Supported catalyst systems, processes for their preparation, and methods for preparing poly-1-alkenes having a bimodal or multimodal molecular mass distribution

The invention relates to supported catalyst systems that contain A) inorganic or organic carrier particles with an average particle diameter in the range of from 1 to 1000 mu m, B) at least two metallocene complexes, and C) at least one metal compound of the general formula (II) M (R )r(R )s(R )t(R )u wherein M represents an alkali metal or alkaline earth metal or a metal of main group III or IV of the periodic system, R is hydrogen, C1-C10 alkyl, C6-C15 aryl, alkylaryl or arylalkyl with 1 to 10 C atoms each in the alkyl group and 6 to 20 C atoms in the aryl group, R to R represent hydrogen, halogen, C1-C10 alkyl, C6-C15 aryl, alkylaryl, arylalkyl, alkoxy or dialkylamino with 1 to 10 C atoms each in the alkyl group and 6 to 20 C atoms in the aryl group, r is an integer of 1 to 4, and s, t and u are integers from 0 to 3, the sum r+s+t+u corresponding to the valence of M , and with only one metallocene complex each being applied on the individual carrier particles.