Styrene divinylbenzene and

Structures of styrene, divinylbenzene, and a styrene-divinylbenzene co-polymer modified for use as an ion-exchange resin. The ion-exchange sites, indicated by R, are mostly in the para position and are not necessarily bound to all styrene units. 

The monomers commonly used for the preparation of polymer monoliths are either hydrophobic, for example, styrene/divinylbenzene and alkyl methacrylates, or hydrophilic, for example, acrylamides. The polymerization is usually accomplished by radical chain mechanisms with thermal or photochemical initiation, as detailed in the reviews (Eeltink et al., 2004 Svec, 2004a and b). Internal structures of polymer monoliths are described to be corpuscular rather than spongy this means through-pores were found to be interstices of agglomerated globular skeletons as shown in Fig. 7.1 (Ivanov et al., 2003). Porosity is presumably predetermined by the preparation... 

Kureshy developed a polymer-based chiral Mn-salen complex (Figure 21). Copolymerization of styrene, divinylbenzene, and 4-vinylpyridine generated highly cross-linked (50%) porous beads loaded with pyridine ligands at 3.8 mmol g-1. Once the polymer was charged with the metal complex catalyst, enantioselective epoxidation of styrene derivatives was achieved with ee values in the range 16 46%. 79... 

Abraham, M. H., H. C. Chadha, R. A. E. Leitao, R. C. Mitchell, W. J. Lambert, R. Kaliszan, A. Nasal, and P. Haber, Determination of solute lipophilicity, as log P (octanol) and log P (alkane) using poly(styrene-divinylbenzene) and immobilized artificial membrane stationary phases in reversed-phase high performance liquid chromatography , J. Chromatogr. A, 766, 35-47 (1997). 

The limited applications of Tenax and polyurethanes can be explained from theoretical considerations discussed earlier and because of practical problems that are more severe than those encountered in the use of the styrene-divinylbenzene and acrylate polymers. 

As films are used e.g. the polymerization product of ethylbenzene and divinylbenzene (33) the copolymer of styrene and butadiene (755) the copolymer of styrene and butadiene mixed with polyethylene (157) a vulcanized or cyclized copolymer of an aromatic vinylcompound and an aliphatic conjugated polyene (2). As a crack resisting matrix is mentioned the copolymer of styrene, divinylbenzene and butadiene with e.g. dioctylphthalate as a plasticizer (176). Other examples are the copolymers of unsaturated aromatic compounds and unsaturated aliphatic compounds (77) and the reaction products of polyolefines and partially polymerized styrene (174). Primary groups can be introduced also with the help of Friedel-Crafts catalyst. Ts. Kuwata and co-workers treated a film of a copolymer of styrene and butadiene with an aluminium-ether complex and ethylenedichloride (79). Afterwards they allowed the film to react with trimethylamine. Another technique is the grafting of e.g. a polyethylene film with styrene (28). 

Also it is possible to swell e.g. a polyethylene film in a mixture of styrene, divinylbenzene and a catalyst and after that to polymerize in the film (50, 58). 

On stirring at room temperature ozonides of terminal alkenes (prepared in dichloromethane at — 70 °C) with a polymer-supported tertiary amine obtained from chloromethylated poly(styrene/divinylbenzene) and piperidine, followed by filtration and concentration under reduced pressure, the products (aldehydes or ketones) can be obtained easily in almost pure form in high yields <2003T493>. However, yields are low for cycloalkenes because apparently they form monomeric and polymeric ozonides. 

Synthetic styrene divinylbenzene and other polymers, particularly the trade-marked XAD resins developed by Rohm Haas, were used for SPE in the late 1960s and early 1970s. However, the particle size of the XAD resins is too large for efficient SPE applications, and therefore the resins require additional grinding and sizing. Also, intensive purification procedures are needed for XAD resins [73,75],... 

