A Simplified Fe-Based PhotoATRP Using Only Monomers and Solvent.

Area of Science:

• Polymer Chemistry
• Organic Synthesis
• Photochemistry

Background:

• Atom Transfer Radical Polymerization (ATRP) is a controlled polymerization technique.
• Conventional ATRP often requires specific initiators, ligands, and reducing agents.
• Developing simpler and more efficient ATRP methods is an ongoing research goal.

Purpose of the Study:

• To investigate a photoinduced ATRP (photoATRP) of methacrylates using a simplified catalytic system.
• To explore the use of air-stable FeBr3 as a catalyst without conventional ATRP additives.
• To demonstrate the in situ formation of ATRP initiators and control over polymerization.

Main Methods:

• Photoinduced atom transfer radical polymerization (photoATRP) of methacrylates.
• Utilized air-stable FeBr3 as the sole catalyst.
• Investigated polymerization kinetics and molecular weight control.
• Analyzed polymer chain end functionality.

Main Results:

• Successful photoATRP of methacrylates was achieved using FeBr3.
• ATRP initiator formed in situ via photoreduction of FeBr3 by monomers.
• Polymerization kinetics showed a linear semilogarithmic plot after an induction period.
• Achieved control over molecular weight and narrow molecular weight distributions.
• FeBr3 functioned as a deactivator, activator source (FeBr2), and initiator.

Conclusions:

• Developed a novel, initiator-free photoATRP method for polymethacrylates.
• Demonstrated temporal control and high chain end functionality in synthesized polymers.
• This FeBr3-catalyzed system offers a simplified and efficient approach to controlled polymerization.