Efficient polymerization of acrylonitrile catalyzed by divalent lanthanidecomplex/sodium phenolate systems

Four divalent lanthanide complexes Sm(ArO)(2) (THF)(4), Yb(ArO)(2)(THF)(3), Eu(ArO)(2)(THF)(3) (ArO = 2,6-ditert-butyl-4-methylphenolate) and ((BuCP)- C-t)(2)Sm(THF)(2) were synthesized. Their catalytic activities on the polym erization of acrylonitrile were studied. The catalytic activities were infl uenced by the central metal ions involved. The catalytic activities of thes e divalent lanthanide complexes can be greatly increased by adding NaOC6H2- 2,6-Bu-2(t)-4-Me, NaOC6H4-4-Bu-t, or NaOC10H6-2-Me. The amount of additive has apparent effect on the catalytic activity, but the additive has no effe ct on the tacticity of the resulting polyacrylonitrile.