phase and at the blend interface for phenomenal improvement in the overall physico-mechanical properties of compatibilized thermoplastic elastomer

Reduced graphene oxide (RGO) nanosheets have been selectively jammed in the continuous polypropylene (PP) phase and at the blend interface of random terpolymer of ethylene, acrylic ester and maleic anhydride (EAMAT) compatibilized PP and epichlorohydrin rubber (ECH) based thermoplastic elastomer (TPE). The presumptions from the contact angle studies regarding the preferential localization of RGO in the continuous PP phase and at the blend interface of compatibilized PP/ECH/EAMAT/RGO TPE nanocomposite have been analyzed via field emission scanning electron microscopy and atomic force microscopy. The presence of RGO in the continuous PP phase and at the blend interface results in a phenomenal improvement in the mechanical, rheological and viscoelastic properties of the compatibilized PP/ECH/EAMAT/RGO TPE nanocomposites. X-ray diffraction studies of the strained compatibilized PP/ECH/EAMAT/RGO TPE nanocomposite testify that, during straining, the RGO nanosheets help the PP chains to orient and consequently there is a prominent improvement in the overall physico-mechanical properties.

Influence of Vulcanizing System on Properties and Structure of Rubbers Based on Hydrin T6000 Epichlorohydrin Rubber

Influence of Vulcanizing System on Properties and Structure of Rubbers Based on Hydrin T6000 Epichlorohydrin Rubber

STUDY OF THE EFFECT OF DIOCTYL SEBACATE ON THE PROPERTIES OF EPICHLOROHYDRIN RUBBERS

The effect of different technologies for the introduction of a plasticizer - dioctyl sebacate on the properties of rubbers based on epichlorohydrin rubber of the Hydrin T-6000 brand was investigated. When using the technology of rubber swelling in a plasticizer, dioctyl sebacate exhibits a shielding effect, reducing the interaction of the filler-polymer, which leads to an improvement in low-temperature properties and a deterioration in the physical and mechanical properties of the material.

Effect of Production Technology of Hydrin T6000 Elastomers on Their Properties and Structure

The influence of the technology for producing elastomer materials based on epichlorohydrin rubber of Hydrin T6000 brand on physical-mechanical properties, structure formation, and frost resistance is studied. Differences in the properties of vulcanizates are revealed due to the formation of various sulfide bonds in a vulcanization network with different densities. The use of rubber swelling technology in a plasticizer leads to a screening effect, which reduces the interaction of the filler with the polymer. On the plus side, this effect improves low-temperature properties, and on the minus side, deteriorates physical-mechanical properties of the material.

Elastomeric composites for Arctic conditions: operation features and development experience

Operation of elastomeric materials in the extreme climatic conditions of the North is complex and expensive, since not always existing materials can provide the required level of low-temperature characteristics (down to - 60 °C). This leads to failure of machines and mechanisms, equipment downtime, additional costs for repair or replacement of elastomeric parts. This study investigates the features of elastomeric composites operation in cold climates and the results of full-scale tests with simultaneous exposure to naturally low temperatures and hydrocarbon environments in Yakutia (Siberia, Russia). It presents the main principles of creating elastomeric composites for sealing purposes with high frost resistance and examples of recent developments. To obtain elastomeric materials of high frost and oil resistance new rubbers of high frost resistance as Hydrin T6000 epichlorohydrin rubber (Tg = - 60 °C), and traditional rubbers (nitrile etc) were used. For elastomer modification we used carbon nanotubes, collagen hydrolysate and polymer mixtures. Different type of developed materials is a double-layer material based on ultra-high-molecular-weight polyethene (UHMWPE) and nitrile-butadiene rubber-based elastomeric composite. The effect of diphenylguanidine on the interaction of UHMWPE with elastomeric composite based on nitrile butadiene rubber and adhesion at the interface was investigated. The operating properties were studied by standard methods and the structure of the obtained materials was studied using electron microscopy.

Change in the Surface of Elastomers Based on Epichlorhydrin Rubber Modified by Functionalized Carbon Nanotubes

In this paper, we study the possibilities of the modification of epichlorohydrin rubbers by special-type functionalized carbon nanotubes activated by oxygen. The purpose of this modification is to improve the tribological properties and increase frost resistance. Two types of samples with the addition of 1 and 10% nanotubes are compared with the initial unmodified rubber. The operating conditions are simulated using tribological tests performed in the express mode. Electron microscopic surface studies of the initial elastomer and samples after tribological tests reveal a change. The introduction of nanotubes is shown to promote the formation of agglomerates of a characteristic shape, increasing the surface uniformity, and its greater stability during friction. Differences in the surface topography are already evident in samples with 1% nanotubes and noticeably increase in samples with 10% nanotubes. Using scanning probe microscopy, sample sections (topography and elastic properties) are studied after tribological tests. The surface at the cut edge is found to be denser and smoother than in the bulk layers of the sample as the elastic moduli of these regions are almost identical. The introduction of activated functionalized carbon nanotubes into epichlorohydrin rubber is shown to lead to hardening of the elastomer and increases its wear resistance.

