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2586 results about "Cyclopentadiene" patented technology

Cyclopentadiene is an organic compound with the formula C₅H₆. This colorless liquid has a strong and unpleasant odor. At room temperature, this cyclic diene dimerizes over the course of hours to give dicyclopentadiene via a Diels–Alder reaction. This dimer can be restored by heating to give the monomer.

Dual metallocene catalysts for polymerization of bimodal polymers

This invention relates to catalyst compositions, methods, and polymers encompassing at least one first Group 4 metallocene compound comprising bridging η5-cyclopentadienyl-type ligands, in combination with at least one second Group 4 metallocene with non-bridging η5-cyclopentadienyl-type ligands, typically in combination with at least one cocatalyst, and at least one activator. The compositions and methods disclosed herein provide ethylene polymers with a bimodal molecular weight distribution.
Owner:CHEVRON PHILLIPS CHEMICAL CO LP

ALD of metal-containing films using cyclopentadienyl compounds

Atomic layer deposition (ALD) type processes for producing metal containing thin films comprise feeding into a reaction space vapor phase pulses of metal containing cyclopentadienyl precursors as a metal source material. In preferred embodiments the metal containing cyclopentadienyl reactant comprises a metal atom that is not directly bonded to an oxygen or halide atom. In other embodiments the metal atom is bonded to a cyclopentadienyl compound and separately bonded to at least one ligand via a nitrogen atom. In still other embodiments the metal containing cyclopentadienyl compound comprises a nitrogen-bridged ligand.
Owner:ASM IP HLDG BV

Aluminum-free monocyclopentadienyl metallocene catalysts for olefin polymerization

This invention relates to a catalyst system for the production of polyolefins comprising:(A) a Group IV B transition metal component represented by one of the two general formulaewherein(C5H5-y-xRx) is a cylopentadienyl ring(JR′z-l-y) is a heteroatom ligand in which J is an element with a coordination number of three from Group V-A or an element with a coordination number of two rom Group VI-A of the Periodic Table of Elements,each Q is independently, hydride, C1—C20 hydrocarbyl radicals, substituted hydrocarbyl radials wherein one or more hydrogen atoms is replaced by an electron withdrawing group, or C1—C20 hydrocarbyl-substituted metalloid radicals wherein the metalloid is selected from the group consisting of germanium and silicon, provided that Q is not a substituted or unsubstituted cyclopentadienyl ring, or both Q together may be an alkylidene, olefin, acetylene or a cyclometallated hydrocarbyl;“y” is 0 or 1; when “y” is 1, T is a covalent bridging group containing a Group IV-A or V-A element;L is a neutral Lewis base; and “w” is a number from 0 to 3;(B) an activator compound comprising (1) a cation; and (2) a compatible noncoordinating anion.
Owner:EXXONMOBIL CHEM PAT INC

High-melting polyolefin copolymer elastomers, catalysts and methods of synthesis

This invention relates to high melting polyolefin copolymers suitable as thermoplastic elastomers and catalysts and methods for their synthesis. These elastomeric olefin copolymers are characterized by a mole fraction of crystallizable component Xc from about 30 to about 99%; low glass transition temperatures, below -20° C., and typically below -50° C.; melting points above about 90° C.; high molecular weights; a molecular weight distribution MW / Mn< / =10; and a narrow composition distribution between chains of < / =15%. The novel copolymers of the invention range from reactor blends to multiblock copolymers that can be sequentially fractionated into fractions of differing crystallinities, which fractions nevertheless show compositions of comonomers which differ by less than 15% from the parent polymer (reactor product). The invention also relates to a process for producing such copolymers by utilizing an unbridged, substituted or unsubstituted cyclopentadienyl metallocene catalyst that is capable of interconverting between states with different copolymerization characteristics, which interconversion is controlled by selecting the substituents of the cyclopentadienyl ligands so that the rate of interconversion of the two states is within several orders of magnitude of the rate of formation of a single polymer chain. Where ri>rf the polymer can be characterized as multiblock; where ri<rf, the result is a polymer blend and where ri / rf is close to 1, the resulting polymer is a mixture of blend and multiblock. The metallocene catalysts of the invention are able to interconvert between more than two states, with embodiments of four states being shown in FIG. 2.
Owner:THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIV

