• Bulletin of the Korean Chemical Society
• /
• v.30 no.7
• /
• pp.1543-1546
• /
• 2009

Temperature and frequency dependent AC conductivity behavior has been studied for the chemically synthesized polyaniline-polymannuronate (PANI-PM) composites. The temperature (300 - 500 K) and frequency (100 - $10^6$ Hz) dependent AC conductivity suggests evidence for the transport mechanism in PANI-PM composites. The frequency dependence of AC conductivity has been investigated by the power law. The frequency exponent (s) is determined, and the data suggest that s decreases with temperature. The variation of s with temperature suggests that AC conduction is due to the correlated barrier hopping.

• Macromolecular Research
• /
• v.17 no.8
• /
• pp.609-615
• /
• 2009

Two types of nano composite were obtained by in situ chemical method in polyaniline (PANI)/dodecyl-benzenesulfonic acid (DBSA) system depending on the use of either ammonium persulfate (APS) or ferric chloride ($FeCl_3$) as the oxidant. In order to study the difference of the two composites in the surface characteristics, thermal stability, and electric properties, the composite films were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and temperature dependent DC electrical conductivity. The results revealed a large difference in the surface morphology, thermal stability, and the microstructure properties between the two composites, and these differences were considered responsible for the molecular order and conductivity.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.9
• /
• pp.1699-1704
• /
• 2008

• Applied Chemistry for Engineering
• /
• v.16 no.1
• /
• pp.1-8
• /
• 2005

Electrorheological (ER) fluids, typically composed of particles having higher dielectric constant or electric conductivity than that of suspending fluids with a low viscosity, undergo dramatic, reversible changes when exposed to an external electric field. Among various electroactive materials, we put our efforts on inorganic materials including zeolite, MCM-41, MCM-41/polyaniline composite and SBA-15/polyaniline composites. Their preparation and ER characteristics are introduced.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.10
• /
• pp.2967-2972
• /
• 2010

Poly-N-vinylcarbazole/polyaniline (PVK-PANI) composites are synthesized by varying target loading concentrations of aniline (0.025 - 0.1 M). The surface morphology of the composites is studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The temperature-dependent DC conductivity of PVK-PANI composite films was studied at the temperature range of 300 - 500 K. The data suggest that the conductivity increase with an increase in aniline concentration in the composite with an increase in temperature. Further based on the conductivity behavior we can suggest that the PVK-PANI composites show a semiconducting behavior with a positive temperature coefficient of resistivity (TCR). The enhanced conductivity and the positive TCR of the PVK-PANI composite films may be due to the strong interaction between PANI and PVK in the composite films.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.12
• /
• pp.2423-2426
• /
• 2008

• Proceedings of the Korean Magnestics Society Conference
• /
• 2007.05a
• /
• pp.250.1-250.1
• /
• 2007

• Proceedings of the Korean Fiber Society Conference
• /
• 2007.11a
• /
• pp.503-504
• /
• 2007

• Proceedings of the Korean Society of Rheology Conference
• /
• 2002.11a
• /
• pp.85-88
• /
• 2002

No Abstract, See Full Text

• Proceedings of the Korean Society of Rheology Conference
• /
• 2001.09a
• /
• pp.160.3-160
• /
• 2001