The method of polymerization

 

(57) Abstract:

The invention relates to a method of continuous suspension or gas-phase polymerization of olefin(s) using as the catalyst the transition metal compounds with bulky ligand in the absence or in the presence of a small amount of the cleansing component. The method is carried out in the reactor in the absence of a metallocene catalyst system. The contents of the cleaning agent is from 0 to 10 ppm million of the total weight of the recirculation flow. However, the performance of the reactor is more than 500 lbs/HR (227 kg/HR) of polymer product, preferably from more than 500 to 200,000 lb/h (90900 kg/h) of polymer product. Also carried out in several stages in the reactor with a fluidized bed method for continuous gas-phase or suspension of polarizatio alpha-olefin monomers containing 2 to 20 carbon atoms, or copolymerization of one or more alpha-olefin monomers with another alpha-olefin, cycloolefin, styrene, polar vinyl monomers, diolefins, polyene, norbornene, norbornadiene, acetylene or aldehyde monomers. The stages are: enter the recirculation flow MES is following the termination of its input and/or input quantity, which provides the content of olefinic C14- C18oligomers in the polymer of less than 50 ppm million Then proceed stage exhaust, cooling, additional input of the monomer(s) in the stream, enter it in the reactor and the removal of the polymer product with a speed of more than 500 lb/HR (227 kg/HR), preferably from more than 500 lbs/HR (227 kg/HR) up to 200,000 lb/h (90900 kg/h). The technical result consists in increasing the efficiency of the reactor and obtaining polymers with improved physical properties. 2 C. and 22 C.p. f-crystals, 11 PL.

The invention relates to a method of continuous polymerization of olefin(s) using as the catalyst the transition metal compounds with bulky ligand, in particular to a method of continuous suspension or gas-phase polymerization. The invention primarily relates to a method of gas-phase polymerization in the polymerization of one or more olefins in the presence of a metallocene catalyst system in a reactor with a fluidized bed and in the absence or in the presence of a small amount of the cleansing component.

Background of the invention

It is well known that the processes of gas-phase and slurry polymerization in the presence of Katalizator, widely used in obtaining a variety of new polymers for use in various fields and products. In the art it is well known that these metallocene catalysts and catalytic systems have sufficient solubility in many liquids, in particular in such solvents or reactive components, which are used in a typical polymerization processes. In addition, metallocene catalysts can be subjected to chemical and physical effects of different components that are typically used in industrial polymerization processes. In the process of suspension or gas-phase polymerization metallocene catalyst components and components of catalytic systems have a tendency to cause clogging and/or the formation of deposits. Thus, in particular, in continuous suspension process fouling of the walls of the reactor, which perform the function of the heat exchanger can cause many problems, including a low rate of heat transfer in the polymerization process. Polymer particles which stick to the walls of the reactor, continue to cure and often splavov particular process fluidized bed.

In a continuous gas-phase process using a continuous recycle stream. This recycle stream is heated by heat of polymerization, and in another part of the cycle dissipate heat through the cooling system outside the reactor.

Clogging during continuous gas-phase process can lead to inefficiencies in the various reactor sites, for example, cooling system, temperature sensors and switch plates, it is often used in gas-phase process with fluidized bed.

To address the problems associated with the performance of the reactor in the case of metallocene catalysts and catalytic systems have been developed various methods of drawing or preparation of metallocene catalytic systems with weak tendency to clogging. So, for example, U.S. patent 5283218 refers to terpolymerization metallocene catalyst. In U.S. patent 5332706 proposed to use a special method of preparation of the catalyst, initial impregnation".

Although all these possible technical solutions can to some extent reduce the clogging or the formation of deposits, some of these roads to the I effective behavior of the continuous process, in particular, in industrial or large-scale production.

Thus, there is a need to create a method of polymerization, which can be performed continuously in an industrial environment to achieve increased efficiency of the reactor and the simultaneous achievement of polymers characterized by improved physical properties.

Summary of the invention

The present invention relates to a method of continuous suspension or gas-phase polymerization of one or more olefins using a catalyst based on transition metal compounds with bulky ligand, for example, a metallocene catalyst or catalytic system.

