Semi-IPN ionogel based on poly (ionic liquids)/xanthan gum for highly sensitive pressure sensor

In this paper, a novel ionogel with semi-interpenetrating poly (ionic liquids)/xanthan gum (PIL/XG) polymer network (semi-IPN) was prepared by using a simple one-pot method. The structure and the pressure sensing performance have been systematically investigated. It was found that introducing a low content (0.3-3.1 wt%) of XG significantly promoted the mechanical performance of ionogels with little effect on the ionic conductivity. The optimized PIL/XG containing 2.2 wt% XG exhibited high compression strength (761.0 kPa) and ionic conductivity (0.63 S/m at 25 °C). Such ionogels showed a liner response (0-100 kPa) and high sensitivity value of 6.86 kPa^-1 in a capacitive mode. Meanwhile, as a resistive sensor, PIL/XG exhibited a wide response range to dynamic pressure ranges with stable repeatability. Furthermore, this ionogel exhibited excellent bactericidal properties against both gram-positive bacteria and gram-negative bacteria. This research provides a potential approach for developing ionogels based on semi-IPN with pressure-sensitive and anti-bacterial properties.