High melting thermoplastic elastomeric alpha-olefin polymers (PRE/EPE effect) and catalysts therefor

InactiveUS6559262B1Activity of fluxional unbridged metallocene polymerization catalystsHigh molecular weightGroup 4/14 element organic compoundsMetallocenesElastomerEthylene Homopolymers
This invention relates generally to low ethylene insertions into I-olefin polymers and processes for production of such polymers using unbridged fluxional metallocenes, primarily substituted aryl indenyl metallocenes, and more particularly to use of unbridged, fluxional, cyclopentadienyl or indenyl metallocene catalyst systems in methods of production of high melting point I-olefin homo- and co-polymers, particularly elastomeric crystalline and amorphous block homo- and co-polymers of I-olefins. The activity of fluxional unbridged metallocene polymerization catalysts containing at least one 2-arylindene ligand is increased 10x or more by the addition of small (typically 0.1-10 wt. %) amounts of ethylene to the polymerization system, which increase is termed the Polymerization Rate-Enhancement effect (PRE), which is measured in terms of an Ethylene Enhancement Factor (EEF) as a dimensionless ratio in the range of from about 1.1 to about 10 or above. The amount of ethylene included in the reaction system can be selected and controlled to be so small as to result in essentially minimal (<2 mole %) incorporation of ethylene units into the resulting elastomeric polymer and the molecular weight may be increased. Amounts of ethylene to generate the PRE effect may be greater than 0.1 wt. % and preferably range up to about 2 wt. %. However, if a polymer with more ethylene is desired, additional ethylene may be incorporated into the polymerization feed, including up to 10 to about 50 mole % based on olefin units. A second important aspect of this invention is the ability to use a PRE activity-enhancing amount of ethylene in an olefin polymerization without substantially affecting the physical properties of the elastomer. In a third important aspect of this invention, I-olefin elastomers are produced through incorporation of ethylene using unbridged fluxional catalyst systems which may not otherwise produce acceptable elastomeric homopolymers. This effect is termed the EPE effect, for Elastomeric Property-Enhancing effect. The EPE amount of ethylene required to produce such elastomers typically overlaps the PRE activity-enhancing amount. Incorporation of up to about 5 mole % or more of ethylene typically will produce an elastomeric polymer using such catalyst systems. Typical useful amounts of incorporated ethylene include about 1 to 3 mole %. Preferred polymers of this invention retain sufficient crystallinity to provide a high melting point (by DSC) of about 80° C., preferably above 100° C., including in the range of from about 120° C. to about 140° C. and above. Novel flexible alpha-olefin homo and copolymers having elongation in excess of 600% and substantially no retained force are disclosed.
Owner:BP CORP NORTH AMERICA INC

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

Polymeric composites including dicyclopentadiene and related monomers

Compositions including fibers, fillers, reinforcing agents or other property-enhancing agents added to a polymeric matrix formed from DCPD monomer or related compounds such as norbornene and norbornadiene are disclosed. The composition has a mechanically forgiving matrix due to the polymer with the inherent strength and other physical properties of the enhancement agent according to the invention. Enhancement agents according to the invention generally include inorganic, organic and metallic substances in a variety of forms.
Owner:CYMETECH

