Abstract: An improved supported chromium oxide catalyst, a process for preparing the catalyst and a process for polymerizing olefin monomers utilizing the catalyst are provided. In accordance with the preparation process, chromium oxide and a support containing one or more of silica, titania, thoria, alumina, zirconia or aluminophosphates are combined, impregnated with a metal salt and activated. The metal salt is selected from the group consisting of alkali metal salts, alkaline earth metal salts and mixtures thereof.

Abstract: A copolymer of ethylene and a higher alpha-olefin, preferably 1-butene and/or 1-hexene, can be produced using an activated and subsequently carbon monoxide reduced chromium containing catalyst system and an alkylaluminum or alkylboron cocatalyst. The polymerization process must be carefully controlled to produce a copolymer resin that can be made into a tough product, with an increased melt index and a broad molecular weight distribution.

Abstract: High surface are aluminas are pre-calcined to form gamma-alumina. In one embodiment, the gamma-alumina is treated with an anhydrous solution of a fluorine-containing compound. In a second embodiment, alumina is precipitated in the pores of the gamma-alumina and then treated with a fluorine-containing compound. In a third embodiment a cogel of aluminum trifluoride and aluminum hydroxide is prepared. The three inventive fluorided alumina supports can be impregnated with a transition metal, preferably chromium, to form a catalyst system which can be used to polymerize mono-1-olefins.

Abstract: A copolymer of ethylene and a higher alpha-olefin, preferably 1-butane and/or 1-hexane, can be produced using an activated and subsequently carbon monoxide reduced chromium containing catalyst system and an alkylaluminum or alkylboron cocatalyst. The polymerization process must be carefully controlled to produce a copolymer resin that can be made into a tough product, with an increased melt index and a broad molecular weight distribution.

Abstract: A method for activating supported chromium oxide catalysts in which a chromium-containing catalyst on a silica-containing base is first heated in an oxidizing atmosphere at temperatures up to about 850.degree. C. and then cooled down. During the cooling step of the catalyst, the oxidizing atmosphere is replaced by a non oxidizing one, leading to an activated catalyst.A process for the polymerization of alpha-olefins, especially ethylene, in which at least one alpha-olefin is contacted, under polymerization conditions, with the catalyst activated by the method described above.

Abstract: Mixed catalyst compositions comprised of a first supported chromium-containing catalyst component and a second supported chromium-containing catalyst component and which additionally have one or more metallic or non-metallic catalytic agents associated therewith are provided. The additional metallic or non-metallic elements associated with the catalyst components can be aluminum, titanium, zirconium, boron, phosphorous or combinations thereof. The pore volume of the silica supports used for the first and second catalyst components differs by at least 0.3 cc/g. The mixed catalyst compositions of the invention are useful for the preparation of polyolefins. They are particularly useful of polymerization of ethylene in particle form polymerizations to produce high density polyethylene blow molding resins having good processability and physical properties. The improved particle form polymerization process and products obtained thereby using the above-described mixed catalyst compositions are also described.

Abstract: The present invention relates to a novel catalyst for the preparation of high molecular weight homopolymers and copolymers of ethene, which catalyst is obtainable by(1) loading a support based on silicon dioxide with(2) either chromium trioxide or a chromium compound capable of being converted to chromium trioxide under the conditions of stage (3) below and then(3) heating the resulting intermediate in a gas stream containing oxygen.the support (1) being a special silica xerogel obtained by extracting not more than 30% of the water from a silica hydrogel by means of an alkanol, an alkanone or a mixture thereof followed by drying, comminution and fractional screening.

Abstract: Olefins are polymerized with a catalyst composition which forms on mixing a supported chromium oxide catalyst system and a silane compound. This composition allows the production of one or more comonomers in-situ. The resultant polymer has a lower density, a higher melt index, and a higher high load melt index than polymers produced with a similar catalyst system in the absence of a silane compound.

Abstract: High surface aluminas are pre-calcined to form gamma-alumina. In one embodiment, the gamma-alumina is treated with an anhydrous solution of a fluorine-containing compound. In a second embodiment, alumina is precipitated in the pores of the gamma-alumina and then treated with a fluorine-containing compound. In a third embodiment a cogel of aluminum trifluoride and aluminum hydroxide is prepared. The three inventive fluorided alumina supports can be impregnated with a transition metal, preferably chromium, to form a catalyst system which can be used to polymerize mono-1-olefins.

