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: There are provided; (i) a solid catalyst component obtained by contacting a trivalent titanium atom-containing solid catalyst component precursor (C) with a halogeno compound (A) of the 13 or 14 group of elements in the periodic table of the elements and an electron donor (B), or a solid catalyst component obtained by contacting an intermediate product with a titanium-halogen bond-carrying compound (D), the intermediate product being obtained by contacting the solid catalyst component precursor (C) with a halogeno compound (A?) of the 14 group of elements in the periodic table of the elements and the electron donor (B), or a solid catalyst component comprising a magnesium atom, a titanium atom, a halogen atom and an electron donor and having a relative surface area of not more than 30 m2/g, the catalyst component being superior in a particle form, and (ii) a catalyst comprising the solid catalyst component and an organoaluminum compound, the catalyst being high in polymerization activity.

Abstract: A solid titanium complex catalyst for polymerization and copolymerization of ethylene is prepared by the process comprising: (1) preparing a magnesium solution by reacting a halogenated magnesium compound with an alcohol; (2) reacting the magnesium solution with an ester compound having at least one hydroxyl group and a boron compound having at least one alkoxy group to produce a magnesium composition; and (3) producing a solid titanium catalyst through recrystallization by reacting the magnesium composition solution with a mixture of a titanium compound and a haloalkane compound; and optionally reacting the solid titanium catalyst with an additional titanium compound.

Abstract: A solid catalyst component for olefin polymerization characterized by being formed from (a) a magnesium compound, (b) titanium tetrachloride, (c) a phthalic diester and a derivative thereof, and either (d1) a hydroxylated hydrocarbon compound (phenol, etc.) represented by a specific formula or (d2) a mercapto-containing hydrocarbon compound (thiophenol, etc.) represented by a specific formula. With a catalyst obtained from this solid catalyst component, an olefin polymer can be obtained in extremely high yield. In particular, a propylene polymer which retains high stereoregularity can be obtained in extremely high yield.

Abstract: There is provided a process for producing a catalyst for olefin polymerization, which comprises the step of contacting (1) an organ aluminum compound, (2) an external electron donor compound and (3) a solid catalyst component obtained by a process comprising the steps of; (i) reducing a titanium compound represented by the following formula [I] with an organomagnesium compound in the presence of a fine particle and an organosilicon compound having an Si—O bond to obtain a solid product, and (ii) contacting the solid product, a halogenocompound having halogenation ability and an internal electron donor compound to obtaining the solid catalyst component.

Abstract: The invention relates to a process for the preparation of an olefin polymerisation catalyst component, said catalyst component and its use. The process is mainly characterized by the steps of (i) reacting in solution a magnesium compound containing an alkoxy group, a carboxylic acid halide and a four-valent titanium compound containing a halogen, for obtaining a dissolved reaction product and (ii) recovering a fraction of the reaction product from step (i) in particulate form by contacting the dissolved reaction product with a mixture of an aromatic and an aliphatic hydrocarbon, or by contacting the dissolved reaction product first with an aromatic hydrocarbon and then with an aliphatic hydrocarbon, the amount of aromatic and aliphatic hydrocarbon being at least 5 mol per mol of magnesium.

Abstract: A lower ?-alkene polymerization heterogeneous solid catalyst which comprises a hydrated magnesium chloride derived procatalyst, a cocatalyst comprising an organoaluminium compound and a selectivity control agent comprising an ester or ether. The procatalyst comprises a titanium tetrahalide supported on a magnesium chloride ester complex precursor. Magnesium chloride alcoholate is reacted with an activated carbonyl compound in the presence of a hydrocarbon and/or halohydrocarbon solvent to generate insitu an internal electron donor ester component of the precursor. The precursor is reacted with a titanium tetrahalide optionally in the presence of a hydrocarbon and/or halohydrocarbon solvent.

