Abstract: A process for the preparation of linear olefins which comprises polymerizing ethylene in a hydrocarbon solvent at a temperature of 50.degree.-150.degree. C. in the presence of a catalyst comprising a zirconium metal compound, an organometallic compound wherein the metal is selected from the group consisting of zinc, magnesium and aluminum, and a basic salt of a carboxylic acid which forms a fine suspension or a homogeneous solution in the hydrocarbon solvent wherein the ratio of the salt equivalents to the moles of zirconium compound is from above 0 to about 4.0.
Abstract: Photodegradable and biodegradable polymers comprising both ketone functionality and hydrolyzable polymer ester or amide functionality and thermoplastic articles formed therefrom are disclosed.
Abstract: The present invention provides (1) curable liquid crystalline polyester monomers represented by the formula:R.sup.1 --A.sup.1 --B.sup.1 --A.sup.2 --B.sup.2 --A.sup.3 --R.sup.2where R.sup.1 and R.sup.2 are radicals selected from the group consisting of maleimide, substituted maleimide, nadimide, substituted naimide, ethynyl, and (C(R.sup.3).sub.2).sub.2 where R.sup.3 is hydrogen with the proviso that the two carbon atoms of (C(R.sup.3).sub.2).sub.2 are bound on the aromatic ring of A.sup.1 or A.sup.3 to adjacent carbon atoms, A.sup.1 and A.sup.3 are 1,4-phenylene and the same where said group contains one or more substituents selected from the group consisting of halo, e.g., fluoro, chloro, bromo, or iodo, nitro lower alkyl, e.g., methyl, ethyl, or propyl, alkoxy, e.g., methoxy, ethoxy, or propoxy, and fluoroalkyl, e.g., trifluoromethyl, pentafluoroethyl and the like, A.sup.
Type:
Grant
Filed:
January 22, 1991
Date of Patent:
May 19, 1992
Assignee:
The United States of America as represented by the Department of Energy
Abstract: The homopolymerization and copolymerization of ethene are carried out using a Ziegler catalyst system consisting of(1) a transition metal catalyst component,(2) an organoaluminum catalyst component and(3) an organohalogen catalyst component.In the homopolymerization or copolymerization, the solid-phase product (VI) used as (1) is the product which has been obtained by a method in which (1.1) first (1.1.1) an inorganic oxidic substance (I) as the carrier and (1.1.2) a solution (II) of (IIa) a certain oxahydrocarbon and (IIb) a vanadium trichloride/alcohol complex and (IIc) a silicon or boron compound are combined with formation of a suspension (III), the latter is evaporated down to form a solid-phase intermediate (IV), and (1.2) then (1.2.1) the intermediate (IV) obtained in (1.1) and (1.2.2) a dissolved organoaluminum compound (V) are combined with the formation of a suspension, the solid-phase product (VI) obtained as the suspended substance being the transition metal catalyst component (1).
Abstract: A method for producing a stereoregular polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, wherein a catalyst system is employed which comprises (i), (ii) and (iii): (A) a solid catalyst component obtained by reacting to a uniform solution containing (i) at least one member selected from the group consisting of metallic magnesium and an organic hydroxide compound and an oxygen-containing organic magnesium compound, (ii) a compound of Group IIIB of the Periodic Table, and (iii) an oxygen-containing organic silicon compound, (iv) at least one aluminum halide, to obtain a solid product, and reacting to the solid product, (v) an electron donative compound, and (vi) a titanium halide compound; (B) at least one member selected from the group consisting of organometallic compounds of metals of Groups IA, IIA, IIB, IIIB and IVB of the Periodic Table; and (C) an electron donative compound.
Abstract: Radiation curable compositions containing outstanding reactive diluents have been developed. The diluents are lower alkyl ether acrylates and methacrylates of particular alkoxylated and non-alkoxylated polyols.Examples are mono-methoxy trimethylolopropane diacrylate, mono-methoxy neopentyl glycol monoacrylate and mono-methoxy, ethoxylated neopentyl glycol monoacrylate having an average of about two moles of ethylene oxide.
Type:
Grant
Filed:
November 29, 1990
Date of Patent:
May 5, 1992
Assignee:
Diamond Shamrock Chemical Co.
