| abstract |
This invention relates to novel hydrogenation catalyst compositions obtainable from reacting metal-based complex hydrogenation catalysts, preferably (annellated) iminovinyloxy Ru species such as known by the trade names Umicore M41 or Umicore M42, with specific co-catalysts such as ethyl vinyl ether (EVE) and to a process for selectively hydrogenating nitrile rubbers in the presence of such novel hydrogenation catalyst compositions, optionally with prior metathetic decrease of molecular weight. |