Ultrafast Thermal RAFT Depolymerization at Higher Solid Contents

Area of Science:

• Polymer Chemistry
• Chemical Recycling
• Sustainable Materials

Background:

• Thermal reversible-deactivation radical polymerization (RAFT) depolymerization is an emerging chemical recycling method.
• Current RAFT depolymerization methods are limited by specialized solvents, long reaction times, and dilute conditions.

Purpose of the Study:

• To overcome limitations of existing thermal RAFT depolymerization techniques.
• To enhance the efficiency and applicability of polymer chemical recycling.

Main Methods:

• Introduction of a commercial radical initiator to kinetically untrap depolymerization.
• Optimization of initiator concentration for rate acceleration.
• Testing depolymerization yields across various solvents and higher concentrations.

Main Results:

• A 72-fold rate acceleration was achieved by optimizing initiator concentration, completing depolymerization in 5 minutes.
• High depolymerization yields were maintained with a 20-fold increase in repeat unit concentration.
• Successful monomer recovery was demonstrated in diverse solvents like DMSO, anisole, and toluene.

Conclusions:

• Radical initiators significantly enhance thermal RAFT depolymerization rates and efficiency.
• This optimized method broadens the scope of RAFT depolymerization for practical polymer recycling.
• The findings provide mechanistic insights and expand applications for sustainable polymer chemistry.