• Journal of Electrochemical Science and Technology
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• v.3 no.2
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• pp.85-89
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• 2012

This study demonstrates the direct anodic electrodeposition of polypyrrole (PPy), poly(3,4-ethyl-enedioxythiophene) (PEDOT), and polythiophene (PTh) on Cu electrodes by employing a corrosion inhibitor, succinonitrile (SN). SN was found to suppress anodic Cu dissolution beyond the oxidation potential of the polymer monomers. It is also revealed that the Cu surface passivated by SN is still adequately conductive to allow the redox reaction of 1,4-difluoro-2,5-dimethoxybenzene (FMB) and the oxidation of the polymer monomers. Through both cyclic voltammetry and galvanostatic techniques, PPy, PEDOT, and PTh films were successfully synthesized on Cu electrodes in the presence of SN, and the redox behaviors of the films were evaluated.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1201-1210
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• 2002

A new series of hyperbranched aromatic polyesters containing azoxybenzene mesogens and polymethylene spacers were prepared by polymerizing AB2 type monomers that have the isophthaloyl dicarboxylic acid terminal at one end and the p-oxyp henol terminal at the other end. The monomers contain a built-in azoxybenzene mesogen that is linked to the terminal groups through polymethylene spacers. The polyesters prepared were characterized by solution viscosity, differential scanning calorimetry, X-ray diffractometry and polarizing microscopy. All of the polyesters were found to be thermotropic (nematic). Their glass-transition temperatures and mesophase temperature ranges were very sensitive to the length of the two spacers existing in the repeating unit. The degree of branching of one of the polyesters was determined by the NMR spectroscopy and found to be 0.56.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.94-97
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• 1998

We have been studying :he synthesis of thermotropic polyurethanes, based on structural modifications by means of (i) the introduction of bulky substituent group in the aromatic ring to decrease the degree of lateral packing, (ii) the copolymerization of two kinds of monomers having different alkylene lengths to lower the regularity of the polymer structure, and (iii) the use of nonlinear monomers to lower the persistence length of the polymer chain in the liquid crystalline phase and to decrease the lateral interactions in the solid state. (omitted)

• Macromolecular Research
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• v.13 no.3
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• pp.253-256
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• 2005

We prepared amino acid-derived diacetylene monomers using solid-phase organic synthesis. The solid-phase synthetic method allowed for the rapid and efficient preparation of functional diacetylenes. Amino acids having hydrophobic sidechains such as alanine, leucine, and phenylalanine, as well as hydrophilic sidechains such as aspartic acid and lysine, were successfully coupled to the diacetylene lipid. The diacetylene monomers prepared in this way were subjected to routine procedures for the generation of polydiacetylene vesicles. Depending on the nature of the side-chains, pink to blue colored polydiacetylenes were generated.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.8-14
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• 2008

Flame-retardant cotton fabrics were prepared by UV curing of photocurable aqueous formulations of phosphorous-containing methacrylate monomers and 2-hydroxy-2-methyl-1-phenyl-1-propanone as flame retardants and a photoinitiator respectively, which is an environmentally friendly and energy-saving process. The characterization of the UV-coated cotton fabric was made by ATR, TGA and limited oxygen index measurement. UV cured coating onto cotton fabrics reduced the first thermal decomposition temperature and mass loss as well as increase in the amount of char residue compared with the untreated cotton fabric presumably due to modified thermal decomposition process. The LOI values up to 28.5 and 27.2 were obtained by the UV curing of MMEP and TMEP respectively. The treatment was durable to five laundering cycles, which was more prominent in the case of trifunctional TMEP treatment.

