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Polyoxyethylated hydroxy benzyl oleamide has found use in lubricants to prevent adhesion in moulds during the production of vulcanizates of natural and of synthetic rubbers. Polyoxyethylated oleamide acts as a mould lubricant for synthetic rubbers, whilst polyglycol 400 dilaurate can be used to reduce the time and temperature necessary for the recovery of old vulcanizates using paraffin oil and bitumen. Anti‐fogging properties can be sustained in rubber hydrochloride films by the use of polyglycol 1500 dilaurate, and improved percentage elongation can be promoted in intimate blends of polystyrene and SBR rubbers by the inclusion of polyglycol 4000 monostearate. Polyoxyethylated sorbitan monostearate acts as an emulsifer in the emulsion polymerisation of styrene, butadiene and styrene/ butadiene copolymer rubbers, and it can perform as an anti‐static for the latter. Polyoxyethylated stearylamine can be incorporated into lubricants designed to prevent adhesion in moulds during production of vulcanizates of synthetic and of natural rubber, and rubber latexes and other aqueous dispersions of rubber can be rendered more stable by the employment of polyoxyethylated stearyl alcohol, and thus allow storage in untreated containers for long periods of time. Polyoxypropylated sorbitan monopalmitate will serve as a parting agent, releasing aid, for unvulcanized rubber and vulcanized rubber, without interfering with further bonding and coating of rubber.

In continuation to the previous work on copper (lignin/silica/fatty acids) (Cu-LSF) complex as a natural antioxidant/electrical conductivity agent for nitrile-butadiene rubber (NBR), this study aims to perform further investigations for NBR vulcanizates loaded with different concentrations of Cu-LSF complex, including swelling behavior and hardness properties, as well as evaluating their thermal stability via thermogravimetric analysis.

The behavior of Cu-LSF complex in NBR matrix was compared with that of the standard commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline/N-isopropyl-N′-phenyl-p-phenylenediamine [TMQ/IPPD]).

Results revealed that Cu-LSF complex can act as an effective reinforcing and hardening agent, with exhibiting fluid resistance, even when compared with the commercial antioxidants. In comparison with the previous studies on its Zn and Ca analogues and their behavior in different rubber matrixes, Cu-LSF complex showed higher values of hardness and less susceptibility for swelling, respectively. Moreover, Cu-LSF antioxidant activity becomes in accordance with the previous work.

The new Cu-LSF complex could be used as a green alternative to the commercial antioxidants (TMQ/IPPD) with introducing further advantages to the rubber matrix, such as hardening, fluid resistance and thermal stability.

This study aims to investigate the swelling behavior, mechanical and thermal properties of ternary rubber blend composites prepared by melt blending based on carbon black (CB)-filled natural rubber (NR)/styrene-butadiene rubber (SBR)/nitrile butadiene rubber (NBR) blends, containing a variety of compatibilizers. Various compatibilizers, maleic acid anhydride (MAH), prepared emulsion and adhesion system (HRH) were used. A series of NR/SBR/NBR blends at a 30/30/40 blend ratio reinforced with 45 phr of CB were prepared using the master-batch method.

Thermal aging properties of the composites characterized by their aging coefficient and retention in tensile and elongation at break (E.B. %). Thermal degradation of ternary rubber blend composites based on melt blending has been studied using thermogravimetric analysis.

The swelling coefficient decreased with increased compatibilizer loading. Results also showed that the tensile strength and E.B. (%) decreased with aging over the entire aging period. Additionally, the addition of compatibilizers into the ternary rubber blend composite had slightly improved the thermal stability.

Interactions between the different components of blends at the interfaces have a high impact on the interfacial properties of the rubber blend.

Compatibilizers significantly improve the properties of the resulting composites with the loading of investigated compatibilizers because of the uniform dispersion of CB in the rubber matrix.

Using blends in the rubber industry led to the high-efficiency production of low-cost products.

