Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

70 results about "Non-coordinating anion" patented technology

Anions that interact weakly with cations are termed non-coordinating anions, although a more accurate term is weakly coordinating anion. Non-coordinating anions are useful in studying the reactivity of electrophilic cations. They are commonly found as counterions for cationic metal complexes with an unsaturated coordination sphere. These special anions are essential components of homogeneous olefin polymerisation catalysts, where the active catalyst is a coordinatively unsaturated, cationic transition metal complex. For example, they are employed as counterions for the 14 valence electron cations [(C₅H₅)₂ZrR]⁺ (R = methyl or a growing polyethylene chain). Complexes derived from non-coordinating anions have been used to catalyze hydrogenation, hydrosilylation, oligomerization, and the living polymerization of olefins. The popularization of non-coordinating anions has contributed to increased understanding of agostic complexes wherein hydrocarbons and hydrogen serve as ligands. Non-coordinating anions are important components of many superacids, which result from the combination of Brønsted acids and Lewis acids.

Process to produce low viscosity poly-alpha-olefins

This invention relates to a process to produce a polyalpha-olefin comprising: 1) contacting one or more alpha-olefin monomers having 3 to 24 carbon atoms with an unbridged substituted bis cyclopentadienyl transition metal compound having: 1) at least one non-isoolefin substitution on both cyclopentadientyl rings, or 2) at least two substitutions on at least one cyclopentadienyl ring, a non-coordinating anion activator, and optionally an alkyl-aluminum compound, where the molar ratio of transition metal compound to activator is 10:1 to 0.1:1, and if the alkyl aluminum compound is present then the molar ratio of alkyl aluminum compound to transition metal compound is 1:4 to 4000:1, under polymerization conditions wherein: i) hydrogen is present at a partial pressure of 0.1 to 50 psi, based upon the total pressure of the reactor or the concentration of the hydrogen is from 1 to 10,000 ppm or less by weight; ii) wherein the alpha-olefin monomer(s) having 3 to 24 carbon atoms are present at 10 volume % or more based upon the total volume of the catalyst/activator/alkylaluminum compound solutions, monomers, and any diluents or solvents present in the reaction; iii) the residence time of the reaction is at least 5 minutes; iv) the productivity of the process is at least 43,000 grams of total product per gram of transition metal compound; v) the process is continuous or semi-continuous, and vi) the temperature in the reaction zone does not rise by more than 10° C. during the reaction; and vii) ethylene is not present at more than 30 volume % of the monomers entering the reaction zone; and 2) obtaining a polyalpha-olefin (PAO), optionally hydrogenating the PAO, wherein the PAO comprises at least 50 mole % of a C3 to C24 alpha-olefin monomer, and wherein the PAO has a kinematic viscosity at 100° C. of 20 cSt or less.
Owner:EXXONMOBIL CHEM PAT INC

Process To Produce Polyalphaolefins

The present invention relates to processes to produce liquid poly-alpha-olefins comprising:a) contacting in a reaction zone, in the presence of from 0 to 60 psi hydrogen, one or more C3 to C20 alpha-olefin monomers with a non-coordinating anion activator, a single bridged meso-metallocene transition metal compound having less than about 35 wt % racemic isomer, and a co-activator selected from the group consisting of alkyl aluminum compounds and alkyl alumoxanes, provided that when the alkyl alumoxane is present it is present in a molar ratio of less than 0.1:1 of alkylalumoxane to meso-metallocene, and provided that when the alkyl aluminum compound is present it is present at a molar ratio of alkyl aluminum to meso-metallocene of from 2:1 to 10,000 to 1, where the molar ratio of activator to meso-metallocene is from 10:1 to 0.1:1, andprovided that ethylene is not present at more than 30 volume % of the monomers entering the reaction zone, and provided that the alpha-olefin monomers in the feed components are present in at least 20 wt % or more based upon the weight of the meso-metallocene, non-coordinating anion activator, co-activator, monomers, and solvent or diluent, andwhere: i) the productivity of the process is at least 50,000 g of total product per gram of transition metal compound (where the total product is defined to be the total amount of product exiting the reactor, minus unreacted monomers and solvents); and ii) no more than 5% monomer is converted from olefin to alkane; andb) obtaining a liquid polyalphaolefin product having a pour point of less than 25° C., a KV100 of 2 to 6000 cSt, 20 weight percent dimer or less and a viscosity index of 60 or more.
Owner:EXXONMOBIL CHEM PAT INC

High temperature olefin polymerization process

The invention is directed to olefin polymerization processes using bridged hafnocene catalyst complexes comprising highly substituted noncoordinating anions that are surprisingly stable under high temperature olefin polymerization processes such that olefin copolymers having significant amount of incorporated comonomer can be prepared with high molecular weights. More specifically, the invention is a polymerization process for ethylene copolymers having a melt index of about 0.87 to about 0.930 comprising contacting, under homogeneous polymerization conditions at a reaction temperature at or above 140° C. to 225° C., ethylene and one or more comonomers capable of insertion polymerization with a bridged hafnocene catalyst complex derived from A) a biscyclopentadienyl hafnium organometallic compound having i) at least one unsubstituted cyclopentadienyl ligand or aromatic fused-ring substituted cyclopentadienyl ligand, ii) one aromatic fused-ring substituted cyclopentadienyl ligand, iii) and a covalent bridge connecting the two cyclopentadienyl ligands, said bridge comprising a single carbon or silicon atom; and B) an activating cocatalyst, precursor ionic compound comprising a halogenated tetraaryl-substituted Group 13 anion wherein each aryl substituent contains at least two cyclic aromatic rings.
Owner:EXXONMOBIL CHEM PAT INC

Catalyst system and process for olefin polymerization

The present application relates to a new catalyst system for the polymerization of olefins, comprising a new ionic activator having the formula: [R<1>R<2>R<3>AH]<+>[Y]<->, wherein [Y]<-> is a non-coordinating anion (NCA), A is nitrogen or phosphorus, R<1> and R<2> are hydrocarbyl groups or heteroatom-containing hydrocarbyl groups and together form a first, 3- to 10-membered non-aromatic ring with A, wherein any number of adjacent ring members may optionally be members of at least one second, aromatic or aliphatic ring or aliphatic and / or aromatic ring system of two or more rings, wherein said at least one second ring or ring system is fused to said first ring, and wherein any atom of the first and / or at least one second ring or ring system is a carbon atom or a heteroatom and may be substituted independently by one or more substituents selected from the group consisting of a hydrogen atom, halogen atom C1 to C10 alkyl, C5 to C15 aryl, C6 to C25 arylalkyl, and C6 to C25 alkylaryl, and R<3> is a hydrogen atom or C1 to C10 alkyl, or R<3> is a C1 to C10 alkylene group that connects to said first ring and / or to said at least one second ring or ring system. The present application also relates to a process for the polymerization of olefins, preferably propylene, using this and other catalyst systems, as well as to polymers made by said process.
Owner:EXXONMOBIL CHEM PAT INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products