Polystyrene-divinylbenzene matrix

Polystyrene and its divinylbenzene cross-linked copolymer have been most widely exploited as the polymer support for anchoring metal complexes. A large variety of ligands containing N, P or S have been anchored on the polystyrene-divinylbenzene matrix either by the bromination-lithiation pathway or by direct interaction of the ligand with C1-, Br- or CN-methylated polystyrene-divinyl-benzene network [14] (Fig. 7). 

Coloured complexes of a number of 3d metal salts with bipyridylamine previously anchored on partially cfaloromethylated polystyrene-divinylbenzene matrix have been reported by Hendricker and Kratz [17] and by Biswas and Mukherjee [18] (Fig. 9). 

In a more recent work Ito [101] has described a simple and highly sensitive ion chromatographic method with ultraviolet detection for determining iodide in seawater. A high-capacity anion exchange resin with polystyrene-divinylbenzene matrix was used for both preconcentration and separation of iodide. Iodide in artificial seawater (salinity, 35 % ) was trapped quantitatively (98.8 0.6%) without peak broadening on a preconcentrator column and was separated with 0.35M sodium perchlorate+ 0.10M phosphate buffer (pH 6.1). On the other hand, the major anions in seawater, chloride and sulphate ions, were partially trapped (5-20%) and did not interfere in the determination of iodide. The detection limit for iodide was 0.2pg L 1 for 6mL of artificial seawater. This method was apphed to determination of iodide (ND-18.3pg L ) and total inorganic iodine (I +I03 -I, 50.0-52.7pg L 1) in seawater samples taken near Japan. 

Kauspediene D, Kazlauskiene E, Cesuniene R, Gefeniene A, Ragauskas R, Selskiene A. Removal of the phthalocyanine dye from acidic solutions using resins with the polystyrene divinylbenzene matrix. Chemija 2013 24(3) 171-81. 

In addition to true ion exchange, other interactions can take place between the sample solutes and the resin. Adsorption is one of the commonest of these interactions. For example, the benzoate anion appears to be adsorbed somewhat by the polystyrene-divinylbenzene matrix of organic ion exchangers. This may be due to an attraction of the n electrons of the aromatic polymer for the benzoate. Benzoic... 

Ion-retardation resins, which consist of acrylic acid polymerized inside a strong anion-exchange resin on a polystyrene divinylbenzene matrix [30], are also effective for removal of SDS from proteins. Passage of a protein-SDS complex through the resin results in complete retention of SDS and elution of protein with 80-90% recovery [31]. The capacity of the resin for SDS is more than 2.2mg/g, which effectively reduces the SDS level to less than one molecule of SDS per protein molecule. Because SDS binds tenaciously to the resin, it cannot be removed and the resin must be discarded after use. In the presence of buffers, adsorption of SDS by an ion-retardation column is reduced, resulting in incomplete removal of detergent from the protein. This can be circumvented by prior removal of buffer by SEC or, more conveniently, by the addition of a few grams of size exclusion gel to the head of the ion-retardation resin bed to retard the buffer [4]. 

The last column with it" form of a strong cation exchanger (column 5) gets an acidic mixture of five amino acids eluted from column 3 Arg, His, Lys, Phe, and Tyr. The process is performed in the way to achieve a chromatographic separation of these products. One has to note that the sequence of chromatographic elution does not reflect ionizing properties of these amino acids. Different retention of different substances could be explained by additional nonionic interactions between these products and polystyrene-divinylbenzene matrix of the polymer. 

Gel permeation ehromatography (GPC)/normal-phase HPLC was used by Brown-Thomas et al. (35) to determine fat-soluble vitamins in standard referenee material (SRM) samples of a fortified eoeonut oil (SRM 1563) and a eod liver oil (SRM 1588). The on-line GPC/normal-phase proeedure eliminated the long and laborious extraetion proeedure of isolating vitamins from the oil matrix. In faet, the GPC step permits the elimination of the lipid materials prior to the HPLC analysis. The HPLC eolumns used for the vitamin determinations were a 10 p.m polystyrene/divinylbenzene gel eolumn and a semipreparative aminoeyano eolumn, with hexane, methylene ehloride and methyl tert-butyl ether being employed as solvent. 

Reversed-phase chromatography employs a nonpolar stationary phase and a polar aqueous-organic mobile phase. The stationary phase may be a nonpolar ligand, such as an alkyl hydrocarbon, bonded to a support matrix such as microparticulate silica, or it may be a microparticulate polymeric resin such as cross-linked polystyrene-divinylbenzene. The mobile phase is typically a binary mixture of a weak solvent, such as water or an aqueous buffer, and a strong solvent such as acetonitrile or a short-chain alcohol. Retention is modulated by changing the relative proportion of the weak and strong solvents. Additives may be incorporated into the mobile phase to modulate chromatographic selectivity, to suppress undesirable interactions of the analyte with the matrix, or to promote analyte solubility or stability. 

Polystyrene divinylbenzene Ion-exchange resins are commonly manufactured from a copolymer of styrene (Figure 4.8) and divinylbenzene (Figure 4.9). The divinylbenzene content in the matrix determines the degree of cross-linking. So, 5% mol divinylbenzene... 

Titanium complexes containing polymerizable vinyl-substituted aryloxide ligands have been employed to prepare polystyrene/divinylbenzene-based polymers that incorporate Ti aryloxide fragment into the matrix 446 Such materials have been used to catalyze Diels-Alder reactions with high diastereoselectivity and at rates only three to five times slower than the corresponding homogeneous reactions. ... 

Another possible source of a phosphorus pendant group was [(2-dihydro grarsinoylphenylamino)methyl]phosphonic acid, which was used to modify the Amberlite XAD-16 polymeric matrix. Subramanian et al. also modified the polystyrene-divinylbenzene copolymer beads (Amberlite XAD-16) by anchoring 6,6,6-trifluoro-2,5-dioxo-4-(thiophene-2-carbonyl)he yl-phosphinic acid in its matrix in order to obtain a new chelating ion-exchange multidentate grafted polymer (Scheme 11.9). ... 

The column medium is a polystyrene-divinylbenzene polymer with octylphenyl-N,N-diisobutyl carbamo-ylphosphine oxide extractant adsorbed on the hydrophobic polymer matrix. The carbamoylphosphine oxide functional group is an avid chelator for actinides in 0.16 M or higher concentration nitric acid, whereas alkali and alkaline earth metals are poorly bound. Lanthanides are only retained on the column at much higher nitric acid concentrations (>6 M). Therefore, even these are eliminated from the final matrix under the rinse conditions employed. A very hard base anion ligand is necessary to compete effectively with the carbamoylphosphine oxide ligands and elute actinides, including uranium, in a small volume. In Protocol 1, the fluoride ion from dilute hydrofluoric acid (HF) was chosen for this purpose. 

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