Patent ID: 7608664

Claim:
A process for forming a polymer useful in a curable sealant composition comprising: a. initiating a living polymerization of conjugated diene monomers with a multi-functional initiator, b. terminating said polymerization with a tetra-substituted silicon compound of formula to produce a functionalized polymer, where R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrocarbon groups, alkoxy groups and mixtures thereof, and no more than two of R 1 , R 2 , R 3 , and R 4 may be hydrocarbon groups, and at least two of R 1 , R 2 , R 3 , and R 4 are alkoxy groups, and c. hydrogenating the functionalized polymer in the presence of a catalyst system comprising a nickel carboxylate and alkylaluminum, wherein said catalyst system has a Al:Ni ratio between about 3.0 and about 4.0.