Styrene-butadiene-rubber, application

These admixtures are used to increase the bond strength in repair applications, to decrease shrinkage, increase tensile strength, etc. The polymers used include latexes, redispersible polymer powders, water-soluble polymers, liquid resins, and monomers. In practieal applications, styrene butadiene rubber, polyacrylic ester and polyvinylidene chloride-vinyl chloride, methylcellulose, etc., have been used. 

Polymers of chloroprene (structure [XII]) are called neoprene and copolymers of butadiene and styrene are called SBR, an acronym for styrene-butadiene rubber. Both are used for many of the same applications as natural rubber. Chloroprene displays the same assortment of possible isomers as isoprene the extra combinations afforded by copolymer composition and structure in SBR offsets the fact that structures [XIIll and [XIV] are identical for butadiene. 

Butyl phenolic resin is a typical tackifier for solvent-borne polychloroprene adhesives. For these adhesives, rosin esters and coumarone-indene resins can also be used. For nitrile rubber adhesives, hydrogenated rosins and coumarone-indene resins can be used. For particular applications of both polychloroprene and nitrile rubber adhesives, chlorinated rubber can be added. Styrene-butadiene rubber adhesives use rosins, coumarone-indene, pinene-based resins and other aromatic resins. 

Fig. 25. Evolution of the tack of polychloroprene-aromatic hydrocarbon resin blends as a function of the resin content. Tack was obtained as the immediate T-peel strength of joints produced with 0.6 mm thick styrene-butadiene rubber strips placed in contact without application of pressure. Peeling rate = 10 cm/min.

Polymers can be modified by the introduction of ionic groups [I]. The ionic polymers, also called ionomers, offer great potential in a variety of applications. Ionic rubbers are mostly prepared by metal ion neutralization of acid functionalized rubbers, such as carboxylated styrene-butadiene rubber, carboxylated polybutadiene rubber, and carboxylated nitrile rubber 12-5]. Ionic rubbers under ambient conditions show moderate to high tensile and tear strength and high elongation. The ionic crosslinks are thermolabile and, thus, the materials can be processed just as thermoplastics are processed [6]. 

FIGURE 27.4 ATR-IR spectra of 2 wt% trichloroisocyanuric acid (TCI) solution in MEK-treated styrene-butadiene rubber (SBR). Application of the chlorinating agent by immersion or by brush. (From Romero-Sanchez, M.D., Pastor-Bias, M.M., and Martfn-Martfnez, J.M., J. Adhes. Sci. TechnoL, 15, 1601, 2001.)... 

S. Bandyopadhyay, S.L. Agrawal, P. Sajith, N. Mandal, S. Dasgupta, R. Mukhopadhyay, A.S. Deuri, and S.C. Ameta, Research on the application of recycled waste RFL (Resorcinol-Formaldehyde-Latex) dip solid in Styrene Butadiene Rubber based compounds. Progress in Rubber, Plastics and Recycling Technology, 23(1), 21, 2007. 

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. 

Patil and Pandit [36] investigated the application of hydrodynamic cavitation and acoustic cavitation for synthesis of nano-scale particles of styrene butadiene rubber. The setup used for the generation of hydrodynamic cavitation was essentially... 

As one of the most versatile copolymers in the world today, styrene-butadiene rubber is used in a number of different applications around the world. Some facts about the development of styrene-butadiene rubber and some of the products that are created with this strong and reliable synthetic rubber are described below. 

Order-disorder transitions and spinodals were computed for linear multi block copolymers with differing sequence distributions by Fredrickson et al. (1992). This type of copolymer includes polyurethanes, styrene-butadiene rubber, high impact polystyrene (HIPS) and acrylonitrile-butadiene-styrene (ABS) block copolymers. Thus the theory is applicable to a broad range of industrial thermoplastic elastomers and polyurethanes. The parameter... 

Other reported TG-MS applications concern polybutadiene [153], styrene-butadiene rubbers [153], gums [14], polyisoprenes [52], polyurethanes [144, 146, 147, 166], ABS [144], chlorosulphonated polyethylene elastomer [169, 170] and elastomer blends (NBR/SBR/ BR) [13]. Table 1.5 summarises the use of advanced TG-MS systems in elastomer analysis. 

As a result of its saturated polymer backbone, EPDM is more resistant to oxygen, ozone, UV and heat than the low-cost commodity polydiene rubbers, such as natural rubber (NR), polybutadiene rubber (BR) and styrene-butadiene rubber (SBR). Therefore, the main use of EPD(M) is in outdoor applications, such as automotive sealing systems, window seals and roof sheeting, and in under-the-hood applications, such as coolant hoses. The main drawback of EPDM is its poor resistance to swelling in apolar fluids such as oil, making it inferior to high-performance elastomers, such as fluoro, acrylate and silicone elastomers in that respect. Over the last decade thermoplastic vulcanisates, produced via dynamic vulcanisation of blends of polypropylene (PP) and EPDM, have been commercialised, combining thermoplastic processability with rubber elasticity [8, 9]. 