Polymer-based materials have been on the market for more than 30 years. Crosslinked styrene-divinylbenzene and methylmethacrylate copolymers are the most widely used. These materials show high pH stabihty and chemical inertness. Their rigidity and resistance to the swelhng in different mobile phases is dependent on the degree of crosslinkage. 

Figure 13-13. Comparison of choice of sample preparation on MRM signal intensity of an investigation compound. The injection volume was 40pL.The count per second (CPS) signifies the detector (an electron multiplier) response. Protein precipitation (PPT), hydrophilic-lipophilic balanced co-polymer-based SPE (Oasis HLB- copolymer of styrene, divinylbenzene and -vinylpirrolidone monomers the hydrophihc refers to the NVP monomer, and the lipophilic refers to the SDVB monomers), and strong anion exchange SPE (Max) (all in 96-well plate format) were used in control rat plasma (unpublished data).

Stannic chloride has been attached to monomers 21 containing ester (21a), carbazole (21b), pyrrolidone (21c), nitrile (21d) and pyridine (21d) moieties. The polymeric ligands were prepared by copolymerization of styrene, divinylbenzene and functional monomers such as methyl methacrylate, A -vinylcarbazole, Af-vinylpyrrolidone, acrylonitrile and 4-vinylpyridine [33], These polymers were treated with stannic chloride in chloroform to afford the corresponding polymer-supported stannic chloride complexes (Eq. 8). These polymeric complexes have been used as catalysts for such organic reactions including esterification, acetalization, and ketal formation. These complexes had good catalytic activity in the reactions and could be reused many times without loss of activity. Their stability was much better than that of plain polystyrene-stannic chloride complex catalyst. 

Catalyzed enantioselective Mukaiyama-aldol reactions have been developed extensively [101] and chiral polymer-supported Lewis acids are the catalysts of choice. Polymer-supported chiral A(-sulfonyloxazaborohdinones 86 and 87, prepared by copolymerization of styrene, divinylbenzene, and chiral monomers derived from L-valine and L-glutamic acid, respectively, have been used for aldol reactions [102]. The rates of reaction using the polymeric catalysts were slow and enantioselectivity was lower than was obtained by use of the low-molecular-weight counterpart (88). The best ee obtained by use of the polymeric catalyst was 90 % ee with 28 % isolated yield in the asymmetric aldol reaction of benzaldehyde with 89 (Eq. 27). 

Emulsion polymerization of styrene-divinylbenzene and styrene-acrylonitrile mixtures using the competitive growth technique (40)... 

Synthesis routes are reviewed for preparation of polymers from styrene, divinylbenzene (and possibly functionalized monomers) to give membranes, gel-form beads, and macroporous beads. Methods are summarized for functionalization of these polymers to give pendent groups such as -Br and -CH2CI, which can be converted into ligands such as -PPI12, -NR2>... 

Adsorption chromatography exploits differences in the relative affinity of solutes for a solid adsorbent used as the stationary phase. Common stationary phase materials for adsorption chromatography are porous silica gel, activated alumina, activated carbon, magnesium oxide, carbonates, and highly cross-linked polymers such as styrene-divinylbenzene and methac-rylates. The chemical natures of these adsorbent stationary phase materials make them well suited for separations of solute mixtures that differ in polarity and chemical functionality. For example, silica is an acidic adsorbent that retains basic compounds to a greater extent than nonbasic ones. In contrast, alumina... 

Depending on the ionic charge(s) of the solutes to be separated, anion or cation exchange stationary phases must be used. Common ion exchange support materials include silica, poly(styrene-divinylbenzene), and cellulose. Common anion exchange groups anchored to these supports include 1°, 2°, 3°, and 4"" amines. 

Only a few simple polymer-supported catalysts have found industrial use. All are strong acids, sulfonated poly(styrene-divinylbenzene), and are used in processes including phenol alkylation, the phenol-acetone condensation reaction to give bisphenol A, and the conversion of methanol and isobutylene into methyl-f-butyl ether, a high-octane gasoline component. 

