Diene rubbers styrene-butadiene rubber

Compared to the vast literature on most of the thermoplastic or thermosetting polymer-clay nanocomposites, reports of rubber-clay nanocomposites are much more limited. Much more research is needed to understand the complex nature of these nanocomposites and to identify the factors that have the most significant influence on their physical, mechanical, thermal, barrier, and dynamic mechanical properties. The several examples of rubber-clay nanocomposite that have been covered in this chapter indicate that to date rubber nanocomposite research has largely concentrated on the natural rubber, ethylene propylene diene rubber, styrene-butadiene rubber, and nitrile rubbers. The main factors found to influence final properties were type of clay and its treatment, clay... 

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]. 

The general reaction chemistry used in the synthesis of common rubbers and elastomers mentioned in Table 21.1 is described in the following. The discussion covers four types of rubbers styrene-butadiene rubbers (SBRs), polybutadiene, ethylene-propylene-diene rubbers, and thermoplastic polyurethanes. 

Sircar and co-workers [8] compared experimental and data from the literature for the Tg of some common elastomers determined by different thermal analysis techniques, including DSC, TMTA, DMTA, dielectric analysis and thermally stimulated current methods. Elastomers examined include natural rubber, styrene-butadiene rubber, polyisoprene, polybutadiene, polychloroprene, nitrile rubber, ethylene-propylene diene terpolymer and butyl rubber. Tg values obtained by DSC, TMA and DMTA were compared. Experimental variables and sample details, which should be included along with Tg data were described, and the use of Tg as an indication of low temperature properties was discussed. 

Rubbers with very poor resistance Diene mbbers (e.g., natural rubber, styrene butadiene rubber, nitrile mbber, budadiene mbber)... 

Krishen [119] has described a procedure for the determination of these monomer units. He quantitatively analysed the gaseous pyrolysis products from natural rubber, styrene-butadiene rubber and ethylene-propylene diene terpolymer rubber by gas chromatography. He showed that the 2-methyl-2-butene peak was linear with the natural rubber content of the sample. Styrene-butadiene rubber was determined from the peak area of the 1,3-butadiene peak. The ethylene-propylene-terpolymer content was deducted from the 1-pentane peak area of the pyrolysis products. Some of the pyrolysis products identified are shown in Table 4.10. 

NATURAL RUBBER, STYRENE-BUTADIENE RUBBER AND ETHYLENE-PROPYLENE-DIENE TERPOL YMER IN CURED STOCKS... 

The elastomer produced in greatest amount is styrene-butadiene rubber (SBR) Annually just under 10 lb of SBR IS produced in the United States and al most all of it IS used in automobile tires As its name suggests SBR is prepared from styrene and 1 3 buta diene It is an example of a copolymer a polymer as sembled from two or more different monomers Free radical polymerization of a mixture of styrene and 1 3 butadiene gives SBR... 

Other polymers used in the PSA industry include synthetic polyisoprenes and polybutadienes, styrene-butadiene rubbers, butadiene-acrylonitrile rubbers, polychloroprenes, and some polyisobutylenes. With the exception of pure polyisobutylenes, these polymer backbones retain some unsaturation, which makes them susceptible to oxidation and UV degradation. The rubbers require compounding with tackifiers and, if desired, plasticizers or oils to make them tacky. To improve performance and to make them more processible, diene-based polymers are typically compounded with additional stabilizers, chemical crosslinkers, and solvents for coating. Emulsion polymerized styrene butadiene rubbers (SBRs) are a common basis for PSA formulation [121]. The tackified SBR PSAs show improved cohesive strength as the Mooney viscosity and percent bound styrene in the rubber increases. The peel performance typically is best with 24—40% bound styrene in the rubber. To increase adhesion to polar surfaces, carboxylated SBRs have been used for PSA formulation. Blends of SBR and natural rubber are commonly used to improve long-term stability of the adhesives. 

Use of organosilanes in reinforced rubbers 5 (NR natural rubber, SBR styrene-butadiene rubber, EPDM ethylene-propylene-diene rubber)... 

Rubbers were compounded with the ingredients and vulcanized as shown in Table I. The vulcanizates were cut off from the sheet with JIS (Japanese Industrial Standard) No. 3 dumbbell cutter to prepare the samples for heat aging. Styrene-butadiene rubber (SBR), cw-polybuta-diene (BR), and butyl rubber (HR) vulcanizates were aged in the Geer oven at 100°C. for 48 hours. Natural rubber (NR) was aged at 100°C. for 36 hours. 

