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To investigate the dielectric strength and mechanical features of modified nitrile butadiene rubber (NBR), titanium dioxide (TiO 2) and magnesium oxide (MgO) nanoparticles have been used. Specimens have been experimentally prepared with loading various concentrations (0.5, 1, 1.5 and 3 parts per hundred part of rubber "Phr") to NBR base material. The dielectric strength has been evaluated by applying AC high voltage on the prepared samples up to reaching the breakdown state. On the other hand tensile strength, elongation at break and modulus at 100% elongation have been experimented to exploration the mechanical features of the NBR enhanced by nanoparticles. Although all the recorded results of modified NBR samples showed improvement more than the base material at dielectric, tensile strength and modulus at 100% elongation tests. The elongation at break result showed a negative impact; it was caused by forming a new links between NBR and nanoparticles. The dielectric constants of applied nanoparticles are greater than NBR base materials, which can physically explain the improvement in all recorded breakdown results. But the enhancement in the measured mechanical features can be attributed to chemical bonds which were reconstructed and the gaps of NBR base material that had been filled. [ABSTRACT FROM AUTHOR]

In this work, waste nitrile rubber (NBR) was radio-chemo-mechanically devulcanized and used as oil/seawater separator. Pure and surface modified silica nanoparticles were applied to the new and recycled NBR compounds at different contents (i.e. 1, 2, 3, 5 and 10 wt%). The surface modification of nanoparticles was performed using triethoxyvinylsilane (TEVS) at different concentrations (i.e. 1, 5 and 10X). The rheological/mechanical properties and water/oil contact angles (WCA/OCA) of the new and recycled NBR based nanocomposites were evaluated. The results showed that using modified silica nanoparticles (at 5 wt% loading content) caused increment in the WCA from 89.89 and 95.3° to 151.56 and 153.3° and decrease in the OCA from 73.39 and 71.3° to 14.1 and 11.1° for new and recycled NBRs, respectively. It was also found that durability of sorbent against oil absorption–desorption cycles declined using the recycled rubber instead of new NBR compound (i.e. from 1000 to 700 cycles), but the oil absorption capacity enhanced (i.e. from 2.2 to 2.4 g/g). The oil separation efficiencies (OSE) of the modified nanocomposites were more than 99%. It was shown that using modified nanoparticles in RNBR caused 50% decrement in the Payne effect and 33% enhancement in the chemical/physical bonds, respectively. [ABSTRACT FROM AUTHOR]

The failure or damage of metal joints in many mining equipments can shut down the whole machinery. This problem can be solved by employing wearresistant, non-corrosive, and shock-resistant rubbers, such as Acrylonitrile butadiene rubber (ABR), at the critical joints. These components are made mostly by molding, followed by machining. Transferring used molds to other working units is complicated, necessitating a different way of producing rubber components. Machining such components using a suspension-type abrasive water jet (AWJ) machine is possible. But high kerf taper ratio (KTR) and low material removal rate (MRR) are observed due to the viscoelastic behavior and elastic deformation throughout the rubber during machining. However, machining rubber at its glass transition temperature (Tg) range can solve the high elasticity problems encountered during its room-temperature machining. Hence, the study focuses on machining 15 mm thick ABR under conventional (room) and low-temperature conditions using suspension-type AWJ. The water jet pressure (WJP), traverse rate (Vf), and stand-off distance (SOD) are the process parameters. This work confirmed that the machining of ABR under lowtemperature conditions produced low KTR and high MRR and reduced the amount of embedded Garnet particles at the machined ABR surface significantly. [ABSTRACT FROM AUTHOR]

Light-curing resin cements, each comprising one of five different inorganic fillers (non-porous and porous spherical SiO2 particles, irregularly shaped glass and ZrO2 particles, and porous ZrO2 spheres), monomers, and polymerization initiators were prepared to determine the effect of filler morphology on the adhesive strength of the resin cement. The strength of adhesion to a computeraided design/computer-aided manufacturing (CAD/CAM) resin block was investigated mechanically by measuring the tensile bond strength, flexural strength, and elastic modulus. The resin cement containing sub-micron porous ZrO2 spheres had significantly higher tensile bond strength than the other resin cements. The resin cement containing the porous ZrO2 spheres had markedly lower flexural strength and elastic modulus values than the resin cements containing SiO2 and glass fillers. [ABSTRACT FROM AUTHOR]

