Abstract: A liquid cyclopentene ring-opened copolymer includes a monomer unit derived from cyclopentene and a monomer unit derived from a norbornene compound, the monomer unit derived from cyclopentene being present in an amount of 60 to 95 wt %, the liquid cyclopentene ring-opened copolymer having a hydroxyl group-terminated copolymer chain and having a melt viscosity at 25° C. of less than 500 Pa·s, which is measured using a B-type viscometer.

Abstract: A method comprising introducing a polymerization feed comprising an ?-olefin, a diluent, and a diene to a polymerization system, under polymerization conditions, whereby a polymer product is produced, wherein the diene is present at a level in the range of from about 1 ppm to about 1000 ppm based on the diluent.

Abstract: The present disclosure is directed towards a solution or bulk polymerization process for preparing high-cis polydienes that utilizes at least one vinyl aromatic compound as a molecular weight regulator. The disclosed solution or bulk polymerization processes are useful for preparing high-cis polydienes with a Mooney viscosity between 30 and 55 while allowing the use of lower amounts of catalyst.

Abstract: Catalyst component for the polymerization of olefins comprising Mg, Ti and an electron donor compound of the following formula (I) In which R1 to R4 groups, equal to or different from each other, are hydrogen, C1-C15 hydrocarbon groups, optionally containing an heteroatom selected from halogen, P, S, N and Si, R6 group is selected from C1-C15 hydrocarbon groups optionally containing an heteroatom selected from halogen, P, S, N and Si, and R5 is selected from phenyl groups mono or poly substituted with halogens, said groups R1-R4 being also optionally linked to form a saturated or unsaturated mono or poly cycle.

Abstract: A process for the preparation of branched polybutadiene having a high content of 1,4-cis units which comprises polymerizing butadiene in the presence of at least one organic solvent, and in the presence of: a) a catalytic system prepared in situ including: (a1) at least one neodymium carboxylate, (a2) at least one alkyl compound of aluminum, (A3) at least one alkyl compound of aluminum containing at least one halogen atom, and b) at least one organic ester containing at least one halogen atom. Said branched polybutadiene having a high content of 1,4-cis units, depending on the branching degree and molecular weight distribution, can be advantageously used in various applications ranging from the modification of plastic materials [production, for example, of high impact polystyrene (HIPS)] to the production of tyres, in particular the production of treads and/or of sidewalls of tyres.

Abstract: A polymerization process includes contacting the following in a gas-phase reactor system under polymerization conditions for making a polymer product: a metallocene-based catalyst system including a supported constrained geometry catalyst, at least one monomer, and an additive selected from a group consisting of an aluminum distearate, an ethoxylated amine, and a mixture thereof. The additive may be selected from a group consisting of an aluminum distearate, an ethoxylated amine, polyethylenimines, and other additives suitable for use in the production of polymers for food contact applications and end products, including a mixture of a polysulfone copolymer, a polymeric polyamine, and oil-soluble sulfonic acid, in a carrier fluid, and mixtures thereof.

Abstract: The present disclosure provides compositions for alkyne metathesis catalysts and methods for preparing enediynes and alkyne metathesis catalysts. The disclosure also provides methods for catalyzing alkyne metathesis reactions and polymerization of enediyne substrates to polydiacetylenes in solution-phase.

Abstract: A process and the resultant product from the process for continuously making an EPDM utilizing ethylene, propylene, and dienes. This process allows for the creation of products with high diene contents and broad molecular weight distributions while utilizing a continuous flow reactor and a known catalyst. The process allows for these products to be made without gelling, or fouling of the reactor, which are problems known in the art.

Abstract: A process for continuously making a terpolymer or a tetrapolymer utilizing ethylene, an alpha olefin, and at least one polyene. This process allows for the creation of products with high polyene contents and broad molecular weight distributions while utilizing a continuous flow reactor and a known catalyst. The process allows for these products to be made without gelling, or fouling of the reactor.

