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Carbon nanofibers (CNFs) as new materials have been the focus of materials research, while being widely used in the processing of rubber composites. To solve the problem that CNFs are easy to agglomerate, the existing methods are mainly chemical modification of CNFs (complicated processing process), blending with fillers such as carbon nanotube (expensive material and high production cost ratio). In this study, we integrated the economics and processing methods, and used pyrolysis carbon black (CBp) and CNFs for blending to prepare rubber composites to solve the filler agglomeration problem. It was found that CBp and CNFs produce a synergistic effect, and the two are isolated from each other and in contact with each other, forming a more complete filler network inside the composite. Through the synergistic effect, the filler dispersion in the rubber becomes better and the performance of the composite is greatly improved. Compared with traditional filler blending, it is more economical and can save production costs to a great extent; compared with chemical modification, the process is simple and saves production time. The recycling of rubber products can be promoted through the mass use of CBp, which has a certain environmental protection effect. This study provides new ideas for polymer composite processing, and more experiments are needed later to verify the feasibility of this method. [ABSTRACT FROM AUTHOR]

The effects of wet mixing and traditional mixing on the properties of radial-orientation basalt fiber-reinforced rubber products were studied through experiments. The results show that compared with traditional mixing, the basalt fibers under the wet mixing conditions can more effectively enhance the physical and mechanical properties of composites. The properties of the composites, such as carbon black dispersion, filler dispersion, rolling resistance and wet-sliding resistance, were the best after the latex and carbon black were premixed and then mixed by a mixer. Through extrusion experiments with the developed short-fiber radial-orientation die, it can be found that the fluidity of composites after extrusion is enhanced. Through analysis utilizing an electron microscope, it is shown that when the BFs added with KH550 (3-Aminopropyltriethoxysilane) were modified by KH560 ((3-Glycidyloxypropyl)trimethoxysilane), the interface layers of BF (basalt fiber)–KH560–NR and BF–KH550–NR were formed, which improves the adhesion between BFs and the rubber matrix. Qualitative characterization experiments on the orientation direction of the vulcanized composites were carried out through the experiments; that is, the qualitative characterization experiments on the segmented cutting and vulcanization of the composites in the radial direction showed that the short-fiber radial-orientation die could greatly improve the radial orientation degree of the short fibers in the radial direction. After adding KH560, the performance of the composites reinforced by the short fibers was improved to a certain extent compared with those without KH560. By adding DZ (N,N-Dicyclohexyl-2-benzothiazolsulfene amide) and CTP(cytidine triphosphate disodium) into the vulcanization system, the curing process of compounds in mixing and extrusion was delayed and the scorching resistance of short-fiber-reinforced composites was enhanced. Under the same conditions, the properties of the compounds after extrusion were greatly improved compared with those without extrusion. [ABSTRACT FROM AUTHOR]

Carbon based materials with excellent conductivity such as conductive carbon black, graphene, and carbon nanotubes (CNTs) are often used in the preparation of conductive polymer composites. Pyrolysis carbon black, as a recycled material of waste rubber, can be used as a substitute for other carbon black in some fields, which can greatly reduce the production cost and promote reuse of used rubber. In this article, pyrolysis carbon black is mixed with CNT and added to natural rubber by mechanical blending method to get the composite material. The synergistic effect of pyrolysis carbon black and CNT, 3D network structure and formation of conductive network are investigated, and the properties of composites are analyzed. The results show that the 3D "grape cluster" network structure formed by the synergistic action of the pyrolysis carbon black and CNT, which led to the improvement of the curing properties and mechanical properties of the composites, increase the Payne effect, decrease the dispersion of the filler, and significant reduction the volume resistivity of the composites. With the increasing of CNT content, the variation of the properties of the composites changed and stabilized. In general, when 40 phr pyrolysis carbon black and 4 phr CNT are mixed into rubber matrix, the composite has the best comprehensive performance, and the volume resistivity is 9.25E5. Our results provide new thoughts in preparing natural rubber conductive composites. By adding highly CNT and inexpensive pyrolysis carbon black, the problem of easy aggregation of a single filler is overcome, which is more economical than adding two highly conductive fillers, and the process is simpler and time‐saving compared to the modified solution. More studies need to be done in order to reveal the effects of pyrolysis carbon black in practical conductive composites. [ABSTRACT FROM AUTHOR]

