Highly Stretchable and Self-Healable Graphene-Encapsulated Liquid Metal Composites for Multifunctional Applications.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Liquid metal (LM) polymer composites face challenges with network formation and leakage due to LM's shape and fluidity.
• Existing composites struggle to achieve efficient conductivity at low LM content and prevent leakage at high content.

Purpose of the Study:

• To develop a high-performance liquid metal-based polymer composite using graphene nanosheets (GNS) for enhanced electrical conductivity, anti-leakage, stretchability, and self-healing properties.
• To create a hybrid network of GNS and LM within a supramolecular polyurethane-urea (PUU) matrix.

Main Methods:

• Encapsulation of liquid metal (LM) droplets with graphene nanosheets (GNS) to form GNS@LM.
• Fabrication of GNS@LM/PUU composites by incorporating GNS@LM into a supramolecular polyurethane-urea matrix.
• Characterization of electrical conductivity, anti-leakage behavior, stretchability, and self-healing properties.

Main Results:

• A composite with 2.0 vol% GNS achieved a superior electrical conductivity of 548.1 S/m at 25 vol% GNS@LM.
• Excellent anti-leakage behavior was observed at 45 vol% GNS@LM content.
• The GNS@LM/PUU composite exhibited high stretchability (902.4% strain) and self-healing efficiency (96.0% conductivity recovery at 80°C for 24h).

Conclusions:

• Graphene nanosheets effectively bridge liquid metal droplets, forming efficient conductive pathways and preventing leakage in polymer composites.
• The developed GNS@LM/PUU composite demonstrates exceptional multifunctional properties, including high conductivity, stretchability, and self-healing.
• This facile strategy offers a promising route for fabricating advanced liquid metal-based composites for integrated electronics, thermal management, shielding, and Joule heating applications.