CO2 intensive carbon black (CB) as filler material in natural Hevea rubber-based composites needs to be partially replaced by suitable fillers. In this study, a novel surface modified filler (SuMo ...FA) was made by encapsulating fly ash (FA) with a polysulphide coating. This SuMo FA was hydrophobic, minimized leaching, and was morphologically ideal as partial replacement filler of CB in Hevea rubber-based composites. This SuMO fly ash and unmodified FA was compounded from 5, 10 and 20 parts per hundred rubber (phr) accounting for partial substitution of CB at 5, 10, 20 and 40 (by weight (wt%)), respectively. The tensile properties and Shore A hardness were practically unchanged with unmodified FA at 5 wt% CB replacement. SuMo FA performed better, retaining tensile properties up to 20 wt% CB replacement. Major decreases were seen only at 40 wt% CB replacement. Chemical crosslink densities decreased somewhat with increasing ash content, while thermal stability remained constant. The encapsulation reduced the leachability of toxic heavy metals from SuMo FA to below United States-Environmental Protection Agency limits opening up the use of such composites in consumer markets in addition to industrial ones. Thus, SuMo FA is a promising waste-derived filler that can be used to partially replace carbon black in rubber composites without loss of mechanical properties or thermal stability.
•Novel surface modified filler (SuMo FA) was made.•The tensile properties and Shore A hardness were practically unchanged for SuMo FA•SuMo FA can partially replace carbon black in rubber composites•The encapsulation reduced leachability of toxic heavy metals from SuMo FA
Decades of researches have proved that pyrolysis can not only realize the harmless disposal of waste tire, but also carry out the goal of waste resource utilization via recycling pyrolytic products ...(e.g. pyrolytic carbon black, CBp). The current work studied the effect of CBp obtained from the commercial scale pyrolysis of waste tire, on the properties of natural rubber and butadiene rubber. CBp was incorporated into a carbon black quality identification standard formula in combination with N234 commercial carbon black (cCB) first. After screening a better substitution ratio, the composite material of CBp and cCB was mixed with more additives, and the experiment was carried out with a real production formula. To restore the practical production situation, the experiment process adopts the most commonly used process to avoid major changes in commercial production. CBp was tested at increasing loading levels as partial or full replacement of cCB. The physico-mechanical properties of the rubber compounds were studied by tests of physical, mechanical, and vulcanization properties. With the increase in the amount of CBp added, the physical and mechanical properties of the rubber compound showed a trend of slightly increasing first and then rapidly decreasing. The addition of CBp can increase the yield strength and stiffness of the rubber, but it may also lead to a decrease in hardness. Meanwhile, the substitution ratio of CBp up to 50% has been proven to improve safety and achieve a more stable vulcanization process of rubber compounds. CBp can replace up to half of cCB without significantly reducing the quality of tire rubber. The economic value of partial replacement of cCB by CBp has also been evaluated, demonstrating that adding a small amount of CBp can directly reduce the cost of raw materials, indirectly reduce the use of fossil energy promoting carbon dioxide reduction worldwide.
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•A commercial high-value application method of pyrolysis residual is explored.•Incorporation of carbon black obtained from waste tire in rubber matrix.•Pyrolytic carbon black can replace half of commercial one guaranteeing rubber quality.•Equipment and materials used are close to commercial production requirements.•Sales of waste tire pyrolysis products have been expanded.
Based on nonlinear viscoelastic theory and coupled thermo-mechanical approach, heat build-up analysis of a rubber specimen under cyclic loading was performed through finite element analysis. The ...determination of the rubber material properties attracted particular attention. The thermo-mechanical coupling approach can be divided into three major parts: deformation, dissipation, and thermal modules. In the deformation module, uniaxial, planar, and equibiaxial tensile tests were used to determine the hyperelastic constitutive equation. In the dissipation module, an analytical method for calculating the energy dissipation rate was established. The dynamic properties were updated as a function of the strain and temperature based on the modified Kraus model. Creep effect and dynamic property softening effect on the viscoelastic properties were firstly considered. In the thermal module, the dependence of thermal parameters on temperature was established. A highly sophisticated equipment which can measure the temperature rise curves both on the surface and at the heart of the rubber specimen was used to verify the calculated results. The comparison between numerical results and experimental data shows that the proposed analysis method provides a satisfactory way to predict heat build-up for rubber compounds.
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•Heat build-up analysis for rubber compounds was performed.•Thermo-mechanical coupling approach and nonlinear viscoelastic theory were used.•Creep effect on heat build-up for rubber compounds was firstly considered.•Dynamic property softening effect on heat build-up was firstly considered.•A highly sophisticated equipment was used to verify calculated temperature results.
A byproduct of the power generation industries, fly ash can be used as a potential filler in many commercial products including rubber-based products. Reusing the fly ash in this manner is an ...efficient way to help prevent air pollution which occurs if such particles are released freely to the atmosphere. The reinforcement efficiency of fly ash for partial replacement of carbon black and silica fillers in styrene-butadiene rubber compounds was investigated in this work. The total content of fillers was held constant at 50 phr (weight ratio of filler to rubber was 0.5) when not using silica fillers at all, and 54 phr when using 4 phr carbon black only with silica fillers, while the content of fly ash increased from 0 to 10 phr. In the evaluation of the rubber compounds, the focus was the mechanical properties and adhesion of steel reinforcement cords to the styrene-butadiene rubber compounds. Adhesion between the compounds and steel wire reinforcement was measured for assessing efficacy of adding fly ash to the rubber compounds in tire applications. Ball mill treatment was used to reduce the size of the fly ash particles while also modifying their surface topography. The comparisons of untreated and ball mill treated fly ash filled rubber compounds and rubber compounds containing different fillers were accomplished subsequently. The results revealed that the partial addition of up to 10 phr fly ash to rubber compounds resulted in increases in elongation at break, adhesion to reinforcement steel cord, wet-grip, as well as lower rolling resistance as attributed to more effective filler dispersion and the reinforcing effect of silica present in fly ash.
