Abstract: The object of the present invention is to provide a production method of a high molecular weight aromatic polycarbonate containing a reduced amount of a high melting point product, and having less thermal history received and excellent hue by a melt process. The present invention relates to a production method of an aromatic polycarbonate, characterized in that in producing an aromatic polycarbonate using an aromatic dihydroxy compound and a carbonic diester as raw materials and using plural reactors, a molten reactant temperature T1 (° C.) in at least one reactor A and a molten reactant temperature T2 (° C.) in a reactor B subsequent to the reactor A are satisfied with the relationship of T2<T1, and an evaporation surface area per unit treatment amount of a molten reactant in the reactor to which a molten reactant having a limiting viscosity of 0.1 dl/g or more is supplied is 1.0 m2·hr/m3 or more.

Abstract: The present invention discloses the use of a chromium-based catalyst system in two serially connected loop reactors for copolymerising ethylene and a comonomer, at reduced productivity, the final polyethylene having a reduced amount of gel.

Abstract: A process for making an ethylene homopolymer in the presence of an oxide-supported chromium catalyst is disclosed. A small amount of an ?-olefin contacted with the catalyst before polymerizing ethylene or introduced into an ethylene homopolymerization unexpectedly boosts process productivity. When used at part per million levels, the ?-olefin improves productivity while maintaining desirable polymer properties. The invention is particularly valuable for making HDPE resins useful for blow molding applications.

Abstract: Catalyst for the polymerization and/or copolymerization of olefins which is obtainable by application to a finely divided inorganic support and concluding calcination at temperatures of from 350 to 1050° C. and has a chromium content of from 0.1 to 5% by weight and a zirconium content of from 0.5 to 10% by weight, in each case based on the element in the finished catalyst, with the molar ratio of zirconium to chromium being from 0.6 to 5.

Abstract: Process for preparing a supported catalyst for the polymerization and/or copolymerization of olefins which has a chromium content of from 0.01 to 5% by weight, based on the element, which comprises (a) preparing a homogeneous solution comprising an organic or inorganic chromium compound and at least one further organic or inorganic compound of elements selected from among Mg, Ca, Sr, B, Al, Si, P, Bi, Sc, V, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Rh, Pd, Hf, Ta, W in a protic or aprotic polar solvent, (b) bringing the solution from a) into contact with a finely divided inorganic support to form a catalyst precursor, (c) if appropriate, removing the solvent from the catalyst precursor and (d) calcining the catalyst precursor at temperatures of from 350 to 950° C., preferably 400 to 900° C., under oxidative conditions.

Abstract: The present invention relates to the removal of hydrocarbon residues from a catalyst and more specifically the air activation of a catalyst containing hydrocarbon residues. It also relates to extruded pipe and utility conduit resins comprising polyethylene, household/industrial chemicals container resins, and to a polyethylene resin particularly suitable for large parts by blow molding and sheet extrusion procedures, wherein the resin is made by a process using an activated chromium and titanium-based catalyst.

Abstract: The invention relates to a process for preparing a poly-1-olefin by polymerization of a 1-olefin of the formula R4CH?CH2, where R4 is hydrogen or an alkyl radical having from 1 to 10 carbon atoms, in suspension, in solution or in the gas phase, at a temperature of from 20 to 200° C. and a pressure of from 0.

Abstract: The present invention is directed to the use of aluminum alkyl activators and co-catalysts to improve the performance of chromium-based catalysts. The aluminum alkyls allow for the variable control of polymer molecular weight, control of side branching while possessing desirable productivities, and may be applied to the catalyst directly or separately to the reactor. Adding the alkyl aluminum compound directly to the reactor (in-situ) eliminates induction times.

Abstract: Methods of making supported chromium catalyst systems and processes of polymerizing ethylene using the supported chromium catalyst systems are disclosed. A method of forming a catalyst system in a polymerization reactor includes contacting a supported chromium catalyst and a metal alkyl cocatalyst by cofeeding the catalyst and cocatalyst to the reactor or feeding the catalyst and cocatalyst separately to the reactor, to form a catalyst system. The catalyst and cocatalyst are not pre-contacted prior to the feeding or cofeeding step. The catalyst system can be contacted with ethylene and optional alpha-olefin comonomer to form polyethylene.

