Abstract:
A method for the delivery of a catalyst to a polymerization reactor is disclosed, comprising: contacting a catalyst with a carrier fluid comprising an inert hydrocarbon in gaseous form, the inert hydrocarbon having a normal boiling point of about -1°C to about 81°C; and flowing the carrier fluid to the polymerization reactor such that the carrier fluid transports the catalyst to the polymerization reactor. A catalyst delivery system is disclosed, comprising: a catalyst vessel for containing a catalyst; a catalyst injection line for delivering the catalyst to a polymerization reactor, the catalyst injection line being in fluid communication with the catalyst vessel and the polymerization reactor; and a carrier fluid line in fluid communication with the catalyst injection line for delivering a carrier fluid comprising an inert hydrocarbon to the catalyst injection line, the inert hydrocarbon having a normal boiling point of about -1°C to about 81°C.
Abstract:
Catalyst systems and methods for making and using the same are provided. The catalyst system can include a catalyst compound having (1) at least one cyclopentadienyl ligand and at least one heteroatom ligand; (2) two non-bridged cyclopentadienyl ligands; or (3) two or more heteroatom ligands. The catalyst system further comprise a support comprising fluorinated silica. The support may be essentially free of alumina. The catalyst system further comprises an aluminoxane, preferably methylaluminoxane, modified methylaluminoxane, or a combination thereof.
Abstract:
A process for polymerizing olefin(s) utilizing a cyclic bridged metallocene catalyst system to produce polymers with improved properties is provided. The catalyst system may include a cyclic bridged metallocene, LA(R'SiR')L B ZrQ 2 , activated by an activator, the activator comprising aluminoxane, a modified aluminoxane, or a mixture thereof, and supported by a support, where: L A and L B are independently an unsubstituted or a substituted cyclopentadienyl ligand bonded to Zr and defined by the formula (C 5 H 4 - d R d ), where R is hydrogen, a hydrocarbyl substituent, a substituted hydrocarbyl substituent, or a heteroatom substituent, and where d is O, 1, 2, 3 or 4; L A and L B are connected to one another with a cyclic silicon bridge, R' SiR', where R' are independently hydrocarbyl or substituted hydrocarbyl substituents that are connected with each other to form a silacycle ring; and each Q is a labile hydrocarbyl or a substituted hydrocarbyl ligand.
Abstract:
Catalyst systems and methods for making and using the same. A method for making a catalyst support includes forming a mixture of a support material and a fluoride donor. The mixture is added to a fluidized bed reactor. The mixture is fluidized to form a fluidized bed while maintaining a ratio of a pressure drop across a distributor plate to a pressure drop across the fluidized bed of greater than about 7 %. The mixture is calcined to decompose the fluoride donor, forming a fluorinated support.
Abstract:
Catalyst systems and methods for making and using the same. A method of polymerizing olefins to produce a polyolefin polymer with a multimodal composition distribution, includes contacting ethylene and a comonomer with a catalyst system. The catalyst system includes a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system. The first catalyst compound includes a compound with the general formula (C 5 H a R 1 b )(C 5 H c R 2 d )HfX 2 . The second catalyst compound comprises the following formula: (A), wherein each R 3 or R 4 is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R 3 or R 4 may be the same or different, and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R 3 group.
Abstract:
Provided is a method for making a polyolefin comprising contacting one or more olefins in a reactor containing a catalyst; polymerizing the one or more olefins to produce an olefin polymer characterized by a first melt flow ratio (MFR) and a first haze; and altering the reaction temperature in the reactor to shift the first MFR to a MFR that is different than the first MFR and to shift the first haze to a haze that is different than the first haze.
Abstract:
The invention relates to a method for evaluating the condition of a fluidized bed reactor by examining the condition of the reactor wall. Specifically, the invention relates to a method for measuring static in the reactor using a static probe that is located at the distributor plate and comprises a distributor plate cap. The invention also relates to methods of determining a static level using a radio frequency (rf). The static measurements are provided to indicate or predict major continuity disturbances in the fluidized bed gas phase reactor.
Abstract:
Catalyst systems and methods for making and using the same. A method for making a catalyst support includes forming a mixture of a support material and a fluoride donor. The mixture is added to a fluidized bed reactor. The mixture is fluidized to form a fluidized bed while maintaining a flow rate of a fluidizing gas of about 0.1 ft. / sec at less than about 370 °C and greater than about 0.35 ft./ sec at temperatures greater than about 370 °C. The mixture is calcined to decompose the fluoride donor, forming a fluorinated support.
Abstract:
Polymers, and systems and methods for making and using the same are described herein. A polymer includes ethylene and at least one alpha olefin having from 4 to 20 carbon atoms. The polymer is formed by a trimmed catalyst system including a supported catalyst including bis(n-propylcyclopentadienyl) hafnium (R 1 )(R 2 ) and a trim catalyst comprising meso-O(SiMe 2 lnd) 2 Zr 2 (R 1 )(R 2 ), wherein R 1 and R 2 are each, independently, methyl, chloro, fluoro, or a hydrocarbyl group.