Abstract: The present invention relates to a process for the polymerization of ethylene or copolymerization of ethylene and at least one other alpha-olefin, in the gas phase in a fluidized bed reactor, in the presence of a catalyst comprising chromium compounds associated with a granular support comprising a refractory oxide and activated by thermal treatment, which process is characterized in that the catalyst is used in the form of active particles of prepolymer, obtained by bringing the said catalyst in contact with ethylene, alone, or in a mixture with at least one higher alpha-olefin, in such a way that the prepolymer contains from 4.times.10.sup.-5 to 3 milligram atoms of chromium in the catalyst per gram.

Abstract: A supported catalyst for ethene polymerization by Phillips catalysis is disclosed. The supported catalyst is prepared by (1) mixing a porous silicate in an inert, organic liquid to produce a silicate suspension, (2) providing an ester of phosphoric acid or phosphorous acid, (3) mixing an organic liquid, a chromium compound, and a trialkylaluminum compound to produce a chromium compound/aluminum compound and combining the silicate suspension, the phosphorus compound and the chromium compound/aluminum compound suspension. This resulting suspension is evaporated to dryness to form a catalyst intermediate. The catalyst intermediate is heated in nitrogen, then heated in an oxygen-containing atmosphere, and then heated again in nitrogen to produce an activated catalyst. The activated catalyst is suspended in an organic liquid and treated with an alkyl boron compound to produce the desired supported catalyst.

Abstract: A process has been discovered for the polymerization of ethylene and mixtures of ethylene with at least one other mono-1-olefin by employing a polymerization catalyst that produces polymers containing terminal vinyl unsaturation wherein such catalyst is exposed to a modifying agent prior to or during the polymerization reaction.

Abstract: A silica-titania cogel or silica-titanic-chromium tergel is first aged at a substantially neutral pH, then aged at an alkaline pH, and then spray dried or azeotrope dried to form a xerogel. Optionally, a pore- preserving agent can be added prior to drying. The cogel can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Abstract: A copolymer of ethylene and a higher alpha-olefin, preferably 1-hexene and/or 4-methyl-1-pentene, can be produced using an activated and subsequently carbon monoxide reduced chromium containing catalyst and a trialkyl boran cocatalyst. The polymerization process must be carefully controlled to produce a copolymer resin that can be made into a tough, impact resistant film.

Abstract: There is described a process for the production of pigment/plastic premixes characterized by homogeneous distribution of pigment in a polymer matrix. The invention is based on the polymerization of olefins carried out by means of a process using Ziegler catalyst. Significantly the polymerization occurs on the surface of the pigment particles, after the prior activation of the pigment particles.

Abstract: A supported catalyst for polymerizing 1-olefins, for example, ethylene, is prepared by depositing a chromium compound and a titanium compound on a refractory oxide support which is substantially non-spherical, and which has a relatively broad particle size distribution range. The catalyst is preferably combined, either outside of the polymerization vessel or in situ, with a sufficient amount of at least one magnesium composition of the formula RMgR', where R and R' are the same or different and they are C.sub.1 to C.sub.12 hydrocarbyl groups, to provide a molar ratio of magnesium to chromium in the catalyst composition of about 0.01:1 to about 25:1. The resulting catalyst composition has good feedability and fluidization characteristics, and it produces resins of relatively high HLMI at relatively low temperatures.

Abstract: A method for activating supported chromium oxide catalysts in which a chromium-containing catalyst on a silica-containing base is first heated in an oxidizing atmosphere at temperatures up to about 850.degree. C. and then cooled down. During the cooling step of the catalyst, the oxidizing atmosphere is replaced by a non-oxidizing one, leading to an activated catalyst. A process for the polymerization of alpha-olefins, especially ethylene, in which at least one alpha-olefin is contacted, under polymerization conditions, with the catalyst activated by the method described above.

