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Polystyrene sulfonic acid , -sulfonates

The GBR resin works well for nonionic and certain ionic polymers such as various native and derivatized starches, including sodium carboxymethylcel-lulose, methylcellulose, dextrans, carrageenans, hydroxypropyl methylcellu-lose, cellulose sulfate, and pullulans. GBR columns can be used in virtually any solvent or mixture of solvents from hexane to 1 M NaOH as long as they are miscible. Using sulfonated PDVB gels, mixtures of methanol and 0.1 M Na acetate will run many polar ionic-type polymers such as poly-2-acrylamido-2-methyl-l-propanesulfonic acid, polystyrene sulfonic acids, and poly aniline/ polystyrene sulfonic acid. Sulfonated columns can also be used with water glacial acetic acid mixtures, typically 90/10 (v/v). Polyacrylic acids run well on sulfonated gels in 0.2 M NaAc, pH 7.75. [Pg.400]

Nonfluorinated polymers such as sulfonated polyimides, polystyrene sulfonic acid, sulfonated poly(arylene ether sulfones), polyphosphazene, polybenzimidazole, sulfonatedpolysulfone, sulfonated poly(phthala-zinone ether ketone), and sulfonated poly(ether ether ketone) have been developed as a potential electrolyte membrane for DMFC [4,6,16-23]. [Pg.656]

In the present work it was studied the dependence of analytical characteristics of the composite SG - polyelectrolyte films obtained by sol-gel technique on the content of non-ionic surfactant in initial sol. Triton X-100 and Tween 20 were examined as surfactants polystyrene sulfonate (PSS), polyvinyl-sulfonic acid (PVSA) or polydimethyl-ammonium chloride (PDMDA) were used as polyelectrolytes. The final films were applied as modificators of glass slides and pyrolytic graphite (PG) electrode surfaces. [Pg.306]

Rexyn 101 (polystyrene sulfonic acid), 80-91% yield.This method does not cleave the r-butyldimethylsilyl ether. [Pg.71]

Polymer supported reagents, catalysts, protecting groups, and mediators can be used in place of the corresponding small molecule materials (Sherrington, 1991 Sundell and Nasman, 1993). The reactive species is tightly bound to a macromolecular support which immobilizes it. This generally makes toxic, noxious, or corrosive materials much safer. The use of polystyrene sulfonic acid catalyst for the manufacture of methyl r-butyl... [Pg.37]

The polyamines putrescine, cadaverine, spermidine, and spermine, which are seen at elevated levels in some victims of cancer, were separated on a Technicon (The Technicon Company Chauncey, NY) TSM Amino Acid Analyzer packed with an 8% divinylbenzene-co-polystyrene sulfonated resin with post-column ninhydrin detection.111 Amines such as ethanolamine, noradrenaline, hexamethylene diamine, methoxytryptamine, spermine, and spermidine were separated from amino acids on a DC-4A cation exchange resin.112 A similar approach, using a Beckman Model 121M amino acid analyzer equipped with an AA-20 column, was also successful.113 A Polyamin-pak strong cation exchange column (JASCO) was eluted with a citrate buffer for the detection of putrescene, spermine, cadaverine, and 1,5-diaminohex-ane from rat thymus.114 A post-column o-phthaldehyde detection system was used. [Pg.230]

CE has been used for the analysis of anionic surfactants [946,947] and can be considered as complementary to HPLC for the analysis of cationic surfactants with advantages of minimal solvent consumption, higher efficiency, easy cleaning and inexpensive replacement of columns and the ability of fast method development by changing the electrolyte composition. Also the separation of polystyrene sulfonates with polymeric additives by CE has been reported [948]. Moreover, CE has also been used for the analysis of polymeric water treatment additives, such as acrylic acid copolymer flocculants, phosphonates, low-MW acids and inorganic anions. The technique provides for analyst time-savings and has lower detection limits and improved quantification for determination of anionic polymers, compared to HPLC. [Pg.278]

Polystyrene Sulfonic Acid (Sodium), 70 kDa 1.0-5.0 Polysciences, Warrington, PA... [Pg.7]

Polymer Media Polymaleic Anhydride Poly Acrylic Acid Polyvinyl Phosphonic Acid Polyvinyl Sulfonic Acid Polystyrene Sulfonate Tripoly Phosphate... [Pg.28]