An automotive sealed chain consisting of an elastomeric seal between chain plates prevents the entry of external contaminants. But, the presence of a seal induces high transmission loss due to the frictional force. In the present study, a comparative transmission loss test between two ANSI-B29.1 520 series sealed chains of equal geometric dimensions (5/8" pitch) was carried out. The tests revealed a significant difference of 38% in their transmission losses between the chains. To understand these observed differences in the chain performance, the material analysis of the seals (nitrile butadiene rubber) was performed, which showed a significant difference in their composition. The increased seal hardness due to difference in chemical properties resulted in a 21% increase in friction coefficient between the seal and the plates. The seal thickness reduction, the effect of lubricant, and the difference in the frictional forces between chains yielded differences in the transmission losses. [ABSTRACT FROM AUTHOR]

A key for the market penetration of large-scale and high energy All-Solid-State Batteries (ASSBs) are sheet-type cell components. Herein, we report a slurry-based process to obtain free-standing solid electrolyte (SE)/binder composite sheets as ASSB separators. We investigate three different sulfidic solid electrolyte systems (Li6PS5Cl, Li7P3S11 and Li10SnP2S12) in combination with a hydrogenated nitrile butadiene rubber (HNBR). By means of electrochemical impedance spectroscopy (EIS), the influence of separator composition and processing on the ionic sheet conductivity is evaluated. Independent of the solid electrolyte material, a reduction by a factor of three compared to the pristine powder conductivity at 70 MPa operation pressure and by a factor of eight compared to the maximum powder conductivity is observed. This can be attributed to the addition of the ionically isolating binder, which however is necessary for the production of freestanding sheets. We show the beneficial effect of pre-compressing the sheets to little porosity values on the apparent sheet conductivity. Lastly, we investigate and decouple the influence of fabrication and operating cell pressure on the produced separator sheets. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of surface reaction-type pre-reacted glass-ionomer (S-PRG) filler eluate on Matrix metalloproteinase (MMP)-1 and MMP-3 secretion by human gingival fibroblasts (HGF). The S-PRG filler eluate contains 6 ions (F, Na, Al, B, Sr and Si) released from the S-PRG filler. The S-PRG filler eluate stimulation induced a slight secretion of MMP-1 and MMP-3 by HGF. It also enhanced the phosphorylation of p38 and ERK. The increase in MMP-1 and MMP-3 secretion by the inflammatory cytokine TNF-α was suppressed by the S-PRG filler eluate. TNF-α-induced increases in the phosphorylation of ERK were slightly enhanced by S-PRG filler eluate. These findings may prompt the development of new therapeutic agents for oral inflammation with materials composed of S-PRG filler eluate. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Six different polymeric matrices were fabricated to reduce the sensitivity of PETN (Pentaerythritol tetranitrate). The polymeric matrices used were individually based on Acrylonitrile butadiene rubber (NBR) softened by plasticizer, styrene-butadiene rubber (SBR) softened by oil, polymethyl methacrylate (PMMA) plasticised by dioctyl adipate (DOA), polydimethylsiloxane (PDMS), polyurethane matrix, and Fluorel binder. A computerised plastograph mixer was utilised for producing three polymer-bonded explosives (PETN-NBR, PETN-SBR, and PETN-PDMS) based on the non-aqueous method. A cast-cured method was used to prepare PBX based on polyurethane (PETN-HTPB), while the slurry technique was used to prepare beads of PETN coated by either fluorel binder (PETN-FL) or based on PMMA forming (PETN-PMMA). The heat of combustion and sensitivities were investigated. The velocity of detonation was measured, while the characteristics of the detonation wave were deduced theoretically by the EXPLO 5 (thermodynamic code). The ballistic mortar experiment was performed to determine the explosive strength. By comparing the results, it was found that PDMS has the highest influence on decreasing the impact sensitivity of PETN, while the cast cured PETN-HTPB has the lowest friction sensitivity. On the other side, PETN-FL has the highest detonation parameters with high impact sensitivity. Several relationships were verified and the matching between the measured results with the calculated ones was confirmed. [ABSTRACT FROM AUTHOR]

The article presents several products including Conval's Camseal in-line ball valve; Dump Clean bag break station from the Automated Flexible Conveyor, Inc.; and the BULK-OUT BFC bulk bag discharging system from the Flexicon.