High-melting polyolefin copolymer elastomers, catalysts and methods of synthesis

This invention relates to high melting polyolefin copolymers suitable as thermoplastic elastomers and catalysts and methods for their synthesis. These elastomeric olefin copolymers are characterized by a mole fraction of crystallizable component Xc from about 30 to about 99%; low glass transition temperatures, below -20° C., and typically below -50° C.; melting points above about 90° C.; high molecular weights; a molecular weight distribution MW / Mn< / =10; and a narrow composition distribution between chains of < / =15%. The novel copolymers of the invention range from reactor blends to multiblock copolymers that can be sequentially fractionated into fractions of differing crystallinities, which fractions nevertheless show compositions of comonomers which differ by less than 15% from the parent polymer (reactor product). The invention also relates to a process for producing such copolymers by utilizing an unbridged, substituted or unsubstituted cyclopentadienyl metallocene catalyst that is capable of interconverting between states with different copolymerization characteristics, which interconversion is controlled by selecting the substituents of the cyclopentadienyl ligands so that the rate of interconversion of the two states is within several orders of magnitude of the rate of formation of a single polymer chain. Where ri>rf the polymer can be characterized as multiblock; where ri<rf, the result is a polymer blend and where ri / rf is close to 1, the resulting polymer is a mixture of blend and multiblock. The metallocene catalysts of the invention are able to interconvert between more than two states, with embodiments of four states being shown in FIG. 2.
Owner:BP AMOCO CORP +1

Thermoplastic dicyclopentadiene-base open-ring polymers, hydrogenated derivatives thereof, and processes for the preparation of both

A thermoplastic dicyclopentadiene ring-opening polymer obtained by ring-opening polymerization of a monomer component containing a dicyclopentadiene monomer, characterized in that polycyclic rings which are repeating units of the polymer are bonded in cis-position relative to the carbon-carbon double bond of the main chain of the polymer in 50 mol % or more of the repeating units based on the total repeating units and the content of a low-molecular weight component of 2,000 or less in molecular weight is 10% by weight or less based on the total polymer components, and a hydrogenation product obtained by hydrogenating the carbon-carbon unsaturated bond of the thermoplastic dicyclopentadiene ring-opening polymer.
Owner:ZEON CORP

High temperature solution polymerization process with phosphinimine cyclopentadienyl metal (GRP IV) complex

This invention is a solution process for the preparation of high molecular weight ethylene copolymers comprising contacting olefin monomers, with a catalyst system at a polymerization temperature at or above about 80 DEG C. with a catalyst system comprising an unbridged Group 4 metal compound having a monocyclopentadienyl ligand, a phosphinimine ligand and at least one uninegative, activation reactive ligand. The process can be practiced at a reaction temperature of at least 80 DEG C. to obtain high number average molecular weight polymer.
Owner:NOVA CHEM (INT) SA

Method for the selective hydrogenation of polymer containing conjugated diene

InactiveUS6410657B1HalogenHydrogen atom
This invention relates to a method for the selective hydrogenation of the unsaturated double bonds in the conjugated diene units of a homopolymer or copolymer in the presence of a novel homogeneous organotitanium-based catalyst. Also, the process of this invention can demonstrate a high yield of hydrogenation and hydrogenation reproducibility using a novel catalyst, so prepared from a mixture consisting of a substituted or unsubstituted monocyclopentadienyl titanium compound expressed by the following formula 1 and lithium hydride derived from a reaction of both alkyl lithium and hydrogen in solution. In particular, this invention also relates to a novel method for the selective hydrogenation of unsaturated double bonds in the conjugated diene units of a conjugated diene polymer or copolymer, so prepared via the reaction between a conjugated diene monomer and vinyl-substituted aromatic monomerwherein, R1, R2, R3, R4 and R5, which may be same or different, are selected from hydrogen atoms and alkyl groups of 1~5 carbon atoms; X1, X2 and X3, which may be same or different, are selected from halogen atoms.
Owner:KOREA KUMHO PETROCHEMICAL CO LTD

