Oxygen tolerant polymerizations including Photoinduced Electron/Energy Transfer-Reversible Addition–Fragmentation Chain-Transfer (PET-RAFT) polymerization allow for high-throughput synthesis of diverse polymer architectures on the benchtop in parallel. Recent developments have further increased throughput using liquid handling robotics to automate reagent handling and dispensing into well plates thus enabling the combinatorial synthesis of large polymer libraries. Although liquid handling robotics can enable automated polymer reagent dispensing in well plates, photoinitiation and reaction monitoring require automation to provide a platform that enables the reliable and robust synthesis of various polymer compositions in high-throughput where polymers with desired molecular weights and low dispersity are obtained. Here, we describe the development of a robotic platform to fully automate PET-RAFT polymerizations and provide individual control of reactions performed in well plates. On our platform, reagents are automatically dispensed in well plates, photoinitiated in individual wells with a custom-designed lightbox until the polymerizations are complete, and monitored online in real-time by tracking fluorescence intensities on a fluorescence plate reader, with well plate transfers between instruments occurring via a robotic arm. We found that this platform enabled robust parallel polymer synthesis of both acrylate and acrylamide homopolymers and copolymers, with high monomer conversions and low dispersity. The successful polymerizations obtained on this platform make it an efficient tool for combinatorial polymer chemistry. In addition, with the inclusion of machine learning protocols to help navigate the polymer space towards specific properties of interest, this robotic platform can ultimately become a self-driving lab that can dispense, synthesize, and monitor large polymer libraries.
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Reusable polymer brush-based photocatalysts for PET-RAFT polymerization
This contribution discusses the control over polymerizations using a heterogeneous photocatalyst based on fluorescein polymer brushes tethered to micron-scale glass supports (FPB@SiO 2 ). FPB@SiO 2 -catalyzed photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization is shown to provide high conversions, controlled molecular weights and narrow molecular weight distributions for a variety of monomers. Moreover, the beads can catalyze PET-RAFT on gram scales, in the presence of oxygen, while allowing full catalyst recovery through simple filtration. Finally, their high shelf-life allows for multiple polymerizations and user-friendly access to precision macromolecules under mild reaction conditions even after prolonged (months) storage time.
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- Award ID(s):
- 2143628
- NSF-PAR ID:
- 10394015
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 13
- Issue:
- 43
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 6120 to 6126
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2PY00966H
