Fabrication of Core–Shell Nanohybrid-Structured Hydrogel Sensors with Desirable Mechanical and Antibacterial Properties by Quaternary Ammonium Ionic Liquids with Different Chain Lengths

Hydrogel sensors have found widespread applications in
various
research areas, including medical monitoring devices, smart robots,
and so on. However, traditional hydrogels usually suffer from poor
mechanical strength and durability, which shorten their service life.
Inspired by the toughening mechanisms, we successfully synthesized
polyaniline-coated silica (SiO2@PANI) core–shell
particle-toughened p(AM/DMx) (quaternary ammonium ionic liquids, DMx) hydrogel with different chain lengths. More importantly,
we investigated different chain length effects on the mechanical properties
and antibacterial activity of the DMx-based
hydrogel. We found that the optimum chain length was C12, the maxi tensile strength of the hydrogel was 307
kPa, the ultrahigh conductivity was 12.77 mS/cm, and the hydrogel
exhibited high sensitivity (GF = 12.75) and excellent antimicrobial
properties, which established its potential for usage in a wide array
of applications. The p(AM/DM12)-SiO2@PANI hydrogel sensors can sensitively and stably detect human
activities, such as finger, wrist, and arm flexion. Furthermore, the
obtained hydrogel sensors have the potential to be used in the manufacture
of a generation of human activity monitors, electronic skins, and
soft electronic devices.