Abstract: A process for producing polyethylene is disclosed in which ethylene is polymerized in the presence of a composite catalyst. The catalyst is made up of a solid catalyst component typified by a selected chromium compound, a modified aluminum compound typified by a trialkylaluminum and an R.sub.n.sup.1 Al(OR.sup.2).sub.3-n compound wherein R.sup.1 and R.sup.2 are represented by selected hydrocarbon groups and n by 0.ltoreq.n.ltoreq.3. The polymer has improved melt index, flow parameter and melt tension characteristics.

Abstract: The present invention relates to a process for starting up the polymerization of ethylene or copolymerization of ethylene and at least one other alpha-olefin by bringing ethylene and optionally at least one other alpha-olefin in contact under fluidized-bed polymerization or copolymerization conditions and/or stirred mechanically, with a charge powder in the presence of a catalyst comprising a chromium oxide compound associated with a granular support and activated by thermal treatment, this catalyst being used in the form of a prepolymer, this process being characterized in that the charge powder employed is previously subjected to a treatment by contacting the said charge powder with an organo-aluminium compound, in such a way that the polymerization or copolymerization starts up immediately after the contacting of the ethylene and optionally one other alpha-olefin with the charge powder in the presence of the prepolymer.

Abstract: This invention relates to a high-temperature slurry polymerization of ethylene where: the hexene is generated in situ; a chromium catalyst system is used; a trialkyl boron or a polyalkyl silane compound is used as a cocatalyst; the temperature of the reaction is above the foul curve temperature for a specific copolymer density; and where the polymerization takes place in a continuous loop reactor which has isobutane as a diluent. Additionally, hexene can be withdrawn, or added, to adjust the density.

Abstract: A process for the continuous polymerization of one or more alpha-olefins with a transition metal catalyst, in a reactor having a fluidized and/or mechanically stirred bed, in which a very small amount of an activity retarder, generally less than 0.1 ppm, is introduced continuously into the reactor at a flow rate which is varied with time so as to keep substantially constant either the polymerization rate or the content of transition metal in the polymer produced. Suitable activity retarders include polymerization inhibitors such as, for example, oxygen, alcohols, carbon monoxide and carbon dioxide and electron donor compounds such as amides and ethers.

Abstract: In one embodiment of this invention a surface silicated alumina composition, as opposed to conventional silica alumina, is provided. Such composition may also be fluorided and/or phosphated or phosphited. The resulting compositions are broadly useful but are of particular applicability as supports for chromium olefin polymerization catalysts. In another aspect alumina is fluorided and used with hexavalent chromium catalyst and a co-catalyst or in the alternative with an organochromium catalyst. If desired the support in this embodiment can also be phosphated or phosphited. In another embodiment, aluminum phosphate is formed in the pores of alumina. In contrast with alumina catalyst supports of the prior art, the supports of this invention allow for the production of olefin polymers at high rates of productivity. Also novel high density ultrahigh molecular weight polymers are produced.

Abstract: An olefin, particularly alpha-olefin, polymerization catalyst composition, supported on a refractory oxide support comprises two chromium specie: (1) CrO.sub.3 or any chromium compound calcinable to CrO.sub.3 ; and (2) at least one silylchromate compound. The composition is prepared by sequentially depositing specie (1) and (2) onto the same support.

Abstract: Fine, pure, boehmite alumina crystallites are peptized, partially precipitated and phosphated, hardened, and dried to form a xerogel. The alumina can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Abstract: Fines are reduced in refractory materials by mixing the refractory material with an acid composition in a liquid polar organic compound and thereafter working the mixture until a decrease in volume occurs. The resulting product can be shaped and subjected to conventional finishing treatments. The resulting product exhibits reduced fines and thus is an improved material for use as a catalyst support. The resulting catalyst is of particular utility in the production of film grade ethylene polymer.

Abstract: An alumina-containing material is phosphated with mono- and dialkylphosphate esters. These partial phosphate esters are produced by a solvolysis reaction of a phosphorus compound and an alcohol. The phosphated alumina-containing material, when combined with a transition metal, such as chromium, can be used as a polymerization catalyst system to polymerize mono-1-olefins.

Abstract: Olefins are polymerized with a catalyst composition which forms on mixing a supported chromium oxide catalyst system and a silane compound. This composition allows the production of one or more comonomers in-situ. The resultant polymer has a lower density, a higher melt index, and a higher high load melt index than polymers produced with a similar catalyst system in the absence of a silane compound.