Abstract: Process for the preparation of a polypropylene, wherein propylene is polymerized optionally with a comonomer selected from the group consisting of ethylene, a C4-C20 ?-olefin and mixtures thereof, in the presence of a catalyst system comprising solid catalyst particles, wherein the solid catalyst particles (a) comprise a transition metal compound of formula (I) LmRnMXq (I) wherein “M” is a transition metal of anyone of the groups 3 to 10 of the periodic table (IUPAC), each “X” is independently a monovalent anionic ?-ligand, each “L” is independently an organic ligand which coordinates to the transition metal (M), each “R” is a bridging group linking two organic ligands (L), “m” is 2 or 3, preferably 2, “n” is 0, 1 or 2, preferably 1, “q” is 1, 2 or 3, preferably 2, m+q is equal to the valency of the transition metal (M), (c) comprise a cocatalyst (Co) comprising an element (E) of group 13 of the periodic table (IUPAC), preferably a cocatalyst (Co) comprising a compound of A1, wherein further the loss of activ

Abstract: Disclosed is a method for preparing a solid catalyst for polymerization of polypropylene. The method includes: a) reacting a magnesium halide compound with alcohol and then adding a phthalic acid compound thereto to prepare a magnesium compound solution; b) mixing an aliphatic or alicyclic hydrocarbon solvent with an aromatic hydrocarbon solvent to prepare a mixed solvent, dispersing a titanium compound in the mixed solvent, and then reacting the titanium compound dispersed with the magnesium compound solution prepared in step a), and heating to produce a support; and c) reacting the support with the titanium used before disperse in step b) compound and an electron donor to obtain a solid product. When a catalyst prepared by the present disclosure is used, polypropylene with high activity and high bulk density characteristics may be prepared.

Abstract: There are provided (I) a process for producing a copolymer of ethylene, an ?-olefin having from 3 to 20 carbon atoms and optionally a polyene, which comprises the step of copolymerizing those monomers in a polymerization reactor by feeding the following components (A), (B), (C1) and (D) to the polymerization reactor: (A) a transition metal complex, (B) an organic aluminum compound, (C1) a halogen-containing compound, and (D) a Lewis base, wherein those components are fed to the polymerization reactor without a preliminary contact of (1) the component (A) with the component (B), (2) the component (A) with the component (C1), (3) the component (B) with the component (C1), and (4) the component (B) with the component (D); and (II) a process for producing said copolymer, which comprises the step of copolymerizing those monomers in a polymerization reactor (i) by feeding to the polymerization reactor the components (A), (B), (D), (C2) a halogen-containing compound, which is a derivative of an aryl group-contai

Abstract: Compositions useful for activating catalysts for olefin polymerization are-provided. The compositions are derived from at least: a) compound derived from at least (i) carrier having at least one pair of hydrogen bonded hydroxyl groups, (ii) organoaluminum compound, and (iii) Lewis base, such that each of a majority of aluminum atoms in the organoaluminum compound forms chemical bonds with at least two oxygen atoms from the at least one pair of hydrogen bonded hydroxyl groups; and b) Bronsted acid, wherein the molar ratio of the Bronsted acid to the organoaluminum compound is less than or equal to about 2:1.

Abstract: Disclosed herein is a multimodal polymer composition comprising 45 to 75 wt % of a first polymer fraction, 25 to 55 wt % of a second polymer fraction, and from 10-50 phr of an extender oil. The multimodal polymer composition has an overall Mooney viscosity of less than 90 ML(1+4@125° C.), and each polymer fraction comprises an ethylene, C3-C10 alpha-olefin, non-conjugated diene polymer, wherein the first polymer fraction has a Mooney viscosity of greater than or equal to about 150 ML(1+4@125° C.), the second polymer fraction has a Mooney viscosity from about 20 to about 120 ML(1+4@125° C.). A process for making the multimodal polymer composition comprising a process utilizing two or more reactors in series is also disclosed.