One of the embodiments of the invention relates to a method of continuous polymerization of one or more olefins (individually or in combination) in the presence of a metallocene catalyst system, and in this way provides for the elimination or reduction of the cleansing component.

In a preferred variant of the method according to the invention is carried out as the process of the suspension, preferably gas-phase polymerization.

In kugirango version.

Another variant implementation of the invention includes a method of continuous gas-phase or slurry polymerization of the monomer(s) in the reactor with a fluidized bed to obtain a polymer product, and this method includes the stages of (a) input of the recirculation flow in the reactor, where the recycle stream comprises the monomer(s); (b) input metallocene catalyst system into the reactor; (C) input, calculated on the total weight of the layer is less than 300 ppm million, preferably less than 250 ppm million cleansing agent, followed by the termination of the input cleansing agent and/or enter the number of the total weight of the layer, which ensures obtaining a polymer product comprising less than 50 weight.part./million olefinic C14-C18oligomers; (g) exhaust recirculation stream from the reactor; (d) cooling the recycle stream; (e) enter into the recirculating stream of additional monomer (s) to replace the polymerized monomer(s); (g) to re-enter the recirculation flow in the reactor and (C) removing from the reactor the polymer product.

Another variant embodiment of the invention relates to a continuous gas-phase or slurry process, preferably continuously triticosecale component, this process is carried out in the absence of a cleaning agent.

The preferred embodiment of the invention is a method for the continuous gas-phase polymerization of one or more olefins (individually or in combination) in the presence of a metallocene catalyst system on the media, and this process is carried out almost without a cleaning agent selected from the group comprising triethylamine, triisobutylaluminum, trimethylaluminum, etimani, diethylzinc and mixtures thereof.

Detailed description of the invention

Introduction

The present invention relates to a method of continuous polymerization, which is characterized by high efficiency and acceptable to obtain improved polymer products using metallocene catalyst component based on transition metal compounds with bulky ligand. It was found that the application of the cleansing component, which is usually used as an additive, in particular in the process of suspension and primarily gas-phase polymerization, in order to remove from the reactor impurities, increases the clogging and the formation of deposits that can lead to shutdown of the reactor. The cleansing is cleansing ingredients, which have a dual function. They not only remove impurities, but also serve as activators or socialization, primarily for traditional catalysts of the Ziegler-Natta, for example, of the halides of titanium and vanadium. In addition, the use of the cleansing component can cause a low-grade polymer product containing gels.

Moreover, too much cleansing agent can cause a decrease in catalytic activity and the formation of low molecular weight olefinic oligomers.

Therefore, eliminating or reducing the number of such well-known and widely used component as a purifying agent that provided by the method according to the present invention, allows to improve the health of the reactor, the improvement of catalytic activity and getting almost not containing gel polymer product.

Catalytic components and a catalytic system according to the invention

Metallocene catalysts generally represent, for example, such compounds of the transition metal with bulky ligand, which can be obtained from the products of formula: [L]mM[A]n,

where L denotes the volume of the ligand; ligand corresponds to the valency of the transition metal. In a preferred embodiment, the catalyst is chetyrehkratnym, so that the connection is able to ionize until the state of charge 1+.

The ligands L and A may be linked together by a bridge, and in the presence of two ligands L and/or A they can be connected by bridges. These metallocene compounds may be panasoniclumix compounds containing two or more ligand L, which can be a cyclopentadienyls ligands or ligands derived from cyclopentadiene, or polyangiaceae compounds comprising one ligand L, which is a cyclopentadienyls ligand or derivationally ligand.

In one embodiment, at least one ligand L contains many related atoms, preferably carbon atoms, and, as a rule, characterized by a cyclic structure, such as cyclopentadienyls ligand, which may be substituted or unsubstituted, or the same as a ligand derived from cyclopentadienyl, or such as any other ligand capable of education - 5-connection with the transition metal atom. One or more of these bulky ligands can be metal of group 4, 5 or 6, and/or metal from a number of lanthanides or actinides. With the transition metal can be linked with other ligands, such as tsepliaeva group, as, for example, hydrocarbon, hydrogen or any other univalent anionic ligand, but their list is not limited. Not limiting the scope of invention examples of metallocene catalysts and catalyst systems are described, for example, in U.S. patents 4530914, 4952716, 5124418, 4808561, 4897455, 5278264, 5278119, 5304614, all they are fully included in the present description as a reference. The same applies to European patent applications A-0129368, A-0591756, A-0520732, A-0420436, international applications 91/04257, 92/00333, 93/08221 and 93/08199, all of which are in full included in this description as a reference.