Abstract: The invention relates to a process for preparing an essentially spherical support for olefin polymerization catalysts, which comprises the steps: preparation of a hydrogel comprising a cogel of silicon oxide and at least one further metal oxide, if appropriate, washing of the hydrogel until the content of alkali metal ions is less than 0.1% by weight, based on the weight of solids, extraction of the water from the hydrogel until the water content is less than 5% by weight, based on the total content of liquid, and drying of the hydrogel to form a xerogel. According to the invention, the extraction step comprises at least one first extraction with a first organic solvent which is at least partially miscible with water down to a water content of 50% by weight, followed by at least one second extraction with a second organic solvent which is at least partially miscible with water.

Abstract: A process for the preparation of a chromium-type supported olefin polymerization catalyst. A fluidized bed of support particles in an inert carrier gas is established. A chromium (III) compound is added to the fluidized support particles to provide a supported catalyst component. The supported catalyst component is activated to convert at least a portion of the chromium (III) to Chromium (VI). The chromium (III) containing particles may be recovered from the fluidized bed and then activated or they may be activated in the fluidized bed. Also the support particles can be treated in the fluidized bed with other treatment agents. The support particles may be pretreated with a solution of a boron treating agent prior to incorporation of the support in the fluidized bed.

Abstract: The present invention is directed to the use of aluminum alkyl activators and co-catalysts to improve the performance of chromium-based catalysts. The aluminum alkyls allow for the variable control of polymer molecular weight, control of side branching while possessing desirable productivities, and may be applied to the catalyst directly or separately to the reactor. Adding the alkyl aluminum compound directly to the reactor (in-situ) eliminates induction times.

Abstract: The present invention is directed to the use of aluminum alkyl activators and co-catalysts to improve the performance of chromium-based catalysts. The aluminum alkyls allow for the variable control of polymer molecular weight, control of side branching while possessing desirable productivities, and may be applied to the catalyst directly or separately to the reactor. Adding the alkyl aluminum compound directly to the reactor (in-situ) eliminates induction times.

Abstract: This invention is directed to processes of making polymer in the presence of a hydrofluorocarbon or perfluorocarbon and recovering the polymer. The processes provided enable polymerization processes to be practiced with minimal fouling in the reaction system, and provide polymer products that can be manufactured to relatively low densities. The invention is particularly beneficial in the production of ethylene based polymers using chromium catalyst systems.

Abstract: Plastics pipes comprise polyolefins which can be prepared by means of a fluorine-modified chromium catalyst and are used for transporting gases and liquids.

Abstract: The invention relates to a process for preparing a poly-1-olefin by polymerization of a 1-olefin of the formula R4CH?CH2, where R4 is hydrogen or an alkyl radical having from 1 to 10 carbon atoms, in suspension, in solution or in the gas phase, at a temperature of from 20 to 200° C. and a pressure of from 0.

Abstract: An olefin polymerisation process carried out in the presence of an anti-fouling agent and a chromium-type catalyst or Ziegler Natta catalyst; characterised in that the anti-fouling agent comprises an anti-fouling polymer having an average molecular weight (Mw) of greater than 1000 daltons and containing: (1) one or more blocks —(CH2—CH2—O)k— where each k is in the range from 1 to 50; and (2) one or more blocks —(CH2—CH(R)—(O)n? where R comprises an alkyl group having from 1 to 6 carbon atoms and each n is in the range from 1 to 50, and terminated by a R? and a R? end groups, wherein R? is OH or an alkoxy having from 1 to 6 carbon atoms and R? is H or an alkyl having from 1 to 6 carbon atoms.

Abstract: The invention relates to a polymer of ethylene which has a ?o/?2 ratio of at least 13; and a high load melt index HLMI lower than 8 g /10 min, and a value of tan ? at ?/?c=0.01 of less than 1.3, where ? is G?/G?, ? is the frequency at which G? and G? are measured and we is the frequency at which G?=G?, and G and G? are respectively the elastic modulus and viscous modulus, both measured in Pa at 190° C.; a process for making the polymer using a catalyst comprising chromium supported on a silica-titania support is also described.

Abstract: Catalyst for the polymerization and/or copolymerization of olefins which is obtainable by application to a finely divided inorganic support and concluding calcination at temperatures of from 350 to 1050° C. and has a chromium content of from 0.1 to 5% by weight and a zirconium content of from 0.5 to 10% by weight, in each case based on the element in the finished catalyst, with the molar ratio of zirconium to chromium being from 0.6 to 5.

