Stretchable electromagnetic-interference shielding materials made of a long single-walled carbon-nanotube–elastomer composite

Abstract

By using long single-walled carbon nanotubes that possess a high aspect ratio and small diameter as fillers, we introduced electromagnetic interference (EMI) shielding to a fluorinated rubber without hardening and embrittling it. A sheet of this material with a thickness of 0.2 mm could decrease more than 90% of the strength of incident electromagnetic waves at microwave frequencies. Further, this material has a sufficient flexibility, which enables it to elongate to double its original length without any cracking, and has a higher mechanical strength than commercialized generic stocking (3.1 times the maximum tensile stress and 2.4 times the tear strength). Therefore, this material is useful for flexible and stretchable EMI shielding sheets that can wrap an arbitrarily shaped radiating object. This feature can be attributed to the fact that the carbon nanotubes could induce EMI shielding at a low loading level (only 1 wt%) without breaking the structure of the rubber matrix.