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The purpose of this paper is to investigate the effect of expandable graphite (EG) plates’ incorporation on the mechanical, thermal and fire-retardant properties of an epoxy–aliphatic amine system. In addition, the optimum amount of EG in epoxy/EG composites is determined to achieve the best thermal and mechanical properties at the same time.

The epoxy/EG composites were prepared by using (1-4) phr of EG. The morphological structure of epoxy/EG composites was studied by using scanning electron microscopy. The thermal, flame-retardant and mechanical properties of epoxy/EG composites were evaluated by using thermogravimetric analysis (TGA), oxygen index test and dynamic mechanical analysis and tensile and impact test, respectively.

TGA results showed that the incorporation of EG to the epoxy resin increased the initial decomposition temperature and residue weight of the composites. It was found that, with increasing EG concentration up to 4 phr, the oxygen index, glass transition temperature and Young’s modulus of epoxy/EG composites increased up to 60 per cent, 4.1°C and 50 per cent, respectively. On the other hand, the sample with 2 phr EG provided the maximum values of tensile strength, storage modulus, cross-linking density, ultimate tensile strain and impact strength.

Prepared epoxy/EG composites can be used as halogen-free flame-retardant composites. The proposed process for the preparation of the composites is simple and can easily be implicated in the industry.

To the best of the authors’ knowledge, there is no other publication that considers mechanical, thermal and fire-retardant properties of epoxy/EG composites in one paper. In this work, the optimum concentration of EG in epoxy/EG composites was determined, considering all these properties.

This paper aims to discuss the influence of graphite with varying purity on the tribological performance of brake pads.

Three distinct brake pads were created within the scope of this experiment by varying the graphite purity without affecting the other components. The brake pads were made using a traditional manufacturing procedure, and industry standards were used to test the chemical, physical and mechanical properties of the newly produced brake pad. A full-scale inertia brake dynamometer was used to determine the material’s tribological characteristics. The worn surfaces of the brake pads were examined using a scanning electron microscope.

The test results indicate that brake pads containing 99% pure graphite (artificial grade) displayed good physical, chemical and mechanical features, such as consistent friction and a reduced rate of wear because of the lower impurity level, which eliminates frictional undulations.

This paper discusses the influence of graphite purity on the tribological performance of brake pads by modifying tribofilms and reducing friction undulations.

This study aims to manufacture cotton fabric with thermal regulation performance by using the composite phase change material (CPCM) prepared by coating paraffin doped with expanded graphite (EG), and the thermal effect of the fabric material was evaluated and characterized.

EG/paraffin CPCM with shape stability and enhanced thermal conductivity were prepared by the impregnation method and then finished on the surface of cotton fabric with coating technology. The microstructure, crystal structure, chemical composition, latent heat property and thermal conductivity were analyzed by scanning electron microscope, x-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimeter and thermal constant analyzer. The photo-thermal effect of the coated fabric was studied by a thermal infrared imager.

CPCM prepared with a mass ratio of EG to paraffin of 1:8 showed excellent shape stability and low paraffin leakage rate. The latent heat of the CPCM was 51.6201 J/g and the thermal conductivity coefficient was increased by 11.4 times compared with the mixed paraffin. After the CPCM was coated on the surface of the cotton fabric, the light-to-heat conversion rate of the C-EG/PA3 sample was improved by 86.32% compared with the original fabric. In addition, the coated fabric showed excellent thermal stability and heat storage performance in the thermal cycling test.

EG can improve the shape stability and thermal conductivity of paraffin but will reduce the latent heat energy.

The method developed provided a simple and practical solution to improving the thermal regulation performance of fabrics.

Combining paraffin wax with fabrics in a composite way is innovative and has certain applicability in improving the thermal properties of fabrics.

Discusses the properties of various asbestos‐free gasket materials, in particular expanded PTFE. Presents the factors which need to be taken into account when choosing a gasket. Highlights the requirements of gaskets in the automotive industry and the conditions they have to withstand.

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

Graphite-based resistors were made of thick-film pastes with different graphite-to-glass mass fraction were prepared and examined. Sheet resistance, temperature coefficient of resistance, impact of humidity and short-term overload were investigated. The properties of the layers fired in atmospheres of air at 550°C and nitrogen at 875°C were compared.

Graphite-based resistors with various graphite-to-glass ratios made possible to obtain a wide range of sheet resistance from single O/square to few kO/square. These values were dependent on firing atmosphere, paste composition and the number of screen-printed layers. The samples made of paste with 1:1 graphite-to-glass ratio exhibited the temperature coefficient of resistance of about −1,000 ppm/°C, almost independently on the firing atmosphere and presence of a top coating. The resistors fired in the air after coating with overglaze, exhibited significantly lower sheet resistance, reduced impact of humidity and improved power capabilities.