Method of depositing rare earth oxide thin films

The present invention concerns a process for depositing rare earth oxide thin films, especially yttrium, lanthanum and gadolinium oxide thin films by an ALD process, according to which invention the source chemicals are cyclopentadienyl compounds of rare earth metals, especially those of yttrium, lanthanum and gadolinium. Suitable deposition temperatures for yttrium oxide are between 200 and 400° C. when the deposition pressure is between 1 and 50 mbar. Most suitable deposition temperatures for lanthanum oxide are between 160 and 165° C. when the deposition pressure is between 1 and 50 mbar.
Owner:ASM INTERNATIONAL

Metallocene compound, process for producing metallocene compound, olefin polymerization catalyst, process for producing polyolefin, and polyolefin

The metallocene compound according to the invention and the olefin polymerization catalyst containing the compound are intended to produce a catalyst capable of preparing an isotactic polymer with a high polymerization activity. The metallocene compound contains a substituted cyclopentadienyl group and a (substituted) fluorenyl group and has a structure wherein these groups are bridged by a hydrocarbon group or the like. The process for preparing a metallocene compound according to the invention is intended to selectively prepare a specific metallocene compound so as not to produce an isomer, and in this process an intermediate product is synthesized by a specific method. The process for preparing a polyolefin according to the invention is intended to prepare a polyolefin having excellent impact resistance and transparency, and this process comprises homopolymerizing an α-olefin of 3 to 8 carbon atoms or copolymerizing an olefin of 3 to 8 carbon atoms and another α-olefin in the presence of an olefin polymerization catalyst containing the above-mentioned metallocene compound.
Owner:MITSUI CHEM INC

Polymerization catalysts for producing high molecular weight polymers with low levels of long chain branching

This invention relates to catalyst compositions, methods, and polymers encompassing at least one Group 4 metallocene compound comprising bridging η5-cyclopentadienyl-type ligands, typically in combination with at least one cocatalyst, and at least one activator. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.
Owner:CHEVRON PHILLIPS CHEMICAL CO LP

Nonformaldehyde, nonfuming resorcinolic resins and methods of making and using the same

Methods for preparing formaldehyde-free resorcinol resins are disclosed. The methods generally comprise reacting resorcinol first with dicyclopentadiene and then reacting that mixture with an olefinic compound. The resins produced by this method are also disclosed, as are rubber compositions utilizing the present resins. The resins are characterized as having a free resorcinol content of about 1 wt. % or less, and yielding a suitable softening point when used in rubber applications.
Owner:SUMIKA ELECTRONICS MATERIALS INC USA D B A SUMITOMO CHEM ADVANCED TECH INC

Carbon and/or silicon bridged binuclear metallocene catalyst for styrene polymerization

An alkylene and / or silylene bridged binuclear metallocene catalyst for styrene polymerization is represented by the following formula (I): where M1 and M2 are the same or different transition metal of Group IVb of the Periodic Table; Cp1 and Cp2 are the same or different cyclopentadienyl; alkyl, alkoxy, silyl or halogen substituted cyclopentadienyl; indenyl; alkyl, alkoxy, silyl or halogen substituted indenyl; fluorenyl; or alkyl, alkoxy, silyl or halogen substituted fluorenyl, which is capable of pi -electron, eta 5-bonding with M1 or M2; each of E1, E2 and E3, independently of one another, is a carbon atom or a silicon atom; m, p and q are integers of 0 to 15 and m+p+q> / =1; each of R1, R2, R3, R4, R5 and R6, independently of one another, is a hydrogen, an alkyl, an aryl, an alkoxy or a halogen; X is a hydrogen, an alkyl, an alkoxy or a halogen; and n is 3. M1 and M2 may also be in cardin form by mixture of (I) with a compound which abstructs an X gray from each metal atom and substitution then with non-coordinating anions.
Owner:CHEIL IND INC

