510 results about "Aluminum alkyl" patented technology

The invention discloses a domino catalyzing system of a primary metallocene catalyst, which takes ethane as a sole monomer to prepare branched polyethylene, and the application thereof, which relates to vinyl copolymer. the catalyzing system is a compound catalyzing system consisting of the single primary metallocene catalyst and two different catalyst promoters, wherein, the primary catalyst is a metallocene catalyst with a structural formula of Cp<1>MR<1>R<2>R<3>, Cp<1>Cp<2>MR<1>R<2> or Cp<1>-D-Cp<2>MR<1>R<2>; alkyl aluminium acts as an oligomerization catalyst promoter; methylaluminoxane or triisobutyl aluminium or triethyl aluminum that is not used together with the oligomerization catalyst promoter acts as a copolymerization catalyst promoter; the mole ratio between the oligomerization catalyst promoter and the primary catalyst is 10-1000 to 1, and the mole ratio between the copolymerization catalyst promoter and the primary catalyst is 20-1000 to 1. The catalytic activity of the metallocene domino catalyzing system for preparing the branched polyethylene is 5 multiplied by 10<5> to 5 multiplied by 10<7>gPE/(molM per hour), the degree of branching is 10-200/1000C, the molecular weight of the branched polyethylene prepared under the effect of the catalyzing system ranges from 1 multiplied by 10<5> to 4 multiplied by 10<5> and the melting point is below 120 DEG C or even no melting point exists.

The catalyst for olefin polymerization or copolymerization at high temperature consists of three components, including component A, component B and component C. The component A is solid prepared through dissolving magnesium chloride in organic epoxy compound or organic phosphorus compound to form solution, mixing the solution with titanium tetrahalide and separating assistant to separate soli, and treating with electron donor and titanium tetrahalide. The component B is mixture of aluminoxane and alkyl aluminum compound. The component C is organic silane. At polymerization temperature higher than 90 deg.c, the catalyst has high stereo selectivity and high activity.

The present invention relates to a catalytic system usable for the preparation of polybutadienes by polymerisation, to a process for the preparation of said catalytic system and to a process for the preparation of polybutadienes by means of this catalytic system.

A catalytic system according to the invention is based on at least:

• • a conjugated diene monomer,
  • an organic phosphoric acid salt of one or more rare earth metals, said salt being in suspension in at least one inert, saturated and aliphatic or alicyclic hydrocarbon solvent,
  • an alkylating agent consisting of an alkylaluminium of formula AlR₃ or HAlR₂, the “alkylating agent:rare earth salt” molar ratio being greater than 5, and
  • a halogen donor which belongs to the family of alkylaluminium halides with the exception of alkylaluminium sesquihalides,
  • and, according to the invention, said catalytic system comprises said rare earth metal(s) in a concentration equal to or greater than 0.005 mol/l.

The present invention relates to a cocatalyst composition and application thereof, in particular to a cocatalyst composition. The cocatalyst is characterized by comprising a reaction product of alkylaluminium and water, and alkyl aluminum, wherein based on A1, the molar ratio of the reaction product of the alkylaluminium and the water to the alkyl aluminum is 0.5: 1 to smaller than 4: 1. The present invention further relates to a catalyst system containing the cocatalyst composition, and application of the cocatalyst composition in non-metallocene complexe catalyzed chain alkene-cycloalkene copolymerization. Compared with the alkyl aluminum, the cost of the cocatalyst composition disclosed by the present invention is lower.

Alpha-olefins are manufactured in high yield and with very high selectivity by contacting ethylene with an iron complex of a selected 2,6-pyridinedicarboxaldehyde bisimine or a selected 2,6-diacylpyridine bisimine, and in some cases a selected activator compound such as an alkyl aluminum compound. Novel bisimines and their iron complexes are also disclosed. The alpha-olefins are useful as monomers and chemical intermediates.