Abstract: A composition useful for activating catalysts for olefin polymerization Is provided. The composition is derived from at least: carrier; treated organoaluminoxy compound: and ionic compound having at feast one active proton.

Abstract: A nickel-carbene polymerization catalyst system for preparing high cis polydienes is provided. The catalyst system comprises (a) a nickel N-heterocyclic carbene complex, (b) an organoaluminum compound, (c) a fluorine-containing compound, and (d) optionally, an alcohol. Also provided is a process for producing a polydiene comprising reacting a conjugated diene in the presence of a polymerization catalyst comprising (a) a nickel N-heterocyclic carbene complex, (b) an organoaluminum compound, (c) a fluorine-containing compound, and (d) optionally, an alcohol.

Abstract: A process for producing a modified particle, which comprises the step of contacting a compound (a) defined by the formula, M1L13, a compound (b) defined by the formula, R1t-1TH, a compound (c) or (e) defined by the formula, R2m-uM2(OH)u or R24-nJ(OH)n, respectively, and a particle (d) with one another; a carrier comprising a modified particle produced by said process; a catalyst component (A) comprising a modified particle produced by said process; a process for producing a catalyst for addition polymerization, which comprises the step of contacting said catalyst component (A), a transition metal compound (B) and an optional organoaluminum compound (C) with one another; and a process for producing an addition polymer, which comprises the step of addition polymerizing an addition-polymerizable monomer in the presence of a catalyst for addition polymerization produced by said process.

Abstract: An ethylene-based polymer which is an ethylene/C4 to C10 ?-olefin copolymer and satisfies the following requirements [k1] to [k3]: [k1] melt flow rate (MFR) under a loading of 2.16 kg at 190° C. is in the range of 1.0 to 50 g/10 minutes; [k2] LNR defined as a scale of neck-in upon film molding is in the range of 0.6 to 1.4; and [k3] take-up speed at break [DS (m/min)] at 160° C. and melt flow rate (MFR) satisfy the following relationship (Eq-1): 12×MFR0.577?DS?165×MFR0.577 (Eq-1), and a thermoplastic resin composition containing the ethylene-based polymer, provide a molded product, preferably a film, excellent in moldability and mechanical strength.

Abstract: A catalyst component for ethylene polymerization, including an inorganic oxide support, and at least one alkyl metal compound, at least one halide, at least one dihydrocarbyl magnesium compound, at least one difunctional compound that reacts with the dihydrocarbyl magnesium compound and at least one titanium compound, wherein the difunctional compound is a mono-, di- or multi-halogenated alcohol or phenol having from 2 to 20 carbon atoms; or a mono-, di- or multi-halogenated acyl halide having from 2 to 20 carbon atoms. Also, a process for preparing the catalyst component and use thereof.

Abstract: This invention is based upon the discovery that a catalyst system which is comprised of (a) palladium or a palladium compound and (b) a fluorinated alcohol is effective for polymerizing norbornene-functional monomers into polynorbornene-functional polymers. It has been further discovered that this catalyst system is more effective in polymerizing certain norbornene-functional monomers that are difficult to polymerize, such as norbornene ester monomers, than prior art catalyst systems. The activity of the catalyst systems of this invention can be further improved with respect to polymerizing some monomers by including a Lewis acid and/or a ligand, such as a phosphine or a carbene, in the system. In any case, the catalyst systems of this invention offer the advantage of being soluble in a wide variety of solvents, relatively inexpensive, and capable of polymerizing many norbornene-functional monomers that are difficult to polymerize with conventional catalyst systems.

