The catalytic activity of Ni-Al(i-Bu)

OR-B and Ni-Al(i-Bu)2 OAr-B system (-OR is -OC8H17

-OC9H19 and -OAr is -O-Ph-CH3

-O-Ph-C8H17) for the polymerization of butadiene in hydrogenated dasoline

the modecular weight of the polymer

and the micros tructure of the polymer have been studied. The result showed that the catalytic activity of the new nickel catalpst system for the polymerization of butadiene is very high when the co-cata-lyst is Al(i-Bu)2OR or Al(i-Bu)2OAr

and that the content of Cis-1

4 unit in polymer pre-pared is about 96%. Based on the mapnetic susceptibility measurement and OW-VIS spectum of the new nickel catalst systems

it could be seen that the Ni(I) existe mainly in the Al(i-Bu)2OR system

and te Ni(I)and Ni(O) coexisted in the Al(i-Bu)2 OAr system.