Abstract: Improved mixed chromium catalysts useful in particle form polymerizations to produce readily processable high density polyolefin resins which also have high resistance to environmental stress cracking are provided. First and second chromium-containing catalyst components obtained using silica supports of different pore volumes and wherein one of the catalyst components also contains aluminum are employed for the preparation of the mixed catalysts. The polymerization process and products obtained using the above-described mixed catalysts are also described.

Abstract: A process for (co)polymerizing alpha-olefins in the gas phase in a fluidized bed or mechanically stirred bed reactor using a Ziegler-Natta type catalyst or a heat activated chromium oxide/refractory oxide catalyst wherein the (co)polymerization is carried out in the presence of 0.005 to 0.2 weight %, based on the weight of the (co)polymer bed, of an inert pulverulent inorganic substance (e.g. silica) having a mean particle diameter between 0.5 and 20 microns. The process is capable of being operated at temperatures closer to the softening point of the produced polyolefin than in the absence of the pulverulent solid.

Abstract: A copolymer of ethylene and a higher alpha-olefin, preferably 1-hexene and/or 4-methyl-1-pentene, can be produced using an activated and subsequently carbon monoxide reduced chromium containing catalyst and a trialkyl boran cocatalyst. The polymerization process must be carefully controlled to produce a copolymer resin that can be made into a tough, impact resistant film.

Abstract: An alumina-containing material is phosphated with mono- and dialkylphosphate esters. These partial phosphate esters are produced by a solvolysis reaction of a phosphorus compound and an alcohol. The phosphated alumina-containing material, when combined with a transition metal, such as chromium, can be used as a polymerization catalyst system to polymerize mono-1-olefins.

Abstract: A modified supported catalyst for polymerizing alpha-olefins, for example, ethylene, is prepared by combining a chromium compound-containing catalyst with a modifier which is an oxide of an element of Group II A of the Periodic Chart of the Elements. The resulting modified catalyst composition, when used to polymerize alpha-olefins, produces polymer resins having higher values of High Load Melt Index (I.sub.21) than catalyst compositions without the modifier.There is also disclosed a process for polymerizing alpha-olefins, at relatively lower temperatures than was heretofore possible, to obtain resins of relatively high HLMI, using the above-identified modified catalyst composition. The resulting polymers can be used for the fabrication of blow-molded products, e.g., household and industrial containers.

Abstract: The present invention relates to a process for the polymerisation of ethylene or copolymerisation of ethylene and at least one other alpha-olefin, in the gas phase in a fluidised bed reactor, in the presence of a catalyst comprising chromium compounds associated with a granular support comprising a refractory oxide and activated by thermal treatment, which process is characterised in that the catalyst is used in the form of active particles of prepolymer, obtained by bringing the said catalyst in contact with ethylene, alone, or in a mixture with at least one higher alpha-olefin, in such a way that the prepolymer contains from 4.times.10.sup.-5 to 3 milligram atoms of chromium in the catalyst per gram.

Abstract: Process for gas phase polymerization of olefins using a highly active catalyst in a fluidized bed reactor (1), comprising a recator body (2) partially occupied by the fluidized bed and surmounted by a disengagement chamber (3). The gas mixture withdrawn from the disengagement chamber (3) is fed to a dust separator (6) e.g. a clycone, to separate the fine particles entrained by the gas. The gas is cooled, compressed and recycled to the base of the reactor. The particles are withdrawn from the dust separator (6) by a mixing device (8) which mixes the particles with a carrier gas. The carrier gas and particles are recycled to the reactor where they are introduced into the reactor body (2) through an opening in the side wall thereof at a position above the fluidized bed, but below the disengagement chamber (3). The velocity of the particles introduced into the reactor is insufficient to cause them to be blown directly into the bed.

Abstract: Ethene homopolymers and ethene copolymers with minor amounts of higher .alpha.-monoolefins are prepared by polymerization of the monomer or monomers using a chromium trioxide catalyst which is obtained by a method in which (1) a finely divided, porous, silicate carrier is laden with (2) chromium trioxide or a chromium compound which is converted to chromium trioxide under the conditions of stage (3), and then (3) the intermediate resulting from stage (2) is heated in an oxygen-containing gas stream. In this process, a cocatalyst which consists of a lithiumalkyl used in addition to the chromium trioxide catalyst.

