Process for producing polyolefin granular resins with increased settled bulk density

Abstract

A process for increasing the settled bulk density of a granular polyolefin polymer includes: feeding a catalyst stream to a gas-phase polymerization reactor, the catalyst stream comprising catalyst particles, optionally in slurry form, by suspension in mineral oil and / or other hydrocarbon liquid contained in a carrier fluid; feeding a support gas to the gas-phase polymerization reactor along with the catalyst stream entering the reactor, the support gas being fed to the gas-phase reactor at a rate; forming polyolefin particles in the gas-phase polymerization reactor by contacting the catalyst particles with a monomer, and optionally one or more comonomers; determining a settled bulk density of the granular polyolefin particles; and, based on the settled bulk density, selectively increasing or decreasing the rate of the support gas to maintain the settled bulk density above a preset limit.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 231,007, filed August 9, 2021, which is incorporated by reference in its entirety for all purposes. [Background technology]

[0002] Polyolefin polymers are used in many different applications and fields. Polyolefin polymers are, for example, thermoplastic polymers that can be easily processed. Polyolefin polymers can also be recycled and reused. Polyolefin polymers are formed from abundantly available hydrocarbons, such as ethylene, propylene and other alpha-olefins, obtained from petrochemicals and other sources.

[0003] Polypropylene, a type of polyolefin polymer, generally has a linear structure based on propylene monomer. Polypropylene can have a variety of different stereospecific configurations. Polypropylene can be, for example, isotactic, syndiotactic, and atactic. Isotactic polypropylene is perhaps the most common form and can be highly crystalline. Polypropylene products that can be produced include polypropylene copolymers, including homopolymers, modified polypropylene polymers, and polypropylene terpolymers. By modifying polypropylene or copolymerizing propylene with other monomers, a variety of different polymer products can be produced with desired properties for specific applications.

[0004] One type of process for producing polyolefin polymers is typically referred to as gas phase polymerization. During a typical gas phase polymerization, one or more monomers are contacted with a catalyst to form a bed of polymer particles maintained in a fluidized state by a fluidization medium. A typical gas phase polymerization reactor includes a vessel containing a fluidized bed, a distribution plate, and a product discharge system. The catalyst can be fed into the polymerization reactor and contacted with the olefin monomers that form part of the fluidization medium.

[0005] When producing polyolefin polymers in gas phase polymerization processes, those skilled in the art have attempted to produce polymer resins composed of granular polymer particles having a relatively high settled bulk density (SBD). Increasing the settled bulk density can facilitate easier handling of the polymer resin and greatly increase the efficiency of the particle discharge system. These benefits are also seen downstream from the reactor when feeding the polymer resin to the feed hopper of the extruder. Increasing the settled bulk density can eliminate bottlenecks in the solids flow rate through particle discharge systems, extruder hoppers, rotary feeders, etc., and therefore increase the overall production rate of the polymer process.

[0006] However, there is a problem in determining the process parameters that affect the settled bulk density.Therefore, there is currently a need for a process for producing granular polyolefin polymers with increased settled bulk density.In particular, there is a need for a process for increasing the settled bulk density of granular polyolefin polymers during production that can be integrated into all different types of polyolefin production processes that use different catalysts and produce different products. Summary of the Invention

[0007] Generally, the present disclosure is directed to a process and system for producing polyolefin polymer resins. The process of the present disclosure is generally carried out in a gas phase reactor. According to the present disclosure, various process parameters are controlled to optimize and / or maximize the settled bulk density of the granular polyolefin particles formed.

[0008] In one embodiment, for example, the disclosure is directed to a process for increasing the settled bulk density of a polyolefin polymer resin. The process includes feeding a catalyst stream to a gas phase reactor. The catalyst stream includes catalyst particles contained in a carrier fluid. The catalyst particles can include a Ziegler-Natta catalyst or a metallocene catalyst. A support gas is fed to the gas phase reactor through a support tube coaxial with the catalyst stream entering the reactor. The support gas is fed to the gas phase reactor at a rate.

[0009] Polyolefin particles are formed by contacting catalyst particles with monomer and optionally one or more comonomers in a gas phase reactor. The settled bulk density of the granular polyolefin particles is determined by ASTM D1895. According to the present disclosure, based on the determined settled bulk density of the granular polymer produced, the velocity of the supporting gas is selectively increased or decreased to maintain the settled bulk density above a preset level.

[0010] In one embodiment, the catalyst flow enters the gas phase reactor through a catalyst inlet having a cross-sectional area, and the support gas flows into the gas phase reactor through a gas feed inlet having a cross-sectional area in the range of 0.25 to 4.0 times that of the catalyst inlet. For example, in one embodiment, the support gas inlet can be concentric with the catalyst inlet and / or the catalyst flow. For example, the catalyst flow can be distributed into the gas phase reactor through a nozzle surrounded by the support gas inlet.

[0011] The supporting gas flowing to the gas phase reactor may include a monomer gas, an inert gas, or a mixture thereof. In one embodiment, the supporting gas includes only an inert gas. Alternatively, the supporting gas may include propylene gas.

[0012] The catalyst stream may include a suspension containing catalyst particles combined with a carrier fluid. The suspension may be made of catalyst particles combined with an oil, such as mineral oil. The carrier fluid may be an inert gas, such as nitrogen gas, in one embodiment. In an alternative embodiment, the carrier fluid may be liquid propylene.

[0013] The velocity of the supporting gas entering the gas phase reactor can vary widely, depending on various factors such as the catalyst flow and the components contained in the supporting gas flow, as well as various other factors. In one embodiment, the velocity of the supporting gas can range from about 30 m / s to about 200 m / s, e.g., from about 50 m / s to about 150 m / s. In various embodiments, a gas phase reactor can be operated at a velocity of about 250 kg / m using the processes of the present disclosure. 3 For example, about 350 kg / m 3 For example, about 380 kg / m 3 The settled bulk density can be maintained at a preset level greater than about 600 kg / m. 3 is less than.

[0014] The process of the present disclosure can be used to increase the settled bulk density of polyolefin resins when using either Ziegler-Natta or metallocene catalysts, or even a mixture of Ziegler-Natta and metallocene catalysts. For example, in one embodiment, the catalyst system includes a Ziegler-Natta solid catalyst, an external electron donor including a selectivity control agent (SCA), and optionally an activity limiting agent (ALA). The solid catalyst can include a magnesium moiety, a titanium moiety, and an internal electron donor. In one aspect, the internal electron donor is a substituted phenylene diester or phthalate compound. In one aspect, the solid catalyst component can further include an organosilicon compound and an epoxy compound.

[0015] Alternatively, the catalyst system may comprise a metallocene catalyst. The metallocene catalyst is (C5R x ) y R'z (C5R m )MQ n-y-1 may include.

[0016] In the above formula, M is a metal from group III to VIII of the periodic table of elements, (C5R x ) and (C5R m ) are the same or different cyclopentadienyl or substituted cyclopentadienyl groups bonded to M, R are the same or different and are hydrogen or a hydrocarbyl group such as an alkyl, alkenyl, aryl, alkylaryl, or arylalkyl group containing 1 to 20 carbon atoms, or two carbon atoms joined together to form a C4-C6 ring, R' is a C1-C4 substituted or unsubstituted alkylene group, a dialkyl or diaryl germanium or silicon, or two (C5R x ) and (C5R m ) is an alkyl or aryl phosphine or amine group bridging the rings, Q is a hydrocarbyl group such as an aryl, alkyl, alkenyl, alkylaryl, or arylalkyl group having 1 to 20 carbon atoms, a hydrocarboxy group having 1 to 20 carbon atoms, or a halogen, which may be the same or different from each other, z is 0 or 1, y is 0, 1, or 2, and when y is 0, z is 0, n is 0, 1, 2, 3, or 4 depending on the valence state of M, and ny≧1.

[0017] The process and system of the present disclosure may include a controller for implementing the process. The controller may be any suitable programmable device, such as, for example, one or more microprocessors. In one embodiment, the determined settled bulk density of the polyolefin resin may be communicated to the controller, and the controller may be configured to control the rate of the supporting gas supplied to the gas-phase reactor based on the determined settled bulk density to maintain the settled bulk density above a preset limit. In one embodiment, the controller may operate in an open feed loop. Alternatively, the controller may operate in a closed feed loop.

[0018] Other features and aspects of the disclosure are discussed in more detail below. [Brief description of the drawings]

[0019] A full and enabling disclosure is more particularly set forth in the remainder of the specification, including reference to the accompanying drawings, in which: [Figure 1] FIG. 1 is a schematic diagram of one embodiment of a gas phase polymerization process according to the present disclosure. [Diagram 2] 1 is a cross-sectional view of a catalyst injection device that may be used in accordance with the present disclosure.

[0020] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Those skilled in the art will appreciate that this discussion is a description of exemplary embodiments only, and is not intended to limit the broader aspects of the disclosure.

[0022] In general, the present disclosure is directed to a process and system for optimizing and / or maximizing the settled bulk density of polyolefin resins during the production of the resins. The polyolefin resins are formed by contacting a catalyst with a monomer and optionally one or more comonomers to form polyolefin particles. The formed particulate polyolefins can be polypropylene homopolymers, polypropylene copolymers, polyethylene homopolymers, polyethylene copolymers, and the like. Increasing the settled bulk density of the polymer particles formed according to the present disclosure facilitates handling of the polymer resins, resulting in greater throughput and process efficiency.

[0023] The present disclosure is generally directed to manipulating various variables in the gas phase polymerization process used to produce polyolefin polymers. Through the process of the present disclosure, the settled bulk density can be increased and maximized, thereby increasing the efficiency of the reactor polymer discharge system and other units downstream of the reactor, such as product purge bins and rotary valves. Higher settled bulk density also facilitates the conveying of product to the extruder and the feeding of polymer resin to the extruder to produce polymer pellets or articles.

[0024] During the gas phase polymerization process, catalyst particles contained in a carrier fluid are injected into a fluidized bed reactor. Typically, the catalyst particles are mixed with an oil, such as mineral oil, to form a slurry, which is then combined with the carrier fluid. The carrier fluid can be, for example, liquid propylene, or an inert gas, such as nitrogen gas. The catalyst inlet in the reactor may be surrounded by a coaxial support tube that supplies the support gas to the gas phase reactor along with the catalyst flow. The support gas is designed to help disperse the catalyst particles and allow them to better penetrate into the reactor, preventing localized concentrations of fresh catalyst that can cause localized hot areas or spots in the reactor.

