P- styrene

Molecular weight calibration from a monomer to several million daltons can be carried out by a variety of techniques. Because narrow standards of p(methyl methacrylate) (pMMA) are available, these are often used. Narrow standards of p(styrene) (pSty) are also available and can be used. Using the Mark-Houwink-Sakurada equation and the parameters for pSty and pMMA, a system calibrated with pSty can give pMMA-equivalent values, and vice versa. 

P-p-C H4Ph2CCl, Pyr, 25°, 5 days, 90%, where P = styrene-divinyl-benzene polymer. Triarylmethyl ethers of primary hydroxyl groups in glucopyranosides have been prepared using a polymeric form of triphenylmethyl chloride. Although the yields are not Improved, the workup is simplified. 

Aryldiazomethane can also be used for iron porphyrin-catalyzed alkene cyclopropanation [55]. For example, the treatment of p-tolyldiazomethane with styrene in the presence of [Fe(TTP)] afforded the corresponding arylcyclopropapane in 79% yield with a high transicis ratio of 14 1 (eq. 1 in Scheme 11). Interestingly, when bulkier mesityldiazomethane was used as carbene source, ds-selectivity was observed (cisitrans = 2.0 1). Additionally, mesityldiazomethane was found to react with frans-p-styrene, the latter was found not to react with EDA or trimethyl-silyldiazomethane under the similar reaction conditions, to give l-mesityl-2-methyl-3-phenylcyclopropane in 35% yield. Trimethylsilyldiazomethane is also an active carbene source for [Fe(TTP)]-catalyzed cyclopropanation of styrene, affording l-phenyl-2-trimethylsilylcyclopropane in 89% yield with transicis ratio of 10 1 (eq. 2 in Scheme 11). 

ESCA analysis showed a similar trend of incomplete surface coverage for the IK systems. Also, no domains were visible in any of the IK styrenic graft systems by TEM. There is an expected trend with respect to solubility parameter, p(t-butyl styrene) (6 s 8.1) has a solubility parameter much closer to that of polydimethylsiloxane (S a 7.3) than does p(p-methyl styrene) which is closer than p(styrene) (S s 9.1). 

The formation of complexes involved two steps. In the first step, the ionene bromide was converted to ionene hydroxide by replacing the Br ions with OH ions. In the second step, the equivalent quantities of acid and ionene were mixed together. Polymerizations were carried out mostly in water-isopropanol solution. AIBN or 4,4-azobis-4-cyanovaleric acid was used as initiator. Polymerization of p-styrene sulfonic acid onto various ionenes was studied as a function of the charge density of the template. It was shown that a linear dependence of rate on charge density prevailed. From the results obtained, the authors concluded that the monomeric counterions possess mobility along the linear template. PolyCvinyl sulfonate) prepared on the template displays a different stereo-structure from polyCvinyl sulfonate) prepared in solution. 

The method proposed by Blumstein at is based on the conductivity measurements. It is suitable for the systems in which shift of ionization equilibrium during polymerization takes place. This method was successfully applied to follow template polymerization of p-styrene sulfonic acid in the presence of polycationic ionenes used as template. The results confirm data obtained for the same system by another methods. 

Many ionogenic monomers containing a polymerizable carbon double bond have been reported in the literature, and therefore a wide variety of anionic, cationic, and amphophilic polyelectrolytes may be synthesized using free radical polymerizations. Examples of anionic ionogenic monomers which have been used to synthesize anionic polyelectrolytes include acrylic acid [4-10], methac-rylic acid [6-8,11,12], sodium styrenesulfonate [7,13,14], p-styrene carboxylic... 

W. F. Graydon and R. J. Stewart (41) also compared the membrane potentials with the values according to equation (46). The membrane investigated was a copolymer of p-styrene sulfonic acid and styrene crosslinked with divinyl benzene. In the large majority of cases the experimental values were lower than those according to equation (46). The smaller part of this difference could be attributed to the transport of the co-ions and was calculated roughly. The greater part was attributed to water transport. From this the transport number of water was calculated it varied from 1 to about 60. It was found that the water transport was proportional to the water content and inversely proportional to the number of crosslinks. A provisional direct measurement was effected of a water transport number. The value corresponded rather well with the indirect determination as described above. 

The DSC results support a segregated two-stage latex particle which is rich in p-styrene and in p-n-butyl acrylate. 

The interaction between tris(2,2 -dipyridyl)ruthenium(II) with poly(p-styrene sulfonate) [80] due to the outer-sphere cooperative processes yields the following structures ... 

DCC is also used in nucleotide chemistry to esterify a sugar hydroxyl group with a phosphate group in another nucleotide or oligonucleotide unit. Also p-styrene based polymers with a pyridyl-2-ethanol end group are reacted in pyridine with 3 -0-acetyl-desoxythimidine-5 -phosphate in the presence of DCC." The reaction of mono esters of phosphoric acid with alcohols or phenols, in the presence of DCC, affords phosphoric acid diesters in high yield." This reaction is widely used in nucleic acid chemistry. 

