Polystyrenesulfonic acid

Rexyn 101 (polystyrenesulfonic acid), 80-91% yield." This method does not cleave the r-butyldimethylsilyl ether. 

As described above, Steinhardt and Fugitt81 found that the catalytic activity of polystyrenesulfonic acid 37 (HPSt) was higher than that of mineral acid for the add hydrolyses of proteins. Lawrence and Moore82 investigated the hydrolysis rates of glycylpeptides more quantitatively by using cationic... 

Cationic exchanger (crosslinked polystyrenesulfonic acid) was found to be very slightly more effective in the hydrolyses of cane suger than sulfuric acid144. ... 

Chuy, C., Basura, V. L, Simon, E., Holdcroft, S., Horsfall, J. A. and Lovell, K. V. 2000. Electrochemical characterization of ethylenetetrafluoroethylene-g-polystyrenesulfonic acid solid polymer electrolytes. Journal of the Electrochemical Society 147 4453 58. 

A glass substrate carrying an ITO film having a thickness of 150 nm was spin coated with 70 nm of poly(3,4)ethylenedioxythiophene/polystyrenesulfonic acid thin film and then dried at 200°C for 10 minutes. A 50-nm coating of a selected experimental agent was sprayed onto the initial film and dried. Lithium fluoride, calcium, and aluminum were then vapor-deposited at 0.4 nm, of 5 and 180nm, respectively. 

Dioxanes are prepared from 1,3-diols and either an aldehyde,555 356 a ketone,557 an acetal,192 or mcthoxyniethyl chloride.558 4-Toluenesulfonic acid is the catalyst of choice,19255 5556 e.g. diol 9 reacts with isobutyraldchyde to give the cyclic acetal 10.556 For the intramolecular transacetalization of bis(methoxymethyl)-protected diol 11 to dioxane 12, Amberlyst-15 (beaded polystyrenesulfonic acid) is needed.556... 

B. Gupta, M. Staub, G.G. Scherer, and D. Grman. Surface nonhomogeneity in radiation grafted FEP-g-polystyrenesulfonic acid proton-exchange membranes. Journal of Polymer Science Part A Polymer Chemistry 33, 1545-1549 1995. 

An acidic resin can be used in place of sulfuric acid for the von Pechmann" " coumarin synthesis. For condensalions such as Ihal of resorcinol with ethyl ticeto-acetate, the two resins indicated appear to he equally salisl actory (/eu-Karb is a British polystyrenesulfonic acid). Use of a resin slmplllled puriflcalion of the eroduot. 

PSSA = polystyrenesulfonic acid Py = pyridine, usually as a solvent... 

H.P. Gregor, H. Jacobson, R.C. Shair and D.M. Wetstone, Interpolymer ion-exchange membranes. I. Preparation and characterization of polystyrenesulfonic acid-dynel membranes. J. Phys. Chem., 1957, 61, 141-147. 

The dielectric properties of polystyrenesulfonic acid membranes in their H form have also been studied over the frequency range of 10 -10 Hz, with H O content and temperature as parameters. It was concluded that the presence of water in the membrane gives rise to a specific, water induced relaxation process which is characterized by high dielectric constant, loss, and dielectric increment, Ae . 

We have successfully identified an alternative polymer electrolyte membrane, a polystyrenesulfonic acid-based system, for direct methanol fuel... 

Fig. 11. Hybrid multilayers made of (a) polycationic dendrimers and polystyrenesulfonic acid (b) polycationic dendrimers and glucose oxidase (c) thickness of the multilayers obtained in (a) depending on the number of layers and measured by ellipsometry...

Naflon-H , polystyrenesulfonic acid) FcClj, BFj, AICI3, CFjCOOH... 

Kameo et ai. reported [50] the use of polystyrenesulfonic acid as a catalyst in the nitration of aromatics with HNO3. Nitration of toluene with 90% HNO3 over dried sulfonated polystyrene resin (Rohm and Haas amberlite IR-120) was also reported by Wright et al. at 65-70°C to give an ortho para isomer ratio of only 0.68, much lower than usual ortho-para ratios in acid-catalyzed nitrations [11]. It is considered that the nitroniura ion is strongly ion paired to the resinsulfonic acid. The ion-pair salt thus formed is much bulkier than the free nitronium ion or such nitronium salts as NO2 BF4. 

In view of these considerations and the limitations of polystyrenesulfonic acids, we studied superacidic Nafion-H perfluorosulfonic-acid-resin-caialyzed nitration of aromatics with nitric acid under conditions of azeotropic removal of water (azeotropic nitration) [12]. The azeotropic removal of water in Nafion- H -catalyzed nitration allows utilization of nitric acid to a significantly greater extent than do conventional conditions of nitration. Both fuming and concentrated nitric acid are effective (Table VII). 

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