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: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The metallocene compositions may be represented by the formula: wherein R3 are identical or different and are each a halogen atom, a C1-C10 alkyl group which may be halogenated, a C6-C10 aryl group which may be halogenated, a C2-C10 alkenyl group, a C7-C40-arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, a —NR?2, —SR?, —OR?, —OSiR?3 or —PR?2 radical, wherein R? is one of a halogen atom, a C1-C10 alkyl group, or a C6-C10 aryl group, and R9 and R11 are identical or different and are a Group 14 radical having from 1 to 20 carbon atoms or are each primary, secondary or tertiary butyl groups, aryl groups, isopropyl groups, fluoroalkyl groups, trialkyl silyl groups, or other groups of similar size.

Abstract: A process for purifying metallocenes in which a sparingly soluble metallocene halide is converted into a readily soluble and readily crystallizable metallocene by replacement of at least one halide ligand by an alternative negatively charged ligand and the metallocene obtained in this way is subsequently purified by crystallization.

Abstract: A transition metal catalyst component for polymerization, composed of a metal complex comprising specific ligands and a specific substituted boron group and having a bridging group, which exhibits a very high activity for an olefin type (co)polymerization or an olefin-aromatic vinyl compound copolymerization, whereby the molecular weight of a copolymer obtainable, is high. A method for producing an olefin (co)polymer and an aromatic vinyl compound-olefin copolymer, by means thereof.

Abstract: This invention relates to bridged indenyl metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The bridge may be represented by the formula: wherein: R17 to R24 are identical or different, and are one of a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C2-C10 alkenyl group, a C7-C40 arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, or a halogen atom, or together are a conjugated diene which is optionally substituted with one or more hydrocarbyl, tri(hydrocarbyl)silyl groups or hydrocarbyl, tri(hydrocarbyl)silylhydrocarbyl groups, said diene having up to 30 atoms not counting hydrogen; or two or more adjacent radicals R17 to R24, including R20 and R21, together with the atoms connecting them form one or more rings; and M2 is carbon, silicon, germanium or tin.

Abstract: Process for the polymerization of olefins comprising contacting olefins under polymerization conditions in the presence of a catalyst system comprising the product obtained by contacting: (A) at least one transition metal organometallic compound, pyrolidyl bis(?-cyclopentadienyl)methylzirconium being excluded, and (B) an organometallic compound obtained by contacting: (a) a Lewis base having formula (I): ?wherein Ra, Rb, Rc and Rd, equal to or different from each other, are selected from the group consisting of hydrogen, halogen, linear or branched, saturated or unsaturated, C1-C10 alkyl, C6-C20 aryl, C7-C20 arylalkyl and C7-C20 alkylaryl groups; with b) a Lewis acid of formula (II) MtR13??(II) ?wherein Mt is a metal belonging to Group 13 of the Periodic Table of the Elements; R1, equal to or different from each other, are selected from the group consisting of halogen, halogenated C6-C20 aryl and halogenated C7-C20 alkylaryl groups; and (C) optionally an alkylating agent.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system comprises an activator and an organometallic complex that incorporates a Group 3 to 10 transition metal and at least one chelating, dianionic triquinane ligand. The cis,syn,cis-triquinane framework is generated in three high-yield steps from inexpensive starting materials, and with heat and light as the only reagents. By modifying substituents on the triquinane ligand, polyolefin makers can control catalyst activity, comonomer incorporation, and polymer properties.

Abstract: The invention relates to a method for producing special transition metal compounds, to novel transition metal compounds and to the use of the same for the polymerisation of olefins.

Abstract: A complex of a Group 3-10 metal, said complex comprising a cyclic group containing delocalized electrons, a bridging group connecting he metal with the cyclic group, and acetylene or a derivative thereof.