Johnson et al. were the first to prepare enantiomerically pure aminosulfoxonium ylide 3.73 from 3.72, which on reaction with benzaldehyde gave (P)-styrene oxide (3.69) in 20% ee. The reaction of aminosulfoxonium ylide 3.74 with heptaldehyde gave the corresponding epoxide 3.75 with opposite enantioselectivity (39% ee, S) as expected. 

It is increasingly apparent that polar characteristics of radicals are important in organic synthesis [122] and the effect of fluorine on the polarity of radicals is very significant. Reactions of perfluoroalkyl radicals with a series of substituted p-styrenes [123] (Figure 4.51) shows that the rate constant for radical addition to alkenes increases as the alkene becomes more electron-rich (Table 4.16) and, in similar additions, perfluoroalkyl radicals reacted 40000 times faster with 1-hexene than the corresponding alkyl radicals. 

Figure 2. IR shifts of the —C=N stretching band as function of composition P, styrene mol fraction in the copolymer. Key O, data of Grasselli (1973)and 9, this...

Cb 2Cr Cb + 2e NH2OH, phenol, aniline, mustard gas, mercaptans, 8-hydroxyquinoline, olefins As(III), P, styrene, fatty acids... 

Synthesised catalysts were named as NPML where N=percent crosslinking, P = styrene-divinyl benzene copolymer, M = Metal (Ru) and L=Ligand (DAP). The following catalysts were prepared. 

Sodium-p-styrene sulfonate (SST) was supplied by Exxon Research and Engineering Co. and used without further purification. n-Butyl acrylate was a product of Polysciences, Inc. and was passed through a column of neutral alumina, twice, before use to remove the inhibitor. Potassium persulfate and sodium bisulfate were recrystallized from distilled water and dried under vacuum. 

Liquid crystalline azobenzene polymers can undergo photoisomerization on irradiation at 360 or 450 nm on gold films. This permits changing the refractive index of the film depending upon the wavelength used136. A study has examined the photopolymerization of p-styrene sulphonate counteranions associated with monolayers of disulphide amphiphiles as self-assembled monolayers on gold137. 

Monomers 4VP, 4-vinylpyridine NIPAAm, jV-isopropylacrylamidc AA, acrylic acid PEGMA, poly (ethylene glycol) methacrylate SPE, MAI-dimethyl-AW2-methacryloyloxycthyl-/V-0-sulfopropyl)amm<>-nium betaine AMPS, 2-acrylamido-2-methyl-l-propanesulfonic acid qDMAEMA, quaternary 2-dimethylaminoethyl methacrylate St, styrene HEMA, 2-hydroxyethyl methacrylate HEA, 2-hydro-xyethyl acrylate DMAEMA, 2-dimethylaminoethyl methacrylate MAA, methacrylicacid NaSS sodium p-styrene sulfonate AC, [(2-acryloyloxy)ethyl]trimethyl ammonium chloride GMA, glycidyl methacrylate NVP, jV-vinylpyrrolidone MAn, maleic anhydride BVE n-butyl vinyl ether AAm, acrylamide DEAAm, MA-diethylacrylamidc DMAAm, MA -dimethylacrylamidc MMA, methyl methacrylate. 

To overcome such limitations, Imura et al. covered the surface of a silica gel with sulfonated cross-linked polystyrene [5]. After adsorption of styrene, divinyl-benzene, and r-butyl peroxide and subsequent free-radical polymerization, the acid groups are introduced via classical sulfonation. Control of the thickness of the crosslinked polymer layer on the surface is essential to prevent pore clogging. This sulfonated polystyrene-Si02 hybrid material preserves a large specific surface area, with a typical ion-exchange capacity of 1.8 meq g. Alternatively, a sulfonated layer can be deposited on silica by copolymerization of silica-supported methacrylate and potassium p-styrene sulfonate [6]. 

Beilstein Handbook Reference) ar-Methylstyrene Benzene, ethenylmethyl- BRN 1209317 CCRIS 2369 EINECS 246-562-2 Ethenylmethylbenzene HSDB 1035 Methylethenylbenzene Methylstyrene Methylvinylbenzene NCI-C56406 NSC 4832 Styrene, ar-methyl- Styrene, methyl- Styrene, methyl- (mixed isomers) a,p-Styrene Toluene, vinyl- (mixed isomers) Tolylethylene UN2618 Vinyl toluene 3- and i-Vinyl toluene (mixed isomers) Vinyl toluene Vinyitoluene Vinylloluene, industrial Vinyltoluenes, inhibited. 

Also worthy of mention is the introduction of conductive electron-beam resists that eliminate the charging effect that is so troublesome in electron-beam lithography. Todokaro et al. accomplished this by using a partially chloromethylated poly(diphenylsiloxane) as the top imaging resist in a bilayer system, and using the ionically conductive ammonium salt of poly(p-styrene sulfonate) (XXI) as the bottom layer. 

Copolymerisation of the monomeric divinyl substituted Mn complex with styrene and DVB. Enantioselective epoxidation of styrene and cts-P-styrene using various oxidants, Cis / trans ratio of epoxides range from 73 27 to 93 7 enantiomeric excesses from 4 to 41%. 

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