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Abstract The photoATRP of methyl acrylate (MA) is investigated using riboflavin (RF) and CuBr₂/Me₆TREN as a dual catalyst system under green LED irradiation (λ ≈ 525 nm). Both RF and CuBr₂/Me₆TREN enhanced oxygen tolerance, enabling effective ATRP in the presence of residual oxygen. High molar mass polymers (up toM_n ≈ 129 000 g·mol⁻¹) with low dispersity (Đ≤ 1.16) are prepared, and chain‐end fidelity is confirmed through successful chain extension. The molecular masses of the obtained polymer increased linearly with conversion and showed high initiation efficiency. Mechanistic studies by laser flash photolysis reveal that the predominant activator generation mechanism is reductive quenching of RF by Me₆TREN (83%, under [CuBr₂]/[Me₆TREN] = 1/3 condition), supported by polymerization kinetics and thermodynamic calculations. 

Abstract Photomediated Atom Transfer Radical Polymerization (photoATRP) is an activator regeneration method, which allows for the controlled synthesis of well‐defined polymers via light irradiation. Traditional photoATRP is often limited by the need for high‐energy ultraviolet or violet light. These could negatively affect the control and selectivity of the polymerization, promote side reactions, and may not be applicable to biologically relevant systems. This drawback can be circumvented by an introduction of the catalytic amount of photocatalysts, which absorb visible and/or NIR light and, therefore, controlled, regenerative ATRP can be performed with the dual‐catalytic cycle. Herein, a critical summary of recent developments in the field of dual‐catalysis concerning Cu‐catalyzed ATRP is provided. Contributions of involved species are examined mechanistically, followed by challenges and future directions towards the next generation of advanced functional macromolecular materials. 

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 Cu^Icomplex 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 Cu^Iactivator 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. 

A photoinduced reversible addition-fragmentation chain-transfer (photo-RAFT) polymerization technique in the presence of sodium pyruvate (SP) and pyruvic acid derivatives was developed.