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Cobalt Ferrite/Polyetherimide Composites as Thermally Stable Materials for Electromagnetic Interference Shielding
Mihai Asandulesa1, Corneliu Hamciuc1, Aurel Pui2
1"Petru Poni" Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania.
International Journal of Molecular Sciences
|January 21, 2023
Summary
New polyetherimide (PEI) composites with cobalt ferrite (CoFe2O4) nanofillers effectively shield electromagnetic interference (EMI). These materials offer high thermal stability and enhanced conductivity for electronic applications.
Area of Science:
- Materials Science
- Nanotechnology
- Electromagnetism
Background:
- Automated industries generate electromagnetic interference (EMI), impacting electronic devices and users.
- Polyetherimide (PEI) is a polymer matrix, and cobalt ferrite (CoFe2O4) is a magnetic nanoparticle filler.
Purpose of the Study:
- To develop novel PEI/CoFe2O4 composites for effective EMI shielding.
- To investigate the influence of CoFe2O4 nanofiller content on composite properties.
Main Methods:
- Composites were synthesized by incorporating CoFe2O4 nanoparticles into a PEI matrix via poly(amic acid) solution, followed by film casting and thermal imidization.
- Materials were characterized using magnetic analysis, electrical conductivity measurements, and thermal stability tests.
Main Results:
- The PEI/CoFe2O4 composites demonstrated high thermal stability (decomposition onset 450-487 °C).
- Magnetic properties included saturation magnetization of 27.9 emu/g at 50 wt% CoFe2O4.
- Electrical conductivity increased significantly with nanofiller content, reaching 1.70 x 10^-8 S/cm at 50 wt% CoFe2O4 (1 MHz).
Conclusions:
- The developed PEI/CoFe2O4 composites exhibit promising electromagnetic interference shielding capabilities.
- These materials possess a combination of desirable thermal, magnetic, and electrical properties for EMI shielding applications.
Keywords:
broadband dielectric spectroscopyelectromagnetic shieldingmagnetic fillerpolyetherimidethermal stabilityMore Related Videos
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