An Elastic Autonomous Self-Healing Capacitive Sensor Based on a Dynamic Dual Crosslinked Chemical System

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Wearable electronics require robust and stretchable materials for enhanced durability and functionality.
• Existing self-healing materials often lack sufficient elasticity and mechanical strength, limiting their application.
• Substrate materials are crucial components in devices like touch screens and soft robotics.

Purpose of the Study:

• To design and synthesize a novel material with both autonomous self-healing properties and excellent elasticity.
• To overcome the limitations of current self-healing materials regarding mechanical performance.
• To demonstrate the material's potential in fabricating advanced electronic components.

Main Methods:

• A multiphase separated polymer network was created using dynamic metal-coordinated bonds (β-diketone-europium interaction) and hydrogen bonds.
• The material's mechanical properties, including stress at break and fracture strain, were characterized.
• Self-healing efficiency was quantified after a defined period without external stimuli.
• Stretchable and self-healable dielectric and conductive layers were fabricated using the developed polymer system and silver composite.

Main Results:

• The developed material exhibits a high stress at break (≈1.8 MPa) and a high fracture strain (≈900%).
• The substrate achieved up to 98% self-healing efficiency within 48 hours at 25 °C autonomously.
• A stretchable and self-healable dielectric layer and conductive layers were successfully fabricated.
• Capacitive sensors were created using these materials, demonstrating a functional stretchable and self-healable touch pad.

Conclusions:

• The novel polymer network effectively integrates self-healing and high elasticity through dual-dynamic bonding.
• The material's robust mechanical properties and autonomous repair capability make it suitable for next-generation electronic applications.
• This work presents a significant advancement in developing advanced materials for stretchable and self-healing devices.