Highly sensitive large strain cellulose/multiwalled carbon nanotubes (MWCNTs)/thermoplastic polyurethane (TPU) nanocomposite foams: From design to performance evaluation

Aerogel-based polymer composite foams are promising for large strain piezoresistive sensors, but their aerogel skeleton is partially destroyed during the foaming process, limiting their sensitivity. Herein, the thermoplastic polyurethane was synthesized on the aerogel skeleton to obtain cellulose/multiwalled carbon nanotubes (MWCNTs)/thermoplastic polyurethane (TPU) nanocomposite materials foamed with the aid of supercritical carbon dioxide (ScCO2). A series of lightweight, high strength, and high sensitivity nanocomposite foams were developed, possessing an average diameter of similar to 9.11 mu m and a cell density of 6.84 x 10(8) cells/cm(3). The mechanical properties, including compressive strength and compressive modulus, were promisingly 5.56 and 28.90 MPa, respectively. Under 50 % strain, apparent high repeatability of force-to-electricity conversion behavior was detected in 100 compression cycles.