Production of multimodal polyethylene

InactiveUS6218472B1Polymer scienceSlurry
A process for the preparation of polyethylene resins having a multimodal molecular weight distribution which comprises:(i) contacting ethylene monomer and a comonomer comprising an alpha-olefin having from 3 to 10 carbon atoms with a first catalyst system in a first reactor under first polymerization conditions in a slurry process to produce a first polyethylene having a first molecular weight an HLMI of not more than 0.5 g / 10 min and a first density of not more than 0.925 g / ml and the first catalyst system comprising (a) a first metallocene catalyst of general formula R''(CpRm)(Cp'R'n)MQ2, wherein Cp is a cyclopentadienyl moiety, Cp' is a substituted or unsubstituted fluorenyl ring; each R is independently hydrogen or hydrocarbyl having 1 to 20 carbon atoms in which 0<=m<=4; each R' is independently hydrocarbyl having 1 to 20 carbon atoms in which 0<=n<=8, R'' is a bridge which comprises a C1-C20alkylene radical, a dialkyl germanium or silicon or siloxane, or an alkyl phosphine or amine radical, which bridge is substituted or unsubstituted, M is a Group IVB transition metal or vanadium and each Q is hydrocarbyl having 1 to 20 carbon atoms or halogen, the metallocene catalyst a centroid-M-centroid angle in the range 105° to 125°; and (b) a cocatalyst which activates the catalyst component;(ii) providing a second polyethylene having a second lower molecular weight and higher density than the first polyethylene; and(iii) mixing together the first and second polyethylenes to form a polyethylene resin having a multimodal molecular weight distribution.
Owner:FINA RES SA

Adhesive sheet for semiconductor connecting substrate, adhesive-backed tape for tab, adhesive-backed tape for wire-bonding connection, semiconductor connecting substrate, and semiconductor device

An adhesive sheet for a semiconductor connecting substrate consisting of a laminate having an adhesive layer on a substrate, wherein said adhesive layer contains a thermoplastic resin (A) and an epoxy resin (B) and said epoxy resin (B) contains at least one epoxy resin (B) selected from (I) dicyclopentadiene skeleton-containing epoxy resins, (II) terpene skeleton-containing epoxy resins, (III) biphenyl skeleton-containing epoxy resins and (IV) naphthalene skeleton-containing epoxy resins as an essential component; an adhesive-backed tape for TAB consisting of a laminate having an adhesive layer and a protective film layer on a flexible organic insulating film, wherein said adhesive layer has a softening temperature of 60 to 110° C. after having been cured and 50 hours or more in the insulation resistance dropping time after having been allowed to stand in an environment of 130° C. and 85% RH with DC 100 V applied; and a tape with adhesive for wire bonding connection consisting of a laminate having an adhesive layer and a protective film layer on a flexible organic insulating film, wherein said adhesive layer has a softening temperature of 120 to 170° C. after having been cured, a storage elastic modulus E' of 20 to 100 MPa at 150° C. and an insulation resistance dropping time of 50 hours or more after having been allowed to stand in an environment of 130° C. and 85% RH with DC 100 V applied. The adhesive sheet for a semiconductor connecting substrate, the adhesive-backed tape for TAB and the adhesive-backed tape for wire bonding connection of the present invention are excellent in adhesive strength, insulatability, dimensional accuracy, etc., and can improve the reliability of a semiconductor integrated circuit connecting substrate and a semiconductor device respectively for high density packaging.
Owner:TORAY IND INC

Polymerization catalysts and process for producing bimodal polymers in a single reactor

Catalyst compositions comprising a first metallocene compound, a second metallocene compound, an activator-support, and an organoaluminum compound are provided. An improved method for preparing cyclopentadienyl complexes used to produce polyolefins is also provided.
Owner:CHEVRON PHILLIPS CHEMICAL CO LP

