Doped poly advantages

Potentiometric sensors responsive to iodide ion that are based on iodine-doped poly(3-methylthiophene) have been demonstrated [214,215]. Potentiometric sensors, because of the wide range of possible potential-influencing interactions [216], offer no major advantages over conventional functionalized nonconducting polymer membranes. 

A more compact reactor design takes advantage of solid polymer electrolytes (SPEs). Hence, cast Nafion membrane and SPEEK were prepared, and used as cationic SPE whereas alkali-doped poly (vinyl alcohol), PVA and Amberlyst resin composites were made, and used as anionic SPE. These SPEs were combined with a cathode made of copper, electrodeposited onto porous carbon paper, and an anode consisting of Pt/C on the carbon paper. The main electroreduction products were formic acid, methanol, formaldehyde, carbon monoxide and methane, while undesired hydrogen gas by-product was also detected [120]. 

Despite their inherent electronic advantages, CT complexes and radical cation salts tend to be brittle and unprocessable. This problem might be overcome by the incorporation of oligomeric tetrathiafulvalenes in polymers, whereby the TTFs can be part of a main-chain or side-chain polymer. The key concern thereby is to achieve the suitable packing of the donor moieties, which is, of course, less perfect than in the crystalline state. Remarkably, the rigid-rod poly-TTF 164 could be made recently by a precursor route in which 164 is made by dimethyl disulfide extrusion of the precursor polymer (scheme 39). The electrical conductivity after iodine doping amounts to 0.6 S/cm [221]. Other examples of TTF-containing polymers, either in the backbone [222] or in the side-chain [223], are summarized in chart 25. 

As the degradation of polyaniline occurs via an imine intermediate [281,284], Kim et al. [285] prepared self-doped polymer by alkylsulphonate substitution in the polymer backbone, Besides self-doping for a facile redox process, the perceived advantage of this bulky substituent includes the protection of nitrogen centres from nucleophiles responsible for irreversible degradation of polyaniline. Poly(aniline N-butylsulphonate) retained its reversible electrochromic response up to 150 000 cycles when scanned between its oxidized and reduced states (between 0.2 and 0.5 V) then started diminishing slowly. The excellent redox cyclability of poly(aniline N-butylsulphonate) over unsubstituted polyaniline was also confirmed by chronoabsorptom-etry by Kim et al. [285],... 

Particle size increases from 100 up to 500 A at use of the mixed catalyst and the increase in density of films is observed. A filtration of suspension it is possible to receive films of any sizes. On the various substrates possessing good adhesive properties, it is possible to receive films dispersion of gel. Polymer easily doping AsF5, FeCl3,l2, and other electron acceptors. Preliminary tests have shown some advantages of such materials at their use in accumulators [48]. Gels poly acetylene with the similar properties. 

Self-doped polyanilines are advantageous due to properties such as solubility, pH independence, redox activity and conductivity. These properties make them more promising in various applications such as energy conversion devices, sensors, electrochromic devices, etc. (see Chapter 1, section 1.6). Several studies have focused on the preparation of self-doped polyaniline nanostructures (i.e., nanoparticles, nanofibers, nanofilms, nanocomposites, etc.) and their applications. Buttry and Tor-resi et al. [51, 244, 245] prepared the nanocomposites from self-doped polyaniline, poly(N-propane sulfonic acid, aniline) and V2O5 for Li secondary battery cathodes. The self-doped polyaniline was used instead of conventional polyaniline to minimize the anion participation in the charge-discharge process and maximize the transport number of Li". In lithium batteries, it is desirable that only lithium cations intercalate into the cathode, because this leads to the use of small amounts of electrolyte... 

---