In this paper, graphite-based resistors for applications in typical high-temperature cermet thick-film circuits were presented, whereas typical graphite-based resistors were fabricated in polymer thick-film technology. Owing to very low cost of the graphite, the material is suitable for low-power passive circuits, where components are not subjected into high temperature, above the typical temperature of operation of standard electronic components.

This study aims to fabricate and study the effect of five cumulative graphite (G) and graphite nanoplatelets (GNP) filler loading composites by polymerising PA6 precursor; monomer epsilon caprolactam with the two carbons in situ while taking cognisance of the mixing effects (simultaneous stirring and sonication at varying amplitudes and duration). Different aspect ratios will be used to model the two streams of polymerisations.

High viscosity extrusion grade PA6 and synthetic G of less than 2 µm particle size were used as fillers. GNP and G are dried for 6 h in vacuum oven at 90°C. Prior to in situ polymerisation, probe sonication was applied to disperse fillers in molten ɛ-caprolactam, the PA6 monomer. Five carbon loadings were made, that is 5–25 Wt.% for G and 0.5–2.5 Wt.% for GNP composites. Two different sonification regimes were applied 20% sonication amplitude for 20 min (20/20) and 40% sonication amplitude for 10 min (40/10).

Better tensile properties were achieved using the 20/20 processing streams for both G and GNP. The G- and the GNP-based composites systems of the 20/20 processing stream had tensile modulus and yield strength retained or improved above the unfilled PA6 value. The highest modulus obtained in the 20/20 streams are 1,878 and 1,201 MPa, respectively, for GNP and G at the highest loading levels, while the 40/10 processing streams had 963 and 1,247 MPa, respectively, for the GNP and G.

To the best of the authors’ knowledge, nobody has ever used sonification amplitude to compare mechanical properties.

The purpose of this paper is to deal with the tribological study on the brake pads developed using various purity-based graphitized graphite.

This paper deals with developing copper-free brake pads by using graphite as a key lubricant produced using a graphitization process with purity percentages (85, 90 and 95%). The brake pads were developed using traditional manufacturing processes and evaluated for their physical, chemical, thermal and mechanical properties as per industrial standards. Fade and recovery characteristics were analyzed using a full-scale inertia brake dynamometer as per JASO-C-406. The scanning electron microscope was used to analyze the worn surfaces of the brake pads.

The testing findings reveal that the brake pads with 95% graphitized graphite showed better shear strength with good adhesion levels and lesser density, hardness, acetone extract value, loss on ignition and higher porosity. Effectiveness studies of brake pads with graphite (95% graphitized) showed better results at higher pressure speed conditions than others because of better plateau formation and adequate lubrication.

This paper discusses graphitized graphite of different purity influences brake pad's tribological performance by modifying tribo-films and reducing friction undulations.

Graphene, which has abundant availability in nature, is currently under research for its functional applications in the field of textiles. The sp² Hybridized 1-atom-thick planar sheet has been under consideration for its unique electrical, mechanical and thermal properties, but there exists a void for aggregated data on the findings of other co-functional properties attained by the material using graphene oxide (GO) finish. This paper aims to define the techniques of extraction of GO, method of its application on textile material followed by detailed evaluation of the differential functional properties achieved.

The methodology used to explain the multiple functionalities of GO finish have been carried out by starting with the chemistry of graphene and the isolation of GO from graphite, followed by the techniques for its application on the textile along with the study on the induced functional properties that may aid to increase its potential applications.

It has been observed that with the aid of optimization of GO finish, the finish in lieu with the conductive potentialities may further provide with many essential properties such as hydrophobicity, ultraviolet protection and antibacterial property.

The field of research on GO finish is naive and except few properties, many functionalities are still unexplored that may enable its smooth production, handling and expanding its area of application. The agglomeration of scattered findings on the achievable functional properties of GO on various textiles has been achieved in this paper.

The purpose of this paper is to report on the tribological properties of beef tallow grease and improvements therein through modification with special processing, polymeric compounds and additives.

Pure original beef tallow grease was used as a biological lubricating grease reference material for the tribological research. Beef tallow was modified and synthesized by adding special biological anti-oxidant additives, LZ anti-wear additives, waste polyethylene terephthalate (PET) polymer compounds and thermally processed graphite.

Rheometric measurements indicate that the beef tallow grease modification technology used in this study enables control of the synthesis process to produce lubricants with the required microstructure. Investigation results of the tribological properties of differently modified greases show that beef tallow synthesized with polymer additives efficiently operates together with anti-wear additives to reduce friction and wear. The grease compound with thermally processed graphite has good tribological properties at 300 N load levels. The critical load level of lubricating greases could be significantly increased through the use of anti-wear additives and thermally processed graphite.

Investigation results of the tribological properties of differently modified beef tallow greases show that beef tallow synthesized with polymer additives efficiently operates together with anti-wear additives to reduce friction and wear. The critical load level of lubricating beef tallow greases could be significantly increased using anti-wear additives and thermally processed graphite.