Synthesis and characterization of semi-fluorinated polyarylene copolymers

A series of semi-fluorinated Diels-Alder polyarylenes copolymers were synthesized by copolymerization of 1,4-bis(2,4,5-triphenylcyclopentadienone) benzene with 1,4-diethynyl-2,3,5,6-tetrafluorobenzene and 1,4-diethynylbenzene as co-monomers. We varied the feed ratio of the fluorinated and fluorine-free diethynylbenzene co-monomers to allow systematic variation in the level of fluorination in the resulting polyarylenes. The semi-fluorinated polyarylene copolymers were characterized by ¹H and ¹⁹F NMR, ATR-FTIR, elemental analysis, TGA, DSC, GPC, and water contact analysis. 19F NMR spectroscopy confirmed the addition of fluorine into the copolymers, while FTIR spectroscopy and elemental analysis established a linear correlation with increasing fluorine content as the feed ratio of the fluorinated monomer increased. Thermal analysis showed little change in the series of copolymers for onset of decomposition (T_d = 550 °C), however, the char yield increased dramatically (55 to 75%). Water contact analysis showed a minimal surface effects for P6 as compared to P1 (90° versus 88°, respectively).