Styrene-butadiene rubbers hydrogenation

CAS name - styrene-butadiene rubber, hydrogenated, block, triblock ... 

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. 

Fumed silicas (Si02). Fumed silicas are common fillers in polychloroprene [40], natural rubber and styrene-butadiene rubber base adhesives. Fumed silicas are widely used as filler in several polymeric systems to which it confers thixotropy, sag resistance, particle suspension, reinforcement, gloss reduction and flow enhancement. Fumed silica is obtained by gas reaction between metallic silicon and dry HCl to rend silica tetrachloride (SiCU). SiC is mixed with hydrogen and air in a burner (1800°C) where fumed silica is formed ... 

Most rubbers used in adhesives are not resistant to oxidation. Because the degree of unsaturation present in the polymer backbone of natural rubber, styrene-butadiene rubber, nitrile rubber and polychloroprene rubber, they can easily react with oxygen. Butyl rubber, however, possesses small degree of unsaturation and is quite resistant to oxidation. The effects of oxidation in rubber base adhesives after some years of service life can be assessed using FTIR spectroscopy. The ratio of the intensities of the absorption bands at 1740 cm" (carbonyl group) and at 2900 cm" (carbon-hydrogen bonds) significantly increases when the elastomer has been oxidized [50]. 

QCMB RAM SBR SEI SEM SERS SFL SHE SLI SNIFTIRS quartz crystal microbalance rechargeable alkaline manganese dioxide-zinc styrene-butadiene rubber solid electrolyte interphase scanning electron microscopy surface enhanced Raman spectroscopy sulfolane-based electrolyte standard hydrogen electrode starter-light-ignition subtractively normalized interfacial Fourier transform infrared... 

Properties of Thermoplastic Elastomeric Composition Based on Hydrogenated Styrene-Butadiene Rubber and Low-Density Polyethelene... 

De Sarkar M., De P.P., and Bhowmick A.K., New polymeric blends from hydrogenated styrene-butadiene rubber and polyethylene. Polymer, 39, 1201, 1998. 

The hydrogenation in a liquid-liquid system with ionic liquids as the catalyst phase was also applied to the hydrogenation of polymers. The first studies were presented by the group of Rosso et al. [91], who investigated the rhodium-catalyzed hydrogenation of polybutadiene (PBD), nitrile-butadiene rubber (NBR) and styrene-butadiene rubber (SBR) in a [BMIM][BF4]/toluene and a [BMIM][BF4]/tolu-ene/water system. The activity of the catalyst followed the trend PBD>NBR> SBR, which is the same order as the solubility of the polymers in the ionic liquid. The values in percentage total hydrogenation after 4 h reaction time were 94% for PBD and 43% for NBR, and after a reaction time of 3 h was 19% for SBR. 

HSBR HTNR HXSBR ICTA Hydrogenated styrene butadiene rubber Hydroxyterminated liquid NR Hydrogenated carboxylated styrene butadiene rubber International Confederation for Thermal Analysis... 

FIG. 18.3 Activation energy of diffusion as a function of Tg for 21 different polymers from low to high temperatures, ( ) odd numbers (O) even numbers 1. Silicone rubber 2. Butadiene rubber 3. Hydropol (hydrogenated polybutadiene = amorphous polyethylene) 4. Styrene/butadiene rubber 5. Natural rubber 6. Butadiene/acrylonitrile rubber (80/20) 7. Butyl rubber 8. Ethylene/propylene rubber 9. Chloro-prene rubber (neoprene) 10. Poly(oxy methylene) 11. Butadiene/acrylonitrile rubber (60/40) 12. Polypropylene 13. Methyl rubber 14. Poly(viny[ acetate) 15. Nylon-11 16. Poly(ethyl methacrylate) 17. Polyethylene terephthalate) 18. Poly(vinyl chloride) 19. Polystyrene 20. Poly (bisphenol A carbonate) 21. Poly(2,6 dimethyl-p.phenylene oxide). 

He, Y. Daniels, E.S. Klein, A. El-Aasser, M.S. Hydrogenation of styrene-butadiene rubber (SBR) latexes. J. Appl. Polym. Sci. 1997, 64, 2047-2056. Abdel-Aziz, M.M. Youssef, H.A. El-Miligy, A.A. Yoshii, F. Makuuchi, K. Effect of polyfunctional monomers on radiation vulcanization of styrene-butadiene rubber. J. Elastomers Plast. 1996, 28, 288-305. 

A proposed expansion of the company s styrene-butadiene rubber production will require an additional 10,000 tons/yr of butadiene as a raw material. For many years, butadiene has been manufactured by dehydrogenating butene or butane over a catalyst at appropriate combinations of temperature and pressure. It is customary to dilute the butene feed with steam (10 to 20 mol HjO/mol butene) to stabilize the temperature during the endothermic reaction and to help shift the equilibrium conversion in the desired direction by reducing the partial pressures of hydrogen and butadiene. The current processes suffer from two major disadvantages ... 

The hydrogenation of polymers such as NBR (acrylonitrile-butadiene rubber), SBR (styrene-butadiene rubber), and PBD (polybutadiene) has been also performed by Ru(ll) compounds associated with phosphine ligands immobilized in classical imidazolium ILs or polyether-modified ammonium salts. ... 

