• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.539-545
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• 2012

3-(2-benzotriazolovinyl)thiophene (BVT) was synthesized by the connection of the thiophene with the electron-withdrawing group, benzotriazole, through the vinylene. Its structure was confirmed by FT-IR, $^1H$-NMR, $^{13}C$-NMR and 2D hetero-cosy spectroscopy. Both BVT and 3-octylthiophene (OT) were copolymerized and showed an average molecular weight of 12000 (PDI 2.67) and 15000 (PDI 2.55), respectively. The copolymers were dissolved in the organic solvent such as chloroform, THF, TCE, etc. The mole ratios of BVT and OT in the synthesized copolymers were confirmed as 1 : 1.8 and 1 : 2.8 from $^1H$-NMR spectra. The UV-vis maximum absorption of copolymers appeared at the wavelength of 470 nm and 465 nm and the photoluminescence at ${\lambda}_{max}$ = 662 nm and 641 nm correspond to red-orange light. The band gaps of copolymers at 1.96 eV and 2.02 eV were found to be higher than those of poly(3-octylthiophene). The HOMO energy levels of the copolymers decreased overall in comparison with those of poly(3-octylthiophene), but the overall LUMO energy level increased.

• Polymer(Korea)
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• v.30 no.5
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• pp.367-372
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• 2006

Electrochromic materials based on conducting polymers with pendant chromophores as well as their electrochromic properties are described. The conducting polymers described aye polypyrrole, polythiophene, poly(3,4-ethylenedioxythiophene), poly (cyclopentadithiophene), and poly (1,4-bis [2- (3,4-ethylenedioxy) thienyl] benzene). The chromophores described are viologen and perylenetetra-carboxylic diimide. When the wavelength ranges of absorption of the conducting polymer and the chromophore aye not overlapping, multiple electrochromism was achieved. When the wavelength ranges are largely overlapping, higher contrast was achieved. An easy method for prediction of the film thickness for maximum contrast of a given electrochromic material is also described.

• Macromolecular Research
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• v.17 no.1
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• pp.31-36
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• 2009

Highly transparent, thin polythiophene (PT) films were successfully synthesized by the plasma polymerization of thiophene. These films were doped with $O_2$ plasma by in-situ doping technique. The plasma polymerized PT films were deposited at about 50 to 340 nm/min, depending on the temperature and plasma power. A resultant transparency as high as 85% was achieved. The plasma polymerized PT films exhibited the characteristics of an insulator or semiconductor ($10^{10{\sim}12}{\Omega}/{\Box}$, $10^{-7}S/cm$). The conductivity was immediately increased up to $10{\Omega}/{\Box}$ and $10^{-2}S/cm$, when doped with $O_2$ plasma. The plasma-doped PT films exhibited an increased surface roughness resulting in a decreased contact angle. However, the thickness of the PT layer was partially decomposed and/or etched with increasing voltage above 40 W.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.27-31
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• 2003

A Polythiophene-quinoline/glassy carbon (PTQ/GC) modified electrode was developed for the determination of trace mercury in industrial waste water, natural water, soil, and other media. The electrode was prepared by the cyclic voltammetric polymerization of thiophene and quinoline on glassy carbon (GC) electrode by the potential application from -0.6 V to +2.0 V (50 mV/sec) in a solution of 0.1 M thiophene, quinoline and tetrabutyl ammonium perchlorate (TBAP) in acetonitrile. Optimum thickness of the polymer membrane on the GC electrode was obtained with 20 repeated potential cyclings. The redox behavior of Cu(Ⅱ) and Hg(Ⅱ) were almost identical on this electrode. The addition of 4-(2-pyridylazo)resorcinol (PAR) to the solution containing Cu(Ⅱ) and Hg(Ⅱ) allowed the separation of the components due to the formation of the Cu(Ⅱ)-PAR complex reduced at -0.8V, which was different from the Hg(Ⅱ) reduced at -0.5 V on a saturated calomel electrode (SCE). The calibration graph of Hg(Ⅱ) shows good linear relationship with the correlation factor of 0.9995 and the concentration gradient of 0.33 ㎂/㎠/ppb down to 0.4 ppb Hg. The method developed was successfully applied to the determination of mercury in samples such as river, waste water, and sea water.

• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.467-473
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• 1996

Although a polypyrrole shows better electrical conductivity, 100∼400 ${\Omega}^{-1}cm^{-1}$, than other organic conducting polymers, its electrical conductivity will be worsen in the presence of the oxygen due to its easy oxidation. On the other hand, polythiophene shows better stability in the air while its electrcal conductivity is poor compared to the polypyrrole. We succeed to develope the mixed polymer electrode that is stable in the air and shows a good redox characteristics. The mixed polymer electrode has been prepared by the electrical polymerization of polypyrrole on the Pt electrode as 1.70 C$cm^{-2}$ and then coating with polythiophene as 0.34 C$cm^{-2}$. The polymerization rate of polythiophene was $3.89{\times}10^{-8}$ at the bare Pt electrode and $6.07{\times}10^{-8}cms^{-1}$ at the mixed polymer electrode. And the standard rate constants of each electrode were $5.16{\times}10^{-6}\;and\;3.94{\times}10^{-4} cms^{-1}$ respectively. Also, the electrocatalytic rate of the polypyrrole polymer electrode was $3.45{\times}10^{-3}cm^3mol^{-1}s^{-1}.$ We found the immobilized layer at the modified electrode acted as an electrocatalyst. Finally, this polymerization process at the Pt electrode was the electron transfer controlled, but that the mixed polymer electrode was the diffusion and charge transfer controlled.

• Electrical & Electronic Materials
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• v.7 no.6
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• pp.520-526
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• 1994

A rectifying heterojunction consisting of polyparaphenylene(PPP) and polypyrrole(PPY) films was prepared by the electrochemical method. The photoresponse in the heterojunction of PPY and PPP is similar to the absorption spectrum of undoped PPP. This fact suggests that photoresponse depends strongly upon polyparaphenylene of semiconductor. The fill-factor was calculated from the photo current-voltage curve to be 0.19, which is relatively small compared to polyacetylene-polythiophene heterojunctions.

• Macromolecular Research
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• v.14 no.2
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• pp.173-178
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• 2006

Poly(3-(2-hydroxyethyl)thiophene) (P3HET) was synthesized using oxidative coupling polymerization that involved the protecting and deprotecting of hydroxyl groups but not the chlorine substitution or oxidative decomposition of the hydroxyl groups. The resulting P3HET exhibited good solubility in aprotic solvents, in contrast to the insoluble polymer product synthesized directly from the monomer, 3-(2-hydroxyethyl)thiophene (3HET). P3HET had low conductivity due to the strong hydrogen bonding of its hydroxyl groups. The ester-functionalized poly(3-(2-acetoxyethyl)thiophene) and poly(3-(4-pentylbenzoateethyl)thiophene) were also prepared with reasonably high molecular weights in order to examine how this functionalization modified the physical and chemical properties of P3HET. These polymers exhibited better solubility in common solvents and higher conductivity than P3HET. All these polymers exhibited bathochromic shifts of their film state absorption maxima with respect to those found in the UV-visible spectra of their solution phases. The extent of the bathochromic shift was found to vary with the lengths of the side chains of the ester-functionalized polymers.

• Polymer(Korea)
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• v.26 no.1
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• pp.28-36
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• 2002

In this study, we synthesized novel thiophene derivatives by the protection of the carboxyl group of 3-thiophene acetic acid with differently substituted benzyl groups. While 3-thiophene acetic acid is not electro-polymerizable, the modified monomers can be easily electro-oxidized to form stable electroactive polymers. The protecting groups can be easily removed in the solid state and the desired reactive carboxyl group can be introduced on the polymer surface. SEM observations show that obtained polymer films show a very good film surface and homogeneous morphology on the Pt electrode. After introduction of macromonomer, FT-IR spectrum shows new absorption bands at 1650 and $1550 cm^{-1}$, which is consistent with the formation of an amide bond. Electroactivity measurements were examined by cyclic voltammogram(CV). These polymers showed the characteristic electrochemical behavior of poly(3-alkylthiophene)s with reversible redox transition in the range of 0.7-0.9 V.

• Textile Coloration and Finishing
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• v.1 no.1
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• pp.63-68
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• 1989

It has been attempted to improve the anti-static property of Nylon 6 by means of Vapor-phase polymerization of thiophene in Nylon 6/PVA blend films impregnated with aluminium chloride as an oxident. After Polymerization of thiophene for two hours in Nylon 6/PVA blend films the conductivity increased from $10^{-12}-10^{-13}S/cm\;to\;10^{-5}-10^{-7}$S/cm, and the conductivity of composite films increased with increasing the concentration of aluminium chloride, the content of PVA annd polymerization time of thiophene. Polythiophene introduced in Nylon 6/PVA blend films has been confirmed by FT-IR spectra and scanning electron micrographs.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.268-269
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• 2008

We have examined the effect of physical drying and annealing conditions for the soluble derivatives of polythiophene as p-type channel materials of organic thin film transistors (OTFTs) in our special designed drying system; performances of the jetting-processed OTFTs can be improved more than 10 times just by optimizing the physical conditions of drying and annealing.