• Journal of the Korean Chemical Society
• /
• v.27 no.3
• /
• pp.189-193
• /
• 1983

The lithium isotopes separation experiments were carried out in hydrochloric acid with cation exchanger systerns. In these experiments were employed porous sulfonated styrene-divinylbenzene copolymer and Dowex 50w-x8 as cation exchanger. The contents of lithium of the fraction were determined with atomic absorption spectrophotometer. The relative mass of lithium isotopes of the fractions was analyzed on a mass spectrometer. The isotope separation factors of lithium were calculated from the isotope compositions of these eluted fractions. Separation factor for the system in hydrochloric acid and porous sulfonated styrene-divinylbenzene copolymer was found to be 1.0020, and for the case of system in hydrochloric acid and Dowex 50w-x8 was 1.0011${\om}$0.0002. From these results, we found that the separation factor for porous sulfonated styrene-divinylbenzene copolymer ionexchanger is larger than value of Dowex 50w-x8 ionexchanger.

• Journal of the Korean Chemical Society
• /
• v.29 no.3
• /
• pp.283-286
• /
• 1985

The non porous and porous 4-vinylpyridine-divinylbenzene ion exchange resins were synthesized by the suspension polymerization method. The functional groups of these resins were identified by means of infrared adsorption spectroscopy. The pore volume and pore spectra of these synthesized resins were determined with a mercury porosimeter. The influence of diluent and percentage of divinylbenzene on the pore size and volume of the porous 4-vinylpyridine-divinylbenzene copolymer, P-4VPDVB, 50-100 mesh was discussed. The ion exchange capacity of non-porous and porous 4-vinylpyridine divinylbenzene resins was 5.0meq/g, respectively.

• Journal of the Korean Chemical Society
• /
• v.16 no.1
• /
• pp.46-49
• /
• 1972

Using an assumption of isoviscosity at the gel-point in the polymerization of divinylbenzene, the relations between viscosity equation, viscosity-molecular weight, and the chain transfer equation have been studied. A new equation for the calculation of chain transfer constant, $C_{tr}$, by measuring the gel time in place of the degree of polymerization has been suggested.

• Journal of the Korean Chemical Society
• /
• v.25 no.3
• /
• pp.160-165
• /
• 1981

Radical copolymerization of the complexed 2-vinylpyridine with vinyl acetate and divinylbenzene initiated by azobisisobutyronitrile was carried out in N, N-dimethylformamide in presence of barium chloride at $98{\circ}C$. In the preparation of 2-vinylpyridine-vinylacetate-divinylbenzene terpolymer, the optimum reaction conditions were studied by means of various temperatures and times. 2-vinylpyridine-vinylalcohol-divinybenzene resin was prepared by transesterificating 2-vinylpyridine-vinylacetate-divinylbenzene terpolymer with a 1% methanolic sodium hydroxide solution. 2-Vinylpyridine-vinylphosphate-divinyldenzene was prepared by phosphorylating 2-vinylpyridine-vinylalcohol-divinylbenzene resin with phosphoric acid and urea. The compositions of each synthetic resin were identified by means of infrared absorption spectroscopy. The ion exchange capacities of each 2-vinylpyridine-vinylalcohol-divinylbenzene and 2-vinylpyridine-vinylphosphate-divinylbenzene terpolymer was 3.69 meq/g and 5.38 meq/g.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.8
• /
• pp.1627-1629
• /
• 2008

• Korean Journal of Agricultural Science
• /
• v.9 no.2
• /
• pp.584-590
• /
• 1982

Copolymerization of the 4-vinylpyridine with vinylacetate and divinylbenzene initiated by azobis-isobutyronitrile was carried out in DMF in presence $BaCl_2$ at $98^{\circ}C$. Ion exchange res in, poly 4-vinylpyridine-vinylsulfonic acid-divinylbenzene was prepared by sulfonation of 4-vinylpyridine-vinylacetatp-divinylbenzene with concentrated sulfuric acid. The compositions of each synthetic resin were identified by means of ir adsorption spectroscopy. Anion and cation capacities of 4-vinylpyridine-vinylsulfonic acid-divinylbenzene ion exchanger were 2.5meq/g and 4.8meq/g, respectively. Adsorption of Cd(II) and Cu(II) ions have showed larger quantity in alkalie media. A study also was made of the influence of alcohol on the distribution coefficient of Cd(II) and Cu(II) ions between the synthetic ion exchanger, and solution containing hydrochloric acid, various alcohols and water. The distribution coefficients of metal ions decrease generally as the number of branches of carbon in the molecule of butyl alcohol increase. (t-BuOH