The first section, Chemical Reactions on Polymers, deals with aspects of chemical reactions occurring on polymers—aspects relating to polymer size, shape, and composition are described in detail. One of the timely fields of applications comprises the use of modified polymers as catalysts (such as the immobilization of centers for homogeneous catalysis). This topic is considered in detail in Chapters 2, 3, 8, 9, and 11 and dealt with to a lesser extent in other chapters. The use of models and neighboring group effect(s) is described in detail. The modification of polymers for chemical and physical change is also described in detail in Chapters 2 (polystyrene) 4 (polyvinyl chloride) 5 (polyacrylic acid, polyvinyl alcohol, polyethyleneimine, and polyacrylamide) 6 (polyimides) 7 (polyvinyl alcohol) 8 (polystyrene sulfonate and polyvinylphosphonate) 10 (polyacrylamide) and 12 (organotin carboxylates). [Pg.505]

Proton conductivity as a function of lEC for ETFE-g-PSSA = polyethylenetetrafluoroethylene-gra/t-polystyrene sulfonic acid, BAM membrane = substituted poly(trifluorostyrene) sulfonic acid, SPEEK = sulfonated poly(ether ether ketone) and Nafion. (From Peckham, T. J. et al. 2007. Journal of Materials Chemistry 17 3255-3268, and Dolye, M. et al. 2001. Journal of Physical Chemistry B 105 9387-9394.)... [Pg.111]

Yu, J., Yi, B., Xing, D., Liu, R, Shao, Z. and Fu, Y. 2003. Degradation mechanism of polystyrene sulfonic acid membrane and application of its composite membranes in fuel cells. Physical Chemistry Chemical Physics 5 611-615. [Pg.176]

Particulates consisting of porous, particulate ion exchange resins with various paramagnetic ions (Cu, Fe " , Fe " , Mn " ", and Gd " ") bound to their surface were investigated by Braybrook et al. (93,94). The resins used were sulfonated polystyrene, iminodiacetic acid substituted polystyrene and sepharose activated with l,4-bis(2,3-epoxypropoxy) butane and substituted with iminodiacetic acid. [Pg.281]

Similarly to the hydrolysis of sucrose, acid exchanged resins can be utilized, in one case to give 75% hydrolysis of triglycerides after six hours at 155 °C. It was shown that the Brondsted acid sites catalyze the hydrolysis reaction, which was performed in the liquid phase with continuous steam injection.The same authors reported that polystyrene sulfonic cation-exchange resin, loaded with 13% of the superacid H3M0, gave 74.5% hydrolysis of palm oil at 155 °C in a batch reactor also operated with steam injection. [Pg.24]

In a related application, polyelectrolyte microgels based on crosslinked cationic poly(allyl amine) and anionic polyfmethacrylic acid-co-epoxypropyl methacrylate) were studied by potentiometry, conductometry and turbidimetry [349]. In their neutralized (salt) form, the microgels fully complexed with linear polyelectrolytes (poly(acrylic acid), poly(acrylic acid-co-acrylamide), and polystyrene sulfonate)) as if the gels were themselves linear. However, if an acid/base reaction occurs between the linear polymers and the gels, it appears that only the surfaces of the gels form complexes. Previous work has addressed the fundamental characteristics of these complexes [350, 351] and has shown preferential complexation of cationic polyelectrolytes with crosslinked car-boxymethyl cellulose versus linear CMC [350], The departure from the 1 1 stoichiometry with the non-neutralized microgels may be due to the collapsed nature of these networks which prevents penetration of water soluble polyelectrolyte. [Pg.29]

A palladium(II)-exchanged polystyrene sulfonic acid resin (Dowex 50W, H form) catalyzes the oxidation of 2-methylnaphthalene with 60% aqueous H2O2 (reaction 27), affording 2-methyl-l,4-naphthoqu1none (menadione) in 55-60% yield at 90-97% conversion. 3 Menadione is a commercially important vitamin K intermediate and these results compare favourably with those obtained in existing industrial processes that employ stoichiometric quantities of chromium trioxide in sulfuric acid. [Pg.47]

