Crosslinkable fluorinated poly(aryl ether ketone)s containing pendent phenylethynyl moieties for optical waveguide devices

A type of novel crosslinkable fluorinated poly(aryl ether ketone) containing pendent phenylethynyl moieties (PEP-3F-PEEKn) have been synthesized by copolycondensation reaction of difluoro-monomer with potassium salt of 4-phenylethynylphenyl hydroquinone (PEP-PH) and (3-trifluoromethyl) phenyl hydroquinone (3F-PH). The resulting polymers could be thermally crosslinked at 370 °C. The cured polymers showed good solvent resistance, high thermal stability up to 500 °C under nitrogen. They had small light absorption at the telecommunication wavelengths of 1.3 and 1.55 μm. The refractive index of the cured films was in the range of 1.6154–1.6274 at 1.55 μm wavelength.