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Abstract Alternating current (AC) and pulsed electrolysis are gaining traction in electro(organic) synthesis due to their advantageous characteristics. We employed AC electrolysis in electrochemically mediated Atom Transfer Radical Polymerization (eATRP) to facilitate the regeneration of the activator CuIcomplex on Cu0electrodes. Additionally, Cu0served as a slow supplemental activator and reducing agent (SARA ATRP), enabling the activation of alkyl halides and the regeneration of the CuIactivator through a comproportionation reaction. We harnessed the distinct properties of Cu0dual regeneration, both chemical and electrochemical, by employing sinusoidal, triangular, and square‐wave AC electrolysis alongside some of the most active ATRP catalysts available. Compared to linear waveform (DC electrolysis) or SARA ATRP (without electrolysis), pulsed and AC electrolysis facilitated slightly faster and more controlled polymerizations of acrylates. The same AC electrolysis conditions could successfully polymerize eleven different monomers across different mediums, from water to bulk. Moreover, it proved effective across a spectrum of catalyst activity, from low‐activity Cu/2,2‐bipyridine to highly active Cu complexes with substituted tripodal amine ligands. Chain extension experiments confirmed the high chain‐end fidelity of the produced polymers, yielding functional and high molecular‐weight block copolymers. SEM analysis indicated the robustness of the Cu0electrodes, sustaining at least 15 consecutive polymerizations.
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Cu‐Catalyzed Atom Transfer Radical Polymerization: The Effect of Cocatalysts
Abstract Atom transfer radical polymerization (ATRP) is one of the most powerful methods to prepare well‐defined (co)polymers. Cu‐catalyzed ATRP methods are most commonly used because of the excellent control and tunable catalytic activities via ligand functionalization. This minireview summarizes the development of Cu‐catalyzed ATRP in the presence of cocatalysts, which are used to regenerate CuIcomplex activators during polymerizations. Fundamentals of Cu‐based ATRP catalysts are first introduced, followed by the discussion of different types of cocatalysts in different Cu‐catalyzed ATRP methods. Recent developments of photochemical cocatalysts for oxygen‐tolerant ATRP and ATRP using long‐wavelength irradiation are highlighted, which significantly expand the applications of Cu‐catalyzed ATRP. Methods to study the properties of cocatalysts and their roles in Cu‐catalyzed ATRP are discussed, with an outlook for the future development of cocatalysts.
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- Award ID(s):
- 2000391
- PAR ID:
- 10383244
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 224
- Issue:
- 3
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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