Styrene-divinyl benzene polymers

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. 

HPLC of aqueous simulants or water using an ion exclusion column (styrene divinyl benzene polymer with sulfonated [cationic] ion-exchange groups). Derivitisation with fluorescamine, 4-phenylspiro-[furan 2-(3),... 

Q,C,atropine, acridine.ephe-drine,opium alkaloids,reserpine,strychnine, yohimbine Separation on styrene-divinyl benzene polymer (Table 8.4) - Hitachi gel 3010, 10 pm 220x4.6 ACN-0.02M NH,0H(3 2) ACN-0.02M tetrabutyl-ammoniumhydroxide (3 7), (3 2) 44... 

F. D Alelio, of General Electric Co., prepared the first styrene-divinyl benzene polymers (U.S. Patents 2,340,110 and 2,340,111). These allowed various porosities of material to be prepared and provided a backbone for various types of cation and anion exchange groups to be added. (See the reaction on p. 271.)... 

One type of anion exchange column used for nonsuppressed applications is the ION-20 from Interaction Co. It is a quaternary ammonium group on a styrene-divinyl benzene polymer in the form of 9 pm particles with an exchange capacity of 100 peq/g. Figure 24-14 is an example of a multiple anion separation. 

The two insoluble compounds precipitate and are removed from the water by filtration. Thus by the successive usage of cation and anion-exchange resins sodium chloride could be removed from water. An example of a cation-exchange resin is sulfonated styrene-divinyl-benzene polymer and an anion-exchange resin can be made by chloromethylating styrene-divinyl copolymer and replacing the chlorines with tr i me thy1ami ne. 

Ouinone-impreg-nated styrene-divinyl benzene polymers... 

Alcohols are also analyzed by LC in most cases the choice of the column falls on an ionic-exchange resin of the styrene-divinyl benzene polymer type, to which has been linked a functional group of the sulfonic type in the form or with another suitable cation. Since the separation of alcohols is performed very often together with other analytes, such as organic acids and sugars, the choice of the type of detector also takes into account their chemical-physical properties. Usually, the choice is the UV detector, the refractive index detector, or the electrochemical detector (EC). The use of LC allows the determination of less volatile alcohols such as glycerol in wine and beer, which could be difficult to analyze by GC. 

The resins are based on standard styrene/divinyl benzene polymers with weakly acidic functionality. The first resins developed borrowed directly from chelation (L. chela = claw) chemistry. Compounds such as ethylene diamine tetraacetic acid (EDTA) when ionized have two monovalent anionic end groups that do in fact have a claw-like structure. They have a powerful affinity for divalent cations such as calcium and magnesium. When iminodiacetate functionality is built into a polymer, it provides... 

Four quinolone residues (flumequine, nalidixic acid, oxolinic acid, and piromidic acid) were extracted from catfish muscle and separated on a 45 C styrene divinyl benzene polymer column (A = 280 nm for piromidic acid 325 nm, ex, 365 nm, em for all others) using a 720/120/60 water/THF/acetonitrile with 0.213 mL H3PO4 mobile phase [842]. Elution was complete in 17 min. A linear range of 10-200 ng/g sample and a quantitation limit of around 5 ng/g were reported. 

Aromatic electrophilic substitution is used commercially to produce styrene polymers with ion-exchange properties by the incorporation of sulfonic acid or quaternary ammonium groups [Brydson, 1999 Lucas et al., 1980 Miller et al., 1963]. Crosslinked styrene-divinyl-benzene copolymers are used as the starting polymer to obtain insoluble final products, usually in the form of beads and also membranes. The use of polystyrene itself would yield soluble ion-exchange products. An anion-exchange product is obtained by chloromethylation followed by reaction with a tertiary amine (Eq. 9-38) while sulfonation yields a cation-exchange product (Eq. 9-39) ... 

The sorbents, Chromosorb 102 and XAD-2, which are styrene-divinyl benzene cross-linked porous polymers, proved to be most useful in our studies. Capacity of the sorbent sampling tubes was not a problem with the pesticides we studied since most were not extremely volatile. Sampling humid atmospheres of the pesticides also did not affect the sorbent capacity since these porous polymers are hydrophobic. 