In the method of polymerization according to the present invention can be used catalytic system metallocene type different forms. Examples of the development of metallocene catalysts in the art for polymerization of ethylene is shown in U.S. patent 4871705, 4937299, 5324800, 5017714 and 5120867, all of which are in full included in this description as a reference. In these publications we are talking about the structure of metallocene catalysts and inclusion alumoxane in kakemega of the invention, examples of which are described in U.S. patents 4665208, 4952540, 5091352, 5206199, 5204419,4874734, 4924018, 4908463, 4968827, 5308815, 5329032, 5248801, 5235081, 5157137, 5103031, in the European applications A-0561476, B1-0279586, A-0594218 and in the international application 94/10180, all of which are included in the present description as a reference.

In addition, the metallocene catalyst component according to the invention can be a containing heteroatom mononitrobenzene connection. This heteroatom activate or alumoxanes, ionizing activator, Lewis acid, or their combination with obtaining the active polymerization catalyst system. The catalytic systems of these types are described, for example, in international applications 92/00333, 94/07928, 91/04257 and 94/03506, in U.S. patents 5057475, 5096867, 5055438, 5198401, 5227440 and 5264405 and in European patent application A-0420436, all of which are in full included in this description as a reference.

Moreover, metallocene catalysts, which can be used according to the present invention may include nasikabatrachidae catalytic components or ancillary ligands, such as broly and Carballeda, in combination with the transition metal. In addition, the scope of the present invention incorporated catalysts and catalytic systems that can, not only at the international applications 93/08221 and 93/08199 and European patent application A-0578838, all of which are included in the present description as a reference.

Preferred transition metals as catalyst components according to the invention are the metals of group 4, in particular zirconium, titanium and hafnium. Such transition metal may be in any oxidation state, preferably +3 or +4.

In the context of this description, the term "metallocene" refers to a compound containing one or more unsubstituted or substituted cyclopentadienyl or cyclopentadienyls residues in combination with the transition metal. In one embodiment, metallocene catalyst component corresponds to the General formula (Cp)mMRnR'pwhere at least one Cpdenotes unsubstituted or preferably substituted cyclopentadienyls ring, and substituted symmetrically or asymmetrically; M denotes a transition metal of group 4, 5 or 6; R and R' independently of one another denote halogen, hydrocarbonous group or hydrocarbonbearing group containing 1-20 carbon atoms, or a combination thereof; m is 1-3, n is 0-3 and p denotes 0-3, and the sum of m + n + p equals the oxidation state of M, preferably m oboznachaetto one of the formulas

(C5R'm)p, Rs(C5R'm)MQ3-p-x< / BR>
or

Rs(C5R'm)2MQ',

where M denotes a transition metal of group 4, 5 or 6, at least one of C5R'mdenotes a substituted cyclopentadienyl, each R', which may be identical or different, denotes hydrogen, alkyl, alkanniny, aryl, alcylaryl or arylalkyl radical containing 1-20 carbon atoms or two R' denote two carbon atom linked with the formation of part of a substituted or unsubstituted ring or rings containing 4-20 carbon atoms, R" denotes a radical containing one or more atoms or combinations of atoms selected from the group comprising atoms of carbon, germanium, silicon, phosphorous or nitrogen, and a connecting bridge two rings (C5R'mor a connecting bridge one ring (C5R'mwith M, when p represents 0, and x denotes 1, and in other cases, "x" is always equal to 0, each Q which can be identical or different, denotes aryl, alkyl, alkanniny, alcylaryl or arylalkyl radical containing 1-20 carbon atoms, halogen or alkoxide, Q' denotes alkylidene will radmacher 0, 1 or 2 and when s is 1, m is 4 and p denotes 1.