Abstract: The present invention provides a method of synthesizing fluorided metallocene catalyst components comprising contacting at least one fluoriding agent comprising fluorine with one or more alkylated metallocene catalyst components comprising one or more non-halogen leaving groups to produce a fluorided catalyst component; wherein from less than 3 equivalents of fluorine are contacted for every equivalent of leaving group. The method of the invention is exemplified by the following reaction which takes place in a non-coordinating diluent such as pentane: wherein one or both of the “Cp” rings may be substituted with an R group as described herein, and may be bridged. The reaction can be run at any desirable temperature, desirably between 10° C. and 35° C. The reaction product of the BF3 and dimethyl zirconocene is the fluorided zirconocene. The mole ratio of the BF3 fluoriding agent and the starting metallocene is less than 2:1 (fluoriding agent:metallocene) in one embodiment, and less than or equal to 1.

Abstract: Ethylene based polymers having high molecular weights can be obtained in high yields at temperatures of industrial interest, by carrying out the polymerization reaction in the presence of catalysts comprising single carbon bridged metallocenes, which has a particular ligand system containing a heteroatom.

Abstract: A process is described for the preparation of elastomeric EP(D)M copolymers and terpolymers, characterized in that it is carried out in the presence of metallocene compounds of general formula (I) having a racemic stereoisomerism

Abstract: Supported metallocene catalysts and processes for the use of such catalysts in isotactic polymerization of a C3+ ethylenically unsaturated monomer. The supported catalysts comprise a particulate silica support, an alkyl alumoxane component, and a metallocene catalyst component. The support has an average particle size of 10-50 microns, a surface area of 200-800 m2/g and a pore volume of 0.9-2.1 milliliters per gram (ml/g). Alumoxane is incorporated onto the support to provide a weight ratio of alumoxane to silica of at least 0.8:1.

Abstract: The present invention provides a metallocene compound which produces an olefin polymer having a high molecular weight with a high stereoregularity.

Abstract: A process for the preparation of ligands for metallocene catalysts used in the production of amorphous polymers of alpha-olefins having high molecular weight and narrow molecular weight distributions, in which the isotactic sequences are more abundant than the syndiotactic ones.

Abstract: Organometallic transition metal compounds of the formula (I) where M1 is an element of group 3, 4, 5 or 6 of the Periodic Table of the Elements or the lanthanides; X are identical or different and are each halogen, hydrogen, C1-C20-alkyl, C2-C20-alkenyl, C6-C22-aryl, alkylaryl or arylalkyl having from 1 to 10 carbon atoms in the alkyl part and from 6 to 22 carbon atoms in the aryl part, —OR5 or —NR5R6, where two radicals X may also be joined to one another or two radicals X may together form a substituted or unsubstituted diene ligand, in particular a 1,3-diene ligand; where R5 and R6 are each C1-C10-alkyl, C6-C15-aryl, alkylaryl, arylalkyl, fluoroalkyl or fluoroaryl each having from 1 to 10 carbon atoms in the alkyl radical and from 6 to 22 carbon atoms in the aryl radical; n is a natural number from 1 to 4 which is equal to the oxidation number of M1 minus 2; R1 is a C2-C40 radical which is branched in the &agr; position; R2 is hydrogen or a C1-C40 radical which may be branched or unbranched in

Abstract: A metallocene compound of a metal M of group 4 in the table of elements, comprising a cyclopentadienyl group and at least one oligomeric group R′ bonded to M, having the following formula (II): -(AxDyUz)RI  (II) wherein: A represents any monomeric unit deriving from a vinylaromatic group polymerizable by means of anionic polymerization, having from 6 to 20 carbon atoms; D represents any monomeric unit deriving from a conjugated diolefin polymerizable by means of anionic polymerization, having from 4 to 20 carbon atoms; U represents any generic optional monomeric unit deriving from an unsaturated compound copolymerizable with any of the above conjugated diolefins D or vinylaromatic compounds A; RI represents hydrogen or a hydrocarbyl group having from 1 to 20 carbon atoms, each index “x” and “y” can be independently zero or an integer, provided the sum (x+y) is equal to or higher than 2, preferably between 2 and 50, more preferably between 2 and 25; “z

Abstract: A composition of matter comprising a compound having the general formula: [CpM(ArF)Y]p wherein Cp is a substituted or unsubstituted cyclopentadienyl ligand or cyclopentadienyl-type bulky ligand characterized by one or more open, acylic or fused ring systems comprised of atoms selected from Groups 13-16 of the Periodic Table of Elements and wherein the ligands can include a heteroatom; M is a metal selected from Groups 3-9 of the Periodic Table of Elements; ArF is a fluorinated aryl group; Y is a hydrocarbyl group that can contain a heteroatom; and p is 1 or 2. The invention also contemplates a method of producing the compound and its use in the oligomerization and polymerization of alpha olefins.