Abstract: Novel supported, titanized chromium catalysts for the homopolymerization of ethylene and the copolymerization of ethylene with ?-olefins, a process for preparing them and to their use for the polymerization of olefins.

Abstract: A method for producing an ethylene polymer which comprises continuously polymerizing ethylene alone or copolymerizing ethylene and a C3-C8 ?-olefin by multistage polymerization in a plurality of polymerization reactors connected in series in the presence of a chromium catalyst having at least a part of chromium atoms converted to hexavalent chromium carried on an inorganic oxide carrier by calcination-activating in a non-reducing atmosphere, wherein an organoaluminum compound of the formula (1): (R1)xAl(OR2)y(OSiR3R4R5)z??(1) (in the above formula, R1 and R2 may be the same or different, each represents a C1-C18 alkyl group or a C6-C18 aryl group, R3, R4 and R5 may be the same or different, each represents a C1-C18 alkyl group or a C6-C18 aryl group, R1, OR2 and OSiR3R4R5 respectively may be the same or different when each has a plurality of kinds, and x, y and z are respectively 0?x?3, 0?y<3, 0?z<3, and x+y+z=3) is introduced at least one or all of the polymerization reactors.

Abstract: A method for polymerizing ethylene is provided. The method can include preparing a supported catalyst composition comprising the steps of: (a) dehydrating a chromium impregnated support; (b) at least partially dissolving a titanium-containing compound in one or more inert solvents to provide a solution comprising the titanium-containing compound; (c) contacting the dehydrated chromium impregnated support with the titanium-containing solution to provide a mixture comprising the solvent, titanium-containing compound and chromium impregnated support; (d) removing the solvent from the mixture; and (e) activating the product of step (d) at a temperature of at least 800° F. (427° C.) to provide a supported titanated chrome catalyst composition. The supported titanated chrome catalyst composition can be feed to a slurry reactor, and contacted with an optional co-catalyst, under polymerization conditions, with ethylene.

Abstract: Disclosed are a copolymer of a perfluoropolyether derivative and a photosensitive polymer, a composition for forming banks comprising the copolymer, and a method for forming banks using the composition. Also disclosed is an organic thin film transistor including the composition and an electronic device including the organic thin film transistor. The use of the copolymer may enable the formation of banks by a solution coating process. Because an organic thin film transistor including banks formed by the method may be fabricated without any degradation in the characteristics of the organic thin film transistor, improved electronic properties may be exhibited.

Abstract: Novel supported, titanized chromium catalysts for the homopolymerization of ethylene and the copolymerization of ethylene with ?-olefins, a process for preparing them and to their use for the polymerization of olefins.

Abstract: Broad molecular weight polyethylene and polyethylene having a bimodal molecular weight profile can be produced with chromium oxide based catalyst systems employing alkyl silanols. The systems may also contain various organoaluminum compounds. Catalyst activity and molecular weight of the resulting polyethylene may also be tuned using the present invention.

Abstract: Methods of polymerizing at least one olefin include contacting the olefin with a catalyst comprising chromium and with a cocatalyst comprising a non-transition metal cyclopentadienyl (Cp) compound. The polymerization may be performed in the presence of hydrogen. Using the cocatalyst in conjunction with the catalyst increases several properties, such as the high load melt index (HLMI), the MW, and the MN, of the polymers produced by this polymerization method. Polymer compositions produced by such methods have various unique properties, including a PDI greater than about 30. Additional embodiments include articles of manufacture or end use articles formed from such polymer compositions.

Abstract: This invention relates to a catalyst system comprising a catalyst and a support comprising a non-layered inorganic porous crystalline phase material, wherein the support comprises a hexagonal arrangement of uniformly-sized pores having an average pore diameter greater than or equal to about 13 ?, an X-ray diffraction pattern having a calculated d100 value of greater than or equal to about 18 ?, an adsorption capacity of greater than or equal to about 15 grams benzene per 100 grams support at 50 torr and at 25° C., and a pore wall thickness of less then or equal to about 25 ?.