In the context of this description, the terms "socializaton" and "activators" are used interchangeably, and they refer to any compound or component which can activate the transition metal compound with bulky ligand or metallocene as defined above. Scope of the present invention includes the use of alumoxane as activator and/or to also use ionizing activators, neutral or ionic, or use of such metallogenic predecessors, as the three (n - butyl) ammoniates(pentafluorophenyl) boron or tripartition, which ionize the neutral metallocene compound. Such ionizing compounds may contain an active proton, or some other cation associated with the remaining ion of the ionizing compound, but not coordinated or only loosely coordinated with him.

Such compounds and the like are described in European applications A-0570982, A-0520732, A-0495375, A-0426637, A-0500944, A-0277003 and A0277004, in U.S. patents 5153157, 5198401, 5066741, 5206197 and 5241025 and in the application for U.S. patent 08/285380, filed August 3, 1994, all of which are in full included in this description as the Oia alumoxanes and ionizing activators (see, for example, international application 94/07928).

In another embodiment, the invention provides the possibility of combining in the catalytic system according to the invention two or more metallocene catalyst components. As examples of mixed catalysts described in U.S. patent 5281679, which is included in the present description by reference. In another embodiment, the invention also provides the possibility of combining at least one metallocene catalyst with demetallation catalyst or with a conventional catalyst or catalytic system of the Ziegler-Natta examples which do not limit the invention described in U.S. patent 4701432, 5124418, 5077255 and 5183867, all of which are included in the present description as a reference.

In the context of this description, the terms "media" and "substrate" are used interchangeably and refer to any material medium, preferably a porous carrier, such as talc, inorganic oxides, inorganic chlorides, in particular magnesium chloride, and retinoid media materials, such as polystyrene or politicaladministrative or other pouchitelnye materials carriers are inorganic oxide materials, which include those consisting of oxides of metals of groups 2, 3, 4, 5, 13 and 14 of the Periodic table of elements. In a preferred embodiment, the materials carriers for catalysts include silicon dioxide, aluminum oxide, kranidioti-aluminiumoxid and mixtures thereof. Other inorganic oxides that may be used either alone or in combination with silicon dioxide, aluminum oxide or kremmidiotis-aluminiumoxide include magnesium oxide, titanium dioxide, zirconium dioxide, etc.

In a preferred embodiment, the specific surface area of the carrier for the catalyst of the present invention is from about 10 to about 700 m2/g, the specific volume of its pores is in the range from about 0.1 to about 4.0 CC/g and the average size of the particles is from about 10 to about 500 microns. In a more preferred embodiment, the specific surface area is from about 50 to about 500 m2/g, specific pore volume is from about 0.5 to about 3.5 CC/g and average particle size is from about 20 to about 200 microns. In the most preferred embodiment, the specific surface area is from about 100 to about 400 m2/g, UD to about 100 microns. Typically, the pore size of the carrier according to the invention is preferably 10-1000 from 50 to about 500 and most preferably 75 to about 350

The catalytic system according to the invention can be prepared using a variety of techniques as described previously. In accordance with one variant of the catalyst is not applied to the carrier, as described, for example, in U.S. patent 5317036 and European patent application A-0593083, which are included in the present description as a reference. In a preferred embodiment of the invention the catalytic system is applied to the carrier. Examples of application to the carrier catalyst system used according to the invention described in U.S. patent 4937217, 4912075, 4935397, 4937301, 4914253, 5008228, 5086025, 5147949, 4808561, 4897455, 4701432,5238892, 5240894 and 5332706, in international applications 95/10542, published April 20, 1995, 95/07939, published March 3, 1995, 94/26793, published on 24 November 1994, and 95/12622, published may 11, 1995

In one embodiment of the method according to the invention prior to the main polymerization of olefin(s), preferably C2-C20-alpha-olefins, more preferably ethylene, propylene or combinations thereof, pre-polymerized in the presence of a catalyst or kataliticheski, in solution or in suspension, including the application of high pressure. Terpolymerization can be performed using any alpha-olefin monomers, or combinations thereof and/or in the presence of any agent of regulating the molecular weight, such as hydrogen. In more detail terpolymerization described in U.S. patent 4923833, 5283278 and 4921825 and in European patent application B-0279863, all of which are in full included in this description as a reference.

