摘要:
Polymerization reactor systems providing real-time control of the average particle size of catalyst system components are disclosed. Methods for operating such polymerization reactor systems also are described.
摘要:
Polymerization reactor systems providing real-time control of the average particle size of catalyst system components are disclosed. Methods for operating such polymerization reactor systems also are described.
摘要:
A disengagement vessel employing a lock hopper effectively reduces concentration of non-polymer-associated components in the polymer product slurry of a first olefin slurry polymerization reactor, allowing cascading of a second slurry polymerization reactor operating at lesser concentration of comonomers, hydrogen, and other components to produce multicompositional polyolefin polymers and/or polymers having a multimodal monomer distribution, e.g. diblock polymers having substantially non-overlapping comonomer contents between the blocks.
摘要:
A method for making ethylene polymers and copolymers is disclosed. The method uses a catalyst system comprising a low level of an aluminum-containing activator, a bridged indenoindolyl transition metal complex, and a treated silica support. The method enables economical preparation of ethylene copolymers having very low density. The silica-supported, bridged complexes incorporate comonomers efficiently and are valuable for a commercial slurry loop process. Use of a bridged indeno[2,1-b]indolyl complex provides exceptionally efficient comonomer incorporation, and gives polymers with a substantial and controlled level of long-chain branching. The method facilitates the production of a wide variety of polyolefins, from HDPE to plastomers.
摘要:
A gas-phase process for polymerizing an olefin is disclosed. The process involves feeding the catalyst into the reactor in a stream of gas that comprises at least 75 volume % of a noble gas in order to reduce static.
摘要:
A process for the gas phase polymerization of olefins. In this process a transition metal-containing solid catalyst component is introduced into a cylindrical section of a vertically disposed reactor in a first stream. A second stream, comprising an organometallic cocatalyst component is simultaneously separately introduced into the said cylindrical section of a vertically disposed reactor at a distance from the point of introduction of the first stream of no more than about 20% of the inside diameter of the tubular reactor.
摘要:
Embodiments of the present application provide a method for manufacturing a polyolefin and a system for implementing the method. The method comprises combining a catalyst with a diluent mixture containing a diluent and an olefin monomer in a polymerization reactor. The diluent may comprise propane, butane, or isobutane, or a combination thereof. The polymerization reactor is operated at a pressure above a critical pressure of the diluent, but below the critical temperature of the diluent.
摘要:
Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a triple-decker bimetallic complex. The complex includes two Group 3-10 transition metals and a delocalized dianionic ligand that is pi-bonded to each of the metals. The behavior of the catalysts can be modified by choice of each metal, by the choice of the dianionic ligand, or by choice of the ancillary ligands. The invention provides a new way to make a large variety of catalyst systems.
摘要:
Processes of forming polyolefins are described herein. One or more specific embodiments of the processes generally include introducing olefin monomer selected from C2-C3 olefins into a first reaction zone under first polymerization conditions to form a first polyolefin; withdrawing a transfer effluent from the first reaction zone, the transfer effluent including first polyolefin and unreacted olefin monomer; introducing the transfer effluent, a comonomer selected from C4-C8 olefins, and additional olefin monomer to a second reaction zone under second polymerization conditions to form a second reactor product; maintaining an essentially constant comonomer:olefin monomer ratio in the second reaction zone; and withdrawing at least a portion of the second reactor product, wherein the second reactor product includes a bimodal polyolefin.
摘要:
Embodiments of the present application provide a method for manufacturing a polyolefin and a system for implementing the method. The method comprises combining a catalyst with a diluent mixture containing a diluent and an olefin monomer in a polymerization reactor. The diluent may comprise propane, butane, or isobutane, or a combination thereof. The polymerization reactor is operated at a pressure above a critical pressure of the diluent, but below the critical temperature of the diluent.