[0025] According to the present disclosure, the velocity of the support gas, where it contacts the catalyst flow, is controlled to maximize or increase the settled bulk density. It has been discovered that the velocity of the support gas can significantly affect the settled bulk density, but the selection of the velocity or range of velocities for any particular polymerization process may depend on different factors. For example, the ability to increase settled bulk density by adjusting the velocity of the support gas is catalyst dependent. In other words, the velocity of the support gas can be adjusted based on the particular catalyst used during the polymerization. However, understanding the relationship between the support gas velocity and the catalyst also makes the process robust in that the process of the present disclosure can be used to increase settled bulk density when producing any type of polyolefin polymer, using any particular type of catalyst, whether the catalyst is a Ziegler-Natta catalyst or a metallocene catalyst.

[0026] It is believed that the velocity of the support gas is related to the attrition of the catalyst particles, which in turn affects the polyolefin particle formation and thus the particle morphology, including the settled bulk density. Polymerization of the monomer occurs at the active sites on the catalyst particles. A single catalyst particle may contain a large amount of active sites. Polyolefin polymers are formed at the active sites on the catalyst particles to form particulates. These particulates then aggregate to form granular polyolefin particles. This is the so-called "multigrain model of polymer growth" (see Hutchinson et al., Journal of Applied Polymer Science, Vol. 44, pp 1389-1414 (1992)). Ideally, the particulates formed on the catalyst support continue to grow until no intraparticle voids remain between adjacent particulates, resulting in void-free granular particles, but completely void-free granular particles have not been achieved by any commercial gas-phase polymerization process. It has been found that reducing the intraparticle voids increases the bulk density and improves the handling properties of the resulting resin.

[0027] In one embodiment of the present disclosure, the velocity of the supporting gas in the gas phase process is used to control the attrition of the catalyst to reduce the catalyst particle size. For example, reducing the catalyst particle size can form polymer particles with less voids and therefore higher settling bulk density. For example, reducing the catalyst particle size creates more heat transfer surface of the particle, which helps to reduce the local temperature around each active site on the catalyst. In addition, the heat generated by each catalyst particle is also reduced. It is believed that if the polymer particulate growing on the active site is cooled sufficiently or remains at a relatively low temperature, the particulate continues to grow until it reaches the adjacent particulate, which can dramatically reduce the intra-particle voids. On the other hand, if the active site is hot enough, the catalytic activity of the active site may kinetically decrease and stop, so that the particulate growing on the active site stops growing, thus leaving voids between the adjacent particulates. Thus, if the catalyst particle size is relatively large, there is less surface area available for heat transfer, and more heat is generated in each particle, which can lead to a relatively high temperature around the active site, which can stop the polymer growth. If the polymer particles at each active site cease to expand, the resulting polymer particles may have larger void spaces. As a result, for some catalyst particles, increasing the velocity of the support gas can reduce the catalyst particle size through attrition and therefore increase the settled bulk density.

[0028] However, other catalyst particles are more prone to wear away and form particles with irregular shapes. Irregularly shaped catalyst particles contain active sites in non-uniform locations. Thus, the polymer fines formed at the active sites do not grow together uniformly as would occur if the catalyst particles were more spherical. This can worsen heat transfer from the particles to the bed and promote relatively high temperatures at some active sites. As a result, irregularly shaped catalyst particles can cause larger voids and thus reduce the settled bulk density. In addition, the final granular polymer product also has a reduced settled bulk density when it has an irregular particle shape, because the "packing" of the irregularly shaped particles leaves more interparticle voids between the particles.

[0029] As a result, as discussed above, the velocity of the supporting gas can be adjusted and controlled based on the type of catalyst particles involved in the process. In certain embodiments, a relatively high gas velocity may be desirable. However, in other embodiments, a relatively low gas velocity may be preferred.

[0030] As mentioned above, the system and process of the present disclosure are particularly applicable to gas-phase polymerization processes. As used herein, typically, "gas-phase polymerization" is the passage of an ascending fluidization medium (containing one or more monomers) in the presence of a catalyst through a fluidized bed of polymer particles maintained in a fluidized state by the fluidization medium. "Fluidization", "fluidized", or "fluidizing" is a gas-solid contact process in which a bed of fine polymer particles is lifted and agitated by an upward flow of fluid. Fluidization occurs in a bed of particulate matter when the upward flow of fluid through the interstices of the bed of particles acquires a pressure differential and an increase in frictional resistance that exceeds the weight of the particulate matter, i.e., the particles are suspended by the fluid rather than being immobile. Thus, a "fluidized bed" is a plurality of polymer particles suspended in a fluidized state by the flow of the fluidization medium. The "fluidizing medium" typically contains one or more olefin monomers, hydrogen (as a chain terminator for the polymerization reaction), inert gases (e.g., N2 and saturated hydrocarbons), and optionally liquids (e.g., condensed hydrocarbons in the form of discrete droplets), which rise through a gas-phase reactor.

[0031] The reactor itself may be any gas phase reactor known in the art. In a preferred embodiment, the reactor is a fluidized bed reactor as shown in Figure 1. The reactor may also be arranged horizontally or vertically or in other configurations as is commonly known in the art.

[0032] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present disclosure and without diminishing its intended advantages. Accordingly, such changes and modifications are intended to be covered by the appended claims.

[0033] A typical gas phase polymerization reactor includes a vessel (i.e., reactor), a fluidized bed, a distribution plate, inlet and outlet piping, a compressor, a cycle gas cooler or heat exchanger, and a product discharge system. The vessel includes a reaction zone and a velocity reduction zone, each of which is located above the distribution plate. The fluidized bed is located in the reaction zone. In one embodiment, the fluidizing medium includes propylene gas and other gases such as hydrogen or nitrogen, and optionally other olefins having carbon numbers from 2 or 4 to 10.

[0034] The catalyst is typically fed to the bottom of the reactor. Upon contact of the catalyst with the fluidizing medium, a reaction occurs and polymer particles grow. The fluidizing medium passes upward through the fluidized bed, providing a medium for heat transfer and fluidization. The reactor includes an expansion section located above the reaction section. In the expansion section, the velocity of the fluidizing medium decreases. Particles with a terminal velocity higher than that of the fluidizing medium separate from the fluidizing medium flow and return to the dense fluidized bed by gravity. Some fine particles may be carried out of the reactor by the fluidizing medium because their terminal velocity is smaller than the gas velocity. Thus, the expansion section has the function of decreasing the fluidizing medium velocity, which can promote the return of the polymer particles to the dense fluidized bed and minimize the amount of fine particles exiting the reactor. After exiting the reactor, the fluidizing medium passes through a compressor and one or more heat exchangers to remove the heat of polymerization before being reintroduced into the reaction section of the reactor through a distribution plate. The fluidizing medium may or may not contain a certain amount of liquid after cooling and condensation.

[0035] One or more olefin monomers can be introduced into the gas phase reactor to react with the catalyst to form a polymer in the form of granular polymer particles. Non-limiting examples of suitable olefin monomers include ethylene, propylene, C 4~20 α-Olefins, e.g., C 4~12 α-olefins, such as 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, etc.; C 4~20Diolefins, such as 1,3-butadiene, 1,3-pentadiene, norbornadiene, 5-ethylidene-2-norbornene (ENB), and dicyclopentadiene; C including styrene, o-methylstyrene, m-methylstyrene, and p-methylstyrene, divinylbenzene, vinylbiphenyl, vinylnaphthalene 8~20 Vinyl aromatic compounds; and halogen-substituted C 8~40 Vinyl aromatic compounds include, for example, chlorostyrenes and fluorostyrenes.

[0036] 1 and 2, for illustrative purposes only, one embodiment of a gas phase polymerization process is shown. As shown in Figure 1, the system includes a gas phase reactor 10 that includes a reaction zone 12 and a velocity reduction zone 14. In one exemplary embodiment, the height to diameter ratio of the reaction zone can vary from about 2:1 to about 7:1.

[0037] The reaction zone 12 contains a bed of growing and grown polymer particles, polymerizable monomers, and other gaseous components (including hydrogen and inert gases) in the form of a fluidization medium that flows through the reaction zone. The superficial gas velocity (SGV) of the fluidization medium (which is typically in a gaseous state in the majority of the reactor) is sufficient to produce a fluidized bed. For example, the superficial gas velocity in the reaction zone 12 may be from about 0.1 ft / s to about 6 ft / s. The superficial gas velocity may be, for example, greater than about 0.2 ft / s, for example, greater than about 0.4 ft / s, for example, greater than about 0.7 ft / s, and typically less than about 3.0 ft / s. The superficial gas velocity is greater than the minimum fluidization velocity of the particle bed. For example, the superficial gas velocity may be greater than 1.5 times the minimum fluidization velocity, for example, greater than 2.5 times, for example, greater than 4 times.

[0038] Make-up fluidization medium (e.g., fresh polyolefin monomer to replace that consumed during polymerization) is generally fed to the process at point 18, or other location in the cycle loop, such as upstream of compressor 30, and combined with recycle line 22. The composition of the recycle stream is typically measured by a gas analyzer 21. The superficial gas velocity in reactor 10 can be adjusted by adjusting the flow rate of the fluidization medium through compressor 30. Gas analyzer 21 can be positioned to test the recycled gas at a point between compressor 30 and heat exchanger 24, as shown in FIG. 1.

[0039] The fluidizing medium contained in the recycle stream 22 is fed to the reactor 10 toward the bottom at a point 26 below the bed. The reactor 10 may contain a gas distribution plate 28 to help uniformly fluidize the bed and to support the solid particles contained in the fluidized bed prior to start-up or when the system is shut down. The fluidizing medium passing upwardly through and exiting the bed removes the heat of reaction generated by the exothermic polymerization reaction.

[0040] As shown in Figure 1, the fluidization medium flows through the reactor 10 into the velocity reduction zone 14. Within the velocity reduction zone 14, most of the particles fall back into the dense fluidized bed in the reaction zone 12, while a small amount of fine particles are carried by the fluidization medium out of the reactor into a cyclic loop.

