Bioinspired Conductive Enhanced Polyurethane Ionic Skin as Reliable Multifunctional Sensors

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemistry

Background:

• Ionogels offer advantages over hydrogels, including no evaporation and stable performance.
• Traditional ionogels suffer from low conductivity due to bulky ions hindering migration within polymer networks.

Purpose of the Study:

• To develop ultradurable ionogels with enhanced mechanical properties and high electrical conductivity.
• To mimic biological ion transport channels for improved ion migration.

Main Methods:

• Impregnating ionic liquid (IL) into a water-based polyurethane (WPU) network.
• Utilizing carboxylic acid in WPU's hard segment to form ionic conduction channels via hydrogen bonding.
• Mimicking ion transport channels found in phospholipid bilayers.

Main Results:

• Achieved ionogel conductivities exceeding 28-39 mS cm⁻¹.
• Developed ionogels with adjustable mechanical properties (Young's modulus: 0.1-0.6 MPa), comparable to natural skin.
• Demonstrated ultrahigh sensitivity (0.99-1.35) in strain sensors with a wide sensing range (0.1%-200%).

Conclusions:

• The novel WPU-based ionogels exhibit superior conductivity and tunable mechanical properties.
• The biomimetic design effectively creates ionic conduction channels, enhancing ion transport.
• These ionogels show significant promise for environmentally stable and high-conductivity ionotronic applications.