Investigation of the effect of plasticizer injection technology on the properties of epichlorohydrin rubbers

The influence of preliminary swelling of epichlorohydrin rubber of the brand is investigated Hydrin Т6000 in dioctyl adipate and dioctyl sebacate on the Physicomechanical characteristics and frost resistance of its vulcanizates. Revealed that pre-swelling of the rubber in the plasticizer, the plasticizer penetrates into the intermolecular space of the rubber and due to the shielding effect reduces the interaction of the filler with the elastomer matrix, which simultaneously leads to improved low-temperature properties and decrease of Physicomechanical properties of vulcanizates.

Unique Compatibilized Thermoplastic Elastomer with High Strength and Remarkable Ductility: Effect of Multiple Point Interactions within a Rubber-Plastic Blend.

In the case of thermoplastic elastomers (TPEs) based on nonpolar polypropylene (PP) and polar rubbers, a small quantity of a third component known as the compatibilizer is added to maximize the compatibility between the incompatible blend components. Generally, one part of the compatibilizer reacts with the nonpolar PP phase and the other part of the compatibilizer reacts with the polar rubber phase, which in turn produces TPEs with useful properties. Till today, there have been no reports in the literature that examine the effect of a compatibilizer that can have multifaceted interactions with the incompatible blend components for the development of TPEs with unique properties. Accordingly, here, an ethylene-acrylic ester-maleic anhydride terpolymer (E-AE-MA-TP) has been used as the compatibilizer for the preparation of TPEs based on nonpolar isotactic polypropylene (i-PP) and polar epichlorohydrin rubber (ECR). The E-AE-MA-TP compatibilizer contains ethylene groups, acrylic groups, and anhydride/acid groups along its backbone, which act as the sites for establishing multifaceted interactions with both i-PP and ECR. The compatibilization efficiency of the E-AE-MA-TP compatibilizer has been analyzed by contact angle measurements, Fourier transform infrared (FTIR) spectroscopy, tensile stress–strain studies, mixing torque profiles, rheological studies, differential scanning calorimetry (DSC), field emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM) images. The particle size of the dispersed ECR domains in the i-PP matrix of the i-PP/ECR blend prominently decreases (∼90% reduction) by incorporation of a very low dosage (5 wt %) of the E-AE-MA-TP compatibilizer. The i-PP/ECR (40 wt %/60 wt %) blend containing 5 wt % compatibilizer displays outstanding mechanical properties (especially strain at break value (∼370%)), which are superior to the mechanical properties of several compatibilized TPEs (based on PP and polar rubbers) reported in the literature. The unique properties of TPEs based on i-PP and ECR in the presence of the E-AE-MA-TP compatibilizer is attributed to the efficacy of the E-AE-MA-TP compatibilizer to establish multifaceted interactions with both i-PP and ECR.

Investigation of the Climatic Stability of Sealing Rubbers Used in the Technology of the North

The present paper outlines the results of full-scale tests of climatic stability of rubbers based on BNKS-18 (butadiene-nitrile rubber) and Hydrin T6000 epichlorohydrin rubber containing low-volatile and non-toxic phenolic antioxidants. Samples are exposed in an open ground under natural conditions of exposure to climatic external factors of Yakutsk in the Republic of Sakha (Yakutia), as well as in deformed state (by 30%). Such indexes of the samples as conditional tensile strength, elongation at break are measured to determine the resistance of rubbers to aging after the first, third, sixth, ninth, twelfth and eighteenth months of exposing. The results of the study reveal the contribution of CO3 stabilizer in maintaining the stability of the physical and mechanical properties of BNKS-18: rubber containing CO3 has less property changes in the open air. Stafen stabilizer occurred more effective for the rubber based on Hydrin T6000: Over the entire period of full-scale exposure, rubber samples containing it demonstrated the smallest changes in the indicators of elastic-strength properties as compared to the industrial stabilizer 6РРD and other experimental stabilizers.

Study of the Topography and Properties of Surface Layers in Frost-Resistant Rubbers Modified with Carbon Nanotubes

The possibilities of creating new types of frost-resistant rubbers by using carbon nanotubes as a filler (modifier) for an elastomeric base (epichlorohydrin rubber) are studied. Samples with a nanotube content of 1 and 10% and the initial unmodified sample are compared. The initial samples and the samples after tribological tests are studied by the method of scanning electron microscopy (with elemental analysis). The method of scanning probe microscopy is used to study the surface topography and the physicomechanical properties (modulus of elasticity and adhesion). The addition of carbon nanotubes to the elastomer is shown to stabilize its composition and to result in structuring of the elastomeric base. The investigation of sample slices prepared after tribological testing makes it possible to distinguish several areas: thin “surface” (a thickness of 10–15 μm) and “near-surface” layers. Strong element redistribution is recorded, i.e., the concentration of sulfur and zinc increases significantly on the surface. It is shown that during tribological tests, the main changes occur mostly in the surface layer, while the near-surface layer does not transform so considerably. It is established that the addition of carbon nanotubes leads to an increase in the modulus of elasticity in the near-surface layers.

