Styrene-butadiene rubber matrix

He, S.-J., Wang, Y.-Q., Xi, M.-M., Lin, J., Xue, Y., Zhang, L.-Q. Prevention of oxide aging acceleration by nano-dispersed clay in styrene-butadiene rubber matrix. Polym. Degrad. Stab. 98, 1773-1779 (2013)... 

In one of the first reports on fiber reinforcement of rubber, natural rubber (NR) was used by Collier [9] as the rubber matrix, which was reinforced using short cotton fibers. Some of the most commonly used rubber matrices for fiber reinforcement are NR, ethylene-propylene-diene monomer (EPDM) rubber, styrene-butadiene rubber (SBR), polychloroprene rubber, and nitrile rubber [10-13]. These rubbers were reinforced using short and long fibers including jute, silk, and rayon [14—16]. 

Although PFE lacks a proven total concept for in-polymer analysis, as in the case of closed-vessel MAE (though limited to polyolefins), a framework for method development and optimisation is now available which is expected to be an excellent guide for a wide variety of applications, including non-polyolefinic matrices. Already, reported results refer to HDPE, LDPE, LLDPE, PP, PA6, PA6.6, PET, PBT, PMMA, PS, PVC, ABS, styrene-butadiene rubbers, while others may be added, such as the determination of oil in EPDM, the quantification of the water-insoluble fraction in nylon, as well as the determination of the isotacticity of polypropylene and of heptane insolubles. Thus PFE seems to cover a much broader polymer matrix range than MAE and appears to be quite suitable for R D samples. 

Radiation vulcanization of carbon fiber reinforced styrene-butadiene rubber causes a substantial increase in crosslink density (Figure 11.4) and tensile strength (Figure 11.5). This magnitude of change is possible only when the interaction between the filler and the matrix is improved. When irradiated in the presence of air, carbon fibers gain functionality which substantially increases their adhesion resulting in a spectacular improvement in properties. SEM studies show that as the dose of radiation increases, the adhesion of the... 

Xanthates were also used for microencapsulation of pesticides the pesticide and a soluble xanthate were blended in aqueous solution followed by acidification and the addition of a coupling agent to form a matrix.2218-2227 Particles of nitrile-butadiene rubber (NBR) and styrene-butadiene rubber (SBR) were also encapsulated by starch xanthates.2228... 

Only types (l)-(4) fall within the scope of this chapter. No further reference will be made to emulsion-polymerized prolybutadiene rubbers, because they are now of little industrial significance relative to the styrene-butadiene rubbers. Poly(vinyl chloride) is discussed elsewhere in this book. Brief reference will also be made in this chapter (Section 15.5) to the production and properties of carboxylated variants of styrene-butadiene rubber latexes. It may also be noted that latexes of rubbery terpolymers of styrene, vinyl pyridine and butadiene, produced by emulsion polymerization, have long been of considerable industrial importance for the specialized application of treating textile fibres (e.g., tyre cords) in order to improve adhesion between the fibres and a matrix of vulcanized rubber in which they are subsequently to be embedded. 

Figure 9.1. Phase-contrast micrographs of blends of chloroprene (CR), nitrile rubber (NBR), ethylene-propylene terpolymer (EPDM), and chlorobutyl rubber with styrene-butadiene rubber (SBR). The SBR phase appears white for the blends with CR and NBR, and dark for the blends with EPDM and chlorobutyl rubber. At low concentrations, the admixed rubber is the dispersed phase at higher concentrations, a phase inversion occurs and the admixed rubber becomes the matrix. (Callan et al, 1971.)...

Sikdar et al. (2000) developed adsorbent-filled PV membranes for removing VOCs from waste water. These membranes were prepared by dispersing at least one hydrophobic adsorbent uniformly into a polymer matrix. Polymeric membrane was made of rubbery polymer selected from the group consisting of PDMSs, PTMSP, PUs, polycarbonates (PCs), PE-block-polyamides, silicon PCs, styrene butadiene rubber, nitrile butadiene rubber, and ethane-propene terpolymer. The hydrophobic adsorbent was selected from the group consisting of hydrophobic zeolites, hydrophobic molecular sieves, activated carbon, hydrophobic polymer resin adsorbents, and mixtures thereof. 

