Synthesis and properties of wholly aromatic polymers bearing cardo fluorene moieties

[[abstract]]Three series of aromatic polyamides, polyesters, and poly(1,3,4-oxadiazole)s containing bulky fluorene structures were prepared from 9,9-bis(4-carboxyphenyl) fluorene. All of the polymers were readily soluble in many organic solvents and showed useful thermal stability associated with high glass-transition temperatures in the range of 220-366 degrees C. These wholly aromatic polymer films were colorless, with high optical transparency, and exhibited UV-vis absorption bands at 266-348 nm and photoluminescence maximum bands at 368-457 nm within the purple to green region in N,N-dimethylacetamide (DMAc) solutions. The poly(amine-amide) Ic exhibited excellent electrochromic contrast and coloration efficiency, changing color from the colorless neutral form to green and then to the dark blue oxidized forms with good stability of electrochromic characteristics. Almost all of these wholly aromatic polymer films were colorless and showed high optical transparency. (c) 2007 Wiley Periodicals, Inc.[[note]]SC