Electret Materials Based on Fluoropolymers Modified with Vanadium- and Phosphorus-Containing Structures

摘要

Organo-inorganic composite materials based on films of polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymer, modified with vanadium- and phosphorus-containing functional groups, were synthesized. The modified fluoropolymer films, especially those modified with phosphorus-containing groups, exhibit increased hydrophilicity. A change in the energy characteristics of the modified films of polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymer, consisting in redistribution of the polar and dispersion constituents of the surface free energy, was revealed. Fluoropolymer samples with the two-component vanadium-phosphorus-containing system in which the phosphorus atoms are located on the surface exhibit the highest polar constituent of the surface energy due to the hydrolytic activity of phosphorus, enhanced by the synergistic effect of vanadium present in the two-component system. Changes in the fluoropolymer surface morphology after the modification were revealed, and the relationship was found between the energy characteristics and morphology of the modified polymer film surface. The electret materials based on modified fluoropolymer films exhibit enhanced charge stability. Films of polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymer with the single-component vanadium-containing system on the surface are the most stable electrets.