Mixtures, formulated blends, or copolymers usually provide distinctive pyrolysis fragments that enable qualitative and quantitative analysis of the components to be undertaken, e.g., natural rubber (isoprene, dipentene), butadiene rubber (butadiene, vinylcyclo-hexene), styrene-butadiene rubber (butadiene, vinyl-cyclohexene, styrene). Pyrolyses are performed at a temperature that maximizes the production of a characteristic fragment, perhaps following stepped pyrolysis for unknown samples, and components are quantified by comparison with a calibration graph from pure standards. Different yields of products from mixed homopolymers and from copolymers of similar constitution may be found owing to different thermal stabilities. Appropriate copolymers should thus be used as standards and mass balance should be assessed to allow for nonvolatile additives. The amount of polymer within a matrix (e.g., 0.5%... 

For hydrophobic elastomers such as NR and styrene butadiene rubber, carbon black usually has been selected as filler due to the hydrophobic surface characteristics and special particle shapes of carbon black which provide good dispersion. However, the dispersion of polar filler in hydro-phobic rubbers matrix is difficult because of its hydrophilic surface. The hydroxyl groups exist on the surface of polar filler provide strong filler-filler interactions which resulted in poor filler dispersion. The polar surface of filler formed hydrogen bonds with polar materials in a rubber compound. As known, the silica surface is acidic and forms strong hydrogen bonds with basic materials. ... 

Whatever the nature of the elastomer used as matrix, i.e. polyurethane, poly(ethylene-vinylacetate) or styrene-butadiene rubber (SBR), it appears that the interfacial shear strength x of carbon fibre-elastomer composites is much higher than theoretically expected from equation (10). Figure 6 illustrates the variation of x versus W2 in comparison with the prediction from our model in the case of carbon fibre-SBR systems. Any other theoretical approach is able to explain these high values of x. 

In recent years, lamellar nanofiUers have been established as the most important filler type for barrier and mechanical reinforcement. Dal Point et al. reported a novel nanocomposite series based on styrene-butadiene rubber (SBR latex) and alpha-zirconium phosphate (a-ZrP) lamellar nanofiUers. The use of surface modified nanofiUers improvement the mechanical properties. However, no modification of the gas barrier properties is observed. The addition of bis(triethoxysilylpropyl) tetrasulfide (TESPT) as coupUng agent in the system is discussed on the nanofiUer dispersion state and on the fiUer-matrix inteifacial bonding. Simultaneous use of modified nanofillers and TESPT coupling agent is found out with extraordinary reinforcing effects on both mechanical and gas barrier properties [123]. 

At the same time, Peddini et al. described the preparation of nanocomposites from styrene-butadiene mbber (SBR) and multiwall carbon nanotubes (MWCNT). MWCNT are important nanostructures due to the exceptionally high modulus and aspect ratios there has been much interest in using them as reinforcing agents for polymer composites. Styrene-butadiene rubber (SBR), commonly used as a tread stock for tires, is employed here as the matrix for creation of a masterbatch with oxidized MWCNT (12.3-15 wt%). These materials do not show a high level of electrical conductivity as might be expected from a percolation concept, signifying excellent tube dispersion and formation of a bound rubber layer on the discrete MWCNT [126]. 

Transparency. Standard ABS grades are opaque because of the refractive index mismatch between the dispersed rubber phase and the continuous SAN matrix. However, ABS-type systems are available as transparent grades for clear applications, with transparency achieved by the matching of the refractive index of the rubber and matrix phases through the incorporation of comonomers. Typically, refractive index of the rubber phase is increased through the use of styrene-butadiene rubber and the matrix phase reduced and matched to the rubber phase through terpolymerization with methylmethacrylate. 

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