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Abstract The sustainable synthesis of macromolecules with control over sequence and molar mass remains a challenge in polymer chemistry. By coupling mechanochemistry and electron‐transfer processes (i.e., mechanoredox catalysis), an energy‐conscious controlled radical polymerization methodology is realized. This work explores an efficient mechanoredox reversible addition‐fragmentation chain transfer (RAFT) polymerization process using mechanical stimuli by implementing piezoelectric barium titanate and a diaryliodonium initiator with minimal solvent usage. This mechanoredox RAFT process demonstrates exquisite control over poly(meth)acrylate dispersity and chain length while also showcasing an alternative to the solution‐state synthesis of semifluorinated polymers that typically utilize exotic solvents and/or reagents. This chemistry will find utility in the sustainable development of materials across the energy, biomedical, and engineering communities.
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Macromolecules with programmable shape, size, and chemistry
Shape, size, and composition are the most fundamental design features, enabling highly complex functionalities. Despite recent advances, the independent control of shape, size, and chemistry of macromolecules remains a synthetic challenge. We report a scalable methodology to produce large, well-defined macromolecules with programmable shape, size, and chemistry that combines reactor engineering principles and controlled polymerizations. Specifically, bottlebrush polymers with conical, ellipsoidal, and concave architectures are synthesized using two orthogonal polymerizations. The chemical versatility is highlighted by the synthesis of a compositional asymmetric cone. The strong agreement between predictions and experiments validates the precision that this methodology offers.
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- Award ID(s):
- 1727605
- PAR ID:
- 10083511
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 116
- Issue:
- 5
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 1538-1542
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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