Light-Dependent RAFT Polymerization of Spiropyran Acrylates

Area of Science:

• Polymer Chemistry
• Photochemistry
• Materials Science

Background:

• Reversible-Addition-Fragmentation chain Transfer (RAFT) polymerization is a controlled radical polymerization technique.
• Spiropyran (SP) moieties can isomerize to merocyanine (MC) forms, potentially interfering with polymerization.
• Controlling SP isomerization is crucial for synthesizing SP-containing polymers.

Purpose of the Study:

• To establish and investigate a light-assisted RAFT copolymerization protocol.
• To synthesize 2-hydroxyethyl acrylate (HEA) / spiropyran acrylate (SPA) copolymers.
• To enhance the incorporation of SPA within the copolymer structure.

Main Methods:

• Utilized a light-assisted RAFT copolymerization approach.
• Employed visible light irradiation during the polymerization process.
• Synthesized copolymers of HEA and SPA.

Main Results:

• Successfully established a light-assisted RAFT protocol for HEA/SPA copolymer synthesis.
• Achieved enhanced SPA content in the resulting copolymers.
• Demonstrated that visible light prevents SP to MC isomerization, avoiding polymerization interference.

Conclusions:

• Light-assisted RAFT polymerization offers a viable method for synthesizing HEA/SPA copolymers with controlled SPA content.
• Visible light irradiation is effective in mitigating side reactions caused by spiropyran isomerization.
• This protocol enables the development of functional polymers with improved spiropyran incorporation.