The present disclosure relates to a Ziegler-Natta catalyst system with self-extinguishing properties suitable for olefin polymerization. The catalyst system of the present disclosure comprises a pro-catalyst, a co-catalyst, and an external donor having a mixture of a selectivity control agent and an activity control agent. The catalyst system of the present disclosure is adapted to prevent the temperature of the polymerization reaction to go beyond the softening temperature of the polymer, thereby exhibiting the self-extinguishing properties.

The present disclosure relates to a Ziegler-Natta catalyst system with self-extinguishing properties suitable for olefin polymerization. The catalyst system of the present disclosure comprises a pro-catalyst, a co-catalyst, and an external donor having a mixture of a selectivity control agent and an activity control agent. The catalyst system of the present disclosure is adapted to prevent the temperature of the polymerization reaction to go beyond the softening temperature of the polymer, thereby exhibiting the self-extinguishing properties.

The present disclosure provides a gas-phase polymerization process for preparing polyethylene, wherein halogenated alcohols in combination with a Ti based catalyst component and aluminum alkyls as co-catalyst suppress ethane formation or increase polymerization activity.

The present disclosure provides a gas-phase polymerization process for preparing polyethylene, wherein halogenated alcohols in combination with a Ti based catalyst component and aluminum alkyls as co-catalyst suppress ethane formation or increase polymerization activity.

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.

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.

The present invention provides an adhesive composition including an ethylene/alpha-olefin copolymer; and a tackifier, wherein the ethylene/alpha-olefin copolymer has narrow molecular weight distribution together with a low density and an ultra low molecular weight, minimized number of unsaturated functional groups, and particularly a small amount of vinylidene among the unsaturated functional groups, thereby showing excellent physical properties.

The present invention provides an ethylene/alpha-olefin copolymer having narrow molecular weight distribution together with a low density and an ultra low molecular weight, minimized number of unsaturated functional groups, and particularly a small amount of vinylidene among the unsaturated functional groups to show excellent physical properties, and a method for preparing the same.

A catalyst system for olefin polymerization contains a main catalyst and a cocatalyst. The cocatalyst contains a twelve-membered ring compound represented by formula (M). The catalyst system is suitable for preparing polypropylene products having high stereoregularity and low ash, and can regulate the melt index of the products within a wide range by adjusting the amount of hydrogenation. It is also suitable for copolymerization systems to improve the copolymerization yield.

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A catalyst system for olefin polymerization contains a main catalyst and a cocatalyst. The cocatalyst contains a twelve-membered ring compound represented by formula (M). The catalyst system is suitable for preparing polypropylene products having high stereoregularity and low ash, and can regulate the melt index of the products within a wide range by adjusting the amount of hydrogenation. It is also suitable for copolymerization systems to improve the copolymerization yield.

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