Ainberlyst-type catalysts were as active as and more selective than the best homogeneous catalyst, II2SO4. Amberlyst 15 and 3G are macroreticular type polystyrene sulfonic acid resins partially cross-linked with divinylbenzene. The absence of the N—benzyl product when solid acid catalysts were employed suggests the possibility that the reaction could be carried out in a single step. It is also expected to provide all the aforementioned advantages of solid catalysts over liquid catalysts. [Pg.499]

To increase the surface area of the stationary phase for CEC separation, a collocated monolithic support structure (COMOSS) was constructed in a Si chip. A polystyrene-sulfonic acid stationary phase was then immobilized [349]. Design of the COMOSS required that the combined cross sectional area at the column head to be the same at any point in the inlet distributor [644]. A study for the reduction of band broadening in COMOSS was also reported [645]. [Pg.164]

U21 Gates, B. C., Schwab, G.-M. The Dehydration of Formic Acid Catalyzed by Polystyrene Sulfonic Acid. J. Catalysis 15, 430 (1969). [Pg.37]

The pioneer work in this field was carried out on polystyrene-supported acid catalysts [161]. Thereafter, several works on the use of sulfonic, strong acidic cation exchangers as acid catalysts were reported for alkylation, hydration, etherification, esterification, cleavage of ether bonds, dehydration, and aldol condensation [162,168-171], Besides, industrial applications of these materials were evaluated with reactions related to the chemistry of alkenes, that is, alkylation, isomerization, oligomerization, and acylation. [163,169], Also, Nation, an acid resin which has an acid strength equivalent to concentrated sulfuric acid, can be applied as an acid catalyst. It is used for the alkylation of aromatics with olefins in the liquid or gas phases and other reactions however, due to its low surface area, the Nation resin has relatively low catalytic activity in gas-phase reactions or liquid-phase processes where a nonpolar reactant or solvent is employed [166],... [Pg.462]

An excellent example where a capsid virus has been given a new supramolecular application can be found in the work of Nolte who took an icosahedral capsid virus, cowpea chloritic mottle virus (CCMV) and used it as a nanoreactor for polymer synthesis [30], Natural CCMV spontaneously assembles in acidic aqueous solution and disassembles in basic solution. The capsid contains pores open at pH 5 to release RNA into the host. Once the RNA leaves, the empty capsule is left. The Nolte group was able to assemble the subunits around polystyrene sulfonate with a mass of 9.9 kDa but the resulting structure had a different morphology to the natural system. Indeed, capsules formed around polymers with masses between 2 and 85 kDa but not around those with masses above 100 kDa. This raised the question of the potential for polymers to form within a capsid but to test the possibility a mixture of botanical, biological and chemical approaches was needed. [Pg.107]


See other pages where Polystyrene sulfonic acid , -sulfonates is mentioned: [Pg.403]    [Pg.1398]    [Pg.54]    [Pg.322]    [Pg.253]    [Pg.430]    [Pg.7]    [Pg.306]    [Pg.104]    [Pg.354]    [Pg.350]    [Pg.1350]    [Pg.67]    [Pg.654]    [Pg.32]    [Pg.654]    [Pg.131]    [Pg.377]    [Pg.214]    [Pg.506]    [Pg.509]    [Pg.509]    [Pg.511]    [Pg.517]    [Pg.523]    [Pg.3082]    [Pg.642]    [Pg.144]    [Pg.412]   
See also in sourсe #XX -- [ Pg.198 ]




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Alkylated polystyrene-supported sulfonic acid

Interaction between polystyrene sulfonic acid)

Ion exchange materials polystyrene sulfonic acid resins

Poly(3,4-Ethylenedioxythiophene) Polystyrene Sulfonic Acid

Polyacrylonitrile polystyrene sulfonic acid

Polystyrene sulfonate

Polystyrene sulfonated acid

Polystyrene sulfonated acid

Polystyrene sulfonation

Polystyrene sulfonic acid

Polystyrene sulfonic acid

Polystyrene sulfonic acid beads

Polystyrene sulfonic acid membrane

Polystyrene supported sulfonic acid

Sulfonated polystyrene

Sulfonated polystyrene sulfonic acid)

Sulfonated polystyrene sulfonic acid)

Sulfonated polystyrene sulfonic acid) membranes

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