Ultra-Tough and Highly Stretchable Dual-Crosslinked Eutectogel Based on Coordinated and Non-Coordinated Two Types...

Area of Science:

• Materials Science
• Polymer Chemistry
• Soft Matter Physics

Background:

• Eutectogels are promising for flexible devices due to ionic conductivity and biocompatibility.
• Existing eutectogels often lack sufficient mechanical strength and toughness.

Purpose of the Study:

• To develop ultra-tough and highly stretchable polyacrylamide (PAM) eutectogels.
• To enhance mechanical properties through a dual-crosslinking network.

Main Methods:

• Polymerization of acrylamide in a mixture of coordinated metal salt-type and non-coordinated choline chloride (ChCl)-type deep eutectic solvents (DES).
• Utilizing metal coordination bonds and hydrogen bonds for physical cross-linking alongside chemical cross-linking.
• Adjusting the molar ratio of DES components to tune mechanical properties.

Main Results:

• Achieved high tensile strength (2.9–8.2 MPa) and elongation at break (1725–747%).
• Demonstrated reversible non-covalent crosslinking, enabling self-recovery and self-healing.
• Exhibited excellent ionic conductivity (3.56 mS cm⁻¹).

Conclusions:

• The developed dual-crosslinked eutectogels overcome the limitations of low strength and toughness in existing materials.
• The strategy is versatile for creating tough eutectogels with various metal ions and polymers.
• These eutectogels show potential for flexible electronics, particularly as strain sensors for human motion detection.