Investigating mechanical, dielectric, and electromagnetic interference shielding properties of polymer blends and three component hybrid composites based on polyvinyl alcohol, polyaniline, and few layer graphene

Abstract

To achieve the suitable set of synergistic mechanical, dielectric, and electromagnetic interference shielding properties, polymer blends based on varying the concentration of conductive polymer polyaniline (PANI) in insulative matrix of polyvinyl alcohol (PVA) as well as hybrid composites by adding few layer graphene (FLG) in PVA/PANI polymer blends are prepared using solution casting method. In PVA/PANI blends, by increasing the concentration of PANI, dielectric constant (ε′), dielectric loss (ε″), and total shielding efficiency (SET) of PVA are enhanced from 4 to 80, 0.72 to 164, and 2.5 to 30 dB at 100 Hz, respectively, at the considerable loss of its mechanical properties particularly the tensile strength from 23.9 to 8.5 MPa. For hybrid composites of PVA/PANI/FLG, mechanical as well as dielectric and EMI shielding properties are remarkably enhanced at very low loading levels of FLG. The incorporation of small amounts of FLG in PVA/PANI‐10 wt%, the ε′, ε″, and SET are increased from 4 to 7,907, 0.5 to 406,947.5 and 2.5 to 99 dB at 100 Hz, respectively, along with the considerable increase in the mechanical properties such as tensile strength from 15.7 to 36.3 MPa and modulus from 0.1 to 0.96 GPa at the loss of strain. In comparison to PVA/PANI blends, hybrid composites of PVA/PANI/FLG become a promising system for microwave absorption applications. POLYM. COMPOS., 39:3686–3695, 2018. © 2017 Society of Plastics Engineers