Abstract: This invention is based upon the discovery that a catalyst system which is comprised of (a) palladium or a palladium compound and (b) a fluorinated alcohol is effective for polymerizing norbornene-functional monomers into polynorbornene-functional polymers. It has been further discovered that this catalyst system is more effective in polymerizing certain norbornene-functional monomers that are difficult to polymerize, such as norbornene ester monomers, than prior art catalyst systems. The activity of the catalyst systems of this invention can be further improved with respect to polymerizing some monomers by including a Lewis acid and/or a ligand, such as a phosphine or a carbene, in the system. In any case, the catalyst systems of this invention offer the advantage of being soluble in a wide variety of solvents, relatively inexpensive, and capable of polymerizing many norbornene-functional monomers that are difficult to polymerize with conventional catalyst systems.

Abstract: An organometallic composition which can be used as activating component in a metallocene catalyst for the (co)polymerization of ?-olefins, comprises: (A) a fluorinated di-unsaturated cyclic compound, having a relatively acid hydrogen atom, (B) an organometallic compound sufficiently basic to react with the acid hydrogen of the above compound (A), and (C) a polar aprotic organic compound, not containing metallic atoms, having a dielectric constant, in the pure state, equal to or greater than 2, and a weak coordinating capacity. Said composition allows a metallocene catalytic system of the ionic type to be obtained, with a high activity in the (co)polymerization of olefins and a reduced content of metallic residue in the polymeric product thus obtained.

Abstract: A cyclic olefin having a specific polar group is polymerized by addition polymerization in a hydrocarbon solvent, using a polymerization catalyst component containing (i) a specific transition metal compound, (ii) a Lewis acid compound and (iii) an alkyl aluminoxane, or the cyclic olefin is polymerized by addition polymerization in the hydrocarbon solvent, using the polymerization catalyst component, by further adding at least one aromatic vinyl compound and at least one cyclic nonconjugated polyene compound, or either one of them as a molecular weight modifier, thereby obtaining a cyclic olefinic addition polymer.

Abstract: The present invention provides an ethylene copolymer resin that has unique melt elastic properties not observed in ethylene copolymers heretofore known. Specifically, the ethylene copolymer resin of the present invention when in pelletized form has a reduction in melt elasticity (ER) of 10% or more to a final value of 1.0 or less upon rheometric low shear modification or solution dissolution. Moreover, the resin of the present invention when in reactor-made form exhibits at least a partially reversible increase of 10% or more in ER when pelletizing the same. An ethylene polymerization catalyst, a process of preparing the ethylene copolymer resin and a high-impact film are also provided herein.

Abstract: The present invention relates to a silica gel-supported catalyst component suitable for ethylene (co)polymerization, a catalyst therefrom and use of the same. The catalyst component according to the present invention is obtained by supporting the reaction product of a titanium compound, a halide promoter, a magnesium compound and an electron donor on silica gel having a larger specific surface area. When the resultant catalyst is used for ethylene polymerization, especially gas phase fluidized bed polymerization, not only the activity is substantially enhanced, but also the hydrogen response and the copolymerizability of ethylene with other alpha-olefins are improved. The catalyst is especially suitable for the fluidized bed polymerization operated in a condensed state, with high quality LLDPE resins being obtained.

Abstract: A novel process for the polymerization of olefins is provided. The process involves contacting at least one olefin with a Ziegler-Natta type catalyst in the presence of a specified compound that results in the production of polymeric products having a narrower molecular weight distribution. Also provide is a process for narrowing the molecular weight distribution of a polyolefin comprising contacting an olefin, a Ziegler-Natta catalyst and a compound specified herein. Further provided are novel polyethylenes, and films and articles produced therefrom.

Abstract: A process to produce a propylene polymer is provided. The process comprising contacting at least one organometal compound, at least one organoaluminum compound, at least one treated solid oxide compound, propylene, and ethylene in a polymerization zone under polymerization conditions to produce the propylene polymer.

