Synthesis and characterization of 4-[(per/polyfluoro)phenyloxy]-4 '-vinylbiphenyls and their polymers

3-Trimethylsilyloxy-3'-vinylbiphenyl was treated with perfluorobenzene, sub stituted polyfluorobenzenes, and perfluoronaphthalene to give 4-[(per/polyf luoro)phenyloxy]-4'-vinylbiphenyls in the presence of catalytic amounts of CsF. The new monomers that resulted were characterized by mass spectra, H-1 and F-19 NMR, and IR spectroscopy. The new polymers obtained by polymerizi ng the monomers using AIBN-initiated free radical polymerization were chara cterized by gel permeation chromatography (GPC), differential scanning calo rimetry (DSC), thermogravimetric analysis (TGA), H-1 and F-19 NMR and IR sp ectroscopies. The polymers were obtained as white powders and were soluble in all common organic solvents. They are thermally very stable and have hig h glass transition temperatures, T-g, i.e. >100 degrees C. Copolymerization of one of the monomers, 4-pentafluorophenyloxy-4'-vinylbiphenyl, 3, with d ifferent molar ratios of methylacrylate gave copolymers that have Low glass transition temperatures compared with the homopolymer of the monomer, 3, a long with very high thermal decomposition temperatures, e.g. incorporation of even a small amount (2.1%) of 3 into the methylacrylate copolymer gave r ise to a 50% char yield at 410 degrees C and a glass transition temperature of 28 degrees C. (C) 1999 Elsevier Science Ltd. All rights reserved.