Abstract: The present invention relates to a process for continuous gas phase polymerization of olefin(s) in a reactor containing a fluidized bed, consisting of a cylinder with a vertical side wall and of a desurging or disengagement chamber mounted above the said cylinder, characterized in that the fluidized bed occupies at least all of the cylinder with a vertical side wall of the reactor.

Abstract: This invention relates to a polymerization process comprising combining an olefin in the gas or slurry phase with a spray dried catalyst comprising an activator, a particulate filler and a metal catalyst compound.

Abstract: A solid catalyst component for olefin polymerization superior in shatter resistance and narrowness of particle size distribution, is provided, which component is prepared by spraying a mixture of Mg compound with an alcohol in a molten state, in a column; cooling the inside of the column; to obtain a component (B); partly removing the alcohol from (B), to obtain a solid component (C); contacting a halogen-containing Ti compound and an electron donor with (C); to obtain (D); contacting (D) with a halogen-containing Ti compound; in the above process, specifying the composition formulas of (A), (B) and (C); specifying the X-ray diffraction spector of (C) in comparison of that of (B); and contacting (C) with a halogen-containing Ti compound and an electron donor using an aliphatic hydrocarbon of a specified b.p., in a specified temperature.

Abstract: A process for treatment of metathesis catalysts for olefins comprises sending the particles of catalysts through at least one vibratory helicoidal conveyor, subject the particles over at least a portion of their path and preferably over a large portion of their path to a temperature profile, and bringing the particles into contact with at least one fluid over at least a portion of their path. A vibratory helicoidal lifting device (12) makes it possible to regenerate metathesis catalysts for olefins: it comprises a combustion zone (14) and a calcination zone (15), as well as a preheating zone, a zone for stripping hydrocarbons and a zone for cooling the catalyst.

Abstract: The subject-matter of the present invention is thus a process for starting up a gas phase olefin polymerisation reaction carried out using a Ziegler-Natta type catalyst based on a transition metal in a fluidized-bed reactor, through which passes a reaction gas mixture comprising the olefin, an inert gas, hydrogen and optionally at least one comonomer and which operates under conditions of temperature and pressure which make it possible to start up the polymerization, characterized in that the partial pressure of the olefin and the rate of introduction of catalyst into the reactor are increased whilst maintaining the ratios of the partial pressures of the olefin to the hydrogen and to the optional comonomer or comonomers substantially constant.

Abstract: In gas phase fluid bed polymerization processes, operation can be achieved over wider ranges of fluidizing gas velocities without incurring undue energy costs by adjusting the pressure drop through the grid below the bed to provide a ratio of pressure drop through the grid to pressure drop through the grid and bed above about 0.15:1. The range of fluidizing gas velocities can enhance the practicality of operating the processes over varying bed heights while reducing the risk of forming deposits of polymer. The processes of the invention are particularly useful to accommodate start-ups, catalyst transitions and shutdowns.

Abstract: There is provided a polymerization of a sticky polymer in the presence of a catalyst under polymerization conditions using carbon black as the inert particulate material, the improvement comprises conducting said polymerization in the presence of a carbon black that has been treated with a sulfur donor and/or an oxidizing agent.

Abstract: A process is disclosed for removing particulate product from a fluidized bed reactor to optimize, within the constraints of the product removal cycle, conservation of gas in which the product is entrained. Data are compiled on the time required for equalizing pressure between product discharge tanks, and these data are used to determine the optimum times for various valves to be open. Product movement steps and equalization steps can be performed simultaneously.

Abstract: A process for starting a polymerization of butadiene to produce polybutadiene in a gas phase reactor having a seed bed which comprises (i) passivating the reactor and the seed bed by introducing an aluminum alkyl having a concentration ranging from about 2,000 to 20,000 ppm and (ii) feeding the catalyst and co-catalyst to the reactor before the addition of the butadiene.

Abstract: A process, particularly a gas phase fluidised bed process, for the production of polymers avoids formation of sheets or chunks within the reactor, without the need to use antistatic agents, which can reduce the activity of the catalyst or alter the characteristics of the yielded product. According to the invention, a device generates a corona discharge in the polymerisation reactor during the polymerisation process; an AC voltage difference is applied between the elements which constitute the discharging pair of the device.

Abstract: The present invention relates to a process for the polymerization of monomers utilizing a bulky ligand hafnium transition metal metallocene-type catalyst compound, to the catalyst compound itself and to the catalyst compound in combination with an activator. The invention is also directed to an ethylene copolymer composition produced by using the bulky ligand hafnium metallocene-type catalysts of the invention, in particular a single reactor polymerization process. The hafnocene compound comprises at least one ligand substituted with at least one linear or iso alkyl substituent of at least 3 carbon atoms, and the catalyst system may comprise a mixture of two or more such hafnocenes.

