Electronically Intrinsically Conducting Polymers

Conducting polymers (CPs) are very popular matrices suitable for biomolecule immobilization in biosensors [44]. They show a suitable flexibility and can be chemically modified as required. The advantage of CPs is that their electrochemical synthesis allows direct deposition of a polymer on the electrode surface while 

---

Figure 20. Artificial muscle under work. In reduction (A) electrons are injected into the polymer chains. Positive charges are annihilated. Counter-ions and water molecules are expelled. The polymer shrinks and compaction stress gradients appear at each point of the interface of the two polymers. The free end of the bilayer describes an angular movement toward the left side. (B) Opposite processes and movements occur under oxidation. (Reprinted from T. F. Otero and J. Rodriguez, in Intrinsically Conducting Polymers An Emerging Technology, M. Aldissi, ed., pp. 179-190, Figs. 1,2. Copyright 1993. Reprinted with kind permission of Kluwer Academic Publishers.)...

Note 1 The bulk electrical conductivity of an intrinsically conducting polymer is comparable to that of some metals and results from its macromolecules acquiring positive or negative charges through oxidation or reduction by an electron acceptor or donor (charge-transfer agent), termed a dopant. 

Note 3 Unlike polymeric electrolytes, in which charge is transported by dissolved ions, charge in intrinsically conducting polymers is transported along and between polymer molecules via generated charge carriers (e.g., holes, electrons). 

In this paper we report on the synthesis of new types of intrinsically conducting polymers using high-temperature reaction of condensation polymers and polyfunctional monomers. We shall show that the new polymers can be regarded as low-dimensional graphites both macroscopically and microscopically and discuss the change in their structural and electronic properties with heat-treatment temperature (HTT). 

Intrinsically conducting polymers are a broad class of (often) processable materials based upon doped -it conjugated polymers. Their conductivities vary from that of insultators through to that of semiconductors and even good metals. A wide variety of electronic phenomena are observed. Because of the broad choice of materials and properties, this class of polymer is potentially of use in a large number of technologies. 

The research of the conductivity phenomena of the new materials category of the class of intrinsically conductive polymers proceeded from the paradigm that the transport phenomena were linked to the properties of the polymer chain. This began with the hypothesis that polyacetylene was an ideal candidate for the search for solitons. The oxidation, which was incorrectly called doping , of the chain of the original non-conductive polymer made possible a kind of folding over of the conjugated double bonds, thereby the flow of electrons was set in motion and the intrinsical conductive polymer was bom. 

Although the electronic conductivity of an interphase that is present on an electrode can be related to various optoelectronic properties that are also measurable with spectroscopic techniques, the direct measurement of surface conductivities is not a spectroelectrochemical method. It is nevertheless a surface sensitive method that provides results closely related to those of other methods discussed in this book. Data on the electrosorption of alcohols on gold electrodes [45] or the electrode potential dependent conductivity of intrinsically conducting polymers [46] have been obtained with in situ surface conductivity measurements. Figure 4.4 shows the electrical resistance of a poly(2-propylaniline) film measured in situ under experimental conditions suppressing any influence of solution phase conduction. The influence of... 

Beyond numerous studies of soluble reaction intermediates and products (as an example see a study of electroreduction of nitrosobenzene [23] or investigations of chromium aryl complexes [24]) this design has also been employed successfully in studies of polymer films deposited onto these electrodes. Films showing redox activity and, in many cases, intrinsic electronic conductivity [intrinsically conducting polymers (ICPs)] have been studied for an overview see [25, 26]. In a typical set of spectra (Fig. 5.5) obtained with a film of poly aniline, optical absorptions corresponding to the 7T 7T transition (around 330 nm) and to further transitions involving species like radical cations (polarons) and dications (bipolarons) formed in the sequence of electrooxidation of the film are observed. 

Later, these intrinsically conducting polymers were improved and a new generation of processahle, and air stable conducting (thermoplastic) polymers were introduced, and found immediate applications in electronics industry as electrodissipating packages , [18]. 

Poly-acetylene is an insulator, but it can be transferred by oxidation into an electronic conductor. These intrinsically conducting polymers will be described in Chapter 11. 

Electronically Conducting Polymers (Intrinsically Conducting Polymers—ICPs) 15... 

Electronically Conducting Polymers (Intrinsically Conducting Polymers—ICPs) does not participate in the polymerization reaction [319] ... 

---