Intrinsically conductive polymer

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

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

The S-PEEK/HPA composite membranes absorb more water than the pure S-PEEK membranes. The W.U. increase associated with the HPAs incorporation into the S-PEEK matrix is only one of the factors affecting the membrane conductivity. The other factors, including the polymer intrinsic conductivity, the strength, density and softness of the solid acid sites, the solid phase loading, the particle size and spatial distribution, the aqueous phase... 

Conducting polymers (intrinsically conducting polymers, e.g. polyacetylenes (PAC), polypyrroles (PPy), poly thiophenes (e.g poly(3,4-ethylenedioxythiophene) (PEDT), polyanilines (PANI)),... 

During the past 30 years considerable research has been undertaken that has led to electrically conducting polymers that do not rely on the use of fillers, the so-called intrinsically conductive polymers. Such polymers depend on the presence of particles which can transport or carry an electric charge. Two types may be distinguished ... 

The properties and applications of intrinsically conductive polymers have been reviewed (Frommer and Chance, 1986 Sauerer, 1991). The Important poly-pyrolles have been separately reviewed (Jasne, 1988). 

A thin layer deposited between the electrode and the charge transport material can be used to modify the injection process. Some of these arc (relatively poor) conductors and should be viewed as electrode materials in their own right, for example the polymers polyaniline (PAni) [81-83] and polyethylenedioxythiophene (PEDT or PEDOT) [83, 841 heavily doped with anions to be intrinsically conducting. They have work functions of approximately 5.0 cV [75] and therefore are used as anode materials, typically on top of 1TO, which is present to provide lateral conductivity. Thin layers of transition metal oxide on ITO have also been shown [74J to have better injection properties than ITO itself. Again these materials (oxides of ruthenium, molybdenum or vanadium) have high work functions, but because of their low conductivity cannot be used alone as the electrode. 

Phthalocyanines with side groups which can undergo Diels-Alder reactions can be synthesized as precursors for ladder polymers (see pp772, 773).344-345 For these kinds of compounds an intrinsic conductivity is predicted.346 Both dienophilic and enophilic phthalocyanines have been prepared. The possibility to undergo a Diels-Alder reaction was tested with fumaronitrile and 2,3-dimethylbutadiene.345 Via a Diels-Alder reaction, a connection between a phthalocyanine and [60]fullercne was also achieved.336... 

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.)...

H. Naarmann, in Intrinsically Conducting Polymers An Emerging Technology, M. Aldissi, ed., Kluwer, Dordrecht, Netherlands, 1993, p. 1-12. 

Conjugated polymers are generally poor conductors unless they have been doped (oxidized or reduced) to generate mobile charge carriers. This can be explained by the schematic band diagrams shown in Fig. I.23 Polymerization causes the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the monomer to split into n and n bands. In solid-state terminology these are the valence and conduction bands, respectively. In the neutral forms shown in Structures 1-4, the valence band is filled, the conduction band is empty, and the band gap (Eg) is typically 2-3 eV.24 There is therefore little intrinsic conductivity. 

The use of porphyrinic ligands in polymeric systems allows their unique physio-chemical features to be integrated into two (2D)- or three-dimensional (3D) structures. As such, porphyrin or pc macrocycles have been extensively used to prepare polymers, usually via a radical polymerization reaction (85,86) and more recently via iterative Diels-Alder reactions (87-89). The resulting polymers have interesting materials and biological applications. For example, certain pc-based polymers have higher intrinsic conductivities and better catalytic activity than their parent monomers (90-92). The first example of a /jz-based polymer was reported in 1999 by Montalban et al. (36). These polymers were prepared by a ROMP of a norbor-nadiene substituted pz (Scheme 7, 34). This pz was the first example of polymerization of a porphyrinic macrocycle by a ROMP reaction, and it represents a new general route for the synthesis of polymeric porphyrinic-type macrocycles. 

Intrinsically conducting polymers, 13 540 Intrinsic bioremediation, 3 767 defined, 3 759t Intrinsic detectors, 22 180 Intrinsic fiber-optic sensors, 11 148 Intrinsic magnetic properties, of M-type ferrites, 11 67-68 Intrinsic photoconductors, 19 138 Intrinsic rate expressions, 21 341 Intrinsic semiconductors, 22 235-236 energy gap at room temperature, 5 596t Intrinsic strength, of vitreous silica, 22 428 Intrinsic-type detectors, cooling, 19 136 Intrinsic viscosity (TV), of thermoplastics, 10 178... 

Intrinsic conductive polymers (ICP) obtained by polymerization of conductive macromolecules. This is a difficult route for industrial applications. 

Charge-transfer agent used to generate, by oxidation or reduction, positive or negative charges in an intrinsically conducting polymer. 

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 2 Examples of intrinsically conducting polymers are polyacetylene, polythiophene, polypyrrole, or polyaniline. 

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). 

Note 4 An intrinsically conducting polymer should be distinguished from a conducting polymer composite and from a solid polymer electrolyte. 

Aldissi, M. 1992. Intrinsically Conducting Polymers. Kluwer, Dordrecht. 

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