Abstract: The invention relates to a method for the production of copolymer based on ethylene by continuous copolymerization of ethylene and comonomer in a reactor in the presence of a catalyst. In this method, in a first step of the copolymerization, a mixture comprising ethylene and comonomer of such a composition that a copolymer-containing coating deposits in the reactor is metered into the reactor and/or generated in the reactor, and, in a second step, the concentration of the comonomer in the metered-in mixture and/or in the mixture generated in the reactor is reduced sufficiently and/or the concentration of the ethylene in the metered-in mixture and/or in the mixture generated in the reactor is increased sufficiently that the coating is removed from the reactor either partially or completely. The method has the advantage that the production of copolymer does not have to be interrupted during cleaning of the reactor.

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 metallocene catalyst and dinitrogen monoxide in amounts sufficient to reduce the electrostatic charge in the polymerization medium. Also provided is a process for reducing electrostatic charge in the production of polyolefins by introducing dinitrogen monoxide into the polymerization medium.

Abstract: An ethylene polymerization process is disclosed. The polyethylene has a long-chain-branching index (LCBI) of 1 or greaster. The process uses a single-site catalyst that contains a boraaryl ligand. The catalyst is alkylated with triisobutyl aluminum.

Abstract: A process for producing a polymer of an &agr;-olefin which comprises polymerizing an &agr;-olefin having at least 4 carbon atoms in the presence of a catalyst for producing polymers of olefins which comprises (A) a specific metal compound and (B) at least one compound selected from (b-1) an organoaluminum oxy compound and (b-2) an ionic compound. The polymer of an &agr;-olefin is useful as a component of lubricant.

Abstract: Propene terpolymers consist of from 80 to 99.5 mol % of structural units derived from propene, from 0.1 to 15 mol % of structural units derived from ethene or a C4-C6-1-olefin (I) and from 0.

Abstract: A thermoplastic elastomer composition comprising 5 to 95 wt % of the following (A) and 5 to 95 wt % of the following (B), wherein the flowability index I according to a test for flow properties with a capillary rheometer is 1.

Abstract: The present invention provides an olefin polymer having a narrow molecular weight distribution and a specific molecular weight, an olefin polymer having a functional group introduced at the terminal, a tapered polymer containing a segment wherein monomer composition continuously changes in the polymer chain, an olefin polymer having different segments which are bonded to each other, and a process for preparing these polymers. The olefin polymers of the invention are polymers of olefins of 2 to 20 carbon atoms and have a number-average molecular weight of not less than 500 and Mw/Mn of not more than 1.5.

Abstract: A metallocene catalyst may be temporarily and reversibly passivated by contact with an effective amount of an unsaturated hydrocarbon passivating compound.

Abstract: Provided is a method of polymerizing olefins and a catalyst system for polymerizing olefins. In one embodiment, the method of polymerizing olefins comprises combining under polymerization conditions an olefin monomer; an activator; and a bridged metallocene compound comprising two Cp groups and a trivalent bridging group (A); the group (A) comprising at least one A moiety and at least three linkages between the A moiety and the two Cp ligands; wherein the Cp groups are independently selected from the group consisting of cyclopentadienyl, tetrahydroindenyl, indenyl, heterocyclic analogues thereof and substituted analogues thereof.

Abstract: The present invention relates to a polymerizable composition comprising a) at least one ethylenically unsaturated monomer and b1) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl and a free radical initiator or b2) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ether. Further aspects of the present invention are a process for polymerizing ethylenically unsaturated monomers, the (co)polymers obtainable by this process and the use of multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyls in combination with a free radical initiator, or a multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ethers for controlled polymerization. In a particularly preferred embodiment at least one additional heating step at a temperature from 140 to 280° C. is applied after polymerization is completed.

Abstract: Long-chain, branched, propylene-based polymers, of which the melt index and the molecular weight distribution and the melt tension and the limiting viscosity both satisfy specific requirements, have good physical properties that are comparable to or better than those of conventional propylene-based polymers. They have good melt workability and are favorable to large-size blow molding and extrusion foaming. They are favorably used as miscibility improvers for propylene homopolymers and propylene-based copolymers.

