Conjugated polymers containing phenothiazine moieties in the main chain

Several conjugated polymers containing phenothiazine moieties in the main chain were synthesized by Knovenagel or Wittig condensations. The polymers were identified and characterized by H-1-NMR, IR, gel permeation chromatography (GPC), thermogravmetric analysis (TGA), UV-vis and fluorescent (FL) spectra. Results indicated that the m-polymer, which was prepared from the polycondensation of N-octyl-3,7-diformylphenothiazine with m-phenylene diacetonitrile, is the most thermally stable one in all the polymers synthesized. While, the p-polymer, which was prepared from the polycondensation of N-octyl-3,7-diformylphenothiazine with p-phenylene diacetonitrile, is the most thermally instable one. The introduction of a cyano group made the absorption and emissive maxima red-shift from 429 and 537nm for the Ph-polymer to 465 and 597nm for the p-polymer respectively. The quinoid structure formation allows the p-polymer to have a lower band gap than any other polymers. Emissive spectra of all these polymers in tetrahydrofuran (THF) solution have a narrow half-peak width. Copyright (c) 2006 John Wiley & Sons, Ltd.