Abstract: The invention relates to a process for the production of polyethylene. The polymerisation takes place in the presence of a catalyst system comprising a hydrocarbon solution containing 1) a dialkoxy magnesium compound and 2) an organic oxygen containing titanium compound further comprising an inorganic oxide support and an activator.

Abstract: This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.

Abstract: This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.

Abstract: This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.

Abstract: This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.

Abstract: The invention relates to a catalyst system for the production of ultrahigh molecular weight polyethylene comprising I. a solid reaction product obtained by reaction of: (a) a hydrocarbon solution comprising (1) an organic oxygen containing magnesium compound or a halogen containing magnesium compound and (2) an organic oxygen containing titanium compound and (b) a mixture comprising a metal compound having the formula MeRnX3-n wherein X is a halogenide, Me is a metal of Group III of Mendeleev's Periodic System of Chemical Elements, R is a hydrocarbon radical containing 1-10 carbon atoms and 0?n?3 and a silicon compound of formula RmSiCl4.m wherein 0?m?2 and R is a hydrocarbon radical containing 1-10 carbon atoms wherein the molar ratio of metal from (b): titanium from (a) is lower than 1:1 II. an organo aluminium compound having the formula AIR3 in which R is a hydrocarbon radical containing 1-10 carbon atoms and III.

Abstract: The various embodiments herein disclose a method for making a Zieglaer catalyst including a reaction product of a dispersed magnesium alkoxide or a dispersed mixture of magnesium alkoxide and silica with a transition metal compound of titanium, zirconium, vanadium or chromium, and a chlorine containing organoaluminum mixed together with two additional components comprising a halogen containing silicon compound and aliphatic primary halogenated hydrocarbons respectively. The embodiments also provide a method of polymerization of 1-olefin monomers using the Ziegler catalyst.

Abstract: This invention relates to a supported nonmetallocene catalyst and preparation thereof. The supported nonmetallocene catalyst can be produced with a simple and feasible process and is characterized by an easily controllable polymerization activity. This invention further relates to use of the supported nonmetallocene catalyst in olefin homopolymerization/copolymerization, which is characterized by a lowered assumption of the co-catalyst as compared with the prior art.

Abstract: The present invention relates to an ultrahigh-molecular-weight ethylene copolymer powder having an intrinsic viscosity (?) of 10 dl/g to 34 dl/g, obtainable by copolymerizing ethylene and at least one olefin selected from the group consisting of ?-olefins having 3 to 20 carbon atoms, cyclic olefins having 3 to 20 carbon atoms, compounds represented by the formula CH2?CHR1 wherein R1 is an aryl group having 6 to 20 carbon atoms, and linear, branched or cyclic dienes having 4 to 20 carbon atoms, wherein (1) a molded article of the copolymer powder has a haze of from 30% to 80% and (2) the copolymer powder has a bulk density of from 0.35 g/cm3 to 0.6 g/cm3.

Abstract: Broad molecular weight polyethylene and polyethylene having a bimodal molecular weight profile can be produced with chromium oxide based catalyst systems employing alkyl silanols. The systems may also contain various organoaluminum compounds. Catalyst activity and molecular weight of the resulting polyethylene may also be tuned using the present invention.

Abstract: The present invention relates to a multimodal polyethylene composition wherein (i) the composition has an MFR2 of 0.1 to 100 g/10 min, (ii) the shear thinning index SHI(1,100) and the log MFR2 of the composition satisfy the following relation: SHI(1,100)??10.58 log MFR2 [g/10 min]/(g/10 min)+12.94, and (iii) the composition has an environmental stress crack resistance ESCR of 10 h or more. Furthermore, the present invention relates to a process for the production of said composition, an injection moulded article, in particular a cap or closure, comprising said composition and to the use of said composition for the production of an injection moulded article.

Abstract: A Ziegler-Natta procatalyst composition in the form of solid particles and comprising magnesium, halide and transition metal moieties, said particles having an average size (D50) of from 10 to 70 ?m, characterized in that at least 5 percent of the particles have internal void volume substantially or fully enclosed by a monolithic surface layer (shell), said layer being characterized by an average shell thickness/particle size ratio (Thickness Ratio) determined by SEM techniques for particles having particle size greater than 30 ?m of greater than 0.2.