Abstract: There are disclosed a process for producing a solid catalyst component and a catalyst for ?-olefin polymerization, and a process for producing an ?-olefin polymer, wherein the process for producing a solid catalyst component comprises the steps of: (1) reducing a specific titanium compound with an organomagnesium compound in the presence of an organosilicon compound having an Si—O bond (and an ester compound), thereby obtaining a solid product, and (2) contacting the solid product with a halogeno compound of the 14 group element, at least one member selected from the group consisting of an electron donor compound and an organic acid halide, and a compound having a Ti-halogen bond, thereby obtaining the solid catalyst component.

Abstract: Solid catalyst components comprising Ti,Mg, halogen and internal electron-donor compound selected from the 1,3-diethers of formula (I) in which R is a C1-C10 alkyl group, R1 is a linear or branched primary alkyl radical having at least three carbon atoms, optionally containing a heteroatom, and R2 is a secondary alkyl or cycloalkyl radicals different from i-propyl, optionally containing a heteroatom. The catalysts obtained by using as internal electron-donor compound the said 1,3-diethers display in the (co)polymerization of olefins an excellent balance of activity and stereospecificity that cannot be reached with the ethers known in the art.

Abstract: A MgCl2.mEtOH.nH2O adducts, where 3.4<m≦4.4, 0≦n≦0.7, characterized by an X-ray diffraction spectrum, taken under the condition set forth above, in which, in the range of 2&thgr; diffraction angles between 5° and 10°, at least two diffraction lines are present at diffraction angles 2&thgr; of 9.3±0.2°, and 9.9±0.2°, the most intense diffraction lines being the one at 2&thgr; of 9.3±0.2°, the intensity of the other diffraction line being less than 0.4 times the intensity of the most intense diffraction line. Catalyst components obtained from the adducts of the present invention are capable to give catalysts for the polymerization of olefins characterized by enhanced activity and/or porosity with respect to the catalysts prepared from the adducts of the prior art.

Abstract: The present invention relates to an adduct comprising MgCl2, an alcohol (ROH) in which R is a C1-C10 hydrocarbon group, and a compound containing a transition metal M selected from the Groups 3 to 11 or the lanthanide or actinide groups of the Periodic Table of the Elements (new IUPAC version) in an amount such as to give a weight of M atoms lower than 10% based on the total weight of the adduct. The catalyst components that are obtained by reacting the adducts with halogenating agents show very high specific activity.

Abstract: A solid titanium complex catalyst for polymerization and copolymerization of ethylene is prepared by the process that includes: (1) preparing a magnesium solution by reacting a halogenated magnesium compound with an alcohol; (2) reacting the magnesium solution with an ester compound having at least one hydroxyl group and a silicon compound having an alkoxy group to produce a magnesium composition; and (3) producing a solid titanium catalyst by reacting the magnesium composition solution with a mixture of a titanium compound and a haloalkane compound; and optionally reacting the solid titanium catalyst with an additional titanium compound.

Abstract: There are provided: (I) a solid catalyst component (A-1) for olefin polymerization, which is obtained by a process comprising the step of contacting: (a-1) a carrier of carboxyl group-carrying polymer particles having an average particle diameter of from 1 to 300 &mgr;m, and (b) a transition metal compound of the number 4 group of metals in the periodic table of elements; (II) a catalyst for olefin polymerization, which is obtained by a process comprising the step of contacting: (A-1) the above solid catalyst component, and (B) at least one compound selected from the group consisting of an organoaluminum compound and an organoaluminumoxy compound; (III) a process for producing an olefin polymer, which comprises the step of polymerizing an olefin in the presence of the above catalyst; and (IV) a process for producing the above solid catalyst component (A-1), which comprises the step of contacting: (a-1) the above carrier, and (b) the above transition metal compound.

Abstract: The present invention relates to a catalyst for homo-polymerization or co-polymerization of ethylene, or more particularly to a solid complex titanium catalyst for homo-polymerization or co-polymerization of ethylene. The catalyst may be produced by preparing a magnesium solution by contact-reacting a magnesium halide compound with an alcohol. Reacting the solution with an ester compound and a boron compound. Then reacting the solution with a mixture of a titanium compound and a silicon compound.

