This chapter highlights the current advancements in reversible-deactivation radical polymerization (RDRP) with a specific focus on atom transfer radical polymerization (ATRP). The chapter begins with highlighting the termination pathways for acrylates radicals that were recently explored via RDRP techniques. This led to a better understanding of the catalytic radical termination (CRT) in ATRP for acrylate radicals. The designed new ligands for ATRP also enabled the suppression of CRT and increased chain end functionality. In addition, further mechanistic understandings of SARA-ATRP with Cu0 activation and comproportionation were studied using model reactions with different ligands and alkyl halide initiators. Another focus of RDRP in recent years has been on systems that are regulated by external stimuli such as light, electricity, mechanical forces and chemical redox reactions. Recent advancements made in RDRP in the field of complex polymeric architectures, organic-inorganic hybrid materials and bioconjugates have also been summarized.
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Catalyzed Radical Termination (CRT) in the Metal-Mediated Polymerization of Acrylates: Experimental and Computational Studies
Metal complexes stabilized by appropriate ligands, particularly CuI/L systems, have proven powerful for the controlled polymerization of acrylates and other monomers by atom transfer radical polymerization (ATRP). The polymerization of acrylates by CuI/L systems, however, is haunted by interference of catalyzed radical termination (CRT), which reduces the chain-end fidelity. Other monomers do not appear to be affected by this phenomenon to any significant extent. The phenomenon appears to involve the formation of an organometallic intermediate by reversible radical trapping, as in organometallic mediated radical polymerization (OMRP). We summarize here the current knowledge and the efforts made to elucidate the CRT pathway and products.
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- Award ID(s):
- 1707490
- PAR ID:
- 10184891
- Date Published:
- Journal Name:
- ACS symposium series
- ISSN:
- 0097-6156
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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