| abstract |
FIELD: chemistry. n SUBSTANCE: invention relates to means of controlling selectivity in polymerization of olefins. Disclosed is an external electron donor composition for olefin polymerization, comprising a monoester as an activity limiting agent together with alkoxysilane as a selectivity control means, wherein mol percentage ratio of alkoxysilane to monoester is 50:50, alkoxysilane is selected from dialkoxysilanes and trialkoxysilanes and mixture thereof, and the monoester is selected from diphenyl ether, dibutyl ether, dibenzyl ether and butyl phenyl ether. Disclosed also is a method of polymerization of olefins, in which the catalyst system contains said external electron-donating composition. n EFFECT: obtaining olefins with required characteristics without contamination of the reactor with prolonged preservation of catalyst activity. n 3 cl, 5 tbl |