Photo-Mediated RAFT Step-Growth Polymerization With Diacrylate Monomers: Investigating Versatility and Oxygen...

Area of Science:

• Polymer Chemistry
• Photochemistry
• Organic Synthesis

Background:

• Reversible-Deactivation Radical Polymerization (RDRP) techniques enable precise control over polymer architecture.
• Photomediated polymerization offers spatial and temporal control over the reaction process.
• Step-growth polymerization is a crucial method for synthesizing high molecular weight polymers and complex architectures.

Purpose of the Study:

• To investigate the feasibility of photomediated reversible addition fragmentation chain transfer (RAFT) step-growth polymerization.
• To demonstrate the versatility of this method for synthesizing complex polymer structures, such as graft copolymers.
• To develop an oxygen-tolerant variant of photomediated RAFT step-growth polymerization for practical applications.

Main Methods:

• Utilizing a trithiocarbonate-based chain transfer agent (CTA) and acrylate monomers.
• Employing a photocatalyst to initiate and control the RAFT step-growth polymerization under visible light.
• Performing sequential monomer addition in a one-pot procedure to synthesize graft copolymers.
• Investigating the effect of photocatalyst and solvent choice (e.g., zinc tetraphenyl porphyrin [ZnTPP] and dimethyl sulfoxide [DMSO]) on oxygen tolerance.

Main Results:

• Successful execution of photomediated RAFT step-growth polymerization with acrylate monomers.
• Demonstration of one-pot synthesis of a graft copolymer through sequential monomer addition, showcasing versatility.
• Establishment of oxygen-tolerant conditions for photomediated RAFT step-growth polymerization using specific photocatalyst-solvent combinations.
• Achievement of ultralow volume polymerization under open-air conditions.

Conclusions:

• Photomediated RAFT step-growth polymerization is a versatile and controllable polymerization technique.
• The method allows for the efficient synthesis of complex polymer architectures like graft copolymers.
• The development of oxygen-tolerant conditions expands the practical applicability of this polymerization method, even under ambient conditions.