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Waste tires are known as "black pollution", which is difficult to degrade. The safe handling and recycling of waste tires have always been the focus of and difficulty for the global rubber industry. Pyrolysis can not only solve the problem of environmental pollution but also completely treat the waste tires and recover valuable pyrolysis products. This paper summarizes research progress on the pyrolysis of waste tires, including the pyrolysis mechanism; the important factors affecting the pyrolysis of waste tires (pyrolysis temperature and catalysts); and the composition, properties, and applications of the three kinds of pyrolysis products. The composition and yield of pyrolysis products can be regulated by pyrolysis temperature and catalysts, and pyrolysis products can be well used in many industrial occasions after different forms of post-treatment. [ABSTRACT FROM AUTHOR]

Studies show that the long-term operation of a rubber mixer results in wear at the end face of the mixer. End face wear increases the gap between the mixing chamber and the end face, resulting in leakage and a reduction in the mixing performance, affecting the final product's quality. Therefore, it is essential to investigate the wear of the metal face during the mixing process. The present study added aramid fibers to a rubber compound using a mechanical blender to obtain a composite material. Then, the influence of the aramid fibers on the metal friction and wear of the end face of the mixer was analyzed. This article introduces the concept of the wear ratio and explores the friction and wear of metals from the perspective of formulation technology for the first time. With the addition of aramid fibers, the proportion of abrasive wear of rubber on metal decreased, and the proportion of corrosive wear increased during the mixing process; however, when the addition of aramid fibers exceeded 3 phr, the balance of abrasive wear of rubber on metal increased and the proportion of corrosive wear decreased. It was found that aramid fibers have the property of friction reduction, which reduces the wear of the rubber blend on the metal. When the amount of aramid fibers added was 3 phr, the amount of abrasion of the rubber compound on the metal was the lowest. [ABSTRACT FROM AUTHOR]

GF/rubber composites have sound insulation characteristics, heat resistance, good corrosion resistance, and high mechanical strength. The compounding machine's long working hours will inevitably wear the metal on the end face of the compounding machine. The wear of the end face metal will increase the gap between the chamber and the end face, which will lead to material leakage, reduce the mixing effect, and eventually affect the performance of GF/rubber composites. To ensure the implementation of GF/rubber composites, it is necessary to study the frictional wear behavior of GF/rubber composites on metals. In this paper, the effect of blending rubber with different amounts of GF on the frictional wear of metal on the end face was analyzed from the perspective of the formulation process, and the ratio of corrosion wear and abrasive wear was calculated for the first time. [ABSTRACT FROM AUTHOR]

The continuous operation of essential refining equipment, internal mixers, leads to wear on their end faces, resulting in an increased gap between the mixer chamber and the end face. This, in turn, causes material leakage, reducing mixing efficiency and adversely impacting rubber performance. Therefore, investigating metal wear on the mixer's end face during the mixing process is essential. Scholars have introduced dynamic covalent bonds into rubber molecular chains, bestowing self-repairing capabilities upon the materials. This innovation has significant implications for extending rubber lifespan and lowering production costs. It involves adding methacrylic acid (MAA) and excess zinc oxide (ZnO) to construct an ionic crosslinking network, limiting covalent crosslinking of rubber molecules and enabling in-situ polymerization of MAA/ZnO, resulting in self-repairing properties. However, it is crucial to consider corrosive wear induced by MAA's strong acidity on metals. This study combines MAA, ZnO, and multi-walled carbon nanotubes (MWCNTs) through mechanical mixing to create a composite material called zinc methacrylate (ZDMA)/MWCNTs/rubber. The research investigates the in-situ synthesis mechanism of MAA and ZnO and the synergistic mechanism of ZDMA and MWCNTs. The study analyzes the impact of MWCNTs additive amount on the frictional wear of the internal mixer's metal end face. During the mixing process, ZDMA is grafted and polymerized onto rubber's macromolecular chains, forming ionic pairs with strong electrostatic interactions, creating a primarily reversible supramolecular network dominated by ion crosslinking. This ion crosslinking network, along with the three-dimensional mesh structure of MWCNTs, establishes a stable spatial structure within the rubber matrix. The study reveals that increasing the MWCNTs content to 3 phr reduces the aggregation of SiO 2 particles and ZDMA granules within the rubber matrix, resulting in reduced friction coefficients, roughness, and wear rates of the metal. However, exceeding 3 phr of MAA content leads to excessive MWCNT aggregation within the rubber matrix, increasing wear rates, roughness, and friction coefficients due to hindrance of rubber macromolecular chain crosslinking and reduced SiO 2 particle dispersion within the rubber matrix. These findings provide valuable insights into the dynamics of frictional wear in internal mixers. • Continuous mixer use erodes end faces, widens gaps, and hampers rubber performance. • Adding dynamic covalent bonds to rubber enhances self-repair, extending lifespan and cutting production costs. • MAA, ZnO, and MWCNTs create ZDMA/MWCNTs/rubber, studied for frictional wear impact. • Elevated MWCNTs levels (up to 3 phr) lower wear rates, roughness, and friction in rubber. • Excessive MAA (> 3 phr) increases wear, roughness, and friction by blocking crosslinking and reducing dispersion. [ABSTRACT FROM AUTHOR]

