abstract |
The present invention relates to a catalyst for polymerizationnof a conjugated diene or the like, which is composed of anmetallocene-type cation complex of a gadolinium compound. Examplesnof such catalyst include a metallocene-type cation complex of antrivalent gadolinium compound represented by the general formulan(I): R a GdX b (wherein, Gd represents gadolinium; R represents ancyclopentadienyl group, a substituted cyclopentadienyl group, annindenyl group, a substituted indenyl group, a fluorenyl group, orna substituted fluorenyl group; X represents an anion; "a" representsnan integer of 1 or 2; and "b" represents an integer of 1 or 2).nThe present invention provides a catalyst by which polymerizationnof a conjugated diene or copolymerization of a conjugated dienenand an aromatic vinyl compound can be carried out efficiently andninexpensively. |