Conductive Filler‐Loaded PVDF and Pristine PVDF ‐Layered Composite for EMI Shielding and as Piezoelectric Sensor

Abstract

ABSTRACT The present study aims at the fabrication of conductive filler (GNP and MWCNT) loaded hybrid PVDF and pristine PVDF layered composite for the multi‐purpose applications as electromagnetic interference (EMI) shield in 8 to 12 GHz (X‐band), 12 to 18 GHz (Ku‐band) and 18 to 26 GHz (k‐band) frequency range and as a piezoelectric sensor. It is observed that the hot‐pressed pristine PVDF results in a dominant β‐phase responsible for the piezoelectric effect. The electrical conductivity of the GNP (10 wt%) and MWCNT (5 wt%) loaded PVDF (G10‐C5) sample is close to 1.78 S/m and is therefore used as electrodes sandwiching the hot‐pressed pristine PVDF layer for piezoelectric and EMI shielding applications. This three‐layered sample has a thickness of about 0.5 mm. The layered PVDF sample was found to have a better EMI shielding of 20.4, 24.8, and 26.1 dB in the X, Ku, and K bands, respectively, indicating 99.5% of an incident electromagnetic wave does not pass through the sample. Furthermore, the layered PVDF sample is tested under fatigue cyclic load, and the measured output voltage is directly proportional to the compression force; it is also capable of capturing machine vibrations. The maximum output voltage attained under the compression of 150 N is 4 V. Hence, it is summarized that the fabricated PVDF sample can be used as a gasket material, which can attenuate EM waves and also be used for piezo sensing.