• Rapid Communication in Photoscience
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• v.1 no.2
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• pp.27-29
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• 2012

Noble diamine monomers containing thiophene moiety were prepared, such as 2,5'''-diamino-2, 2':5', 2'':5'', 2'''-quaterthiophene (4TDA) and 2, 5'''''-diamino-3'', 4'''-dihexyl-2,2':5', 2'':5'', 2''':5''', 2'''':5'''', 2'''''-sexithiophene (6TDA). Then, these monomers were utilized to prepare polyimides with 3,6-diphenylpromellitic dianhydride (DPPMDA), 3,6-di(4'-trifluoro-methylphenyl) pyromellitic dianhydride (6FPMDA) or 3,6-di(3',5'-bis (trifluoromethyl)phenyl) pyromellitic dianhydride (12FPMDA) via a conventional two-step process. The polyimides were characterized by FT-IR, TGA and DSC, and then subjected CV, UV-vis and PL measurements. The polyimides containing thiophene moiety exhibited high glass transition temperatures ($280{\sim}310^{\circ}C$) and excellent thermal stability (> $420^{\circ}C$) in air as well as green emission (535~586 nm).

• Membrane Journal
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• v.4 no.1
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• pp.46-56
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• 1994

The performane of prepared Thin-Film Composite membrane depends on supporting membrane, concentration of monomers, dipping time of supporting membrane into monomer solution, reachon time between monomers, curing temperature and time and posttreatment. This study was conducted for searching the optimal condition for making the composite membrane. For this purpose, supporting membrane and composite membrane was made under various condition and at each step were tested.

• Elastomers and Composites
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• v.51 no.2
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• pp.154-160
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• 2016

The four different vinyl monomers in the reaction of isocyanate-terminated polyurethane prepolymer were used for the preparation of macromonomers and successfully employed in the dispersion polymerization of styrene. The chemical structures of vinyl monomer in macromonomers influenced on the polystyrene particle characteristics, such as the conversion, weight average molecular weights ($M_w$), polydispersity index (PDI), weight average diameter ($D_w$), and uniformity. The conversion of polystyrene increased with amounts of methyl group in vinyl monomer. Also the uniformity of polystyrene particles increased with amounts of methyl group in vinyl monomer.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.261-269
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• 2012

The cyclic dimers of enkephalin were isolated as minor components during the solution synthesis of the corresponding cyclic monomers. The ratio of cyclic dimer to monomer was approximately 1:4 from the percent of yields. In the receptor binding assay of two cyclic dimmers, ($Tyr_2-C[D-Glu-Phe-gPhe]_2$ 6, $Tyr_2-C[D-Asp-Phe-gPhe-rLeu]_2$ 8), both analogs exhibited the high preference for ${\delta}$ receptor compared to monocyclic counterparts. In the nociceptive activity, both showed about 5 times less potent than the cyclic monomers. The repeated synthesis of 14-membered cyclic analog, Tyr-C[D-Glu-Phe-gPhe-D-rLeu] 14, which was known as having three distinct cis-trans isomers, gave rise to apparently different conformational analog arousing only trans isomer. In the receptor binding assay, it showed tremendously high selectivity toward ${\mu}$ receptor $({\delta}/{\mu}=160)$.

• Macromolecular Research
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• v.15 no.2
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• pp.134-141
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• 2007

The direct chromatographic separation of enantiomers by chiral stationary phases (CSPs) has been extensively developed over the past two decades, and has now become the most popular method for the analytical and preparative separations of enantiomers. Polysaccharide derivatives coated onto silica gel, as CSPs, playa significantly important role in the enantioseparations of a wide range of chiral compounds using high-performance liquid chromatography (HPLC). Unfortunately, the strict solvent limitation of the mobile phases is the main defect in the method developments of these types of coated CSPs. Therefore, the immobilization of polysaccharide derivatives onto silica gel, via chemical bonding, to obtain a new generation of CSPs compatible with the universal solvents used in HPLC is increasingly important. In this article, our recent studies on the immobilization of polysaccharide derivatives onto the silica gel, as CSPs, through radical copolymerization with various vinyl monomers are reported. Polysaccharide derivatives, with low vinyl content, can be efficiently fixed onto silica gel with high chiral recognition.