The present disclosure provides a catalyst system made from or containing: (A) a solid catalyst component made from or containing (i) a titanium compound supported on a magnesium dichloride; (B) an aluminum alkyl compound; and (C) a halogenated organic ester of formula A-COOR, wherein R is a C.sub.1-C.sub.10 hydrocarbon group and A is a C.sub.1-C.sub.15 saturated or unsaturated hydrocarbon group in which at least one of the hydrogen atoms is replaced by a chlorine atom. The present disclosure also provides a process for preparing an olefinic polymer, including a polymerization step of polymerizing an olefin in the presence of the catalyst system. The present disclosure also provides an olefinic polymer made therefrom.

Catalyst systems for polymerization of mixtures comprising an olefin include a selectivity control agent comprising at least one silicon-containing compound containing at least one C1-C10 alkoxy group bonded to a silicon atom and an amount of one or more agent compounds. The agent compound comprises C2-C13 mono- or polycarboxylic esters of aliphatic C2-C7 carboxylic acids and inertly substituted derivatives thereof. One or more polymerization catalysts may also be present. A polymerization process includes contacting an olefin or a mixture of the olefin and one or more copolymerizable comonomers under polymerization conditions with the catalyst composition.

Catalyst systems for polymerization of mixtures comprising an olefin include a selectivity control agent comprising at least one silicon-containing compound containing at least one C1-C10 alkoxy group bonded to a silicon atom and an amount of one or more agent compounds. The agent compound comprises C2-C13 mono- or polycarboxylic esters of aliphatic C2-C7 carboxylic acids and inertly substituted derivatives thereof. One or more polymerization catalysts may also be present. A polymerization process includes contacting an olefin or a mixture of the olefin and one or more copolymerizable comonomers under polymerization conditions with the catalyst composition.

Provided is a solid catalyst component for olefin polymerization comprising an electron-donating compound other than a phthalate, the solid catalyst component being equal in the olefin-polymerizing activity and in the primary physical properties of the resulting polymer such as stereoregularity and molecular weight distribution to those with use of a phthalate as an electron-donating compound. A solid catalyst component for olefin polymerization comprises a magnesium atom, a titanium atom, a halogen atom, an ester compound (A) represented by a general formula (1) and a diester compound (B) represented by a general formula (2), wherein a ratio represented by the following expression:
(content (mass %) of ester compound (A)/content (mass %) of diester compound (B))
is 0.05 to 50.

Disclosed are a Z-N catalyst for α-olefin polymerization and an application thereof, specifically, an industrial production catalyst consisting of (A) a solid catalyst component, (B) a cocatalyst organoaluminum compound and (C) an external electron donor compound and used for α-olefin polymerization or copolymerization processes. The catalyst component is prepared from a transition metal such as titanium and magnesium and a composite aromatic diacid diester/1,3-diether as an internal electron donor. One or more organoaluminum compounds or a mixture thereof serve as the cocatalyst. One or more structure control agent hydrocarbyl alkoxysilicons are compounded with one or more activity regulator organic acid esters as the external electron donor capable of automatically adjusting the polymerization rate. The Z-N catalyst is used for α-olefin polymerization/copolymerization, and can automatically adjust the polymerization rate at a higher polymerization temperature so as to maintain stable operation of a reactor.

Disclosed are a Z-N catalyst for α-olefin polymerization and an application thereof, specifically, an industrial production catalyst consisting of (A) a solid catalyst component, (B) a cocatalyst organoaluminum compound and (C) an external electron donor compound and used for α-olefin polymerization or copolymerization processes. The catalyst component is prepared from a transition metal such as titanium and magnesium and a composite aromatic diacid diester/1,3-diether as an internal electron donor. One or more organoaluminum compounds or a mixture thereof serve as the cocatalyst. One or more structure control agent hydrocarbyl alkoxysilicons are compounded with one or more activity regulator organic acid esters as the external electron donor capable of automatically adjusting the polymerization rate. The Z-N catalyst is used for α-olefin polymerization/copolymerization, and can automatically adjust the polymerization rate at a higher polymerization temperature so as to maintain stable operation of a reactor.

Disclosed are catalyst compositions having an internal electron donor which includes a 3,6-di-substituted-1,2-phenylene aromatic diester. Ziegler-Natta catalyst compositions containing the present catalyst compositions exhibit very high hydrogen response, high activity, high selectivity and produce propylene-based olefins with high melt flow rate.

Disclosed are catalyst compositions having an internal electron donor which includes a 3,6-di-substituted-1,2-phenylene aromatic diester. Ziegler-Natta catalyst compositions containing the present catalyst compositions exhibit very high hydrogen response, high activity, high selectivity and produce propylene-based olefins with high melt flow rate.

An activated solid catalyst component is disclosed formed from a magnesium compound, a titanium compound, an organosilicon compound, a supportive electron donor, and at least one internal electron donor. The solid catalyst component is activated to include titanium and carbon bonds by reaction with an activation agent, such as an aluminum compound. In one embodiment, small amounts of polymer are polymerized with the catalyst component during activation. The activated catalyst component is stable and, when formed, can later be used to produce various polyolefin polymers. The activated catalyst component has controlled reaction kinetics so that the catalyst does not overheat and degrade during initial polymerization.

An activated solid catalyst component is disclosed formed from a magnesium compound, a titanium compound, an organosilicon compound, a supportive electron donor, and at least one internal electron donor. The solid catalyst component is activated to include titanium and carbon bonds by reaction with an activation agent, such as an aluminum compound. In one embodiment, small amounts of polymer are polymerized with the catalyst component during activation. The activated catalyst component is stable and, when formed, can later be used to produce various polyolefin polymers. The activated catalyst component has controlled reaction kinetics so that the catalyst does not overheat and degrade during initial polymerization.