Abstract: A process for polymerizing ethylene comprising contacting under polymerization condition ethylene and optionally one or more olefins with a catalyst system obtainable by contacting: a bis amido compound of formula (I) wherein Y is Si, Ge and Sn; X is hydrogen, halogen or an hydrocarbon radical; R1, R2, R3, R4, R5 and R6, are hydrocarbon radical; Q is a neutral Lewis base; and m is 0–2; one or more boron activating cocatalysts and one or more aluminum alkyls or alumoxanes.

Abstract: The present invention relates to a process for the preparation random copolymers of butadiene and isoprene, essentially consisting of reacting a catalytic system in the presence of butadiene and isoprene and using, as catalytic system, a system based on at least:—a conjugated diene monomer,—an organic phosphoric acid salt of one or more rare earth metals,—an alkylating agent consisting of an alkylaluminium of the formula AlR3 or HAlR2, and—a halogen donor consisting of an alkylaluminium halide, said salt being in suspension in at least one inert, saturated and aliphatic or alicyclic hydrocarbon solvent, which is included in said catalytic system, and the “alkylating agent:rare earth salt” molar ratio falls within a range of from 1 to 8, and performing the copolymerization reaction in an inert hydrocarbon polymerisation solvent or without solvent. These copolymers are in particular such that the butadiene and isoprene units which they comprise each have an elevated content of cis-1,4 linkages.

Abstract: A process is described for obtaining from an “FCC” initial C5 fraction which is enriched with isoprene and purified and usable for the selective polymerization of isoprene. A process is also described for obtaining an isoprene homopolymer from a polymerization medium comprising isoprene and at least one methyl butene, such as said “FCC” C5 fraction which is enriched with isoprene and purified. The process of obtaining the final fraction from the initial C5 fraction includes: a catalytic hydrogenation reaction of said initial C5 fraction by a palladium-based catalyst, which produces an intermediate C5 fraction comprising n-pentenes in a mass ratio which is less than 0.

Abstract: The present invention relates to a method for preparing neodymium-carbon-nanotube and a process for preparing 1,4-cis-polybutadiene utilizing the same and more particularly, neodymium-carbon-nanotube. Neodymium is introduced by coordination with carboxylic acid, which is formed on the surface of carbon nanotube. In 1,3-butadiene polymerization with the neodymium-catalyst comprising the neodymium-carbon nanotube, a particular halogen compound, and a particular organometallic compound in an appropriate ratio, high 1,4-cis polybutadiene having molecular weight of 10,000 to 2,000,000 is produced, which exhibits excellent mechanical properties such as elasticity and durability.

Abstract: The present invention relates to a process for the preparation random copolymers of butadiene and isoprene, essentially consisting of reacting a catalytic system in the presence of butadiene and isoprene and using, as catalytic system, a system based on at least:—a conjugated diene monomer,—an organic phosphoric acid salt of one or more rare earth metals,—an alkylating agent consisting of an alkylaluminium of the formula AlR3 or HAlR2, and—a halogen donor consisting of an alkylaluminium halide, said salt being in suspension in at least one inert, saturated and aliphatic or alicyclic hydrocarbon solvent, which is included in said catalytic system, and the “alkylating agent:rare earth salt” molar ratio falls within a range of from 1 to 8, and performing the copolymerisation reaction in an inert hydrocarbon polymerisation solvent or without solvent. These copolymers are in particular such that the butadiene and isoprene units which they comprise each have an elevated content of cis-1,4 linkages.

