In situ bidentate to tetradentate ligand exchange reaction in cobalt-mediated radical polymerization

Réaction d'échange in situ de ligand bidenté pour ligand tétradenté en polymérisation radicalaire contrôlée par le cobalt

Anthony Kermagoret (1, 2) , Christine Jérôme (2) , Christophe Detrembleur (2) , Antoine Debuigne (2)

1 ICR - Institut de Chimie Radicalaire
2 CERM - Centre d'Etude et de Recherche sur les Macromolécules

Organometallic-mediated radical polymerization (OMRP) has seen a significant growth in the last years notably due to the development of new metal complexes, especially cobalt derivatives. Despite of this, none of the reported complexes offers optimal control for monomers with very different reactivity, which somewhat limits the synthesis of copolymers. In order to expand the scope of cobalt-mediated radical polymerization (CMRP), we investigated an in situ ligand exchange reaction for modulating the properties of the cobalt complex at the polymer chain-end and adjusting the C-Co bond strength involved in the control process. With the aim of improving the synthesis of poly(vinyl acetate)-b-poly(nbutyl acrylate) copolymers, bidentate acetylacetonate ligands, which impart high level of control to the polymerization of vinyl acetate (VAc), were replaced in situ at the PVAc-cobalt chain-end by tetradentate Salen type ligands that are more suited to acrylates.

Mots clés: cobalt complexes; Salen ligand; acrylate; block copolymers; organometallic-mediated radical polymerization (OMRP); cobaltmediated radical polymerization (CMRP); vinyl acetate

Domaines: Polymères

Anthony Kermagoret, Christine Jérôme, Christophe Detrembleur, Antoine Debuigne. In situ bidentate to tetradentate ligand exchange reaction in cobalt-mediated radical polymerization. European Polymer Journal, 2014, 62, pp.312-321. ⟨10.1016/j.eurpolymj.2014.08.003⟩. ⟨hal-01344604⟩