[0041] The recycled fluidizing medium is compressed in a compressor 30 and passed through a heat exchanger 24 to remove the polymerization reaction heat absorbed by the fluidizing medium as it passes through the reactor before it is returned to the reactor 10. In one embodiment, the reactor 10 may include a fluid flow deflector 32 located at the inlet to the reactor, which helps to better distribute the fluidizing medium in the space below the distribution plate 28, prevents the contained polymer particles from settling and agglomerating into solid masses, and maintains and entrains or re-entrains any particles or liquid that may have settled or become separated. The distribution plate 28 then allows the fluidizing medium to enter the fluidized bed in the reaction zone 12 with a uniform velocity and a uniform amount of entrained fine particles and optionally a uniform amount of condensed liquid over the entire cross-sectional area of ​​the reactor.

[0042] The granular polyolefin polymer resin produced by the reaction is discharged from the reactor 10 through line 44. As mentioned above, maintaining the settled bulk density of the polymer particles above a preset limit facilitates the handling and transport of the polymer particles. For example, a relatively high settled bulk density allows for a relatively high "drainage efficiency", which means that a smaller amount of fluid is discharged together with the polymer particles. These discharged fluids need to be further processed (e.g., returned to the reactor) for economic and safety reasons. Also, a smaller amount of discharged fluids can reduce interruptions to the operation of the reactor. Therefore, a relatively small amount of discharged fluids is desirable.

[0043] The polymerization catalyst enters reactor 10 through nozzle 42 through line 48. Nozzle 42 is shown in more detail in FIG.

[0044] Catalyst stream 48 includes catalyst particles, optionally a suspension such as mineral oil or a liquid alkane, and a carrier fluid. The catalyst particles (e.g., in the form of a slurry by being suspended in mineral oil) and carrier fluid are injected into reactor 10 through nozzle 42. On a volumetric basis, catalyst stream 48 contains primarily carrier fluid. For example, the carrier fluid occupies more than 50% of the volume of catalyst stream 48, such as more than 60%, e.g., more than 70%.

[0045] The carrier fluid in catalyst stream 48 may include a monomer, a comonomer, an inert hydrocarbon, an inert gas, or a mixture thereof. In one embodiment, for example, the carrier fluid is a liquid monomer, such as liquid propylene. When liquid propylene is used as the carrier fluid, the flow rate of catalyst stream 48 is typically greater than about 15 kg / h, such as greater than about 25 kg / h, such as greater than about 35 kg / h. When liquid propylene is used as the carrier fluid, the flow rate of catalyst stream 48 is typically less than about 250 kg / h, such as less than about 210 kg / h.

[0046] Alternatively, the carrier fluid may be an inert gas, such as nitrogen gas. When nitrogen gas is the carrier fluid, the flow rate of catalyst stream 48 may be generally greater than about 3 kg / h, such as greater than about 5 kg / h, such as greater than about 7 kg / h, and generally less than about 55 kg / h, such as less than about 45 kg / h, such as less than about 35 kg / h.

[0047] In addition to catalyst flow 48, as shown in Figure 1, the system further includes a support gas flow 47. Support gas flow 47 is separated from catalyst flow 48 until it is discharged into reactor 10. In one embodiment, for example, support gas flow 47 is fed into gas-phase reactor 10 through nozzle 42 such that the support gas is discharged at the tip of the tube very close to the tip of the catalyst injection tube. Typically, the support gas flows within a support tube that is positioned coaxially with the catalyst injection tube.

[0048] The support gas stream may generally include a monomer, a comonomer, an inert hydrocarbon, an inert gas, or a mixture thereof. In one embodiment, for example, the support gas may include a monomer gas, such as an olefin gas. In one particular embodiment, for example, the support gas may be vaporized propylene. In general, the flow rate of the support gas is greater than about 40 kg / h, such as greater than about 50 kg / h, such as greater than about 60 kg / h. The flow rate of the support gas is generally less than about 600 kg / h, such as less than about 550 kg / h, such as less than about 500 kg / h. In one aspect, the flow rate is greater than about 410 kg / h, such as greater than about 430 kg / h, and less than about 700 kg / h. The above flow rates are particularly relevant when vaporized propylene is used as the support gas.

[0049] 2, nozzle 42 for injecting catalyst stream 48 and supporting gas stream 47 into polymerization reactor 10 is shown in more detail. As shown, catalyst stream 48, in one embodiment, enters central channel 70. Channel 70 defines a cross-sectional area. Support gas stream 47 enters nozzle 42 and enters annular channel 72. In one embodiment, channel 72 has a cross-sectional area that is about 0.25-4.0 times the cross-sectional area of ​​central channel 70 (based on inside diameter). In one embodiment, for example, channel 72 is concentric with central channel 70.

[0050] As discussed above, when catalyst flow 48 and supporting gas flow 47 are injected into reactor 10, it has been found that supporting gas flow 47 has an effect on catalyst attrition that is catalyst dependent. More specifically, in accordance with the present disclosure, the velocity of fluidizing gas flow 47 at the outlet of nozzle 42 can be controlled and adjusted to control and adjust the polymer resin formation, which can ultimately affect the settled bulk density of the particles formed.

[0051] The velocity of the support gas at the outlet of the nozzle 42 can vary widely depending on the particular application and the results desired. For example, the velocity of the support gas stream 47 can be adjusted and controlled based on the feed system and catalyst particles present in the reactor, and the desired settled bulk density to be obtained.

[0052] In general, the velocity of the support gas flow 47 may be anywhere from about 5.4 m / s to about 81 m / s, including all 1 m / s increments therebetween. For example, the support gas velocity may be greater than about 5.4 m / s, such as greater than about 6.8 m / s, such as greater than about 8.1 m / s. In many embodiments, the velocity of the support gas flow 47 is less than about 81 m / s, such as less than about 75 m / s, such as less than about 68 m / s. The temperature of the support gas flow 47 may also be a factor in determining the velocity. The support gas flow 47 may be anywhere from about 23° C. to about 150° C., for example. For example, when the support gas flow 47 contains vaporized propylene, the temperature of the support gas flow 47 may be from about 100° C. to about 150° C., such as from about 120° C. to about 130° C.

[0053] Referring again to FIG. 1, the system of the present disclosure may also include a controller 80. The controller 80 may be any suitable programmable or logic device. The controller 80 may be, for example, one or more microprocessors. As shown in FIG. 1, the controller 80 is in communication with the polymer discharge line 44 and the feed gas flow 47. For example, the controller 80 may receive a settled bulk density measurement of the polymer resin formed in the reactor 10 and, based on the settled bulk density, adjust the velocity of the support gas flow 47 to maintain the settled bulk density of the polymer resin above a preset limit. For example, in certain embodiments, depending on the polymer being produced and the catalyst being used, the settled bulk density preset limit may be about 250 kg / m 3 Larger, e.g., about 300 kg / m 3 Larger, e.g., about 350 kg / m 3 Larger, e.g., about 400 kg / m 3 The settled bulk density is generally up to about 600 kg / m for most of the polyolefin powders. 3 is less than.

[0054] The controller 80 may operate in an open loop mode, as shown in Figure 1, or in a closed loop mode. In an open loop mode, a user may provide an input to adjust the rate of the supporting gas flow 47. In a closed loop system, the controller 80 may automatically adjust the rate of the supporting gas flow 47 based on a stable bulk density measurement. The settled bulk density of granular polymer powders is typically measured according to ASTM D1895.

[0055] As discussed above, the velocity of the supporting gas flow exiting nozzle 42 is catalyst dependent in optimizing or maximizing settled bulk density. Of particular advantage, the processes and systems of the present disclosure can be used to optimize settled bulk density of polymer resins produced using either Ziegler-Natta or metallocene catalysts, or mixtures thereof.

[0056] In one embodiment, the catalyst composition is a Ziegler-Natta catalyst composition. As used herein, a "Ziegler-Natta catalyst composition" is a combination of (1) a transition metal compound of an element of Groups IV to VIII of the Periodic Table (procatalyst) and (2) an organometallic compound of a metal of Groups I to III of the Periodic Table (cocatalyst). These components of the catalyst can be added together or separately to the reactor. A non-limiting example of a gas phase polymerization reactor is one in which the procatalyst and cocatalyst are fed separately to the reactor, i.e., only the procatalyst passes through nozzle 42 in FIG. 2. Non-limiting examples of suitable Ziegler-Natta procatalysts include oxyhalides of titanium, vanadium, chromium, molybdenum, and zirconium. Non-limiting examples of Ziegler-Natta cocatalysts include hydrides, alkyls, or aryls of aluminum, lithium, zinc, tin, cadmium, beryllium, and magnesium.

[0057] Generally, Ziegler-Natta catalysts have different attrition characteristics than metallocene catalysts. In one aspect, Ziegler-Natta catalysts may be more susceptible to attrition. Thus, for some Ziegler-Natta catalysts, typically a relatively low support gas flow rate may be used to increase the settled bulk density in certain applications.

[0058] All different types of Ziegler-Natta catalysts can be used in the disclosed method. The Ziegler-Natta catalyst comprises a solid catalyst component. The solid catalyst component can comprise (i) magnesium, (ii) a transition metal compound of an element of Groups IV-VIII of the Periodic Table, (iii) a halide, oxyhalide, and / or alkoxide of (i) and / or (ii), and (iv) a combination of (i), (ii), and (iii). Non-limiting examples of suitable catalyst components include halides, oxyhalides, and alkoxides of magnesium, manganese, titanium, vanadium, chromium, molybdenum, zirconium, hafnium, and combinations thereof.

[0059] In one embodiment, the preparation of the catalyst component involves halogenation of mixed magnesium and titanium alkoxides.

[0060] In various embodiments, the catalyst component is a magnesium moiety compound (MagMo), a mixed magnesium titanium compound (MagTi), or a benzoic acid-containing magnesium chloride compound (BenMag). In one embodiment, the catalyst precursor is a magnesium moiety ("MagMo") precursor. The MagMo precursor comprises a magnesium moiety. Non-limiting examples of suitable magnesium moieties include anhydrous magnesium chloride and / or its alcohol adducts, magnesium alkoxides or aryloxides, mixed magnesium alkoxyhalides, and / or carboxylated magnesium dialkoxides or aryloxides. In one embodiment, the MagMo precursor is magnesium di(C 1~4 ) alkoxide. In a further embodiment, the MagMo precursor is diethoxymagnesium.

