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105 results about "Aluminoxane" patented technology

Aluminoxanes refer to compounds that are obtained by the partial hydrolysis of trialkylaluminium compounds. Aluminoxanes serve as activators for catalytic olefin polymerisation, such as the Ziegler–Natta catalyst. They also serve a function as scavenger for impurities (e.g. water) in reactions that are sensitive to these impurities.

Active carrier, supported metallocene catalyst, preparation method and application

PendingCN120795208ACarbon numberPolymer science
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.
Owner:SHANGHAI RES INST OF CHEM IND CO LTD +2

Method and reaction device for preparing methylaluminoxane by directly hydrolyzing trimethyl aluminum

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.
Owner:QUZHOU JIANHUA SANRUI NEW MATERIALS CO LTD

Preparation method and polymerization application of carbon nanotube-based double-cyclopentadienyl bridged metallocene catalyst

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.
Owner:SHANDONG JINGSHI DAZHAN NANO TECH CO LTD

Composition for preparing vinyl block copolymer

PCT designated stageWO2026056947A1Polymer scienceAluminoxane
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.
Owner:UNIV OF CHINESE ACAD OF SCI

A ziegler-natta catalyst for producing high molecular weight polyethylene with a narrow molecular weight distribution and a method for producing the same

ActiveCN116854840BBulk chemical productionAluminoxaneZiegler–Natta catalyst
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.
Owner:PARK SENJING NEW ENERGY MATERIALS (SHANGHAI) CO LTD

Ethylene homopolymerized wax and preparation method thereof

PendingCN121758656AAlkanePolymer science
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.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Preparation method of antistatic metallocene catalyst

PendingCN122071543AAluminoxanePtru catalyst
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.
Owner:PETROCHINA CO LTD

A process for the selective oligomerization of ethylene

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.
Owner:PETROCHINA CO LTD

Supported metallocene catalyst, preparation method thereof, ethylene homopolymerization method and ethylene and alpha-olefin copolymerization method

ActiveCN121293393APolymer scienceAluminoxane
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.
Owner:PETROCHINA SHANGHAI ADVANCED MATERIALS RESEARCH INSTITUTE CO LTD +1

Supported metallocene catalyst and preparation method and application thereof

PendingCN120718185ABenzoic acidAlkane
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.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Modified aluminoxane as well as preparation method and application thereof

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.
Owner:SHANGHAI RES INST OF CHEM IND CO LTD

Preparation method of alkylaluminoxane solution

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.
Owner:浙江智英石化技术有限公司

A single-site catalyst system, method of preparation and use

PendingCN122344280AAluminoxanePtru catalyst
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.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Antistatic metallocene catalyst and application thereof

PendingCN122071542APolymer scienceAluminoxane
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.
Owner:PETROCHINA CO LTD

Treatment method and system of methylaluminoxane gel

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.
Owner:PETROCHINA CO LTD

Supported metallocene catalyst systems for olefin polymerization without aromatic solvent and related methods

PendingCN122341660APolymer scienceAluminoxane
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.
Owner:EXXONMOBIL RESEARCHK & ENG CO

Alkyl aluminoxane and preparation method thereof

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.
Owner:CHINA CHEM TECH RES INST

A metallocene catalyst composition for synthesizing low viscosity polyalphaolefins

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.
Owner:SINOCHEM QUANZHOU PETROCHEM CO LTD +1

A process and apparatus for the preparation of alkylaluminoxanes using packed column water phase transfer

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.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Preparation method and application of modified alkyl aluminoxane

The invention provides a preparation method and application of modified alkyl aluminoxane. Comprising the following steps: carrying out first reaction on paraformaldehyde and trialkyl aluminum in a solvent to obtain a precursor solution; performing pyrolysis treatment on the precursor solution to obtain a solution containing alkylaluminoxane; and adding acetone into the solution containing alkylaluminoxane, and carrying out a second reaction at 0-100 DEG C to obtain the modified alkylaluminoxane. The method is beneficial to reducing the content of free alkyl aluminum in the modified alkyl aluminoxane.
Owner:WANHUA CHEM GRP CO LTD