The rubber blending has a significant positive effect on a wide range of applications such as structural applications, aerospace, military, packaging, tires and biomedical, so improving the compatibility of blends will make new materials suitable for new applications.

This paper aims to study the effects of various compatibilisers (maleic anhydride (MAH), methyl methacrylate/butyl acrylate emulsion lattice, and adhesion system (HRH)) on properties of carbon black (CB) filled with natural rubber (NR)/styrene-butadiene rubber (SBR)/ nitrile butadiene rubber (NBR) blends). A series of NR/SBR/NBR blends at a 30/30/40 blend ratio reinforced with 45 phr of CB was prepared using the master-batch method.

The tensile properties such as the tensile strength, stress at 100, 200 and 300% elongations, and elongation at break (EB)% were studied. Additionally, the morphological properties of compatibilised and uncompatibilised composites were compared to determine the optimal compatibiliser content.

The influence of compatibilisers appeared on all the properties studied. The properties of the blends compatibilised with prepared emulsion are very distinct from those of blends compatibilised with MAH and adhesion systems.

Interactions among the different components of blends at the interfaces have a high impact on the interfacial properties of the rubber blend.

Compatibilisers significantly improve the physicomechanical properties of the resulting composites with the loading of investigated compatibilisers because of the uniform dispersion of CB in the rubber matrix.

Using blends in the rubber industry leads to high-efficiency production of low-cost products.

The rubber blending has a significant positive effect on a wide range of applications such as structural applications, aerospace, military, packaging, tires and biomedical. Hence, improving the compatibility of blends will make new materials suitable for new applications.

One of the low-cost minerals that can be used as reinforcing filler in polymer industry is pumice powder. Pumice is a highly porous volcanic glass formed during explosive eruptions. This pumice has received significant interest because of its large surface area with various polar groups and can be processed easily.

This study is carried out to investigate the effect of partial replacement of silica (as traditional filler) by naturally occurring pumice powder to improve the thermal and mechanical properties of nitrile butadiene rubber cured with electron beam radiation (doses from 25 to 150 kGy).

The results indicated that the addition of pumice powder increase the tensile strength at lower doses up to 75 kGy (especially at concentration of 5 phr). Besides, an improvement in the thermal stability was attained with the addition of pumice powder.

Pumice powder is volcanic-based alumina and silica which is mainly composed of SiO₂. It has porous structure which is formed by dissolved gases precipitated during the cooling as the lava hurtles through air. Due to its porous structure, it has low density and high thermal insulation. It also has high temperature and chemical resistance, for these reasons it became preferable material to be used as filler in the plastic and rubber industry.

There are different techniques in practice to disperse multiwalled carbon nanotubes (MWCNTs) in elastomers. In the present work, commercially available MWCNTs NANOCYL NC 7000™ are used as filler. A synthetic Nitrile Butadiene Rubber (NBR) and Hydrogenated Nitrile Butadiene Rubber (HNBR) were used as polymer matrix for the composites prepared by melt blending. The filler dispersion in HNBR was studied through Transmission Electron Microscopy (TEM). The mechanical properties are investigated through strain sweep and tensile tests. Dielectric measurements are carried out to study electrical conductivity of the nanocomposites. Dynamic mechanical measurements showed an enhanced Payne effect and improvement in stiffness with increase in CNTs content into rubber matrix An improvement in electrical and mechanical properties in both NBR and HNBR system resulted by an increase in filler loading. The mechanical and electric percolation threshold of CNTs was found at very low filler volume fraction. Equilibrium swelling experiments were used to study polymer-filler interaction with the help of Kraus plot and diffusion coefficient. NBR showed higher polymer-filler interaction compared to HNBR. In NBR nanocomposites, CNTs showed higher interaction than carbon black. Good dispersion and effective interaction of the CNTs with the polymer led to significant mechanical reinforcing effects.

This study aims to investigate the behavior of the green biomass-derived copper (lignin/silica/fatty acids) complex, copper lignin/silica/fatty acids (Cu-LSF) complex, when incorporated into the nonpolar ethylene propylene diene (EPDFM) rubber matrix, focusing on its reinforcing and antioxidant effect on the resulting EPDM composites.

