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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.

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.

The purpose of this paper is to present the modeling of statistical variation of experimental data using the design of experiments method to optimize the formulation of a high performance concrete (HPC) using materials that are locally available in Algeria. For this, two mineral additions (natural pozzolana and limestone filler [LF]) were used. Both additions are added by substitution of cement up to 25%. To better appreciate the effect of replacing a part of cement by natural pozzolana and LF and to optimize their combined effect on the characteristics of HPC, an effective analytical method is therefore needed to reach the required objective.

The experimental part of the study consisted of substituting a portion of cement by various proportions of these additions to assess their effects on the physico-mechanical characteristics of HPC. A mixture design with three factors and five levels was carried out. The JMP7 software was used to provide mathematical models for the statistical variation of measured values and to perform a statistical analysis. These models made it possible to show the contribution of the three factors and their interactions in the variation of the response.

The mixture design approach made it possible to visualize the influence of LF and pozzolanic filler (PF) on the physico-mechanical characteristics of HPC, the developed models present good correlation coefficients (R² = 0.82) for all studied responses. The obtained results indicated that it is quite possible to substitute a part of cement with LF and PF in the formulation of a HPC. Thanks to the complementary effect between the two additions, the workability could be improved and the strengths drop could be avoided in the short, medium and long term. The optimization of mixture design factors based on the mathematical models was carried out to select the appropriate factors combinations; a good agreement between the experimental results and the predicted results was obtained.

The coefficient of PF in Cs₂₈ model is closer to that of LF than in Cs₇ model, thanks to the complementary effect between LF and PF at the age of 28 days. It was found that the optimal HPC14 concrete (10%LF–5%PF) provides the best compromise between the three responses. It is also worth noting that the use of these two local materials can reduce the manufacturing costs of HPC and reduce carbon dioxide emissions into the atmosphere. This can be an important economic and environmental alternative.

This paper aims to focus on the development of the three-dimensional (3D) printing filaments based on acrylonitrile butadiene styrene (ABS) copolymer and styrene-ethylene/butylene-styrene (SEBS) block copolymer, with tailored viscoelastic properties and controlled flow during the 3D printing process.

In this investigation, ABS was blended with various amounts of SEBS via a melt mixing process. Then the ABS/SEBS filaments were prepared by a single-screw extruder and printed by the FDM method. The rheological properties were determined using an MCR 501 from Anton-Paar. The melt flow behavior of ABS/SEBS filaments was determined. The morphology of the filaments was studied by scanning electron microscope and the mechanical (tensile and impact) properties, surface roughness and void content of printed samples were investigated.

The rheological results can accurately interpret what drives the morphology and mechanical properties’ changes in the blends. The impact strength, toughness, elongation-at-break and anisotropy in mechanical properties of ABS samples were improved concurrently by adding 40 Wt.% of SEBS. The optimal tensile properties of blend containing 40 Wt.% SEBS samples were obtained at −45°/+45° raster angle, 0.05 mm layer thickness and XYZ build orientation. Optimized samples showed an 890% increase in elongation compared to neat ABS. Also, the impact strength of ABS samples showed a 60% improvement by adding 40 Wt.% SEBS.

The paper simultaneously evaluates the effects of material composition and 3D printing parameters (layer thickness, raster angle and build orientation) on the rheology, morphology, mechanical properties and surface roughness. Also, a mechanical properties comparison between printed samples and their compression-molded counterpart was conducted.

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.

A suggestion that instead of retarding corrosion it might be a good idea to think of ways of accelerating it, was made by Dr Norbert Ibl, President of the Scientific Committee, at the opening ceremony of the 8th Congress of the International Union for Electrodeposition and Surface Finishing held recently in Basle.

A suggestion that instead of retarding corrosion it might be a good idea to think of ways of accelerating it, was made by Dr Norbert Ibl, President of the Scientific Committee, at the opening ceremony of the 8th Congress of the International Union for Electrodeposition and Surface Finishing held recently in Basle.

Corrosion of Steel by Sulphur: Although joints made with commercial plasticised sulphur cement, properly made, do not cause attack on iron or steel pipes, steel is attacked when immersed in aqueous dispersions of elementary sulphur. Further light was thrown on this phenomenon in recent tests with low‐carbon steel panels having an area slightly greater than 4 sq. in. and weighing approximately 16 g. These were essentially unaffected when completely immersed for seven days in tap water, distilled water or dispersions of bentonite in water, but weight losses as high as 1.87 g. were noted when immersed in dispersions of sulphur in water. In the absence of a dispersion agent, the weight loss of the test panels was 1.8 g., or 8.6%. In contrast, the weight loss was less than 0.25 g. when the specimens were immersed in 3% hydrochloric acid.

The first major nickel alloy introduced to the industry, about 100 years ago, was a Ni‐Cu alloy 400. This alloy is still widely used in a variety of industries and will continue to be used in this current century. Over the past 100 years, especially in the last 50 years, improvements in alloy metallurgy, melting technology, and thermo‐mechanical processing, along with a better fundamental understanding of the role of various alloying elements has led to new nickel alloys. These have not only extended the range of usefulness of existing alloys by overcoming their limitations, but are reliable and cost‐effective and have opened new areas of applications. This paper briefly describes the various nickel alloy systems developed during the last 100 years and comments on what the future holds for the newer alloys developed in the last 20 years and on the competition faced by these alloys in the new millennium. High‐temperature alloys are not discussed in this paper.

Observations on alloy tests. Rotating‐cantilever tests in air and corrosion‐fatigue tests have been made on a high‐purity aluminium‐zinc‐magnesium alloy and on a commercial alloy (D.T.D. 683) in various conditions of heat treatment. The results are compared with special reference to the form of fracture and microstructure. Evolution of gas from active slip zones under corrosion fatigue has been observed.