Abstract: This invention relates to a process of polymerizing ethylene in a reactor comprising contacting a catalyst system comprising a supported chromium catalyst and an aluminum alkyl cocatalyst, where the catalyst and cocatalyst are contacted by cofeeding the catalyst and cocatalyst to the reactor or feeding the catalyst and cocatalyst separately to the reactor, where the catalyst and cocatalyst are not contacted prior to the step of feeding or cofeeding, with ethylene, and from 0 to 50 mole % of one or more comonomers, where the polymerization occurs at a temperature between 50 and 120° C., and the molar ratio of aluminum from the cocatalyst to the chromium in the supported chromium catalyst is 30:1 or more.

Abstract: Methods of preparing a polymerization catalyst are provided that include contacting a support comprising alumina with a sulfating agent and with chromium. In an embodiment in which the chromium is provided from a chromium compound such as chromium oxide, the support may be calcined after loading the sulfating agent and the chromium on the support. Alternatively, the sulfating agent can be loaded on the support while calcining it. In another embodiment in which the chromium is provided from an organochromium compound, the support may be calcined after contacting it with the sulfating agent and before contacting it with the organochromium compound. Catalysts compositions formed by the foregoing method are provided. In an embodiment, catalyst compositions comprise chromium and a sulfate treated alumina support. The catalyst compositions have an activity for ethylene polymerization that is at least about 25% greater than an activity of the same catalyst without sulfate.

Abstract: This invention relates to a catalyst system comprising a catalyst and a support comprising a non-layered inorganic porous crystalline phase material, wherein the support comprises a hexagonal arrangement of uniformly-sized pores having an average pore diameter greater than or equal to about 13 ?, an X-ray diffraction pattern having a calculated d100 value of greater than or equal to about 18 ?, an adsorption capacity of greater than or equal to about 15 grams benzene per 100 grams support at 50 torr and at 25° C., and a pore wall thickness of less then or equal to about 25 ?.

Abstract: Methods of producing a polymer include contacting at least one olefin with a catalyst prepared by contacting a support comprising alumina with a sulfating agent and with chromium. Polymer compositions produced in this manner may exhibit relatively low levels of long chain branching and relatively high molecular weights. In an embodiment, polymer compositions with a PDI in a range of from about 6 to about 15 have MW values greater than about 300,000 g/mol and Eo values less than about 1×106 Pa·s. The polymer compositions may further have Theological breadths greater than about 0.25 and relaxation times less than about 10 seconds.

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

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

Abstract: Novel supported, titanized chromium catalysts can be used for the homopolymerization of ethylene and the copolymerization of ethylene with ?-olefins.

Abstract: A hollow plastic article is described, with at least one opening and with a structure which has one or more layers, the hollow plastic article comprising at least one layer made from a polyolefin which was prepared using a fluorine-modified chromium catalyst. The use of hollow plastic articles of the invention as plastic fuel containers, gasoline canisters, plastic tanks, or plastic bottles or the like is also described.

Abstract: Polyethylene resins having improved environmental stress crack resistance, stiffness and impact resistance is made by a process comprising feeding both a chromium oxide catalyst and a silyl chromium catalyst into a polymerization reactor. The chromium oxide catalyst and the silyl chromium catalyst are on separate supports. The chromium oxide catalyst is 25–50 weight percent and the silyl chromium catalyst is 50–75 weight percent of the total weight of catalyst. The catalysts may be added separately or as a single mixture.

Abstract: The invention provides a supported chromium catalyst system comprising a chromium catalyst precursor bound via at least one heteroatom to a functionalised support, said heteroatom being connected to said support via an organic group.

Abstract: Polymerization processes are disclosed for producing polyethylene having a target density and improved environmental stress resistance. Ethylene and optionally one or more ?-olefin comonomers, supported chromium catalyst, and metal alkyl cocatalyst are contacted to produce polyethylene. The density of the polyethylene is determined, and the concentration of cocatalyst is adjusted in response to a deviation between the density of the polyethylene and the target density. The catalyst and cocatalyst can be fed separately into the reactor, or can be co-fed, eliminating the need to pre-contact the catalyst and cocatalyst prior to introducing them into the reactor.

Abstract: The invention relates to a process for preparing a catalyst for the polymerization of olefins, which comprises: a) preparation of a finely divided silica xerogel, b) loading of the xerogel with chromium from a solution of chromium trioxide or a chromium compound which is converted into chromium trioxide under the conditions of step c), and c) activation of the resulting product at from 400 to 1100° C. in a water-free gas stream comprising oxygen in a concentration of above 10% by volume, wherein a fluoride doping with a fluorinating agent is carried out in step b) or in step c). Furthermore, the invention relates to a catalyst for the polymerization of olefins which is obtainable by the process of the invention and to a process for the polymerization of olefins in which an olefin or an olefin mixture is polymerized in the presence of a catalyst according to the invention.

