A poly(-olefin) copolymer obtained from the polymerization of at least
one
-olefin having from 2 to about 20 carbon atoms and at least one bulky olefin,
the process comprising polymerizing the monomers in the presence of hydrogen and
a catalytically effective amount of a catalyst comprising the product obtained
by combining a metallocene procatalyst with a cocatalyst; lubricant compositions
comprising such poly(-olefin) copolymer; and a method for improving the
viscosity index of a lubricant composition using such poly(-olefin) copolymer.