Abstract: The invention relates to a chemical compound of formula (I), wherein M1 represents an element selected from main groups II, III or IV of the periodic table of elements; x is equal to 1, 2, 3 or 4; y is equal to 2, 3 or 4, and; A represents a cation of main group V of the periodic table of elements; R1 is the same or different and represents a branched or unbranched linear or cyclic C1–C40 group that contains carbon; R2 is the same or different and represents a branched or unbranched linear or cyclic C1–C40 group that contains carbon; R3 represents a branched or unbranched linear or cyclic C1–C40 group that contains carbon, and; R4 represents a hydrogen atom; whereby R2 and R3 are always different from one another

Abstract: A process is described for the preparation of polydienes with a low vinyl content and having a branched structure effected by means of the polymerization of conjugated dienes in the presence of catalysts based on rare-earth compounds. The resulting polymers are characterized in that they have a cis content varying from 80 to 96% and prove to be branched with consequent low viscosity values in solution.

Abstract: The present invention relates to a catalyst composition for polymerization of a conjugated diene, comprising: (A) a metallocene-type complex represented by a general formula (I): (C5R1R2R3R4R5)aMXb.Lc (where, M represents a rare earth metal; C5R1R2R3R4R5 represents a substituted cyclopentadienyl group; R1 to R5 represent the same or different hydrocarbon groups (except when R1=R2=R3=R4=R5=a methyl group); X represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group, or a hydrocarbon group having 1 to 20 carbon atoms; L represents a Lewis basic compound; “a” represents an integer of 1, 2, or 3; “b” represents an integer of 0, 1, or 2; and “c” represents an integer of 0, 1, or 2); and (B) an ionic compound composed of a non-coordinating anion and a cation, and/or an aluminoxane.

Abstract: The present invention relates to a catalytic system usable for the preparation of polybutadienes by polymerisation, to a process for the preparation of said catalytic system and to a process for the preparation of polybutadienes by means of this catalytic system. A catalytic system according to the invention is based on at least: a conjugated diene monomer, an organic phosphoric acid salt of one or more rare earth metals, said salt being in suspension in at least one inert, saturated and aliphatic or alicyclic hydrocarbon solvent, an alkylating agent consisting of an alkylaluminium of formula AlR3 or HAlR2, the “alkylating agent:rare earth salt” molar ratio being greater than 5, and a halogen donor which belongs to the family of alkylaluminium halides with the exception of alkylaluminium sesquihalides, and, according to the invention, said catalytic system comprises said rare earth metal(s) in a concentration equal to or greater than 0.005 mol/l.

Abstract: Catalyst systems and methods for olefin polymerization are disclosed. The polymerizations are performed in the presence of a clathrochelate which comprises a transition metal ion and an encapsulating macropolycyclic ligand. At least one of the capping atoms of the macropolycyclic ligand is a Group 3–10 transition metal or a Group 13 atom. When a capping atom is a Group 3–10 transition metal, the clathrochelate can be used with an activator to polymerize olefins. When a capping atom is a Group 13 atom, the clathrachelate can be used as an activator for an olefin polumerization. Clathrochelates allow polyolefin markers to fine tune catalyst reactivity and polyolefin properties.

Abstract: A process for polymerizing an olefin is capable of polymerizing an olefin with excellent polymerization activity, and comprises polymerizing or copolymerizing an olefin at a polymerization reaction temperature of 50 to 200° C. in the presence of a catalyst comprising a transition metal compound (A) represented by the following formula (I), a compound (B-1) having a reduction ability which reacts with the transition metal compound (A) to convert an imine structure moiety to a metal amide structure, and a compound (B-2) which reacts with the transition metal compound (A) to form an ion pair; wherein M is a transition metal atom of Groups 3 to 11 of the periodic table; m is an integer of 1 to 6; Y is O, S, Se, or —C(R7)—; R1 to R7 may be the same or different, and are each a hydrogen atom, a halogen atom, a hydrocarbon group, an oxgen-containing group, a nitrogen-containing group and the like; n is a number satisfying a valence of M; and X is a hydrogen atom, a halogen atom, a hydrocarbon group and the like.

Abstract: Films and methods of forming films comprising first combining in a reactor olefins, a catalyst composition and an activator; wherein the activator is present from less than 50 wt % in a diluent by weight of the activator and diluent; followed by isolating a polyolefin having a density of from 0.940 to 0.980 g/cm3; and finally, extruding the polyolefin into a film having a gel count of less than 200 gels/m2.

