Ionic shape memory polymer gels as multifunctional sensors.

An, YingJun; Yoshida, Haruki; Jing, Yuxin; Liang, Tian; Okuzaki, Hidenori · Soft Matter · 2022

basic_science · Level V

Where this comes from

Abstract

Novel ionic shape memory polymer (SMP) gels were fabricated using SMPs and ionic liquids (ILs) of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) at different weight ratios (<i>W</i><sub>IL</sub>). The shape memory effect and sensor performance of the ionic SMP gels were investigated by means of thermomechanical and mechanoelectrical analyses. It was found that the ionic SMP gel at <i>W</i><sub>IL</sub> = 25 wt% showed a shape memory effect with the shape fixing ratio (<i>R</i><sub>f</sub>) and shape recovery ratio (<i>R</i><sub>r</sub>) of 72.7% and 72.9%, respectively. Upon bending, the ionic SMP gel sensors with PEDOT:PSS electrodes generated an open circuit voltage of 3.3 mV and a charge of 1.6 nC which linearly increased with increasing bending displacement and velocity, respectively. Furthermore, the wearable shape memory multifunctional sensor array was demonstrated as a self-powered motion sensor for IoT applications.