In another embodiment, a catalytic system on the media include antistatics, such as described in U.S. patent 5283278, which fully included in the present description by reference. Examples of antistatic agents, do not limit the invention include alcohols, thiols, silanol, diols, esters, ketones, aldehydes, acids, amines and ethers. Preferred tertiary amines, ethoxylated amines and polyether compounds. Such an antistatic agent can be added at any stage of the process of preparation of the catalytic system on the media according to the invention, however, preferably be added after preparation of the catalytic system on the media according to the invention either in the form of sludge or dried in the finding includes a polyolefin wax, agent for improving adhesiveness or etc.

A preferred variant of the method of preparation of the catalyst according to the invention are described below and can be found in the patent applications U.S. 265533 filed June 24, 1994, and 265532, filed June 24, 1994, both complete applications included in the present description as a reference. In a preferred embodiment, metallocene catalyst component is typically suspended in a liquid receiving metallocene solution and preparing a separate solution containing the activator and a liquid. As this liquid you can use any compatible solvent or other liquid capable of forming a solution or similar with at least one metallocene catalyst component and/or at least one activator. In a preferred embodiment, the fluid is a cyclic aliphatic or aromatic hydrocarbon, most preferably toluene. Metallocene and activator solutions are preferably blended and add to the porous carrier so that the total volume of the metallocene solution and the activator solution or the solution metallocene and the reactor was less than four times the pore volume of the pores is more preferably so it was 1-1,5 - to 2.5-4-fold and most preferably 1.5 to 3-fold volume of porous media. Also in the preferred embodiment, the preparation of the catalyst type antistatic agent.

In one of the preferred variants of the invention provides for the application of almost homogeneous catalytic systems. In the context of this description and in the accompanying claims, the term "almost homogeneous catalyst" means a catalyst, in which the molar content of the transition metal catalytic component, preferably together with an activator, is the same in all porous media.

Methodology to measure the total volume of pores of porous media are well known in the art. Detail one of such techniques are described in volume 1 of the works of Experimental Methods in Catalytic Research (Academic Press, 1968), where special attention should be paid to pages 67-96. This preferred method includes the use of the classic BAT-device for absorption of nitrogen. Another method well known in the art, described by Innes in Total Porosity and Particle Density of Fluid Catalysts by Liquid Titration, volume 28, N 3, Analytical Chemistry 332-334 (March, 1956).

The molar ratio between the metal activator most preferably 50:1-500:1. When the activator is an ionizing activator, which is described above, the preferred molar ratio between the metal of the activator component and the transition metal metallocene component is 0.3:1-3:1.

The method of polymerization according to the invention

Catalysts and catalytic systems of the present invention is suitable for polymerization of the monomers and optional comonomers in any polymerization process is a gas phase or in suspension; the most preferred gas-phase process.

In a preferred embodiment, the invention relates to suspension and gas-phase reactions of polymerization and copolymerization, including the polymerization of one or more alpha-olefin monomers containing 2 to 20 carbon atoms, preferably 2-12 carbon atoms. The present invention is most appropriate to use when carrying out the copolymerization reactions involving the polymerization of one or more monomers, for example alpha-olefin monomers as ethylene, propylene, butene-1, penten-1, 4-methylpentene-1, hexene-1, octene-1, mission-1, and cyclic olefins, such as cyclopentene and styrene, and combinations thereof. Other monomers can include polarly monomers. It is preferable to obtain a copolymer of ethylene or propylene. The preferred co monomer is an alpha olefin containing 3 to 15 carbon atoms, preferably 4-12 carbon atoms and most preferably 4-10 carbon atoms. In accordance with another variant of ethylene or propylene will polimerizuet together at least two different comonomers to obtain ternary copolymer, etc.; the preferred comonomers are combinations of alpha-olefin monomers containing 3-10 carbon atoms, more preferably 4-8 carbon atoms.

Alternatively, the ethylene or propylene will polimerizuet together at least two different comonomers to obtain ternary copolymer, etc.; the preferred comonomers are combinations of alpha-olefin monomers containing 3-10 carbon atoms, more preferably 3-8 carbon atoms, optionally at least one diene monomer. Preferred ternary copolymers include such combinations as copolymers of ethylene/butene-1/hexene-1, ethylene/propylene/butene-1, propylene/ethylene/butene-1, propylene/ethylene/hexene-1, ethylene/propylene/norbornadiene etc.