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acrylonitrile butadiene rubber (NBR)/ eggshell powder (ESP) composite film was produced using latex compounding and curing technique. ESP loading was varied from 0,2, 4 to 6 phr. The composite films cured at 80 °C for 120 min. All the composite films exhibit superior tensile strength and Young Modulus compared to pure NBR control film. The dispersion of ESP in the tensile fracture surface was homogenous with no agglomeration observed up to 6 phr loading. Resistance to chemical degradation and swelling increased with increment of filler loading in the NBR films. This is due to the good interaction between ESP and NBR macromolecular chains, which causes mechanical interlocking of the chain on the surface of the filler and thus reduces the free volume and flexibility of the chain. The finding proves that ESP has a large potential to be use as bio- filler in production of NBR film Type I and II. [ABSTRACT FROM AUTHOR]

This study sought to investigate the tribological properties of nitrile rubber (NBR)/ultrahigh molecular weight polyethylene (UHMWPE)/nano-molybdenum disulfide (nano-MoS2) nanocomposites containing various quantities of nano-MoS2. The apparatus used for these tests was a marine stern tube bearing testing apparatus SSB-100V that was water-lubricated and was run at low speed under heavy duty conditions. The coefficient of friction coefficient (COF), wear rate, and surface abrasion of the composite were obtained to determine the effect of the addition nano-MoS2 and to obtain the optimum nano-MoS2 content. The mechanical and physical properties of the rubber-plastic material met the requirements of the Chinese Ship standard CB/T769-2008 and U.S. military standard MIL-DTL-17901C(SH). The experimental results showed that the nanocomposites that contained 9 phr nano-MoS2 (parts by weight per hundred parts of rubber materials) exhibited good comprehensive friction and wear properties. It is believed that the experience achieved from this study can form a theoretical foundation for the improving the properties of the subject rubber-plastic material. [ABSTRACT FROM AUTHOR]

A potential high durable heterogeneous catalyst for the industrial selective hydrogenation of nitrile butadiene rubber (NBR) has been established by immobilizing palladium (Pd) nanoparticles on macroporous hollow silica (MHS) microspheres in the present work. Compared with the Pd nanoparticles supported on macroporous hollow silica (Pd/MHS) via conversional incipient wetness impregnation with different free chelating reagents (HCl or EDTA) catalysts, the Pd nanoparticles supported on the modified macroporous hollow silica (Pd/M-MHS) catalyst showed better distribution of Pd nanoparticles and catalytic performance. High hydrogenation degree (HD) toward the –CH CH– group of 97% was achieved in acetone solution at 70 °C with H 2 pressure of 4.5 MPa for 6 h, while the nitrile (–C N) group had not been hydrogenated in the reaction. And there was no obvious change in the relative molecular weight and polydispersion index of the product in comparison with the raw NBR. The HD for the 5th reuse was 90.5%, remaining more than 93% of its HD for the original time, demonstrating its high durable activity. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glass fiber composite materials in epoxy resin with different content of a nitrile rubber modified hybrid resin were manufactured by infusion with two different rubber concentrations. SX 10 epoxy resin was modified to improve the response of the laminates under impact loads. At the aim to test the improvement of the impact resistance over the conventional epoxy resin system, the rectangular specimens 100*150 mm 2 were dynamically loaded in the center by a falling weight machine, Ceast Fractovis, using a cylindrical impactor with a hemispherical nose 19,8 mm in diameter and a total mass of 3.6 kg. Impact tests were carried out at penetration to obtain the complete load-displacement curve useful to measure the penetration energy and to highlight the characteristics points for the increasing energies evaluation, 5J, 10J and 20J, to investigate the damage start and propagation. After the impact tests, the specimens were observed by visual inspection to investigate the delamination extension whereas a confocal microscope was used for the indentation measurements. The obtained results on the modified epoxy system were compared to neat GFRP laminates impact performances. No significant impact performance difference was recorded between samples with different nitrile rubber modifier content. A higher indentation was recorded on the modified samples related with a lower delamination extension. It could represent a good practical results since from a simple external damage measurement it can be possible to obtain information about a low internal delamination. [ABSTRACT FROM AUTHOR]

The effect of silica loading on the static frictional coefficient of nitrile rubber when paired with different types of papers is investigated. The influence of silica loading on the mechanical properties of nitrile rubber and its changes due to natural ageing is also examined. The objective of the study is to generate data for assessing the suitability of NBR as a lining material for impactive grippers. It is observed that the properties of NBR including frictional coefficient can be modified by varying the amount of silica. The static co-efficient of friction with most of the papers is highest at around 55 phr of silica. The properties like hardness, tear strength and resistance to oil increase with the amount of silica content while swelling index decrease with silica loading and the abrasion index peaks around 55 phr. The change in the mechanical properties due to natural ageing varies, though marginally. [ABSTRACT FROM AUTHOR]

The article evaluates the SmartSkin nitrile gloves from Brass Knuckle Safety Products.