Abstract: A method of making a solid procatalyst composition for use in a Ziegler-Natta olefin polymerization catalyst composition, said method comprising: contacting a solid precursor composition comprising magnesium, titanium, and alkoxide moieties with a titanium halide compound and an internal electron donor in any order, in a suitable reaction medium to prepare a solid procatalyst composition, separating the solid procatalyst from the reaction medium, further exchanging residual alkoxide functionality of the solid procatalyst composition for chloride functionality by contacting the same two or more times with benzoyl chloride halogenating agent under metathesis conditions for a period of time sufficient to prepare a solid procatalyst composition having a decreased alkoxide content compared to the alkoxide content of the solid procatalyst composition before said exchange, and recovering the solid procatalyst composition.

Abstract: The present invention relates to catalyst components for the polymerization of olefins comprising Mg, Ti, halogen and at least two electron donor compounds, said catalyst component being characterized by the fact that at least one of the electron donor compounds, present in an amount from 20 to 50% by mol with respect to the total amount of donors, is selected from esters of succinic acids which are not extractable, for more than 25% by mol and at least another electron donor compound which is extractable, for more than 35%. The said catalyst component are capable to give polymers with high xylene insolubility, high stereoblock content and broad MWD suitable for making the polymers usable in the BOPP sector.

Abstract: Cyclopolyenic 1,3-diethers wherein the carbon atom in position 2 belongs to a particular cyclic or polycyclic structure containing two or three unsaturations, solid catalyst components and catalysts therefrom, the catalysts comprising the reaction product of:

Abstract: Process for preparing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, said process comprising the steps of a) preparing a solution of a complex of a Group 2 metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid reaction medium; b) adding said solution of said complex to at least one compound of a transition material to produce an emulsion, the dispersed phase of which contains more than 50 mol % of the Group 2 metal in said complex; c) agitating the emulsion, optionally in the presence of an emulsion stabilizer, in order to maintain the droplets of said dispersed phase within the average size range 5 to 200 m; d) solidifying said droplets of the dispersed phase; and e) recovering the solidified particles of the olefin polymerisation catalyst component, wherein a turbulence minimizing agent (TMA) is added to the reaction mixture before solidifying said droplets of the disperse

Abstract: The present invention is to provide a composite carrier, which is spheric particles obtainable by contacting magnesium halide with one or more electron donor compounds to form a solution, then mixing the solution with silica material having an average particle size of less than 10 microns to form a mixture, and drying the mixture through spray drying process. The present invention is also to provide a catalyst component comprising said composite carrier. When the catalyst component is used together with a cocatalyst component in propylene polymerization, it exhibits higher polymerization activity and stereospecificity, and can be used to prepare high impact resistant ethylene-propylene copolymer having high ethylene content.

Abstract: The present invention relates to a method for producing a polymer and copolymer of ethylene, and more particularly to a method for producing an ethylene polymer and copolymer by reacting a compound of an organic metal of Group 2, 12, or 13 on the periodic table of elements with an alkoxy silane compound in the presence of a titanium catalyst, the said titanium catalyst being produced by a process of preparing a magnesium compound by contact-reacting a halogenated magnesium compound and alcohol, of reacting the said solution with an ester compound which contains at least one hydroxy group and a silicon compound containing an alkoxy group, and also of reacting it with a solid matter obtained by reaction of a mixture of a titanium compound and a silicon compound with a titanium compound.

Abstract: Disclosed are catalysts for the polymerization of alpha-olefins which comprise the reaction product of: (a) an Al-alkyl compound; (b) a silicon compound containing at least one Si—OR or Si—OCOR or Si—NR2 bond, R being a hydrocarbyl radical; (c) a solid comprising, as essential support, a Mg dihalide in active form and, supported thereon, a Ti halide or a halo-Ti-alcoholate and a particular type of electron donor compound. The present invention refers to new supported components of catalysts for the polymerization of CH2═CHR olefins wherein R is an alkyl radical with 1 to 4 carbon atoms, or an aryl radical, and mixtures of said olefins with ethylene and the catalysts obtained from said components.

