Photo‐induced organo‐manganese‐mediated radical polymerization of acrylates under LED irradiation

• DOI: 10.1002/aoc.7495
• Publication Date: 2024-04-29T00:24:25Z
• Authors: Naralyne M. Pesqu...; Kathia H. Lira; Camila Bignardi; Milene K. C. da S...; Thiago F. Silva; Antonio E. H. Mac...; Otaciro R. Nascim...; Valdemiro P. Carv...; Beatriz E. Goi
• Keywords: Molar conductivity

The role of manganese in photo‐induced organometallic‐mediated radical polymerization (photo‐OMRP) under LED (light‐emitting diode) irradiation has not been previously explored. In this study, four (II) complexes, namely [Mn(6‐ tert ‐butyl‐N,N′‐propanebis [salicylimine])] ( Mn‐Bu ), [Mn(6,3‐di‐ 2 [Mn(6‐ethoxy‐N,N′‐propanebis Mn‐Ethoxy and [Mn(6,3‐di‐ethoxy ‐ N,N′‐propanebis were synthesized using both symmetrical non‐symmetrical tetradentate N O Schiff base ligands. ligands characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–Vis), nuclear magnetic resonance (NMR). Mn complexes FTIR, UV–Vis, elemental analysis, molar conductivity, cyclic voltammetry, MALDI‐TOF mass spectrometry, electron paramagnetic resonance, rationalized with density functional theory (DFT) studies. All evaluated as photo‐OMRP mediators at 390 nm the 400–800 range. photopolymerization utilized methyl acrylate (MA) diphenyl(2,4,6‐trimethylbenzoyl)phosphine oxide (TPO) varying ratios [MA]/[Mn II ]/[TPO] (900/1/1, 600/1/1, 600/1/0.5). MA mediated showed best control over molecular weight (M n matching M n,th ) dispersity (Ð < 1.30) a = 600/1/0.5 ratio. system demonstrated living character, evidenced reversible “on/off” light source switching. Furthermore, block copolymer poly (methyl acrylate)‐ b ‐poly (butyl acrylate) was successfully employing sequential visible‐light‐induced process, showing results.