Abstract: There are disclosed a process for producing a solid catalyst component and a catalyst for &agr;-olefin polymerization, and a process for producing an &agr;-olefin polymer, wherein the process for producing a solid catalyst component comprises the steps of: (1) reducing a specific titanium compound with an organomagnesium compound in the presence of an organosilicon compound having an Si—O bond (and an ester compound), thereby obtaining a solid product, and (2) contacting the solid product with at least one member selected from the group consisting of an electron donor compound (E1) and an organic acid halide, and a compound having a Ti-halogen bond, thereby obtaining the solid catalyst component.

Abstract: A catalyst composition that is the combination of or the reaction product of ingredients comprising (a) (i) a halogen-containing iron compound or (ii) an iron-containing compound and a halogen-containing compound, (b) a silyl phosphonate, and (c) an organoaluminum compound.

Abstract: A conjugated diene polymer is produced by continuously polymerizing a conjugated diene monomer with a catalyst consisting essentially of components (1): a lanthanoid compound, (2): an aluminoxane and (3): a halogenated organometal compound, a halogenated metal compound or a halogenated organic compound in a hydrocarbon solvent containing 5-50% by weight of an aromatic hydrocarbon to obtain a conjugated diene polymer having a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) of not more than 4.

Abstract: A process for production of an ethylene-propylene-diene-methylene (EPDM) tetrapolymer having long chain branching is described. The process comprises the step of polymerizing a monomer mixture comprising ethylene, propylene, a first diolefin monomer containing one polymerizable double bond (preferably ENB) and a second diolefin containing two polymerizable double bonds (preferably VNB) in the presence of a catalyst system. The catalyst system comprises: a catalyst comprising a compound containing vanadium +3 with the proviso that the compound does not comprise a halogen directly bound to the vanadium; a halogenated organoaluminum cocatalyst having a halogen to aluminum molar ratio in the range of from about 1 to about 2; and an activator. The branched polymer product of the present process exhibits a molecular weight distribution of less than about 3.5 and improved rheological properties and enhanced processability characteristics.

Abstract: This invention relates to a process for polymerizing isobutene using a catalytic system comprising a transition metal compound, a benzene derivative compound, and methylaluminoxane, and the catalytic system applied to the polymerization of isobutene, (1) the added benzene derivative compound and methyl aluminoxane to the transition metal species provides higher stability of cation active site so that polyisobutene with a high molecular weight can be produced even at a higher reaction temperature than the conventional cationic polymerization temperature; (2) nonhalogen solvent such as toluene can be employed as a polymerization solvent instead of halogenated solvents such as methyl chloride; and (3) under the stable catalytic system, a final product with a high yield can be ensured for its long-term use.

Abstract: A catalyst for the polymerization of vinylaromatic monomers, and particularly styrene, with a high yield and a high syndiotacticity index, comprises the product consisting of the following two components in contact with each other: A) an &eegr;5-cyclopentadienyl complex of titanium; B) an organo-oxygenated compound of aluminum; and contains a sufficient amount of at least one carboxylated product having the following general formula: R—COO—G  (I) wherein R—COO is a carboxylic group comprising the organic radical R having from 1 to 30 carbon atoms, and G represents a hydrogen atom, an aliphatic or aromatic hydrocarbon group having from 1 to 20 carbon atoms or a metal atom, possibly substituted, linked to said carboxylic group.

Abstract: The present invention relates to a catalyst system comprising: a) an organoaluminum compound, b) a metal compound selected from subgroups IV to VI of the periodic system, c) a reactivator in a molar ratio of 0.5 to 100 relative to compound b), wherein said reactivator comprises a characterized in that a mono- or dihalocarboxylic acid alkyl ester of the following formula: wherein X is a C1-6 alkyl or C1-6 alkoxy group, Y is Cl, Br or H, Z is Cl or Br and R is a C1-6 alkyl group.