As a rule, in prikolinyi gas stream, also known as a recycle stream or pseudozyma environment, is heated in the reactor by the heat of polymerization. Such heat away in another part of the cycle with a cooling system outside the reactor (see, for example, U.S. patents 4543399, 4588790, 5028670, 5352749, 5405922 and 5436304, all of which are in full included in this description as a reference).

Typically, in gas-phase process with fluidized bed upon receipt of the polymer from monomers gaseous stream containing one or more monomers in the reaction conditions is continuously circulated through a fluidized bed in the presence of a catalyst. This gaseous stream is removed from the fluidized bed and return to the reactor. At the same time from the reactor assign the polymer product and to replace the polymerized monomer or add a new fresh monomer.

The process of suspension polymerization is usually carried out under pressure in the range of from about 1 to about 50 atmospheres and even greater and the temperature is from 0 to about 200oC. In the process of suspension polymerization in a liquid polymerization medium, which is injected ethylene and comonomers and often hydrogen together with a catalyst, formed suspension tnat alkane or cycloalkane or aromatic hydrocarbon, such as toluene, ethylbenzene or xylene. The medium used in the polymerization conditions should be a liquid and to be relatively inert. It is preferable to use hexane or isobutane. Examples of slurry processes do not limit the invention include processes in the reactor with circulation or with a mixer.

In one embodiment, the performance of the reactor used according to the present invention, ranges from more than 500 lbs/HR (227 kg/HR) to about 200,000 lbs/HR (90900 kg/HR) or higher of polymer, preferably more than 1000 lbs/HR (455 kg/HR), more preferably more than 10,000 lbs/HR (4540 kg/HR), even more preferably more than 25,000 lbs/HR (11300 kg/h), mainly over 35,000 lbs/HR (15900 kg/h), even more preferably more than 50,000 lb/h (22700 kg/HR) and most preferably from more than 65,000 lbs/HR (29000 kg/h) to more than 100,000 lb/h (45500 kg/h).

In another embodiment of the method according to the invention receive more than 1000 pounds (455 kg) of polymer product per hour, preferably more than 10,000 pounds (4540 kg) of polymer product per hour, most preferably more than 50,000 pounds (22700 kg) of polymer product per hour.

In the context of this description and in prilagaemom to interact with oxygen and/or water and/or polar compounds and which does not contain the catalytic components, for example, the metallocene catalyst component, activator, and an optional carrier, or components remaining in the catalyst or the catalyst used in its preparation, for example, toluene, containing any of the ORGANOMETALLIC compound used in the preparation of the catalyst. Examples of cleaning agents, do not limit the invention are those that can be represented by the General formula RnA, where A denotes an element of group 12 or 13, and each R, which may be identical or different, denotes a substituted or unsubstituted remotemachine or branched alkyl radical, cyclic hydrocarbonyl radical, alkylcyclohexanes radical, aromatic radical or alkoxy radical and n denotes 2 or 3.

In accordance with another variant of the cleansing agent is aluminiumindustrie compound of the formula AlR(3-a)Xawhere R denotes alkyl, cycloalkyl, aryl, or hydride radical. Each alkyl radical can be remotemachine or branched chain containing 1-20 carbon atoms, preferably 1-10 carbon atoms. X denotes halogen is useprivatekey the formula M represents aluminum (Al), as illustrative, and not limiting the scope of the invention examples of such compounds can be called trialkylaluminium compounds such as trimethylaluminum, triethylaluminum, tri-n-Propylamine, triisopropanolamine, tri-n-butylamine, three-second-butylamine, three-tert-butylamine, triisobutylaluminum, tri-n - pentylamine, tricyclopentadiene, tri-n-hexylamine, three(4-methylpentyl)aluminum, three(3-methylpentyl)aluminum, tricyclohexylphosphine etc.; aluminiumgie, such as dimethylethylamine, methyldiethylamine, ethyldimethylamine, dimethyl-n-Propylamine, methyldi-n-propylalanine, dimethylethanolamine, dimethylcyclohexylamine, methylethylenediamine etc., aryl - and alkyl substituted aluminum compounds, such as triphenylamine, three-pair-tolylamino, three meta-tolylamino, three-pair-ethylamine etc.