Studies show that the dispersion of silica in the mixing process is an important factor affecting the wear of the mixing chamber. As the most important mixing equipment, the long operational life of the internal mixer will cause wear in the rotor and chamber of the internal mixer. This wear increases the gap between the rotor and chamber of the internal mixer, reduces the mixing performance, weakens the dispersion of packing, and adversely affects the quality of the rubber produced. Therefore, it is important to investigate the metal wear in the mixing process. This article examines the effect of the addition of different amounts of silane coupling agents on metal friction and wear during the mixing process. The silane coupling agent has two functions. The first is to make the surface of the silica hydrophobic, enabling it to combine the inorganic matrix of the silica with the organic matrix of the rubber; the second is to inhibit the aggregation of the silica in the rubber. In the present study, we examine (1) the influence of different formulations on the friction and wear of the metal in the mixing chamber from the perspective of formulation technology, and (2) the correlation between corrosion wear and abrasive wear. It is found that a rubber compound with 6 phr of TESPT has the lowest metal wear and that adding more TESPT does not affect the degree of metal wear. As the amount of TESPT increases, the proportion of abrasive wear decreases, while the proportion of corrosive wear increases, reaching a maximum of 20.7%. In our study we found that abrasive wear is the predominant wear mechanism of a rubber compound on metal. In contrast, the corrosive wear caused by high-temperature water vapor still occupies a large proportion of the total wear. Therefore, improving silica dispersion and reducing abrasive wear are extremely important methods to protect the mixing chamber. However, the corrosion of metals by high-temperature water vapor should also be considered when preparing for the mixing process. [ABSTRACT FROM AUTHOR]

Studies show that long‐term operation of the rubber mixer results in wear at the end face of the mixer. End face wear increases the gap between the mixing chamber and the end face, which results in leakage and reduces the mixing performance, thereby affecting the quality of the final product. Therefore, it is of significant importance to investigate the wear of metal face during the mixing process. In the present study, calcium powder was added to the rubber compound using a mechanical blender to obtain a composite material. Then the influence of the calcium powder on metal friction and wear of the end face of the mixer was analyzed. The obtained results show that the calcium powder has anti‐friction properties, which can greatly reduce the compound wear on the metal. The lowest corrosion and wear of the compound on the metal was achieved with 5 phr of calcium powder. Meanwhile, it is found that the tensile and tear‐resistance properties of the compound with 5 phr of calcium powder are slightly lower than those without calcium powder. However, the compound with 5 phr of calcium powder has higher friction, cold resistance, wet slip resistance, and lower rolling resistance. [ABSTRACT FROM AUTHOR]

