Divinyl benzene copolymers

Polymetric matrix Polydiallyldimethylammonium bromide [9] Polypyrrole [10[ Poly (MA -dimethyb-S -pyrrolidinium bromide [11J Styrene-divinyl benzene copolymers [4] Polyacrylamide [12]... 

Distribution of ortho-, meta-, and para-isomers in the divinyl benzene copolymer... 

Since the introduction of gel-permeation chromatography (GPC) in the 1960 s, there have been tremendous advances in polymer gel size-exclusion column technology. Polystyrene-divinyl benzene copolymer gels, and the techniques by which they are packed into columns, have improved to the point where commercial columns exhibit up to 50,000 plates/meter. These lO-ym gels are sufficiently rugged to permit flow rates of up to 3.0 ml/minute... 

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) ... 

Drinking water Preconcentration onto 5 pm C18-silica or 7 pm polystyrene-divinyl benzene copolymer with subsequent backflush onto analytical HPLC column. RP-HPLC/UV (254 mn) 0.03-0.06 pg/L (ppb) 91 ( 10% RSD) at sample volumes up to 300 mL Driss et al. 1993... 

Nonpolar interactions (hydrophobic) typical octadecyl-modified silica, polystyrene-divinyl benzene copolymers, or carbon-based sorbent. 

Styrene divinyl benzene copolymers (PS-DVB), either porous or rigid, are stable over the whole pH range. Calculated In ku, values on these sorbents are higher than those on C,8. Consequently, moderately polar compounds that are not retained by Cl8 silica are more readily concentrated on these sorbents. 

Porapak-Q 250 Ethylvinyl benzene-divinyl benzene copolymer 0.35 500-700... 

Porapak-QS 250 Ethylvinyl benzene-divinyl benzene copolymer 625 525 565 445 Similar to Porapak-Q at lower operating temperatures, but useful for higher-molecular-weight solutes Silanized Porapak-Q reduces tailing of high-polarity compounds condition at 250° C... 

Porapak-PS 250 Styrene-divinyl benzene copolymer Similar to Porapak-P Silanized Porapak-P condition at 250° C... 

J. W. Kelly and J. T. Stewart, Separation of selected beta lactam antibiotic epimers on gamma cyclodextim ion exchange ethylvinyl benzene divinylbenzene copolymer and poly(styrene-divinyl benzene) copolymer stationary phases, J. Liquid Chromatogr., 14 2235(1991). 

The plastic separating column was 7.5 x 100mm and was packed with a cation exchange resin in the H+ form TSK SCX 5pm (polystyrene divinyl benzene copolymer-based material with a high cation exchange capacity). 

The majority of LC separations in CW analysis use stationary phases that separate analytes on the basis of hydrophobic interactions under reversed phase conditions, that is, they retain hydrophobic analytes more strongly than polar ones. The most commonly used stationary phases are based on 3-7 (commonly 3 or 5) micron-sized silica particles coated with bonded alkyl phases, or polymeric particles such as styrene-divinyl benzene copolymer. Bonded reversed phase silicas in decreasing order of hydrophobicity are Cl8 (ODS), octyl (C8), phenyl,... 

Huber, C., Oefner, P., and Bonn, G. (1992). High-resolution liquid chromatography of oligonucleotides on non-porous alkylated-styrene-divinyl benzene copolymers. Anal. Biochem. 212, 351-358. 

Gel-Permeation Chromatography. A Water Associates HPLC with four Shodex GPC-AD-802S columns was used with dimethylformamide at a flow rate of 1 mL/minute. The gel is polystyrene-divinyl benzene copolymer and has exclusion limit of 8,000 by polystyrene molecular weight. Sample injection... 

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. 

Aramaki et al.15 studied the chromatographic behaviour of some alkaloids on a macroporous styrene-divinyl benzene copolymer (see Fig.8.6 and Table 8.4). The influence of changes in the mobile phase on the retention was studied. 

Column Hitachi Gel 3010 (macroporous styrene-divinyl benzene copolymer), 10 ym (220x4.6 mm ID), mobile phase acetonitrile - water (6 4) containing 0.02 M ammonia, flow rate 2 ml/min, detection UV 254 nm. (see also Table 8.4). Peaks 1, morphine 2, codeine 3, papaverine 4, yohimbine 5, noscapine 6, reserpine.(reproduced with permission from ref. 43, by courtesy of the American Chemical Society)... 

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. 

Nonaka, T. Uemurra, Y. Kurihara, S. Preparation of the resins containing quaternary ammonium groups from glycidyl methacrylate-1,4-divinyl-benzene copolymer beads and antibacterial activity of the resins. Nippon Kagaku Kaishi 1994, 12, 1097-1106 (written in Japanese). 

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