Photo-crosslinking polymers by dynamic covalent disulfide bonds

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Chemistry

Background:

• Developing polymers with tunable properties is crucial for advanced material applications.
• Photo-crosslinking offers precise control over polymer network formation.
• Reversible crosslinking enables material reprocessing and recycling.

Purpose of the Study:

• To present a general strategy for creating photo-crosslinkable polymers.
• To utilize natural thioctic acid for polymer modification.
• To achieve efficient photo-crosslinking and reversible decrosslinking in polydimethylsiloxane (PDMS).

Main Methods:

• Synthesizing polymers with sidechain 1,2-dithiolane groups derived from thioctic acid.
• Employing disulfide five-membered rings as photo-responsive crosslinking units.
• Investigating the photo-crosslinking and decrosslinking behavior of modified PDMS.

Main Results:

• Successfully introduced 1,2-dithiolane units into polymer sidechains.
• Demonstrated that disulfide rings function as both light absorbers and dynamic covalent crosslinkers.
• Achieved efficient photo-crosslinking of PDMS polymers.
• Showcased reversible chemical decrosslinking of the crosslinked polymer network.

Conclusions:

• The presented strategy provides a simple and general method for constructing photo-crosslinkable polymers.
• Thioctic acid-based dithiolanes are effective for light-induced crosslinking and reversible decrosslinking.
• This approach offers potential for creating adaptable and recyclable polymer materials.