Poly(spiro[2,4]hepta-4,6-diene) (PSHD) was exposed to oxidants such as bromine, iodine and antimony pentachloride either in solution or as a film. Bromine was rapidly added to the C--~C bonds of the polymer. Heating the brominated polymer to elevated temperatures resulted in dehydrobromination and the formation of a conjugated, unsaturated polymer backbone, recognizable by the formation of a black, insoluble product. Exposure of PSHD to iodine or antimony pentachloride led to the formation of a black product with a metallic appearance. The conjugation length of the resulting oxidized polymer was rather short. From optical absorption spectra a length of six to eight C~---~C bonds could be deduced. Infra-red spectra indicated that oxidation was accompanied by a cleavage of the cyclopropyl groups. The oxidized polymer was electrically conducting. Maximum conductivities of 10- 5 S cm- ~ were obtained when PSHD was exposed to iodine vapour for several hours. From electron spin resonance studies it could be derived that the conductivity is due to an electron-hopping process.
Посилання на статтю:
Conducting polymers from poly (spi ro [ 2,4 ] hepta-4,6-d iene ) / Bernd Tieke* and Sheik A. Zahir // Polymer. – 1994. – Vol 35. – P. 2467-2471.