The elastomer determines most of the physical and chemical characteristics of a rubber compound. Typical elastomers are natural elastomers such as natural rubber (NR), sometimes called crepe, and synthetic elastomers such as butyl (including chlorobutyl and bromobutyl), ethylene propylene diene monomer (EPDM), and styrene butadiene rubber (SBR). A list of commonly used elastomers is shown in Table 2. 

Copolymerization of styrene and conjugated dienes is another attractive subject which provides the most commonly used styrene-butadiene rubbers (SBRs). Boisson reported that by using neodymium amide Nd N(SrMe3)2 3 and TIBA and DEAC, SBRs with 10-15 mol% of styrene were produced [189], although drops in both activity and molecular weight were observed as compared with those of... 

Amounts are parts by weight per 100 parts by weight rubber. Diene rubber includes natural rubber, polyisoprene rubber, butadiene rubber, and styrene-butadiene rubber. 

Elastomers include natural rubber (polyisoprene), synthetic polyisoprene, styrene-butadiene rubbers, butyl rubber (isobutylene-isoprene), polybutadiene, ethylene-propylene-diene (EPDM), neoprene (polychloroprene), acrylonitrile-butadiene rubbers, polysulfide rubbers, polyurethane rubbers, crosslinked polyethylene rubber and polynorbomene rubbers. Typically in elastomer mixing the elastomer is mixed with other additives such as carbon black, fillers, oils/plasticizers and accelerators/antioxidants. 

Polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), polystyrene (PS), polymethylmethacrylate (PMMA) Ethylene-tetratluoro-ethylene (ETFE), tetrafluoroethylene/ hexafluoropropylene (THV), polyethylene (PE), polypropylene (PP) Epoxy resin (EP), polyester resin (UP), phenol resin (PF), resorcin resin (RF), polyurethane (PUR) Styrene-butadiene-rubber (SBR), polybutadiene-rubber (BR), ethylene-propylene-diene-rubber (EPDM)... 

Polysiloxane Styrene-butadiene rubber Ethylene-propylene-diene terpolymer... 

Elastomers are elastic materials that stretch to high extensions and rapidly recover their original dimensions once the applied stress is released. They are formed by a loose network. Styrene-butadiene rubber (SBR) and ethylene-propylene-diene monomer (EPDM) are examples of important elastomers. 

Accelerated-sulfur vulcanization is the most widely used method. For many applications, it is the only rapid crossUnking technique that can, in a practical manner, give the delayed action required for processing, shaping, and forming before the formation of the intractable vulcanized network. It is used to vulcanize natural rubber (NR), synthetic isoprene rubber (IR), styrene-butadiene rubber (SBR), nitrile rubber (NBR), butyl rubber (HR), chlorobutyl rubber (ClIR), bromobutyl rubber (BUR), and ethylene-propylene-diene-monomer rubber (EPDM). The reactive moiety for all of these elastomers can be represented by... 

Properties Ethylene propylene diene Nitrile rubber Poly- chloroprene Natural rubber Poly- isoprene Styrene butadiene rubber Butyl rubber Polybutadiene... 

Use of nanoparticles as fillers in mbbers is highly relevant because end use applications of rubber compounds require filler reinforcement. Most of the literature on rubber nanocomposites is based on the use of nanoclay as the filler. It has been shown that incorporation of nanoclay in synthetic rubbers, like styrene butadiene rubber (SBR), chloroprene rubber (CR), nitrile rubber (NBR), ethylene propylene diene monomer (EPDM) mbber etc. enhances the mechanical, anti-ageing and barrier properties. 

A.S.Z. Naseri, A. JalaU-Arani, A comparison between the effects of gamma radiation and sulfur cure system on the microstructiire and crosslink network of (styrene butadiene rubber/ethylene propylene diene monomer) blends in presence of nanoclay. Radiation Physics and Chemistry, ISSN 0969-806X 115 (October 2015) 68-74. http //dx.doi. org/10.1016/jjadphyschem.2015.05.037. 

NR = natural rubber SBR = styrene-butadiene rubber EPDM = ethylene-propylene-diene monomer CSM = chlorosulfonated polyethylene and PE = polyethylene. 

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