Abstract: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The metallocene compositions may be represented by the formula: wherein R9 and R11 are identical or different and are a Group 14 radical having from 1 to 20 carbon atoms or are each primary, secondary or tertiary butyl groups, aryl groups, isopropyl groups, fluoroalkyl groups, trialkyl silyl groups, or other groups of similar size.

Abstract: The present invention relates to a catalyst for polymerization of &agr;-olefin, which comprises: an essential component (A) of a transition metal compound, an essential component (B) of an ion exchangeable layer compound except for silicate, or an inorganic silicate, and an optional component (C) of an organoaluminum compound, said component (A) being represented by the general formula (I):

Abstract: The present invention is a method for recycling an organometallic compound for MOCVD comprising extracting an unreacted organometallic compound from a used raw material which has undergone a thin film production process, wherein the unreacted organometallic compound is extracted after the used raw material is subjected to a reforming treatment. The method for reforming the used raw material is either a method for contacting the used raw material with a hydrogenation catalyst or a reducing agent or a method for contacting the used raw material with either a halogen, a hydrogen halide, an inorganic acid, an alkene, or a diene. In this case, an organometallic compound of higher purity can be obtained through this recycling method by contacting the used raw material with a decoloring agent comprising activated carbon, silica, or activated clay.

Abstract: Ethylene based polymers having high molecular weights can be obtained in high yields at temperatures of industrial interest, by carrying out the polymerization reaction in the presence of catalysts comprising silicon bridged metallocenes having a particular ligand system containing a heteroatom.

Abstract: A composition of matter comprising a compound having the general formula:

Abstract: The invention describes ligands of formula (I), wherein LIG represents an &eegr;5-ligand substituted by a group R1 and a group (R″)m; X represents a 1 to 3 atom bridge; Y represents a nitrogen or phosphorus atom; Z represents a carbon, nitrogen or phosphorus atom.

Abstract: Metal complexes comprising a polycyclic, fused ring ligand or inertly substituted derivative thereof comprising at least: (1) a cyclopentadienyl ring, (2) a 7 membered polyatomic ring, and (3) one or more aromatic ring systems, with the proviso that said 7 membered ring (2), is fused to both the cyclopentadienyl ring (1), and said one or more aromatic ring systems (3), and substituted in at least one ring position with a substituent group resulting in sp2 hybridization on the ring atom bonded thereto; polymerization catalysts; and olefin polymerization processes using the same are disclosed.

Abstract: The invention provides a method for the preparation of a metallocene halide salt having at least one cyclopentadiene group substituted by a basic group, the method comprising reacting together a metal halide with a cyclopentadiene substituted by a basic group. In a preferred embodiment, the substituted cyclopentadiene is substituted with an amino group and the metal halide titanium tetrachloride. The invention provides a single step process for the preparation of metallocene derivatives which are useful in the formulation of medicaments and as polymerisation catalyst precursors.

Abstract: Supported metallocene catalysts and processes for the use of such catalysts in isotactic polymerization of a C3+ethylenically unsaturated monomer. The supported catalysts comprise a particulate silica support, an alkyl alumoxane component, and a metallocene catalyst component. The support has an average particle size of 10-50 microns, a surface area of 200-800 m2/g and a pore volume of 0.9-2.1 milliliters per gram (ml/g). Alumoxane is incorporated onto the support to provide a weight ratio of alumoxane to silica of at least 0.8:1.

