On the absorption dominated EMI shielding effects in free standing and flexible films of poly(vinylidene fluoride)/graphene nanocomposite

• Published in: European polymer journal 2018-02, Vol.99, p.437-444
• Main Authors: Sabira, K., Jayakrishnan, M.P., Saheeda, P., Jayalekshmi, S.
• Format: Article
• Language: English
• Subjects: Absorption; Absorption loss; Adsorption; Beta phase; Conductivity; Electrical resistivity; Electromagnetic shielding; Electromagnetics; EMI shielding; Fourier transforms; Graphene; Infrared analysis; Magnetic shielding; Nanocomposites; Polyvinylidene fluorides; Scattering parameters; Shielding effectiveness; Stealth applications; Thermal stability; Thickness; Vinylidene fluoride; X-ray diffraction
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2017.12.034

[Display omitted] •PVDF/graphene nanocomposite films were obtained by a simple method.•These free-standing films exhibit high EMI shielding effectiveness as high as 47 dB.•The absorption dominated EMI shielding is of significance in stealth applications.•These flexible films are mechanically and thermally stable. The present work highlights the remarkably high electro-magnetic interference (EMI) shielding effectiveness of about 47 dB, exhibited by highly conducting and ordered poly(vinylidene fluoride) (PVDF)/graphene nanocomposite films of thickness around 20 µm, in the microwave frequency range 8–12 GHz, obtained by solution casting method. The films were characterized structurally using X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy and the analysis indicates the enhancement in the highly ordered β phase of PVDF with the incorporation of graphene. In the entire frequency range of analysis, by absorption loss to the total EMI shielding effectiveness is very high compared to that by reflection loss. The high electrical conductivity of the composite films promotes shielding by absorption losses which is of ample significance in stealth applications. The present results identify the PVDF/graphene nanocomposite film as an effective, lightweight, free standing, flexible, mechanically and thermally stable, absorption dominated EMI shielding material with application prospects in a broad range of electromagnetic spectrum. The shielding effectiveness of these highly conducting nanocomposite films, far exceeds most of the previously reported values and meets the commercial requirements. The freestanding and flexible nature of these films facilitates EMI shielding applications without the geometrical constraints of the shape or size of the object.