Abstract: Reagents to cause swelling of coarsely ground vulcanized rubber, and a method of using the reagents is disclosed. Reagents which cause rubber to swell but which do not attack or react with rubber include various hydrocarbons, ketones and lactones. Specifically useful are benzene, cyclohexanone, cyclohexane, toluene, xylene, hexane, heptane, acetone, gasoline, paramethadione, ethyl acetate, methyl ethyl ketone and amyl acetate. It is taught that specific reagents work most effectively with specific types of rubbers, and that mixtures of reagents, preferably reagents having the same polarity, may be used. The reagent of the present invention is mixed with the coarsely ground rubber powder for about five minutes or more, causing the rubber particles to approximately double in size. Preferably, the reagent is substantially fully absorbed by the rubber. The swollen rubber is then suitable for further processing, namely, grinding into a superfine powder.

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: Silica powders and mixed silica-oxide powders and methods of preparing such powders for use as catalyst supports for polymerization processes.

Abstract: This invention relates to olefin polymerization processes suitable for limiting or eliminating aromatic solvents or diluents. The invention processes can be conducted by contacting polymerizable olefin monomers with catalyst complexes of Group 3-11 metal cations and noncoordinating or weakly coordinating anions bound directly to the surfaces of finely divided substrate particles or to polymer chains capable of effective suspension or solvation in polymerization solvents or diluents under polymerization conditions. These processes minimize problems associated with using largely insoluble organometallic or organometalloid catalysts and cocatalysts in aliphatic, solution, or diluent polymerization processes.

Abstract: A process for the gas-phase (co-)polymerization of olefins in a fluidized bed reactor using a metallocene catalyst in that the polymerization is preformed in the presence of a process aid additive selected from at least one of 1) a polysulfone copolymer, 2) a polymeric polyamine, or 3) an oil-soluble sulfonic acid.

Abstract: This application discloses triphenyl carbenium NCA's as catalyst activators for a class of asymmetrically bridged hafnocene catalyst precursors. These catalyst precursors are activated into olefin polymerization catalysts and are suitable for gas, solution, and slurry-phase polyermization reactions. The disclosed bridge is methylenyl- or silanylenyl-based and is optionally, alkyl or aryl substituted. The catalytic activity of the disclosed hafnocene catalyst precursors is substantially enhanced over identical catalysts that are activated with other activators.

Abstract: A catalyst precursor compound useful for the polymerization of olefins. The compound comprises a metal atom and two &pgr;-bonded aromatic ring systems which are bridged by being linked to adjacent members of a ring structure in cis fashion.

Abstract: A polymerization process comprises contacting one or more olefinic comonomers in the presence of at least a high molecular weight catalyst and at least a low molecular weight catalyst in a single reactor; and effectuating the polymerization of the olefinic comonomers in the reactor to obtain an olefin polymer. Preferably, both catalysts have the ability to incorporate a substantially similar amount of comonomers in the olefin polymer. The polymers produced by the process may have a relatively higher level of long chain branching while maintaining a relatively narrow molecular weight distribution, i.e., MWD less than about 6. These interpolymers may exhibit processability similar to or better than LDPE but have physical properties similar to metallocene catalyzed polymers.

Abstract: A process for making ethylene copolymers is disclosed. Ethylene copolymerizes with an &agr;-olefin in the presence of a catalyst system comprising an activator and a silica-supported, bridged indenoindolyl metal complex having “open architecture.” The supported complex incorporates comonomers with exceptional efficiency, and the process gives ethylene copolymers having high molecular weights (Mw>100K) and very low densities (<0.910 g/cm3). Open architecture catalysts that include bridging through the indolyl nitrogen of the indenoindolyl framework are also described.

Abstract: The sealability of a thermoplastic, mono- or multi-layer film having an irradiated sealing layer comprising a polyethylene and/or an ethylene-x-olefin copolymer with a density ≧0.915 g/cm3 is improved by corona treating said sealing layer. The integrity of the obtained sealed container is maintained under pasteurizing or cook-in conditions.

Abstract: The invention refers to a linear, isotactic polymer which has a structure of one or several C2 to C20 olefins, of which the isotacticity due to a statistic distribution of stereoscopic errors in the polymer chain, is within the range of from 25 to 60% of [mmmm] pentad concentration, the polymer having a mean molecular weight Mw within the range of from 100,000 to 800,000 g/mol and a Tg of from −50 to 30° C.

