• Journal of Sensor Science and Technology
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• v.9 no.3
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• pp.208-212
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• 2000

A protein based vision biomembrane was fabricated by adsorbing bacteriorhodopsin into electrochemically polymerized polypyrrole film substrate mainly through strong electrostatic interaction. The immobilized bacteriorhodopsin on the polypyrrole film was demonstrated by SEM and SRET. The light signal transducing function from the bacteriorhodopsin which was adsorbed into Polypyrrole film was evaluated by electroretinogram(ERG). A wave form analysis of the electroretinogram indicated that the adsorbed bacteriorhodopsin retained its activity and light signal was obtained from the protein for at least one month.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.178-179
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• 2006

나노 크기를 가지는 DNA 분자를 template로 사용하여 전도성 고분자의 일종인 polypyrrole nanowire를 합성하였다. 본 논문에서 합성된 polypyrrole nanowire는 단량체인 pyrrole과 산화제와의 화학적인 반응에 의해 만들어졌다. 먼저 DNA 분자를 APTES(3-aminopropyltriethoxysilane) modified Si surface 위에 정렬한다. 그리고 이 기판을 농도를 달리한 pyrrole solution에서 incubationn한다. 마지막으로 APS (ammonium persulfate)와 반응시켜 conductive nanowire를 합성하였다. SEM을 이용하여 silicon 기판위에 1차원적으로 정렬된 나노 크기를 가지는 polypyrrole nanowire를 관찰할수 있었다. 그리고 pyrrole의 농도에 따라 nanowire의 uniformity를 조절할 수 있었다.

• Journal of Mechanical Science and Technology
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• v.19 no.10
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• pp.1910-1918
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• 2005

Characterizing electrochemical polymerization of polypyrrole film on a substrate depends on many parameters. Among them, potential difference and cumulative charges play important role. The level of potential difference affects the quality of the polypyrrole. On the contrary, cumulative charge affects the thickness of the polypyrrole. The substrate surface is adjusted physically and chemically by treating with sandblasting and the addition of thiol for surface adhesion improvement. Experimental results show that the sandblasted and thiol treated substrate provides better. adhesion than non-sandblasted and non-thiol treated substrate.

• Macromolecular Research
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• v.10 no.4
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• pp.181-186
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• 2002

The displacement of carbon black to polypyrrole as a catalyst supporter in the fuel electrode of a direct methanol fuel cell was investigated. Polypyrrole was obtained as a black powder by the chemical polymerization of pyrrole with three different oxidants. The synthesized polypyrroles were pasted on carbon paper and transformed to the fuel electrodes with electrochemically deposited platinum. The prepared fuel electrode was assembled and mounted in a unit cell using a membrane and cathodic electrode film. In comparison with the carbon black fuel electrode, the performance of the unit cell was analyzed in relation to the state of the catalyst, the type of oxidant, and the morphology of the polypyrrole powder.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1815-1818
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• 2006

Imogolite which has chemical composition, $(HO)_3Al_2O_3SiOH$, was synthesized with orthosilicate acid and aluminium chloride at low pH solution. It has extremely large aspect ratio with an external diameter of 2nm and the length of a few micrometers. The high aspect ratio of the imogolite could make the material as the filler for the high strength fiber and as the wire for the electronic applications. Here, Imogolite that derives considerable microporosity from a nanometer-sized tubular structure has been modified with a conducting polymer, polypyrrole. Its bonding and wiring structure were confirmed by IR and TEM. The measured conductivity after modification with polypyrrole increased with polypyrrole thickness at various voltage conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.109-110
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• 2007

Pyrrole and DNA can be used for synthesis of conducting nanowires. Protonated pyrrole and negatively charged DNA are absorbed by electrostatic interaction. The level of absorbance is related to pH of pyrrole. Therefore, DNA immobilized and aligned on the 3-aminopropyltrimethoxysi1ane (APTES) modified Si surface. Positive pyrrole monomers was deposited on aligned DNA for the synthesis of nanowire in various pH condition. And polypyrrole nanowires were synthesized by polimerization with ammonium persulfate (APS). These polypyrrole nanowires were measured by AFM, and then we found optimal pH level for the synthesis of nanowires.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.544-547
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• 2000

Polypyrrole (PPy) was chemically synthesized within the pores of nanoporous polycarbonate (PC) Particle Track-etched Membranes (nano-PTM). Hollow tubules are formed because polypyrrole initially deposits on the surface of the pores walls. By running successive syntheses, we have obtained wires (filled tubules). The redox property of PPy nanotubules was investigated by cyclic voltammetry. The redox potential was lowered as much as 0.5V vs. Ag/AgC1, comparing with electrosynthesized PPy film. It suggests that an electron hopping mechanism of PPy nanotubules was improved. Electric conductivity of PPy nanotubules and nanowire was evaluated. We obtained good electric conductivity of PPy nanotubules even in the neutral state. The conductivity and activation energy were $10^1$ order at the room temperature and 25.3 meV respectively.

• Textile Coloration and Finishing
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• v.2 no.1
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• pp.31-36
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• 1990

The electrically conducting cellulose acetate/polypyrrole composite films were synthesized by exposing cellulose acetate film containing oxidizing agent to pyrrole vapour and the formation of polypyrrole is confirmed by IR and electron microscopic studies. The morphologies of polypyrrole in the composites are different depending on the oxidizing agent. Ferric chloride is most effective among several metallic chlorides to synthesize the composites with high electrical conductivity. The conductivity of composite films synthesized with 50 wt.% of ferric chloride reaches upto $10^{-2}S/cm$.

• Elastomers and Composites
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• v.56 no.4
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• pp.250-253
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• 2021

Polypyrrole is an organic thermoelectric material which has been receiving extensive attention in recent years. Polypyrrole is applicable in various fields because its electrical properties are controllable by its doping concentration. In this study, the effects of the polypyrrole doping state on its photoresponse were investigated. The degree of doping was controlled by ammonia solution treatment. Then, the chemical structure as a function of the doping states was observed by Raman analysis. Moreover, the photocurrent and photovoltage characteristics for various doping states were measured by an asymmetrically irradiated light source. As the degree of doping increased, the electrical conductivity increased, which affected the photocurrent. Meanwhile, the photovoltage was related to the temperature gradient caused by light irradiation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.6
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• pp.520-525
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• 2000

Glucose oxidase was immobilized in polypyrrole by electrosynthesis. The enzyme had an influence on the redox properties of a complex enzyme electrode. In the cyclic voltammograms of the enazyme electrode new peaks were appeared at the potential around 0.7V vs. Ag/AgCl in additional to the typical peaks for polypyrrole. The more immobilized the stronger the peaks became. During the cycling the pH of electrolyte solution was decreased to about 4.4 The reason for that is to be the proton released from the carboxyl in the glucose oxidase in order to keep on a charge neutrality of the oxidized enzyme. This fact suggests that the new peaks in the voltammograms are caused by the redox of glucose oxidase. In the AC impedance spectrum analysis of the electrode the diffusion of electrolyte anion was limited because of chained structure of the enzyme. The faradic impedance was large since the glucose oxidase is an insulator. Therefore when glucose oxidase is entrapped the enzyme should be limited in amount. Because the growth of the polypyrrole is accompanied both charge transfer and mass transport. For the traditional electrosynthesis that means amount of enzyme present in the electrode is limited to as much as film growable.