During the blending process, the choice of lubricant used in the internal mixer significantly affects the properties of composite materials. This study thoroughly investigates the mechanisms that enhance the mechanical properties and anti-wear characteristics of Natural Rubber/ Butadiene Rubber/Solution-Polymerized Styrene Butadiene Rubber composite materials by employing both commonly used lubricants and graphene-based lubricant mediums. The research offers data-driven insights to enhance material performance during internal mixer blending and protect the end-face metals. The incorporation of graphene as a lubricant additive results in its deposition on friction pair surfaces, forming a protective anti-wear layer that prevents direct contact between the friction pairs and effectively reduces wear. Throughout the blending process, the composite materials inevitably come into contact with the lubricant. This research reveals that the addition of lubricant improves the dispersion of SiO 2 particles while reducing aggregate formation. Consequently, the SiO 2 particles-TESPT-rubber crosslinking network becomes denser, significantly enhancing the performance of Natural Rubber/ Butadiene Rubber/Solution-Polymerized Styrene Butadiene Rubber composite materials. Specifically, when using commonly used lubricant mediums, the material's hardness, tensile strength, and tear strength increase by 0.88 %, 7.8 %, and 4.5 %, respectively. In contrast, under the graphene lubricant medium, these properties improve by 2.7 %, 16.8 %, and 24.9 %, respectively. Notably, Natural Rubber/ Butadiene Rubber/Solution-Polymerized Styrene Butadiene Rubber composite materials using the graphene lubricant medium experience substantial reductions in rolling resistance and improved anti-wet skid performance. When comparing Natural Rubber/ Butadiene Rubber/Solution-Polymerized Styrene Butadiene Rubber composite materials with and without lubricants, composites prepared with both commonly used lubricants and graphene lubricants show significant reductions in metal wear and changes in metal surface roughness. Metal wear decreases by 17.5 % and 28.7 %, respectively, while changes in metal surface roughness are reduced by 46.3 % and 68.7 %, respectively. • Choice of lubricant affects composite properties in blending. • Lubricants enhance SiO 2 dispersion, densifying networks, boosting properties. • Lubricants notably reduce metal wear, graphene ones most effective. [ABSTRACT FROM AUTHOR]

During prolonged operation, the end face of the internal mixer, a crucial component in rubber processing, experiences wear, resulting in an increased gap between the mixing chamber and the end face. This gap can lead to material leakage and reduced mixing efficiency, negatively impacting rubber properties. To address this issue, researchers have introduced dynamic covalent bonds into the molecular rubber chains, giving the material self-healing properties. This advancement is essential for extending rubber lifespan and reducing production costs. One common approach involves adding methacrylic acid (MAA) and excess zinc oxide (ZnO) to create ionic crosslinking networks, limiting covalent crosslinking and enabling in-situ polymerization of MAA/ZnO, resulting in self-healing capabilities. However, the strong acidity and corrosive nature of MAA can cause metal wear. In our study, we mechanically blend MAA with ZnO to produce zinc methacrylate (ZDMA)/rubber composites. We investigate the in-situ synthesis mechanism of MAA and ZnO and assess the impact of MAA on the friction and wear of the internal mixer's end face. Our findings reveal that ZDMA ion pairs form an "ion cross-linked network" within the rubber chain, hindering SiO 2 particle dispersion and increasing aggregation within the rubber matrix. This compromises dispersion and leads to abrasive wear from SiO 2 particles, corrosive wear from high-temperature water vapor, and corrosive wear from MAA. Additionally, excessive ZDMA self-polymerization alters SiO 2 particle agglomerates. The strong acidity of MAA and the "ion cross-linked network" within the rubber matrix significantly affect SiO 2 particle dispersion, friction coefficients, metal surface roughness, and metal wear. Our comprehensive analysis, including SEM, dispersion, RPA, metal surface morphology, and CSM friction wear tests, identifies the optimal cross-linking effect with the addition of 15 phr of MAA, resulting in a well-defined "ion cross-linked network" within the rubber matrix, enhancing rubber performance. However, SiO 2 particle dispersion is compromised, leading to increased agglomeration and heightened metal wear. • Prolonged operation of internal mixers causes wear, increasing the gap, impacting rubber quality. • Self-healing rubber with dynamic covalent bonds extends lifespan and reduces costs. • A method involving MAA and ZnO for self-healing, but MAA's acidity causes metal wear. • Blending MAA and ZnO into ZDMA/rubber composites affects dispersion and wear. • An optimal MAA amount enhances rubber performance but compromises SiO 2 dispersion and increases metal wear. [ABSTRACT FROM AUTHOR]

