Cobalt-Chelated Polyamine Brushes on Solid Microspheres for Rapid Binding and Chemical Storage of Molecular Oxygen

Methylated poly­(vinyl amine) brushes generated on PS-DVB microspheres were demonstrated as excellent macroligands, forming hydrophilic Co­(II) chelates capable of reversible molecular oxygen binding. The oxygenation is extremely fast when counteranions of cobalt are replaced with hydroxyl ions. The experiments carried out using oxygen sensor, FT-IR, TGA techniques, and gas volumetric measurements showed that the polymer complexes with either 4/1 or 2/1 [amine]/[Co] ratios form 1:1 molecular oxygen adducts which are stable up to 110–120 °C. In order to impart the chain extension effect, poly­(vinyl amine-stat-DADMAC) brushes were also generated on the microspheres by using DADMAC as additional comonomer. Fast oxygenation, high oxygen binding capacity (ca. 80 mL/g), and long-term stability of the oxygen adducts make the polymeric complex superior to current systems. The cobalt complex system presented can be considered as a high capacity solid matrix for dissociation and chemical storage of the molecular oxygen from air