• Journal of the Korean Chemical Society
• /
• v.29 no.3
• /
• pp.233-238
• /
• 1985

The non-porous and porous polystyrene divinylbenzene copolymers were prepared by the suspension polymerization method. The non-porous aminated polystyrene divinylbenzene, N-APSTDVB and the porous aminated polystyrene divinylbenzene, P-APSTDVB of 50∼100mesh size weakly basic anion exchanger were synthesized by chloromethylation followed by amination with methylamine. The functional groups of these synthesized anion exchangers were confirmed by their infrared spectra. The maximum capacity of these exchangers was 4.86meq/g. Pore volume and pore spectra were determined with a mercury porosimeter. The pore volume of P-PSTDVB increased with increasing X$_{diluent}$ at 30% of divinylbenzene. However, the pore volume of P-PSTDVB increased with increasing volume percent of divinylbenzene at constant mole fraction of diluent, X$_{diluent}$ of 0.5. The pore volume of synthesized copolymer and anion exchanger at 8% divinylbenzene and 0.5X$_{heptane}$ decreased as follows; P-PSTDVB 〉P-APSTDVB 〉N-PSTDVB. This result was attributed to the possibility that the pore volume were reduced by amination reactions. The distribution coefficients of boric acid on the N-APSTDVB anion exchanger in various concentrations of alcohol water solutions showed that as alcohol concentration increased, the distribution coefficients values decreased due to the reduced concentration of H$_2$BO$_3^-$.

• Elastomers and Composites
• /
• v.46 no.4
• /
• pp.304-310
• /
• 2011

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using briged rac-$Et[Ind]_2ZrCl_2$ or unbriged $Cp_2ZrCl_2$ metallocene catalysts. Bridged rac-$Et[Ind]_2ZrCl_2$ catalyst showed relatively good results compared with unbridged one. When cocatalyst/catalyst molar ratio was 3000, catalytic activity indicated more than 8000(kg of polymer/$mol{\cdot}h$) which was very remarkable value. As a polymerization time increased, the weight-average molecular weight of the terpolymer gradually increased to some degree. In the case of a polymerization time of 50 minutes, the state of the terpolymer became amorphous. The range of the weight-average molecular weight and the densities of the terpolymer was 110,000~200,000 and $0.85{\sim}0.89g/cm^3$, respectively. The thermal properties and the structure of the terpolymer were also identified.

• Applied Chemistry for Engineering
• /
• v.20 no.3
• /
• pp.273-278
• /
• 2009

A series of poly[2-(2,6-dimethylpyran-4-ylidene)malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PM-PPV), poly[2-{2,6-Bis-[2-(5-bromothiophen-2-yl)-vinyl]-pyran-4-ylidene}-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMT-PPV) and poly[2-[2,6-Bis-(2-{4-[(4-bromophenyl)-phenylamino]-phenyl}-vinyl)-pyran-4-ylidene]-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMTPA-PPV) were synthesized by the Heck coupling reaction. The band gap of PM-PPV, PMT-PPV and PMTPA-PPV were 2.18 eV, 1.90 eV and 2.07 eV, respectively. The LUMO energy levels of PM-PPV, PMT-PPV and PMTPA-PPV were 3.65 eV, 3.54 eV and 3.62 eV, respectively and the HOMO energy levels of those were 5.83 eV, 5.61 eV and 5.52 eV, respectively. The photovoltaic devices based on the polymers was fabricated. The efficiency of the solar cells based on PM-PPV, PMT-PPV and PMTPA-PPV were 0.028%, 0.031% and 0.11%, respectively and the open circuit voltage (Voc) was 0.59 V~0.69 V under AM 1.5 G and 1 sun condition ($100mA/cm^2$).

• Polymer(Korea)
• /
• v.39 no.1
• /
• pp.157-164
• /
• 2015

In this study, we synthesized poly(vinylimidazole-co-trifluoroethylmethacrylate-co-divinylbenzene) (PVTD) copolymer and introduced functional group through quaternization reaction for removing nitrate from drinking water. Also, optimizing conditions (reaction time, reaction temperature and functionalized agents concentration) for introducing the functional group were confirmed. The basic properties such as water uptake, swelling ratio, electrical resistance, ion exchange capacity and anion permselectivity for removing nitrate from drinking water were measured. The optimal values of water uptake, electrical resistance and ion exchange capacity of synthesized anion exchange membrane were 51.2%, $5.4{\Omega}{\cdot}cm^2$, and 1.04 meq/g, respectively.