Abstract: The present invention provides synthetic polyisoprenes having a high cis-1,4 linkage content and a process for their preparation. The synthetic polyisoprenes according to the invention have a cis-1,4 linkage content, measured by carbon-13 nuclear magnetic resonance and/or medium-wave infrared radiation analysis, of greater than 99.0%. The process for the preparation of these synthetic polyisoprenes involve polymerizing, at a temperature of 0° C. or lower, isoprene in the presence of a catalytic system based on: a) a conjugated diene monomer, b) an organic phosphoric acid salt of one or more rare earth, c) an alkylaluminium alkylating agent of the formula AlR3 or HAlR2, and d) a halogen donor consisting of an alkylaluminium halide, wherein the salt is suspended in at least one inert, saturated aliphatic or alicyclic hydrocarbon solvent and the alkylating agent:rare earth salt molar ratio ranges from 1 to 5.

Abstract: Single-site catalyst systems useful for polymerizing olefins are disclosed. The catalyst systems comprise an organometallic complex and an activator. The complex includes a Group 3-10 transition metal, M, and at least one indenoindolyl ligand that is pi-bonded to M. The activator is a reaction product of an alkylaluminum compound and an organoboronic acid. Catalyst systems of the invention significantly outperform known catalyst systems that employ a metallocene complex and similar aluminoboronate activators.

Abstract: A method for making ethylene polymers and copolymers is disclosed. The method uses a catalyst system comprising a low level of an aluminum-containing activator, a bridged indenoindolyl transition metal complex, and a treated silica support. The method enables economical preparation of ethylene copolymers having very low density. The silica-supported, bridged complexes incorporate comonomers efficiently and are valuable for a commercial slurry loop process. Use of a bridged indeno[2,1-b]indolyl complex provides exceptionally efficient comonomer incorporation, and gives polymers with a substantial and controlled level of long-chain branching. The method facilitates the production of a wide variety of polyolefins, from HDPE to plastomers.

Abstract: A propylenic polymer according to the present invention or a composition thereof have an excellent melt flowability and contains a less amount of stickiness-causing components, and also has a low modulus and is pliable, and is capable of providing a transparent molded article, thus being useful as a substitute for a pliable vinyl chloride resin. In addition, a molded article made therefrom exhibits an excellent heat seal performance at a low temperature, and is excellent in terms of transparency and rigidity. Specifically, it has an isotactic pentad fraction (mmmm), which indicates a stereoregulariry, of 30 to 80%, a molecular weight distribution (Mw/Mn) of 3.5 or less and an intrinsic viscosity [?] of 0.8 to 5 dl/g.

Abstract: Ethylene and optional comonomers are polymerized using a supported metallocene catalyst, an alumoxane activator, and triisobutylaluminum (TIBAL). A silica support is first pretreated with a silane compound and then with an organoboron compound. The treated silica is then combined with a Group 4 metallocene complex and an alumoxane to generate a supported, activated catalyst. While it was previously thought that the particular support treatment technique used herein provided benefits only for polymerizations catalyzed by non-metallocene single-site complexes, it has now been found that similar benefits can be realized even with conventional metallocenes if TIBAL is selected as the scavenger.

Abstract: A catalyst system suitable for use in the production of high cis polybutadiene is disclosed. The catalyst system includes a cobalt salt of the formulaCoAx?, where A is a monovalent or divalent anion and x is 1 or 2; an alkyl aluminum chloride compound of the structure R2AlCl, where R is an alkyl group containing 2-8 carbon atoms; a trialkyl aluminum compound of the formula R3Al, where R is an alkyl group containing 2-8 carbon atoms; and a catalytic amount of water.

Abstract: A catalyst for addition polymerization obtained by bringing the following (A) into contact with (B) a specific organic aluminum compound and/or aluminoxane, and (C) a specific boron compound, and a process for producing an addition polymer with the same.