Abstract: A method for preparing a titanium-containing Ziegler-Natta catalyst is disclosed. A dialkyl magnesium compound, a trialkyl aluminum compound, and a polymethylhydrosiloxane are first combined in a hydrocarbon solvent. That product is then combined with dry, alcohol-free magnesium chloride. A solid product from the reaction with the magnesium chloride component is isolated and washed with a hydrocarbon solvent. The washed solid product is then combined with an alkyl aluminum dichloride or a dialkyl aluminum chloride to give the catalyst. The catalyst is suitable for both slurry and gas-phase olefin polymerizations. Polyolefins produced with the catalyst have broad molecular weight distributions and narrow distributions of relatively large particles.

Abstract: Film formed from a polyethylene resin composition which obeys a dynamic rheological relationship at 190° C. between melt storage modulus G?, measured in Pa and at a dynamic frequency where the loss modulus G?=3000 Pa, and dynamic complex viscosity ?*100, measured in Pa·s at 100 rad/s, such that (a) G?(G?=3000)>?0.86?*100+z where z=3800, and at the same time (b) G?(G?=3000)>0.875?*100?y where y=650, and having an impact strength (DDT) of at least 250 g, measured on 15 ?m thick film (blown under conditions with BUR=5:1 and Neck Height=8×D) conditioned for 48 hours at 20°-25° C., according to ASTM D1709.

Abstract: Silica-coated alumina activator-supports, and catalyst compositions containing these activator-supports, are disclosed. Methods also are provided for preparing silica-coated alumina activator-supports, for preparing catalyst compositions, and for using the catalyst compositions to polymerize olefins.

Abstract: A polyethylene may be prepared using a mixture of a silica supported catalyst and a magnesium chloride supported catalyst. By changing the ratio of the two catalysts, the polyethylene produced may have a varying bulk density and shear response. The method allows for the tuning or targeting of properties to fit a specific application, such as a blow molding or vapor barrier film.

Abstract: A fiber and a process for obtaining same from a high-modulus polyethylene, extrudable in state-of-the-art equipment and in the absence of previous solubilization in any kind of organic solvent is described, the process comprising providing such a polyethylene, introducing it in a state-of-the-art extruder, extruding it according to a temperature pattern, obtaining an extrudate that is directed to a cooling bath to have its temperature reduced, then directing the extrudate to a first stretcher where it is stretched or drawn into a fiber of improved tenacity, at a first velocity v1, then heating the fiber at nearly 90° C. and then directing said fiber to a second stretcher to be drawn at a final velocity v2, wherein v1<v2, at a draw ratio of 2/1 until 65/1. The tenacity of the polyethylene fiber obtained by the said process attains at least 4 gf/den, which makes it useful to naval and offshore applications.

Abstract: The present invention relates to a process for the preparation of catalytic support and the supported bimetallic catalysts, used in the production of ethylene homopolymers and ethylene copolymers with ?-olefins, of high and ultra high molecular weight with broad molecular weight distribution, in gas or liquid phase polymerization processes, the latter being in slurry, bulk or suspension, and the products obtained from these processes.

Abstract: A fiber and a process for obtaining same from a high-modulus polyethylene, extrudable in state-of-the-art equipment and in the absence of previous solubilization in any kind of organic solvent is described, the process comprising providing such a polyethylene, introducing it in a state-of-the-art extruder, extruding it according to a temperature pattern, obtaining an extrudate that is directed to a cooling bath to have its temperature reduced, then directing the extrudate to a first stretcher where it is stretched or drawn into a fiber of improved tenacity, at a first velocity v1, then heating the fiber at nearly 90° C. and then directing said fiber to a second stretcher to be drawn at a final velocity v2, wherein v1<v2, at a draw ratio of 2/1 until 65/1. The tenacity of the polyethylene fiber obtained by the said process attains at least 4 gf/den, which makes it useful to naval and offshore applications.

Abstract: The present invention provides a high-activity solid main catalyst component for ethylene polymerization, a process for preparing the same and a catalyst containing the same. The main catalyst component consists essentially of a magnesium compound, a titanium compound, an electron donor, an alkyl aluminum compound and fumed silica, and is prepared by a process comprising the step of: reacting powdered magnesium with an alkyl halide to form a magnesium compound in the nascent state; adding the magnesium compound in the nascent state together with a titanium compound and an alkyl aluminum compound into an electron donor to form a complex; adding and well dispersing a fumed silica thereto to form a homogeneous thick mixture; molding and drying the mixture to form main catalyst component particles with good particle morphology; and optionally, dispersing the main catalyst component particles into a hydrocarbon solvent or a mineral oil to form a slurry.

