137 results about "Aluminoxane" patented technology

The invention provides an active carrier, a supported metallocene catalyst, a preparation method and application. The invention relates to an active carrier, which is used for loading a metallocene compound to form a loaded metallocene catalyst, and comprises a carrier body and an ether-modified aluminoxane compound loaded on the carrier body, the ether-modified aluminoxane compound is modified with at least one of an alkyl ether having an alkyl carbon chain having 10 or more carbon atoms and a crown ether. The aluminoxane compound is modified by ether, so that the usage amount of the aluminoxane compound when the active carrier is used for preparing the supported metallocene catalyst can be reduced, the preparation cost of the supported metallocene catalyst is further reduced, and the supported metallocene catalyst can maintain relatively high catalytic activity.

The invention discloses a method for preparing methylaluminoxane by directly hydrolyzing trimethyl aluminum and a reaction device, and belongs to the technical field of chemical products. Comprising the following steps: introducing low-temperature methane gas containing gas-phase water into a trimethylaluminum organic solution, carrying out hydrolysis reaction under the dual effects of ultrasonic vibration and mechanical stirring and mixing, and filtering to remove solid substances after the reaction is completed, so as to obtain a methylaluminoxane solution. According to the method for preparing methylaluminoxane through direct hydrolysis of trimethyl aluminum, the hydrolysis quality of methylaluminoxane can be guaranteed, generation of gels such as aluminum hydroxide is effectively controlled, and the product yield is greatly increased; and the byproduct methane is high in purity, can be recycled and is free of environmental pollution and energy waste, so that the production cost is remarkably reduced.

The invention relates to the technical field of catalytic synthesis, in particular to a preparation method and polymerization application of a carbon nanotube-based double-cyclopentadienyl bridged metallocene catalyst, and the preparation method comprises the following steps: 1, acidizing a carbon nanotube; 2, dispersing the acidified carbon nanotubes in a methylaluminoxane solution in a nitrogen or inert gas atmosphere to obtain an acidified carbon nanotube dispersion liquid; and 3, mixing the double-cyclopentadienyl bridged metal compound solution with the acidified carbon nanotube dispersion liquid for reaction. According to the invention, the carbon nanotubes are added into an olefin polymerization reaction system in the form of a double-metallocene bridged metallocene catalyst carrier, so that the tensile strength and toughness of polyolefin are improved while olefin polymerization reaction is catalyzed with high catalytic activity.

The invention relates to ultra-high molecular weight polyethylene easy for subsequent processing and application, which is high in bulk density, narrow in particle size distribution and good in flowability, and comprises two polyethylene components with different molecular weights, one is ultra-high molecular weight polyethylene (called U segment) with viscosity average molecular weight of 2 million-10 million g / mol, and the other is ultra-high molecular weight polyethylene (called U segment) with viscosity average molecular weight of 2 million-10 million g / mol. The other one is low-weight-average molecular weight polyethylene (called L segment) with the weight-average molecular weight of 10,000-50,000 g / mol, and the mass ratio of the U segment to the L segment is (1-50): 1. The preparation method comprises the following steps: by taking a supported polyethylene catalyst as a main catalyst, one or more of alkyl aluminum, halogenated alkyl aluminum or aluminoxane as a cocatalyst and an alkane solvent with a boiling point of 0-90 DEG C or a mixed alkane solvent with saturated vapor pressure of 4-200KPa at 20 DEG C as a polymerization solvent, firstly preparing an ultra-high molecular weight polyethylene component through homopolymerization or copolymerization; and continuously preparing a homopolymerized or copolymerized low-weight-average molecular weight polyethylene component to obtain the ultra-high molecular weight polyethylene disclosed by the invention. The method has the characteristics of flexible production mode, excellent product processability and the like.

Disclosed in the present invention is a composition for preparing a vinyl block copolymer, the composition comprising: a first monomer ethylene, a second monomer a C3-C20 α-olefin and at least one regulation monomer, the regulation monomer being an olefin or a substituted olefin with the C atom number greater than 3, or styrene / a styrene derivative, and in the same composition, the second monomer being different from the regulation monomer. The composition is catalyzed by a main catalyst and a co-catalyst to obtain the vinyl block copolymer, wherein the main catalyst is a complex L-MR1R2R3 that contains three substituents and that is formed by an IVB-group metal and a monoanionic ligand, and the co-catalyst includes alkyl aluminum, polymerized or oligomerized aluminoxane, a neutral Lewis acid, a non-polymer, a non-coordinated ionic compound, or a mixture of two or more described above. Provided in the present invention is a composition capable of obtaining a lower-olefin block copolymer, the composition can obtain a lower-olefin block copolymer without the need of replenishing monomers or adding a chain transfer reagent for polymerization during polymerization processes, so that a production process is simple and involves low cost.