Abstract: A catalyst system is produced by first forming a chromium catalyst on a predominantly silica support, activating in an oxygen-containing ambient and thereafter subjecting the thus activated composition to carbon monoxide reduction. The resulting reduced supported chromium catalyst composition is then precontacted with a cocatalyst selected from trialkyl boron compounds and dialkyl aluminum alkoxide compounds, preferably triethyl borane and thereafer contacted with ethylene. This results in a catalyst system which produces comonomer in situ so as to give tough, flexible ethylene copolymers from an essentially pure ethylene feed.

Abstract: A catalyst system useful for the polymerization of ethylene and other .alpha.-olefins comprising (a) a silica-supported chromium oxide catalyst and (b) a dihydrocarbylboron monohydrocarbyloxide adjuvant. The catalyst system results in .alpha.-olefin polymers having a broadened molecular weight distribution in the high molecular portion.

Abstract: Alumina is calcined and thereafter given a phosphating treatment. The resulting composition is particularly suitable for a support for a transition metal compound such as chromium oxide to provide an olefin polymerization catalyst. The resulting catalyst is capable of producing polymer at unusually high productivity rates and also gives the ability to produce high melt flow polymer.

Abstract: Device and process for introducing a powder with catalytic activity into a fluidized bed polymerization reactor (1), the said device comprising:a storage enclosure (2) for powder with catalytic activity, provided with a feed line (3) for powder with catalytic activity and a shut-off valve (26), this enclosure being connected to a metering device (4) making it possible to deliver periodically a given volume of powder with catalytic activity,an intermediate chamber (5), placed below the metering device to receive direct the powder delivered by the latter, this intermediate chamber comprising in its upper part a tube (6) bringing in an inert carrier gas, provided with a shut-off valve,piping for conveying the powder (8) connecting the bottom part of the intermediate chamber to the fluidized-bed reactor, this piping having a portion which is more or less horizontal, the said powder conveying piping being provided with a full-bore rapid-opening valve (10).

Abstract: The catalyst system is produced by first forming a chromium catalyst on a predominantly silica support, activating in an oxygen-containing ambient and thereafter subjecting the thus activated composition to carbon monoxide reduction. The resulting reduced supported chromium catalyst composition is then precontacted with a cocatalyst selected from trialkyl boron compounds and dialkyl aluminum alkoxide compounds, preferably triethyl borane and thereafter contacted with ethylene. This results in a catalyst system which produces comonomer in situ so as to give tough, flexible ethylene copolymers from an essentially pure ethylene feed.

Abstract: Ethene polymers are prepared by Phillips catalysis using (1) a supported catalyst which is loaded with chromium and titanium and (2) a co-catalyst, (1) having been obtained by preparing (1.1) a chromium- and titanium-loaded catalyst intermediate from (1.1.a) a silicate carrier material, (1.1.b) a selected chromium compound and (1.1.c) a selected titanium compound and then (1.2) heating said catalyst intermediate in an oxygen-containing gas stream, the (1) used having been obtained by, in general terms, (1.1) preparing in the first stage (1.1.1) a suspension from (1.1.1.1) a finely divided silicate carrier material and (1.1.1.2) a liquid alkane, (1.1.2) then (1.1.2.1) combining the suspension resulting from (1.1.1.) with (1.1.2.2.) a finely divided chromium trioxide, (1.1.3) thereupon (1.1.3.1) combining the suspension obtained from (1.1.2) with (1.1.3.2) an alkanol, (1.1.4) thereafter (1.1.4.1) combining the suspension formed in (1.1.3) with (1.1.4.2) a titanium compound of the formula Ti(OR).sub.