Abstract: A process of producing polyethylene, the process comprising copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms in the presence of a chromium-based catalyst in a main polymerization reactor and, in a gas-phase preliminary reactor upstream of the main polymerization reactor, chemically treating the chromium-based catalyst with at least one treatment agent prior to introduction of the catalyst into the main polymerization reactor and releasing from the preliminary reactor waste gases produced during the chemical treatment.

Abstract: The present invention relates to a polymerization process for preparing syndiotactic polystyrenes, which comprises a step of microfluidizing in a microfluidization apparatus both a catalyst mixture consisting of a styrene monomer, a metallocene catalyst and an inert organic solvent and a cocatalyst mixture consisting of a styrene monomer, a cocatalyst and an inert organic solvent, and a step of reacting the microfluidized mixture with a catalyst and a cocatalyst in a reactor. The metallocene catalyst has a bridged structure of a complex of Group IV transition metals such as Ti, Zr, Hf etc. in the Periodic Table and a ligand having one or two cycloalkane dienyl groups such as cyclopentadienyl group, indenyl groups, fluorenyl group, and derivatives thereof. The reactor is a well stirred reactor equipped with agitating blades therein to mix the reactants well.

Abstract: The present invention relates to an improved catalyst delivery method for introducing a supported bulky ligand metallocene-type catalyst system to a reactor for polymerizing one or more olefin(s). In particular, the invention provides for a method of introducing a supported metallocene-type catalyst system into a polymerization reactor by and in the presence of a carrier solution of an antistatic agent and a liquid diluent. Also, the invention is directed toward a catalyst feeder for use in a polymerization process.

Abstract: Organometallic complexes having two phosphinimine ligands and at least one activatable ligand are catalyst components for olefin polymerization. Preferred polymerization systems are prepared by combining the organometallic complexes with an ionic activator and/or an alumoxane. Preferred catalyst components contain titanium, zirconium, or hafnium and are activated with an ionic activator to form catalysts for ethylene polymerization.

Abstract: A supported catalyst for the polymerization of olefins, especially ethylene, has at least two catalyst components having different propagation and/or termination constants. Each catalyst component must have at least one phosphinimine ligand. The polymer produced according to this invention has a broad molecular weight distribution. Catalysts according to this invention have a very surprising and desirable hydrogen response.

Abstract: An organometallic complex of a group 4 metal having a cyclopentadienyl ligand and a heterosubstituted phosphinimine ligand is a catalyst component for olefin polymerization. The heterosubstituted phosphinimine ligand may be conveniently and inexpensively synthesized using readily available precursors which are comparatively non-pyrophoric. The resulting catalysts are highly active for ethylene copolymerization, particularly when activated with an alumoxane or ionic activator.

Abstract: A novel process for producing homopolymers and copolymers of ethylene which involves contacting ethylene and/or ethylene and at least one or more olefin comonomer(s) under polymerization conditions with a Ziegler-Natta type catalyst substantially free of internal electron donor, trimethylaluminum and at least one compound containing at least one carbon-oxygen-carbon linkage (C—O—C) of the formula R1—O(—R2—O)n—R3 where n ranges from 0 to 30, and R1, R2 and R3 independently contain from 1 to 30 carbon atoms and from 0 to 30 heteroatoms of an element, or mixtures thereof, selected from Groups 13, 14, 15, 16 and 17 of the Periodic Table of Elements, and further wherein R1, R2 and/or R3 can be linked and form part of a cyclic or polycyclic structure. Also provided are films and articles produced therefrom.

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

Abstract: A continuous process for the manufacture of olefin polymers in a continuous gas phase polymerization reaction wherein monomer, after passage through the fluidized bed, is cooled to a temperature below its dew point to produce a mixture of cold gas and liquid. All or part of the cold gas is introduced into the bottom of the reactor to serve as the fluidizing gas stream for the fluidized bed. Cold liquid separated from the mixture is warmed to form a heated fluid by passing in indirect heat exchange relation with the fluidized bed and the heated fluid is then injected directly into the bed; combined with the fluidizing gas stream; sprayed on top of the bed or combined with gaseous monomer removed from the fluidized bed for cooling.

Abstract: There is provided a process for the gas phase production of an ethylene-propylene or ethylene-propylene-diene rubber in the presence of a single site or single-site like catalyst (e.g., metallocene) catalyst system and an inert particulate material comprising pretreating the inert particulate material with trialkylaluminum (e.g., tri-isobutylaluminum) before commencing polymerization.

