Electrical PANIs

Fig. 1. (a) Comparison of normalised electrical conductivity of individual MWCNTs (Langer 96 [17], Ebbesen [18]) and bundles of MWCNTs (Langer 94 [19], Song [20]). (b) Temperature dependence of resistivity of different forms (ropes and mats) of SWCNTs [21], and chemically doped conducting polymers, PAc (FeClj-doped polyacetylene [22]) and PAni (camphor sulfonic acid-doped polyaniline [2. ]) [24]. 

FIGURE 1.5 (a) Temperature dependence of electric conductivity (b) infrared electric conductivity of PANI-CSA. 

For PLEDs with relatively small active area, the anode can be made of a single layer of conducting polymers with relatively high bulk electric conductivity. Gustafsson and coworkers at UNIAX demonstrated a flexible PLED with conducting PANI-CSA anode, and... 

HRP/IL phase. The electrical conductivity of the PANI films prepared by solvent casting from the aqueous solutions showed a relatively high and similar value even after the fifth run (Fig. 12), which demonstrates the validity of our approach and the ease of recyclability and reuse of the enzyme inside the IL. For the PEDOT, the process of recovery and reuse was successfully repeated up to ten times using the same HRP/EDOT catalytic phase (Fig. 13), further confirming the success of the synthetic approach and the ease of recyclability and reuse of the enzyme inside the EDOT monomer phase. 

PANI is unique in that its most oxidized state, the pernigraniline form (which can be accessed reversibly), is not conducting. In fact, it is the intermediately oxidized emeraldine base that exhibits the highest electrical conductivity. Protonic Acid Doping is the most general means by which to obtain this partially pro-tonated form of PANI [301]. Exposure of the emeraldine salt to alkali solutions reverses this process and brings a return to the insulating state. 

Although the thermal transfer printing technique does not offer resolution as high as pCP, it does have enormous flexibility in the materials that can be patterned. It also benefits from its all dry and purely additive operation it does not require etchants or solution routes for depositing or patterning the key materials. It is necessary, however, to balance the adhesion between the layers that are sequentially transfer such that interfaces have intimate physical and electrical contact. In addition, current commercial systems have pixel sizes of 5 pm x 2.2 pm, which limit the resolution. With the current DNSSA-PANI/SWNT formulation and a printer of this type, it is possible to print 10-pm channels and 25-pm lines. 

Work with PPy and PAni has reached the industrial stage. Bridgestone-Seiko has been selling coin-shaped 3-V polyaniline-based batteries for 5 years (1987-1992), and polypyrrole-based batteries were developed by Varta/BASF in the same period. Such batteries have lower energy densities than those of conventional batteries, but they are superior in terms of selfdischarge. The main characteristics of a typical PAni battery are compared to those of lead and Cd-Ni batteries in Table 4. The values mentioned for energy density and electric capacity density refer to the active material alone. 

The considerable changes in the optical absorption of CPs during the dopingundoping process are at the basis of many proposals for electrochromical devices, such as smart windows, whose light transmission can be electrically controlled, and various display devices. Due to the drastic change that appears in their visible spectrum, PTh [122-124] and PAni [125] are... 

The electrical and electrochromic properties of PANi depend not only on its oxidation state but also on its protonation state, and hence the pH value of the electrolyte used. As shown in Figure 1 PANi exhibits electrochromic behavior. Electrochromic behavior of PANi is shown in Figure 9. As demonstrated, small change in the pH of the solution and/or potential could create color and conductivity changes. PANi is green in the oxidized state and is transparent yellow in the reduced states. It has violet color in very acidic and yellow brownish in very basic media [14-16]. 

A measurement of the optical conductivity of PAni samples over the range 2 meV to leV is illustrated in Fig. 9.38. The reflection spectra were obtained using a Fourier transform interferometer and a synchrotron radiation source. The Kramers-Kroiiig transformation, with appropriate extrapolation of the data to zero and high energy, was used to extract the complex frequency-dependent conductivity and its real part, the optical conductivity. The optical conductivity is related to the imaginary component of the electric susceptibility, since the power dissipated by an optical field of amplitude E is given by ... 

Microspheres have been prepared by the dispersion polymerization of monomers other than vinyl monomers, such as styrene and (meth-)acrylates. Polyaniline (PANI) is one of the most frequently studied electrically conducting polymers. Since the paper by Armes and Aldissi [99] in 1989, there have been numerous reports on the preparation of PANI dispersions by oxidative... 

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