• Journal of Pharmaceutical Investigation
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• v.18 no.2
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• pp.69-81
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• 1988

We studied on the synthesis of chloromethylated polystyrene as a precursor of optically active polymers for direct resolution of optical isomers. Changing the degree of crosslinking and the kind of crosslinking agents, several polystyrene resin matrices were synthesized. The matrices were chloromethylated with methylal and chlorosulfonic acid as chloromethylating agents. The effects of solvents of various dielectric constants on the chloromethylation were quantitavely examined. We also synthesized chloromethylated polystyrene of macroreticular type that retained large surface area and good physical stability. The differences between the macroreticular type and macroporous type were investigated.

• Analytical Science and Technology
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• v.12 no.6
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• pp.465-471
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• 1999

Chloromethylated polystyrene resins supported diethylenetriamine of linear and claw types have been prepared by the reaction of diethylenetriamine with chloromethylated polystyrene. The kinetics of adsorption of transition metal ions on polystyrene resins were measured by the limited-bath technique. This paper reports the results of the diffusion coefficients, entropies of activation, and free energies of activation. The ratedetermining step of the adsorption of transition metals on the resins is a process of diffusion through the particles.

• Journal of the Korean Chemical Society
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• v.35 no.1
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• pp.16-23
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• 1991

Resins of polystyrene supported triethylenetetramine of linear and claw types have been prepared by the reaction of triethylenetetramine with chloromethylated polystyrene. The resin supported triethylenetetramines were principally characterized by infrared spectra. Kinetics of adsorption of transition metals on the resin have been investigated. This paper reports the results of the diffusion coefficients and entropies of activation. The rate determining step is a process of diffussion through the particle.

• Journal of Environmental Science International
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• v.9 no.4
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• pp.319-323
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• 2000

Nitrate-selective ion exchange resin which have bulky tertiary amine as functional group have been synthesized by the reaction of chloromethylated polystyrene-divinylbenzene copolymer and the corresponding tertiary amine [$NR_3=NE_{t3} 1, N{(C_2 H_4 H_3)}_32]$in ethanol, while commercial resin has $NMe_3$ as functional group. The fundamental properties such as bulk density, water content, appearance index, exchange capacity, effective size, uniformity coefficient of synthesized anion exchange resin (1) have been measured. The ion exchange resin (1) and (2) exhibited the better selectivity for nitrate than sulfate in both batch and continuous column experiments.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.355-358
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• 2005

Nitrate-selective ion exchange resins involving bulky trialkyl amino as functional group were synthesized by the reaction of chloromethylated polystyrene-divinylbenzene copolymer and the corresponding tripropylamine in ethanol. Fundmental properties such as bulk density, water content, effeative diameter, uniformity coefficient, appearance index, exchange capacity and particle size distribution were fully measured. The synthesized resins appeared to be good for nitrate selection.

• Analytical Science and Technology
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• v.6 no.5
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• pp.443-451
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• 1993

Pentaethylenehexaamine(penten) was reacted with a chloromethylated polystyrene resin on the purpose of the synthesis of polyamine chelating resin, $(P)_c$-penten. The stepwise dissociation constants of the synthesized polyamine chelating resin and the stability constants with metal ions were determined by Bjerrum's method. These stability constants were compared with those of the free penten. The adsorptivities and eluting tendencies of several metal ions on the chelating resin were studied.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3765-3770
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• 2010

Selective oxidation of olefins has been carried out in water medium with tert-butylhydroperoxide (TBHP, 70% aqueous) as an oxidant using polymer-anchored Ni(II) complex as a catalyst. Several parameters were varied to optimize the reaction conditions. Under the optimized reaction conditions olefins gave selectively allylic oxidation products. The present polymer anchored Ni(II) complex can be recycled five times without any appreciable loss in catalytic activity.

• Journal of Pharmaceutical Investigation
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• v.19 no.3
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• pp.117-121
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• 1989

A metal complex, copper (II) L-proline was chemically bound to ethylene glycol dimethacrylate and divinylbenzene crosslinked chloromethylated polystyrene and they were used as chiral chelate resin matrix for column chromatography to resolve enantiomers of DL-amino acids. The L-enantiomers eluted first and the degree of resolution on the polymer crosslinked with ethylene glycol dimethacrylate was superior to the polymer crosslinked with divinylbenzene.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.593-602
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• 1988

Polymer-supported crown ethers (Ps-CE) which can be used for phase-transfer catalyst (PTC) were synthesized for the purpose of allowing reusable function to ordinary crown ethers, and the kinetics of the liquid-solid-liquid triphase-catalyzed nucleophilic displacement reaction of iodide (aqueous phase) on 1-bromooctane (organic phase) using synthesized Ps-CE (solid) were studied. Ps-CE were obtained by grafting of hydroxymethyl crown ethers to 1~2% cross-linked chloromethylated polystyrene. All reactions followed a pseudo-first order dependency on the 1-bromooctane concentration and the observed rate constants $(k_{obsd})$ were linearly related to the molar equivalents of Ps-CE, and were subjected to the influence of cross-linking density of polymer backbone, solvent and the reaction temperature. The catalytic activity of Ps-CE was also compared with that of structurally similar soluble crown ethers, and used Ps-CE were easily recovered after the reaction by simple filtration and could be reused without loss of catalytic activity in the same anionic displacement reaction. Enthalpies and entropies of activation associated with the displacement were 10~20kcal $mol^{-1}, 20~55eu. respectively, and the free energy of activation was ~30kcal mol^{-1}$.

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.214-219
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• 1998

Dynorphin B analogues, $[Arg^{11}, D-Ala^{12}]$dynorphin B, $[D-Ala^2, Ala^6, Arg^{11}, D-Ala^{12}]$dynorphin B, and dynorphin B (1-11) were synthesized by solid-phase method. A chloromethylated polystyrene resin cross-linked with 2% divinylbenzene was substituted with Thr in ethanol to contain 1.20 mmol Thr/g of resin. All amino groups of amino acids were protected with t-Boc group and 2,6-dichlorobenzyl and nitro groups were used to protect the side chains of Tyr and Arg, respectively. Stepwise synthetic method was applied for synthesis of the products. Dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBT) were used as the coupling reagents. The crude peptides were purified by gel filteration on Sephadex LH-20 column $(2 \times 50 cm)$ using MeOH/MeCN (3/1) and then characterized with HPLC, amino acid analyzer.