Enhanced shielding effectiveness for electromagnetic wave radiation using carbon nanocoil - carbon microcoil hybrid materials

Abstract

The hydrophobic-oleophilic mesh is prepared via simple and environmental friendly method by coating of encapsulation particle. The natural rubber-encapsulated silica ( NR/ SiO 2 ) can undergo the chemical reaction with fluoro-containing chemical under alkaline conditions at 6±2 °C to provide the NR/SiO 2 -encapsulated fluoroalkylsilane. Firstly, the natural rubber was encapsulated with inorganic silica shell using tetraethyl orthosilicate (TEOS) as a silica precursor. The thermal behavior of surface modified natural rubber from thermogravimetric analysis (TGA) showed the thermal stability enhancement of natural rubber after encapsulated with silica shell. The morphology of NR/SiO 2 from TEM image revealed rubber core covered by silica shell. Secondly, the process is integrated between NR/SiO 2 and fluoroalkylsilane group. The coating mesh exhibited hydrophobic-oleophilic characteristic with static water contact angle (WCA) value of 138° and oil contact angle (OCA) of 0°. The surface roughness of mesh from encapsulation particle coating was confirmed by SEM. The coating surface with these encapsulated particles, NR/SiO 2 -encapsulated with trimethoxy( 3,3,3-trifluoropropyl)silane (FAS-3) is applicable to use as coating material for oil/water separation