A process for selectively producing 1-butene comprises contacting at least one antifouling agent with at least one aluminum alkyl compound to form at least one antifouling compound in a first step. The antifouling compound may comprise a structure comprising a central aluminum molecule bound to an R1 group, bound to an R2 group, and bound to an R3 group. The process further comprises feeding the antifouling compound, an additional amount of the aluminum alkyl compound, at least one titanate compound, and ethylene into a reactor to dimerize ethylene in a second step. The titanate compound is fed as a stream separated from the streams of the antifouling compound and the additional amount of the aluminum alkyl compound. The molar ratio of the sum of the aluminum alkyl compound to the titanate compound is equal to or higher than 1.5 and equal to or lower than 3.0.

The invention relates to a catalyst system of ultra-high molecular weight polyethylene, which comprises a magnesium compound carrier-supported titanium catalyst solid main component and an aluminum alkyl compound catalyst promoter component. The catalyst system of ultra-high molecular weight polyethylene is characterized in that carbon dioxide, alcohol and silicon compound are added to process the magnesium compound carrier in the preparation process of the catalyst solid main component, and the titanium content and the ester content in the catalyst system are adjusted by adjusting the addition of titanate in the processing of supporting titanium to change the growing ability of polymer on the catalyst active site, adjust the initial activity of the catalyst and improve the performance of the polymer. The catalyst has the advantage of simple preparation method, and is beneficial to industrial production. The particle diameter of ultra-high molecular weight polyethylene prepared by the catalyst is limited in a certain range, the generation of fine powder and coarse particles is reduced, and the stacking density is increased.

The invention relates to a preparation method of propylene polymer. The method comprises preparing the propylene polymer in the presence of a catalyst under a temperature of 80 to 150 DEG C, wherein the catalyst comprises a catalyst component, an aluminum alkyl compound and an external electron donor compound. The catalyst component is prepared by the following steps: (1) preparing an homogeneous solution; (2) contacting the solution obtained in the step (1) with a titanium compound and reacting in the presence of a precipitation aid agent to obtain a mixture; and (3) contacting the mixture in the step (2) with an internal electron donor, wherein the precipitation aid agent comprises a precipitation aid agent a which is a diol ester compound as shown in a formula (I), a precipitation aid agent b which is alkyl ester of aliphatic or aromatic carboxylic acid, a precipitation aid agent c which is a titanate compound, and a precipitation aid agent c which is 1,3-diether compound as shown in a formula (II), and a is different from b. The propylene polymer prepared by the invention has both high melt index and isotactic index.

The invention discloses a catalyst solid component for olefin polymerization. A preparation method of the catalyst solid component comprises the following steps of: fully reacting anhydrous magnesium halide, an alcohol compound, titanate and a lipid compound (an internal electron donor) which is shown as picture 1 in an alkane solvent to obtain stable and uniform alcohol compound solution; contacting and reacting the prepared alcohol compound solution and titanium halide; further adding the lipid compound shown as picture 1; and after filtering and washing, obtaining the catalyst solid component. The catalyst solid component is combined with aluminum alkyl and a silane compound to form a catalyst, which can be applied to olefin polymerization.

A cocatalyst system for olefin polymerization comprises an aluminoxane (especially methylaluminoxane, or “MAO”), an aluminum alkyl and a halogenated phenol. The preferred halogenated phenol is pentafluorophenol. The use of pentafluorophenol permits the substitution of a portion of the MAO cocatalyst (which is expensive) with inexpensive aluminum alkyl. The cocatalyst is most preferably employed in combination with an organometallic catalyst having at lease one pi ligand.

This invention relates to organoaluminum compounds, to organoaluminum activator systems, preferably supported, to polymerization catalyst systems containing these activator systems and to polymerization processes utilizing the same. In particular, this invention relates to catalyst systems comprising an ion-exchange layered silicate, an organoaluminum compound, and a metallocene.