Inventors:
Francis A. Higbie, Robert A. LieBerman, Ira M. Rose
Abstract: In the process according to the invention for the preparation of a polypropylene, a catalyst system is used which is based on the product of the reaction of a magnesium halide with an electron donor and a tetravalent titanium compound, a halogen-free organoaluminum compound and two different organosilicon compounds as stereo-regulator. Propylene homopolymers and copolymers having a very narrow molecular weight distribution and high isotacticity are obtained in high yields. The polymers are suitable, in particular, for injection molding.
Abstract: A method for activating supported chromium oxide catalysts in which a chromium-containing catalyst on a silica-containing base is first heated in an oxidizing atmosphere at temperatures up to about 850.degree. C. and then cooled down. During the cooling step of the catalyst, the oxidizing atmosphere is replaced by a non-oxidizing one, leading to an activated catalyst. A process for the polymerization of alpha-olefins, especially ethylene, in which at least one alpha-olefin is contacted, under polymerization conditions, with the catalyst activated by the method described above.
Abstract: Stereoregular polymers having a molecular weight distribution of less than 5.0 and an isotactic index in excess of 96 percent are produced by polymerizing an alpha-olefin having 3 to 8 carbon atoms in a low pressure gas phase fluid bed process at a temperature in excess of 80.degree. C. employing a heat stable catalyst system comprising (a) a solid catalyst component containing magnesium, titanium, halide and a polycarboxylic acid ester containing two coplanar ester groups attached to adjacent carbon atoms, as inside electron donor, (b) an organoaluminum cocatalyst, and (c) a silicon compound containing a silicon-oxygen-carbon linkage, as outside electron donor.
Type:
Grant
Filed:
May 19, 1987
Date of Patent:
March 3, 1992
Assignee:
Union Carbide Chemicals & Plastics Technology Corporation
Inventors:
Robert C. Brady, III, Francis G. Stakem, Han T. Liu, Allen Noshay
Abstract: A method for producing a homopolymer or copolymer of an .alpha.-olefin is disclosed, wherein a specific catalyst is used, said catalyst comprising a solid catalyst component obtained by contacting, in the presence of a chlorinated hydrocarbon solvent, a titanium compound and an aromatic carboxylic ester with a solid component obtained by reacting a hydrocarbon solvent-soluble organomagnesium compound having an alkoxy group with a specified chlorosilane compound having an Si--H bond; an organoaluminum compound; and an alkoxysilane compound. By the method of the present invention, an .alpha.-olefin homopolymer or copolymer exhibiting high bulk density and stereoregularity can be efficiently produced under even such polymerization reaction conditions, that the polymerization temperature is high and the polymerization time is long.
Abstract: The invention relates to polymers and oligomers characterized in that they have been prepared from .alpha.-olefin monomers or mixtures thereof and the distances between the methyl branching paints are controllable by the selection of the .alpha.-olefins and to a process for preparing said novel polymers and oligomers.
Abstract: An improved process for producing an ethylene copolymer composed of a major proportion of ethylene and a minor proportion of an alpha-olefin having 3 to 10 carbon atoms and having a density of 0.910 to 0.945 g/cm.sup.3 and an ethylene content of 85 to 99.5 mole %. The use of a titanium catalyst component (A) which meets a parametric combination of specific requirements is essential in this process. The process can industrially advantageously give a low to medium density ethylene copolymer of high quality with high productivity while advantageously circumventing the operational troubles which have been difficult to avoid by conventional processes.
Abstract: A process and a catalyst for the production of elastomeric primarily isotactic polyolefins characterized by short average block lengths wherein olefins are polymerized in the presence of the catalyst which comprises the reaction product of a magnesium alkoxide and a tetravalent titanium halide which takes place in the presence of an electron donor, an organoaluminum compound, and a selectivity control agent which is an effectively hindered heterocyclic aromatic nitrogen compound wherein the hinderance is provided by a chloro or a methoxy group.
Abstract: A novel process for production of polyethylene comprises polymerizing ethylene or a mixture of ethylene and a copolymerizable comonomer in the presence of a Ziegler-type catalyst at a pressure of 200 atm or more and at a temperature of 125.degree. C. or more, wherein an organic peroxide is added to the resulting polymerization product taken out of a reaction zone to deactivate the remaining catalyst. Formation of undesired oligomers or low-molecular polymers is prevented because the reaction does not proceed in the polymerization product taken out of the reaction zone. There is almost no retardation of the polymerization reaction even by the recycled use of the monomer separated and collected from the polymerization product.