Abstract: A process for preparing syndiotactic polymers of vinylaromatic monomers having improved melt flowability comprising contacting one or more vinylaromatic monomers with a catalyst system comprising a titanium coordination complex capable of preparing syndiotactic vinylaromatic polymers under addition polymerization conditions in the presence of hydrogen gas at a hydrogen partial pressure from 0.1 to less than 10 kPa.

Abstract: The present invention relates to a process for obtaining a polyisoprene having a high cis-1,4 linkage content, from a steam-cracked C5 naphtha fraction enriched with isoprene. The process of the present invention comprises reacting a steam-cracked C5 naphtha fraction in the presence of a catalytic system, wherein the C5 fraction is enriched with isoprene such that the mass fraction of isoprene in said enriched fraction lies within a range of from 30% to 95%, and the catalytic system is based on at least (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of one or more rare earth metals, (c) an alkylating agent consisting of an alkylaluminum of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminum halide, said salt being suspended in at least one inert saturated hydrocarbon solvent of aliphatic or alicyclic type which is included in said catalytic system, and the molar ratio of alkylating agent:rare earth salt is in a range of from 1 to 5.

Abstract: The present invention provides a catalytic system that can be used to prepare by polymerization diene elastomers comprising polyisoprenes and polybutadienes. The invention also provides a process for the preparation of the catalytic system and to a process using the catalytic system to prepare diene elastomers comprising polyisoprenes having a high cis-1,4 linkage content and polybutadienes. The catalytic system according to the invention is based on (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of a rare earth metal, (c) an alkylating agent consisting of an alkylaluminium of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminium halide, and is such that said salt is suspended in at least one inert and saturated aliphatic or alicyclic hydrocarbon solvent and, the “alkylating agent:rare earth salt” molar ratio ranges from 1 to 5.

Abstract: It has been discovered that using di-sec-butyldialkoxysilanes, such as di-sec-butyldimethoxysilane (DSBDMS), as external electron donors for Ziegler-Natta catalysts can provide a catalyst system that may prepare polypropylene films with improved properties and processing. The catalyst systems of the invention provide high activity, high bulk density, moderate hydrogen response, moderate donor response and high polydispersity (MWD). Suitable di-sec-butyldialkoxysilanes have the formula (SBu)2Si(OR″)2, where R″ is independently a straight or branched alkyl group of 1-5 carbon atoms.

Abstract: A catalyst for olefin polymerization, comprising:

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: Provided are catalysts for styrene polymerization capable of efficiently and inexpensively producing styrenic polymers having a syndiotactic structure; and a method for producing styrenic polymers. The catalysts comprise (A) a transition metal compound, (B) an oxygen-containing compound and/or a compound capable of reacting with a transition metal compound to form an ionic complex, (C) a specific metal compound, preferably a specific organoaluminium compound of a general formula: ((R1)3—CO)n-Al—(R2)3−n wherein R1 represents an aliphatic hydrocarbon group having from 1 to 30 carbon atoms, an aromatic hydrocarbon group having from 6 to 30 carbon atoms or the like; R2 represents a hydrocarbon group; n is 1 or 2, and optionally (D) an alkylating agent. In the method for producing styrenic polymers, used is the catalyst.

Abstract: The present invention relates to a process for polymerizing olefin(s) in the presence of metallocene-type catalyst compound, an activator and an inorganic oxide support, a Group 13 containing compound and a carboxylic acid, where the carboxylic acid is added to the polymerization reactor separately. The invention also relates to a process for transitioning from one polymerization catalyst to another.

Abstract: A process for producing a polymer, which comprises polymerizing a vinyl compound (I) represented by the general formula CH2═CH—R, wherein steric parameters Es and B1 of the substituent R are respectively −1.64 or less and 1.53 or more, or a vinyl compound (II) represented by the general formula CH2═CH—R′, wherein a substituent R′ is a secondary or tertiary alkyl group, in the presence of a catalyst obtained by combining: (A) a transition metal compound represented by the general formula [1] (B) an organoaluminum compound and (C) a boron compound.