Abstract: This invention relates to an initiator system for the polymerization of isoolefins having 4 to 16 carbon atoms, optionally with monomers polymerizable with isoolefins, the system consisting of or one or more aromatic or heteroaromatic, polycyclic hydrocarbons and an aged, organic solution of vanadium tetrachloride, wherein the concentration of the vanadium tetrachloride is 0.01 mmol to 500 mmol per liter of solvent and the molar ratio of aged vanadium tetrachloride to polycyclic hydrocarbons is in the range from 100:1 to 1:100.It is possible by means of the initiator system according to the invention to produce polyisoolefins, in particular butyl rubbers, at relatively high temperatures with only a low gel content and of a sufficiently high molecular weight.

Abstract: This invention relates to a process for controlling the molecular weight distribution of high 1,4-cis polybutadiene and more particularly, to a process of easily controlling the molecular weight distribution of polybutadiene which is concerned directly with the physical properties such as processability, in such a manner that preparation of high 1,4-cis polybutadiene is made available via polymerization of 1,3-butadiene in the presence of Ziegler-Natta catalyst, adding carboxylic acid represented by following formula I for the controlling of the molecular weight distribution of polybutadiene based on the contents of carboxylic acid, may be easily controlled, without any alternation in the 1,4-cis contents. ##STR1## Wherein R is selected from the group consisting of alkyl, cycloalkyl and arylalkyl groups substituted or unsubstituted with at least one or more halogen atoms, or alkyl, cycloalkyl and arylalkyl groups with at least one or more double bonds containing from 5 to 20 carbon atoms.

Abstract: There is provided process for producing an ethylene-alpha-olefin polymer at a polymerization reaction temperature in excess of the softening temperature of the polymer in a gas-phase fluidized-bed reactor in the presence of a polymerization catalyst and wherein the polymerization reaction is conducted in the presence of an inert particulate material, the improvement comprising: commencing polymerization by polymerizing an ethylene propylene rubber having a crystallinity ranging from about 4 to 18 percent as measured by differential scanning calorimetry.

Abstract: Catalysts component of the (co)polymerization of alpha-olefins CH.sub.2 .dbd.CHR, wherein R is hydrogen or an alkyl radical having from 1 to 8 carbon atoms, comprising a product of the composition:VCL.sub.y.z(b)wherein (b) represents an organic compound selected from alkyl, aryl and acyl halides, y is a number higher than 2 and lower than 4, and preferably comprised between 2.5 and 3.5 and z is a number higher than zero and lower than or equal to 2, and preferably between 0.002 and 1. Components can be obtained as products of the reaction, carried out at temperatures higher than 10.degree. C., between VCl.sub.4 and the compound (b). Particularly preferred among compounds (b) are benzoyl chloride, p-methoxybenzoyl chloride and p-chloro benzoyl chloride. From the components of the invention, either supported or not, catalysts having high activity particularly useful for the production of ethylene polymers showing broad molecular weight distribution can be prepared.

Abstract: It has been determined that 1,3-butadiene monomer can be polymerized into cis-l,4-polybutadiene rubber utilizing a cobalt-based catalyst system which is comprised of (a) an organocobalt compound, (b) a trialkylaluminum compound and (c) hexafluoro-2-propanol. The use of this catalyst system results in extremely fast rates of polymerization. The molecular weight of the cis-1,4- polybutadiene rubber made utilizing this cobalt-based catalyst system can be regulated by conducting the polymerization in the presence of 1,5-cyclooctadiene. This present invention more specifically discloses a catalyst system which is particularly useful for polymerizing 1,3-butadiene monomer into cis-1,4-polybutadiene, said catalyst system being comprised of (a) an organocobalt compound, (b) a trialkylaluminum compound and (c) hexafluoro-2-propanol.

Abstract: A colorable resin particle having an outer shell of a non-sticky polymer and an inner core of a sticky polymer produced in a gas phase fluidized bed reactor at or above the sticking temperature of the sticky polymer using a non-sticky prepolymerized catalyst and processes for producing the colorable resin and the non-sticky prepolymerized catalyst.

