Styrene-1,3-butadiene

Pyrolysis coupled with gas chromatography - mass spectroscopy (Py-GC-MS) in an inert atmosphere has been used to study thermal degradation products of styrene-butadiene rubber (SBR). Introduction of samples, using the pyrolysis carrier 

Several additional products formed by the Diels-Alder condensations of butadiene and styrene were also characterised by mass spectrometry (MS) and by matching the pyrogram retention times of the samples with retention times obtained for samples spiked with the same dimers. Vapour phase dimerisation of butadiene is known to be a clear-cut bimolecular reaction. Formation of the dimers can take place in the pyrocell as well as in the gas chromatograph (GC) transfer line. Equation 2.4 shows the dimerisation of two molecules of butadiene to form a molecule of 4-vinyl-l-cyclohexene  

By the same mechanism a molecule of styrene reacts with a molecule of butadiene to give a molecule of 4-phenylcyclohexene as shown in Equation 2.5. 

Pyrograms obtained for the styrene-butadiene copolymer also show the presence of trace levels of styrene dimer m/e = 208) and trimer (m/e = 312). The major mechanism for producing styrene dimers and trimers by pyrolysis is attributed to thermal degradation which occurs in the pyrolysis of polystyrene (PS). A relatively small amount of trimers are formed as a result of styrene recombination  

Ozonisation followed by gel permeation chromatography (GPC) has been used by Tanaka and co-workers [78,79] to study sequencing of vulcanised styrene copolymers. Tanaka and co-workers [78, 79] carried out the ozonolysis in methylene dichloride and examined the fractions obtained following GPC by H-NMR. These workers found nonad, diad and triad styrene sequences flanked by 1,4-butadiene units and long styrene sequences  

Pattuelli [81] also used ozonolysis - HPLC in sequencing studies on styrene-butadiene copolymers. 

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SBP spirits Special boiling point spirits. SBR Styrene butadiene rubber. 

Styrene is manufactured by alkylating benzene with ethene followed by dehydrogenation, or from petroleum reformate coproduction with propylene oxide. Styrene is used almost exclusively for the manufacture of polymers, of which the most important are polystyrene, ABS plastics and styrene-butadiene rubber. U.S. production 1980 3 megatonnes. 

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... 

Poly butylene (PB) Styrene-butadiene block copolymer... 

Styrene-butadiene copolymer Poly(vinyl formal)... 

Styrene-Butadiene-Styrene Block Copolymers. Styrene blocks associate into domains that form hard regions. The midblock, which is normally butadiene, ethylene-butene, or isoprene blocks, forms the soft domains. Polystyrene domains serve as cross-links. 

Styrene-acrylonitrile copolymer Styrene- butadiene copolymer, high-impact Polysulfone ... 

Styrene-butadiene rubber is prepared from the free-radical copolymerization of one part by weight of styrene and three parts by weight of 1,3-butadiene. The butadiene is incorporated by both 1,4-addition (80%) and 1,2-addition (20%). The configuration around the double bond of the 1,4-adduct is about 80% trans. The product is a random copolymer with these general features ... 

Styrene-butadiene rubber (SBR) is also known as government rubber styrene (GRS) and Buna S. 

Styrene-butadiene rubber (SBR) (also known as Buna S) 0.94 40-100 400-600 1600-3700 -60 107... 

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. 

Butadiene-styrene, butadiene-acrylomtrile, acrylate emulsion... 

COLORANTS FORFOOD,DRUGS,COSTffiTICS AND TffiDICALDEVICES] (Vol 6) ESBR See Emulsion styrene-butadiene rubber. 

SAN copolymers [ACRYLONITRILE POLYTffiRS - SURVEY AND SAN (STYRENE-ACRYLONITRILECO-POLYTffiRS)] (Vol 1) -SBRfrom [STYRENE-BUTADIENE RUBBER] (Vol 22)... 

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