A high molecular weight propylene-based elastomer toughened polypropylene blend composite and a method for making the same

The present application relates to polypropylene material and its preparation method, disclose a kind of high molecular weight propylene-based elastomer toughened polypropylene blend composite material and its preparation method;Its preparation method is, using high molecular weight propylene-based elastomer toughened polypropylene, the high molecular weight propylene-based elastomer is by propylene monomer and its comonomer (1-butene, styrene, 1-hexene, 1-octene, 1-decene and the like one or several) preparation by quinoline amine-based binuclear metal hafnium catalyst and cocatalyst (three five fluorophenyl boron, triphenyl carbonium tetrakis (five fluorophenyl) borate, aluminoxane, alkyl aluminum, alkyl aluminum chloride and the like one or several);While meeting the improvement PP toughness, keep its excellent strength and rigidity, and continue to give its excellent low temperature toughness, specifically, after toughening modification, the toughness of polypropylene-based blend composite material at room temperature (25 DEG C) and low temperature (-25 DEG C) are obviously improved, simultaneously, its tensile strength changes little.Therefore, the present application has originality innovation, provides new direction for the development of polyolefin material field.
Owner:QINGDAO UNIV OF SCI & TECH

A catalyst system for ethylene oligomerization reaction and its preparation method and application

The present invention provides a catalyst system for ethylene oligomerization reaction, its preparation method and application, the catalyst system comprising cyclohexane and a metal complex of 2-formyl-1,10-phenanthroline chloride condensation 2,6-dimethylaniline and ethylaluminoxane dissolved in the cyclohexane. The present invention adopts ethylaluminoxane as an aluminum adjuvant and cyclohexane as a solvent, which can effectively increase the temperature of the ethylene oligomerization reaction when using the metal complex catalyst of 2-formyl-1,10-phenanthroline chloride condensation 2,6-dimethylaniline. At the same time, the ethylene oligomerization reaction can be initiated rapidly, run smoothly, have good repeatability, and the catalyst has high catalytic activity.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Catalysts for the selective oligomerization of ethylene comprising saturated aliphatic cyclic backbone bisphosphine ligands and their preparation and use

The application relates to an ethylene selective oligomerization catalyst containing a saturated aliphatic ring skeleton biphosphine ligand and preparation and application thereof, the catalyst comprising a ligand, a transition metal compound and an activator, the chemical structural formula of the ligand being: wherein the groups R 1 to R 4 are each independently hydrogen, an alkyl group, an alkoxy group, an alkenyl group or an aromatic group; n is a positive integer, and the value range is 3-5; the transition metal in the transition metal compound is selected from iron, cobalt, nickel, copper, titanium, vanadium, chromium, manganese, molybdenum, tungsten or palladium; and the activator comprises an alkyl aluminum compound, an aluminoxane compound or an organic boron compound. Compared with the prior art, the catalyst provided by the application has higher catalytic activity and total selectivity of 1-hexene / 1-octene, and the polymer content is lower, so that the production cost is greatly reduced, the requirements of the industrial department can be met, and the catalyst has important application value.
Owner:EAST CHINA UNIV OF SCI & TECH +1

A supported metallocene catalyst, its preparation method and application

This invention belongs to the field of olefin polymerization technology and discloses a supported metallocene catalyst, its preparation method, and its application. The catalyst comprises a support and a metallocene compound and an alkylaluminoxane supported on the support. The support is a spherical pyrophyllite-clay composite material with three-dimensional cubic channels, made of mesoporous clay silica, silica gel, and pyrophyllite clay minerals. The metallocene compound has the structure shown in Formula 1, where R1, R2, R3, R4, R5, R1', R2', R3', R4', and R5' are each independently hydrogen or a C1-C5 alkyl group, and at least one of R1, R2, R3, R4, and R5 is a C1-C5 alkyl group, at least one of R1', R2', R3', R4', and R5' is a C1-C5 alkyl group, M is one of titanium, zirconium, and hafnium, and X is a halogen. The catalyst of this invention has a stable structure and high catalytic activity.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Catalyst composition comprising chromium and supported methylaluminoxane