[0061] In another embodiment, the catalyst component is a mixed magnesium / titanium compound ("MagTi"). A "MagTi precursor" is a compound of the formula Mg d Ti(OR e )fX g wherein R eis an aliphatic or aromatic hydrocarbon group having 1 to 14 carbon atoms or COR′, or R′ is an aliphatic or aromatic hydrocarbon group having 1 to 14 carbon atoms, and each OR e The groups are the same or different, X is independently chlorine, bromine or iodine, preferably chlorine, d is 0.5 to 56, or 2 to 4, f is 2 to 116, or 5 to 15, and g is 0.5 to 116, or 1 to 3. The precursor is prepared by controlled precipitation, removing alcohol from the reaction mixture used in its preparation. In one embodiment, the reaction medium comprises a mixture of an aromatic liquid, especially a chlorinated aromatic compound, most especially chlorobenzene, and an alkanol, especially ethanol. Suitable halogenating agents include titanium tetrabromide, titanium tetrachloride or titanium trichloride, especially titanium tetrachloride. Removal of the alkanol from the solution used for halogenation precipitates a solid precursor, which has a particularly desirable shape and surface area. Furthermore, the precursor obtained is generally particularly uniform in particle size.

[0062] In another embodiment, the catalyst precursor is a benzoic acid-containing magnesium chloride material ("BenMag"). As used herein, "benzoic acid-containing magnesium chloride" ("BenMag") can be a catalyst containing a benzoic acid internal electron donor (i.e., a halogenated catalyst component). The BenMag material can also include a titanium moiety, such as a titanium halide. The benzoic acid internal donor is unstable and can be replaced by other electron donors during catalyst and / or catalyst synthesis. Non-limiting examples of suitable benzoic acid groups include ethyl benzoate, methyl benzoate, ethyl p-methoxybenzoate, methyl p-ethoxybenzoate, ethyl p-ethoxybenzoate, ethyl p-chlorobenzoate. In one embodiment, the benzoic acid group is ethyl benzoate. In one embodiment, the BenMag catalyst component can be the product of halogenation of any catalyst component (i.e., MagMo precursor or MagTi precursor) in the presence of a benzoic acid compound.

[0063] In another embodiment, the solid catalyst component can be formed from a magnesium moiety, a titanium moiety, an epoxy compound, an organosilicon compound, and an internal electron donor. In one embodiment, an organophosphorus compound can also be incorporated into the solid catalyst component. For example, in one embodiment, a halide-containing magnesium compound can be dissolved in a mixture including an epoxy compound, an organophosphorus compound, and a hydrocarbon solvent. The resulting solution can be treated with a titanium compound in the presence of an organosilicon compound, and optionally with an internal electron donor to form a solid precipitate. The solid precipitate can then be treated with an additional amount of titanium compound. The titanium compound used to form the catalyst can have the following chemical formula: Ti(OR) g X 4-g wherein each R is independently a C1-C4 alkyl, X is Br, Cl, or I, and g is 0, 1, 2, 3, or 4.

[0064] In some embodiments, the organosilicon is a monomeric or polymeric compound. The organosilicon compound may contain -Si-O-Si- groups in one molecule or between other molecules. Other illustrative examples of organosilicon compounds include polydialkylsiloxanes and / or tetraalkoxysilanes. Such compounds may be used alone or in combination. The organosilicon compound may be used in combination with an aluminum alkoxide and an internal electron donor.

[0065] The aluminum alkoxides referred to above may have the formula Al(OR')3, where each R' is individually a hydrocarbon having up to 20 carbon atoms. This may include where each R' is individually methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, and the like.

[0066] Examples of halide-containing magnesium compounds include magnesium chloride, magnesium bromide, magnesium iodide, and magnesium fluoride. In one embodiment, the halide-containing magnesium compound is magnesium chloride.

[0067] Examples of epoxy compounds include, but are not limited to, glycidyl-containing compounds of the following formula:

[0068] [ka] where "a" is 1, 2, 3, 4, or 5; X is F, Cl, Br, I, or methyl; R a is H, alkyl, aryl, or cyclyl. In one embodiment, the alkyl epoxide is epichlorohydrin. In some embodiments, the epoxy compound is a haloalkyl epoxide or a non-haloalkyl epoxide.

[0069] According to some embodiments, the epoxy compound is selected from the group consisting of ethylene oxide, propylene oxide, 1,2-epoxybutane, 2,3-epoxybutane, 1,2-epoxyhexane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,2-epoxydodecane, 1,2-epoxytetradecane, 1,2-epoxyhexadecane, 1,2-epoxyoctadecane, 7,8-epoxy-2-methyloctadecane, 2-vinyloxirane, 2-methyl-2-vinyloxirane, 1,2 -Epoxy-5-hexene;1,2-Epoxy-7-octene;1-Phenyl-2,3-epoxypropane;1-(1-Naphthyl)-2,3-epoxypropane;1-Cyclohexyl-3,4-epoxybutane;1,3-Butadiene dioxide;1,2,7,8-Diepoxyoctane;Cyclopentene oxide;Cyclooctene oxide;α-Pinene oxide;2,3-Epoxynorbornane;Limonene oxide;Cyclodecane epoxide;2,3,5,6-Diepoxynorbornane Lunan;Styrene oxide;3-Methylstyrene oxide;1,2-Epoxybutylbenzene;1,2-Epoxyoctylbenzene;Stilbene oxide;3-Vinylstyrene oxide;1-(1-methyl-1,2-epoxyethyl)-3-(1-methylvinylbenzene);1,4-Bis(1,2-epoxypropyl)benzene;1,3-Bis(1,2-epoxy-1-methylethyl)benzene;1,4-Bis(1,2-epoxy-1-methylethyl)benzene;Epifluoro hydrin;epichlorohydrin;epibromohydrin;hexafluoropropylene oxide;1,2-epoxy-4-fluorobutane;1-(2,3-epoxypropyl)-4-fluorobenzene;1-(3,4-epoxybutyl)-2-fluorobenzene;1-(2,3-epoxypropyl)-4-chlorobenzene;1-(3,4-epoxybutyl)-3-chlorobenzene;4-fluoro-1,2-cyclohexene oxide;6-chloro-2,3-epoxybicyclo[2.2.1]heptane;4-Fluorostyrene oxide;1-(1,2-epoxypropyl)-3-trifluorobenzene;3-Acetyl-1,2-epoxypropane;4-Benzoyl-1,2-epoxybutane;4-(4-benzoyl)phenyl-1,2-epoxybutane;4,4'-Bis(3,4-epoxybutyl)benzophenone;3,4-Epoxy-1-cyclohexanone;2,3-Epoxy-5-oxobicyclo[2.2.1]heptane;3-Acetylstyrene oxide;4-(1,2-epoxypropyl)benzophenone;Glycidyl methyl ether ether;Butyl glycidyl ether;2-Ethylhexyl glycidyl ether;Allyl glycidyl ether;Ethyl 3,4-epoxybutyl ether;Glycidyl phenyl ether;Glycidyl 4-tert-butylphenyl ether;Glycidyl 4-chlorophenyl ether;Glycidyl 4-methoxyphenyl ether;Glycidyl 2-phenylphenyl ether;Glycidyl 1-naphthyl ether;Glycidyl 2-phenylphenyl ether;Glycidyl 1-naphthyl ether;Glycidyl 4-indolyl ether;Glycidyl N-methyl-α- Quinolone-4-yl ether;Ethylene glycol diglycidyl ether;1,4-Butanediol diglycidyl ether;1,2-Diglycidyloxybenzene;2,2-Bis(4-glycidyloxyphenyl)propane;Tris(4-glycidyloxyphenyl)methane;Poly(oxypropylene)triol triglycidyl ether;Glycidyl ether of phenol novolac;1,2-Epoxy-4-methoxycyclohexane;2,3-Epoxy-5,6-dimethoxybicyclo[2.2.1]heptane;4-Methoxystyrene oxide; 1-(1,2-epoxybutyl)-2-phenoxybenzene;Glycidyl formate;Glycidyl acetate;2,3-epoxybutyl acetate;Glycidyl butyrate;Glycidyl benzoate;Diglycidyl terephthalate;Poly(glycidyl acrylate);Poly(glycidyl methacrylate);Copolymers of glycidyl acrylate with other monomers;Copolymers of glycidyl methacrylate with other monomers;1,2-epoxy-4-methoxycarbonylcyclohexane;2,3-epoxy-5-butoxycarbonylbicyclo[2.2.1]Heptane;Ethyl 4-(1,2-epoxyethyl)benzoate;Methyl 3-(1,2-epoxybutyl)benzoate;Methyl 3-(1,2-epoxybutyl)-5-phenylbenzoate;N,N-Glycidyl-methylacetamide;N,N-Ethylglycidylpropionamide;N,N-Glycidylmethylbenzamide;N-(4,5-epoxypentyl)-N-methyl-benzamide;N,N-Diglycylaniline;Bis(4-diglycidylaminophenyl)methane;Poly(N,N-glycidylmethylacrylamide) );1,2-epoxy-3-(diphenylcarbamoyl)cyclohexane;2,3-epoxy-6-(dimethylcarbamoyl)bicyclo[2.2.1]heptane;2-(dimethylcarbamoyl)styrene oxide;4-(1,2-epoxybutyl)-4'-(dimethylcarbamoyl)biphenyl;4-cyano-1,2-epoxybutane;1-(3-cyanophenyl)-2,3-epoxybutane;2-cyanostyrene oxide;and 6-cyano-1-(1,2-epoxy-2-phenylethyl)naphthalene.

[0070] An example of an organophosphorus compound that can be used is a phosphate ester, such as a trialkyl phosphate ester. Such a compound can be represented by the following formula:

[0071] [ka] In the formula, R1, R2, and R3 are each independently methyl, ethyl, and straight or branched chain (C3 to C 10 ) alkyl groups. In one embodiment, the trialkyl phosphate is tributyl phosphate.

[0072] In yet another embodiment, the substantially spherical MgCl2-nEtOH adduct may be formed by a spray crystallization process. In this process, MgCl2-nROH melt (n is 1-6) is sprayed into a vessel at a temperature of 20-80 °C while introducing an inert gas into the top of the vessel. The molten droplets are transferred to a crystallization zone where an inert gas is introduced at a temperature of -50-20 °C, causing the molten droplets to crystallize into spherical, non-agglomerated solid particles. The spherical MgCl2 particles are then classified into desired sizes. Particles of undesired sizes can be recycled. In a preferred embodiment for catalyst synthesis, the spherical MgCl2 precursor has an average particle size (Malvern d) of about 8-150 microns, preferably 10-100 microns, and most preferably 10-30 microns, between the mean particle size. 50 ).