Abstract: A continuous gas fluidized bed process for the polymerization of olefins, especially ethylene, propylene, or mixtures thereof with other alpha-olefins by cooling the recycle gas stream to condense some liquid (e.g., a comonomer), separating at least part of the liquid and spraying it under pressure through a nozzle (1) directly into the fluidized bed by pressurizing the liquid and feeding it to a spray nozzle (1) having a mechanical device (6) for atomizing the liquid, under conditions such that the spray is formed within a spray-forming zone (5) of the nozzle outlet. The spray-forming zone (5) is preferably shielded from the fluidized bed particles by a wall or walls which can be, for example, a tube or a plate. Also described is a nozzle having two or more series of outlets, each series being fed and controlled independently to enable improved turn-up/turn-down of the liquid supply to the bed.

Abstract: The present invention teaches the use of particular soluble metallocene catalysts to produce stereoregular polymers in gas phase polymerizations wherein the catalysts are fed into a particular lean zone in the reactor. The metallocene catalysts are bridged bis(substituted indenyl) compounds.

Abstract: Modified polypropylenes of improved processability are produced by a continuous method by absorptively charging polypropylene particles at 20° to 120° C. with a gas mixture, which contains oxygen and bifunctional, unsaturated monomers, and melting the mixture. The modified polypropylenes of improved processability as well as mixtures with unmodified polypropylenes are suitable for the production of films, sheets, fibers, panels, coatings, pipes, hollow objects and foamed materials.

Abstract: A novel process for producing homopolymers and interpolymers of olefins which involves contacting an olefin and/or an olefin and at least one or more other olefin(s) under polymerization conditions with a Ziegler-Natta catalyst and dinitrogen monoxide in an amount sufficient to reduce the electrostatic charge in the polymerization medium. Also provided is a process for reducing electrostatic charge in the polymerization of an olefin by adding dinitrogen monoxide.

Abstract: A novel process for producing homopolymers and interpolymers of olefins which involves contacting an olefin and/or an olefin and at least one or more other olefin(s) under polymerization conditions with an olefin polymerization catalyst and dinitrogen monoxide in an amount sufficient to reduce the electrostatic charge in the polymerization medium. Also provided is a process for reducing electrostatic charge in the polymerization of an olefin by adding dinitrogen monoxide.

Abstract: A continuous gas fluidized bed process for the polymerization of olefin monomer(s) wherein the recycled gaseous stream withdrawn from the reactor is divided into two streams (A and B) and that (a) a first stream (A) having been cooled to a temperature at which liquid condenses out is then reintroduced directly into the fluidized bed in the reactor in such a way that, at any time, the condensed liquid is continuously introduced into the bed at a minimum rate of 10 liters of liquid per cubic meter of fluidized bed material per hour, and (b) a second stream (B), which by-passes the above cooling/condensing step, is passed through an exchanger and is then reintroduced into the reactor. The continuous introduction of a liquid into the reactor reduces or even eliminates fouling problems which can be encountered in conventional gas phase olefin polymerization processes.

Abstract: A catalyst composition for the polymerization of olefins is provided. The catalyst composition comprises a mono- or biscycloalkadienyl catalyst precursor comprising at least one protected hydride ligand or protected hydrocarbyl ligand bound to a metal atom plus a cocatalyst. The protected hydride ligand is preferably a borohydride ligand.

Abstract: There is provided a polymerization, especially a gas phase polymerization, of a sticky polymer in the presence of a catalyst under polymerization conditions using carbon black as an inert particulate material, the improvement comprises conducting said polymerization in the presence of a carbon black having a sugar-containing or sugar-derived binder, which carbon black is prepared by heating the carbon black to a temperature of at least about 280° C. for a time sufficient to decompose said sugar-containing or sugar-derived binder prior to polymerization.

Abstract: The disclosed invention relates to a polymerization process comprising contacting ethylene, and optionally, one or more olefinically unsaturated comonomers, with an active supported Group 3, 4, 5, or 6 metallocene catalyst system having an unsubstituted or substituted fused-ring cyclopentadienyl ligand, preferably indenyl or fluorenyl, and a substituted or unsubstituted cyclopentadienyl ligand under gas-phase or slurry polymerization conditions. The process is suitable for the production of high-density polyethylene homopolymers and copolymers. The benefits to industrial practice are both the ease of preparation and low-cost of the precursor metallocene compound and the commercially feasible polymerization activity levels in stable, low fouling level reactor conditions surprisingly associated with it. Additionally, the polymers made under the invention process conditions have narrow molecular weight distributions, low MI, and low values for MIR.