The article evaluates anti-slip access platforms, from Flexicon, that allow workers to safely reach elevated process equipment, eliminating the need for ladders, scissor lifts, and forklift cages.

Polymer wastes and oil slicks are environmental threats in the present century. Accordingly, the reuse of polymer wastes to absorb oil slicks could be an interesting topic. In this research, devulcanized nitrile rubber (DNBR) as oil resistant/recycled material were used to prepare an environmental friendly superhydrophobic/superoleophilic oil sorbent. For this purpose, silica nanoparticles were silanized using vinyltriethoxysilane. HR-TEM, FTIR and XPS analysis were performed to characterize the surface morphology and chemical composition of the pure and silanized nanoparticles. The grafted nano silica illustrated superhydrophobic behavior due to water droplet contact angle which was 156 compared to 53° for pure nano silica. XPS analysis showed that the content of Si, O and C elements on the surface of modified nano silica increased by 18%, 8% and 25%, respectively, compared to pure nano silica. The chemo-thermo-mechanical properties of the DNBR nanocomposites contained 6 phr of pure and silanized nanoparticles were evaluated. Results confirmed improvement in the curing and mechanical performances of the rubbery nanocomposite due to silane grafting. The modified nanocomposite had the highest oil absorption capacity over 2.4 g.g− 1 (i.e. for dense sheet). It efficiently separated about 91% of Persian Gulf oil/water mixtures with remarkable reusability of about 700 cycles. [Display omitted] • Recycled/Devulcanized nitrile rubber (DNBR) were used for preparation of nanocomposites. • Nano silica was surface modified by vinyltriethoxysilane and characterized carefully. • Nano silica containing DNBR based nanocomposites were fabricated. • Surface and mechanical properties of the nanocomposites were evaluated. • Oil/water separation capacity of the nanocomposites were studied. [ABSTRACT FROM AUTHOR]

Electrically conducting nitrile rubber (NBR) containing electro-conductive carbon black (CB) and polypyrrole as conducting-modifier were prepared by single-step in situ polymerization with mechanical mixing and compression molding (vulcanized). Our result showed CB/NBR and CB/ polypyrrole /NBR conducting composites presents high thermal stability. Thermo-gravimetric analysis showed that the CB 50 phr / polypyrrole 10 phr /NBR of composites formula has highest thermal stability with improved degradation temperature from 422 °C (NBR matrix) to 440 °C at 10% weight loss. CB 50 phr and polypyrrole 10 phr has still optimum volume resistivity values 2.83×1010 to 2.03×103 ohm-cm above the percolation threshold. Therefore, incorporating CB with polypyrrole conducting-modifier showed four causes of advantage i.e. increase in thermal stability, conductive pathways, synergistic properties on thermal stability with reinforcement mechanical properties and compounding conductivity effect within the rubber matrix. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The viscoelastic behavior of hydrogenated nitrile butadiene rubber (HNBR) was studied over a range of temperatures and shear frequencies. Dynamic mechanical properties were studied and modelled using the generalized Maxwell model and the Williams-Landel-Ferry equation. A fitting algorithm was developed to provide the best agreement between the experimental data and the model results. In addition to dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) was applied. The HNBR structure was characterized by X-ray diffraction (XRD). The developed model exhibited an excellent agreement with either isothermal or dynamic experiment data, yet only up to the rubbery plateau, after which a structure ordering occurred. This was explained by the cyano group secondary bonding and consequentially the cross-linking between HNBR chains. A molecular modeling simulation was made to confirm the cross-linking. The effect of peroxide cross-linking agents in a compound resembled the one usually observed in the filler formulated compounds. [ABSTRACT FROM AUTHOR]

