Polypyrrole polythienylene

Polymers in this category are of interest in that they can be easily synthesized, being of very high stability. A couple of these polymers are illustrated in Fig. 16. Poly(p-phenylene) is prepared by the polymerization of benzene with A1C13 and CuCl2 (Kovacic and Kyriakis, 1963 Kovacic and Oziomek, 1964), whereas polypyrrole and polythienylene are prepared by the electrochemical polymerization of each monomer with an appropriate electrolyte (Diaz et al., 1979 Tourillon and Gamier, 1982). Polythienylene is also synthesized by the polycondensation of dihalo-thiophene (Yamamoto et al., 1980). 

Polypyrrole and polythienylene (Fig. 16) have the same number of tt electrons as poly(p-phenylene). The electronic structure of polypyrrole has been examined by several authors (Ford et al., 1982 Br6das et al., 1983a). The HO and the LU bands are of tt nature. The orbital pattern of the HOMO accompanied by the top of the valence band has no contribu-... 

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