Abstract: Solid catalyst components and catalysts which contain (a) magnesium compound, (b) titanium tetrachloride, and (c) a phthalic acid diester or its derivative are useful in the synthesis of olefin polymers in high yields. Particularly, propylene polymers can be obtain in very high yields while retaining high stereoregularity.

Abstract: A pre-catalyst is formed by reacting butylethylmagnesium with an alcohol to form a magnesium alkoxide compound, followed by contacting the magnesium alkoxide compound with a phosporous compound to form a magnesium alkoxide phosphorous compound mixture. The magnesium alkoxide phosphorous compound mixture is subsequently reacted with TiCl4 to form a MgCl2 support. The MgCl2 support is then contacted with an internal donor while being heated to form a first catalyst slurry, which is then contacted with TiCl4 while being heated to form a second catalyst slurry. The second catalyst slurry is next contacted with TiCl4 while being heated to form a third catalyst slurry, which is washed and dried, resulting in a highly active pre-catalyst with controlled morphology. The pre-catalyst may be combined with one or more co-catalysts and optionally one or more external electron donors to form an active catalyst system, which may be used for polymerization of olefins.

Abstract: A supported catalyst composition comprising the reaction product of i) a magnesium halide, ii) a solvent, iii) an electron donor compound, iv) and a transition metal compound; an inert support; and a cocatalyst composition wherein the supported catalyst is substantially free of other alcohols and wherein the molar ratio of the first alcohol to magnesium is less than or equal to 1.9. Methods of making supported catalyst compositions and methods of making polymers with supported catalysts.

Abstract: The present invention relates to a catalyst for polymerization and co-polymerization of ethylene. More particularly, the present invention relates to a solid titanium catalyst containing magnesium, wherein said catalyst is produced by preparing a magnesium solution by contact-reacting a halogenated magnesium compound with alcohol; reacting said solution with an ester compound having at least one hydroxy group, or a phosphorous compound and a silicon compound having alkoxy groups; producing a solid component with an adjusted particle morphology by adding a mixture of a titanium compound and a silicon compound; reacting the same with an aluminum compound; and then reacting the same with a titanium compound, or a titanium compound and a vanadium compound. As a result, the catalyst of the present invention has high catalytic activity with excellent catalyst morphology.

Abstract: The present invention provides a method for producing a new catalyst of high polymerization activity for homo- or co-polymerization of ethylene, or more particularly a method for producing a titanium solid complex catalyst supported on a carrier containing magnesium, wherein said catalyst is capable of producing polymers of high bulk density and narrow particle size distribution with few fine particles.

Abstract: Olefin polymers with a broad molecular weight distribution can be obtained while maintaining the high stereoregularity of the polymers by polymerizing olefins using a catalyst comprising (A) a solid catalyst component prepared by contacting (a) a dialkoxymagnesium, (b) a tetravalent titanium halide compound, and (c) an electron donor compound one another, (B) an organoaluminum compound of the formula R1pAlQ3-p, and (C) an aminosilane compound of the formula R2R3Si(OR4)2.

Abstract: Process for the polymerization of olefins CH=CHR, in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, carried out in the presence of a catalyst component (A) comprising Mg, Ti and halogen as essential elements and of a catalyst component (B) capable to produce, under the same polymerization conditions, a polymer with an average particle size lower than that obtainable with the said catalyst component A. The said process provides polymers with increased bulk density.

Abstract: The present invention relates to a solid catalyst component for the polymerization of olefins CH2═CHR in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, comprising Mg, Ti, halogen and an electron donor selected from substituted succinates of a particular formula. Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: The present invention provides a method for producing a new catalyst of high catalytic activity and superior catalyst morphology for homo- or co-polymerization of ethylene, or more particularly a method for producing a titanium solid complex catalyst supported on a carrier containing magnesium, wherein said catalyst of high polymerization activity is capable of producing polymers of high bulk density.

