Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a mono or dihalogenated hydrocarbon compound. Said catalyst systems have improved polymerization activity.

Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a brominated cyclic hydrocarbon. Said catalyst systems have improved polymerization activity.

Abstract: A catalyst system comprising the product obtained by contacting (a) a solid catalyst component containing Mg, Ti, halogen and at least an electron donor compound selected from 1,3-diethers; (b) an alkylaluminum cocatalyst; and (c) an ester of formula ROOC—(CH2)n—COOR in which n is an integer from 2 to 8, R groups, equal to or different from each other, are C1-C10 alkyl groups.

Abstract: The present invention relates to catalysts systems for the polymerization of ethylene and its mixtures with olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, and optionally an electron donor compound in a donor/Ti molar ratio lower than 1, (B) an aluminum alkyl compound and (C) a silicon compound of formula RImSi(ORII)n in which RI is C1-C20 alkyl group, RII is a secondary or tertiary alkyl group or a cycloalkyl having from 3 to 20 carbon atoms, m is an integer ranging from 0 to 3, and n is (4-m). The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (co)polymers having narrow Molecular Weight Distribution (MWD) and high activity.

Abstract: Process for the preparation of ethylene polymers having narrow MWD characterized by a F/E ratio lower than 35 carried out in the presence of a catalyst system comprising (a) a solid catalyst component comprising Ti atoms that are substantially in the +4 oxidation state, Mg, Cl, and optionally OR groups and internal donors in which R is a C1-C20 hydrocarbon group, in which the OR/Ti molar ratio is equal to or lower than 0.35 and the internal donor/Ti ratio is lower than 1, (b) an aluminum alkyl compound and (c) a compound selected from alkoxybenzenes of specified formula.

Abstract: A catalyst component for the polymerization of olefins comprises Mg, Ti, halogen, and an alpha-omega-diether represented by the general formula: (RO)—(CR1R2)n—(OR), wherein the number of n is from 5 to 10, R is an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons, and R1 and R2 are independently from each other hydrogen, an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons. The catalysts prepared with such component provide a high mileage for the production of polyolefins with a high bulk density of the polymer produced in gas-phase polymerization process or in slurry polymerization process. Such catalyst produces narrower MWD PE, if compared with other catalyst systems.

Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a mono or dihalogenated hydrocarbon compound. Said catalyst systems have improved polymerization activity.

Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a brominated cyclic hydrocarbon. Said catalyst systems have improved polymerization activity.

Abstract: The present invention relates to catalysts systems for the polymerization of olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, and halogen (B) an aluminum alkyl compound and (C) a halogenated germanium compound. Said catalyst systems have improved polymerization activity.

Abstract: The present invention relates to catalysts systems for the polymerization of ethylene and its mixtures with olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, (B) an aluminum alkyl compound and (C) an an acetal of formula HnC(OR1)4-n where n is O, 1 or 2 and R1 is C1-C10 hydrocarbon group.

Abstract: The present invention relates to catalysts systems for the polymerization of ethylene and its mixtures with olefins CH2?CHR wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, and optionally an electron donor compound in a donor/Ti molar ratio lower than 3, (B) an aluminum alkyl compound and (C) a silicon compound of formula Xm,R1nSi(OR2)4-(m+n)in which X is bromine or fluoride or a halogen containing hydrocarbon group, R1 is a C1-C10 aliphatic or alicyclic group, R2 is C1-C10 alkyl group, m is an integer ranging from 1 to 3, n is 0 or 1 provided that the sum m+n is not higher than 3. The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (copolymers having narrow Molecular Weight Distribution (MWD) and high activity.

Abstract: The present invention relates to catalysts for the polymerization of ethylene and its mixtures with olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, and optionally an electron donor compound in a donor/Ti molar ratio lower than 3, (B) an aluminum alkyl compound and (C) a silicon compound of formula RmSi(OEt)n in which R is C1-C20 alkyl group, m is an integer ranging from 1 to 3, n is (4-m) with the proviso that when R is equal to, or higher than, C3 m is 1 or 2. The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (co)polymers having narrow Molecular Weight Distribution (MWD) and high activity.

Abstract: The present invention relates to catalysts for the polymerization of olefins, in particular ethylene and its mixtures with olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising a solid catalyst component comprising Ti, Mg, halogen and optionally an electron donor, an aluminum alkyl compound and a particular class of silanes compounds as external electron donor compounds. The catalysts of the invention are suitably used in (co)polymerization processes of ethylene to prepare (copolymers having narrow Molecular Weight Distribution (MWD) and high activity.