PCB ADSORPTION. PCBs are practically insoluble in water because of a very weak solute-water interaction PCBs will have a strong solute-polymer interaction if a polymer such as styrene-divinyl-benzene is used water will have a weak interaction with styrene-divinylbenzene thus, conditions for effective adsorption are present. Therefore, large volumes of water can be passed through a column packed with a styrene-divinylbenzene polymer, and the PCBs will be adsorbed (partitioned) efficiently. 

Functionalization of crosslinked polymers by Mannich reaction" includes mainly polystyrenes and polyacrylics such as styrene/divinyl benzene copolymers 537-539114-117 gpjj acrylic ester/divinyl benzene copolymers 540, respectively." These materials are involved in the reaction as substrate (539)" or, more frequently, as amine reagent (sec also Fig. 163, Chap. Ill) when the crosslinked product, containing amino groups, is allowed to react with phosphorous acids (537,538, and 540). Thus, chelating properties are assumed by the resins. 

The advantages of the ion-exchange resins, a common one being a sulphon-ated styrene-divinyl benzene cross-linked polymer, were claimed to be as follows ... 

No.caf.Dmethphan Antitussives, Separation on porous polymer Styrene-divinyl benzene 500x5 expectorants, resins methyl methacrylate co- or antihistaminics polymer, substituted 500x3 various others with hydroxymethyl groups Me0H-NH.0H(99 1) MeOH-H2D-NH4OH(95 5 l) 59... 

Porous styrene-divinyl benzene co-polymer no de- MeOH-NH.OH tails available 52,58... 

In reversed phase liquid chromatography (RPLC) silylated silicas are preferred. The surface of these silicas is covered with chemically bonded non-polar groups such as alkyl chains or polymeric layers (Chapter 3.2.3). Silica modified with medium polar groups such as cyano, diol or amino might be used in NP as well as RP mode. Alternatively, cross-linked polymers such as hydrophobic styrene divinyl benzene-copolymers can be used (Chapter 3.2.4). Polymer packings show stability in a pH range 2-14 while silica based packings show limited stability for pH > 7. 

Macroporous styrene-divinyl benzene (S-DVB) copolymers are widely used as supports for chemical reactions (1). The surface area, pore volume, and pore size of these materials can be manipulated by a judicious choice of reaction conditions (2). It is recognized that reaction cosolvent and the ratio of monomer to cosolvent are Important variables and considerable speculation has been offered regarding the relationship between polymerization conditions and polymer morphology (3). On the basis of these studies a model has emerged to account for macroporosity in these materials (4). The continuous or gel phase is found to consist of aggregated microspheres. The macropores are defined by voids created by these aggregated raicrospheres. 

In a separate series of experiment commercially available styrene divinyl benzene copolymer (XAD-8) was taken as a polymer support. 

Other o-nitrophenol-containing resins have been prepared with the aim of increasing the distance between the reactive center and the macromolecular backbone, which should accelerate the active ester formation by achieving an easier approach of the reagents. Thus, the Friedel-Crafts alkylation of styrene-divinyl-benzene copolymer with 4-hydroxy-3-nitrobenzyl chloride promoted by aluminium trichloride gave 4-hydroxy-3-nitrobenzylated polystyrene (70) (approximately 30% of the aromatic rings of the polymer were substituted according to elemental... 

The chosen polymer support influences the reaction as well. Various polymer supports are described above. Studies of the hydrogenation of 2-propen-2-ol with Pd(0) catalysts showed interesting efficiency and selectivity differences dependant on the polymer resin chosen. Zharmagambetova et al. [16] studied three different organic polymer supports for Pd(0) nanoclusters and compared them to the inorganic A1203. Organic polymers included poly-2-vinlypyridine (PVP), cellulose and styrene-divinyl benzene (STY-DVB) copolymer. The cellulose and STY-DVB... 

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