Applications, polymers undoped

In considering the potential applications of electroactive polymers, the question always arises as to their stability. The deterioration of a physical property such as conductivity can be easily measured, but the chemical processes underlying it are not as easy to be revealed. In order to understand them, XPS has been used to follow the structural changes which occur in the polymer chain and the counter-ions of the doped polymer. The following sections present some XPS findings on the degradation of electroactive polymers, such as polyacetylene, polypyrrole, polythiophene and polyaniline, in the undoped and doped states. 

This chapter is not meant to be a comprehensive review of undoped conjugated polymers. Rather, we consider the structural and electronic (mostly spectroscopic) properties of CPs from the perspective of their potential applications in electronics, which are discussed in the final section. 

It should be noted that reinforcement applications are not limited to organic polymers. Though ceramics are already hard and chemically/thermally resistant, these materials may also be doped with CNTs to improve their inherent brittleness. This has already been proven for the incorporation of 5-10% of CNTs within an alumina matrix. The resultant material exhibits five times the fracture toughness and seven times greater electrical conductivity relative to undoped AI2O3, with an added property of unidirectional heat conductivity,... 

M. Schott Undoped (Semiconducting) Conjugated Polymers in Organic Conductors fundamentals and applications (Ed.) J.P. Farges, Marcel Dekker, New York, (1994) p, 539. 

From Table 2.3, which lists typical // values, it can be seen that the hole mobility in conjugated polymers is lower than that in organic crystals and amorphous silicon, but much larger than that in undoped poly(N-vinyl carbazole). Therefore, conjugated polymers have potential for applications in conducting opto-electronic and photonic devices. In principle, this also applies to liquid-crystal systems that can exhibit enhanced molecular order due to their self-organizing ability, as has been pointed out in a progress report [42]. 

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