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Novel highly fluorinated polymers with the benzoxazine moiety in the main chain have been synthesized by incorporating a highly fluorinated diamine with polyfluorinated bisphenol A. The value of the dielectric constant of the step cured polymer film is 2.20. An analogous hydrogenated version, whose dielectric constant value of 2.8 is also synthesized. The molecular structure of the polymers is characterized by NMR and FT-IR and thermal stability by TGA. The dynamic mechanical properties of the polymer step cured under air and under nitrogen are analyzed.

The structural change of chicken egg white lysozyme in aqueous 1-butyl-3-methylimidazolium nitrate ([bmim][NO(3)]) solutions (0-24 M) has been investigated by optical spectroscopy and small-angle X-ray scattering (SAXS) methods. Fourier-transform infrared (FTIR) and circular dichroism (CD) spectra and SAXS profiles indicated that the addition of up to 6 M of [bmim][NO(3)] induces unfolding of lysozyme resulting from disruption of the α-helix by the NO(3)(-) ion. On the other hand, even with the addition of more than 10 M of [bmim][NO(3)], lysozyme aggregation is inhibited and the protein adopts a partially globular state (the secondary structure is partially refolded while the tertiary structure is disrupted). Observation of the structural features of the aqueous [bmim][NO(3)] solution by Raman OD stretching spectra indicated that bulk-like water still remains at concentrations above 10 M and form an "aggregated water" (water pool) in the nanoheterogeneous structure consisting of a polar domain (the high charge-density region) and nonpolar areas (the alkyl-chain region) in the IL. At these concentrations (above 10 M), lysozyme is not sufficiently hydrated because of the reduced number of water molecules. Consequently lysozyme above 10 M assumes the partially globular state. We propose that the changes of the unique IL solution structure (nanoheterogeneous) between the lower and higher [bmim][NO(3)] concentrations strongly correlated to the differences in the protein stability of the present results.

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