Evaluation of the performance of sealing rubbers operated in conditions of abrasive wear and low temperatures

The studied materials based on the new rubbers of unique frost resistance -propylene oxide rubber (Tg = -74 °C) and Hydrin T6000 epichlorohydrin rubber are recommended to be used as static and dynamic sealing parts for the equipment operated in the North. This was based on the full-scale tests in cold climates (Republic of Sakha (Yakutia)) and evaluation of tribological characteristics (coefficient of friction) at negative temperatures. The standard techniques were used in assessing of the changes of the physical and mechanical, relaxation, and low-temperature characteristics of model rubbers after aging. A special testing unit and a method for conducting the tests were developed to estimate the coefficient of friction at low temperatures.

Влияние вулканизующей системы на свойства и структуру резин на основе эпихлоргидринового каучука марки HydrinT6000

Влияние вулканизующей системы на свойства и структуру резин на основе эпихлоргидринового каучука марки HydrinT6000

Study on the Influence of Activated Carbon Nanotubes on the Tribological Properties of Frost-Resistant Rubber

This article presents results on studying effect of multi-walled carbon nanotubes (CNTs) on the tribological properties of frost-resistant rubber based on epichlorohydrin rubber. The sliding friction coefficient has been determined using a laboratory tribometer according to the “rubber ring-smooth steel disk” contact scheme. Rubber samples have been tested under conditions of dry friction for ranges of normal pressures of 0.1 … 0.4 MPa, sliding velocities of 1 … 100 mm/s for two values of the bulk temperature: 23 and −25° C. The wear rate of the samples has been determined at a temperature of 23° C, pressure of 0.4 MPa, and sliding speed of 10 mm/s. As a counterbody in experiments on the wear resistance assessment, sandpaper made of silicon carbide with a grain size of 120 and 250 microns has been used. It has been found that using CNTs as a filler for studied rubbers leads to an increase in their wear resistance. There is a multiple decrease in the wear rate when filling rubber with a small amount of CNTs (1–2 pts. wt. per 100 pts. wt. of rubber). Moreover, an improvement in physical and mechanical characteristics while maintaining high frost resistance is established. The addition of CNTs to the studied rubbers does not affect the static coefficient of friction.

Unique compatibilized thermoplastic elastomer from polypropylene and epichlorohydrin rubber

Thermoplastic elastomer (TPE) based on polypropylene (PP) and epichlorohydrin rubber (ECH) was prepared in the presence of maleic anhydride grafted polypropylene (MA-g-PP) as compatibilizer. The PP/ECH blends in the absence of compatibilizer showed very poor mechanical properties, especially low elongation at break values and higher tension set values. This was attributed to the poor compatibility between PP and ECH. On the other hand, in the case of compatibilized PP/ECH blends, MA-g-PP acted as a strong interfacial agent between PP and ECH phases and led to outstanding improvement in the mechanical and rheological properties. Compatibilized PP/ECH blends showed higher mixing torque values in comparison to the incompatible PP/ECH blends due to existence of better interaction between PP and ECH in the presence of MA-g-PP. Fourier transform infrared spectroscopy (FTIR) study clearly depicted the existence of strong chemical interactions between PP and ECH in the presence of MA-g-PP. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies suggested that the addition of MA-g-PP to PP/ECH blends increased the percentage crystallinity, which in turn enhanced the overall properties. Morphological studies clearly showed the prominent reduction in the domain size of dispersed ECH phase in the continuous PP matrix due to the incorporation of MA-g-PP as compatibilizer.

Collagen-containing products derived from the swim bladders of northern fish and their application

In recent years biologically active compounds are widely used in development of new polymer composite materials. In this study, collagen hydrolysate was obtained from the swim bladder of northern species of fish with alkali-salt hydrolysis followed by freeze-drying. Collagen hydrolysate has been added to rubbers based on epichlorohydrin rubber (GPCO) HYDRIN T6000 in order to improve the performance properties of the investigated rubber. The vulcanization parameter, mechanical and relaxation properties of the rubber blends containing the collagen hydrolysate have been discussed. The amino acid compositions, properties, the particle size of collagen hydrolysate have been studied. It was found that the tear resistance and compression set were significantly improved with the addition of collagen hydrolysate.