| abstract |
A compound useful as a cocatalyst or cocatalyst component, especially for use as an addition polymerization catalyst compound, corresponding to the formula: (A* +a ) b (Z*J* j ) −c d , wherein:n A* is a proton or a cation of from 1 to 80 atoms, preferably 1 to 60 atoms, not counting hydrogen atoms, said A* having a charge +a; Z* is an anion group of from 1 to 50 atoms, preferably 1 to 30 atoms, not counting hydrogen atoms, further containing two or more Lewis base sites, said Z* being the conjugate base of an inorganic Bronsted acid or a carbonyl- or non-cyclic, imino-group containing organic Bronsted acid; J* independently each occurrence is a Lewis acid of from 1 to 80 atoms, preferably 1 to 60 atoms, not counting hydrogen atoms, coordinated to at least one Lewis base site of Z*, and optionally two or more such J* groups may be joined together in a moiety having multiple Lewis acidic functionality; j is a number from 1 to 12; and a, b, c, and d are integers from 1 to 3, with the proviso that a×b is equal to c×d. |