PendingCN122374095AAluminoxanePtru catalyst
This invention relates to catalyst compositions for the selective oligomerization of ethylene, particularly for the tetramerization of ethylene into 1-octene, comprising: - a chromium-based metal precursor; - a heteroatom ligand; - a supported methylaluminoxane on an inorganic support; - an additive in the form of an aluminum-based compound; wherein the composition has a molar ratio of aluminum in the supported methylaluminoxane on the inorganic support to chromium in the metal precursor greater than 250, and a molar ratio of aluminum in the additive to chromium in the metal precursor greater than 200.
Owner:IFP ENERGIES NOUVELLES

Synthetic method of oligomerized methylaluminoxane

The invention discloses a synthesis method of oligomerized methylaluminoxane. According to the method, alkyl aluminum of C2 or above is used as a starting raw material, n value distribution of generated MAO can be effectively controlled, high-oligomerization-degree MAO small in molecular weight distribution range and narrow in n value distribution is obtained, the MAO product catalytic activity is relatively concentrated, the method is especially suitable for a process for preparing high-carbon alpha-olefin through ethylene oligomerization, and the selectivity of target alpha-olefin can be remarkably improved.
Owner:CHINA CHEM TECH RES INST

A method for high temperature preparation of low entangled ultra-high molecular weight polyethylene

PendingCN122356340APolymer scienceAluminoxane
This invention discloses a method for preparing low-entanglement ultra-high molecular weight polyethylene using an ONN-type Group IV metal catalyst at high temperature. Using methylaluminoxane (MAO) as a co-catalyst, homopolymerization of ethylene is carried out at a polymerization temperature of 50-110 °C and an ethylene pressure of 10-40 atm to obtain a weight-average molecular weight polyethylene (MAH). M w (Greater than 2.5 × 10) 6 g·mol ‑1 Ultra-high molecular weight polyethylene (UHMWPE) was obtained. The resulting virgin particles exhibited a low-entanglement structure, specifically characterized by: a ≥90% decrease or disappearance of the high-temperature melting peak area after DSC annealing; a storage modulus that increased to more than twice its initial value over time during rheological testing at 160 °C; a lamellar or petal-like crystal morphology as shown by scanning electron microscopy; and the ability to be directly pressed into transparent self-supporting films at room temperature. The Ti1 / MAO system, at 110 °C and 40 atm, still yielded a molecular weight of approximately 2.0 × 10⁻⁶. 6 g·mol ‑1 The polyethylene produced exhibits a tensile strength of 40 MPa and an elongation at break of 576% after hot pressing. This invention enables the direct preparation of low-entanglement UHMWPE under industrial-grade high-temperature and high-pressure conditions, resulting in significantly superior processing performance compared to traditional highly entangled products.
Owner:QINGDAO UNIV OF SCI & TECH

Hydrocarbyl-modified methylaluminoxane cocatalyst for bisphenylphenoxy metal-ligand complexes

ActiveCN116194491BArylPolymer science
A method for polymerizing olefin monomers. The method comprises reacting ethylene and optionally one or more olefin monomers in the presence of a catalytic system, wherein the catalytic system comprises: AlR having a content of less than 50 mol% based on the total molar amount of aluminum. A1 R B1 R C1 Modified hydrocarbon methylaluminoxane, wherein R A1 R B1 and R C1 Independently for straight chains (C1-C) 40 Alkyl groups, branched (C1-C) 40 )alkyl or (C6-C 40 ) aryl; and one or more metal-ligand complexes according to formula (I).
Owner:DOW GLOBAL TECHNOLOGIES LLC