• Macromolecular Research
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• v.12 no.3
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• pp.303-310
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• 2004

We have prepared an aqueous dispersion of poly(aniline-dodecyl benzene sulfonic acid complex) (PANI-DC) that has an intrinsic viscosity (〔η〕) near 1.3 dL/g using aniline as a monomer, dodecyl benzene sulfonic acid(DBSA) as a dopant/emulsifier, and ammonium peroxodisulfate(APS) as an oxidant. We found that the electrical conductivity of a PANI-DC pellet was 0.7 S/cm. A waterborne-polyurethane (WBPU) dispersion, obtained from isophorone diisocyanate/polytetramethylene oxide glycol/dimethylol propionic acid/ethylene diamine/triethylene amine, was used as a matrix polymer. We prepared blend films of WBPU/PANI-DC with variable weight ratios (from 99/1 to 66/34) by solution blending/casting and investigated the effects that the PANI-DC content has on the mechanical and dynamic mechanical properties, hardness, electrical conductivity, and antistaticity of these films. The tensile strength, percentage of elongation, and hardness of WBPU/PANI-DC blend films all decreased markedly upon increasing the PANI-DC content. The antistatic half-life time ($\tau$$\sub$$\frac{1}{2}$/) of pure WBPU film was about 110 s, but we found that those of WBPU/ultrasound-treated PANI-DC blend films decreased exponentially from 1.2 s to 0.1 s to almost 0 s upon increasing the PANI-DC content from 1 wt% to 15 wt% to > 15 wt%, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.12
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• pp.1044-1048
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• 2007

With development of electronic products the demands for miniaturization and weight-lightening have increased until a recent date. Accordingly, The effort to substitute glass substrates was widely made. However, polymer substrates have weak point that substrates were damaged at high temperature. In this paper, we deposited transparent conductive film at low temperature. And we inserted Au thin film between oxide to compensate for deteriorated electrical characteristics. Ga-doped ZnO(GZO) multilayer coatings were deposited on glass substrate by DC sputtering. The optimization of deposition conditions of both AZO and Au layers were performed to obtain better electrical and optical characteristics in advance. We presumed that the properties of multilayer were affected by the deposition process of both GZO and Au layers. The best multilayer coating exhibited the resistivity of $2.72{\times}10^{-3}\;{\Omega}-cm$ and transmittance of 77 %. From these results, we can confirm a possibility of the application as transparent conductive electrodes.

• Elastomers and Composites
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• v.46 no.4
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• pp.290-294
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• 2011

The surface resistance of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT/PSS), which has appeared to be one of the most successful conductive polymers, is affected by the solvent. In this paper, pellet-type PEDOT/PSS was suspended in $H_2O$, ethanol (EtOH), ethylene glycol (EG) or dimethylsulfoxide (DMSO), and coated on PET film. The surface resistances of the films made from EG or DMSO suspension were observed to be lower, nearly by 2 orders of magnitude, than that made from $H_2O$ suspension. No significant difference among four kinds of films was observed when the thermal properties and chemical structures were investigated by TGA and XPS, respectively. However, particle size of PEDOT/PSS was in the range of $1-3{\mu}m$ in EG or DMSO, on the other hand, less than $0.1{\mu}m$ in $H_2O$. It is considered that the particle size of PEDOT/PSS in the suspension plays an important role for the surface resistance.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.411-416
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• 2010

In this research, we intended to improve the tolerance of thick film resistor using photosensitive polymer resistor paste which was fabricated with alkali-solution developable photosensitive resin and conductive carbon black. At first, we investigated the effect of the selection of carbon black and photosensitive resin on the resistance range and tolerance level of polymer thick film resistor (PTFR). And then, a difference in resistance tolerance was evaluated according to the coating methods of photosensitive resistor paste on test board. In case that the photosensitive resistor paste was coated on whole surface of test board using screen printing, large positional tolerance was obtained because the formation of the thick film with uniform thickness was difficult. On the other hand, when the paste was coated with roller, the resistive thick film with uniform thickness was formed on the whole board area and the result of resistance evaluation showed low tolerance in ${\pm}10%$ range. The tolerance of PTFR could be improved by combination of the precise patterning using photo-process and the coating process for the resistive thick film with uniform thickness.

• Applied Chemistry for Engineering
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• v.24 no.2
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• pp.196-200
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• 2013

We conducted investigation on polymeric binders for anti-static coating agent which can maintain stability under the high-voltaic condition. Various polyesters composed of polyethylene glycol (PEG) and polypropylene glycol (PPG) were synthesized and studied in term of the variation in the surface resistance of the film made from coating solution composed of a conductive polymer and these polyesters as a binder. We found that the surface resistance displayed $10^7{\sim}10^8{\Omega}/{\square}$ regardless of chemical composition of binders under the potential of 10 V. Whereas, the surface resistance surged to higher than $2{\times}10^{10}{\Omega}/{\square}$ when 1000 V was applied, rendering it improper for anti-static purpose. When 1,4 butanediol (BD) was incorporated into polyesters ([PEG]/[PPG]/[BD] = 25.0/67.5/7.5), the surface resistance showed $2.8{\times}10^9{\Omega}/{\square}$ under 1000 V, acceptable for anti-static application. These observations may indicate that the hydrophobic nature of BD makes a significant contribution to the surface resistance at a high positive potential.