Type:
Grant
Filed:
June 22, 1987
Date of Patent:
February 4, 1992
Assignee:
Mitsubishi Petrochemical Company Limited
Abstract: The invention relates to a process for the preparation of a predominantly crystalline ethylene/propylene copolymer having less than 15 mol % of propylene units, which can be carried out in liquid propylene as the suspending agent, if metallocene catalyst components of the formulae I, II or III are employed and the partial pressures of ethylene and propylene have a specific ratio. ##STR1## By means of this process, it is possible to increase the possible uses of polymerization plants which work with liquid propylene.
Type:
Grant
Filed:
October 19, 1989
Date of Patent:
February 4, 1992
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Martin Antberg, Walter Spaleck, Jurgen Rohrmann, Hartmut Luker, Andreas Winter
Abstract: Crystalline copolymers of ethylene and alpha-olefins CH.sub.2 .dbd.CHR in which R is an alkyl group having 2 to 8 carbon atoms, containing 0.5 to 3% by moles of polymerized alpha-olefin and having a density lower than 0.945 g/cc are obtained by polymerizing, in the gas phase, mixtures of ethylene and the alpha-olefins in contact with catalysts prepared from (1) Ti compounds supported on Mg halides and (2) organometallic compounds, which are active in the polymerization of ethylene but exhibit little, if any, activity in the homo- or copolymerization of the alpha-olefins.
Abstract: A process for polymerizing or copolymerizing ethylene, either alone or in combination with other olefins, comprising contacting said ethylene or alpha-olefin, either alone or in combination with other olefins, with a catalyst comprising a cyclopentadienyl-transition metal compound and an alumoxane compound at an elevated temperature and pressure and wherein the ratio of aluminum in the alumoxane to the total metal in the metallocene is in the range of 1000:1 to 0.5:1.
Type:
Grant
Filed:
September 10, 1987
Date of Patent:
January 28, 1992
Assignee:
Exxon Chemical Patents, Inc.
Inventors:
Howard C. Welborn, Jr., Charles S. Speed
Abstract: An ethylene-.alpha.-olefin copolymer is disclosed, which comprises ethylene and an .alpha.-olefin having from 3 to 10 carbon atoms, has an ethylene/.alpha.-olefin molar ratio of from 88/12 to 98/2, and which has a number average molecular weight of from 35,000 to 80,000 and a weight average molecular weight/number average molecular weight ratio of from 1.8/1 to 3.0/1 as determined by gel permeation chromatography. A process for producing the ethylene-.alpha.-olefin copolymer is also disclosed. The ethylene-.alpha.-olefin copolymer exhibits excellent transparency and excellent low-temperature heat-sealing properties. The process is advantageous from the standpoint of equipment, energy and cost.
Abstract: The present invention relates to a process for the start up of polymerization or copolymerization in the gas phase by bringing the said alpha-olefins in contact under polymerization or copolymerization conditions in a fluidized bed and/or with mechanical stirring with a charge powder, in the presence of a catalyst system of the Ziegler-Natta type, this process being characterized in that the charge powder used is previously dehydrated and subjected to a treatment by bringing the said charge powder into contact with an organoaluminum compound for a period of at least five minutes, so that the polymerization or copolymerization starts up immediately after the contracting of the alpha-olefins with the charge powder in the presence of the catalyst system.
Type:
Grant
Filed:
April 12, 1991
Date of Patent:
December 31, 1991
Assignee:
BP Chemicals Limited
Inventors:
Daniel C. Durand, Frederic R. M. M. Morterol, Stylianos Sandis
Abstract: An olefin polymerization supported catalyst comprising the supported reaction product of at least one metallocene of a metal of Group IVB, VB, and VIB of the Periodic Table, a non-metallocene transition metal containing compound of a Group IBV, VB, or VIB metal and an alumoxane, said reaction product formed in the presence of the support. The supported product is highly useful for the polymerization of olefins especially ethylene and especially for the copolymerization of ethylene and other mono and diolefins.