FIELD: polymerization catalysts. SUBSTANCE: at least one olefin is brought into contact with catalytic system containing solid catalytic complex based on magnesium, transition metal, and halogen; organometallic compound with Ia, IIa, IIb, IIIa, and IVa group metals; and at least one electron donor which is used after the first step of solid catalytic complex preparation. The latter consists in reaction of one (at least in the first step) magnesium compound selected from organic oxygen-containing and halogen- containing magnesium compounds with at least one IVb or Vb group transition metal selected from organic oxygen-containing and halogen- containing transition metal compounds to form liquid complex, which is further precipitated as solid complex by agency of halogen-containing organoaluminum compound of general formula AlRnX3-n in which R is hydrocarbon radical, X halogen, and n is less than 3. EFFECT: improved mechanical and rheological properties of polymers. 16 cl