The invention relates to a supported double-center metallocene catalyst, which comprises a modified silicon-based carrier, a chromium-metallocene metal and other metallocenes, and the modified silicon-based carrier is a silicon-based carrier modified by an aluminum-based substance and a fluorine-containing substance. According to the catalyst, the carrier is modified, so that the chromium-metallocene metal can be better loaded, the catalyst is used for preparing polyethylene, and the polyethylene has wider molecular weight distribution. In the preparation process of polyethylene, under the condition that alkylaluminoxane is not used, bimodal polyethylene with wide molecular weight distribution can also be obtained.

The present invention relates to a narrow-distribution low-branching polyethylene wax and a preparation method thereof. A solvent, ethylene, a catalyst and a cocatalyst are added into a reaction kettle for polymerization reaction. After the polymerization reaction is completed, post-treatment is carried out to obtain a polyethylene wax product. The catalyst is a late transition metal catalyst with isatin as the skeleton, the cocatalyst includes an alkylaluminoxane, and the molar ratio of the catalyst to the cocatalyst is 1:100-600. Compared with the prior art, the present invention uses a late transition metal catalyst with high activity and high thermal stability to prepare a polyethylene wax with excellent performance. The obtained polyethylene wax has a moderate molecular weight, a narrow molecular weight distribution and a small degree of branching.

The present invention provides a modified catalyst and a preparation method thereof, a polyolefin elastomer and a preparation method and application thereof. The modified catalyst comprises a catalyst matrix and a coating layer coated on the outer surface of the catalyst matrix. Among them, the catalyst matrix is a metallocene catalyst, and the metallocene catalyst comprises a dichlorodicyclopentadienylzirconium main catalyst and a butylaluminoxane cocatalyst, and the coating layer material is a low-carbon olefin homopolymer. The polyolefin elastomer prepared by the present invention has improved uniformity of comonomer insertion into the molecular chain segment and enhanced light transmittance of the product, making its industrial application prospect broader.

A process for producing a supported single-site catalyst is provided. The process comprises forming a slurry comprising a dried inorganic oxide support, an organic solvent, and an aluminoxane activator; maintaining the temperature of the slurry from about 100° C. to about 200° C. for a time period from about 0.5 to about 10 hours to form a supported aluminoxane slurry; and contacting N the supported aluminoxane slurry with a single-site catalyst component to form a supported single-site catalyst. The organic solvent comprises one or more non-aromatic organic compounds having a boiling point of about 100° C. or greater in an amount of about 50 CA wt. % or greater with respect to the total amount of the organic solvent.

The present application provides a kind of Ziegler-Natta catalyst for preparing high molecular weight polyethylene with narrow molecular weight distribution, porous polymer microspheres are used as carrier, load the Ziegler-Natta catalyst doped with trace metallocene, the doping amount of metallocene is 0.01-2wt% of the amount of Ziegler-Natta catalyst.The preparation method includes the reaction of porous polymer microspheres with alkyl magnesium chloride, then with aluminoxane compound, then the product is reacted with titanium tetrachloride, finally, add metallocene to the product to obtain Ziegler-Natta catalyst.The present application uses porous polymer microspheres as carrier, dopes trace metallocene in Ziegler-Natta catalyst, and the composite catalyst prepared is used for the synthesis of high molecular weight polyethylene, and high molecular weight polyethylene with narrow molecular weight distribution can be obtained, which can meet the application needs of lithium ion battery separator materials.

The invention relates to ethylene homopolymerized wax and a polymerization preparation method thereof. The invention relates to a polymerization preparation method of ethylene homopolymerized wax. The method comprises the following steps: under a catalytic system comprising one or more of a non-metallocene catalyst and a metallocene catalyst as a main catalyst and one or more of aluminoxane, boride, aluminum alkyl and aluminum alkyl chloride as a co-catalyst, carrying out a reaction on the main catalyst and the co-catalyst, ethylene is subjected to a polymerization reaction in the presence of hydrogen in an alkane solvent having a boiling point of 0-90 DEG C or a mixed alkane solvent having a saturated vapor pressure of 4-200 KPa at 20 DEG C as a polymerization solvent (preferably an alkane solvent having a boiling point of 25-82 DEG C or a mixed alkane solvent having a saturated vapor pressure of 30-160 KPa at 20 DEG C as a polymerization solvent). The ethylene homopolymer is narrow in molecular weight distribution, high in crystallinity, low in needle penetration, high in devolatilization efficiency and low in ash content, and the ethylene homopolymer wax shows excellent dispersity in the application of the color master batch and is excellent in processing performance.

