Organosoluble, thermally stable and low dielectric constant fluorinated polyimides containing 2,4,5-triphenylimidazole moiety in the main chains

A photoactive highly fluorinated diamine was synthesized, characterized, and used in preparation of structurally confirmed poly(imidazole-ether-imide)s (PIEIs). These polymers showed excellent solubility, moderate viscosities, good thermal stability (Tg = 230–280 °C, Ti = 390–435 °C, T10% = 480–510 °C), low dielectric constant (2.60–2.76), and water absorptions. The PIEIs films showed highly optical transparency with light transmittance at 550 nm of as high as 80% and cutoff wavelength of as low as 390 nm. These polymers exhibited fluorescence emission peaks around 410–490 nm with the quantum yields measured in solution varied from 12 to 32%.