Abstract: A process for preparing olefinic living polymers having a molecular weight distribution (Mw/Mn) of 1 to 1.3, comprising polymerizing an olefinic monomer having 2 to 20 carbon atoms at low temperatures in the presence of a catalyst comprising (A) a hafnium or zirconium-containing compound having one or two cyclopentadienyl backbones, (B) a triphenyl boron compound or a tetraphenyl borate compound and optionally (C) a specific mono-, di- or trialkylaluminum compound. When the catalyst comprising the zirconium-containing compound is prepared by further using a titanium-containing compound (D), the polymerization temperature can be raised.

Abstract: A solution polymerization process using a phosphinimine catalyst and a boron activator is conducted at a temperature of about 170° C. or greater in the presence of trialkyl aluminum to produce polyethylene having a comparatively broad molecular weight distribution. The polyethylene product produced by the process of this invention is desirable because it can provide enhanced “processability” in comparison to polyethylene having a narrow molecular weight distribution. The process of this invention is advantageous in comparison to prior art processes for the preparation of “broad” polyethylene which use two polymerization reactors and/or more than one polymerization catalyst. The polymers produced by the process of this invention are potentially suitable for the preparation of plastic film. For example, a polyethylene according to this invention and having a density of about 0.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components: (A) a porous organic support functionalised with groups having active hydrogen atoms; (B) an organo-metallic compound of aluminium containing heteroatoms selected from oxygen, nitrogen and sulphur; and (C) a compound of a transition metal selected from those of groups IVb, Vb or VIb of the Periodic Table of the Elements, containing ligands of the cyclopentadienyl type. These supported catalysts, obtainable in the form of spherical particles, can be used in the polymerization reaction of olefins either in liquid or in gas phase, thus producing polymers endowed with a controlled morphology and with a high bulk density.

Abstract: An olefin polymerization process is disclosed. The process comprises polymerizing olefins in the presence of a supported indenoindolyl catalyst system and an organoboron or organoaluminum-treated solid. The supported indenoindolyl catalyst system comprises a support, an organometallic complex comprising a Group 3 to 10 transition or lanthanide metal, M, and at least one indenoindolyl ligand that is &pgr;-bonded to M, and an activator. Performing the process in the presence of the organoboron or organoaluminum-treated solid surprisingly leads to an increased activity compared to polymerization processes performed without the treated solid.

Abstract: Prealkylation of a supported catalyst system comprising a transition metal or inner transition metal complex precatalyst and a bulky, non-coordinating anion on an inorganic support by treatment with a solution of metal alkyl in a ratio of metal of metal alkyl to transition metal or inner transition metal of precatalyst less than 20:1, and in an amount of solution insufficient to form a paste or dispersion provides supported catalysts of high olefin polymerization activity which promote production of polyolefins of low polydispersity and improved morphology.

Abstract: The present invention is a polar group-containing olefin copolymer having excellent adhesion properties to metals or polar resins and excellent compatibility therewith. A process for preparing the copolymer, a thermoplastic resin composition containing the copolymer, and uses thereof are also described. The polar group-containing olefin copolymer comprises a constituent unit derived from an &agr;-olefin of 2 to 20 carbon atoms, and a constituent unit derived from a straight-chain, branched or cyclic polar group-containing monomer having at the end a polar group such as a hydroxyl group or an epoxy group and/or a constituent unit derived from a macromonomer having at the end a polymer segment obtained by anionic polymerization, ring-opening polymerization or polycondensation.

Abstract: A supported catalyst for olefin polymerization comprises a combination of a novel metal oxide support and an activator which is an aluminoxane or a boron activator. The novel metal oxide support of this invention is a conventional particulate metal oxide support material (such as silica or alumina) which has been treated with a halosulfonic acid. A catalyst system which contains this novel catalyst support and a transition metal catalyst is highly active for olefin polymerization (in comparison to prior art catalyst systems which use a conventional metal oxide support).