[0073] The catalyst components can be converted to solid catalysts by halogenation. Halogenation involves contacting the catalyst components with a halogenating agent in the presence of an internal electron donor. Halogenation converts the magnesium moieties present in the catalyst components to magnesium halide supports on which titanium moieties (such as titanium halides) are deposited. Without wishing to be bound by any particular theory, it is believed that during halogenation, the internal electron donor (1) adjusts the location of titanium on the magnesium-based support, (2) promotes the conversion of the magnesium and titanium moieties to their respective halides, and (3) adjusts the crystal size of the magnesium halide support during the conversion. Thus, the provision of an internal electron donor results in a catalyst composition with improved stereoselectivity.

[0074] In one embodiment, the halogenating agent has the formula Ti(OR e ) f X h wherein R eand X is defined as above, f is an integer from 0 to 3, h is an integer from 1 to 4, and f+h is 4. In one embodiment, the halogenating agent is TiCl4. In a further embodiment, the halogenation is carried out in the presence of a chlorinated or non-chlorinated aromatic liquid, such as dichlorobenzene, o-chlorotoluene, chlorobenzene, benzene, toluene, or xylene. In yet another embodiment, the halogenation is carried out by use of a mixture of a halogenating agent and a chlorinated aromatic liquid, the mixture comprising 40 to 60 volume percent of the halogenating agent, such as TiCl4.

[0075] The reaction mixture may be heated during halogenation. The catalyst components and the halogenating agent are initially contacted at a temperature below about 10° C., such as below about 0° C., such as below about −10° C., such as below about −20° C., such as below about −30° C. The initial temperature is generally greater than about −50° C., such as greater than about −40° C. The mixture is then heated at a rate of 0.1-10.0° C. / min, or at a rate of 1.0-5.0° C. / min. The internal electron donor may be added later, after the initial contact period between the halogenating agent and the catalyst components. The temperature of the halogenation is 20° C. to 150° C. (or any value or subrange therebetween), or 0° C. to 120° C. The halogenation may be continued for a period of 5-60 minutes, or 10-50 minutes, in the substantial absence of the internal electron donor.

[0076] The manner of contacting the catalyst components, halogenation agent, and internal electron donor can vary. In one embodiment, the catalyst components are first contacted with a mixture containing a halogenation agent and a chlorinated aromatic compound. The resulting mixture can be stirred and heated as needed. The internal electron donor is then added to the same reaction mixture without isolating or recovering the precursor. The aforementioned process can be carried out in a single reactor with the addition of the various components controlled by an automatic process control.

[0077] In one embodiment, the catalyst component is contacted with an internal electron donor prior to reacting with the halogenating agent.

[0078] The contact time between the catalyst component and the internal electron donor is at least 10 minutes, or at least 15 minutes, or at least 20 minutes, or at least 1 hour, at a temperature of at least -30°C, or at least -20°C, or at least 10°C up to 150°C, up to 120°C, or up to 115°C, or up to 110°C.

[0079] In one embodiment, the catalyst components, the internal electron donor, and the halogenating agent are added simultaneously or substantially simultaneously.

[0080] The halogenation procedure can be repeated once, twice, three times, or more times as necessary. In one embodiment, the resulting solid material is withdrawn from the reaction mixture and contacted one or more times in the absence (or presence) of the same (or different) internal electron donor component as the mixture of halogenating agents in the chlorinated aromatic compound at a temperature of at least about -20°C or at least about 0°C, or at least about 10°C to at most about 150°C, or at most about 120°C, or at most about 115°C for at least about 10 minutes, or at least about 15 minutes, or at least about 20 minutes, and up to about 10 hours, or up to about 45 minutes, or up to about 30 minutes.

[0081] After the aforementioned halogenation procedure, the resulting solid catalyst composition is separated from the reaction medium used in the final process, for example by filtration to produce a wet filter cake. The wet filter cake can then be rinsed or washed with a liquid diluent to remove unreacted TiCl4, and optionally dried to remove residual liquid. Typically, the resulting solid catalyst composition is washed one or more times with a "wash liquid", which is a liquid hydrocarbon, such as isopentane, isooctane, isohexane, hexane, pentane, or an aliphatic hydrocarbon, such as octane. The solid catalyst composition can then be separated and dried, or slurried in a hydrocarbon, particularly a relatively heavy hydrocarbon, such as mineral oil, for further storage or use.

[0082] In one embodiment, the resulting solid catalyst composition has a titanium content of about 1.0 weight percent to about 6.0 weight percent, or about 1.5 weight percent to about 4.5 weight percent, or about 2.0 weight percent to about 3.5 weight percent based on the total solids weight. The weight ratio of titanium to magnesium in the solid catalyst composition is preferably about 1:3 to about 1:160, or about 1:4 to about 1:50, or about 1:6 to 1:30. In one embodiment, the internal electron donor may be present in the catalyst composition in a molar ratio of internal electron donor to magnesium of about 0.005:1 to about 1:1, or about 0.01:1 to about 0.4:1. The weight percentages are based on the total weight of the catalyst composition.

[0083] The catalyst composition may be further treated by one or more of the following procedures before or after isolation of the solid catalyst composition. If desired, the solid catalyst composition may be contacted with an additional amount of a titanium halide compound (halogenation). It may be exchanged under metathesis conditions with an acid chloride such as phthaloyl dichloride or benzoyl chloride, rinsed or washed, heat treated, or aged. The aforementioned additional procedures may be combined in any order, used separately, or not used at all.

[0084] As discussed above, the catalyst composition may include a combination of magnesium moieties, titanium moieties, and an internal electron donor. The catalyst composition is produced by the halogenation procedure described above, which converts the catalyst components and the internal electron donor into a combination of magnesium and titanium moieties incorporating an internal electron donor. The catalyst components from which the catalyst composition is formed may be any of the catalyst precursors described above, including magnesium moiety precursors, mixed magnesium / titanium precursors, benzoic acid-containing magnesium chloride precursors, magnesium, titanium, epoxy, and phosphorus precursors, or spherical precursors.

[0085] A variety of different types of internal electron donors may be incorporated into the solid catalyst component. In one embodiment, the internal electron donor is an aryl diester, such as a phenylene substituted diester. In one embodiment, the internal electron donor may have the following chemical structure:

[0086] [ka] In the formula, R1, R2, R3, and R4 are each a hydrocarbyl group having 1 to 20 carbon atoms, the hydrocarbyl group having a branched or linear structure or including a cycloalkyl group having 7 to 15 carbon atoms; E1 and E2 may be the same or different and are selected from the group consisting of an alkyl having 1 to 20 carbon atoms, a substituted alkyl having 1 to 20 carbon atoms, an aryl having 1 to 20 carbon atoms, a substituted aryl having 1 to 20 carbon atoms, or an inert functional group having 1 to 20 carbon atoms and optionally containing a heteroatom; X1 and X2 are each O, S, an alkyl group, or NR5, and R5 is a hydrocarbyl group having 1 to 20 carbon atoms or hydrogen.

[0087] As used herein, the terms "hydrocarbyl" and "hydrocarbon" refer to substituents containing only hydrogen and carbon atoms, including branched or unbranched, saturated or unsaturated, cyclic, polycyclic, fused, or acyclic species, and combinations thereof. Non-limiting examples of hydrocarbyl groups include alkyl, cycloalkyl, alkenyl, alkadienyl, cycloalkenyl, cycloalkadienyl, aryl, aralkyl, alkylaryl, and alkynyl groups.

[0088] As used herein, the terms "substituted hydrocarbyl" and "substituted hydrocarbon" refer to a hydrocarbyl group substituted with one or more non-hydrocarbyl substituents. A non-limiting example of a non-hydrocarbyl substituent is a heteroatom. As used herein, "heteroatom" refers to an atom other than carbon or hydrogen. A heteroatom can be a non-carbon atom from Groups IV, V, VI, and VII of the periodic table. Non-limiting examples of heteroatoms include halogens (F, Cl, Br, I), N, O, P, B, S, and Si. Substituted hydrocarbyl groups also include halohydrocarbyl groups and silicon-containing hydrocarbyl groups. As used herein, the term "halohydrocarbyl" group refers to a hydrocarbyl group substituted with one or more halogen atoms. As used herein, the term "silicon-containing hydrocarbyl group" is a hydrocarbyl group substituted with one or more silicon atoms. The silicon atom may or may not be in the carbon chain.

[0089] In one embodiment, the substituted phenylenediester has the following structure (I):

[0090] [ka]

[0091] In one embodiment, structure (I) includes R1 and R3 that are isopropyl groups. R2, R4, and R5 through R 14 Each of is hydrogen.

[0092] In one embodiment, structure (I) comprises R, R, and R 10 R2, R4, R6 to R9, and R 11 ~R 14 Each of is hydrogen.

[0093] In one embodiment, structure (I) comprises R, R, and R 12 Each of R2, R4, R5, R6, R8, R9, R10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0094] In one embodiment, structure (I) includes R1 as a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0095] In one embodiment, structure (I) is selected from the group consisting of R1, R5, R7, R9, R 10 , R 12 , and R 14 R2, R4, R6, R8, R 11 , and R 13 Each of is hydrogen.

[0096] In one embodiment, structure (I) includes R1 as a methyl group and R3 is a t-butyl group. 10 , R 12 , and R 14 Each of R2, R4, R6, R8, R 11 , and R 13 Each of is hydrogen.

[0097] In one embodiment, the substituted phenylene aromatic diester is selected from the group consisting of R1-R2, as described in detail in U.S. Pat. No. 8,536,372, which is incorporated herein by reference. 14 The compound has a structure selected from the group consisting of structures (II)-(V), including alternatives of each of the following:

[0098] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R13 , and R 14 Each of is hydrogen.

[0099] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0100] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0101] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0102] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0103] In one embodiment, structure (I) comprises R1 being a methyl group and R3 being a t-butyl group. 11 , and R 12 Each of R2, R4, R5, R8, R9, R10 , R 13 , and R 14 Each of is hydrogen.

[0104] In one embodiment, structure (I) comprises R1 being a methyl group and R3 being a t-butyl group. 11 , and R 13 Each of R2, R4, R5, R7, R9, R 10 , R 12 , and R 14 Each of is hydrogen.