The invention relates to a method used for olefin polymerization by using a plurality of serial polymerization reactors, which is characterized by comprising the following steps of: in the presence of catalysts, adding propylene into the reactors, and discharging generated polymers from outlets of the reactors. In the method, the generated polymer particles pass through reaction regions in a flow mode of piston flow; and at the outlets of the reactors, the generated polymers are all discharged, and back mixing in any mode cannot be generated. The used reactors are vertically arranged pipe reactors, and the flow mode of the fluid in the reactors is laminar flow. In one or more serially operated polymerization reactors, the first reactor is a prepolymerization reactor, the catalysts, aluminum alkyl, external electron donors and a small amount of hydrogen are added into the first prepolymerization reactor, the obtained prepolymer is added into a second reactor, and the generated polymer slurry is discharged from the outlets of the reactors.

The present invention relates to diarylphenoxyaluminum compounds which are obtainable by reacting a bis(diarylphenol) ligand of the formula (I)

with an alkylaluminum compound and/or a complex aluminum hydride.

The invention moreover relates to the use of such diarylphenoxyaluminum compounds as catalysts.

Moreover, the invention relates to a method of producing isopulegol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts.

The invention also relates to a method of producing menthol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts and subsequent hydrogenation.

An olefin polymerization process comprises gas-phase polymerization of at least one olefin monomer in more than one polymerization zones using a high activity Ziegler-Natta catalyst system comprising a solid, magnesium-supported, titanium-containing component and an aluminum alkyl component comprising introducing the titanium-containing component and an aluminum alkyl component into the first polymerization zone and then introducing additional aluminum alkyl component into a subsequent polymerization zone without added titanium-containing component.

The invention relates to a catalyst system used to prepare linear low density polyethylene by in situ copolymerization. The catalyst system is made up of oligomerization catalyst formed by homogeneous phase or loading type alpha-bi-imine pyridine iron series catalyst and aluminum alkyl-aluminoxane promoter, and copolymerization catalyst formed by titanium serious catalyst and alkyl aluminum or alkyl-aluminoxane promoter. The invention uses ethylene as the only monomer, makes it oligomerize to generate alpha-olefin, and process in situ copolymerization at the same time to prepare linear low density polyethylene in the same reactor which has the features of low melt pointing, low density, high mutual monomer inserting ratio, different length for side chain. And this method can simplify production technology, greatly reduce production cost.

The invention discloses a catalyst precursor and its preparation method, a catalyst and its application, and an ethylene polymerization method. The catalyst precursor is a bimetallic catalyst precursor which has an open structure shown as a formula I and is based on a salicylaldehyde imine ligand, the preparation method of the catalyst precursor is as follows: under complexation reaction conditions, contacting a compound having a structure shown as a formula IV with a compound with a molecular structure general formula of MCl4 (THF) 2 in an organic solvent; the catalyst provided by the invention comprises the catalyst precursor and alkyl aluminoxane; the invention also provides the application of the catalyst in olefin polymerization, the invention also provides the ethylene polymerization method which is as follows: under olefin polymerization conditions, in the presence of an organic solvent, contacting ethylene with the catalyst precursor and the alkyl aluminoxane for polymerization. The preparation method of the catalyst precursor is simple, and the catalyst is high in catalytic efficiency. The formula I and the formula IV are shown in the specification.

The present invention relates to the field of olefin polymerization, and discloses a catalyst system, which comprises a titanium-containing solid catalyst component, an alkyl aluminum compound and an external electron donor compound, wherein the titanium-containing solid catalyst component comprises at least two internal electron donor compounds such as a diol ester compound and a carboxylic acid ester, and the external electron donor compound is the combination of an ether ester compound and alkyl dialkoxysilane. The present invention further provides applications of the catalyst in olefin polymerization reactions. According to the present invention, when the solid catalyst component using the diol ester compound and the carboxylic acid ester as the internal electron donors is subjected to the olefin polymerization reaction, the compounding of the ether ester compound and the alkyl dialkoxysilane is added and used as the external electron donor used in the olefin polymerization reaction, such that the catalyst can maintain the high activity, and the melt index of the obtained polymer can be improved.

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.