• Applied Chemistry for Engineering
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• v.26 no.4
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• pp.458-462
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• 2015

It is essential to employ a binder to prepare transparent films from conductive polymer such as poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT/PSS). In this paper, poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), and PSS were selected as a binder, and their effects were investigated. The formation of the film was found to be primarily dependent on the surface tension of coating solution including PEDOT/PSS and a binder. When PSS was used as a binder, the film was not formed. In case of using PVP, it was easily peeled off from the substrate. However, when using the PVA or the mixtures of PVA and PSS or PVA and PVP as a binder, films with good transparency and uniform surface resistances were produced. Based on adhesion and long-term stability tests, we concluded that the mixture of PVA and PSS is the best binder for preparing antistatic films of PEDOT/PSS.

• Membrane Journal
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• v.33 no.5
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• pp.248-256
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• 2023

Indium tin oxide (ITO) transparent electrode film has been widely adopted for the various applications such as display and electric vehicle. In this paper, we studied how to enhance the thermoforming stability of ITO film by applying the highly conductive Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin layer. Based on the change of sheet resistance value, the influence of the additional solvent with different boiling point was investigated for the PEDOT:PSS coating solution. In addition, by analyzing optical transmittance and Raman spectrum, we confirmed the key mechanism which determine the final electrical conductivity of the PEDOT:PSS on ITO film using an ethylene glycol solvent. The final ITO transparent electrode coated with PEDOT:PSS performed the outstanding endurance of electrical conduction even in 126% stretching condition.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.381-385
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• 2022

It is very important to secure the adhesion durability between the base film and the conductive paste for the development of a sensor for detecting hazardous chemicals. In this study, an ester binder was used to improve the adhesive properties which can be a problem when applying the sensor to the cross cut 0B or 1B grade. This problem was found while evaluating the adhesive properties by coating the polyaniline/graphene nano plate (GNP) paste on the polyethylene terephthalate (PET) film. When 10 wt% or more of the ester-based binder was added, the cross cut grade to which the sensor can be applied was 3B or higher. It was confirmed that the excessive addition of the binder may affect the electrical properties of the conductive paste and actually decrease the reactivity to sulfuric acid. To improve the electrical property, a carbon black (CB) content was varied resulting in the optimum electrical property observed at 2 wt% of CB.

• Industry Promotion Research
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• v.9 no.1
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• pp.21-29
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• 2024

In the rapidly advancing information society, electronic devices, including smartphones and tablets, are increasingly digitized and equipped with high-performance features such as flexible displays. This study focused on optimizing the manufacturing process for Transparent Conductive Films (TCF) by using the cost-effective conductive polymer PEDOT and transparent substrate PET as alternatives to expensive materials in flexible display technology. The variables considered are production speed (m/min), coating maximum temperature (℃), and PEDOT supply speed (rpm), with surface resistivity (Ω/□) as the response parameter, using Response Surface Methodology (RSM). Optimization results indicate the ideal conditions for production: a speed of 22.16 m/min, coating temperature of 125.28℃, and PEDOT supply at 522.79 rpm. Statistical analysis validates the reliability of the results (F value: 18.37, P-value: < 0.0001, R²: 0.9430). Under optimal conditions, the predicted surface resistivity is 145.75 Ω/□, closely aligned with the experimental value of 142.97 Ω/□. Applying these findings to mass production processes is expected to enhance production yields and decrease defect rates compared to current practices. This research provides valuable insights for the advancement of flexible display manufacturing.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3109-3114
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• 2010

Flexible composite films of $V_2O_5$ and conductive polypyrrole ($V_2O_5$/PPy) were grown by facile electrochemical polymerization, wherein an anodization potential was applied to the substrate electrode in an electrolyte solution containing pyrrole monomer and dispersed $V_2O_5$ particles. The coating of polypyrrole (PPy) on the surface of $V_2O_5$ particles was induced by the oxidative catalytic action of $V_2O_5$ during the electrochemical polymerization of pyrrole. PPy in the composite film connects the isolated $V_2O_5$ particles. This results in the formation of conductive networks in the composite film cathode, thereby enhancing the Li+ ion diffusion to the surface of the isolated $V_2O_5$ particles and thus increasing the accessibility of the $Li^+$ ions. The specific capacity tests of the Li rechargeable batteries revealed that the discharge capacity of this composite film cathode was higher, i.e., $497\;mAhg^{-1}$, than that of $V_2O_5$/PPy powder or pristine $V_2O_5$.