Fully oxygen-tolerant atom transfer radical polymerization triggered by sodium pyruvate

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Synthesis

Background:

• Atom transfer radical polymerization (ATRP) is a powerful reversible deactivation radical polymerization (RDRP) technique.
• Conventional ATRP methods suffer from poor oxygen tolerance, limiting their application in ambient conditions.
• The need for oxygen-free environments restricts the practical utility and scalability of ATRP.

Purpose of the Study:

• To develop a fully oxygen-tolerant ATRP process.
• To enable controlled polymerization in both aqueous and organic solvents under open-vessel conditions.
• To overcome the limitations of traditional ATRP regarding oxygen sensitivity.

Main Methods:

• Development of a photoinduced initiators for continuous activator regeneration (PICAR) ATRP system.
• Utilized UV excitation and sodium pyruvate for continuous regeneration of the copper catalyst.
• Conducted polymerizations of N-isopropylacrylamide (NIPAM) and methyl acrylate (MA) in open reaction vessels.

Main Results:

• Achieved highly controlled polymerizations with quantitative monomer conversions (>99%) and high molecular weights (Mn > 270,000).
• Demonstrated low polymer dispersities (1.16 < Đ < 1.44) in under 30 minutes under biologically relevant conditions.
• Successfully performed well-controlled ATRP of MA in DMSO despite atmospheric oxygen diffusion.

Conclusions:

• The PICAR ATRP method provides a robust and practical solution for oxygen-tolerant polymerization.
• This technique broadens the applicability of ATRP in various solvents and open systems.
• The developed method offers efficient control over polymer synthesis under ambient conditions.