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•Fly ash is a byproduct of the fossil fuel power generation industries.•Fly ash can be an alternative to carbon black and silica in rubber products.•Fly ash reinforces styrene-butadiene rubber compounds.•Tensile, dynamic mechanical and adhesive properties are improved by addition of fly ash.
In the many countries the main strategy for waste tires utilization is still energy recovery, which use waste tires as low-cost and high-calorific alternative fuel. Although, energy recovery is step ...forward for suitable waste tires collection and management, it should not be considered as a green and environmentally-friendly method.
Waste tires recycling and upcycling technologies are crucial for further realization of circular economy strategies. Therefore, improvement of already existed and searching for new methods of waste tires industrial applications are fully justified.
In this work, recent advances in development of waste tire rubber-based materials characterized by high content of ground tire rubber (defined as minimum 70 wt%) are presented and discussed. A special attention was focused on the correlation between sustainable treatment or functionalization of waste tire rubber and the structure–property relationships of the prepared materials.
Moreover, the main problems and challenges affecting the possible industrial application of materials highly modified by waste tire rubber are also highlighted.
Abstract The crystalline cellulose has captured much attention as reinforcement material in rubber composites, but no successful cases have been found till now. Here, a facile approach of cellulose ...utilization was proposed by in‐situ regenerating cellulose in dry rubber matrix. Cellulose was dissolved in ionic liquid (IL), and then directly mixed with dry rubber, silica, and other ingredients. Taking advantages of the strong interaction between IL and silica, the dissolution equilibrium of cellulose/IL was destroyed and resulted in the regeneration of cellulose crystals in rubber matrix. The regenerated cellulose appeared at dry blending stage, and showed an ideal rod‐like shape (10–100 nm in diameter and 200–500 nm in length). While it grew in size at curing stage, and finally reached 100–200 nm in diameter and 1–2 μm in length. The regenerated cellulose exhibited pronounced reinforcement efficiency. This methodology has no any waste liquid discharged, and has a promising use in the preparation of cellulose/rubber composites. Highlights Nanosized rod‐like cellulose was regenerated in dry rubber, instead of latex. Regeneration of cellulose was due to interaction between ionic liquid and silica. The in situ regenerated cellulose dispersed well in cured rubber compounds. The regenerated cellulose exhibited a good reinforcement efficiency in rubber. The whole machining process had no any waste liquid discharged.
•The microcrystalline cellulose was hybridized with nano-ZnO using microreactor.•The morphologies of ZnO can be sphere, rod or tube by controlling the microreactor.•The MCC-ZnO filler can be used ...successfully in tire tread compounds.
Microcrystalline cellulose (MCC) was first swollen and then hybridized with nano-ZnO to prepare MCC-ZnO hybrid composites using a microreactor technique. The microstructure of the ZnO particles was controlled and characterized. The results showed that the nano-ZnO particles had a Wurtzite structure and were successfully loaded on the surface of the MCC, and the ZnO morphologies could be shaped as spheres, rods or tubes by controlling the size of microreactor. The hybrid ratio of ZnO was approximately 20%. The MCC-ZnO hybrids were used in SSBR2557A/SiO2 compounds to replace portions of the silica. The results showed that MCC-ZnO compounds had improved processing and mechanical properties compared to the pure MCC sample. The dynamic mechanical analysis (DMA) indicated that MCC-ZnO compounds had higher wet-skid resistance and lower rolling resistance than the control samples. The interfacial bonding between the hybrids and rubber was also improved; the sizes of the hybrid composites decreased in situ during the rubber processing.
Tire performance plays a significant role in vehicles’ safety and fuel efficiency and is thus a critical vehicle technology driven by the materials used. The tires’ characteristics are largely ...dependent on the properties of the tread rubber compound, which are significantly affected by the type and amount of fillers used for static and dynamic reinforcement. In this work, a silane coupling agent was used to functionalize aramid nanofibers (ANFs), and the effect of a carbon black/ANF hybrid filler on the properties of tire tread rubber compounds was investigated. A functionalized ANF/water paste mixture was prepared and uniformly dispersed in the conventional dry rubber without using a solution mixing method, therefore avoiding latex co-coagulation, and the uniform dispersion of ANFs in the rubber matrix was confirmed through scanning electron microscopy. The properties of the carbon black/ANF hybrid filler reinforced rubber compounds at various weight fractions were then evaluated using tensile testing, dynamic mechanical analysis, and abrasion resistance testing. The rolling resistance and abrasion resistance of rubber compounds with 1 part of ANFs were found to improve over the baseline neat rubber samples by 14.7 and 11.3%, respectively, all while maintaining the wet skid resistance. Thus, this study establishes that the addition of ANFs in the tread rubber compound enhances the tires’ overall performance requirements, known as the “magic triangle.”
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