Internal mixer is an important mixing equipment. After working for a long time, the end face of the internal mixer will be worn. The abrasion of the end face can increase the gap between the mixing chamber and the end face, and then material leakage occurs, which reduces the mixing effect and affects the performance of rubber compound. Therefore, it is very necessary to study the wear of the end face in the mixing process. As one‐dimensional nanomaterial, carbon nanotubes (CNTs) have a perfect hexagonal structure and many unusual mechanical, electrical and chemical properties. In recent years, with the deepening of the research of CNTs and nanomaterial's, their broad application prospects have also been continuously revealed. This paper analyzes the influence of rubber compounds with different CNTs content on the friction and wear of the end face from the perspective of formulation, and the correlation between corrosive wear and abrasive wear is studied. In the present study, it is found that as CNTs increase, the proportion of abrasive wear increases, the proportion of corrosive wear decreases, and the amount of the metal wear decreases. With the increase of CNTs, the hindering effect of CNTs on SiO2 molecules is strengthened, the degree of silanization reaction is reduced, the output of high‐temperature water vapor is reduced, and the corrosive wear of the metal is reduced. The spatial structure of CNTs is a cylinder with hexagonal plane, and it has extremely high toughness and softness, so it has slight wear on the metal. On the one hand, CNTs hinder the movement of SiO2 molecules. On the other hand, because CNTs have the wrapping effect on SiO2 molecules, some silica aggregates have no direct contact with the metal, CNTs become the medium for silica aggregates to contact with the metal. Therefore, with the increase of CNTs, the proportion of abrasive wear gradually increases, but the total amount of the metal wear gradually decreases. [ABSTRACT FROM AUTHOR]

Internal mixer is one the most commonly used rubber‐mixing equipment, which has been applied for decades. This device can operate continuously for a long time. Accordingly, it is quite probable to have wear of the end face of the mixer. Studies show that the end face wear increases the gap between the mixing chamber and the end face, resulting in material leakage, reducing the mixing effect and ultimately affecting the properties of the compound. Therefore, it is of significant importance to study the friction and wear of the mixing compound to the metal in the mixing process. Considering the superior characteristics of graphene (GE), it is considered a revolutionary material and has been widely applied in numerous applications. In the present study, the influence of the mixing compound with different amounts of GE on the friction and wear of the metal end face was analyzed and the ratio of the corrosion wear to abrasive wear was calculated for the first time. It was found that as the amount of GE increases, the proportion of abrasive wear on the metal increases, the proportion of corrosive wear on the metal decreases, and the metal wear decreases first and then increases. Moreover, the lowest metal wear can be achieved when the amount of GE is 3 phr. [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]

Perhydropolysilazane (PHPS) is an inorganic polymer composed of -(SiH 2 –NH)- repeating structural units. When used as a coating material, it has the advantages of good solubility, simple curing conditions, flexible curing process, and simple preparation method and can significantly save processing time and cost. This paper investigates the frictional behavior of the PHPS-coated metals cured at different temperatures with NR/BR/SBR composites. The effects of different curing temperatures on the PHPS coatings are characterized using infrared absorption spectroscopy. After curing, the asymmetric stretching and oscillating vibration peaks of the Si–O–Si groups are formed, which is attributed to the hydrolysis reaction of Si–N and Si–H and the subsequent cross-linking curing reaction. The denseness of PHPS coatings increases with the increase in curing temperature. When the curing temperature is 400 °C, the cross-linking curing effect of PHPS is the strongest, and the denseness of the PHPS coating is the best. Furtherly, the frictional wear of metal with NR/BR/SBR composites is analyzed from the perspective of the formulation process for the first time, and the ratio of abrasive wear and corrosion wear is calculated qualitatively. It is found that increasing the curing temperature of the PHPS coating can significantly reduce metal wear and improve corrosion resistance, which is attributed to the formation of the ethanol-water molecular film on the surface of the PHPS coating. The ethanol-water molecular film isolates the contact between the PHPS-coated metal and the NR/BR/SBR composite to a certain extent, acting as a lubricant and thus reducing friction. After rubbing the cured PHPS-coated metal with NR/BR/SBR composite, the wear amounts of the cured PHPS-coated metal at 200 °C, 300 °C, and 400 °C are reduced by 49.06%, 66.74%, and 87.33%, respectively, and the corrosion resistance are improved by 51.52%, 63.64%, and 78.79%, respectively. • The friction behaviour of silicone-coated metal and rubber composites cured at different temperatures was investigated. • The metal wear of the coating cured at 300℃ is reduced by 66.74%, and the corrosion resistance is increased by 63.64%. • After curing at 400℃, the metal wear is reduced by 87.33%, and the corrosion resistance is increased by 78.79%. [ABSTRACT FROM AUTHOR]

