• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.406-414
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• 2010

A novel polyacrylamide grafted hydrous ferric oxide adsorbent composite has been synthesized by using glow discharge electrolysis plasma. To optimize the synthesis conditions, the following parameters were examined in detail: applied power, discharge time, post polymerization temperature, post polymerization time, amount of crosslinking agent and hydrous ferric oxide gel added and so on. The adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The removal percentage of the adsorbent in Pb(II) solution was examined and the data obtained showed that the adsorbent composite has a high capacity for lead ion. For the use in wastewater treatment, the thermodynamic and kinetic of Pb(II)-capture were also studied. Results indicated that the adsorption reaction was a spontaneous and an endothermic process, and it seems to be obeyed a pseudo-secondorder rate model. Moreover, the adsorption isotherm of Pb(II)-capture is following the Langmuir and Freundlich isotherm models.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.456-461
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• 2013

Using the different adsorption properties of ssDNA and dsDNA to GO, this study used a real time and efficient fluorescence assay to detect the enzymatic activity of the Klenow fragment with the adsorbed DNA to GO. Results showed that adsorption of fluorescein-tagged ssDNA to GO resulted in fluorescence quenching and DNA was released from GO by adding complementary DNA. In addition, fluorescence restoration was increased through a polymerization reaction by the Klenow fragment in the presence of a fluorescein-attached template, GO, and primer. Gel electrophoresis was conducted to confirm the hybridization and DNA polymerization reactions on GO.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.156-157
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• 2006

Quasi-living polymerization conditions for the copolymerization of ethylene and functionalized norbornenes can be achieved by using an initiator system comprising $[N-(2,6-diisopropylphenyl)-2-(2,6-diisopropylphenylimino)-propanamidato-{\kappa}^2N,O]Ni({\Box}^1-CH_2Ph)(PMe_3)\;and\;Ni(COD)_2$. It is possible with this polymerization system to obtain block-copolymer and tapered structures. The latter form microdomains similar to those of standard block co-polymers. The mechanism of the reaction will also be discussed.

• Carbon letters
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• v.14 no.4
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• pp.251-254
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• 2013

In this study, poly(amic acid) was prepared via a polycondensation reaction of 3,3'-dihydroxybenzidine and pyromellitic dianhydride in an N-methyl-2-pyrrolidone solution; reduced graphene oxide/polybenzoxazole (r-GO/PBO) composite films, which significantly increased the electrical conductivity, were successfully fabricated. GO was prepared from graphite using Brodie's method. The GO was used as nanofillers for the preparation of r-GO/PBO composites through an in situ polymerization. The addition of 50 wt% GO led to a significant increase in the electrical conductivity of the composite films by more than sixteen orders of magnitude compared with that of pure PBO films as a result of the electrical percolation networks in the r-GO during the thermal treatment at various temperatures within the films.

• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.207-212
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• 1973

The mechanical degradation of poly (-vinylacetate) in several mixed solvents (dioxane-n-butanol, dioxane-sec-butanol, dioxane-ethyleneglycol, dioxane-kerosene.) was studied using the capillary flow method. The velocity constant of scission reaction (k) and the limited degree of polymerization (g) were compared at the same value of [${\eta}$], which is considered as the parameter of molecular dimension of polymers in solution. As result, (k) did not change much, even if the species and the volume fraction of poor (non-) solvents changed, while the value of (g) changed according to the species of poor solvents and the value of [${\eta}$]. From the facts described above, It follows that the limited degree of polymerization (g) were affected by the composition and distribution of mixed solvent molecules around the polymer chain, and the value of $\alpha$ (at [${\eta}$] = $KM^a$) in the polymer solution.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.75-79
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• 2009

The ratio of aniline dimer (p-aminodiphenylamine), which is a nucleation site of chain growth in a chemical polymerization of aniline monomer, to aniline monomer was controlled to synthesize polyaniline with the molecular weight ($M_w$) between 10000 and 20000 g/mol. The result of OCP measurement showed that the reaction rate of polymerization was increased as the mole ratio of dimer was increased. The increase in the molar ratio of dimer resulted in the shift of absorption wavelength of polyaniline to the short wavelength region on measurement of UV/Vis and the decrease of molecular weight on the measurement of GPC.

• Journal of the Korean Applied Science and Technology
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• v.25 no.4
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• pp.485-494
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• 2008

The acrylic coating emulsions were prepared by the emulsion polymerization to protect the surface of steel plate from the corrosion chemicals like acid, base and salt water. MMA(methyl methacrylate), styrene, BA(butyl acrylate), and 2-HEMA(2-hydroxyethyl methacrylate) were used as monomer. KPS(potassium persulfate) and SBS(sodium bisulfite) as redox initiator and SDBS(sodium dodecylbenzene sulfonate) as emulsifier were used on the emulsion polymerization reaction. The most stable in-situ coating was obtained when 10% of MMA was added. Both particle size and quantity in emulsion were decreased as increasing the mount of SDBS. the most stable prepared coating emulsion with polyisocyanate crosslinker showed very high anticorrosion properties on the coated steel layer to salt water, whereas no significant improvement of anticorrosion property to acdic and basic condition it showed.

• Macromolecular Research
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• v.8 no.3
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• pp.131-136
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• 2000

The synthesis of poly(2-ethynylpyridine) having glycidyl functionality was performed by the direct polymerization of 2-ethynylpyridine and epibromohydrin under mild reaction conditions without any initiator and catalysts. The polymerization proceeded well to give the resulting poly(2-ethynylpyridinium bromide) with a glycidyl functionality having relativity high molecular weight in high yields. The polymer structure was characterized by various instrumental methods to have the conjugated polymer backbone structure having glycidyl functionality. This ionic polymer was completely soluble in water, methanol, DMF, DMSO, and N,N-dimethylacetamide, but insoluble in THF, toluene, acetone, nitrobenzene, and n-hexane. This polymer system exhibited the UV-visible absorption around 300 and 520 nm and red photoluminescence spectrum around 725 nm.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.561-564
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• 2006

$SnO_{2}$-doped anatase type $TiO_{2}$ powder was prepared by the polymerization complex route from tin(IV) bis (acetylacetonate) dichloride, titanium diisopropoxide bis (acetylacetonate) and polyethylene glycol (PEG) as a complexing agent. The structural changes of reaction mixture were monitored by fourier transform infarared (FT-IR) spectroscopy. The microstructure and morphology of gel powder were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffractometry (XRD). The photocatalytic activity of these powders with the anatase structure was investigated by using indigo carmine solution.