Abstract: The present invention relates to catalysts systems for the polymerization of ethylene and its mixtures with olefins CH2?CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, (B) an aluminum alkyl compound and (C) an ether of formula ROMe in which R is an alkyl group linked to the oxygen atom through a tertiary carbon atom, and in which the molar ratio between the aluminum alkyl compound (B) and the ether compound (C) ranges from 5 to 50.

Abstract: A catalyst component for the polymerization of olefins comprises Mg, Ti, halogen, and an alpha-omega-diether represented by the general formula: (RO)—(CR1R2)n—(OR), wherein the number of n is from 5 to 10, R is an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons, and R1 and R2 are independently from each other hydrogen, an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons. The catalysts prepared with such component provide a high mileage for the production of polyolefins with a high bulk density of the polymer produced in gas-phase polymerization process or in slurry polymerization process. Such catalyst produces narrower MWD PE, if compared with other catalyst systems.

Abstract: The instant invention relates to a process for preparing a catalyst component for the polymerization of olefins. Catalysts prepared with this catalyst component provide a high mileage for the production of polyolefin with a high bulk density of the polymer produced therewith. Particularly, catalysts prepared with this catalyst component are suitable for the improved economical production of polyolefin in gas phase processes.

Abstract: The present invention relates to catalyst components for the polymerization of olefins comprising a titanium compound, having at least a Ti-halogen bond, and at least two electron donor compounds supported on a Mg dihalide, said catalyst component being characterized by the fact that at least one of the electron donor compounds is selected from ethers containing two or more ether groups which are further characterized by the formation of complexes with anhydrous magnesium dichloride in an amount less than 60 mmoles per 100 g of MgCl2 and by the failure of entering into substitution reactions with TiCl4 or by reacting in that way for less than 50% by moles, and at least another electron donor compound is selected from esters of mono or polycarboxylic acids. Said catalyst components are able to produce propylene polymers which, for high values of xylene insolubility, show a broad range of isotacticity.

Abstract: The present invention relates to catalyst components for the polymerization of olefins comprising a titanium compound, having at least a Ti-halogen bond, and at least two electron donor compounds supported on a Mg dihalide, said catalyst component being characterized by the fact that at least one of the electron donor compounds is selected from ethers containing two or more ether groups which are further characterized by the formation of complexes with anhydrous magnesium dichloride in an amount less than 60 mmoles per 100 g of MgCl2 and by the failure of entering into substitution reactions with TiCl4 or by reacting in that way for less than 50% by moles, and at least another electron donor compound is selected from esters of mono or polycarboxylic acids. Said catalyst components are able to produce propylene polymers which, for high values of xylene insolubility, show a broad range of isotacticity.

Abstract: Disclosed are a catalyst for polymerizing olefins containing a solid catalyst component containing titanium, magnesium and halogen as essential components (component (A)); an organic aluminum compound (component (B)); and a silane compound (component (C)) represented by general formula (1) wherein R1 and R2 independently represent a straight, branched or cyclic saturated aliphatic hydrocarbon group or a silyl group, a method of preparing polyolefins using the catalyst as well as novel trimethoxysilane compounds represented by the general formula (1) in which R1 is a straight saturated aliphatic hydrocarbon group having 2 to 10 carbon atoms, and R2 represents a methyl group. Use of the catalyst enables efficient production of polyolefins having a low molecular weight (MFR>20 (g/10 minutes)), a broad molecular weight distribution (MLMFR/MFR>22) and a high stereoregularity when applied to polymerization of olefins having 3 or more carbon atoms.

Abstract: A 3-alkoxypropionic ester derivative, an olefin polymerization solid catalyst component using the same, an olefin polymerization catalyst using the same, and a process for the preparation of a polyolefin using the same. The 3-alkoxypropionic ester derivative is represented by formula (I): ##STR1## wherein R.sup.1 represents a hydrocarbon group having from 1 to 10 carbon atoms; R.sup.2 represents a hydrocarbon group having from 1 to 20 carbon atoms; R.sup.3 represents a hydrocarbon group having from 1 to 20 carbon atoms; and R.sup.4 represents a branched hydrocarbon group having 3 or more carbon atoms.