Since compounds of the type XVII have shown comparable activity in a number of systems including cis-polybutadiene, styrene-butadiene rubber, and ethylene-propylene rubber, they have some commercial promise, and development work on these compounds is continuing. Nevertheless, they are not completely nondiscoloring, and in certain applications, particularly carboxylated styrene-butadiene latex films, yellow discoloration caused by the antioxidant is a serious drawback. We therefore turned our attention to ortho-linked compounds derived from 2,4-dialkylphenols. 

The major general purpose rubbers are natural rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, and ethylene-propylene rubber. These rubbers are used in tires, mechanical goods, and similar applications. Specialty elastomers provide unique properties such as oil resistance or extreme heat stability. Although this differentiation is rather arbitrary, it tends also to classify the polymers according to volumes used. Styrene-butadiene rubber, butadiene rubber, and ethylene-propylene rubber account for 78 percent of all synthetic rubber consumed. 

The largest-volume synthetic rubber consumed is styrene-butadiene rubber (SBR). In 2003, SBR solid rubber accounted for 41 percent of all synthetic rubber. If SBR latex and carboxylated SBR latex are included, its share increases to 55 percent. The major application of solid SBR is in the automotive and tire industry, accounting for approximately 70 percent of the use. Therefore, SBR has been tightly tied to the tire business.25... 

Emulsion polymerization is the basis of many industrial processes, and the production volume of latex technologies is continually expanding—a consequence of the many environmental, economic, health, and safety benefits the process has over solvent-based processes. A wide range of products are synthesized by emulsion polymerization, including commodity polymers, such as polystyrene, poly(acrylates), poly (methyl methacrylate), neoprene or poly(chloroprene), poly(tetrafluoroethylene), and styrene-butadiene rubber (SBR). The applications include manufacture of coatings, paints, adhesives, synthetic leather, paper coatings, wet suits, natural rubber substitutes, supports for latex-based antibody diagnostic kits, etc. ... 

Technology for preparing nanocomposites directly via compounding has been investigated by Vaia, Ishii, and Giannelis. Industrial R D efforts have focused on process technology (e.g., melt or monomer exfoliation processes), as there are a number of polymers (e.g., polyolefins) that do not lend themselves to a monomer process. Nanocomposites with a variety of polymers, including polyacrylates or methacrylates, polystyrene, styrene-butadiene rubber, epoxy, polyester, and polyurethane, are amenable to the monomer process. The enhancement of mechanical properties, gas permeability resistance, and heat endurance are the primary objectives for the application of PCN, and their success will establish PCNs as a major commercial product. 

Styrene-butadiene rubber could be produced by using emulsion and solution process, thus it can be divided into emulsion-polymerized styrene-butadiene rubber (E-SBR) and solution-polymerized styrene-butadiene rubber (S-SBR). In this entry, we will describe their development and introduce their synthesis process, relationship between structure and property, processing property, blends, and applications. 

Despite the introduction of synthetic elastomers, ceramics and other abrasion resisting metals such as manganese, natural rubber holds a dominant position in this field of application and is the primary choice for abrasion resistance. Synthetic rubbers (particularly styrene-butadiene rubber which is dominant in the tyre industry sector) are used in dry abrasion application such as general purpose abrasion resistant sheets and conveyor belt covers, since the rubber can be reinforced with fine particles of carbon blacks to achieve dry abrasion resistance close to that of natural rubber. It should be noted that styrene-butadiene rubber is inferior to natural rubber in cutting and chipping resistance. 

Improvement of Mechanical Properties. The most important application of SAS, and one of the oldest, is the control of the mechanical properties of rubber. SAS are important additives for both styrene-butadiene rubber (SBR) and natural rubber (NR), second in importance only to carbon black (51, 52). Figure 5 demonstrates the increase in tensile strength at room temperature for silicone rubber with various reinforcing fillers and kieselguhr. An improvement is also brought about in the mechanical strength of fluoroelastomers and other special kinds of rubber (51). Table VI summarizes the improvements that may be achieved in other fields. 

SMA copolymers and terpolymers have also been used for blending with PVC to improve the heat distortion temperature and processability of PVC. These blends also contain a rubbery component for impact modification that is usually a high rubber ABS or a polymethyl methacrylate grafted styrene-butadiene rubber (MBS). For improved weatherability, acrylic rubber modified PVC has been used for blending with SMA copolymers and terpolymers (Table 15.4). The market for SMA/PVC blends is still relatively low in volume with only a few applications such as in business machine housings as a low cost replacement for flame retarded ABS. 

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