Abstract: Use of metallocene catalyst component for the preparation of a syndiotactic polyolefin having a monomer length of up to C10, which component has the general formula: R″(CpR1R2)(Cp′R1′R2′)MQ2 wherein Cp is a cyclopentadienyl ring; Cp′ is a 3,6 disubstituted fluorenyl ring; R1 and R2 are each independently H or a substituent on the cyclopentadienyl ring which is proximal to the bridge, which proximal substituent is linear hydrocarbyl of from 1 to 20 carbon atoms or a group of the formula XR*3 containing up to 7 carbon atoms in which X is chosen from Group IVA, and R* is the same or different and chosen from hydrogen or alkyl; R1′ and R2′ are each independently substituent groups on the fluorenyl ring, each of which is a group of the formula AR′″3, in which A is chosen from Group IVA, and each R′″ is independently hydrogen or a hydrocarbyl having 1 to 20 carbon atoms; M is a Group IVB transition metal or vanadium; each Q is hydrocarbyl having 1 to

Abstract: Compounds and metal complexes comprising a polycyclic, fused ring ligand or inertly substituted derivative thereof having up to 60 atoms other than hydrogen, said ligand comprising at least: (1) a cyclopentadienyl ring, (2) a 6, 7, or 8 membered ring other than a 6-carbon aromatic ring, and (3) an aromatic ring, with the proviso that said 6, 7, or 8 membered ring (2), is fused to both the cyclopentadienyl ring (1), and the aromatic ring (3), polymerization catalysts, a process to prepare the novel compounds and complexes, and olefin polymerization processes using the same are disclosed.

Abstract: The present invention provides to a catalytic system, its method for preparation, and a method for preparation of a copolymer of ethylene and a conjugated diene, which uses this catalytic system. A catalytic system according to the invention comprises: an organometallic complex compound, which is represented by one formula A or B: in which Ln represents a metal of a lanthanide, the atomic number of which is between 57 and 71; X represents a halogen, which can be chlorine, fluorine, bromine or iodine; and Cp1 and Cp2 each comprise a cyclopentadienyl or fluorenyl group, which is or is not substituted, and P is a bridge corresponding to the formula MR2, in which M is an element of column IVA of Mendeleev's periodic classification, and R is an alkyl group comprising from 1 to 20 atoms of carbon; and a co-catalyst selected from among a magnesium alkyl, a lithium alkyl, an aluminium alkyl, or a Grignard's reagent, and mixtures thereof.

Abstract: A process for separating inorganic and organometallic by-products from a mixture comprising at least one organometallic transition metal compound as product and at least one organometallic by-product and at least one inorganic by-product as by-products comprises the steps

Abstract: Highly substituted alkyl-bridged ligand systems based of indene derivatives and transition metal compounds can be obtained in high yields by a novel process.

Abstract: A process is described for the preparation of elastomeric EP(D)M copolymers and terpolymers, characterized in that it is carried out in the presence of metallocene compounds of general formula (I) having a racemic stereoisomerism.

Abstract: A new process is disclosed, particularly simple, convenient and practical, for the direct synthesis of titanium complexes of the formula (I): (D)(ZR1m)n(A)TiLpXq, wherein (ZR1m)n is a divalent group bridging D and A; D is a delocalized &pgr;-bonded moiety, which is bound in an &eegr;5 bonding mode to Ti, and is preferably a Cp moiety; A is —O—, —S—, —N(R2)— or —P(R2)—, wherein R2 is hydrogen, alkyl, cycloalayl, aryl, alkylaryl or arylalkl; L are monoanionic sigma ligands selected from alkyl, cycloalkyl, aryl, alkylaryl and arylalkyl groups; m is 1 or 2; n is 1-3; p is 1 or 2, q is 0 or 1 and p+q=2; said process comprises reacting a ligand of formula (H—D)(ZR1m)n(A—H) with about 1 molar equivalent of TiX4 in the presence of about (2+p) molar equivalent of LjB or LMgX wherein X is halogen or —OR′, B is an alkaline or alkaline-earth metal, and j is 1 or 2.