The invention provides a preparation method of an antistatic metallocene catalyst. The method comprises the following steps: carrying out thermal activation treatment on a silica gel carrier; loading alkyl tin chloride on the silica gel carrier to obtain an alkyl tin chloride modified silica gel carrier; adding methylaluminoxane into the alkyl tin chloride modified silica gel carrier to obtain a methylaluminoxane / alkyl tin chloride modified silica gel carrier; adding a metallocene compound into the methylaluminoxane / alkyl tin chloride modified silica gel carrier for heating reaction, and then adding an antistatic agent to obtain the antistatic metallocene catalyst. Alkyl tin chloride is used for modifying a silica gel carrier and reacts with hydroxyl to greatly eliminate the hydroxyl; the loading capacity can be improved by combining with MAO, and metallocene combination sites can be increased; after the antistatic agent is added, static electricity generated in the reaction process is reduced, the flaking phenomenon is reduced, and the static electricity range can be controlled to be + / -0.02 KV.

Improved preparation process for silica supported catalyst systems, which comprise a specific class of metallocene complexes in combination with a boron containing cocatalyst and an aluminoxane cocatalyst and use of the new, improved catalyst system.

The application discloses a method for selectively oligomerizing ethylene. The method comprises the following steps: filling ethylene into a reaction kettle which is replaced by nitrogen, adjusting temperature and pressure to reaction temperature and reaction pressure; adding a main catalyst and a cocatalyst composition into the reaction kettle to carry out an ethylene oligomerization reaction; after the reaction is completed, temperature and pressure are reduced, and a termination agent is used to terminate the reaction; the molar ratio of total boron and aluminum in the main catalyst and the cocatalyst composition is 1:0.1-7000; the main catalyst is formed by a ligand and a transition metal compound, and the molar ratio of the ligand and the transition metal compound is 0.5-1.5:1. The cocatalyst composition comprises an organic boron compound, an alkyl aluminum compound and an alkyl aluminum oxide compound.

The invention provides a supported metallocene catalyst, a preparation method of the supported metallocene catalyst, an ethylene homopolymerization reaction method and an ethylene and alpha-olefin copolymerization reaction method. The supported metallocene catalyst comprises a carrier, and a metallocene compound and a cocatalyst which are supported on the carrier, the carrier is selected from silicon dioxide and / or aluminum oxide; the metallocene compound has a structure as shown in a formula I. Formula I. The polymer particles are regular, and the phenomenon that the reactor adheres to the kettle is relieved; in addition, when the supported metallocene catalyst is used for copolymerization of ethylene and alpha-olefin by adopting a slurry polymerization process, the polymerization activity can be improved, the cost is reduced, and the dosage of methylaluminoxane is reduced.

The invention discloses a supported metallocene catalyst and a preparation method and application thereof, the supported metallocene catalyst comprises a mixture and / or a reaction product of the following components: (A) a reaction mixture of modified alkylaluminoxane and a modified compound, the modified compound being selected from at least one of benzoic acid and substituted benzoic acid; (B) a carrier; (C) a metallocene compound; and (D) an alkane. The supported metallocene catalyst disclosed by the invention is completely prepared by using an alkane solvent, so that the problems caused by using an aromatic hydrocarbon solvent are avoided, the production process of the catalyst is simplified, and industrial implementation is facilitated. The content of Al in the prepared catalyst is larger than 6% by weight, the content of transition metal elements is 0.05-1% by weight, the loading efficiency of the modified methylaluminoxane is improved, the catalyst is used for ethylene polymerization reaction, the performance is good, and the polymerization activity is obviously improved.

