Injectable, Tough, and Thermoplastic Supramolecular Hydrogel Coatings with Controllable Adhesion for Touch Sensing

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Soft tissues rely on load-bearing structures for support.
• Hydrogel coatings offer unique properties but lack comprehensive performance when combined with robust substrates.
• Mimetic hydrogel coatings require further development for advanced applications.

Purpose of the Study:

• To fabricate an injectable, tough, and thermoplastic supramolecular hydrogel coating.
• To achieve temperature-controlled adhesion for versatile substrate integration.
• To develop hydrogel coatings for functional touch sensing devices.

Main Methods:

• Fabrication of κ-carrageenan (κ-car)/poly(N-acryloyl glycinamide)-co-vinyl imidazole (PNV) supramolecular hydrogel.
• Characterization of hydrogel properties including sol-gel transition temperature, compressive and tensile strain, self-recovery, and durability.
• Evaluation of temperature-controlled adhesion and slide rheostat-based touch sensing capabilities.

Main Results:

• The κ-car/PNV hydrogel (9:1 NAGA:VI ratio) exhibited a sol-gel transition at 85 °C.
• Achieved high compressive (99%) and tensile (1045%) strain, demonstrating toughness and elasticity.
• Successfully demonstrated temperature-controlled adhesion to irregular substrates and stable touch sensing performance.

Conclusions:

• The developed supramolecular hydrogel coating provides a versatile platform for advanced applications.
• This material integrates functional hydrogels, surface coatings, and ionotronics for touch sensing.
• Facilitates the fabrication and application of hydrogel coatings in wearable electronics and biomimetic systems.