[0105] In one embodiment, structure (I) includes R1 which is a methyl group, and R3 is a t-butyl group. 14 Each of is a fluorine atom.

[0106] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0107] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0108] In one embodiment, R1 is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0109] In one embodiment, structure (I) includes R1 which is a methyl group and R3 is a t-butyl group. 12 Each of R2, R4, R5, R6, R8, R9, R 10 , R 11 , R 13 , and R 14 Each of is hydrogen.

[0110] In one embodiment, structure (I) includes R1 which is a methyl group, and R3 is a 2,4,4-trimethylpentan-2-yl group. 14 Each of is hydrogen.

[0111] In one embodiment, structure (I) comprises R1 and R3, each of which is a sec-butyl group. R2, R4, and R5 through R 14 Each of is hydrogen.

[0112] In one embodiment, structure (I) includes R1 and R4, each of which is a methyl group. R2, R3, R5-R9, and R 10 ~R 14 Each of is hydrogen.

[0113] In one embodiment, structure (I) includes R1 which is a methyl group. R4 is an i-propyl group. R2, R3, R5-R9, and R 10 ~R 14 Each of is hydrogen.

[0114] In one embodiment, structure (I) includes R1, R3, and R4, each of which is an i-propyl group. R2, R5-R9, and R 10 ~R 14 Each of is hydrogen.

[0115] In another embodiment, the internal electron donor can be a phthalate compound. For example, the phthalate compound can be dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, dibutyl phthalate, diisobutyl phthalate, diamyl phthalate, diisoamyl phthalate, methyl butyl phthalate, ethyl butyl phthalate, or ethyl propyl phthalate.

[0116] In addition to the solid catalyst component described above, the Ziegler-Natta catalyst system of the present disclosure can also include a cocatalyst. The cocatalyst can include hydrides of aluminum, lithium, zinc, tin, cadmium, beryllium, magnesium, alkyl, or aryl, and combinations thereof. In one embodiment, the cocatalyst is a hydrocarbyl aluminum cocatalyst represented by the formula R3Al, where each R is an alkyl, cycloalkyl, aryl, or hydride group, at least one R is a hydrocarbyl group, and two or three R groups can be connected to a cyclic group to form a heterocyclic structure, each R can be the same or different, and each R, which is a hydrocarbyl group, has 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms. In further embodiments, each alkyl group can be linear or branched, and such hydrocarbyl groups can be mixed groups, i.e., the group can contain alkyl, aryl, and / or cycloalkyl groups. Non-limiting examples of suitable groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, 2-methylpentyl, n-heptyl, n-octyl, isooctyl, 2-ethylhexyl, 5,5-dimethylhexyl, n-nonyl, n-decyl, isodecyl, n-undecyl, and n-dodecyl.

[0117] Non-limiting examples of suitable hydrocarbyl aluminum compounds are: triisobutylaluminum, tri-n-hexylaluminum, diisobutylaluminum hydride, di-n-hexylaluminum hydride, isobutylaluminum dihydride, n-hexylaluminum dihydride, diisobutylhexylaluminum, isobutyldihexylaluminum, trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, tri-n-octylaluminum, tri-n-decylaluminum, or tri-n-dodecylaluminum. In one embodiment, the cocatalyst is selected from triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, diisobutylaluminum hydride, or di-n-hexylaluminum hydride.

[0118] In one embodiment, the cocatalyst is triethylaluminum. The molar ratio of aluminum to titanium is from about 5:1 to about 500:1, or from about 10:1 to about 200:1, or from about 15:1 to about 150:1, or from about 20:1 to about 100:1. In another embodiment, the molar ratio of aluminum to titanium is about 45:1.

[0119] A suitable catalyst composition may include a solid catalyst component, a cocatalyst, and an external electron donor, which may be a mixed external electron donor (M-EED) of two or more different components. Suitable external electron donors or "external donors" include one or more selectivity control agents (SCAs) and / or one or more activity limiting agents (ALAs). As used herein, an "external donor" is a composition that includes a component or mixture of components that are added independently of the procatalyst formation to modify the catalyst performance. As used herein, an "activity limiting agent" is a composition that reduces the catalyst activity in the presence of the catalyst as the polymerization temperature increases above a threshold temperature (e.g., a temperature above about 95°C). A "selectivity control agent" is a composition that improves the tacticity of the polymer, where improved tacticity is generally understood to mean increased tacticity or decreased xylene solubles, or both. It should be understood that the above definitions are not mutually exclusive and that a single compound may, for example, be classified as both an activity limiting agent and a selectivity controlling agent.

[0120] The selectivity control agent according to the present disclosure is generally an organosilicon compound. For example, in one embodiment, the selectivity control agent can be an alkoxysilane.

[0121] In one embodiment, the alkoxysilane has the general formula: SiR m (OR') 4-m (I), where R is independently, at each occurrence, a hydrocarbyl or amino group optionally substituted with one or more substituents containing one or more Group 14, 15, 16, or 17 heteroatoms, said R containing up to 20 atoms excluding hydrogen and halogens, and R′ is C 1~4 In one embodiment, R is an alkyl group, and m is 0, 1, 2, or 3. In one embodiment, R is 6~12 Aryl, alkyl or aralkyl, C 3~12 Cycloalkyl, C 3~12 Branched alkyl, or C 3~12 is a cyclic or acyclic amino group, R' is C 1~4alkyl and m is 1 or 2. In one embodiment, for example, the second selectivity control agent can include n-propyltriethoxysilane. Other selectivity control agents that can be used include propyltriethoxysilane and / or diisobutyldimethoxysilane.

[0122] In one embodiment, the catalyst system may include an activity limiting agent (ALA). The ALA inhibits or otherwise prevents polymerization reactor failure and ensures the continuation of the polymerization process. Typically, the activity of Ziegler-Natta catalysts increases as the reactor temperature increases until it reaches a very high level. Ziegler-Natta catalysts also typically maintain high activity near the melting point temperature of the polymer produced. The heat generated by the exothermic polymerization reaction can cause the polymer particles to form agglomerates, which may ultimately lead to the interruption of the continuation of the polymer production process. The ALA reduces the catalyst activity at high temperatures, thereby preventing reactor failure and reducing (or preventing) particle agglomeration, ensuring the continuation of the polymerization process.

[0123] The activity limiting agent may be a carboxylic acid ester. The aliphatic carboxylic acid ester may be a C4-C 30 It may be an aliphatic acid ester, may be a mono- or poly(two or more) ester, may be linear or branched, may be saturated or unsaturated, and may be any combination thereof. 30 The aliphatic acid esters may also be substituted with one or more Group 14, 15, or 16 heteroatom-containing substituents. 4~30 Non-limiting examples of aliphatic acid esters include aliphatic C 4~30 Monocarboxylic acid C 1~20 Alkyl ester, aliphatic C 8~20 Monocarboxylic acid C 1~20 Alkyl ester, aliphatic C 4~20 Monocarboxylic and dicarboxylic acids C 1~4 Allyl mono- and diesters, aliphatic C 8~20 Monocarboxylic and dicarboxylic acids C 1~4 Alkyl esters, and C2~100 (Poly)glycol or C 2~100 (Poly)glycol ether C 4~20 In a further embodiment, the C4 to C6 30 The fatty acid esters include laurate, myristate, palmitate, stearate, oleate, sebacate, (poly)(alkylene glycol) mono- or diacetate, (poly)(alkylene glycol) mono- or dimyristate, (poly)(alkylene glycol) mono- or dilaurate, (poly)(alkylene glycol) mono- or dioleate, glyceryl tri(acetate), C2- 40 glyceryl tri-esters of aliphatic carboxylic acids, and mixtures thereof. In further embodiments, C4-C 30 The aliphatic esters are isopropyl myristate, di-n-butyl sebacate and / or pentyl valerate.

[0124] In one embodiment, the selectivity control agent and / or activity limiting agent may be added separately into the reactor. In another embodiment, the selectivity control agent and activity limiting agent may be premixed together and then added as a mixture into the reactor. In addition, the selectivity control agent and / or activity limiting agent may be added to the reactor in different ways. For example, in one embodiment, the selectivity control agent and / or activity limiting agent may be added directly to the reactor, such as a fluidized bed reactor. Alternatively, the selectivity control agent and / or activity limiting agent may be added indirectly to the reactor volume, for example, by feeding through a cycle loop (e.g., line 22 in FIG. 1). The selectivity control agent and / or activity limiting agent may be combined with the reactor cycle gas in the cycle loop before being fed to the reactor.

[0125] In addition to Ziegler-Natta catalysts, the disclosed processes and systems can also use metallocene catalysts. Metallocene catalysts can include "half sandwich" and "full sandwich" compounds having one or more Cp ligands (cyclopentadienyl and ligands isotropic to cyclopentadienyl) bonded to at least one Group 3 to Group 12 metal atom and one or more leaving groups bonded to at least one metal atom.

[0126] The Cp ligands are one or more rings or ring systems, at least some of which contain a π-bond system, such as cycloalkadienyl ligands and heterocyclic analogs. The rings or ring systems typically contain atoms selected from Groups 13-16, and in some embodiments, the atoms constituting the Cp ligands are selected from carbon, nitrogen, oxygen, silicon, sulfur, phosphorus, germanium, boron, aluminum, and combinations thereof, with carbon constituting at least 50% of the ring members. For example, the Cp ligands may be selected from substituted and unsubstituted cyclopentadienyl ligands and ligands that are isoloval to cyclopentadienyl. Non-limiting examples of such ligands include cyclopentadienyl, cyclopentaphenanthrenyl, indenyl, benzoindenyl, fluorenyl, octahydrofluorenyl, cyclooctatetraenyl, cyclopentacyclododecene, phenanthrindenyl, 3,4-benzofluorenyl, 9-phenylfluorenyl, 8-H-cyclopento[a]acenaphthylenyl, 7-H-dibenzofluorenyl, indeno[1,2-9]anthrene, thiophenoindenyl, thiophenofluorenyl, hydrogenated versions thereof (e.g., 4,5,6,7-tetrahydroindenyl, or "H4Ind"), substituted versions thereof (discussed and described in more detail below), and heterocyclic versions thereof.

