Dielectric Spectroscopy and Synergistic Effects in Epoxy Composites Filled with Multi-Walled Carbon Nanotubes and Carbon-Coated Copper Nanoparticles
Polymer Composites 2024
Dzmitry Tsyhanok, Darya Meisak, Juras Banys, Jan Macutkevič, Algirdas Selskis, Aļisa Šabaļina, Oskars Platnieks, Sergejs Gaidukovs

The electromagnetic properties of epoxy-based composites filled with carbon-coated copper (Cu@C) nanoparticles and multi-walled carbon nanotubes (MWCNTs), along with hybrid MWCNT/Cu@C/Epoxy systems containing varying concentrations of nanoinclusions, were systematically investigated across multiple frequency and temperature ranges. Measurements were conducted in the low-frequency range (20 Hz–1 MHz) and over a temperature span of 40–500 K, as well as in the microwave frequency range (26–37 GHz) at room temperature. The percolation threshold was identified at approximately 2.5 vol% for composites containing only Cu@C nanoparticles and at 0.3 vol% for composites with MWCNTs. Notably, the hybrid MWCNT/Cu@C/Epoxy composites exhibited significantly enhanced electromagnetic properties compared to those of the single-filled systems. At room temperature, an epoxy composite containing 5 vol% Cu@C and 1 vol% MWCNT exhibits a conductivity of approximately 4 × 10−2 S/m, which increases by nearly two orders of magnitude following a thermal cycle up to 500 K. The total electromagnetic interference (EMI) shielding effectiveness in the 26–37 GHz range was measured between 4 and 9 dB, indicating the material's promising potential for attenuating microwave noise. Dynamic mechanical analysis (DMA) results revealed that increasing the MWCNT content improved the storage modulus of the composites but led to a reduction in the glass transition temperature (Tg), which was observed to range between 40 and 50°C. The incorporation of MWCNTs and Cu@C nanoparticles into epoxy matrices offers a promising approach for the development of lightweight multifunctional composites with superior electrical, mechanical, and EMI shielding properties


Keywords
dielectric properties, electrical percolation, epoxy, mechanical analysis, microwave shielding, nanotubes
DOI
10.1002/pc.29337
Hyperlink
https://4spepublications.onlinelibrary.wiley.com/doi/10.1002/pc.29337

Tsyhanok, D., Meisak, D., Banys, J., Macutkevič, J., Selskis, A., Šabaļina, A., Platnieks, O., Gaidukovs, S. Dielectric Spectroscopy and Synergistic Effects in Epoxy Composites Filled with Multi-Walled Carbon Nanotubes and Carbon-Coated Copper Nanoparticles. Polymer Composites, 2024, , pp.1-14. ISSN 0272-8397. e-ISSN 1548-0569. Available from: doi:10.1002/pc.29337

Publication language
English (en)
The Scientific Library of the Riga Technical University.
E-mail: uzzinas@rtu.lv; Phone: +371 28399196