The present invention relates to a supported catalyst system for olefin polymerization
which comprises at least one metallocene component and a support of an inorganic
oxide of silica, aluminum or a polymer containing hydroxyl groups. The support
is modified with an organogermane and/or organotin compound. The inventive catalyst
system produces minimal reactor fouling, has excellent productivity and good hydrogen
responsiveness. The present invention also relates to a process for preparing the
catalyst system and to the slurry/suspension or gas-phase polymerization of olefins
using the catalytic system, optionally with a small amount of aluminoxane cocatalyst.
