Reprocessable, Highly Transparent Ionic Conductive Elastomers Based on β-Amino Ester Chemistry for Sensing Devices.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Ionic conductive elastomers (ICEs) are promising for stretchable electronics due to their combined ionic conductivity and elasticity.
• Reprocessing ICEs without performance degradation remains a significant challenge.
• Covalent adaptable networks (CANs) offer a potential solution for creating reprocessable materials.

Purpose of the Study:

• To develop reprocessable ionic conductive elastomers (ICEs) using covalent adaptable networks (CANs).
• To investigate the properties and performance of these new materials in sensing applications.
• To demonstrate the feasibility of reprocessing ICEs without compromising their functionality.

Main Methods:

• Incorporation of β-amino ester bonds as dynamic motifs into poly(ethylene oxide) networks containing LiTFSI salt.
• Preparation of LiTFSI-containing β-amino ester networks (LBAEs).
• Characterization of LBAEs' transparency, thermal stability, conductivity, mechanical properties, and viscoelastic behavior.
• Application testing in human motion sensing devices.
• Evaluation of material performance after multiple reprocessing cycles.

Main Results:

• LBAEs exhibited excellent transparency (94%) and thermal stability (>280 °C).
• Modest ionic conductivity (0.00576 mS·cm^-1 at 20 °C) was achieved, with tunable properties via lithium salt content.
• Operational capability was maintained across a wide temperature range (-20 to 100 °C).
• Successful application in human motion sensing devices (finger bending, swallowing, clenching).
• Structural integrity and operational capability were retained after four reprocessing cycles.

Conclusions:

• The developed LBAEs offer a viable solution for reprocessing challenges in flexible conductive devices.
• The integration of CANs and ICEs provides a novel pathway for creating sustainable and high-performance stretchable electronics.
• These reprocessable ICEs hold significant promise for advanced sensing applications and electronic devices.