Large cyclic deformability of microcellular TPU/MWCNT composite film with conductive stability, and electromagnetic interference shielding and self-cleaning performance

Materials with those characteristics of lightweight, thin, deformable, conductive stability, and self-cleaning have a nice application foreground in flexible conductive field. Herein, the thin and lightweight material with effectively bonded surface of carbon nanotube is prepared by carbon dioxide foaming technology that is environmentally friendly and simple process. The base material is selected from an elastomer, that is, thermoplastic polyurethane, which promotes the prepared cellular material with 0.6 mm thickness to have good flexibility and contact comfort. The material undergoes multiple cyclic tensile deformations under 100% strain, resulting in low hysteresis and residual strain. After 12 h of recovery time, the material can almost return to its original length. For these excellent deformation capabilities, the cellular structure introduced inside the material matrix plays a crucial role. Based on exactly the same reason, after 50 cycles of cyclic tensile process, the designed material's conductivity has not changed significantly before and after deformation, ensuring the stability of the conductive performance under multiple large deformations. The EMI SE after cyclic deformations is further promoted to be 18 dB. Moreover, the bonding layer on the material surface effectively shows good self-cleaning ability, and water contact angle is about 130 degrees.