Polyolefin production

A process for preparing polyolefins having a monomer length of up to C10, which comprises first contacting: (1) a metallocene catalyst component for the preparation of a polyolefin which comprises an isotactic polyolefin or syndiotactic / isotactic block polyolefin having a monomer length of up to C10, the component having the general formula:wherein Cp is a cyclopentadienyl ring substituted with at least one substituent of R1R2 and / or R3; Cp' is a substituted fluorenyl ring with substituents R1' and R2'; R'' is a structural bridge imparting stereorigidity to the component; R1 is a substituent on the cyclopentadienyl ring which is distal to the bridge; R2 is a substituent on the cyclopentadienyl ring which is proximal to the bridge and positioned either non-vicinal or vicinal to the distal substituent; R3 is a substituent on the cyclopentadienyl ring which is proximal to the bridge; R1' and R2' are each independently substituent groups on the fluorenyl ring; M is a Group IVB transition metal or vanadium; and each Q is hydrocarbyl, and (2) an aluminum- or boron-containing co-catalyst capable of activating the catalyst component. Second, contacting the activated catalyst with at least one olefin in a reaction zone under polymerization conditions to form an isotactic polyolefin or a syndiotactic / isotactic block polyolefin.
Owner:FINA RES SA

Metal Precursor Solutions For Chemical Vapor Deposition

Metal source containing precursor liquid solutions for chemical vapor deposition processes, including atomic layer deposition, for fabricating conformal metal-containing films on substrates are described. More specifically, the metal source precursor liquid solutions are comprised of (i) at least one metal complex selected from β-diketonates, β-ketoiminates, β-diiminates, alkyl metal, metal carbonyl, alkyl metal carbonyl, aryl metal, aryl metal carbonyl, cyclopentadienyl metal, cyclopentadienyl metal isonitrile, cyclopentadienyl metal nitrile, cyclopentadienyl metal carbonyl, metal alkoxide, metal ether alkoxide, and metal amides wherein the ligand can be monodentate, bidentate and multidentate coordinating to the metal atom and the metal is selected from group 2 to 14 elements, and (ii) a solvent selected from organic amides including linear amides and cyclic amides for such metal source containing precursors.
Owner:VERSUM MATERIALS US LLC

Polymerization process for olefin copolymers using bridged hafnocene compounds

The invention is a polymerization process for ethylene copolymers having a density less than 0.915 comprising contacting ethylene, one or more alpha-olefin monomer, and optionally one or more diene monomer, with a catalyst composition comprising the reaction product of at least one organometallic Group 4 metallocene compound derived from a bridged, fused-ring ligand containing biscyclopentadienyl hafnocene, said bridge being a substituted or unsubstituted carbon or silicon atom connecting the biscyclopentadienyl ligands, and a salt of a Group 13 element anionic complex having halogenated aromatic ligands in an essentially tetrahedral structure wherein the aromatic groups are polycyclic fused or pendant aromatic rings. The process is particularly suitable for the preparation of high comonomer content and high molecular weight ethylene-alpha-olefin plastomers and ethylene-propylene or ethylene-propylene-diene monomer elastomers.
Owner:EXXONMOBIL CHEM PAT INC

Class of volatile compounds for the deposition of thin films of metals and metal compounds

The invention provides an organometallic complex, containing oxygen free organic ligands, for the deposition of a metal, preferably copper, silver or gold, and preferably by way of chemical vapor deposition. The organometallic complex having the formula [(Do)nMLx]k where M is a metal preferably selected from the group consisting of Cu, Ag and Au; Do is selected from the group comprising ethers, phosphines, olefins, sulfides, pyridines, carbonyl, hydroxyl, cyclopentadiene, benzene derivatives, allyls, alkyls, amines, polyamines, aniline derivatives, cyclooctadiene and combinations thereof; n is an integer having a value from 0 to 4; k is an integer having a value from 1 to 4; x is an integer having a value from 1 to 4; and L is an amidinate ligand of the formula R1—NC(R2)N—R3 where R1, R2 and R3 are selected from the group consisting of alkyls, allyls, aryls, heteroaryls, hydrogen, non-metals and metalloids; and where R1, R2 and R3 are different or the same.
Owner:PRESIDENT & FELLOWS OF HARVARD COLLEGE
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