The invention relates to modified aluminoxane and a preparation method and application thereof.The preparation method of the modified aluminoxane comprises the following steps that S1, an oxygen-containing compound containing carbonyl and trimethyl aluminum are dispersed in an organic solvent and heated, a transparent solution without gel is formed, and an MAO solution is obtained; and S2, dropwise adding the MAO solution obtained in the step S1 into a trifluoroaryl boron compound solution, mixing, heating for reaction, and washing and drying an obtained precipitated solid to obtain the modified aluminoxane. Compared with the prior art, the method has the advantages that silicon dioxide and the like are not used as carriers, the alkylaluminoxane solution is prepared only through the non-hydrolysis reaction, and near-particulate solid alkylaluminoxane with the median diameter of 1-80 microns is separated out from the alkylaluminoxane solution, so that when the alkylaluminoxane is applied to a polyolefin catalytic system, the high activity of a catalyst can be maintained; the content of inorganic components in polyolefin is reduced, and the processability of a polymer is improved.

The invention discloses a preparation method of an alkylaluminoxane solution, and belongs to the field of alkylaluminoxane preparation. The method comprises the following steps: firstly, performing vacuum drying on an aluminum hydroxide solid at high temperature to remove moisture adsorbed by the aluminum hydroxide solid; then dispersing aluminum hydroxide in an anhydrous hydrocarbon solvent under anhydrous and anaerobic conditions, adding a hydrocarbon solution of trimethylaluminum, and preparing alkylaluminoxo alkyl substrate through double decomposition reaction of the aluminum hydroxide and the trimethylaluminum; and respectively adding aluminum alkyl and inorganic salt hydrate into the alkyl aluminoxane base, reacting at a set temperature, and filtering to remove inorganic salt by-products after the reaction is completed, thereby obtaining the alkyl aluminoxane solution. The method disclosed by the invention is mild in reaction, high in yield and few in byproducts.

The application discloses a preparation method of a single-center catalyst system and application thereof, and the preparation method comprises the following steps: (1) performing vacuum distillation on a modified methylaluminoxane solution, separating out a solvent and aluminum alkyl to obtain a solid product; (2) dissolving the solid product obtained in step (1) with a pentane solution to obtain a homogeneous solution with different aluminum contents; and (3) combining the homogeneous solution obtained in step (2) with a single-active-center catalyst to form a catalyst system. When the single-active-center catalyst system is used for preparing polyethylene wax, different solvents can be avoided from being introduced into a polymerization system, a process flow of the polyethylene wax is simplified, and energy consumption for solvent separation is reduced; reduction of active aluminum helps to improve polymerization activity, the obtained polyethylene wax has lower metal content and narrower molecular weight distribution, the devolatilization efficiency of the polyethylene wax is improved, and the obtained polymer has a VOCs content lower than 20 ppm.

The present invention relates to an efficient process for the preparation of highly active polymerization co-catalysts by reacting methylaluminoxane residues with C6-C18-alkyl aluminum compounds in the presence of a hydrocarbon solvent.

The invention provides an antistatic metallocene catalyst and application thereof. The antistatic metallocene catalyst comprises an antistatic agent / methylaluminoxane / alkyl tin chloride / silica gel carrier and a metallocene compound loaded on the carrier; the antistatic agent / methylaluminoxane / alkyl tin chloride / silica gel carrier is a silica gel carrier modified by an antistatic agent, methylaluminoxane and alkyl tin chloride. Alkyl tin chloride is used for modifying a silica gel carrier and reacts with hydroxyl to greatly eliminate the hydroxyl; the loading capacity can be improved by combining with MAO, and metallocene combination sites can be increased; after the antistatic agent is added, static electricity generated in the reaction process is reduced, the flaking phenomenon is reduced, and the static electricity range can be controlled to be + / -0.02 KV.

The invention provides a method and a system for treating methylaluminoxane gel. The method comprises the following steps: mixing cyclohexane of which the water content is not less than 100ppm and methylaluminoxane gel, and cleaning; the temperature of the cleaning treatment is not higher than 50 DEG C, and the cleaning treatment is carried out at the stirring rotating speed of 50-500rpm. According to the method, gel gathered on the olefin oligomerization cocatalyst storage tank can be removed, and the activity of the catalyst is not influenced.

The present invention relates to a catalytic composition for the selective oligomerisation of ethylene, in particular for the the tetramerisation of ethylene into 1-octene, wherein the catalytic composition comprises: - a chromium-based metal precursor; - a heteroatomic ligand; - methylaluminoxane supported on an inorganic support; - an additive in the form of an aluminium-based compound; wherein the composition has a molar ratio of the aluminium of the methylaluminoxane supported on an inorganic support to the chromium of the metal precursor of greater than 250, and a molar ratio of the aluminium of the additive to the chromium of the metal precursor of greater than 200.

