Oxidized multiwall carbon nanotube/silicone foam composites with effective electromagnetic interference shielding and high gamma radiation stability

Oxidized multiwall carbon nanotubes (o-MWCNTs) were introduced into silicone foam to fabricate an electromagnetic interference (EMI) shielding material with high gamma radiation stability by solution casting followed by foaming and cross-linking reactions. The as-prepared o-MWCNT/silicone foam composites exhibited excellent mechanical strength and effective EMI shielding properties with superior EMI shielding effectiveness (SE) ranging from 26 to 73 dB at a 0.5-6.4 mm thickness with 30 wt% o-MWCNTs in the K-u band. Moreover, the composites have good gamma radiation stability, showing relatively stable EMI shielding properties and an improvement of hardness and pressure resistance after gamma irradiation with the absorbed dose of 500 kGy. These results indicate that the o-MWCNT/silicone foam composite is an attractive candidate for EMI shielding in some ionizing radiation environments.