Single wall carbon nanohorn (SWCNH)/graphene nanoplate/poly(methyl methacrylate) nanocomposites: a promising material for electromagnetic interference shielding applications

Single wall carbon nanohorn (SWCNH)/graphene nanoplates (GNP)/poly(methyl methacrylate) (PMMA) nanocomposites were prepared through addition of GNP/PMMA bead into the SWCNH dispersed PMMA matrix during its polymerization. Three dimensional continuous network of GNP-SWCNH-GNP or SWCNH-GNP-SWCNH has been formed throughout the PMMA matrix outside the GNP/PMMA beads that played a crucial role for high electrical conductivity and electromagnetic interference shielding effectiveness (EMI SE) in the nanocomposites. Thus, high electrical conductivity (4.54 x 10(-2) S cm(-1)) and high EMI SE value similar to(-23.6 dB) were achieved in the nanocomposites even at a low loading of SWCNH and GNP. The ratio of volume (vol%) and weight (wt%) of the all the components (SWCNH : GNP : PMMA) in the final nanocomposites were 1.072 : 0.089 : 98.839 and 1.0 : 0.175 : 98.825, respectively. The GNP/PMMA beads act as excluded volume and also attenuates the microwave energy through multiple reflections. The nonconductive GNP/PMMA beads also create dielectric mismatch which influences the internal multiple reflection property of the nanocomposites.