Patent ID: 7321017

Claim:
A catalyst system comprising: an organolithium compound; a group IIa metal salt; an organoaluminum compound; and an amine compound selected from the group consisting of a heterocyclic aromatic compound defined by a substituted or unsubstituted 3-, 4-, or 5-membered ring structure with at least one nitrogen atom as part of the ring, an unsubstituted 6-membered ring structure with one nitrogen atom as part of the ring, a substituted or unsubstituted 6-membered ring structure with at least two nitrogen atoms as part of the ring, quinoline, 2-picoline, 3-picoline, or 4-picoline; a heterocyclic non-aromatic compound defined by a substituted or unsubstituted 3-, 4-, 5-membered ring structure with at least two nitrogen atoms as part of the ring, an unsubstituted 6-membered ring structure with at least two nitrogen atoms as part of the ring, or N,N-dimethyl piperazine, and N-methyl piperazine; an aromatic compound including a ring structure substituted with at least one amine and at least one polar functionality containing group; a bicyclic chelating diamine compound; and an aliphatic amine which includes a C 8 -C 20 alkyl group.