Poly(cycloalkyl[c]thiophene)s — syntheses, electrical properties and charge transport mechanism

✍ Scribed by Jürgen Rühe; Anna Berlin; Gerhard Wegner

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 800 KB
• Volume: 196
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1995.021960115

✦ Synopsis

Poly(cycloalkyl[c] thiophene)~ were synthesized by electrochemical or chemical oxidation of bicyclic, a,a'-unsubsituted thiophenes. NMR measurements on neutral, soluble poly(cyc1ododeca[c]thiophene) indicate that the polymers have the expected linear structure. The optical spectra and the electrochemical properties of the films are reported. The electrical conductivity u of salts of the polymers varies from 50 S/cm to 8. lo-' S/cm depending on the ring size of the substituent and degree of oxidation of the polymer backbone. A linear correlation between log u and the diameter of the alkyl substituent demonstrates that interchain contacts play a dominant role in the conductivity of these polymers. The temperature dependence of the conductivity was measured in the range of 300 to 5 K and its frequency dependence in the range of 1 -lo7 Hz at 300 to 120 K. The conductivity data were analyzed in terms of hopping of localized charge carriers and the localization length of the charge carriers was calculated.