Abstract: Process with two or more steps for the preparation in suspension of mixtures of ethylene-propylene (EPM) elastomer homopolymers or ethylene-propylene-diene (EPDM) elastomer terpolymers in the presence of a catalytic system essentially consisting of a compound of Vanadium and a cocatalyst essentially consisting of an Aluminum alkyl and in the presence of an activator, the above process being characterized in that:a) in the first step a first polymerization of the monomers is carried out in the presence of the Vanadium based catalyst;b) in the second or subsequent steps further polymerizable monomers and activator are added to the suspension of the polymer obtained in step (a).

Abstract: According to the present invention there are provided a catalyst component, a catalyst using the catalyst component and a process using the catalyst, for the preparation of olefin polymers high in molecular weight and relatively wide in molecular weight distribution, using an extremely small amount of a modified organoaluminum compound such as methylaluminoxane and in high yield. The catalyst component is prepared by contacting at least the following constituents (1), (2), (3) and (4) with one another:(1) a compound represented by the general formula Me.sup.1 R.sup.1.sub.p (OR.sup.2).sub.q X.sub.4-p-q where R.sup.1 and R.sup.2 are each independently a hydrocarbon group having 1 to 24 carbon atoms, X is a halogen atom, Me is Zr, Ti or Hf, p and q are each an integer in the ranges of 0.ltoreq.p.ltoreq.4 and 0.ltoreq.q.ltoreq.4, provided 0.ltoreq.p+q.ltoreq.4;(2) at least one compound selected from the group consisting of compounds represented by the following general formulas 1 to 4:General formula 1: Me.sup.

Abstract: Disclosed are a catalyst for olefin polymerization comprising (A) a compound of a transition metal in Group IVB of the periodic table which contains a ligand having a cyclopentadienyl skeleton, (B) an organoaluminum compound and any one of (C1) a Br.o slashed.nsted acid; (C2) a material obtained by contacting (c-1) a magnesium compound with (c-2) an electron donor; and (C3) a material obtained by contacting (c-1) a magnesium compound, (c-2) an electron donor and (c-3) an organometallic compound with each other. Also disclosed are processes for polymerizing an olefin in the presence of the above-mentioned catalysts for olefin polymerization. Such catalysts and processes for olefin polymerization as described above are excellent in olefin polymerization activity and economical efficiency.

Abstract: A process for producing a polybutadiene rubber having a cis-1,4 content of 94% or more, a ratio of weight average molecular weight to number average molecular weight of 2.5 to 3.5 as measured by a gel permeation chromatography and a Mooney viscosity (ML.sub.1+4, 100.degree. C.) of 20 to 100, which process comprises polymerizing 1,3-butadiene in an inert organic solvent with a catalyst comprising as the main components (a) a nickel compound; (b) a specific fluorine compound; (c) a trialkylaluminum; and (d) a halogenated aldehyde and/or a quinone compound. The use of the specific catalyst enables the production in a high yield of a polybutadiene rubber which maintains the abrasion resistance, high impact resilience and low heat buildup which are the characteristics of polybutadiene rubber and has a small die swell when extruded in the form of a blend with a natural rubber and is excellent in physical properties of vulcanizate.

Abstract: Diene polymers having a high content of trans-1,4 addition and two distinct melting points in the ranges of 30.degree. C. to 50.degree. C. and 70.degree. C. to 130.degree. C. are prepared by polymerizing a 1,3-diene monomer in a hydrocarbon solvent in the presence of a catalyst composition comprising (a) a carboxylated nickel oxy borate compound; (b) an orKanoaluminum compound; (c) a triaryloxy phosphorus compound and (d) a carboxylic acid preferably a fluorinated carboxylic acid. The resultant polymers are useful as additives to tire rubbers to improve processability by reducing compound Mooney viscosity and reducing the shrinkage of various compound stocks.