Abstract: Ethane polymers are prepared by Phillips catalysis using (1) a supported catalyst which is laden with chromium, phosphorus and titanium and (2) a cocatalyst, (1) being obtained by a procedure in which (1.1) a catalyst intermediate laden with chromium, phosphorus and titanium is prepared from a silicate carrier, a selected chromium compound, a selected phosphorus compound and a selected titanium compound, and (1.2) the catalyst intermediate is then heated in an oxygen-containing gas stream. In the process, the supported catalyst (1) used is one which is obtained (using specific methods and substances in each case) by a procedure in which (1.1) in a first stage (1.1.1), a suspension is first prepared from (1.1.1.1) a finely divided silicate carrier and (1.1.1.2) an inert organic solvent, (1.1.2) a suspension is then prepared from (1.1.2.1) a finely divided chromium trioxide and (1.1.2.2) an inert organic solvent, (1.1.3) thereafter (1.1.3.1) the suspension resulting from (1.1.2) is combined with (1.1.3.

Abstract: An improved method for reducing the acrylamide present water-in-oil emulsions of acrylamide polymers with amidase which comprises adding the amidase to the water-in-oil emulsion of the acrylamide polymer upon completion of its polymerization and then subjecting the thus treated water-in-oil emulsion to one or more of the following steps:(a) pH adjustment(b) heating(c) inert gas sparging(d) adding a chemical reducing agent.

Abstract: Novel high pore volume, high purity alumina gels and catalysts prepared therefrom are provided by a unique alumina gel preparation comprising hydrolyzing an aluminum alcoholate in a medium of a mixture of water and acetone, aging the resultant product and thereafter washing with acetone. Processes for the polymerization of olefins utilizing the afore-described alumina gels are also included herein.

Abstract: A catalyst support based on aluminum polyphosphate or polyphosphoric acid-impregnated alumina is provided by two alternative techniques. In the first embodiment, an aluminum polyphosphate composition is heated in a dry atmosphere and thereafter impregnated with a zerovalent chromium component under anhydrous conditions. The resulting catalyst is active for olefin polymerization. In the second embodiment, alumina is impregnated with a polyphosphoric acid composition. This resulting polyphosphoric acid impregnated alumina can be used as a support for zerovalent chromium or can be impregnated with a chromium component and oxidized to give an active hexavalent chromium species. The resulting catalysts are advantageous because of their unusual sensitivity to hydrogen thus allowing great leeway in molecular weight control.

Abstract: Density and flexural modulus of olefin polymers can be controlled using a chromium catalyst on a iron and aluminum phosphate and/or polyphosphate gel base.

Abstract: Ethylene polymer is particularly suitable for the production of tough film is produced under slurry conditions using a fluorided aluminophosphate support and a reaction temperature within the range of 93.degree. to 107.degree. C. in the presence of hydrogen and a small amount of trialkyl boron cocatalyst wherein said aluminophosphate has a phosphorous to aluminum ratio within the very narrow range of 0.15 to 0.4 and wherein said aluminophosphate carrying chromium catalyst is being activated at a temperature within the range of 482.degree. to 704.degree. C. The resulting film is not only substantially superior to film made from the best of the readily available commercial resins but is also better than film made from polymers using a similar catalyst system without the specific combination of parameters of this invention.

Abstract: Process for selective production of polyolefin resins of controlled rheology responsive to catalyst morphology in heat activated aluminum treated porous supports e.g., silica gel of regulated moisture content.

Abstract: A method of polymerizing olefins comprising contacting an olefin or mixture of olefins with a catalyst prepared with large pore volume zirconia-silica catalyst supports. The supports are prepared by reacting a zirconium compound of the formula M.sub.4 Zr(C.sub.2 O.sub.4).sub.4.nH.sub.2 O, where M is an alkali metal or ammonium ion and n equals 0 to 10, with a silicon compound of the type A.sub.2 SiO.sub.3, where A is an alkali metal, in an aqueous solution at a pH equal to at least 11, then adding an acidic solution to a pH of about 5-9 to produce a hydrocogel. The hydrocogel is then aged and washed free of soluble by-products with an aqueous washing agent. Water is removed from the washed hydrocogel by azeotropic distillation or by washing with a water miscible solvent and then calcining the resulting xerocogel.

Abstract: The present invention provides a synthetic amorphous zirconium-bonded silicate obtained by reacting, as main starting materials, a water-soluble alkali-metal silicate with an inorganic zirconyl salt and a mineral acid, in which zirconium is bonded to silica at the ratio of ZrO.sub.2 to SiO.sub.2 being 0.1 to 10 weight percent, which silicate is useful as a dentifrice base material and also as a filler for rubber.