Synthesis and characterization of high thermally-stable and good soluble PVK-based polymers with perylene moiety

Three new poly(N-vinylcarbazole) (PVK)-based copolymers containing N-(n- butyl)-N-ethyl-1,6,7,12-tetra- (4-tert-butyl-phenoxy)-3,4,9,10-perylene tetracarboxylic bisimides were successfully synthesized by partially formylated by the standard Vilsmeier reaction, and the formyl groups of high reactivity are condensed with cyanoacetylated perylene to afford PVK-based polymers. The copolymers containing different percentage of perylene were obtained through the percentage of cyanoacetylated perylene unit being controlled by the initial feed ratio. The structures and properties of three copolymers were characterized and evaluated by FT-IR, NMR, UV-vis, FL spectroscopy, gel permeation chromatography, and thermogravimetric analysis measurements. The polymers were highly soluble in conventional solvents such as toluene, CHCl3, THF, DMF etc., and they were thermally stable up to 442-445 degrees C. Three copolymers have emission spectra with characteristic features of the perylene unit, and fluorescence quantum yields of polymers are higher than that of perylene bisimide, which may be caused by singlet-singlet energy transfer from PVK backbone to perylene in the polymers. (C) 2008 Wiley Periodicals, Inc.