Abstract: Broad molecular weight polyethylene and polyethylene having a bimodal molecular weight profile can be produced with chromium oxide based catalyst systems employing alkyl silanols. The systems may also contain various organoaluminum compounds. Catalyst activity and molecular weight of the resulting polyethylene may also be tuned using the present invention.

Abstract: The present invention provides an ethylene polymerization catalyst. The present invention also provides a process for preparing the ethylene polymerization catalyst, comprising reacting powdered magnesium with an alkyl halide of formula RX in the presence of an ether solvent to form a magnesium compound having a structure represented by the formula (RMgX)p(MgX2)q, in which R is an alkyl group having from 3 to 12 carbon atoms, X is halogen, and molar ratio of q to p is in the range of from larger than 0 to 1, impregnating the magnesium compound onto silica carrier, reacting the silica loading the magnesium compound with an alkyl halide of formula R1X, a titatium compound and an alkyl aluminum compound to form a main catalyst component, contacting the main catalyst component with a cocatalyst component to form catalyst for ethylene polymerization. The present invention also relates to the use of the catalyst in the polymerization of ethylene.

Abstract: Polyolefins may be prepared using a cocatalyst conforming to the formula: AIRz(Xz)nLzm wherein Rz is a linear or branched organic moiety having at least 5 carbons and Xz is a linear or branched organic moiety having at least 5 carbons or a heterocyclic moiety having at least 4 atoms and can be anionic or di-anionic. The aluminum complex may also be in the form of an adduct complex where Lz is a Lewis base and m=1-3. The cocatalyst Rz components are selected such that they do not react with water under polymerization conditions to form a species that is highly soluble in the polymerization diluent. Use of the specified cocatalyst reduces fouling during metallocene-catalyzed runs and “post-metallocene hangover” when the same production equipment is transitioned to non-metallocene catalyst runs using catalysts such as chromium.

Abstract: A process for producing a Gp 2/transition metal olefin polymerisation catalyst component, in which a Gp 2 complex is reacted with a transition metal compound so as to produce an oil-in-oil emulsion, the disperse phase containing the preponderance of the Gp 2 metal being selectively sorbed on a carrier to provide a catalyst component of excellent morphology. Polymerisation of olefins using a catalyst containing such a component is also disclosed.

Abstract: The present invention relates to a method for producing a propylene polymer having a very high melt flowability, specifically to a method for producing an isotactic propylene polymer having a dramatically improved melt flowability with a relatively high production yield in convenient way, by improving the reactivity of hydrogen that is served as a molecular weight controlling agent in propylene polymerization.

Abstract: The present invention provides a novel process for preparing a catalyst useful in gas phase polymerization of olefins wherein the physical properties of the polymer and the productivity of the catalyst can be altered depending on the sequence of addition of the catalyst components. The catalyst consists of compounds of Ti, Mg, Al and optionally an electron donor supported on an amorphous support.

Abstract: Propylene homopolymers, wherein, in their separation according to tacticity by first dissolving the polymers in boiling xylene, then cooling the solution to 25° C. at a cooling rate of 10° C./h and then, with ascending temperature, separating the propylene homopolymers into fractions of different tacticity, either one or more of the conditions that i) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 112° C. is greater than 20% by weight or ii) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 117° C. is greater than 8% by weight or iii) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 122° C. is greater than 1% by weight, are satisfied.

Abstract: Described herein is a prepolymerized catalyst encapsulated with macromolecular monomers which is prepared by adding olefin mononers and diene compounds to a solid complex titanium catalyst for olefin polymerization and then polymerizing, and also relates to a method for polymerization or copolymerization capable of preparing polyolefins with high melt strength by polymerizing the olefin by using said catalyst.

Abstract: A process for preparing spherical support particles used in the preparation of catalytic components for the polymerization of olefins by (a) forming an emulsion of an adduct of a Mg dihalide and a Lewis base compound in a liquid medium, and (b) cooling the emulsion by transferring it into a cooling bath containing a cooling liquid in motion wherein the cooling liquid is moving inside a tubular zone and the ratio Ve/Vref of the velocity (Ve) of the emulsion coming from step (a) to the velocity of the cooling liquid (Vref) of step (b) is between 0.25 and 4. The resulting spherical support particles have a very narrow size distribution and particularly regular morphology.

