Polymers (Sep 2022)
Segregated Structure Copolymer of Vinylidene Fluoride and Tetrafluoroethylene Composites Filled with rGO, SWCNTs and Their Mixtures
Abstract
This work is devoted to the formation and study of polymer composites with a segregated structure filled with single-walled carbon nanotubes (SWCNTs), reduced graphene oxide (rGO), and their mixtures. For the first time, polymer composites with a segregated structure filled with rGO/SWCNTs mixtures were obtained. A copolymer of vinylidene fluoride and tetrafluoroethylene (P(VDF-TFE)) was used as a polymer matrix. At a fixed value of the total mass fraction of carbon nanofillers (0.5, 1, and 1.5 wt%), the rGO/SWCNTs ratio was varied. The composites were examined using scanning electron microscopy, wide-range dielectric spectroscopy, and tested for the compression. The effect of the rGO/SWCNTs ratio on the electrical conductivity and mechanical properties of the composites was evaluated. It was shown that, with a decrease in the rGO/SWCNTs ratio, the electrical conductivity increased and reached the maximum at the 1 wt% filling, regardless of the samples’ composition. The maximum value of electrical conductivity from the entire data set was 12.2 S/m. The maximum of elastic modulus was 378.7 ± 3.5 MPa for the sample with 1 wt% SWCNTs, which is 14% higher than the P(VDF-TFE) elastic modulus. The composite filled with a mixture of 0.5 wt% rGO and 0.5 wt% SWCNTs reflected 70% of the electromagnetic wave energy from the front boundary, which is 14% and 50% more than for composites with 1 wt% SWCNTs and with 1 wt% rGO, respectively. The lowest transmission coefficient of ultra-high frequencies waves was obtained for a composite sample with a mixture of 0.5 wt% rGO and 0.5 wt% SWCNTs and amounted to less than 1% for a 2 mm thickness sample.
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