Abstract: Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LLDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I2 and Mw/Mn. The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative linear ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I10/I2,≧5.63, a molecular weight distribution, Mw/Mn, defined by the equation: Mw/Mn≦(I10/I2)−4.

Abstract: The present invention concerns a polyethylene composition particularly suitable for film blowing. The invention also concerns a process for the production thereof. The composition comprises a low molecular weight portion having a density of more than 960 kg/m3 and a high molecular weight portion. The polyethylene composition has a density of about 925-940 kg/m3 and a melt flow rate in the range of MFR21, from 5 to 40 g/10 min. A polyethylene film blown from the polyethylene composition exhibits a tensile strength at yield in transverse direction at least 15 MPa, a 1% secant modulus in machine direction at least 300 MPa and in transverse direction at least 400 MPa, and a dart drop of at least 5 g/&mgr;m.

Abstract: A process for producing terpolymers of propylene, comprising a) feeding into a slurry reactor a reaction mixture containing 50-85 w-% of propylene, 1-10 w-% of ethylene, 15-40 w-% of another C4-C8 alpha-olefin, a catalyst system maintaining olefin polymerization at said temperature conditions, and optionally hydrogen, b) polymerizing said reaction mixture at a temperature of lower than 70° C. a sufficient time to obtain a propylene terpolymer amounting to 50-99 w-% of the end product, c) transferring said reaction mixture into a gas phase reactor operating at a pressure of higher than 5 bars, preferably higher than 10 bars, optionally adding 0-30 w-% of ethylene, 0-10 w-% of another C4-C8 alpha-olefin, 0-40 w-% of propylene and optionally hydrogen, and d) continuing polymerization in said gas phase reactor for obtaining a propylene terpolymer amounting to 1-50 wt-% of the end product. The terpolymer has a melting temperature a less than 135° C., preferably less than 132° C.

Abstract: A thermoplastic elastomer composition comprising 5 to 95 wt % of the following (A) and 5 to 95 wt % of the following (B), wherein the flowability index I according to a test for flow properties with a capillary rheometer is 1.35 or more: (A) an ethylene-&agr;-olefin copolymer having a tensile stress M100 measured according to JIS-K-6251 of 2.5 MPa or less, (B) a polyolefin-based resin having a tensile stress M100 measured according to JIS-K-6251 of 2.5 MPa or more.

Abstract: Silica powders and mixed silica-oxide powders and methods of preparing such powders for use as catalyst supports for polymerization processes.

Abstract: One or more oligomers of an olefin are prepared in the presence of a single-site catalyst. Preferably, the olefin is an &agr;-olefin, and the oligomers are a poly-alpha-olefin (PAO). The PAO so prepared is completely or substantially free of tertiary hydrogen resulting from isomerization. Consequently, the PAO possesses improved biodegradability, improved oxidation resistance, and/or a relatively higher viscosity index. The PAO has many useful applications, such as a component of a lubricant.

Abstract: Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I2and Mw/Mn. The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative linear ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I10/I2, ≧5.63, a molecular weight distribution, Mw/Mn, defined by the equation: Mw/Mn≦(I10/I2)−4.

Abstract: Catalyst compositions and methods, useful in polymerization processes, utilizing at least two metal compounds are disclosed. At least one of the metal compounds is a Group 15 containing metal compound and the other metal compound is preferably a bulky ligand metallocene-type catalyst. The invention also discloses a new polyolefin, generally polyethylene, particularly a multimodal polymer and more specifically, a bimodal polymer, and its use in various end-use applications such as film, molding and pipe.

Abstract: A polymerization process comprises (1) contacting at least one polymerizable monomer in the presence of a metal catalyst in a reactor; (2) effectuating polymerization of the monomer; (3) adding a substituted olefin having at least one polar group to the reactor. The substituted olefin is different from the monomer. Vinyl-terminated macromers preferably are generated which can be homopolymerized or copolymerized with the monomer by the metal catalyst. A polymer of an olefin monomer and a substituted olefin comprising a backbone and a plurality of side chains. The polymer is characterized by an Rv of greater than about 0.85, where Rv is a measure of the relative number of vinyl groups in the polymer. In some polymers, the vinyl endgroups are transformed to other useful end groups.

