Surface-Activated Phenol-Urethane Elastomer Enabling Tough, Adhesive, and Conductive Interfaces for Stretchable...

Area of Science:

• Materials Science
• Polymer Chemistry
• Electronics Engineering

Background:

• Interfacial mismatch between soft substrates and rigid components limits stretchable hybrid electronics (SHEs) reliability.
• Achieving both high bulk strength and strong interfacial adhesion in SHEs is challenging.

Purpose of the Study:

• To develop a surface activation strategy for self-adhesive and conductive stretchable conductors.
• To enable direct, plug-and-play attachment of rigid electronic devices to soft substrates.
• To enhance the mechanical properties and interfacial adhesion of SHEs.

Main Methods:

• Designed a dynamic bisphenol polyurethane elastomer (BPU) with programmable phenol-urethane bonds.
• Activated the BPU surface using ethanol-vapor treatment.
• Constructed a semi-embedded conductive network using silver nanowires (Ag NWs) via thermal reorganization.

Main Results:

• The activated BPU surface exhibited a peeling strength of 10.5 N/cm.
• Achieved stretchable conductors with low sheet resistance (11 Ω/sq) and strong adhesion (7.75 N/cm).
• The prepared SHEs demonstrated high stretchability (≈270%) and stable conductivity after 4000 cycles at 30% strain.

Conclusions:

• Surface activation based on dynamic phenol-urethane bond exchange effectively strengthens soft/hard interfaces in SHEs.
• The developed BPU elastomers offer tunable mechanical properties and robust adhesion.
• This approach enables reliable and high-performance stretchable hybrid electronics.