Internal mixers play a critical role as blending equipment in the rubber industry, operating for extended hours under high intensity. Investigating the wear patterns of internal mixers holds paramount importance in curbing dust leakage and prolonging their operational lifespan during the mixing process. Thermal cracked carbon black (CBp), an economically viable material derived from waste rubber, stands as a potential substitute for other carbon blacks in specific applications. This substitution aids in waste rubber recycling, thereby promoting ecological sustainability. This study centers on the amalgamation of CBp and graphene oxide (GO) in varying proportions, incorporated into the rubber matrix via mechanical blending. The objective is to produce composite materials, namely CBp/GO/NR, and comprehend the synergistic mechanisms between CBp and GO. Furthermore, the study analyzes the impacts of different CBp/GO ratios on metal friction and wear at the internal mixer's end faces. Scanning electron microscopy (SEM) observations divulge a collaborative behavior between GO and CBp particles within the rubber matrix, culminating in a spatial "honeycomb" network structure. On one hand, GO's two-dimensional planar network structure aids in CBp particle dispersion. Conversely, this planar network restricts the overflow of aromatic oils in CBp particles, influencing oil film formation on the rubber surface. Simultaneously, the planar network of GO creates a physical isolation layer between the rubber and the metal components. The inclusion of GO in the rubber matrix introduces notable alterations in CBp particle dispersion, friction coefficient, metal surface roughness, and metal wear. In summary, the optimum interaction between GO and CBp particles is achieved when the GO content in the composite material reaches 4 phr. This interaction leads to superior CBp particle dispersion and minimal metal wear in the composite material. • Produce CBp/GO/NR composites, understand CBp and GO synergy. • Analyze CBp/GO ratios on metal friction/wear at mixer faces. • SEM shows collaborative GO and CBp behavior, "honeycomb" structure. • Optimal GO-CBp interaction at 4 phr in composite material. [ABSTRACT FROM AUTHOR]

As the essential mixing equipment, long hours of work can cause wear and tear on the end face of the compactor. The wear of the end faces leads to an increase in the gap between the chamber and the end faces, which leads to leakage, reduces the mixing effect, and ultimately affects the rubber properties. Therefore, it is necessary to study the end face metal wear during the mixing process. Thermally cracked carbon black, as recycled material for scrap rubber, can be used as a substitute for other carbon blacks in some fields, vastly reducing the production cost and promoting the reuse of scrap rubber. In this paper, thermally cracked carbon black (CBp) was mixed with multi-walled carbon nanotubes (MWCNTs) and added rubber by mechanical blending to obtain CBp/MWCNTs composites. The synergistic mechanism of CBp and MWCNTs was investigated to analyze the effect of CBp/MWCNTs ratios on the frictional wear of metal on the end face of the compactor. The results showed that MWCNTs cooperated with CBp particles to form a three-dimensional "grape bunch" network structure. On the one hand, the three-dimensional "grape bunch" network structure can adsorb CBp particles to promote the dispersion of CBp particles. On the other hand, the three-dimensional "grape bunch" network structure can also hinder the overflow of aromatic oil and affect oil film formation. At the same time, the three-dimensional "grape bunch" network structure can also form a physical isolation layer between the rubber and the metal. This significantly influences the degree of CBp particle dispersion, friction coefficient, metal surface roughness, and metal wear. It seems that the synergistic effect between MWCNTs and CBp particles is maximized when the content of MWCNTs in CBp/MWCNTs composites is 4 phr, the area of CBp/MWCNTs three-dimensional mesh is maximized, the dispersion of CBp particles is the best, and the wear of CBp/MWCNTs composites on metal is the lowest. • As the essential mixing equipment, long hours of work can cause wear and tear on the end face of the compactor. • The effect of the synergistic effect of CBp and MWCNTs on the friction and wear of end-face metal was analyzed. • The results showed that MWCNTs cooperated with CBp particles to form a three-dimensional "grape bunch" network structure. [ABSTRACT FROM AUTHOR]

The gap between the rotor and the mixer chamber wall is an important factor in determining filler dispersion in rubber compounds. The inner wall of a mixer will wear after working for a long time, which will cause poor filler dispersion and affect the quality of rubber products. In this study, MoDTC was added to carbon black as a kind of filler, and the effect on filler dispersion, the properties of the rubber product, and the friction and wear of rubber and metal in the mixing process were examined. Experimental data showed that after adding 3 phr of MoDTC, carbon black dispersion was greatly improved, the curing time was shortened, and the performance remained stable. It was also found that the Mo element of the compound with 3 phr MoDTC dispersed better than that of the other compounds. Most importantly, adding 3 phr of MoDTC greatly reduced the amount of wear on the metal during the mixing process. However, the opposite effect occurred when the MoDTC content was high. The method proposed in this study can not only improve filler dispersion in rubber but also reduce metal wear to prolong the service life of the mixing chamber when applied to an actual mixing process. [ABSTRACT FROM AUTHOR]