| 초록 |
The effects of B(C6F5)3 on the activation of the Ni(0) and Ni(II) complexes were studied in the polymerization of norbornene. The Ni(0) complex, such as bis(1,5-cyclooctadiene)nickel (Ni(COD)2 (1), in combination with B(C6F5)3, was determined to have high activity in the polymerization of norbornene even in the absence of MAO or AlEt3. On the other hand, the Ni(II) complexes, such as Ni(2-ethyl hexanoate)2 (2), [1,2-bis(diphenylphophino)ethane]dichloronickel(II) (3), nickel(II) bromide ethylene glycol dimethyl ether complex (4), N,N’-bis(salicylidene)ethylenediamino nickel(II) (5), and Ni(acetate)2 (6), with B(C6F5)3 did not provide any activity at all under analogous conditions regardless of the structure of the Ni(II) complexes. The concurrent employment of Ni(II)/B(C6F5)3 and MAO, however, dramatically induced polymerization, showing that MAO was an essential ingredient for activity when using Ni(II) complex. |
