Carbon Black in  Electromagnetic Interference Shielding Effectiveness of Lightweight Polypyrrole  in (C-Band and X-Band) Frequency Range

EMI (Electromagnetic Interference) shielding apeara lot of attention of that electronic devices are being used more widely and reports design progress for shielding..The EMI of PPy/Carbon black synthesized different weight (0,1,3,5 wt.%) of C.B using chemical oxidation method at (3-7)°C and charactrized with X-ray diffraction , Fourier transformation , Field Emission scanning electron microscopy , Electrical conductivity, high Electromagnetic Shielding Effectiveness (SE) in a frequency range of 5.85- 8.2GHz(C-band), 8.20-12.40GHz (x-band),and thermal analyzed using differential thermal analysis(TGA-DSC). FTIR reveal the required functional groups that should be present in all nanocomposites. The dispersion and formed a network of conductive phases that composites had a rough surface and a porous structure of the carbon black particles, according to FESEM results. The PPy /C.B with the A.C conductivity (3.04*10-3 )S/ cm exhibited shielding efficiency SE in (C-band ) at( -33dB) is highly dependent on carbon black and thickness 1.5 mm , with the maximum SE attenuation recorded at 5wt% of carbon black being (-36dB )at 12 GHz. Also in( X-band ) that SE attenuation recorded being at 8GHz . All PPy/C.B nanocomposites exhibit decreasing dielectric properties (ɛ´, ɛ´´, tan δ) with increasing frequency .These nanocomposites demonstrate effective EMI shielding and can be used in various applications such as molecular electronics and microwave absorption materials. Test of TGA-DSC show that exothermic reactions with the dominating weight% take place in ( 25-800) °C, the glass transition temperatures (Tg) at low and high contents of PPy/C.B nanocomposites between ( 110-160 °C ) . The obtained values of Tg showed complete miscibility of most composites. Thermo-gravimetric analysis showed that the Carbon black in polypyrrole nanocomposites formula has highest thermal stability with improved degradation temperature at 660-669 0C at 5% weight loss.