Abstract: A process for producing ethylene-.alpha.-olefin copolymer rubbers which comprises mixing a vanadium compound-containing solution and an alcohol-containing solution with stirring for 10-600 seconds to obtain a mixed solution, immediately feeding the mixed solution into a polymerization vessel containing an organoaluminum compound, and copolymerizing ethylene and an .alpha.-olefin, or ethylene, an .alpha.-olefin and a non-conjugated diene compound in the polymerization vessel. According to this process, the activity of polymerization catalyst can be maintained at a high level, no by-product of the reaction of the vanadium compound and the alcohol is deposited as precipitate in the apparatus and no such additional operations as bubbling is necessary.

Abstract: A process for the production of a homogeneous polyethylene comprising contacting a mixture comprising ethylene, one or more alpha-olefins, and one or more unconjugated dienes, under polymerization conditions, with a catalyst system comprising:(a) a catalyst precursor, in independent or prepolymer form, consisting of vanadium (acetylacetonate).sub.3 ;(b) optionally, a support for said precursor;(c) a cocatalyst consisting of an alkylaluminum halide having the formula AlR.sub.(3-a) X.sub.a wherein each R is independently alkyl having 1 to 14 carbon atoms; each X is independently chlorine, bromine, or iodine; and a is 1 or 2; and(d) a promoter, which is a chlorinated ester having at least 2 chlorine atoms; a saturated or unsaturated aliphatic halocarbon having at least 3 carbon atoms and at least 6 halogen atoms; or a haloalkyl substituted aromatic hydrocarbon wherein the haloalkyl substituent has at least 3 halogen atoms.

Abstract: An olefin copolymer is prepared by copolymerizing ethylene, an .alpha.-olefin and, optionally a diene having non-conjugated double bonds by solution polymerization in the presence of:(a) an organoaluminum compound,(b) a vanadium compound in the oxidation state from +3 to +5, and(c) an activator in a molar ratio of from 0.5 to 100 relative to vanadium of said vanadium compound, and an activator of a 2-halomalonic ester substituted by an aromatic group and having the formula ##STR1## wherein X=F, Cl, Br or I, Ar is an aromatic radical which is unsubstituted, monosubstituted or polysubstituted by alkyl or alkoxy groups and which is bound to the central carbon atom either directly or by an intervening carbonyl group; and R.sub.1 and R.sub.2 are hydrocarbon radicals having from 1 to 20 carbon atoms.

Abstract: This catalyst consists of the reaction product, with at least one organomagnesium compound and/or organolithium compound R.sup.1 Li (R.sup.1 =alkyl) or ArLi (Ar=phenyl or benzyl), of the reaction product of (Cp).sub.2 MX.sub.2 Li(OR.sub.2).sub.2 (M=lanthanide, Sc, Y; (Cp)=optionally substituted cyclopentadienyl; and R=alkyl), with at least one bidentate ligand, such as .beta.-diketone or .beta.-keto imine CZ.sub.3 COCHZCDCZ.sub.3, Z selected from halogen, alkyl and H, D=O, NH or NR.sup.3 (R.sup.3 =alkyl or aryl); and phosphorus ylid R.sup.2.sub.3 P.dbd.CA--CO--R.sup.2, R.sup.2 chosen from alkyl and aryl; A=alkyl or H. It advantageously takes the form of a solution at least partially containing an aromatic hydrocarbon. The process for the polymerization of ethylene may be carried out at 20.degree.-250.degree. C. at a pressure which may range up to approximately 200 bars, in solution or in suspension in an at least C.sub.

Abstract: In an improved process for producing elastomeric ethylene-propylene copolymers with a propylene content comprised within the range of from 22 to 38% by weight and a content of residual chlorine, coming from the co-catalyst, lower than 300 parts per million parts, the polymerization is carried out in suspension in the monomers in the liquid state, with vanadium triacetylacetonate and alkyl-Al compounds, and the obtained polymer is recovered without any washing steps.