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.

Abstract: Catalyst components for the preparation of ethylene (co)polymers capable to produce polymers with high bulk density, to avoid the problems of formation of fines and that have a high activity are provided. Said catalyst components are characterized by comprising a non-stereospecific solid catalyst component, comprising a titanium compound and a magnesium dihalide, which is pre-polymerized with an alpha olefin CH2═CHR1 wherein R is a C1-C8 alkyl group, to such an extent that the amount of the &agr;-olefin pre-polymer is up to 100 g per g of said solid catalyst component.

Abstract: A copolymer of ethylene and a higher alpha olefin, preferably 1-hexene, can be produced using an activated chromium containing catalyst system and a cocatalyst selected from the group consisting of trialkylboron, trialkylsiloxyaluminum, and a combination of trialkylboron and trialkylaluminum compounds. The polymerization process must be carefully controlled to produce a copolymer resin having an exceptionally broad molecular weight distribution, extremely high PENT ESCR values, and a natural branch profile that impacts branching preferably into the high molecular weight portion of the polymer. The resulting copolymer resin is especially useful in high stiffness pipe applications.

Abstract: A novel liquid phase polymerization process for preparing a polyolefin product having preselected properties is disclosed. The process includes the steps of providing a liquid feedstock which contains an olefinic component and a catalyst composition consisting of a stable complex of BF3 and a complexing agent therefor. The feedstock may comprise any one or more of a number of olefins including branched olefins such as isobutylene, C3 to C15 linear alpha olefins and C4 to C15 reactive non-alpha olefins. The feedstock and the catalyst composition are introduced into a residual reaction mixture recirculating in a loop reactor reaction zone provided in the tube side of a shell and tube heat exchanger at a recirculation rate sufficient to cause intimate intermixing of the residual reaction mixture, the added feedstock and the added catalyst composition.

Abstract: The instant invention is a method for optimizing material transformation that includes the following six steps. The first step is to identify at least one physical variable that affects performance of a continuous unit operation for the material transformation. The second step is to select an initial set point of the at least one physical variable. The third step is to continuously perform the unit operation to produce a transformed material. The fourth step is to analyze the product to determine at least one component of interest of the transformed material. The fifth step is to select a subsequent set point of the at least one physical variable based on the analysis of the fourth step. The last step is to repeat steps three to five a sufficient number of times to optimize the unit operation.

Abstract: 1 A metallocene compound of general formula (I): LGZMXp, wherein L is a divalent group, Z is a moiety of formula (II), wherein R3 and R4 are selected from hydrogen and hydrocarbon groups; A and B are selected from S, O or CR5, wherein R5 is selected from hydrogen and hydrocarbon groups, either A or B being different from CR5; G is a moiety of formula (III), wherein R6, R7, R8 and R9 are selected from hydrogen and hydrocarbon groups, M is an atom of a transition metal, X is selected from a halogen atom, a R10, OR10, OSO2CF3, OCOR10, SR10, NR102 or PR102 group, wherein the substituents R10 is hydrogen and a hydrocarbon group; p is an integer from 0 to 3.

Abstract: A novel liquid phase polymerization process for preparing a polyolefin product having preselected properties is disclosed. The process includes the steps of providing a liquid feedstock which contains an olefinic component and a catalyst composition consisting of a stable complex of BF3 and a complexing agent therefor. The feedstock may comprise any one or more of a number of olefins including branched olefins such as isobutylene, C3 to C15 linear alpha olefins and C4 to C15 reactive non-alpha olefins. The feedstock and the catalyst composition are introduced into a residual reaction mixture recirculating in a loop reactor reaction zone provided in the tube side of a shell and tube heat exchanger at a recirculation rate sufficient to cause intimate intermixing of the residual reaction mixture, the added feedstock and the added catalyst composition.

Abstract: This invention relates to a process for the synthesis of addition polymers containing branches upon branches and having a polymerizable olefin end group by a convenient one-pot polymerization of selected vinyl monomers with chain polymerization initiators and a method to provide olefinic end groups by chain termination agents; and polymers produced thereby characterized by branch-on-branch structure and lower inherent viscosity than heretofore possible.

