Optical dispersion of radiation-grafted fluoro-polymer

Controlling the index of refraction of polymers plays an important role in their advanced nonlinear optical and electro-optical applications as well as in nanophotonics and biophotonic technologies. A radiation-induced grafting of acrylic acid (AAc) onto poly(tetrafluoroethylene-co-perfluorovinyl ether) (PFA) copolymer films was carried out to synthesize graft copolymer films using gamma-irradiation by the mutual method. The resulted films were characterized by Fourier transform infrared spectroscopy. The grafting process is associated with cross-linking through which a considerable change in the material refractive index is achieved. The linear refractive index, optical dispersion, and the quantum parameters of grafted poly(tetrafluoroethylene-co-perfluorovinyl ether) (PFA-g-PAAc) polymeric film are determined in a wide spectral range of 0.2-3 microm. The wavelength for zero material dispersion is evaluated. The oscillator, dispersion, and lattice energies, respectively, are calculated revealing the optical properties of the studied trunk polymeric substrate and the grafted ones. The origin of the optical properties has been discussed.