The effect of vacuum uv-irradiation on the surface energy, solubility and interdiffusion of components in a fluoropolymer-mesogenic monomer-polymer system

The effect of vacuum UV-irradiation on the energy characteristics for the surfaces of films prepared from fluoro-containing polymers, PTFE, and tetrafluoroethylene-hexafluoropropylene copolymer and on the solubilities of a mesogen-containing acrylic monomer and a related LC polymer in these polymers was studied in detail. As a result of modification, the energy characteristics of the surfaces of fluoropolymer films approach the surface characteristics of the films prepared from the monomer and the corresponding LC polymer, while the solubility parameters for the components of these systems level off. The coefficients for diffusion of the monomer and polymer into the said copolymer at 160°C were estimated. It was shown that vacuum UV-irradiation causes a small increase in the diffusion coefficient of the monomer, which is two orders of magnitude higher than that of the corresponding polymer. The possible mechanism for the grafting postpolymerization of the mesogenic monomer on the fluoropolymer films is discussed.