Abstract: Disclosed is a new titanium based catalyst system for (co)-polymerizing ethylene or ethylene with alpha-olefin having 3 to 10 carbons. The catalyst is obtained by contacting a magnesium halide support with an aluminum compound and with a titanium halide compound and then treating the resulting solid with a magnesium-amide complex. The catalyst system is suitable for producing ethylene polymer and co-polymer with narrow molecular weight distribution as well as improved branching compositional distribution.

Abstract: A modified aluminum oxy compound (A) obtained by reacting an aluminum oxy compound (a), water (b) and a compound having a hydroxyl group (c); a polymerization catalyst component comprising the modified aluminum oxy compound; a polymerization catalyst obtained by contacting said modified aluminum oxy compound (A), a transition metal compound (B) and optionally an organoaluminum compound (C) and a specified boron compound; and a process for producing an olefin polymer or an alkenyl aromatic hydrocarbon polymer with the polymerization catalyst.

Abstract: A process for the preparation of an olefin polymerization catalyst component containing a magnesium dihalide, a titanium tetrahalide, and a dicarboxylic acid di- oligo- or polyester as internal electron donors is disclosed. A catalyst component and its use for the polymerization of &agr;-olefins such as propene are also disclosed.

Abstract: The present invention provides a catalyst system that exhibits unexpected control of desired properties in polyolefin products. The catalyst system includes a titanium-supported catalyst in combination with a mixture of tetraethoxysilane (TEOS) and dicyclopentyldimethoxy-silane (DCPMS). This catalyst system has been found to be effective in making polypropylene and polypropylene copolymers having relatively high melt flow rates and moderately broad molecular weight distribution.

Abstract: A modified aluminum oxy compound(A) obtained by reacting an aluminum oxy compound(a), water (b) and a compound having a hydroxyl group(c); a polymerization catalyst component comprising the modified aluminum oxy compound; a polymerization catalyst obtained by contacting said modified aluminum oxy compound(A), a transition metal compound(B) and optionally an organoaluminum compound(C) and a specified boron compound; and a process for producing an olefin polymer or an alkenyl aromatic hydrocarbon polymer with the polymerization catalyst.

Abstract: The invention relates to an improved olefin catalyst, a method of in situ-activated catalyst preparation and a process for the polymerization of olefinic monomers via, for example, a titanium trichloride/magnesium dichloride/tetrahydrofuran reaction product catalyst precursor. The activated catalyst is prepared in situ in a polymerization reactor using an alumoxane based co-catalyst wherein the cumbersome traditional steps of catalyst activation and isolation, prior to polymerization are eliminated. An unexpected advantage of this invention is a significant increase in catalyst productivity while maintaining a relatively constant value of the bulk density of polymeric materials produced while concomitantly producing a polymeric product having a broad molecular weight distribution compared with typical alumoxane-activated metallocene catalysts.

Abstract: The invention relates to an improved olefin catalyst, a method of in situ-activated catalyst preparation and a process for the polymerization of olefinic monomers via, for example, a titanium trichloride/magnesium dichloride/tetrahydrofuran reaction product catalyst precursor. The activated catalyst is prepared in situ in a polymerization reactor using an alumoxane based co-catalyst wherein the cumbersome traditional steps of catalyst activation and isolation, prior to polymerization are eliminated. An unexpected advantage of this invention is a significant increase in catalyst productivity while maintaining a relatively constant value of the bulk density of polymeric materials produced while concomitantly producing a polymeric product having a broad molecular weight distribution compared with typical alumoxane-activated metallocene catalysts.

Abstract: Solid catalyst component for the polymerization of olefins, includes the product of the direct reaction, with no subsequent reactions with reducing organometallic compounds, between a titanium compound and a support obtained by contacting a metal oxide containing hydroxyl groups with a solution containing A) a magnesium chloride; B) from 1 to 6 moles of an alcohol per mole of magnesium chloride, in a halogenated hydrocarbon or aromatic hydrocarbon organic solvent C) capable of bringing the magnesium chloride in solution in quantities greater than or equal to 5 grams per liter in the presence of the above-mentioned quantities of alcohol B), the solvent not being able to form adducts with the magnesium chloride.