Abstract: Catalyst component for the polymerization of olefins obtainable by contacting: (i) a magnesium halide, or a suitable precursor; (ii) a monofunctional electron donor compound (MD) selected from ethers, esters, amines or ketones, used in such amounts to have Mg/MD molar ratios of at least 50; (iii) a titanium compound of formula Ti(ORI)n-yXy, where n is the valence of titanium, y is a number between 1 and n, X is halogen, and RI is a C1-C15 hydrocarbon group and, optionally, (iv) an electron donor compound (ED). The said catalyst component shows improved activity in the polymerization of olefins.

Abstract: A process (I) for producing an &agr;-olefin polymerization catalyst whereby (1) a titanium compound is reduced by an organomagnesium compound in the presence of an organosilicon compound to produce a reduction solid, (2) the reduction solid is aged to produce a solid product, (3) the solid product is contacted with an ether compound, titanium tetrachloride and an organic acid halide compound, to produce an organic acid halide-treated solid, (4) the organic acid halide-treated solid is contacted with a mixture of an ether compound, titanium tetrachloride and an ester compound, or with a mixture of an ether compound and titanium tetrachloride to produce a solid catalyst component containing a titanium compound, and (5) the solid catalyst component is contacted with an aluminum compound and an electron donor compound to produce a catalyst for &agr;-olefin polymerization. A process (II) for producing an &agr;-olefin polymer using a catalyst produced by process (I).

Abstract: A catalyst component for the (co)polymerization of olefins is provided. The catalyst comprises titanium, magnesium halogen and a mixed electron-donor and a catalyst for the (co)polymerization of olefins comprising:(A) the catalyst component; (B) an organic aluminum compound; and (C) an organic silicon compound. A polymer with high and adjustable stereospecificity and broad molecular weight distribution can be prepared by using the catalyst.

Abstract: Process for preparing an olefin polymerisation catalyst component comprising magnesium halide, titanium halide and a carboxylic acid ester electron donor, in which the precursors of its constituents are reacted in solution from which the component is eventually precipitated, this precipitation being accompanied by co-precipitation of one or more oligoesters of the carboxylic acid formed in a controlled manner. The component is employed, together with an organometallic co-catalyst, for polymerisation of C2-C1-0 &agr;-olefins.

Abstract: The present invention relates to catalysts particularly suitable for the sterospecific polymermerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatoms containing esters of malonic acids. Polymers produced by the catalysts have high isotactic index expressed in terms of high xylene insolubility.

Abstract: An olefin polymerization catalyst is described which includes: (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor and a titanium compound, and (B) an organoaluminum compound. The present invention is also directed to a process for preparing polyolefins using the aforesaid catalyst system to polymerize olefins.

Abstract: A method for making a solid catalyst component for use in a Ziegler-Natta catalyst includes combining a porous particulate support with a magnesium source in a hydrocarbon solvent to form a mixture, the magnesium source including a hydrocarbon soluble organomagnesium compound and a hydrocarbon insoluble anhydrous inorganic magnesium-halogen compound. The organomagnesium compound is halogenated and the mixture is reacted with a titanium compound or vanadium compound to form the solid catalyst component. The solid catalyst component is then recovered and combined with an organoaluminum cocatalyst to form a Ziegler-Natta catalyst which is advantageously used for the polymerization of olefins, particularly alk-1-enes such as ethylene, propylene, 1-butene, and the like. The catalyst can optionally include internal and external electron donors.

Abstract: The present invention relates to a process for the polymerization of olefins using catalyst components and catalysts obtained therefrom comprising Ti, Mg, halogen and an electron donor compound selected from heteroatoms containing esters of malonic acids. The catalysts are particularly suitable for the sterospecific polymermerization of olefins having high isotactic index expressed in terms of high xylene insolubility.

