Regensburg 2019 – wissenschaftliches Programm
CPP 25.24: Poster
Dienstag, 2. April 2019, 14:00–16:00, Poster B1
Metallo-polymers and -gels based on photosensitive ruthenium(II) complexes and polyethylene glycol — •Leonhard Buchriegler1, Sabrina Theis2, Ian Teasdale3, Sabine Hild1, and Uwe Monkowius4 — 1Institute of Polymer Science, Johannes Kepler University Linz, Austria — 2Institute of Inorganic Chemistry, Johannes Kepler University Linz, Austria — 3Institute of Polymer Chemistry, Johannes Kepler University Linz, Austria — 4Linz School of Education, Johannes Kepler University Linz, Austria
The interest in photo-cleavable polymers has increased significantly due to their broad range of potential applications. The complex [Ru(II)(bpy)2(4-AMP)2]2+ (bpy = 2,2‘-bipyridine, 4-AMP = 4-(aminomethyl)pyridine) can be used to generate light-sensitive polyurea supramolecular organogels. This complex has a high photo-cleavage quantum yield and high storage stability in solution in the dark as well as in neat form. In this contribution, we present a light-sensitive organogel which is composed of the Ru-complex and an 8-arm polyethylene glycol (PEG). The gel is prepared via reaction between amine functions of the Ru-complex and the terminal modified polyethylene glycol forming a crosslinked polyurethane with both 4-(aminomethyl)pyridine ligands connecting two PEG-arms. Irreversible de-gelation occurs within minutes upon irradiation with visible light (λ > 395 nm), i.e. the Ru-bound pyridine is replaced by a solvent molecule, here acetonitrile. The synthesis and photocleavage-process were investigated by 1H-NMR spectroscopy, mass spectrometry and UV/Vis-spectroscopy.