Abstract: Propylene may be polymerized by contacting it with certain iron complexes of selected 2,6-pyridinecarboxaldehydebis(imines) and 2,6-diacylpyridinebis(imines). The polymers produced are useful as molding resins.

Abstract: Liquid catalyst composition is fed to a fluidized bed olefin polymerization reactor through an ultrasonic nozzle, enabling improved control over average catalyst composition droplet size and size distribution, which provides better control over resin particle size. The spray may be surrounded by a shroud of gas which creates a particle lean zone, thus reducing the likelihood of contact by the catalyst composition with existing product particles already suspended in the fluid bed.

Abstract: Organometallic complexes having a phosphinimine ligand, a (non-phosphinimine) heteroligand and at least one activatable ligand are catalyst components for olefin polymerization. Preferred polymerization systems are prepared by combining the organometallic complexes with an ionic activator and/or an alumoxane. Preferred catalyst components contain Ti, Zr or Hf and are activated with an ionic activator to provide ethylene polymerization catalysts.

Abstract: This invention is directed to a process for the preparation of polyolefins from one or more olefinic monomers comprising combining said olefins under olefin polymerization conditions with an organometallic catalyst compound that is activated for olefin polymerization by reaction with at least one Lewis acid aluminum compound of the formula R.sub.n Al(ArHal).sub.3-n, where "ArHal" is a halogenated aryl group, n=1 or 2, and R is a monoanionic group other than a halogenated aryl group. The invention also relates to a polymer produced using the process and to the polymer itself.

Abstract: A process comprising contacting one or more monomers with a catalyst, in the gas phase, under polymerization conditions, in a fluidized bed reactor, with the proviso that the reactor is at least partially cooled internally by the vaporization of a liquid cryogen directly into the reactor.

Abstract: The invention generally relates to a catalyst, particularly a metallocene catalyst and catalyst system useful in the polymerization of olefins into a polymer product. Specifically, a catalyst system with (n-PrCp).sub.2 ZrCl.sub.2 exhibits high catalytic activity.

Abstract: A catalyst system comprises an organometallic complex of a group 4 metal having a ketimide ligand. The organometallic complex preferably also contains a cyclic ligand which forms a delocalized pi-bond with the metal (such as a cyclopentadienyl-type ligand). Preferred organometallic complexes may be activated with a so-called "substantially non coordinating anion" to form a low cost cocatalyst system which is excellent for the preparation of olefin copolymers having both high molecular weight and very low density.

Abstract: A process for the homo- or copolymerization of C.sub.2 -C.sub.8 -alk-1-enes by means of a Ziegler-Natta or a metallocene catalyst system in a stirred bed of finely divided polymer from the gas phase, the transition metal-containing catalyst solid of the Ziegler-Natta or metallocene catalyst system being fed to the reactor by C.sub.2 -C.sub.8 -alk-1-ene metered into the reactor, wherein the transition metal-containing catalyst solid, together with at least some of the C.sub.2 -C.sub.8 -alk-1-ene, is fed to the reactor through one or more pipes which project perpendicularly or virtually perpendicularly from above into the gas space and end above the pulverulent stirred reactor bed.

Abstract: The present invention relates to a gas phase process for the polymerization of monomer(s) utilizing a metallocene catalyst system to produce easy processing polyolefin polymers.

Abstract: Addition of water to a gas phase olefin polymerization reactor in amounts greater than 3 ppmv permits an increase in the level of condensable gas and facilitates operation of the reactor at an elevated dew point by ameliorating electrostatic phenomena in the reactor; the process inhibits sheeting.

Abstract: A process for producing polymer in a gas phase reactor by introducing a stream of monomer and gas into a polymerization zone while providing at least one liquid component in the polymerization zone.

Abstract: A process for homo or copolymerizing propylene, wherein propylene is polymerized in the presence of a catalyst at an elevated temperature in a reaction medium in which a major part of the reaction medium is propylene and the polymerization is carried in at least one CSTR or loop reactor, where the polymerization is carried out at a temperature and a pressure which are above the corresponding critical temperature and the pressure of the reaction medium and where the residence time is at least 15 minutes. The process can also comprise a supercritical loop polymerization before the supercritical stage polymerization or a gas phase polymerization after the supercritical stage polymerization.

Abstract: The present invention provides a process and apparatus for feeding powders such as fine, cohesive, or powdery particulate materials from a low pressure system to a high pressure system. In a preferred embodiment a process and apparatus of pressurizing and feeding carbon black fluff to a polymerization reactor is provided particularly a gas phase fluidized polymerization reactor to provide for a close-coupling of a carbon black reactor to a polymerization reactor.

