Photoswitchable Covalent Adaptive Networks Based on Thiol-Ene Elastomers

Area of Science:

• Materials Science
• Polymer Chemistry
• Supramolecular Chemistry

Background:

• Covalent adaptive networks (CANs) integrate properties of traditional elastomers and dynamic bonding systems.
• Existing CANs often require complex synthesis or lack rapid responsiveness.
• Thiol-ene chemistry offers a versatile platform for polymer network construction.

Purpose of the Study:

• To develop a straightforward method for creating thiol-ene elastomers with photo-responsive properties.
• To investigate the reversible gel-to-fluid switching behavior induced by UV light.
• To explore the potential of these materials in self-healing, remolding, and adhesive applications.

Main Methods:

• A one-pot synthesis approach was employed to prepare thiol-ene elastomers.
• The elastomers were subjected to UV light irradiation to induce photo-switching.
• The reversibility and cycling stability of the photo-induced switching were evaluated.

Main Results:

• A simple one-pot method successfully produced thiol-ene elastomers exhibiting reversible photoinduced switching.
• The transition from an elastomeric gel to a fluid state occurred rapidly (seconds) upon UV exposure.
• The photo-switching behavior demonstrated high stability, with over 180 repeatable cycles.
• The developed elastomers showed capacity for self-healing, remolding, and reversible adhesion.

Conclusions:

• Thiol-ene elastomers can be readily synthesized to achieve reversible photo-induced gel-fluid switching.
• This photo-switching capability is adaptable across various backbone chemistries and vinyl groups.
• These materials present significant potential for applications requiring dynamic and adaptable material properties.