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The geometry and magnetic properties of fluorinated radicals RC[F.sub.2]C[F.sub.2] in nafion perfluroinated ionomers were determined by ESR spectra and DFT calculations. The ESR spectrum was accurately simulated by an automatic fitting procedure and DFT calculations supported the pyramidal structure determined by fitting the experimental ESR spectrum.

Spin trapping by 5,5-dimethylpyrroline-N-oxide (DMPO) is used for the detection of radicals in Fenton media in the presence and absence of Nafion perfluorinated ionomers. The formation and trapping of solvent-derived free radicals in ethanol and in methanol is one of the major limitations of DMPO as a spin trap for radical identification in Fenton media, but for water as solvent, the method can be useful when the polymer is treated at higher than ambient temperatures.

ESR spectroscopy is used to detect and identify radicals in Nafion perfluorinated membranes exposed to the Fenton reagent based on Ti(super 3+). In the Fenton reagent (TiCl3 + hydrogen peroxide, no Nafion) radicals were detected only for high concentrations of hydrogen peroxide, 30 percent w/v.

ESR spectra of three fluorinated nitroxide radicals with different lengths of the fluorinated side chain are measured in neat solvents and in Nafion solutions and membranes swollen by water. The assessment of the sensitivity of the probes to the local environment in terms of dynamics and range of the magnetic parameters are studied.

Research is presented describing the use of poly(acrylonitrile-butadiene-styrene) to stablize nitroxide radicals and determine the electron spin resonance imaging.

A pyrene (P), 1,3-bis(1-pyrenyl) propane (P3P) and nitroxide radical 5-doxylstearic acid methyl ester (5DSE) were used in the fluorescence studies of aqueous solutions of poly(ethylene-co-methacrylic acid) ionomers. The P and P3P were used as the luminophores, while the 5DSE was used as the fluorescence quencher. Results showed a high intensity ratio of the third and first vibronic bands and a high microviscosity at the probe site. Moreover, polymeric amphiphiles behave differently from monomeric surfactants in four ways.

One- and two-dimensional (1D and 2D) spectral-spatial electron spin resonance imaging (ESRI) is used for visualizing the dose distribution and linear energy transfer (LET) in a potassium dithionate, [K.sub.2][S.sub.2][O.sub.6] (PDT), dosimeter irradiated with the heavy ions [C.sup.6+] and [N.sup.7+]. The studies have shown that ESRI is promising method determining dose and LET.

Electron spin resonance spectroscopy was used to detect and identify radicals formed by UV irradiation of Nafion and Dow perfluorinated membranes partially or fully neutralized by Cu(II), Fe(II), and Fe(III). The major conclusion obtained was that cations were involved in degradation process where the point of attack appears to be at or near the pendant chain of the ionomer.