Abstract: Alumoxanes having C2-C12 alkyl groups can conveniently be used in supported olefin polymerization catalyst compositions prepared by contacting, either previous to or immediately before the beginning of the olefin polymerization, a support comprising a porous carrier with (a) an organometallic compound of the general formula R1MXv−1, (b) a metallocene of the general formula (CpY)mM′X′nZo and an alumoxane of the following general formula in any order.

Abstract: Catalyst system for the polymerization of olefins CH2═CHR, wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, comprising the product of the reaction between (a) a solid catalyst component comprising Mg, Ti, and halogen, (b) dimethylaluminium chloride (DMAC) and (c) an alkylaluinium compound, in which the molar ratio between (b) and (c) is lower than 10. This kind of catalyst system is particularly suitable for the preparation of copolymers of ethylene with &agr;-olefins due to its high capacity for incorporating the comonomer while at the same time maintaining high yields.

Abstract: A catalyst system suitable for use in the production of high cis polybutadiene is disclosed. The catalyst system includes a cobalt salt of the formulaCoAx?, where A is a monovalent or divalent anion and x is 1 or 2; an alkyl aluminum chloride compound of the structure R2AlCl, where R is an alkyl group containing 2-8 carbon atoms; a trialkyl aluminum compound of the formula R3Al, where R is an alkyl group containing 2-8 carbon atoms; and a catalytic amount of water.

Abstract: The present invention provides a catalyst component used for homopolymerization or co-polymerization of ethylene, comprising at least one suitable electron donor compound supported on a composition containing magnesium and titanium, wherein the electron donor compound is selected from the group consisting of aliphatic ethers, alicyclic ethers, aromatic ethers, aliphatic ketones and alicyclic ketones, and wherein the composition containing magnesium and titanium is prepared by dissolving a magnesium compound into a solvent system to form a homogeneous solution and then contacting the solution with a titanium compound in the presence of a precipitation aid to precipitate the composition. The present invention also relates to a method for the preparation of said catalyst component and a catalyst comprising thereof, and to use of the catalyst in homopolymerization of ethylene or co-polymerization of ethylene with at least one C3-C8 &agr;-olefln.

Abstract: The present invention provides a catalytic system that can be used to prepare by polymerization diene elastomers comprising polyisoprenes and polybutadienes. The invention also provides a process for the preparation of the catalytic system and to a process using the catalytic system to prepare diene elastomers comprising polyisoprenes having a high cis-1,4 linkage content and polybutadienes. The catalytic system according to the invention is based on (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of a rare earth metal, (c) an alkylating agent consisting of an alkylaluminium of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminium halide, and is such that said salt is suspended in at least one inert and saturated aliphatic or alicyclic hydrocarbon solvent and, the “alkylating agent:rare earth salt” molar ratio ranges from 1 to 5.

Abstract: Prealkylation of a supported catalyst system comprising a transition metal or inner transition metal complex precatalyst and a bulky, non-coordinating anion on an inorganic support by treatment with a solution of metal alkyl in a ratio of metal of metal alkyl to transition metal or inner transition metal of precatalyst less than 20:1, and in an amount of solution insufficient to form a paste or dispersion provides supported catalysts of high olefin polymerization activity which promote production of polyolefins of low polydispersity and improved morphology.

Abstract: A butadiene polymer (i) having a cis bond unit content of at least 50% based on the total butadiene units, a number average molecular weight (Mn) of 1,000 to 10,000,000, and at least 80%, based on the total molecular chains, of living chains containing a transition metal of group IV of the Periodic table at a terminal thereof; a polymer (ii) obtained by modifying terminals of the polymer (i); and a polymer (iii) obtained by coupling the polymers (i). These polymers (i), (ii) and (iii) are obtained by polymerizing a conjugated diene monomer alone or with a copolymerizable monomer at a specific temperature in the presence of a catalyst comprising a compound (A) of a transition metal of group IV of the periodic table having a cyclopentadienyl structure and a co-catalyst (B) selected from organoaluminum-oxy compound (a) and others and optionally further by contacting the resultant polymer with a terminal modifier or a coupling agent.

