Shielding Effectiveness, Mechanical and Dielectric Properties of NiO/PCL Nano Composites at Microwave Frequency for Electronic Devices

Abstract

There is a continuous generation of electromagnetic fields through operations of electronic devices for this reason it is paramount that these fields be shielded so as to prevent interferences. The, conventional method for shielding these fields are by the use of thin metal foils or sheets. The metals foils are heavy, difficult to fabricate, costly and in many cases not suitable for use in many applications. For these reasons, this work is focused on using materials that is flexible, cost effective and durable, with considerable shielding effectiveness (SE). Hence, polycaprolactone (PCL) and nickel oxide (NiO) nanocomposite were synthesized using the conventional melt blending (CMB) technique. The synthesis method used is fast, easy and produces large mass of controlled composites within a short period. Rectangular waveguide, vector network analyzer, coaxial cable and open ended coaxial probe were used in the measurement of microwave properties. Measured scattering parameter was used to calculate the shielding effectiveness of the NiO/PCL composites. Findings indicates that the dielectric constant increased with increasing filler content, where the highest dielectric property was 5.09 for the 62.5 % filler and it was able to shield electromagnetic fields by up to -9.35 dB at the frequency range measured. The average particle size of the NiO nano particles was 40.5 nm using TEM analysis. The best hardness and tensile strength was recorded for the highest loading percentage. It is then concluded that the substrate produced can be tailored for electronic, telecommunication, medical applications and military shield applications.

Synthesis and Characterization of Hematite Fe2O3 Nanofiller for Enhanced Dielectric and Microwave-Absorbing Properties in PTFE Composites

“…These materials can effectively absorb electromagnetic waves and reduce EMI in electronic devices. Microwave absorbers (MA) are specifically designed to suit the needs of maintaining excellent absorption at a broad frequency range, having a thin thickness that can enhance microwave absorption properties [1], [2].…”