Natural rubber composites carbon black

Zhou et al. [12] fabricated an extremely durable superhydrophobic tridecafluorooctyl triethoxysilane modified poly(dimethylsiloxane) (PDMS)/silica nanoparticle composite coating for use on different fabrics (Figure 10.5). Inspiration for the robust composite coating was obtained from a tire, a classic and highly durable nanocomposite material, where the main components are natural rubber and carbon black. 

This is Volume 2 of Natural Rubber Materials and it covers natural rubber-based composites and nanocomposites in 27 chapters. It focuses on the different types of fillers, the filler matrix reinforcement mechanisms, manufacturing techniques, and applications of natural rubber-based composites and nanocomposites. The first 4 chapters deal with the present state of art and manufacturing methods of natural rubber materials. Two of these chapters explain the theory of reinforcement and the various reinforcing nanofillers in natural rubber. Chapters 5 to 19 detail the natural rubber composites and nanocomposites with various fillers sueh as siliea, glass fibre, metal oxides, carbon black, clay, POSS and natural fibres ete. Chapters 20-26 discuss the major characterisation techniques and the final ehapter covers the applications of natural rubber composites and nanoeomposites. By covering recent developments as well as the future uses of rubber, this volume will be a standard reference for scientists and researchers in the field of polymer chemistry for many years to come. 

A common practice to enhance the properties of rubber products is by loading large amounts of fillers that are either reinforcing or non-reinforcing. Traditionally carbon black, precipitated silica and calcium carbonate are used to reinforce the natural rubber matrix in bulk amounts, up to 80 phr in some cases. Addition of large quantities of fillers reduces the elasticity and processability and increases the weight of the natural rubber composites. 

In this work [91], the effects of the quality of carbon black dispersion on the dynamic shear moduli of uncured, carbon-black-filled, natural rubber compositions were investigated. Effects due to changes in temperature,... 

Imoisili PE, Ukoba KO, Adejugbe T, Adgidzi D, Olusunle SOO (2013) Mechanical properties of rice husk/carbon black hybrid natural rubber composite. Chem Mater Res 3(8) 12... 

GRT particles are also compositionally quite complex. Tires contain a number of different rubbers (SBR, butyl rubber, natural rubber, polybutadiene rubber etc.), carbon black filler, antioxidants, and additional additives, the exact composition depending on the t3q)e of tire and the part of the tire (e.g. tread vs. side-wall, vs. liner). Elementally, a t3q)ical tire is comprised of carbon 83%, hydrogen 7%, ash 6%, oxygen 2.5%, sulfur 1.2%, and nitrogen 0.3%. There is approximately 45-55% rubber hydrocarbon, 10-15% acetone extractables, 20-30% carbon black, and 6% ash. ... 

Choi, S.-S., C. Nab, and B.-W. Jo, Properties of natural rubber composites reinforced with silica or carbon black Influence of cure accelerator content and filler dispersion. Polymer International, 2003. 52(8) 1382-1389. 

The pneumatic tire has the geometry of a thin-wallcd toroidal shell. It consists of as many as fifty different materials, including natural rubber and a variety ot synthetic elastomers, plus carbon black of various types, tire cord, bead wire, and many chemical compounding ingredients, such as sulfur and zinc oxide. These constituent materials are combined in different proportions to form the key components of the composite tire structure. The compliant tread of a passenger car tire, for example, provides road grip the sidewall protects the internal cords from curb abrasion in turn, the cords, prestressed by inflation pressure, reinforce the rubber matrix and carry the majority of applied loads finally, the two circumferential bundles of bead wire anchor the pressnrized torus securely to the rim of the wheel. 

Polysaccharides such as starch and cellulose have been used as reinforcing agents in natural rubber. Both solution blending and dry mixing methods have been employed for the development of biocomposites and the performance compared with the composites obtained using carbon black. Dry mixing method is more economically viable and environment friendly. 

Generally speaking, commercial rubber products are manufactured as a composite from a rubber and a nano-filler, which is in a group of fillers of nanometer size (mainly, carbon black and particulate silica). For an example, a pneumatic tire for heavy-duty usages such as aircrafts and heavyweight tracks is made from natural rubber (NR) and carbon black and/or silica. Their reinforcing ability onto rubbers makes them an indispensable component in the rubber products [1,2]. 

Tires are one of the most durable technological products manufactured today. They are a resilient, durable composite of fabric, steel, carbon black, natural rubber, and synthetic polymers. The qualities that make tires or other engineered rubber products a high-value item create a special challenge of disposal. Tires and other rubber products, such as conveyor belts and hydrauUc hoses, are not biodegradable and cannot be recycled like glass, aluminum, or plastic. Four potential applications for such products entering the solid waste stream have been identified ... 

The example chosen here to illustrate this type of composite involves a polymeric phase that exhibits rubberlike elasticity. This application is of considerable practical importance since elastomers, particularly those which cannot undergo strain-induced crystallization, are generally compounded with a reinforcing filler. The two most important examples are the addition of carbon black to natural rubber and to some synthetic elastomers and silica to polysiloxane elastomers. The advantages obtained include improved abrasion resistance, tear strength, and tensile strength. Disadvantages include increases in hysteresis (and thus heat buUd-up) and compression set (permanent deformation). 

NR composites and nanocomposites can be fabricated by three main techniques, namely latex compounding, solution mixing and melt blending. A variety of nanofillers, such as carbon black, silica, carbon nanotubes, graphene, calcium carbonate, organomodified clay, reclaimed rubber powder, recycled poly(ethylene terephthalate) powder, cellulose whiskers, starch nanocrystals, etc. have been used to reinforce NR composites and nanocomposites over the past two decades. In this chapter, we discuss the preparation and properties of NR composites and nanocomposites from the viewpoint of nanofillers. We divide nanofillers into four different types conventional fillers, natural fillers, metal or compound fillers and hybrid fillers, and the following discussion is based on this classification. 

In this chapter, ESR studies on NR composites and nanocomposites are extensively reviewed based on available published literatures. A very few ESR studies on rubbers were conducted due its complexity and specific natures. Interactions between both carbon black and silica particles with NR matrix were well established by conducting the ESR study. Variations of the ESR spectra and the concentration of the unpaired spins of NR/carbon black composites with carbon black concentration, milling time, types of carbon... 

Volnme resistivities have been reported on phenol-formaldehyde [37], carbon fibre reinforced ABS terpolymer [35], natural rubber [38], polystyrene (PS) [35], HDPE-natnral fibre composites [34], carbon black filled PP-epoxy-glass fibre composites [5], XLPE [32], nanoclay reinforced EPDM-g-TMEVS [31] and epoxy resin/PANI blends [33]. 

Thin films of blended deuterated polystyrene (dPS) and poly(vinyl methyl ether) (PVME) were imaged as a fimction of the dPS PVME ratio. Near the critical composition of 35% dPS, an imdulating, spinodal-like structure was observed, whereas for compositions away from the critical mixture ratio, regular mounds or holes (< dPS < < crit and < dPS > (pent, respectively) were present. These variations were assigned to surface tension effects (120). Blends of PBD, SBR, isobutylene-brominated p-methylstyrene, PP, PE, natural rubber, and isoprene-styrene-isoprene block rubbers were imaged (Fig. 18). Stiff, styrenic phases and rubbery core-shell phases were evident as the authors utilized force-modulated afm to determine detailed microstructure of blends, including those with fillers such as carbon-black and silica (121). 

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