A dinuclear gold( i ) complex as a novel photoredox catalyst for light-induced atom transfer radical polymerization

• Published in: Polymer chemistry Vol. 6; no. 25; pp. 4605 - 4611
• Main Authors: Nzulu, Frida, Telitel, Sofia, Stoffelbach, François, Graff, Bernadette, Morlet-Savary, Fabrice, Lalevée, Jacques, Fensterbank, Louis, Goddard, Jean-Philippe, Ollivier, Cyril
• Format: Journal Article
• Language: English
• Published: Royal Society of Chemistry - RSC 01.01.2015
• Subjects: Catalysts; Chemical Sciences; Conversion; Initiators; Laminates; Polymerization; Polymers; Polymethyl methacrylates; Radicals; Solubility
• ISSN: 1759-9954; 1759-9962
• DOI: 10.1039/C5PY00435G

Controlled/living atom transfer radical polymerization of methacrylates and acrylates initiated by ethyl α-bromophenylacetate (EBPA) as the initiator in the presence of low loadings (1.25 mol% vs . initiator) of a dinuclear gold( i ) complex based photocatalyst [Au 2 (μ-dppm) 2 ]Cl 2 has been accomplished in solution and in laminate under UVA and visible-light photoreductive conditions. In solution, the linear increase of molecular weights with methyl methacrylate (MMA) conversion and the low dispersity are consistent with a controlled/living process. In a film, trimethylolpropane triacrylate (TMPTA) was polymerized and the ethyl α-bromophenylacetate (EBPA)/[Au 2 (μ-dppm) 2 ]Cl 2 system resulted in a faster rate of polymerization compared to EBPA/Ir(ppy) 3 . Chain extensions of polymers were successfully conducted leading to block copolymers, which also confirms the living character of this new system. Photophysical experiments support a conventional photoredox-catalyzed ATRP mechanism. Finally, this approach utilizes a gold catalyst featuring better solubility and lower cost than the well-known Ir(ppy) 3 complex.