The purpose of the present invention is to provide a propylene-based block copolymer, the deposition thereof on the inner wall of the polymerization vessel having been sufficiently inhibited. The propylene-based block copolymer of the present invention has a flowability evaluation value of 40% or less, the value being calculated with the following equation wherein X (sec) is the number of seconds over which 100 g of the copolymer having ordinary temperature falls from a stainless-steel funnel having an inner diameter of 11.9 mm and Y (sec) is the number of seconds over which 100 g of the copolymer which has been held at 80° C. for 24 hours under a load of 10 kg falls from the funnel having an inner diameter of 11.9 mm.
Flowability evaluation value (%)={(Y/X)−1}×100.

The present disclosure discloses an arylaminosilane compound, a propylene polymerization catalyst and preparation thereof. The arylaminosilane compound has a structure of ##STR00001##
wherein R.sub.1 is a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 silanyl group; R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently H or a C.sub.1-C.sub.12 alkyl group; R.sub.7, R.sub.8 and R.sub.9 are each independently a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 alkoxy group. When the arylaminosilane compound is used as an external electron donor of a propylene polymerization catalyst in propylene polymerization reaction, the catalyst has good hydrogen response.

The present disclosure discloses an arylaminosilane compound, a propylene polymerization catalyst and preparation thereof. The arylaminosilane compound has a structure of ##STR00001##
wherein R.sub.1 is a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 silanyl group; R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently H or a C.sub.1-C.sub.12 alkyl group; R.sub.7, R.sub.8 and R.sub.9 are each independently a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 alkoxy group. When the arylaminosilane compound is used as an external electron donor of a propylene polymerization catalyst in propylene polymerization reaction, the catalyst has good hydrogen response.

A process for preparing a catalyst component made from or containing Mg, Ti, and at least an electron donor compound (ID), including the steps of: (a) reacting a Mg based compound with a Ti compound, having at least a Ti—Cl bond, in an amount such that the Ti/Mg molar ratio is greater than 3 and at a temperature ranging from 0 to 150° C., thereby yielding an intermediate solid catalyst component containing Mg and Ti; and (b) contacting the intermediate solid catalyst component with a gaseous stream containing the electron donor compound (ID) in a gaseous dispersing medium, thereby yielding a final solid catalyst component having an ID/Ti molar ratio ranging from 0.5:1 to 20:1.

A process for preparing a catalyst component made from or containing Mg, Ti, and at least an electron donor compound (ID), including the steps of: (a) reacting a Mg based compound with a Ti compound, having at least a Ti—Cl bond, in an amount such that the Ti/Mg molar ratio is greater than 3 and at a temperature ranging from 0 to 150° C., thereby yielding an intermediate solid catalyst component containing Mg and Ti; and (b) contacting the intermediate solid catalyst component with a gaseous stream containing the electron donor compound (ID) in a gaseous dispersing medium, thereby yielding a final solid catalyst component having an ID/Ti molar ratio ranging from 0.5:1 to 20:1.

A Ziegler-Natta catalyst composition is disclosed. The catalyst composition includes an internal electron donor with improved polymerization kinetics, a long lifetime, improved stereoselectivity and/or improved hydrogen response.

A Ziegler-Natta catalyst composition is disclosed. The catalyst composition includes an internal electron donor with improved polymerization kinetics, a long lifetime, improved stereoselectivity and/or improved hydrogen response.

Provided is a solid catalyst component for olefin polymerization which is capable of exerting favorable ethylene responsiveness while forming a propylene homopolymer having high stereoregularity, when subjected to ethylene-propylene copolymerization reaction. The present invention provides a solid catalyst component for olefin polymerization, comprising titanium, magnesium, halogen, and an internal electron-donating compound, wherein the internal electron-donating compound comprises an electron-donating compound (i) having a phthalic acid ester structure, and an electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure, wherein a content ratio of the electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure is 0.5 to 1.5% by mass.

Provided is a solid catalyst component for olefin polymerization which is capable of exerting favorable ethylene responsiveness while forming a propylene homopolymer having high stereoregularity, when subjected to ethylene-propylene copolymerization reaction. The present invention provides a solid catalyst component for olefin polymerization, comprising titanium, magnesium, halogen, and an internal electron-donating compound, wherein the internal electron-donating compound comprises an electron-donating compound (i) having a phthalic acid ester structure, and an electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure, wherein a content ratio of the electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure is 0.5 to 1.5% by mass.

A polymerization process includes contacting an olefin or a mixture of the olefin and one or more copolymerizable comonomers under polymerization conditions with a catalyst composition and forming a polymer with a total ash content of less than 15 ppm. The catalyst composition includes one or more polymerization catalysts; and a mixed external electron donor comprising a selectivity control agent comprising at least one silicon-containing compound containing at least one C1-C10 alkoxy group bonded to a silicon atom.