Abstract: A process for the preparation of a poly(&agr;-olefin) copolymer is disclosed wherein the process comprises polymerizing at least one &agr;-olefin, and at least one bulky olefin, in the presence of hydrogen and a catalytically effective amount of catalyst comprising the product obtained by combining a metallocene procatalyst with a cocatalyst, ligand (Cp2R2p) and bridging group R3 contains at least two bulky groups.

Abstract: A process as disclosed for producing a low density polyethylene using a particle form polymerization process and a titanium-containing catalyst wherein the ratio of comonomer to ethylene is at least about 1:1 and the titanium-containing catalyst is a special catalyst which has been pretreated with an organometallic reducing agent.

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 multi-functional 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: A process is disclosed for the preparation of a poly(&agr;-olefin) polymer wherein the process comprises polymerizing at least one &agr;-olefin in the presence of hydrogen and a catalytically effective amount of catalyst comprising the product obtained by combining a metallocene catalyst with a cocatalyst, the metallocene catalyst being at least one meso compound of general formula: wherein: A1 and A2 are independently selected from the group consisting of mononuclear and polynuclear hydrocarbons; M1 is a metal from group IVb, Vb, or VIb of the Periodic Table; R1 and R2 are independently selected from the group consisting of hydrogen, C1-C10 alkyl, C1-C10-alkoxy, C6-C10 aryl, C6-C10 aryloxy, C2-C10 alkenyl, C7-C40 arylalkyl, C7-C40 alkylaryl, C8-C40 arylalkenyl and halogen; R7 is selected from the group consisting of: ═BR11, ═AlR11, —Ge—, —Sn—, —O—, —S—, ═SO, ═SO2, ═NR11, ═CO, ═PR11 and &

Abstract: An olefin polymerization catalyst is described which includes: (A) a solid catalyst component being prepared by copulverizing a magnesium compound, an aluminum compound, an electron donor and a titanium compound, and (B) an organoaluminum compound. The present invention is also directed to a process for preparing polyolefins using the aforesaid catalyst system to polymerize olefins.

Abstract: A process for polymerizing propylene is disclosed. The propylene is polymerized with a catalyst system which comprises an activator and a [1,2-b]indenoindolyl Group 4-6 transition metal complex having open architecture. The process has high catalyst activity and gives high molecular weight elastomeric polypropylene.

Abstract: An ethylene-based polymer resin which is obtained by copolymerizing ethylene with an &agr;-olefin having 5 to 20 carbon atoms, and has a melt flow rate (MFR) measured at 190° C. under a load of 21.18N according to JIS K7210-1995, of not more than 0.01 g/10 min. and less than 1 g/10 min., wherein the melt flow rate and a melt tension (MT) at 190° C.

Abstract: The present invention relates to a process for the gas-phase (co-)polymerisation of olefins in a fluidised bed reactor using a chromium oxide catalyst characterised in that the polymerisation is performed in the presence of a polymer structure modifier.

Abstract: Irradiated, oxidized olefin polymer dispersing aids for use in the manufacture of additive concentrates and additive-containing olefin polymer compositions.

Abstract: The invention relates to a method for producing ethylene homo- and copolymers in a tubular reactor at pressures above 1000 bar and temperatures in the range from 120 to 350° C. by free-radical polymerization, in which firstly small amounts of free-radical chain initiators are added to a mobile flow medium comprising ethylene, molecular weight regulator and optionally polyethylene, and the polymerization is then carried out.

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, trialkylsiloxyalutninum, and a combination of trialkylboron and thalkylaluminum 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: An ethylene-&agr;-olefin copolymer obtained by a gas phase polymerization method in the presence of a catalyst, wherein the copolymer satisfies the following conditions (A-1) to (A-4): (A-1) Melt flow rate (MFR): 0.3 to 5.0 g/10 minutes (A-2) Melt flow rate ratio (MFRR): 20 or more (A-3) Density (d): 0.910 to 0.930 g/cm3 (A-4) Coldxylene-soluble portion (CXS)(wt %) is in the range defined by the formula (1): 1.5×10−4×d−125×MFR0.5+0.3≧CXS  formula (1).

Abstract: An ethylene polymerization process is disclosed. The process uses a single-site catalyst that contains a boraaryl ligand. It comprises supporting the catalyst, forming a slurry of the supported catalyst in an organic solvent, mixing the catalyst slurry with trialkyl aluminum compound, and polymerizing ethylene in the presence of the trialkyl aluminum-treated catalyst slurry. The process gives polyethylene having a controlled long-chain-branch index.