Abstract: A process for the preparation of a supported catalyst system, an inorganic carrier material being reacted with a metal compound of the formula M1(R1)r(R2)5(R3)t(R4)u  I in the presence of an inert solvent in a first step and, in a subsequent step, the suspension thus obtained being reacted with a metallocene complex and a compound forming metallocenium ions, in which process the solvent is not removed after the first step and the subsequent step is carried out without isolation of the pretreated carrier material thus obtained.

Abstract: There are provided (1) a process for producing a solid product, which comprises the step of reducing a titanium compound represented by the following formula [I] with an organomagnesium compound in the presence of an organosilicon compound having an Si—O bond, an inorganic fine particle and optionally an ester compound, (2) a process for producing a solid catalyst component, which comprises the step of contacting the solid product obtained by the above process, a halogenation ability-carrying halogeno compound, and an inner electron donor compound, (3) a process for producing a catalyst, which comprises the step of contacting the solid catalyst component obtained by the above process, an organoaluminum compound, and an outer electron donor compound, and (4) a process for producing an olefin polymer, which comprises the step of polymerizing an olefin in the presence of the catalyst obtained by the above process.

Abstract: The present invention relates to a solid catalyst component for the polymerization of olefins CH2═CHR in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, comprising Mg, Ti, halogen and an electron donor selected from maleates of a particular formula. Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: There are provided a process for producing a catalyst for &agr;-olefin polymerization, which comprises the step of contacting (1) a solid catalyst component having Ti, Mg and a halogen as essential components, (2) an organoaluminum compound and (3) a compound having a —C—O—C—O—C— bond group in a closed ring structure with one another; and a process for producing an &agr;-olefin polymer, which comprises the step of homopolymerizing or copolymerizing an &agr;-olefin in the presence of a catalyst for &agr;-olefin polymerization produced by the above process.

Abstract: A method for increasing the solubility of a magnesium halide includes providing an electron donating solvent, contacting a magnesium halide with the solvent; and providing an electron donor compound to form a magnesium halide composition. The composition is characterized by a solubility in the electron donor solvent that does not decrease up to the boiling point of the solvent. A polymerization catalyst precursor composition comprises the product of mixing the magnesium halide composition with a transition metal compound. Active catalysts prepared from such precursors and a methods of polymerization using such catalysts are also disclosed.

Abstract: A spray-dried catalyst precursor composition and method of making a spray-dried catalyst precursor composition with an inert filler, magnesium, a transition metal, solvent, and one electron donor compound. The catalyst precursor composition is substantially free of other electron donor compounds, the molar ratio of the electron donor compound to magnesium is less than or equal to 1.9, and comprises spherical or substantially spherical particles having a particle size of from about 10 to about 200 &mgr;m. Catalysts made from the spray-dried catalyst precursors and polymerization methods using such catalysts are disclosed.

Abstract: The present invention relates to catalyst components for the polymerization of olefins, and to the catalyst obtained therefrom, particularly suitable for the stereospecific polymerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatom containing esters of malonic acids (heteroatom containing malonates). Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: The present invention relates to catalyst components for the polymerization of olefins, and to the catalyst obtained therefrom, particularly suitable for the stereospecific polymerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatom containing esters of malonic acids (heteroatom containing malonates). Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: The present invention relates to catalyst components for the polymerization of olefins, and to the catalyst obtained therefrom, particularly suitable for the stereospecific polymerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatom containing esters of malonic acids (hereroatom containing malonates). Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: The present invention relates to catalyst components for the polymerization of olefins, and to the catalyst obtained therefrom, particularly suitable for the stereospecific polymerization of olefins, comprising Ti, Mg, halogen and an electron donor compound selected from heteroatom containing esters of malonic acids (heteroatom containing malonates). Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.

Abstract: There are provided:

Abstract: Solid catalyst components and catalysts which comprise (a) a magnesium compound, (b) titanium tetra chloride, and (c) a phthalic acid diester or its derivative represented by a particular formula, can afford polymers of olefins in very high yield. Particularly, propylene polymers can be obtained in very high yield while retaining high stereoregularity. Moreover, they have high responsiveness to hydrogen.