Conductivity polythiophene derivatives

Wang C., Schindler J., Kannewurf C., and Kanatzidis. M., Poly(3,4-ethylenedithiathiophene). A new soluble conductive polythiophene derivative, Chem. Mater., 1995, 7, 58-68. 

Wang, C., J.L. Schindler, C.R. Kaimewurf, and M.G. Kanatzidis. 1995. Poly(3,4-ethylenedithiathio-phene). A new soluble conducting polythiophene derivative. Chem Mater 7 58-68. 

Figure 14-21. Variation of the field-effect mobility as a function of the conductivity of variously doped poly(dodecyloxy-terthie-nyl) (PDOT), a polythiophene derivative (adapted from Ref. [113]).

Rud et al. applied electric fields for the improved vertical orientation of SWNTs in a blend with a water-soluble polythiophene derivative [323]. A profound increase of both the conductance and the photocurrent was observed for the devices where CNTs were aligned. The orientation of MWNTs in composites with polymers can also be influenced by application of large magnetic fields [324]. 

Davidson and Ponsonby [55] studied the influence of the degree of crosslinking in a polythiophene derivative on its conductivity (Fig. 9.23(b),). With increasing degree of crosslinking they found an oscillatory behavior of the conductivity. This was explained by a tradeoff between more conductive pathways (good) and less intrachain planarity (bad). 

There were however few exceptions—the most important being polythiophene and poly(p-phenylene vinylene). It was demonstrated [4,5] that in the case of polythiophene, the substitution of hydrogen in the 3 position of the thiophene ring, by an alkyl group longer than the propyl group, renders the polymer soluble in common solvents and the decrease of conductivity in the doped state, caused by the functionalization is rather minor. Since the initial work of Elsenbaumer [4,5] hundreds of papers devoted to soluble polythiophene derivatives have been published. 

IBM introduced a family of polyanilines, referred to as PanAquas , which are highly soluble in neutral water in the conducting form. The PanAqua provides a simple and effective discharge layer for e-beam lithography and can be cleanly removed during the alkaline development of the resist. A water-soluble polythiophene derivative referred to as ESPACER (a trade mark and product of Showa Denko K. K.) is also very effective at eliminating resist charging and can be removed by water wash. 

Polypyrrole and polythiophene derivatives with pendant ferrocene groups (e.g. 2.12) have also been prepared using electropolymerization techniques [35]. Studies of these materials by means of in situ conductivity measurements revealed that the redox conduction, due to hole hopping between the ferrocene units, was en-... 

The logarithm of the room temperature conductivity of the investigated polythiophene derivatives (l)-(4) shows this linear dependence on the minimum interchain distance R as shown in Figure 2... 

A number of other conducting polymer derivatives have been used for immobilizing enzymes and redox mediators for biosensor applications. Among these polymers are poly (tyramine) [167] and poly(l-(5-aminonaphthylethanoic acid) [168], which have accessible amine and carboxyl functionalities, respectively, for covalently linking to complementary groups on available amino acid residues of enzymes. Polypyrrole and polythiophene derivatives have also been widely exploited for covalent immobilization of enzymes, which then function as the sensing layers in efficient biosensors [169,170]. 

Chayer, M., K. Paid, and M. Leclerc. 1997. Highly conducting water-soluble polythiophene derivatives. Chem Mater 9 (12) 2902-2905. 

Tourillon, G., and F. Gamier. 1983. Stability of conducting polythiophene and derivatives. 

Lupu, S., A. Mucci, L. Pigani, R. Seeber, and C. Zanardi. 2002. Polythiophene derivative conducting polymer modified electrodes and microelectrodes for determination of ascorbic acid. Effect of possible interferents. Electroanalysis 14 519-525. 

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