Abstract: By utilizing the vapor phase polymerization techniques of the present invention, numerous distinct and highly beneficial advantages are realized. For instance, cis-1,4-polyisoprene rubber and high cis-1,4-polybutadiene rubber having a consistent and controllable molecular weight can be easily and practically prepared without utilizing a solvent. The subject invention more specifically discloses a method for vapor phase polymerizing isoprene into cis-1,4-polyisoprene in a process comprising the steps of:(1) charging into a reaction zone said isoprene and a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrachloride, preferably in the presence of at least one ether; wherein the isoprene is maintained in the vapor phase in said reaction zone by a suitable combination of temperature and pressure;(2) allowing said isoprene to polymerize into cis-1,4-polyisoprene at a temperature within the range of about 35.degree. C. to about 70.degree. C.

Abstract: A process for the polymerization of an olefin which employs as the catalyst composition the reaction product of a) a monocycloalkadienyl catalyst precursor; b) an activity enhancing cycloalkadiene; and c) an activating cocatalyst is disclosed.

Abstract: The invention relates to a polymerization catalyst for alpha-olefins and a process for polymerizing alpha-olefins. The catalyst comprises a component having a transition metal compound supported on a carrier and an aluminoxane. The carrier may be pre-treated with an organometallic compound, a halogen-containing silicon compound or an aluminoxane. Alternatively, the above two catalyst components are subjected to preliminary polymerization of olefins. The catalyst of this invention enables the production of a spherical polymer having a good particle size distribution, an excellent bulk density and a narrow molecular weight distribution in a slurry polymerization method or a vapor-phase polymerization method, particulary the vapor-phase polymerization method. When applied to the copolymerization of at least two olefins, the catalyst has excellent polymerization activity such that an olefin copolymer having a narrow molecular weight distribution and a narrrow composition distribution is obtained.

Abstract: The present invention teaches a process for controlling a continuous gas phase (exothermic) process operating in condensing mode (e.g. polymerization) with a selected temperature for the reactor bed or outlet and with a temperature differential between the reactor inlet and the reactor bed or outlet by controlling the heat transfer provided by the heat exchanger in the recycle line to maintain the selected reactor bed temperature or outlet temperature while simultaneously controlling a condensable liquid feed rate to maintain the temperature differential.

Abstract: A process to produce high melt flow propylene polymer comprises polymerizing propylene in the presence of a titanium-containing, magnesium-containing, high activity catalyst and an aluminum alkyl cocatalyst in a gas phase system which uses condensed liquid to control temperature wherein the external catalyst modifier is a tetraalkylorthosilicate, preferably tetraethylorthosilicate, at process conditions of temperature, hydrogen concentration, and Si/Mg, Al/Mg and Al/Si atomic ratios, to produce a high melt flow propylene polymer at high yield.

Abstract: A process for producing an olefin polymer, which comprises contacting at least two olefin monomers under polymerization conditions with a catalyst composition comprising A) an aluminoxane-impregnated support prepared by contacting an aluminoxane with an inert carrier material and heating to a temperature of at least about 80.degree. C.; B) a metallocene of the formula:(L).sub.y (L')MY.sub.(x-y-1)wherein M is a metal from groups IIIB to VIII of the Periodic Table; each L and L' is independently a cycloalkadienyl group bonded to M; each Y is independently hydrogen, an aryl, alkyl, alkenyl, alkylaryl, or arylalkyl radical having 1-20 carbon atoms, a hydrocarboxy radical having from 1-20 carbon atoms, a halogen, RCO.sub.2 --, or R.sub.2 N--, wherein R is a hydrocarbyl group containing 1 to about 20 carbon atoms; y is 0, 1, or 2; x is 1, 2, 3, or 4; and x-y.gtoreq.1; C) a bulky aluminum alkyl of the formula:AlR.sup.1.sub.x R.sup.2.sub.(3-x)wherein R.sup.

Abstract: A gas phase fluidized bed process is described for producing ethylene polymers having improved processability and an MWD of less than about 2.9. Multiple reactors in series or parallel may be used to produce in-situ blended polymers. Each reactor can separately have a constrained geometry catalyst or a conventional Ziegler-Natta catalyst as needed for obtaining in-situ blended polymer with the desired properties as long as there is a constrained geometry catalyst in at least one reactor. Olefin polymers can be produced according to this invention which have low susceptibility to melt fracture, even under high shear stress conditions.