The present invention relates to a two-component supported catalyst, consisting of a) at least one transition metal compound applied on to an inorganic or polymeric organic supporting material, the metal being selected from the group of the d and f elements of the periodic table according to Mendeleev, b) at least one organometallic compound applied on to an inorganic or polymeric organic supporting material, the metal being selected from the group of the IIa, IIb and IIIb elements of the periodic table (F. A. Cotton, G. Wilkinson, Anorganische Chemie, 4th edition, VCH Verlagsgesellschaft mbH, Weinheim, 1985) and c) optionally at least one modifier which is supported on a) and/or on b), the transition metal compound in component a) being used in quantities of 0.1 to 100 mmol, based on 100 g of the supporting material, and the organometallic compound in component b) being used in quantities of 0.1 to 100 mmol, based on 100 g of the supporting material, and component c) being used in quantities of 0.01 to 500 mmol, based on 100 g of the supporting material, and the supporting materials of components a) to b) being used in quantitative ratios by weight (g/g) of 1.10−3 to 1000, and at least one of components a) or b) having a supporting material with an average particle size before or during polymerisation of