PROPYLENE-BASED BLOCK COPOLYMER, COMPOSITION CONTAINING SAID BLOCK COPOLYMER AND MOULDED ARTICLES OBTAINED THEREFROM Russian patent published in 2012 - IPC C08F297/08 C08F4/654 C08L23/14 C08J5/00 

FIELD: chemistry.

SUBSTANCE: block copolymer contains 5-80 wt % of a room temperature n-decane-soluble portion (Dsol) and 20-95 wt % of a room temperature n-decane-insoluble portion (Dinsol), under the condition that the total amount of the Dsol and the Dinsol is 100 wt % and satisfies the following requirements [1] to [3] at the same time: [1] the molecular weight distribution (Mw/Mn) of the Dsol is not less than 7.0 but not more than 30, [2] the molecular weight distribution (Mw/Mn) of the Dinsol is not less than 7.0 but not more than 30, and Mz/Mw thereof is not less than 6.0 but not more than 20, and [3] the pentad fraction (mmmm) of the Dinsol is not less than 93%. The Dsol contains, as a main component, a rubber copolymer containing propylene and one or more olefins selected from ethylene and α-olefins with 4-20 carbon atoms, and the Dinsol contains, as a main component, a crystalline propylene-based (co)polymer containing 98.5-100 mol % of propylene and 0-1.5 mol % of one or more olefins selected from ethylene and α-olefins with 4-20 carbon atoms.

EFFECT: high viscoelasticity of the melt, having an excellent balance between hardness and impact strength, good mouldability and ensures good outward appearance of articles moulded therefrom.

12 cl, 3 dwg, 6 tbl, 12 ex