We investigated the photodegradation of vulcanized rubbers in solution by the radical initiator. α,α′-azobisisobutyronitrile (AIBN) that becomes an active initiator after fission of the C-N bond, under violet irradiation by a mercury lamp. We investigated the decrease in the molecular weight, of vulcanized rubber along with FT-IR and NMR studues of the irradiated polymers. The vulcanized rubber showed a remarkable molecular weight decrease, but which is less pronounced as compared with the diene polymer. This result indicates that the degradation of polymers proceeds by an auto-oxidation mechanism. [ABSTRACT FROM AUTHOR]

A reprint of the article "Making Sense of Glove Selection," by Rachelle Springer, which appeared in the book "Latex Allergies & Proper Glove Selection, Prevention Is the Best Cure: A Self-Study Guide," is presented. It discusses the importance of proper selection of a medical glove. It cites that the two most important attributes of a glove that need to be considered are barrier protection and allergen content. Different types of gloves are descibed, including natural rubber latex, nitrile latex and neoprene gloves.

Studies the formation mechanism of bound rubber in the composites prepared from precipitated silica and nitrile butadiene rubber (NBR) as a function of nitrile group content of NBR. Average size of agglomerate formed by silica particles in the composites; Infrared spectroscopy; Hydrogen bonding; Decrease in the amount of filler-gel entrapped in the agglomerate.

Analyzes the component of ozone-deteriorated nitrile rubber sheets containing additives by the pyrolysis gas chromatography/mass spectrometry method. Relationship between the decrease of the antioxidant and the mechanical strength of the sheet; Three peaks related to antioxidant.

As the core component of a fracturing tool, a rubber packer plays a vital role during the well stimulation process. Its sealing performance significantly affects the fracturing effects. This study adopted a 3D multi-body contact nonlinear finite element analysis with the Mooney–Rivlin constitutive model to investigate the sealing performance of the hydrogenated nitrile butadiene rubber. The effects of key parameters such as the total thickness, sub-thickness, height, and rubber hardness on the sealing performance were systemically investigated. Numerical results indicated that maximum contact stress appeared around the rubber packer's upper part because of the combined effect of friction and axial compression. Besides, the numerical results were validated with theoretical and experimental results, in which the error between theoretical and numerical results was less than 7%, and that between the numerical results and experimental results was approximately 17.7%. Under the conditions considered, key parameters of rubber packer were optimized as a total thickness of 20 mm, a sub-thickness of 13 mm, a height of 70 mm, and a hardness of 70 International Rubber Hardness Degrees, in terms of the maximum contact stress and deformation displacement. The proposed numerical approaches could accurately predict rubber packer's deformation status, which consequently had technical guiding significance for the design of similar sealing components in various applications. Image 1 • Effect of key parameters on the sealing performance of HNBR packer was studied. • Maximum stress appeared at packer's upper part due to friction and compression. • Contact stress was distributed unevenly and varied along the contact length. • The Packer's middle part first contacted the casing and formed arcuate curvature. [ABSTRACT FROM AUTHOR]

MOFs are usually used as efficient adsorbents to remove specific pollutants in water. However, because of their poor water stability relatively small particle size, their application in adsorbing and removing pollutants from water is limited. In this paper, with nitrile rubber sponge as the substrate, UiO-66-NH 2 /sponge composites were firstly in-situ synthesized and systematically evaluated UiO-66-NH 2 as an adsorbent to remove 2,4-dichlorophenoxyacetic acid from water. This composite could not only remain the adsorption capacity for 2,4-dichlorophenoxyacetic acid of UiO-66-NH 2 , but also was much more convenient for separation after the adsorption compared to UiO-66-NH 2. In addition, the mechanism of the adsorption of UiO-66-NH 2 for 2,4-dichlorophenoxyacetic acid were discussed in detail. Electrostatic interaction between UiO-66-NH 2 and 2,4-dichlorophenoxyacetic acid was the main adsorption mechanism. The adsorption was mainly suitable for Langmuir isotherm models, and its maximum adsorption capacity of 2,4-dichlorophenoxyacetic acid was 72.99 mg g−1. • UiO-66-NH 2 /sponge composites were firstly in-situ synthesized. • UiO-66-NH 2 adsorbs 2,4-D through electrostatic, hydrogen bond and π-π interaction. • The adsorption 2,4-D of UiO-66-NH 2 /sponge is similar to that of UiO-66-NH 2. [ABSTRACT FROM AUTHOR]