Abstract: The invention relates to a process for uniformly dispersing a transition metal metallocene complex on a carrier comprising (1) providing silica which is porous and has a particle size of 1 to 250 microns, having pores which have an average diameter of 50 to 500 Angstroms and having a pore volume of 0.5 to 5.0 cc/g; (2) slurrying the silica in an aliphatic solvent having a boiling point less than 110° C.; (3) providing a volume of a solution comprising metallocene and alumoxane wherein the volume of solution is less than that required to form a slurry of the silica, wherein the concentration of alumoxane, expressed as Al weight percent, is 5 to 20; (4) contacting the silica slurry (2) with said volume of said solution (3) and allowing the solution to impregnate the pores of silica and, to disperse the metallocene in and on the carrier; (5) evaporating the solvents from the contacted and impregnated silica to recover dry free-flowing catalyst particles.

Abstract: The invention relates to a process for the manufacture of a solid catalytic component for the polymerization or copolymerization of olefins, resulting in a polymer or copolymer with broadened molecular mass distribution. The process includes a first stage including bringing into contact a) a solid support including at its surface at least 5 hydroxyl groups per square nanometre (OH/nm2) and b) an organic magnesium derivative, and optionally, preferably, c) an aluminoxane, to obtain a first solid, and then a second stage including bringing the first solid and a chlorinating agent into contact to obtain a second solid and then, in a later stage, impregnation of the second solid with a transition metal derivative.

Abstract: The olefin polymerization catalyst comprises a supported transition metal, magnesium and halogen; the support comprises aluminum phosphate and at least one oxide of silica or alumina. The catalyst is formed by impregnating the support with a liquid complex formed by reacting a magnesium compound and a transition metal compound, which can contain either oxygen or halogen, and then precipitating the complex on the support with an organoaluminum compound which may be halogenated. The catalyst is used with an organometallic cocatalyst.

Abstract: The present invention provides a Ziegler-Natta catalyst useful in solution processes for the polymerization of olefins having a low amount of aluminum and magnesium. The catalysts of the present invention have a molar ratio of magnesium to the first aluminum component from 4.0:1 to 5.5:1 and molar ratio of magnesium to transition metal from 4.0:1 to 5.5:1.

Abstract: Described are an aluminum compound-containing solid catalyst component obtained by bringing a carrier into contact with an organoaluminumoxy compound, followed by bringing this product into contact with a compound having an electron attractive group; a transition metal-containing solid catalyst component obtained by bringing the aluminum compound-containing solid catalyst component into contact with a transition metal compound; a catalyst for olefin polymerization, constituting the aluminum compound-containing solid catalyst component and an organoaluminum compound; and a method for producing an olefin polymer, which includes polymerizing or copolymerizing an olefin using the catalyst for olefin polymerization.

Abstract: Disclosed is a catalyst for olefin (co-)polymerization comprising a transition metal compound catalytic component which contains at least a titanium compound and an &agr;-olefin (co-)polymer (A) supported by the catalyst, wherein said &agr;-olefin (co-)polymer (A) has an intrinsic viscosity (&eegr;) of 15 dl/g to 100 dl/g measured in tetrahydronaphthalene at 135° C., and the content of said olefin (co-)polymer (a) is 0.01 to 5000 g for 1 g of the transition compound catalytic component.

Abstract: Provided are a propylene-ethylene block copolymer having MFR of from 0.01 to 1.0 g/10 min and comprised of (A) from 85 to 97% by weight a 25° C. xylene-insoluble fraction and (B) from 3 to 15% by weight of a 25° C. xylene-soluble fraction, wherein the fraction (A) is such that its stereospecificity index measured through 13C-NMR is at least 98.0%, its intrinsic viscosity [&eegr;] falls between 2.5 and 5.5 dl/g, and its weight-average molecular weight, Mw, measured through GPC and the content, S, of the fraction having a molecular weight of at most 104.5 therein satisfy S (wt. %)≦−5.3×10−6 Mw+7.58, and the fraction (B) is such that its ethylene unit content measured through 13C-NMR falls between 30 and 70% by weight, and its intrinsic viscosity [&eegr;] falls between 2.5 and 9.0 dl/g; and its blow-molded articles.

Abstract: The present invention relates to a method of polymerization or co-polymerization of olefin under the catalyst system which comprises (a) a solid complex titanium catalyst comprising of a magnesium compound, a titanium compound, and an internal electron donor; (b) an organometallic compound of metal of Group I or Group III on the Periodic Table; and (c) two of external electron donors comprising an external electron donor (1) and an external electron donor (2), wherein the ratio of the MFR (1) to the MFR (2) is 2˜10, the MFR (1) being that of the homopolymer (1) obtained by using said external electron donor (1) with said solid complex titanium catalyst (a) and the organometallic compound (b), and the MFR (2) being that of the homopolymer (2) obtained by using said external electron donor (2) under the identical polymerization reaction conditions of said external electron donor (1), and wherein the NMR pentads of the homopolymer (1) and the homopolymer (2), respectively, are 95.5% or more.

