title: Composites prepared from the waterborne polyurethane cationomers-modified graphene. Part II. Electrical properties of the polyurethane films.
abstract: The research was planned to test electrical properties of polymer films made from polyurethane cationomers with 0-2 wt.% graphene admixture. The cationomers were synthetized in the reaction of 4,4'-methylenebis(phenyl isocyanate), polycaprolactone diol (M= 2000),N-methyldiethanolamine, and formic acid. It was found that addition of approx. 2 wt.% of graphene causes the loss of volume resistivity by three orders of magnitude and percolation threshold is already set at approx. 1 wt.%. The frequency characteristic of a real part of permittivityε' and imaginary part of permittivityε″ were measured for the tested films. On the base of Havriliak-Negami equation, parameters of relaxation functions in frequency domain were estimated for samples containing various contents of graphene. The influence of the cationomer phase structure on observed changes of dielectric losses coefficient tgδ in the full-measuring frequency spectrum was discussed.
authors.affiliation: Department of Polymer Science, Faculty of Chemistry, Rzeszów University of Technology, Al. Powstańców Warszawy 6, 35-959 Rzeszów, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Król
authors.affiliation: Department of Polymer Science, Faculty of Chemistry, Rzeszów University of Technology, Al. Powstańców Warszawy 6, 35-959 Rzeszów, Poland.
authors.forename: Bożena
authors.initials: B
authors.lastname: Król
authors.affiliation: Faculty of Electrical Engineering, Department of Electrotechnology and Diagnostic, West Pomeranian University of Technology, Szczecin, Ul. Sikorskiego 37, 70-313 Szczecin, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Zenker
authors.affiliation: Faculty of Electrical Engineering, Department of Electrotechnology and Diagnostic, West Pomeranian University of Technology, Szczecin, Ul. Sikorskiego 37, 70-313 Szczecin, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Subocz
keywords: Dielectric constants ε′ and ε″ in frequency domain; Dielectric losses coefficient tgδ; Havriliak–Negami equation; Volume resistivity