FIELD: chemistry.
SUBSTANCE: invention relates to compositions of stereoselective Ziegler-Natta catalysts, intended for application in propylene polymerisation. Composition of catalyst of polymerisation of propylene or mixture of propylene and one or several copolymerised comonomers, including one or several compositions of Ziegler-Natta procatalysts, which include one or several transitive metal compounds and one or several internal electron donors in form of aromatic dicarboxyl acid esters; one or several aluminium-containing co-catalysts; and mixture of SCA reagents in form of two or more different selectivity regulators, said mixture of SCA reagents including from 1 to 99 molar per cent of one or several esters of one or several aromatic monocarbxylic acids or their substituted derivatives and from 99 to 1 molar per cent of one or more alkoxysilane compounds, said compounds and amounts being selected such that: 
where AT2(mixture) and AT1 (mixture) represent given catalyst activities with application of SCA reagents at temperatures T2 and T1 respectively; AT2(Si) and AT1(Si) represent given catalyst activities with application of only alkoxysilane SCA compound at temperatures T2 and T1 respectively; T1 represents usual polymerisation temperature in range from 50 to 85°C; and T2 represents polymerisation temperature exceeding T1, possibly occurring during polymerisation in non-standard conditions, ranging from 85 to 130°C. Polymerisation method includes bringing propylene or mixture of propylene and one or several copolymerised co-monomers under conditions of polymerisation carrying out at temperature ranging from 50 to 130°C into contact with said catalyst composition.
EFFECT: reduction or elimination of uncontrollable reaction acceleration, as well as softening or melting of polymer particles.
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