Forming a catalyst system in the absence of aromatic solvents may be desirable. Catalyst systems effective for olefin polymerization may comprise a support material, an aluminum oxane formed in situ on the support material from a trialkylaluminum compound and water in the absence of aromatic solvents such as toluene, and a metallocene with C1 symmetry and containing a Group 4 metal. To form the catalyst system, the support material can be slurried in an aliphatic hydrocarbon solvent in the presence of water and contacted with a trialkylaluminum compound to form a supported activator, and the supported activator can be contacted with a metallocene with C1 symmetry and containing a Group 4 metal.

The invention discloses a method for continuously preparing alkylaluminoxane based on a non-hydrolysis method, and belongs to the field of alkylaluminoxane preparation. According to the method disclosed by the invention, a microreactor and a flow chemical technology are organically combined, so that the mixing, heat transfer and mass transfer efficiencies in the preparation process of alkylaluminoxane are improved, and the problems of low reaction efficiency, poor activity repeatability of different batches of products and the like in a synthesis technology based on a tank reactor are solved. The method is suitable for the reaction of aluminum alkyl and a gas-phase / liquid-phase compound containing carbon-oxygen bonds, the reaction temperature and the reaction time can be accurately controlled, the whole reaction process is safe and efficient, and the produced alkylaluminoxane product has high yield, high catalytic activity and high stability.

The invention relates to the technical field of cocatalyst preparation, and particularly provides alkylaluminoxane and a preparation method thereof. The preparation method of the alkylaluminoxane comprises the following steps: mixing metal salt containing crystal water with anhydrous alkali metal halide, grinding to form mixed crystals, and under the protection of inert atmosphere and inert solution, enabling the mixed crystals to be in contact and react with alkylaluminoxane to obtain the alkylaluminoxane. The alkylaluminoxane and the preparation method provided by the invention are used for realizing synthesis of alkylaluminoxane with high yield, high safety and high storage stability.

The invention provides a metallocene polyethylene catalyst, a preparation method, application and related products, and belongs to the technical field of catalytic chemistry. The metallocene polyethylene catalyst provided by the invention is prepared from a metallocene compound, methylaluminoxane and modified silica gel, the surface of the modified silica gel is modified by a silicate ester compound containing crown ether groups. Through surface modification of the crown ether functional group, on one hand, the loading effect of the silica gel carrier on the metallocene compound is improved, on the other hand, polar groups provided by the crown ether functional group can control static electricity generated in the stirring and mixing process of a reaction material mixture, and then product coalescence and shutdown inspection are reduced.

The application provides a metallocene catalyst composition for synthesizing low-viscosity poly-alpha-olefin. The catalyst composition is composed of quinoline-indene metallocene as a main catalyst and an organic boron reagent or an alkyl aluminum oxane reagent as a cocatalyst and application thereof. The metallocene catalyst composition claimed by the application has the advantages of low dimer content in the product, high yield of lubricating oil component and overall yield when synthesizing poly-alpha-olefin; the synthesized low-viscosity lubricating oil base oil component has excellent viscosity-temperature performance and excellent low-temperature fluidity.

The present application relates to a method and device for preparing alkylaluminoxane by using a packed column water-carrying method. The method comprises: using a packed column to meter water, and injecting the water into a solution of alkylaluminum and a first inert organic solvent under the driving of a mobile phase to react, thereby obtaining a mixed solution containing alkylaluminoxane. The method uses the technology of a packed column which can carry out trace metering of water, so that the amount of water relative to the amount of alkylaluminum in the inert organic solvent solution can maximize the generation of alkylaluminoxane rather than aluminum hydroxide compounds or aluminum trioxide. In the experimental operation, relevant configurations and operation technologies are combined, so that the reaction is smoothly and controllably carried out, and alkylaluminoxane is prepared at a high yield.

The present invention relates to a method for the oligomerisation, preferably tetramerisation, of ethylene to octene-1, the method comprising a step of injecting into an oligomerisation reactor at least the following four compounds: - a chromium-based metal precursor; - a heteroatomic ligand; - methylaluminoxane supported on an inorganic support; - an additive in the form of an aluminium-based compound; wherein the chromium-based metal precursor and the heteroatomic ligand are never brought into contact with the methylaluminoxane supported on an inorganic support in the absence of the additive in the form of an aluminium-based compound.