Closed-Loop and Precision Synthesis of Polymuconates via Organocatalyzed Group Transfer Polymerization

Area of Science:

• Polymer Chemistry
• Organic Synthesis
• Sustainable Materials

Background:

• Group transfer polymerization (GTP) of conjugated dienes faces limitations.
• Developing metal-free polymerization methods is crucial for sustainability.
• Biobased polymers offer an alternative to petroleum-based plastics.

Purpose of the Study:

• To establish a controlled, metal-free polymerization platform for biobased polymuconates.
• To enable efficient closed-loop chemical recycling of these polymers.
• To overcome limitations in GTP of conjugated dienes.

Main Methods:

• Utilized a mild organocatalytic system (P2-t-Bu) in THF.
• Employed 1-ethoxy-1-(trimethylsiloxy)-1,3-butadiene (ETSB) as initiator.
• Investigated mechanistic pathways including 1,6-conjugate addition and dynamic exchange.

Main Results:

• Achieved rapid polymerization (<10 min, room temp) with excellent control over molar mass and dispersity (Đ ≤ 1.2).
• Demonstrated applicability to all three muconate ester stereoisomers, including biobased forms.
• Successfully synthesized block copolymers and confirmed living polymerization characteristics.

Conclusions:

• Developed a scalable, sustainable route to precision-engineered, degradable polar polydienes.
• Established a true closed-loop chemical recycling process for polymuconates.
• Presented a viable alternative to conventional vinyl polymers using biobased monomers.