• In this study, based on the viscoelastic solid theory of the rubber mixing process and the friction mechanism between rubber and metal, combined with the discrete element method, a dynamic simulation model for the wear of the synchronous quadrilateral rotor of an internal mixer is established. • The simulation results are compared under different mixing parameters. Analysis is performed, and a control experiment is set up to verify the feasibility of the discrete element software (EDEM) rotor wear dynamic simulation model. As the core component of an internal mixer, the rotor is subjected to friction from rubber and its filler during the mixing process, which causes the surface of the rotor to wear and can also affect the gap between the rotor edges as well as the gap between the rotor and the mixing chamber wall. The more significant the rotor wear, the larger the gap between the rotor ribs and the wall of the mixing chamber, which results in weaker shearing effect of the rotor on the rubber and even leads to uneven dispersion of filler in the rubber, eventually affecting the mixing effect and mixing quality of the glue. In this study, based on the viscoelastic solid theory of the rubber mixing process and the friction mechanism between rubber and metal, combined with the discrete element method, a dynamic simulation model for the wear of the synchronous quadrilateral rotor of an internal mixer is established. The simulations are performed in the EDEM software, and the results are analyzed and compared under different mixing parameters. Further, a control experiment is established to verify the feasibility of the proposed dynamic model for rotor wear. [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]

As an essential rubber mixing equipment in continuous production, an internal mixer should have a long service life while operating at high intensity. Studies show that at these severe operating conditions, end face wear of the internal mixer is inevitable. It is worth noting that the end face is an important part of the closed mixing chamber. The head of the rotor shaft is inserted into the copper ring of the sealing plate, the sealing plate and the mixing chamber are pressed together by bolts. There is a gap between the rotors and the mixing chamber. During the mixing process, the mixed rubber in the mixing chamber is in direct contact with the end face, the end face metal is frictional and abraded. Wear of the end face may result in a gap between the mixing chamber and the end face, leading to material leakage. As the leakage intensifies, the gap between the end face and the mixing chamber further increases, thereby forming negative feedback. This phenomenon not only affects the chemical composition of the rubber but also reduces the mixing efficiency and decreases the performance of the rubber compound. The end surface material is cobalt chromium molybdenum tungsten alloy. The alloy model is Stellite 6B. In the present study, the influence of different amounts of CF on the friction and wear of the end face is analyzed from the chemical composition perspective. Moreover, the ratio of corrosion wear to abrasive wear is calculated. The obtained results show that as the amount of CF in the compound increases, the proportion of the corrosive wear of the compound to the metal increases, while the proportion of abrasive wear decreases. The highest proportion of corrosive wear and the lowest amount of metal wear can be achieved for the CF amount of 9 phr. As the CF content in the composition increases, the ratio of the corrosive wear of the rubber compound to metal decreases, while the proportion of abrasive wear and the total amount of wear to metal increases. • Studies show that at these severe operating conditions, end seal wear of the internal mixer is inevitable. • This study analyzed the effect of different additions of CF on the friction and wear of the end seal. • The highest proportion of corrosive wear and the lowest amount of metal wear can be achieved for the CF amount of 9 phr. [ABSTRACT FROM AUTHOR]

Internal mixer is an important mixing component in industrial applications. Studies show that when a mixer operates for a long time, wear may appear at the end face of the internal mixer. On the other hand, abrasion of the end face increases the gap between the mixing chamber and the end face. Then, leakage occurs, which reduces the mixing effect and affects the rubber performance. Therefore, it is of significant importance to study the wear of the end face during the mixing process. Graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) have excellent electrical characteristics and thermal conductivity so that they have been widely used in various fields such as synthesized composite rubbers. GO and MWCNTs are mechanically blended into natural rubber to obtain GO/MWCNTs composite material. In the present study, the influence of the GO/MWCNTs ratio on the friction and wear of the end face of the internal mixer is analyzed. The obtained results show that MWCNTs and GO molecules interact to form a three-dimensional network structure, which has a greater impact on the degree of silica dispersion, silanization reaction, and metal wear. As the GO content increases, the average friction coefficient between rubber and metal, metal roughness, the proportion of abrasive wear, and the amount of metal wear gradually decrease. The lowest values can be achieved when the amount of added GO is set to 3 phr. When the GO in the mixture exceeds 3 phr, the friction coefficient between rubber and metal, and the metal roughness change, thereby affecting the proportion of abrasive wear and increasing the amount of metal wear in the mixing process. In this experiment, the amount of CNT that reduces GO aggregation is 6 phr. On the whole, when the ratio of GO/MWCNTs is 3/6, the synergistic effect of MWCNTs and GO molecules is maximized, the area of the three-dimensional network structure of GO/MWCNTs is the largest, the dispersibility of SiO 2 is the best, and the amount of wear of the composite material on the metal is the lowest. • In the present study, the influence of the GO/MWCNTs ratio on the friction and wear of the end face of the internal mixer is analyzed. • The obtained results show that MWCNTs and GO molecules interact to form a three-dimensional network structure. • It is concluded that the metal wear is minimized when the ratio of GO/MWCNTs in the GO/MWCNTs composite is set to 3/6. [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]

