Flexible, compressible, hydrophobic, floatable, and conductive carbon nanotube-polymer sponge

A flexible, compressible, hydrophobic, ice-repelling, floatable, and conductive carbon nanotube (CNT)-polydimethylsiloxane (PDMS) sponge is presented. The microporous sponge-like PDMS scaffold fabricated with a sugar cube template is capable of CNT uptake. The CNT-PDMS sponge (CPS) is deformable and compressible up to 90%. The Young's modulus varies from 22KPa to 200KPa depending on the applied strain. The conductive pathways via the CNT network increase with compressive strain similar to a variable resistor or pressure sensor. The softness of the CPS can be utilized for artificial skin to grip sensitive objects. In addition, the contact angle of water droplets on CPS shows 141 degrees, and thus the hydrophobic nature of the CPS can be exploited as a floating electrode. Furthermore, the hydrophobicity is maintained below freezing temperature, allowing an ice-repelling electrode. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790437]