FIELD: chemistry.
SUBSTANCE: present invention relates to polyolefin catalyst systems, more specifically to internal or external electron donors. Described is a solid component of a precatalyst for use in polymerization of olefins, which includes titanium, magnesium and a compound which is an electron donor. Electron donor compound contains at least one compound of formula (I), where E is silicon (Si) or germanium (Ge), provided that when E is Si, two or more of R1, R2, R3 and R4 form a cycle to form a hydrocarbyl ring structure, optionally interrupted or substituted with an ester functional group. Catalyst system and polymerization method are also described.
(I).
EFFECT: use of catalytic systems containing a solid component of a precatalyst provides catalysts with high catalytic efficiency and one or more of excellent melt flow, extrudability, moldability, balance of stiffness and elasticity and impact strength.
19 cl, 2 dwg, 5 tbl, 3 ex