Abstract: Propylene-ethylene copolymers obtainable by three-step polymerization from the gas phase in an agitated fixed bed by means of a Ziegler-Natta catalyst system which, in addition to a titanium-containing solid component, also contains, as cocatalyst, an aluminum compound, where, in a first polymerization step, propylene is polymerized at from 60 to 90° C. and at from 20 to 40 bar and at a mean residence time of the reaction mixture of from 0.5 to 5 hours, then, in a second polymerization step, a mixture of propylene and ethylene is polymerized onto the polymer obtained from the first polymerization step at from 40 to 110° C. and from 5 to 30 bar, this pressure being at least 7 bar below the pressure in the first polymerization step, and at a mean residence time of the reaction mixture of from 0.2 to 4 hours, and then, in a third polymerization step, ethylene or a mixture of ethylene and propylene is polymerized onto the polymer obtained from the second polymerization step at from 40 to 110° C.

Abstract: An ethylene-alpha-olefin copolymerization catalyst is prepared by impregnating a silica calcined at elevated temperature sequentially with an organomagnesium compound such as dialkylmagnesium compound, a silane compound which is free of hydroxyl groups, such as tetraethyl orthosilicate. A transition metal component such as titanium tetrachloride is then incorporated into the support. Unexpectedly, the calcination temperature of the silica used to prepare the catalyst precursors has a strong influence on polymer product properties. By increasing the calcination temperature of the silica from 600° to 700° C. or higher temperatures, a catalyst precursor when activated produced ethylene/1-hexene copolymers with narrower molecular weight distributions (MWD) as manifested by a decrease of resin MFR values of ˜3-4 units. Activation of this catalyst precursor with a trialkylaluminum compound results in a catalyst system which is effective for the production of ethylene copolymers.

Abstract: In the polymerization of C3-C12-&agr;-olefins, the activity of the catalyst and the isotacticity and molecular weight of the polymer product can be adjusted and improved in a controlled manner by a new process wherein A) a catalyst system is prepared by bringing a support which comprises magnesium chloride, a derivative thereof or a reagent forming it into contact with at least titanium tetrachloride or a reagent forming it, in order to produce a titanated support; by bringing the titanated support into contact with at least a group 1, 2 or 13 metal compound which contains a C1-C10-alkyl and activates titanium tetrachloride to a catalytically active titanium group, in order to produce an activated support; and by bringing a substance selected from among the said support, titanated support and activated support into contact with at least one donor or a reagent forming it, in order to produce a catalyst system B) polymerization is carried out using the catalyst system by bringing it into contact with at least

Abstract: An olefin (co-)polymer composition including 0.01 to 5.0 weight parts of high molecular weight polyethylene which is an ethylene homopolymer or an ethylene-olefin copolymer containing 50 weight % or more of an ethylene polymerization unit; and 100 weight parts of an olefin (co-)polymer other than the high molecular weight polyethylene, wherein said high molecular weight polyethylene has an intrinsic viscosity [&eegr;E] of 15 to 100 dl/g measured in tetralin at 135° C. or more, and said high molecular weight polyethylene exists as dispersed fine particles having a numerical average particle size of 1 to 5000 nm.

Abstract: A procatalyst and a process for the preparation of a multimodal ethylene homopolymer or copolymer by gas-phase polymerisation is described. The procatalyst used in the process is prepared by: a) contacting the support, preferably silica with a halogenating agent, preferably ethyl aluminium dichloride to obtain a first reaction product, b) contacting the first reaction product with a compound or mixture containing hydrocarbyl and one or more of hydrocarbyloxy, monoalkylamido, dialkylamido, carboxylato and alkoxymethoxy groups linked to magnesium, thereby to obtain a second reaction product (the procatalyst precursor), and c) contacting the second reaction product with a titanium compound, preferably TiCl4. In step a) the molar ratio of the alkyl metal chloride to the surface hydroxyls of the inorganic oxide is preferably between 1:1 and 10:1. In step b) the atomic ratio of the magnesium to the chlorine of the alkyl metal chloride of step a) preferably is between 1:1.5 to 1:2.5.