Abstract: A metallocene catalyst in which the metal is coordinated by a &eegr;5 cyclopentadienyl ligand which forms part of an indenyl or indenyloid moiety, characterised in that said moiety is directly or indirectly substituted at the 4-, 5-, 6- or 7-position by a pendant siloxy or germyloxy group.

Abstract: The present invention relates to a transition metal compound represented by the general formula (I), and a olefin polymerization catalyst comprising above transition metal compound and activating co-catalyst as the main components. (wherein, M represents a metal element in the groups 3 to 10 of the periodic table or in the lanthanoide series, X represents a &sgr; bonding ligand bonded to M, Y represents a Lewis base, A represents a cross-linking group, p is an integer of 1 to 20, q is an integer of 1 to 5 and represents [(valence of M)−2], r is an integer of 0 to 3. R1 represents a group in above R2 to R9 except hydrogen atom). The present invention provides a transition metal compound useful for olefin polymerization catalyst, and olefin polymerization catalyst using above compound.

Abstract: A new class of methylene-bridged metallocenes of formula (I), wherein M is a transition metal of group 3, 4, 5, 6, lanthanide or actinide; X is a monoanionic sigma ligand; R1 can be alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl radicals; R2 can be halogen, alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl radical; p is 0-3; m is 0-2; and n is 0-4. Furthermore, the corresponding ligands, a new process for their preparation and catalysts systems containing said methylene-bridged metallocenes are described.

Abstract: A process for preparing dihalide or monohalide metallocene compounds comprising contacting a compound of formula (II) (Cp)(ZR1m)n(A)rML′y(II) wherein Cp is a cyclopentadienyl radical; (ZR1m)n is a divalent bridging group between Cp and A; A is a cyclopentadienyl radical or 0, S, NR2, PR2 wherein R2 is an hydrocarbon radical, M is zirconium, titanium or hafnium, L′ is an hydrocarbon radical, r ranges from 0 to 2 and y is equal to 4; with an halogenating agent selected from the group consisting of: T1Lw1 wherein T1 is a metal of groups 3-13 of the periodic table; L is halogen and w1 is equal to the oxidation state of the metal T1; T2Lw2 wherein T2 is a nonmetal element of groups 13-16 of the periodic table (new IUPAC version); and w2 is equal to the oxidation state of the element T2; O=T3Lw3 where T3 is a selected from the group consisting of C, P and S; O is an oxygen atom bonded to T3 trough a double bond; and w3 is equal to the oxidation state of the element T3 minus 2; R6C(O)L, wherein R6

Abstract: The invention relates to a process for preparing transition metal compounds having hydrogenated or partially hydrogenated monocyclic, bicyclic or polycyclic ligands, which is characterized in that the unsaturated monocyclic, bicyclic or polycyclic transition metal compound together with hydrogen is introduced continuously or all at once under pressure into a static mixer in the presence of a suitable solubilizer and a catalyst.

Abstract: A method is provided for the polymerization of olefins substituted with a functional group using a transition metal catalyst that, by virtue of one or more stabilizing groups incorporated within the catalyst structure, “fixes” the stereoconfiguration of each olefinic monomer relative to the transition metal complex during each successive reaction in the polymerization process. The invention substantially reduces the likelihood of olefin rearrangement at the active site of the catalyst during polymerization. In one particular embodiment, the functional group is a polar, electron-donating group and the stabilizing group is a Lewis acid substituent; examples of polymers that can be prepared with such a system include poly(vinyl acetate), poly(vinyl alcohol), and poly(vinyl ethers). Novel complexes and catalyst systems useful in the polymerization method are also provided.

Abstract: Metallocene compounds represented by the following general formula (1):

Abstract: In metallocene complexes of a metal of transition group IV, V or VI of the Periodic Table, at least one substituted or unsubstituted cyclopentadienyl radical is bound to an element of group III of the Periodic Table which is in turn a constituent of a bridge between this cyclopentadienyl radical and the metal atom and bears an organonitrogen, organophosphorus or organosulfur group as sole further substituent.

