An ionic catalyst system component comprising a water-stable anion having a plurality of lipophilic radicals covalently coordinated to and shielding a central, formal charge bearing metal or metalloid atom, in which the lipophilic radicals of the anion include substituted aromatic radicals useful for...http://www.google.com.au/patents/US5599761?utm_source=gb-gplus-sharePatent US5599761 - Ionic metallocene catalyst compositions