[0127] The metal atom "M" of the metallocene compound may be selected from Groups 3-12 and Lanthanide atoms, or may be selected from Groups 3-10 atoms, or may be selected from Sc, Ti, Zr, Hf, V, Nb, Ta, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, and Ni, or may be selected from Groups 4, 5, and 6 atoms, or may be Ti, Zr, or Hf atoms, or may be Hf, or may be Zr. The oxidation state of the metal atom "M" may range from 0 to +7, or may be +1, +2, +3, +4, or +5, or may be +2, +3, or +4. The groups bonded to the metal atom "M" are such that the compounds described in the structures and structures below are electrically neutral, unless otherwise indicated. The Cp ligand forms at least one chemical bond with the metal atom M to form the "metallocene catalyst component". The Cp ligands differ from leaving groups attached to the metal atom M in that they do not undergo significant substitution / abstraction reactions.

[0128] In one embodiment, the metallocene catalyst has the formula: (C5R x ) y R' z (C5R m )MQ n-y-1 It may be represented by:

[0129] In the above formula, M is a metal from group IIIB to VIII of the periodic table of elements, (C5R x ) and (C5R m ) are the same or different cyclopentadienyl or substituted cyclopentadienyl groups bonded to M, R are the same or different and are hydrogen or a hydrocarbyl group such as an alkyl, alkenyl, aryl, alkylaryl, or arylalkyl group containing 1 to 20 carbon atoms, or two carbon atoms joined together to form a C4-C6 ring, R' is a C1-C4 substituted or unsubstituted alkylene group, a dialkyl or diaryl germanium or silicon, or two (C5R x ) and (C5R mQ is a hydrocarbyl group such as an aryl, alkyl, alkenyl, alkylaryl, or arylalkyl group having 1 to 20 carbon atoms, a hydrocarboxy group having 1 to 20 carbon atoms, or a halogen, which may be the same or different from each other, z is 0 or 1, y is 0, 1, or 2, and when y is 0, z is 0, n is 0, 1, 2, 3, or 4 depending on the valence state of M, and ny>1.

[0130] Illustrative, but non-limiting examples of metallocenes represented by the formula above include dialkyl metallocenes, such as bis(cyclopentadienyl)titanium dimethyl, bis(cyclopentadienyl)titanium diphenyl, bis(cyclopentadienyl)zirconium dimethyl, bis(cyclopentadienyl)zirconium diphenyl, bis(cyclopentadienyl)hafnium dimethyl and diphenyl, bis(cyclopentadienyl)titanium di-neopentyl, bis(cyclopentadienyl)zirconium di-neopentyl, bis(cyclopentadienyl)hafnium ... cyclopentadienyl)titanium dibenzyl, bis(cyclopentadienyl)zirconium dibenzyl, bis(cyclopentadienyl)vanadium dimethyl; monoalkyl metallocenes, such as bis(cyclopentadienyl)titanium methyl chloride, bis(cyclopentadienyl)titanium ethyl chloride, bis(cyclopentadienyl)titanium phenyl chloride, bis(cyclopentadienyl)zirconium methyl chloride, bis(cyclopentadienyl)zirconium ethyl chloride, bis(cyclopentadienyl)zirconium cyclopentadienyl phenyl chloride, bis(cyclopentadienyl)titanium methyl bromide; trialkyl metallocenes such as cyclopentadienyl titanium trimethyl, cyclopentadienyl zirconium triphenyl, and cyclopentadienyl zirconium trineopentyl, cyclopentadienyl zirconium trimethyl, cyclopentadienyl hafnium triphenyl, cyclopentadienyl hafnium trineopentyl, and cyclopentadienyl hafnium trimethyl; monocyclopentadienyl titanocenes such as penta Methylcyclopentadienyltitanium trichloride, pentaethylcyclopentadienyltitanium trichloride; bis(pentamethylcyclopentadienyl)titanium diphenyl, carbenes represented by the formula bis(cyclopentadienyl)titanium=CH2 and derivatives of this reagent; substituted bis(cyclopentadienyl)titanium(IV) compounds, such as bis(indenyl)titanium diphenyl or dichloride, bis(methylcyclopentadienyl)titanium diphenyl or dihalides; dialkyl, trialkyl,Tetra-alkyl and penta-alkyl cyclopentadienyl titanium compounds, such as bis(1,2-dimethylcyclopentadienyl)titanium diphenyl or dichloride, bis(1,2-diethylcyclopentadienyl)titanium diphenyl or dichloride; silicon, phosphine, amine or carbon bridged cyclopentadiene complexes, such as dimethylsilyldicyclopentadienyltitanium diphenyl or dichloride, methylphosphinedicyclopentadienyltitanium diphenyl or dichloride, methylenedicyclopentadiene, enyltitanium diphenyl or dichloride and other dihalide complexes; and bridged metallocene compounds such as isopropyl(cyclopentadienyl)(fluorenyl)zirconium dichloride, isopropyl(cyclopentadienyl)(octahydrofluorenyl)zirconium dichloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconium dichloride, diisopropylmethylene(cyclopentadienyl)(fluorenyl)zirconium dichloride, diisobutylmethylene(cyclopentadienyl) (Fluorenyl)zirconium dichloride, di-tert-butylmethylene(cyclopentadienyl)(fluorenyl)zirconium dichloride, cyclohexylidene(cyclopentadienyl)(fluorenyl)zirconium dichloride, diisopropylmethylene(2,5-dimethylcyclopentadienyl)(fluorenyl)zirconium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)hafnium dichloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)hafnium dichloride, diisopropylmethylene diisobutylmethylene(cyclopentadienyl)(fluorenyl)hafnium dichloride, ditertbutylmethylene(cyclopentadienyl)(fluorenyl)hafnium dichloride, cyclohexylidene(cyclopentadienyl)(fluorenyl)hafnium dichloride, diisopropylmethylene(2,5-dimethylcyclopentadienyl)(fluorenyl)hafnium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)titanium dichloride,Diphenylmethylene(cyclopentadienyl)(fluorenyl)titanium dichloride, diisopropylmethylene(cyclopentadienyl)(fluorenyl)titanium dichloride, diisobutylmethylene(cyclopentadienyl)(fluorenyl)titanium dichloride, ditert-butylmethylene(cyclopentadienyl)(fluorenyl)titanium dichloride, cyclohexylidene(cyclopentadienyl)(fluorenyl)titanium dichloride, diisopropylmethylene(2,5-dimethylcyclopentadienyl) racemic-ethylenebis(1-indenyl)zirconium(IV) dichloride, racemic-ethylenebis(4,5,6,7-tetrahydro-1-indenyl)zirconium(IV) dichloride, racemic-dimethylsilylbis(1-indenyl)zirconium(IV) dichloride, racemic-dimethylsilylbis(4,5,6,7-tetrahydro-1-indenyl)zirconium(IV) dichloride, racemic-1,1,2,2-tetramethylsilanylenebis(1-indenyl)zirconium racemic-1,1,2,2-tetramethylsilanylenebis(4,5,6,7-tetrahydro-1-indenyl)zirconium(IV) dichloride, ethylidene(1-indenyltetramethylcyclopentadienyl)zirconium(IV) dichloride, racemic-dimethylsilylbis(2-methyl-4-t-butyl-1-cyclopentadienyl)zirconium(IV) dichloride, racemic-ethylenebis(1-indenyl)hafnium(IV) dichloride, racemic-ethylenebis(4,5,6,7- tetrahydro-1-indenyl)hafnium(IV) dichloride, racemic-dimethylsilylbis(1-indenyl)hafnium(IV) dichloride, racemic-dimethylsilylbis(4,5,6,7-tetrahydro-1-indenyl)hafnium(IV) dichloride, racemic-1,1,2,2-tetramethylsilanylenebis(1-indenyl)hafnium(IV) dichloride, racemic-1,1,2,2-tetramethylsilanylenebis(4,5,6,7-tetrahydro-1-indenyl)hafnium(IV), dichloride,Ethylidene(1-indenyl-2,3,4,5-tetramethyl-1-cyclopentadienyl)hafnium(IV) dichloride, racemic ethylenebis(1-indenyl)titanium(IV) dichloride, racemic ethylenebis(4,5,6,7-tetrahydro-1-indenyl)titanium(IV) dichloride, racemic dimethylsilylbis(1-indenyl)titanium(IV) dichloride, racemic dimethylsilylbis(4,5,6,7-tetrahydro-1-indenyl)titanium(IV) dichloride racemic-1,1,2,2-tetramethylsilanylenebis(4,5,6,7-tetrahydro-1-indenyl)titanium(IV) dichloride, racemic-1,1,2,2-tetramethylsilanylenebis(4,5,6,7-tetrahydro-1-indenyl)titanium(IV) dichloride, or ethylidene(1-indenyl-2,3,4,5-tetramethyl-1-cyclopentadienyl)titanium(IV) dichloride.

[0131] Cocatalysts may also be used with the metallocene catalyst. The cocatalyst may be, for example, an aluminoxane. Cocatalysts that may be used include those having the general formula: M 3 M 4 v X 2 c R 3 b-c

[0132] In the above formula, M 3 are metals of groups IA, IIA and IIIA of the periodic table, and M 4 is a metal in Group IA of the periodic table, v is a number between 0 and 1, and each X 2 is any halogen, c is a number from 0 to 3, and each R 3 is a monovalent hydrocarbon group or hydrogen, b is a number from 1 to 4, and bc is at least 1.

[0133] Compounds having only one Group IA, IIA or IIIA metal suitable for the practice of the present invention include compounds having the formula: M 3 R3 k

[0134] In the above formula, M 3 is a metal of Group IA, Group IIA or Group IIIA, such as lithium, sodium, beryllium, barium, boron, aluminum, zinc, cadmium and gallium. k is M 3 is equal to 1, 2 or 3 depending on the valence of M 3 Depending on the particular group (i.e., IA, IIA, or IIIA) to which each R 3 can be any monovalent hydrocarbon group. 3 Examples of groups include those R 3 The examples include any of the groups.

[0135] The invention having thus been generally described will be more readily understood with reference to the following examples, which are provided by way of illustration and are not intended to limit the invention. EXAMPLES

[0136] The following examples have been completed to demonstrate some of the benefits and advantages of the present disclosure.

[0137] A gas phase polymerization reactor similar to that shown in Figures 1 and 2 was operated with different catalyst particles in the catalyst stream. In these examples, a Ziegler-Natta catalyst was used.

[0138] The gas phase polymerization reactor was operated to produce a polypropylene homopolymer having a target melt flow rate of about 3-45 g / 10 min and a xylene solubles content of about 2.5%.