Abstract: The present invention relates to a process for obtaining a polyisoprene having a high cis-1,4 linkage content, from a steam-cracked C5 naphtha fraction enriched with isoprene. The process of the present invention comprises reacting a steam-cracked C5 naphtha fraction in the presence of a catalytic system, wherein the C5 fraction is enriched with isoprene such that the mass fraction of isoprene in said enriched fraction lies within a range of from 30% to 95%, and the catalytic system is based on at least (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of one or more rare earth metals, (c) an alkylating agent consisting of an alkylaluminum of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminum halide, said salt being suspended in at least one inert saturated hydrocarbon solvent of aliphatic or alicyclic type which is included in said catalytic system, and the molar ratio of alkylating agent: rare earth salt is in a range of from 1 to 5.

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: A process for production of an olefin polymer is provided which comprises polymerization of ethylene and/or &agr;-olefin of three of more carbons at a polymerization temperature of not lower than 120° C. with a catalyst comprising a specific metallocene compound having a substituted fluorenyl group, and a compound which reacts with the metallocene compound to form a cationic metallocene compound. The olefin polymer or copolymer produced by the process has narrow composition distribution, narrow molecular weight distribution, and a high molecular weight.

Abstract: An olefin polymerization catalyst is provided which makes use of a modified methylaluminoxane and thus stably exhibits an activity equivalent to, or higher than, the activity achieved by polymethylaluminoxane.

Abstract: Catalyst solid for olefin polymerization comprising

Abstract: A process of polymerizing ethylene or ethylene and one or more comonomers in one or more fluidized bed reactors with a catalyst system comprising (i) a supported or unsupported magnesium/titanium based precursor in slurry form, said precursor containing an electron donor; and (ii) an activator containing aluminum in an amount sufficient to essentially complete the activation of the precursor is disclosed. In the process, the precursor and the activator are mixed prior to introduction into the reactor in at least one mixing procedure, and then the mixture is contacted again with additional activator to essentially complete activation of the precursor. In the method, the atomic ratio of aluminum to titanium is in the range of about 1:1 to about 15:1 and the mole ratio of activator to electron donor is about 1:1 to about 2:1, and no additional activator is introduced into the reactor(s).

Abstract: Process for polymerising alpha-olefins in which at least one alpha-olefin is placed in contact, in polymerising conditions, with a catalytic system comprising at least one catalytic complex (a) based on a metal (M) of groups 6 to 12 of the Periodic Table, at least one trialkylaluminium (b) corresponding to the general formula AIR3, in which each R represents, independently, a linear alkyl group containing from 1 to 30 carbon atoms, at least one trialkylaluminium (c) corresponding to the general formula AIR′3, in which each R′ represents, independently, a branched alkyl group containing from 3 to 30 carbon atoms, such that the molar ratio of trialkylaluminium (c) to trialkylaluminium (b) is at least 2.

Abstract: The process is characterized by the use of catalyst systems consisting of a single metallocene catalyst activated with mixtures of at least 2 co-catalysts. The co-catalysts are aluminium alkyls, aluminoxanes or boron compounds. Different active centers are produced in the catalyst through the use of these mixed co-catalyst systems, each having different rates of initiation and completion of the polymerization reaction, which give rise to polyolefins with different molecular weights, resulting in products with broad bimodal or multimodal molecular weight distributions and the incorporation of co-monomer can be controlled by appropriate selection of the metallocene and use of combinations of different types of co-catalysts, as well as by varying the reactor pressure, the reaction temperature and the molar ratios between the various components of the catalyst system.