Acrylic elastomer Acrylonitrile-butadiene rubber, hydrogenated Polyethylene, ultrahigh m.w. high-density Polynorbornene Polyurethane elastomer, thermoplastic Styrenated diphenylamine , Styrene-ethylene/butylene-styrene block copolymer seals, chemical-resistant Chlorotrifluoroethylene polymer seals, dynamic aerospace Polyfluoroalkoxyphosphazene seals, dynamic industrial Polyfluoroalkoxyphosphazene seals, dynamic military Polyfluoroalkoxyphosphazene seals, high performance Tetrafluoroethylene/perfluoromethylvinyl ether copolymer seals, oil... 

The rate of chain scission is increased in the presence of active hydrogen (e.g., water), probably due to reaction with carbonyl oxides to form reactive hydroperoxides. Crosslinking products may also be formed, especially with rubbers containing disubstituted double bonds (e.g., polybutadiene, BR, and styrene-butadiene rubber, SBR). 

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. ... 

Several polymeric materials, such as polybutadiene (PDB), nitrile-butadiene rubber (NBR), styrene-butadiene rubber (SBR), and polyst3rrene-6-polybutadiene-6-polystyrene (SBS) were hydrogenated in toluene-IL biphasic systems with [RhCKTPPTSls] (273) and Ru/TPPTS catalysts (274) the latter was prepared in situ from RuCls and TPPTS under hydrogen pressure. In all cases, the hydrogenated polymers were easily recovered in the toluene phase while the IL phase retained the catalysts. 

Natural rubber/chlorosulfonated polyethylene Natural rubber/acrylonitrile butadiene rubber Hydrogenated natural rubber/poly(methyl methacrylate-co-styrene)... 

Meuzelaar et al. [453] have reported experiments with non-vulcanised styrene-butadiene rubber (SBR) in the presence of various catalysts and co-processing runs of coal and lower grade postconsumer polymers (coloured PE and PS, waste rubber tyres, commingled plastic mixture) in a high pressure TG-GC-MS system at a hydrogen pressure of 900 psi. This system is essentially designed for applied rather than analytical TG-GC-MS work. 

A commercial MmNi5-type hydrogen storage alloy was used for the negative electrode material. A slurry containing 96% alloy powders, 4% nickel powder and a proper amount of binders styrene-butadiene rubber and hydroxypropyl methyl cellulose was pasted onto the nickel coated stainless steel strip substrates, and then dried and compressed to obtain the metal hydride electrode. The dimensions of the pasted metal hydride electrode plate were 125 mm X 42 mm X 0.28 mm. 

Representative diene-based polymers include natural rubber (NR), polyisoprene (PIP), PBD, styrene—butadiene rubber (SBR), and acrylonitrile-butadiene rubber (NBR), which together compose a key class of polymers widely used in the rubber industry. These unsaturated polyolefins are ideal polymers for chemical modifications owing to the availability of parent materials with a diverse range of molecular weights and suitable catalytic transformations of the double bonds in the polymer chain. The chemical modifications of diene-based polymers can be catalytic or noncatalytic. The C=C bonds of diene-based polymers can be transformed to saturated C—C and C—H bonds (hydrogenation), carbonyls (hydrofbrmylation and hydrocarboxylation), epoxides (epoxidation), C—Si bonds (hydrosilylation), C—Ar bonds (hydroarylation), C—B bonds (hydroboration), and C—halogen bonds (hydrohalogenation). ... 

Figure 1 Bulk hydrogenation of 1,2-polybutadiene (1,2-PBD), styrene-butadiene rubber (SBR), and acrylonitrile-butadiene rubber (NBR) polymer particles with Wilkinson s catalyst in the presence of excess PPhs.

Diblock copolymers made of hydrogenated PBu and PA6 units (HPBU-PA6) have been s)mthesized in a similar manner (but hydrogenating the hydroxyl-terminated PBu) and used as compatibilizers in low-density poly(ethylene)/PA6 blends (PE/PAfi). " The diblock copolymer exhibited a very relevant interfacial activity, with a reduction of particle size and an improvement of the interfacial adhesion between the incompatible phases. Also hydroxyl-terminated styrene-butadiene rubber (SBR) or poly(E-caprolactone), after reaction with diisocyanates, were anionically copolymerized with CL in order to get block copolymers with improved mechanical properties. ... 

Soaps of Ci2 i8 saturated or monounsaturated fatty acids are used in synthetic rubber polymerization, especially in SBR (styrene butadiene rubber) manufacture. The resulting latex eoagulates easily when acidified, leaving the fatty acid in the polymer, which may remain there as active ingredient of the final compound. Good tackiness of the finished rubber is reached with soaps of hydrogenated or disproportionated - rosin acid as emulsifiers. The world-market for all emulsifiers used as p. is estimated to be 150000—200000 mt/a. 

The hydrogenation of unsaturated polymers and copolymers in the presence of a catalyst offers a potentially useful method for improving and optimizing the mechanical and chemical resistance properties of diene type polymers and copolymers. Several studies have been published describing results of physical and chemical testing of saturated diene polymers such as polybutadiene and nitrile-butadiene rubber (1-5). These reports indicate that one of the ways to overcome the weaknesses of diene polymers, especially nitrile-butadiene rubber vulcanizate, is by the hydrogenation of carbon-carbon double bonds without the transformation of other functional unsaturation such as nitrile or styrene. 

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