Abstract: A process for producing substantially amorphous propylene (co)polymers, comprising contacting propylene optionally in the presence of one or more olefins under polymerization conditions with a catalyst system comprising: A) a half sandwich titanium complex wherein the cyclopentadienyl is substituted with one or two heterocyclic rings, according to formula (I): cf formula (I) in claim 1: wherein X is N or P; Z is C, Si or Ge; Y1 is an atom selected from the group consisting of NR7, O, PR7 or S; Y2 is selected from the group consisting of CR8 or Y1 and m is 0 or 1 and B) an activating cocatalyst. The above titanium complex and the ligand useful as intermediates in their synthesis are also described.

Abstract: The object of the present invention is to provide a method for producing a dinuclear transition metal complex of formula (1) by reacting cyclopentadienyl ligand compound of formula (2) and substituted transition metal of formula (3). Cp-Si(R)2HNANHSi(R)2-Cp  (Formula 2) wherein, A represents C2-30 alkylene, substituted alkylene, arylene, substituted arylene, cycloalkylene, substituted cycloalkylene, biarylene or substituted biarylene; Cp represents a ligand compound having cyclopentadienyl skeleton selected from the group consisting of cyclopentadienyl, substituted cyclopentadienyl, indenyl, substituted indenyl, fluorenyl and substituted fluorenyl; R represents C1-20 alkyl or substituted alkyl; H represents hydrogen atom; Si represents silicon atom; and N represents nitrogen atom. M(NR2′)4  (Formula 3) M represents transition metal of Periodic Table IV selected from titanium, zirconium and hafnium; R′ represents C1-6 alkyl.

Abstract: The present invention relates to organometallic compounds of transition metals with an indenyl ligand bonded in the 2-position and substituted in the 1,3-position, a process for their production, and their use as catalysts for the (co)polymerization of olefinic and/or diolefinic monomers.

Abstract: A syndiotactic polyolefin is obtained in a high yield by polymerization or copolymerization of an olefin of the formula Ra—CH═CH—Rb in the presence of a catalyst consisting of a metallocene of the formula I in which M1 is titanium, zirconium, vanadium, niobium or tantalum, and an aluminoxane. This polyolefin has a very high molecular weight, a very narrow molecular weight distribution and a very high syndiotactic index. Shaped articles produced from the polymer are distinguished by a high transparency, flexibility, tear resistance and an excellent surface gloss.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system includes an organometallic complex that incorporates a Group 3 to 10 transition metal and an anionic, polycyclic, convex ligand. Molecular modeling results indicate that the complexes, when combined with an activator, should actively polymerize olefins. The convex ligand uniquely stabilizes the active site while simultaneously minimizing steric interference. Calculations predict that complexes based on ligands with a high curvature index will have favorable reactivities with olefin monomers compared with similar complexes that incorporate Cp-like ligands.

Abstract: The present invention relates to a metallocene compound having a functional group that facilitates the preparation of the supported metallocene catalyst for olefin polymerization and the olefin polymerization process using the same. The metallocene compounds in this invention are strongly supported on the inorganic support due to the strong chemical bond of the ligand of the metallocene compound with the silica surface, which leads to minimize leaching of the catalyst during the activation process. Therefore, the supported catalyst of this invention allows the olefin polymerization process to proceed without any fouling in the reactor with a slurry or a gas phase process, and the morphology and bulk density of the polymer produced are much better defined than those produced by conventional methods.

Abstract: A new class of methylene-bridged metallocenes of formula (I), wherein M is a transition metal of group 3, 4, 5, 6, lanthanide or actinide; X is a monoanionic sigma ligand; R1 can be alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl radicals; R2 can be halogen, alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl radical; p is 0-3; m is 0-2; and n is 0-4. Furthermore, the corresponding ligands, a new process for their preparation and catalysts systems containing said methylene-bridged metallocenes are described.

Abstract: A method for producing dialkylsilylbis(2-alkyl-4-aryl indenyl) titanocenes including rac-Me2Sibis(2-methyl-4-phenylindenyl)-titanium dichloride is described.