Sulfonated polystyrene-divinylbenzene

The ion movement can be controlled by ion exchange or ion transfer membranes, thin sheets of cross-linked organic polymers with ion exchange properties—for example, sulfonated polystyrene-divinylbenzene polymers. Both cation-permeable and anion-permeable membranes are available and have been described (3, 9). To achieve demineralization, these membranes are spaced alternately between a cathode and an anode which introduce direct current. The compartment between each pair of membranes is filled with a saline water. The resulting ion motion is controlled by the membranes, so that one set of compartments—for example, the even-numbered compartments—lose ions and the odd-numbered compartments gain ions. The product from the ion-losing cells is collected and comprises electrically demineralized water. 

The acidity of these resins, however, increases significantly by treating them with Lewis acid halides. Gates and co-workers151 153 have prepared a superacid catalyst from AICI3 and beads of macroporous, sulfonated polystyrene-divinylbenzene. The... 

Aldonic, uronic, and ascorbic acids, lactones, and N-acetylated amino sugars were separated on sulfonated polystyrene-divinylbenzene, a strong polyanion exchanger (Wheaton and Bauman, 1953). This method is adaptable to neutral carbohydrates without complexation or adsorption, by immersion in strong alkali to ionize the hydroxyl groups (ion chromatography). 

Ion exchange resins (methacrylic acid, sulfonated polystyrene/divinylbenzene) Polyacrylic acid (Carbopol) Poly(MMA/MAA)... 

Table 4-3. Elution order of some organic acids which can be analyzed by ion-exclusion chromatography on a totally sulfonated polystyrene/divinylbenzene-based cation exchanger.

Hydrophobicity in an ion-exchange column can have both positive and negative attributes. An attractive feature is that it can change the selectivity and increase the resolution between some species. The negative aspect of columns that are both charged and hydrophobic is that they often show lower protein recovery. An extreme case is the use of sulfonated polystyrene-divinylbenzene columns on which recovery of proteins is often very poor. 

Latex-based anion exchangers are comprised of a surface-sulfonated polystyrene/divinylbenzene substrate with particle diameters between 5 pm and 25 pm and fully aminated, high-capacity porous polymer beads made of poly-vinylbenzyl chloride or polymethacrylate, which are called latex particles. The latter have a much smaller diameter (about 0.1 pm) and are agglomerated to... 

The first type of hydrocarbon membrane for fuel cell applications was the sulfonated polystyrene-divinylbenzene co-polymer membranes equipped for the power source in NASA s Gemini space flights, but the sulfonated polystyrene had low chemical stability for long-term applications, because the proton on the tertiary carbons and benzylic bonds are easily dissociated in an oxygen environment forming hydroperoxide radicals. Since a styrene monomer is easily co-polymerized with other vinyl monomers via radical polymerization methods, various styrenic polymers were researched intensively. Two commercial polystyrene-based/related membranes are available BAM (Ballard), and Dais Analytic s sulfonated styrene-ethylene-butylene-styrene (SEBS) membrane. Dais membranes are produced using... 

Note-. These imply a negatively charged sulfonated polystyrene-divinylbenzene copolymer, the... 

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