Anion-exchange polymer

Of greatest interest for PAN modification with the purpose of obtaining strongly basic anion-exchange polymers can be the quartemary salts of vinyl pyridines. 

Note 3 Depending on which ion can be exchanged, the polymer is referred to as an anion exchange polymer or cation exchange polymer. 

Adsorption of an ionic pollutant was increased by modifying the surface electric charge of Ti02 particle. P043- and nafion (anion exchange polymer) attached to Ti02 promoted the adsorption of cationic pollutant and in turn accelerated its degradation (Fig. 9.18).37)... 

Iron-loaded anion-exchange polymer Cumbal and Sengupta (2005), Creenleaf, Fin and Sengupta (2006)... 

Cumbal and Sengupta (2005) produced an effective arsenic removal system by dispersing high-surface area iron (oxy)(hydr)oxide nanoparticles within a base (anion exchange) polymer for permeable matrix support (Table 7.1). The polymer consisted of a quaternary ammonium functional group within a styrene-divinylbenzene matrix. The addition of the nanoparticles improved arsenic removal when compared with the polymer alone. 

LPEI was converted to a cationic polyelectrolyte by polymer-analogous methyla-tion [33]. The soluble anion exchange polymer had trimethyl ammonium moities in the side chain ... 

Pickup PG (1990) Alternating current impedance study of a polypyrrole-based anion-exchange polymer. J Chem Soc Faraday Trans 86 3631-6... 

These cationic and anionic exchange polymers require that the mobile ions be well solvated with a polar solvent such as water. For applications such as the electrolyte phase in lithium batteries, an ionic conducting polymer is needed in which ionic mobility is obtained without the ions being solvated by water or some other solvent. This has been... 

For cation systems, the suppressor membranes are anion exchange polymers, which allow anions to pass freely, but exclude cations. Dilute acids such as HCl are used in the mobile phase. In the suppressor, chloride counterions are replaced by highly conductive OH ions, neutralizing the acidic mobile phase. Tetrabutylammonium hydroxide is used as the regenerant because it is excluded from the anion exchange membranes."... 

Molybdic and phosphomolybdic acids bound to 60 nm colloidal anion exchange polymer catalyse the epoxidation of cyclooctene with 90% selectivity [41-42]. Only 12% epoxide is formed in the absence of colloidal particles. 

Definition A synthetic anion exchanged polymer in which quaternary ammonium groups are attached to a copolymer of styrene and divinylbenzene Properties Wh. to buff-colored fine powd. odorless to si. amine odor insol. in water, ethanol, chloroform, ether, benzene, org. soivs. stable to 150 C... 

Yang CC (2012) Alkaline direct methanol fuel cell based on a novel anion-exchange polymer membrane. J Appl Electrochem 42 305-317... 

Cosnier, S., A. Deronzier, J.C. Moutet, and J.F. Roland (1989). Alkylammonium and pyridinium group-containing polypyrroles, a new class of electronically conducting anion-exchange polymers. 7. Electroanal. Chem. 271, 69-81. 

In this cationic, anion-exchanger polymer, the following redox anions have typically been incorporated and investigated ... 

Mamlouk M, Wang X, Scott K, Horsfall J, Williams C (2011) Characterization and application of anion exchange polymer membranes with non-platinum group metals for fuel cells. Proc Inst Mech Eng A J Power Energy 225(2) 152-160... 

Mamlouk M, Kumar SM, Gouerec P, Scott K (2011) Electrochemical and fuel cell evaluation of Co based catalyst for oxygen reduction in anion exchange polymer membrane fuel cells. J Power Sources 196 7594—7600... 

Fe(CN)g] in anion-exchange polymers, typically in Tosflex [12, 18]. To the same purpose, several examples are also reported involving Nafion for the anchoring of positively charged metal complexes [19] or of organic species [20]. 

In principle, three different electrolyte types can be distinguished liquid flow electrolytes (e.g., potassium hydroxide, sodium hydroxide, or their mixtures), immobihzed electrolytes (i.e., the Hquid electrolyte is fixed in a matrix or a gel), and anion-exchange polymer electrolytes (e.g., sohd polymer electrolytes in PEFCs as described above). 

Hydroxide-Selective Grafted Polymers Dionex (now part of Thermo Fisher Scientific) also introduced a hydroxide-selective, surface-functionalized EVB/DVB resin featuring a covalently attached anion-exchange polymer under the trade... 

Kim YS (2011) Resonance-stabihzed anion exchange polymer electrolytes. US DOE hydrogen and fuel cells program and vehicle technologies program... 

Alkaline Membrane Fuel Cells, Membranes, Fig. 4 Scheme of a simplified synthesis of a polyethylene-based anion exchange polymer with quaternary ammonium functional groups... 

Kim YS (2010) Resonance-stabilized anion exchange polymer electrolytes. In Annual merit review and... 

Kim DS, Laboiniau A, GuIvct MD, Kim YS (2011) Guanidinium-fhnctiOTialized anion exchange polymer electrolytes via activated fluorophenyl-amine reaction. Chem Mater 23 3795-3797. doi 10.1021/cm2016164... 

Solid polymer electrolytes on the basis of a polymer cation exchange membrane in H" -foim or an anion exchange polymer membrane in OH -form can be considered as quasi-aqueous electrolytes, whereby the water is absorbed in the phase separated ionic nano morphology of the respective material. This nano morphology forms imiic pathways through the polymeric membrane connecting the two fuel cell electrodes. 

Anion-exchange polymers that contain methacrylate, ester, amide, or other carbonyl (C = O double bond) functional groups show low stabilities in alkali as these functional groups are highly reactive to nucleophiles such as OH. ... 

It is essential that a solubilized form of an alkaline anion-exchange polymer be developed to improve the interface between the electrodes and the AEM electrolyte. Success in this effort will decrease MEA resistances. A water-based soluble form which can be rendered water insoluble when cast would be preferred, as there are safety concerns (primarily with industrial scale production) about using organic solvents near finely dispersed (pyrophoric) metal catalysts (unsupported or supported on carbon). 

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