[0139] Example 1. Using the Ziegler-Natta catalyst shown in Examples 9-10 of US Pat. No. 9,593,182 and the external donor shown in Example B1 of US Patent Application Publication No. 2011 / 0152067(A1), a polypropylene homopolymer having a melt flow rate of 45 g / 10 min and a xylene soluble content of 2.5% was produced in a commercial scale gas phase fluidized bed polymerization reactor at a production rate of 37,500 kg per hour, a reactor temperature of 70° C., and a total reactor pressure of 3.1 MPa. The melt flow rate was measured under conditions of 2.16 kg load and 230° C. according to ASTM D1238-01. The xylene soluble content was measured according to ASTM D5492. Vaporized propylene gas at 125° C. was used as the support gas for catalyst injection. The catalyst injection system included a central catalyst injection tube with OD of 0.375 in. (9.53 mm) and ID of 0.305 in. (7.7 mm) and a coaxial support tube with ID of 15 / 32 in. (11.9 mm). It resulted in a cross-sectional area ratio of the support gas passage to the catalyst inlet tube of about 0.85 (based on the ID of the tube). Two different test runs were performed with this catalyst. During each test run, all conditions remained the same except for the velocity of the support gas flow. The conditions were maintained stable for more than 16 hours to ensure very stable operation. When the velocity was adjusted to 61 m / s, the average settled bulk density obtained was 413 kg / m 3 Then, when the speed was reduced to 16 m / s, the settled bulk density was 372 kg / m 3 It fell to.

[0140] Example 2. Using the Ziegler-Natta catalyst shown in Examples 4-6 of US Pat. No. 5,093,415 and the external donor shown in Example I1 of US Patent Application Publication No. 2011 / 0152067(A1), a polypropylene homopolymer with a melt flow rate of 3.3 g / 10 min and a xylene soluble content of 2.5% was produced in a commercial-scale gas-phase fluidized bed polymerization reactor at a production rate of 37,500 kg per hour, a reactor temperature of 70° C., and a total reactor pressure of 3.1 MPa. Vaporized propylene gas at 125° C. was used as the support gas for catalyst injection. The catalyst injection system is the same as in Example 1. Two different trial runs were performed with this catalyst. During each trial run, all conditions remained the same except for the rate of the support gas flow. The conditions were maintained stable for more than 24 hours to ensure a very stable operation. When the velocity was adjusted to 57 m / s, the average settled bulk density obtained was 260 kg / m 3 Then, when the velocity was reduced to 38 m / s, the average settled bulk density was 297 kg / m 3 increased to.

[0141] As shown above, for some Ziegler-Natta catalysts, increasing the velocity of the supporting gas flow dramatically improved the settled bulk density, however, for other Ziegler-Natta catalysts, decreasing the velocity of the supporting gas flow resulted in higher settled bulk density.

[0142] While particular embodiments have been illustrated and described, it should be understood that changes and modifications may be made therein by those skilled in the art without departing from the technology in its broader aspects as defined in the following claims.

[0143] The embodiments illustratively described herein may suitably be practiced in the absence of any element or elements, limitations or limitations not specifically disclosed herein. Thus, for example, terms such as "comprising", "including", "containing" and the like should be read expansively and without limitation. In addition, the terms and expressions used herein are used as terms of description and not of limitation, and in the use of such terms and expressions, there is no intention to exclude any equivalents of the shown and described features or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. In addition, the phrase "consisting essentially of" will be understood to include those elements specifically recited, as well as those additional elements that do not materially affect the basic and novel features of the claimed technology. The phrase "consisting of" excludes any elements not specified.

[0144] The present disclosure is not limited with respect to the specific embodiments described in this application. As will be apparent to those skilled in the art, many modifications and variations can be made without departing from the spirit and scope of the present invention. In addition to those recited herein, functionally equivalent methods and compositions within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that the disclosure is not limited to particular methods, reagents, compounds, compositions, or biological systems, which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0145] Additionally, when features or aspects of the disclosure are described in terms of a Markush group, one of skill in the art will recognize that the disclosure is also thereby described in terms of any individual members or subgroups of members of the Markush group.

[0146] As will be understood by those skilled in the art, for any and all purposes, especially in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations thereof. It can be easily recognized that any recited range fully describes and allows for the same range to be subdivided into at least two, three, four, five, ten, etc. As a non-limiting example, each range discussed herein can be easily subdivided into a lower third, a middle third, an upper third, etc. Also, as will be understood by those skilled in the art, all terms such as "up to," "at least," "greater than," "less than," etc. refer to ranges that include the recited numbers and can then be subdivided into the subranges discussed above. Finally, as will be understood by those skilled in the art, a range includes each individual member.

[0147] All publications, patent applications, issued patents, and other documents referenced herein are incorporated by reference as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions contained in the descriptions incorporated by reference are excluded to the extent that they contradict definitions in this disclosure.

[0148] Other embodiments are within the scope of the following claims.

Claims

1. 1. A process for increasing the settled bulk density of a particulate polyolefin polymer, said process comprising: feeding a catalyst stream to a gas phase polymerization reactor, said catalyst stream comprising catalyst particles optionally in slurry form by suspension in mineral oil and / or other hydrocarbon liquid contained in a carrier fluid; feeding a support gas into the gas phase polymerization reactor along with the catalyst flow entering the reactor, the support gas being fed into the gas phase reactor at a rate; forming polyolefin particles by contacting the catalyst particles with a monomer, and optionally one or more comonomers, in the gas phase polymerization reactor; determining a settled bulk density of the granular polyolefin particles; and selectively increasing or decreasing the velocity of the support gas based on the settled bulk density to maintain the settled bulk density above a preset limit.

2. 2. The process of claim 1, wherein the catalyst flow enters the gas-phase polymerization reactor through a catalyst inlet having a cross-sectional area, and the support gas flows into the gas-phase polymerization reactor through a gas feed inlet having a cross-sectional area within 0.25 to 4.0 times the cross-sectional area of the catalyst inlet.

3. 10. The process of claim 1, wherein the support gas flows into the gas phase polymerization reactor in a concentric manner with the catalyst flow.

4. The process of claim 1 , wherein the supporting gas comprises a monomer gas, an inert gas, or a mixture thereof.

5. The process of claim 1 , wherein the support gas comprises propylene gas.

6. The process of claim 1 , wherein the supporting gas comprises an inert gas.

7. The process of claim 1 , wherein the carrier fluid comprises liquid propylene.

8. The process of claim 1 , wherein the carrier fluid comprises an inert gas, such as nitrogen gas.

9. 10. The process of claim 1, wherein the velocity of the supporting gas is adjusted to between about 5.4 m / s and about 81 m / s.

10. The process of any one of claims 1 to 9, wherein the catalyst particles comprise a Ziegler-Natta catalyst.

11. The preset limit of settled bulk density is about 250 kg / m ３ The process of any one of claims 1 to 9, wherein the

12. The preset limit of settled bulk density is about 350 kg / m ３ The process of any one of claims 1 to 9, wherein the

13. The preset limit of settled bulk density is about 400 kg / m ３ The process of any one of claims 1 to 9, wherein the

14. The process of any one of claims 1 to 9, wherein the support gas enters the gas phase polymerization reactor at a temperature of from about 100°C to about 150°C.

15. 11. The process of claim 10, wherein the Ziegler-Natta catalyst comprises a solid catalyst component comprising a magnesium portion, a titanium portion, and an internal electron donor.

16. 16. The process of claim 15, wherein the Ziegler-Natta catalyst further comprises at least one cocatalyst, at least one external electron donor comprising at least one selectivity control agent, and optionally at least one activity limiting agent.

17. 16. The process of claim 15, wherein the internal electron donor comprises a substituted phenylenediester.

18. 16. The process of claim 15, wherein the solid catalyst component further comprises an organosilicon compound and an epoxy compound.

19. The process of any one of claims 1 to 9, wherein the catalyst particles comprise a metallocene catalyst.

20. The metallocene catalyst is represented by the general formula (C ５ R ｘ ) ｙ R' ｚ (C ５ R ｍ ) MQ ｎ－ｙ－１ and During the ceremony, M is a metal from Groups III to VIII of the Periodic Table of the Elements; (C ５ R ｘ ) and (C ５ R ｍ ) are the same or different cyclopentadienyl or substituted cyclopentadienyl groups attached to M; R are the same or different and are hydrogen or hydrocarbyl groups such as alkyl, alkenyl, aryl, alkylaryl, or arylalkyl groups containing 1 to 20 carbon atoms, or two carbon atoms joined together to form C ４ ~C ６ Forming a ring, R' is C １ ~C ４ a substituted or unsubstituted alkylene group, a dialkyl or diaryl germanium or silicon, or two (C ５ R ｘ ) and (C ５ R ｍ ) an alkyl or aryl phosphine or amine group bridging the rings; Q are the same or different hydrocarbyl groups such as aryl, alkyl, alkenyl, alkylaryl, or arylalkyl groups having 1 to 20 carbon atoms, hydrocarboxy groups having 1 to 20 carbon atoms, or halogen; z is 0 or 1, y is 0, 1 or 2, and when y is 0, then z is 0 and n is 0, 1, 2, 3, or 4 depending on the valence state of M; 20. The process of claim 19, wherein ny≧1.

21. The metallocene catalyst is represented by the general formula M ３ M ４ ｖ X ２ ｃ R ３ ｂ－ｃ and further comprising a cocatalyst of During the ceremony, M ３ are metals of Groups IA, IIA and IIIA of the Periodic Table; M ４ is a metal in Group IA of the periodic table, v is a number between 0 and 1, and each X ２ is any halogen, c is a number from 0 to 3, Each R ３ is a monovalent hydrocarbon group or hydrogen, b is a number from 1 to 4, 20. The process of claim 19, wherein bc is at least 1.

22. 10. The process of any one of claims 1 to 9, wherein the catalyst particles are in a slurry state before being combined with the carrier fluid, the slurry comprising the catalyst particles and an oil, such as mineral oil.

23. 10. The process of claim 1, wherein the determined settled bulk density is communicated to a controller, and the controller is configured to increase or decrease the velocity of the support gas based on the determined settled bulk density to increase the settled bulk density.

24. 23. The process of claim 22, wherein the control unit comprises one or more microprocessors.

25. 23. The process of claim 22, wherein the control operates in an open feed loop.

26. 23. The process of claim 22, wherein the control operates in a closed feed loop.

Images