Abstract: Ethylene homopolymers and copolymers having a broad molecular distribution, excellent toughness and improved processability. These polymers may be prepared by use of a single metallocene catalyst system in a single reactor in the gas phase. These polymers of density typically 0.85-0.95 are defined in particular by their melt strength (MS) and long chain branching (LCB) characteristics and are particularly suitable for use in low density film applications.

Abstract: In a process for the gas-phase polymerization of &agr;-olefins at from 20 to 130° C. and pressures of from 1 to 100 bar, the polymerization is carried out in a tubular reactor having a length:diameter ratio of >100 and the growing polymer particles pass through the tubular reactor in its longitudinal direction without a significant part of the polymer particle stream being circulated.

Abstract: A process for preventing polymeragglomeration and for controlling the density of copolymer produced by an alpha-olefin copolymerization process in a polymerization reactor, wherein the ratio of the flow rates of introduction of the comonomer(s) to the monomer is kept constant.

Abstract: A process for the polymerisation and copolymerisation of olefins is disclosed, comprising contacting the monomeric olefin under polymerisation conditions with a polymerisation catalyst or catalyst system which comprises (a) a source of a Group VIII metal; (b) a bidentate phosphine ligand having the formula (R1)(R1)P—X—P(R1)(R1), where each R1 is independently selected from a phenyl group or a substitued phenyl group with the proviso that at least one of the R1 groups is a phenyl group having at least one ortho substituent, and X is a bridging group of the structure —[N]x—[P]9—[N]— where x and y are independently 0 or 1, or —C(R4)2—where R4 may be the same or different and is hydrogen or a monovavlent hydrocarbyl, substituted hydrocarbyl or hetero-hydrocarbyl group; and optionally (c) a promoter.

Abstract: Elastic ethylene polymers are disclosed which have processability similar to highly branched low density polyethylene (LDPE), but the strength and toughness of linear low density polyethylene (LLDPE). The polymers have processing indices (PI's) less than or equal to 70 percent of those of a comparative linear ethylene polymer and a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a traditional linear ethylene polymer at about the same I2 and Mw/Mn. The novel polymers can also have from about 0.01 to about 3 long chain branches/1000 total carbons and have higher low/zero shear viscosity and lower high shear viscosity than comparative linear ethylene polymers. The novel polymers can also be characterized as having a melt flow ratio, I10/I2, ≧5.63, a molecular weight distribution, Mw/Mn, defined by the equation: Mw/Mn≦(I10/I2)−4.

Abstract: Disclosed is a novel ethylene copolymer by copolymerizing an ethylene and at least one comonomer selected from a compound represented by the formula H2C═CHR wherein R is an alkyl group or an aryl group, and a diene, by slurry polymerization process in the presence of a solid catalyst system comprising a support, a transition metal compound and an activator capable of converting the transition metal compound into a catalytically active transition metal complex. The produced copolymer has a density of from 0.870 to 0.

Abstract: A polymer of ethylene as a first monomeric component, with a high carbon number linear alpha olefin having at least five carbon atoms as a second monomeric component. At least one of the monomeric components is Fischer-Tropsch derived so that it includes at least one other olefinic component. A process for producing the polymer is also provided.

Abstract: Group 4 metal complexes of the constrained geometry type, catalysts derived therefrom, and polymerization processes using the same, characterized by an alkaryl-substituted silane bridging group are disclosed.

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: 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.

Abstract: The present invention provides an ethylene resin sealant for a laminated film, which is excellent in low-temperature heat-sealing properties, hot tack properties, impact resistance, tearability and extrusion properties. This ethylene resin sealant for a laminated film comprises an ethylene/&agr;-olefin copolymer having the following properties: the density is in the range of 0.880 to 0.920 g/cm3; the melt flow rate (MFR) at 190° C. under a load of 2.16 kg is in the range of 0.1 to 5.0 g/10 min; the decane-soluble component fraction (W) at room temperature and the density (d) satisfy the relation W<80×exp(−100(d−0.88))+0.1; the flow index (FI), which is defined as a shear rate at which the shear stress of said copolymer in a molten state at 190° C. reaches 2.4×106 dyne/cm2, and MFR satisfy the relation FI>75'MFR; and the melt tension (MT) at 190° C. and MFR satisfy the relation 5.5×MFR−0.65>MT>2.2×MFR−0.84.