Abstract: A process for preparing and controlling the density of high density polyethylene in the gas phase comprising contacting ethylene or a mixture of ethylene and one or more alpha-olefins with a chromium oxide catalyst supported on a granular or microspherical refractory oxide in a fluidized bed reactor in the presence of oxygen.

Abstract: A process to produce ethylene polymers is provided. Particularly, a process to produce ethylene polymers having a broad molecular weight distribution is provided. More particularly, a process to produce ethylene polymers that have low formation of smoke and odor during blow molding is provided.

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. in the vapor phase in an agitated bed of bulk material comprising particulate polymer, the resultant heat of polymerization is removed by cooling the recirculated reactor gas and the resulting (co)polymer is removed from the vapor-phase fluidized-bed reactor, wherein, for the preparation of a (co)polymer of a specific density d, the (co)polymerization is carried out at a temperature which is in a range restricted by an upper envelope defined by equation I T H = 171 + 6 ? ? ? d ? 0.

Abstract: A method of transitioning catalysts for polyolefin polymerization is provided. In one aspect, the process includes providing a polymerization reactor that includes a first catalyst system, contacting olefin monomers with the first catalyst system to form polyolefin in a first polymerization reaction and introducing a catalyst killer to the polymerization reactor in an amount sufficient to terminate the first polymerization reaction. The method further includes introducing a second catalyst system to the polymerization reactor in the presence of at least a portion of the catalyst killer, wherein the at least a portion of the catalyst killer is an amount sufficient to activate the second catalyst system and contacting olefin monomers with the second catalyst system to form polyolefin in a second polymerization reaction.

Abstract: Polymerization processes for ethylene and at least one mono-1-olefin comonomer having from about three to eight carbon atoms per molecule in the presence of a twice-aged catalyst system comprising chromium supported on a silica-titania support and a trialkylboron compound is provided. Novel ethylene copolymers also are produced.

Abstract: A polymerization catalyst is disclosed, wherein the catalyst comprises: (a) a metallocene of Ti, Zr or Hf, (b) an organoaluminum compound, and (c) a treated solid oxide support which comprises fluorine and chromium.

Abstract: A copolymer of ethylene and a higher alpha-olefin having broadened melt processing windows and reduced melt fracture can be produced using a chromium-containing catalyst system and a trialkyl boron cocatalyst. The polymerization process must be carefully controlled to produce a copolymer resin that easily can be made into articles of manufacture.

Abstract: A novel magnesium treated silica-containing compound that is useful as a support for chromium based olefin polymerization catalyst systems is provided which produces ethylene polymers having with MWD's that promote good properties particularly in HMW film applications.

Abstract: In a process for producing Phillips catalysts in which an oxidic support material is treated in suspension with a chromium salt solution and subsequently, after removing the solvent, calcined in an oxygen-containing atmosphere at above 300° C., the oxidic support material and/or the catalyst after calcination are/is, according to the present invention, comminuted until a mean particle size of <100 &mgr;m has been reached and the proportion of particles having a size of <50 &mgr;m is at least 30%, preferably in the range from 40 to 80%. A process for preparing homopolymers or copolymers of ethene in a loop reactor at from 30 to 150° C. under a pressure in the range from 0.2 to 15 MPa in the presence of a catalyst produced by the process of the present invention is also provided.

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: The invention relates to a process for preparing a catalyst for the polymerization of olefins, which comprises: a) preparation of a finely divided silica xerogel, b) loading of the xerogel with chromium from a solution of chromium trioxide or a chromium compound which is converted into chromium trioxide under the conditions of step c), and c) activation of the resulting product at from 400 to 1100° C. in a water-free gas stream comprising oxygen in a concentration of above 10% by volume, wherein a fluoride doping with a fluorinating agent is carried out in step b) or in step c). Furthermore, the invention relates to a catalyst for the polymerization of olefins which is obtainable by the process of the invention and to a process for the polymerization of olefins in which an olefin or an olefin mixture is polymerized in the presence of a catalyst according to the invention.