Abstract: Ethylene copolymers are prepared with comonomers selected from: (a) &agr;-olefins, (b) cycloolefins and (c) polyenes, with a content of ethylene units of between 80 and 99 mol %, a content of units derived from &agr;-olefin, cycloolefin and/or polyene comonomers of between 1 and 20 mol %, characterized in that: (a) in TREF (Temperature Rising Elution Fractionation) analysis, a quantity equal to at least 90% by weight of the copolymer is eluted within a temperature interval of less than 50° C., and (b) Mw/Mn>3, where Mw is the weight-average molecular weight and Mn is the number-average molecular weight, both determined by means of GPC.

Abstract: A polymer includes at least propylene as a first monomeric component, 1-pentene as a second monomeric component, and, as a third monomeric component, a third olefin. The third olefin has fewer than 5 carbon atoms, is linear and is not propylene, or has 5 carbon atoms and is branched, or has more than 5 carbon atoms and is linear or branched.

Abstract: The present invention discloses a process for the polymerization of olefins in the presence of a catalyst comprising metal complexes of 2,6-diacetylpyridine bis-imines Preferably, the metal is a trivalent metal is selected from the group consisting of trivalent Fe, Ru, or Cr.

Abstract: A catalyst composition for preparing olefin polymers. The catalyst composition includes a metallocene compound and an activating cocatalyst. In the metallocene compound, two cyclopentadienyl groups are bridged by X (carbon, silicon, germanium or tin) in a ring structure. The bite angle &thgr; formed by the two cyclopentadienyl rings and X is equal to or greater than 100 degrees. The obtained olefin polymer has high cycloolefin conversion and a high glass transition temperature. In addition, the catalyst composition can still maintain relatively high activity at high temperature reaction conditions.

Abstract: A catalyst composition includes: A) a solid catalyst precursor containing a metallocene compound, a magnesium compound and a particulate polymeric material; and B) a cocatalyst containing aluminum compound. The catalyst is prepared by combining metallocene compound, magnesium compound and particles of polymeric material to form a catalyst precursor; and activating the catalyst precursor with alkylaluminums and/or aluminoxanes. Homopolymeric or copolymeric polyolefins are produced by contacting olefins or olefins and alpha-olefins with the catalyst composition.

Abstract: A continuous vapor-phase fluidized-bed process for the preparation of ethylene homopolymers and copolymers having a density of from 0.87 to 0.97 g/cm3 in which ethylene or mixtures of ethylene and C3-C8 a-monoolefins are (co)polymerized in the presence of a supported chromium catalyst in the polymerization zone of a vapor-phase fluidized-bed reactor under pressures ranging from 1 to 100 bar and at temperatures ranging from 30° to 125° C.

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 multi-functional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ethers for controlled polymerization.

Abstract: A catalyst composition for preparing olefin polymers. The catalyst composition includes a metallocene compound and an activating cocatalyst. In the metallocene compound, two cyclopentadienyl groups are bridged by X (carbon, silicon, germanium or tin) in a ring structure. The bite angle 0 formed by the two cyclopentadienyl rings and X is equal to or greater than 100 degrees. The obtained olefin polymer has high cycloolefin conversion and a high glass transition temperature. In addition, the catalyst composition can still maintain relatively high activity at high temperature reaction conditions.

Abstract: A process for the continuous gas-phase (co-)polymerisation of olefins in a fluidised bed reactor using a Ziegler-Nata type catalyst wherein the polymerisation is performed in the presence of a process aid additive selected from at least one of (1) a polysulphone copolymer; (2) a polymeric polyamine or (3) an oil-soluble sulphonic acid.

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: A process for the polymerization of olefins is disclosed. A boraaryl catalyst precursor and an activator are used in the presence of a silane modifier. A low level of silane modifier enhances the activity of the catalyst.

Abstract: The present invention concerns a process for producing homogeneous polyethylene compositions and processes for making high density, medium density and low density films therefrom. The process comprises carrying out the polymerization in the presence of an ethylene-polymerizing catalyst system in a multistage reaction sequence of successive polymerization stages, at least one of which is a loop polymerization stage, and at least one of which is a gas phase polymerization stage. According to the invention, said loop polymerization stage is operated using a diluent selected from the group of linear and branched C4-C6 hydrocarbons and/or mixtures thereof. The reactor sequence is operated with different amounts of hydrogen and comonomers to produce a high molecular weight portion in one of the polymerization stages and a low molecular weight portion in another, so as to provide bimodal polyethylene composition with a low molecular weight part having an MFR2 of 250 g/10 min or more.