The structure of the prepared EPDM composites was confirmed by Fourier-transform infrared spectroscopy, and the dispersion of the additive fillers and antioxidants in the EPDM matrix was investigated using scanning electron microscopy. Also, the rheometric characteristics, mechanical properties, swelling behavior and thermal gravimetric analysis of all the prepared EPDM composites were explored as well.

Results revealed that the Cu-LSF complex dispersed well in the nonpolar EPDM rubber matrix, in thepresence of coupling system, with enhanced Cu-LSF-rubber interactions and increased cross-linking density, which reflected on the improved rheological and mechanical properties of the resulting EPDM composites. From the various investigations performed in the current study, the authors can suggest 7–11 phr is the optimal effective concentration of Cu-LSF complex loading. Interestingly, EPDM composites containing Cu-LSF complex showed better antiaging performance, thermal stability and fluid resistance, when compared with those containing the commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline and N-isopropyl-N’-phenyl-p-phenylenediamine). These findings are in good agreement with our previous study on polar nitrile butadiene rubber.

The current study suggests the green biomass-derived Cu-LSF complex to be a promising low-cost and environmentally safe alternative filler and antioxidant to the hazardous commercial ones.

This paper aims to explore the possibility of converting the nitrile butadiene rubber (NBR) water-lubricated bearing material into a self-lubricating bearing material by the action of polytetrafluoroethylene (PTFE) particles and water lubrication.

A group of experimental studies was carried out on a ring-on-block friction test. The physical properties, tribological properties and interface structure of PTFE-NBR self-lubricating composites filled with different percentages of PTFE particles were investigated.

The experimental results indicated that the reduction in friction and wear is a result of the formation of the lubricating film on the surface of the composites. The lubricating film was formed of a large amount of PTFE particles continuously supplied under water lubrication conditions and the PTFE particles here can greatly enhance the load capacity and lubrication performance.

In this study, the tribological properties of PTFE particles added to the NBR water-lubricated bearing materials under water lubrication were investigated experimentally, and the research was carried out by a ring-on-block friction test. It is believed that this study can provide some guidance for the application of PTFE-NBR self-lubricating.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0187/

TO THE SEAL manufacturer, the whole question of sealing is a complex and profound subject, but it is his aim to make it as simple as possible to the people who will actually depend upon the efficient functioning of his product. We have come a long way since the days when oiled lengths of leather and rope were wound into inadequate glands, for it became obvious, almost from the outset, that a more reliable means of sealing had to be discovered. Loss of system pressure, and loss of lubricant can bring machinery to a grinding halt.

The tribological behavior, i.e. friction coefficient and wear rate, and vibration characteristics of the water-lubricated bearing was investigated. The water-lubricated bearing is made of three different materials, i.e. polyether-ether-ketone (PEEK), polyimide (PI) and nitrile-butadiene rubber (NBR).

The tribological behavior was investigated experimentally on a specially designed test rig. Three vibration sensors were used to record the vibration of the bearing.

The results indicated that the variation of friction coefficient with rotation speed agrees well with the trend of Stribeck curve. The tested friction coefficient of rubber bearing is higher than that of the other two bearings whether it is in the state of mixed-lubrication or hydrodynamic lubrication, and which causing a larger wear rate in rubber bearing. The PEEK bearing exhibits the best tribological properties due to it has smaller friction coefficient and wear rate. However, it can be found that the rubber bearing gives the minimum vibration acceleration, which means that the rubber bearing has the most potential to improve the stability of water-lubricated bearing rotor system.

In this study, a group of experiment studies conducted on a specially designed test rig. The comprehensive performance, including friction coefficient, vibration acceleration and wear rate, of water-lubricated bearing with three different materials, i.e. PEEK, PI and NBR, was compared systematically. The experiment research may offer a reference for the selection of material in water-lubricated bearing in specific operating conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0447/