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Energy characteristics of the irradiated surface of a polytetrafluoroethylene film depend on the energy and fluence of bombarding MeV protons. Irradiation with 2-4 MeV protons leads to an increase in the surface free energy; 4 MeV protons at a fluence of 1015 proton/cm2 increase the polarity of the polymer surface by 40 times due to the appearance of functional groups, the polarity enhancement being manifested in an increase in the acid-base component of the surface energy by more than a factor of 50. There is a correlation between the dispersion component of the surface energy and the degree of crystallinity of the near-surface layer of the polymer a period. They both grow symbatically in the case of bombardment with 1-2 MeV protons and decrease upon irradiation with 4 MeV protons. It has been found that dehydrofluorination results in carbonization of the irradiated surface, a decrease in the fluorine content, and an increase in the proportion of oxygen due to oxidation of the radicals generated by proton bombardment. [ABSTRACT FROM AUTHOR]

The irradiation of low-density polyethylene with MeV protons leads to a substantial increase in surface free energy, its acid-base component, and surface polarity due to the appearance of functional groups in the surface layer, as confirmed by ATR IR and Raman spectra. It has been shown that the surface energy of the irradiated polymer depends little on the change in proton energy from 1 to 4 MeV at a fluence of 1015 proton/cm2. It has been found that the oxygen content of the irradiated polymer surface increases as a result of oxidative reactions of the radicals generated during radiolysis and the thermal stability of the polymer decreases. [ABSTRACT FROM AUTHOR]

The action of accelerated 1–4-MeV protons on polychlorotrifluoroethylene in vacuum was accompanied by a preferential rupture of the main polymer chain with the release of more than 30 gaseous products, most of which were tetrafluoroethylene and chlorine- and fluorine-containing compounds. As a result of proton bombardment, the concentration of carbon on the polymer surface decreased and the concentrations of fluorine and chlorine increased. It has been shown that the incorporation of chlorine atoms into the structure of a perfluoropolymer changes the mechanism of its proton bombardment and helps to protect its macromolecule from the reaction of fluorine abstraction by accelerated protons with the formation of hydrogen fluoride. It has been found that irradiation with accelerated protons leads to changes in surface energy characteristics. [ABSTRACT FROM AUTHOR]