Abstract: A process for preparing an ethylene/&agr;-olefin copolymer, which includes the steps of (A) copolymerizing ethylene and an &agr;-olefin of 3 to 20 carbon atoms by continuous vapor phase polymerization; (B) copolymerization is conducted in the presence of a prepolymerized catalyst obtained by prepolymerizing an olefin in the presence of (a) a transition metal compound, (b) an organoaluminum oxy-compound, (c) a fine particle carrier, and optionally (d) an organoaluminum compound; and (C) copolymerization is conducted under such condition that the partial pressure of sum total of ethylene and &agr;-olefin is 10 to 28 kg/cm2. The resulting ethylene/&agr;-olefin copolymer has the following properties: (i) the density is in the range of 0.880 to 0.960 g/cm3, (ii) the melt flow rate of 190° C. under a load of 2.16 kg is in the range of 0.1 to 100 g/10 min, (iii) the melt tension (MT (g)) at 190° C. and the melt flow rate (MFR (g/10 min)) satisfy the relation MT≦2.2×MFR−084.

Abstract: A process for the gas-phase (co-)polymerization of olefins in a fluidized bed reactor using a chromium oxide catalyst. The polymerization is performed in the presence of a process aid additive.

Abstract: Methods and compositions for inhibiting the polymerization of vinyl monomers are disclosed. Combinations of aminophenol compounds and nitroxyl radical compounds are effective at inhibiting vinyl monomer polymerization under both processing and storage conditions.

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 liner ethylene polymers. T 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: Films with excellent machine direction (MD) tear properties comprise at least one layer made from a polymer comprising:

Abstract: The present invention relates to a semiconductor device using a copolymer-containing photoresist, and a process for manufacturing the same. As a norbornene derivative (monomer) having a hydrophilic group is synthesized and introduced to the backbone chain of a polymer, the polymer according to the present invention has excellent etching resistance and heat resistance, which are the characteristic points of alicyclic olefin structure, and provide excellent resolution due to prominent enhancement of adhesiveness resulted from introducing a hydrophilic group (—OH).

Abstract: Ths invention provides a process for the preparation of a polyethylene, in particular an HDPE suitable for blow moulding of HIC, which comprises polymerizing ethylene and, optionally an ethylenically unsaturated comonomer copolymerizable therewith, in the presence of a catalyst comprising a first silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 350 m2/g and a chromium content of 0.1 to 1.0% by weight and a second silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 450 m2/g and a chromium content of 0.1 to 1.0% by weight, wherein the silica support of said first catalyst also comprises alumina and the silica support of said second catalyst also comprises titanium, and preferably a co-catalyst.

Abstract: Multimodal polyolefin polymers may be prepared in series-connected polymerization reactors where a prior reactor is a slurry reactor employing light solvent as the slurry medium and hydrogen to limit polymer molecular weight, the polymer product from the prior reactor being substantially freed of hydrogen prior to entry into a subsequent polymerization reactor operating at low hydrogen pressure to produce a high molecular weight olefin. The economics and operating performance of such a series slurry reactor polyethylene process can be significantly improved through the use of an intermediate slurry transfer system and hydrogen removal apparatus that employs flash drums in series in conjunction with a warm recycle solvent slurry diluent.

Abstract: A process for preparing a butyl polymer, the process comprising contacting a C4 to C8 monoolefin monomer with a C4 to C14 multiolefin monomer at a temperature in the range of from about −100° C. to about +50° C. in the presence of a diluent and a catalyst mixture comprising a monoalkylaluminum dihalide and an aluminoxane.

Abstract: A process for producing a polyolefin according to the present invention comprises (co) polymerizing one or two or more &agr;-olefins in a vapor phase in a fluidized-bed reactor, wherein the concentration of (A) a saturated aliphatic hydrocarbon in the fluidized bed reactor is 1 mol % or more and at least one compound selected from (B) an aliphatic amide and (C) a nonionic surfactant constituted only of carbon, oxygen and hydrogen atoms is made to exist in the reactor. The present invention can provide a process for producing a polyolefin, the process ensuring that the prevention of clogging caused by the generation of sheet or block polymers and a high efficiency of the production of a polyolefin due to good catalytic activity can be accomplished at the same time and also having superb continuous productivity.

Abstract: Non-tacky, base polymers are plasticized into pressure-sensitive adhesives and comprise: a) about 100 parts by weight of a base copolymer having a Tg greater than about 0° C., wherein the base copolymer is formed from and comprises: (1) about 50 to 70% by weight of a high Tg comonomer component, wherein the homopolymer formed from the high Tg comonomer component has a Tg of at least about 20° C.; (2) optionally, up to about 20% by weight based on the total weight of the base copolymer of an acidic comonomer; and (3) about 30 to 50% by weight of one or more low Tg (meth)acrylate comonomer, wherein the Tg homopolymer of the low Tg comonomer is less than about 20° C., and b) about 1 to about 100 parts based on the base copolymer of a nonreactive, non-volatile, non-acrylic-based plasticizing agent.