A copolymerization of styrene, divinylbenzene, and maleic anhydride was carried out in the presence of silica. This was hydrolyzed in boiling water, then treated with chloroplatinic acid to add platinum on silica.64 Presumably, the anhydride reacted with the hydroxyl groups on the surface of the silica. Then the platinum (II) formed a salt with some of the carboxyl groups. 

The cross-linked polymer 27 (cross-linker not represented) containing the HOSu residue for anchored DCC-promoted active ester formation was also obtained by copolymerization of N-acetoxymaleimide with styrene and divinylbenzene, followed by hydrolysis [102]. In addition, supported HOSu-active esters have been prepared by a method consisting of the synthesis of N-hydroxymaleimide esters of N-protected amino acids and subsequent copolymerization of these esters with styrene, divinylbenzene and 4-chlorophenylmaleimide [103]. 

G.W. Bodamer and P.A. Cheltenham, Permselective films of anion-exchange resins, USP 2,681,319, 1954 Permselective films of cation-exchange resins, USP 2,681,320, 1954 B.L. Tye, Improvements to ion-exchange membranes, BP. 823,077, 1959 N. Tamura, Heterogeneous cation exchange membranes synthesized by the sulfonated emulsion copolymers of styrene/divinylbenzene and polypropyrene, Nihon Kagaku Zasshi, 1976, 1976, 654, etc. 

Native and microcrystalline cellulose precoated plates are used in the life sciences for the separation of polar compounds (e.g. carbohydrates, carboxylic acids, amino acids, nucleic acid derivatives, phosphates, etc) [85]. These layers are unsuitable for the separation of compounds of low water solubility unless first modified, for example, by acetylation. Several chemically bonded layers have been described for the separation of enantiomers (section 10.5.3). Polyamide and polymeric ion-exchange resins are available in a low performance grade only for the preparation of laboratory-made layers [82]. Polyamide layers are useful for the reversed-phase separation and qualitative analysis of phenols, amino acid derivatives, heterocyclic nitrogen compounds, and carboxylic and sulfonic acids. Ion-exchange layers prepared from poly(ethyleneimine), functionalized poly(styrene-divinylbenzene) and diethylaminoethyl cellulose resins and powders and are used primarily for the separation of inorganic ions and biopolymers. 

Chloromethylated resins were also synthesised by copolymerisation of styrene, divinylbenzene and chloromethylstyrene 7.83.84 (usually as a 3 2-mixture of meta and para isomers). Arshadi et al. noticed, however, that this approach can lead to substantial losses of chlorine content... 

Shea, K.J. Stoddard, G.J. Sasaki, D.Y. Flourescence probes for the evaluation of diffusion of ionic reagents through network polymers. Chemical quenching of the flourescence emission of the dansyl probe in macroporous styrene-divinylbenzene and styrene-diisopropylbenzene copolymers. Macromolecules 1989, 22, 4303-4308. 

Definition Diethanolamine salt of a polymer of styrene, divinylbenzene, and two or more monomers of acrylic acid, methacrylic acid or their simple esters... 

The use of crosslinked polymers of high specific surface area as stationary phase in the separation of some mixtures has extended the application of gas chromatography to the study of specific surface area of polymers [il4—116]. Thus, polymeric porous powders were studied, such as polyethylene [117], crosslinked copolymers of styrene, divinylbenzene, and ethyl vinyl benzene which may also contain other polar co-monomers whose commercial names are Porapak and Chromosorb [118, 119], carbon black, zeolites treated with poly(ethylene oxide) [120], and silicagel and rutile treated similarly [121, 122]. Although the mechanism of partition on these porous polymers is disputed it seems that adsorption has an important share [116]. 

Similar data are available with styrene/divinylbenzene and methyl-methacrylate/ethylene glycol dimethacrylate copolymers (the second molecule providing cross-links). 

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