As the basic equipment in the rubber field, the internal mixer is suitable for long-term rubber mixing. For the continuous production of the factory, the wear of the internal mixer is a problem that cannot be ignored. This article mainly studies the wear of the end face of the internal mixer. The end face of the mixer is connected to the mixing chamber. With the increase in mixing time, the end face of the mixer is inevitably worn. The abrasion of the end face of the internal mixer causes the gap between the end face of the internal mixer and the mixing chamber to increase, and the materials in the mixing chamber leak out. This affects the ratio of materials and reduces the mixing effect. And with the increase in material leakage, the abrasion of the end face of the internal mixer is intensified, which eventually leads to a decrease in the compound's performance. BF is a pure natural inorganic non-metallic material. It has good high-temperature resistance, and high compressive strength can be used in various environments and is inexpensive and cost-effective. Based on this, BF is increasingly used in the rubber field. In this paper, the effect of adding different amounts of BF on the friction and wear of the end face of the internal mixer is studied, and the proportions of varying wear forms are distinguished for the first time. The study finds that with the increase of BF in the compound, the proportion of abrasive wear first decreased and then increased, the balance of corrosion wear first increased and then decreased, and the amount of metal wear first decreased and then increased. It is found that the lowest wear of the rubber compound on the metal can be achieved when the amount of BF reaches 10 phr. When the BF amount increases, the corresponding amount of metal wear increases. • With the increase of mixing time, the end face of the mixer is inevitably worn. • This paper studied the effect of different BF additions on the friction and wear of metals. • It is found that the lowest wear of the rubber compound on the metal can be achieved when the amount of BF reaches 10 phr. [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]

As a piece of high-intensity running equipment, the wear of an internal mixer determines the quality of rubber and its life. In general, the wear of an internal mixer is caused by the friction between the rubber and metal during the mixing process, and the most severe wear position is the end face of the equipment. In this paper, a mixture of multi-walled carbon nanotubes (MWCNTs) and carbon fibers (CFs) are added to rubber by mechanical compounding to obtain MWCNT/CF/carbon black (CB) composites. By investigating the synergistic mechanism of MWCNTs and CFs, we analyze the effect of the MWCNT/CF ratio on the frictional wear of metal on the end face of the internal mixer. At the microscopic level, MWCNTs and CFs form a spatial meshwork with CB particles through synergistic interactions. The CB particles can be adsorbed on the spatial meshwork to promote the dispersion of CB particles. In addition, the formation of oil film can be slowed down due to the spatial meshwork, which could hinder the spillage of aromatic oil. Meanwhile, the spatial meshwork serves as a physical isolation layer between the rubber and metal to reduce friction. Therefore, it dramatically impacts the dispersion degree of CB particles, the friction coefficient, the roughness of the surface, and the wear of metal. It shows that the synergistic effect of MWCNT/CF and CB particles is best when the CF content of the rubber matrix is 5 phr, showing the most stable spatial network structure, the best dispersion of CB particles, and minor wear on the end face of the internal mixer. [ABSTRACT FROM AUTHOR]

The mixer is the most widely used batch mixing equipment in the rubber industry. The rotor is a core component and has a great impact on the mixing effect of the equipment. The current rotor structure design is done empirically, being tightly dependent on practical experience. This paper proposes a method for optimizing the rotor structure by using optimization algorithms combined with numerical simulation technology. Using MATLAB software, a parametric design program for synchronous rotors and a set of optimization programs for the particle swarm optimization (PSO) algorithm were written. The global distribution index was used as the fitness function to optimize the synchronous rotor configuration. A comparative analysis of the rotors before and after optimization shows that the optimization process is feasible, and the results are reliable. This provides new ideas for the design and development of mixer rotors. [ABSTRACT FROM AUTHOR]