Abstract: The invention discloses ruthenium alkylidene complexes of the type (PCy3)(L)Cl2Ru(CHPh), where L is a triazolylidene ligand of the general formula: These catalysts have been found to be considerably more active for olefin metathesis at elevated temperatures than the parent catalyst (PCy3)2Cl2Ru(CHPh)(2). For example, complex 14 (L=1,3,4-triphenyl-4.5-dihydro-1H-triazol-5-ylidene) is able to catalyze the ring-closing metathesis of substituted dienes to give tetra-substituted cyclic olefins in good yield. In addition, this complex demonstrates the analogous stability towards oxygen and moisture exhibited by ruthenium alkylidene 2.

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 with the proviso that an arbitrary or rather regular sequence of isotactic and atactic blocks is excluded, the polymer having a mean molecular weight Mw within the range of from 100,000 to 800.000 gms/mol and a TG of from −50 to +30.

Abstract: The vulcanizates produced using the rubber mixtures according to the invention, in which the vulcanizates contain agglomerated rubber gels, are distinguished by improved mechanical properties with an at least equivalent damping behavior.

Abstract: This invention provides catalyst compositions that are useful for polymerizing at least one monomer to produce a polymer. This invention also provides catalyst compositions that are useful for polymerizing at least one monomer to produce a polymer, wherein said catalyst composition comprises a post-contacted organometal compound, a post-contacted organoaluminum compound, and a post-contacted treated solid oxide compound.

Abstract: A single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an inorganic compound comprising iron and a tridentate N-(2-ethylamino)-2-pyridylmethanimino or N,N-bis(2-pyridylmethyl)amino ligand. The late transition metal catalyst is active in olefin polymerization.

Abstract: The present invention relates to a process for the copolymerisation of conjugated diolefins with non-conjugated olefins in the presence of rare earth metal catalysts. The advantages of the process according to the invention are in particular the high selectivity, good space-time yield and the possibility of being able to vary the reaction conditions within a wide range.

Abstract: In a process for preparing ethylene-vinyl acetate copolymers in which a mixture of ethylene and vinyl acetate is polymerized continuously in the presence of free-radical polymerization initiators and, if desired, molecular weight regulators in a cooled tube reactor at a pressure in the range from 1000 to 3500 bar, and the poly-merization initiator is added at the beginning and at two or more points along the tube reactor, and temperature changes in the reaction mixture along the tube reactor, between the first temperature maximum and the last addition of the polymerization initiator, are within a range of not more than 20° C.

Abstract: The present invention is directed to a method of forming a polymer composition having quaternary alkane units and aromatic hydrocarbon units. The aromatic hydrocarbon units have substituents of the general formula R1SiR2R3R4, wherein R1 is optional and is a hydrocarbon or ether linking the silicon and the aromatic hydrocarbon, and R2, R3, and R4 are one or more of hydrogen, alkyl, and alkoxy, with the provision that no more than two may be hydrogen or alkyl.

Abstract: A process for polymerizing monomers in the gas phase, in fluidized bed reactors is described, where unsaturated, gas phase monomers are fed into the reactors in the presence of a mixture of inert diluents having a composition that allows the dew point to be adjusted, this leading to high production rates under stable operation in a non condensed operation mode.

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

Abstract: Low color, aromatic modified C5 hydrocarbon resins are disclosed. The resins are predominantly an aromatic modified piperylene resin. The resins are useful as tackifiers in hot melt adhesives and hot melt pressure sensitive adhesives.

Abstract: A catalyst composition for preparing olefin polymers. The catalyst composition includes a metallocene compound and an activating cocatalyst. In the metallocene compound, two cyclopentadienyl groups are bridged by X (carbon, silicon, germanium or tin) in a ring structure. The bite angle &thgr; formed by the two cyclopentadienyl rings and X is equal to or greater than 100 degrees. The obtained olefin polymer has high cycloolefin conversion and a high glass transition temperature. In addition, the catalyst composition can still maintain relatively high activity at high temperature reaction conditions.

Abstract: A drag-reducing polymer capable of dissolving even in cold fluids is described, along with a method for manufacturing said drag-reducing polymer. The drag-reducing polymer has at least one alpha-olefin monomer with between a four and nine carbon chain length and a co-monomer and has less than 25% monomers (molar content) with carbon chain lengths of 12 or longer. A drag-reducing polymer suspension is also described.

Abstract: “Cast” films having excellent puncture resistance and tear strength are manufactured from “pseudohomogeneous” linear low-density polyethylene resin. The preferred pseudohomogeneous resins used in the present invention are prepared with an advanced Ziegler Natta catalyst (having a magnesium component and a titanium component), preferably in medium pressure solution polymerization process. The films of this invention are especially suitable for “pallet wrapping” and for wrapping goods of unusual or uneven shapes and sizes.