Other not limit the invention to the examples of typical cleansing agents include dialkylaminoalkyl, in particular diethylacetanilide, ethylaminoethanol, -bromides and iodides, as well as dialkylaminoalkyl, -bromides and iodides; aluminiumoxide and-aryloxy, such as diethylaminoethylcellulose-4-methylphenoxy, dimethylamino-3 - methylphenoxy, dimethylamino-2,6-diisopropylphenol, dimethylamino-2,6-di-tert-butyl-4-methylphenoxy etc.

Similarly, the list of typical compounds of elements of group 13, in which M represents boron, may include trialkylborane, alkylborane and alkylpolyglycoside. In addition, a similar list can be similar to the compounds of gallium and indium. This list is almost identical to the list above for aluminium-containing materials, therefore, in the present description, such a list of similar Baranov and similar compounds of other elements in group 13 are omitted.

Generally, the preferred cleaning agents are those in which in the formula above, M represents aluminum or boron. Of aluminium-containing variants of compounds of elements of group 13 as cleansing agents most often used trialkylaluminium connection, and most preferred from trialkylaluminium compounds are triethylaluminum, triisobutylaluminum and trimethylaluminum.

As other specific examples of cleaning agents include ORGANOMETALLIC compound BX3in which X hereafter shall mean hydrocarbon group, which may be the same or different.

Other ORGANOMETALLIC compounds which can be used as cleansing agents include ORGANOMETALLIC alkali, alkoxides and halides of metals of groups 1, 2, 3 and 4. Preferred ORGANOMETALLIC compounds are liteally, magnesium - or cancelkey, maniackiller, aluminiumgie, cranially, cranialsacral and kremnicaslovakia. Preferred ORGANOMETALLIC compounds that can be used as cleansing agents are aluminiumgie and maniacly. The most preferred ORGANOMETALLIC compounds that can be used as cleansing agents are aluminiumgie, such as triethylaluminium (TEAL), trimethylaluminum (TMAL), triisobutylaluminum (TIBAL) and tri-n - hexylamine (TNHAL) and diethylaluminium (DEAH), etc., and the most widely used cleaning agent is TEAL.

In one embodiment of the method according to the invention the process is carried out in the practical absence of a cleansing agent. In the context of this description and in the accompanying claims those who t time the contents of the cleaning agent is not more than 10 ppm million of the total weight of the recirculation flow.

In another embodiment of the method according to the invention the process is carried out essentially without a cleaning agent. In the context of this description and in the accompanying claims, the term "essentially no" means that the implementation of the method according to the invention at any given point in time the contents of the cleaning agent is not more than 50 ppm million of the total weight of the fluidized bed.

In one embodiment of the method according to the invention the content of the purifying agent in the reactor is less than 30 ppm million, preferably less than 20 ppm million, more preferably less than 10 ppm million and most preferably 0-15 frequent./million

In one embodiment, at the beginning of the operation of the reactor to remove impurities and to provide initiation of polymerization cleansing agent is used in amount less than 300 ppm million, preferably less than 250 ppm million, more preferably less than 200 ppm million, even more preferably less than 150 ppm million, more preferably less than 100 ppm million and most preferably less than 50 ppm million of the total weight of the fluidized bed within the first 12 hours from the moment of introducing the catalyst into the reactor, preferably within 6 hours, more predpoctenie 1 h, then the supply of cleaning agent cease.

In another embodiment of the method according to the invention the cleaning agent is contained in a quantity sufficient to ensure that the catalyst according to the invention has achieved the catalytic performance component in terms of weight of more than 1000 grams of polymer per gram of catalyst, preferably more than about 1500, more preferably more than 2000, more preferably more than 2500, and most preferably more than 3000.

In yet another embodiment of the method according to the invention at the initial stage of the cleaning agent is contained in a quantity sufficient to ensure that the catalyst according to the invention has achieved the catalytic performance in 40 percent of the productivity in a stationary mode, preferably less than 30%, even more preferably less than 20% and most preferably less than 10 percent. In the context of this description and in the accompanying claims, the term "fixed mode corresponds to a normal performance, i.e., the weight of polymer obtained per hour.

The performance of the catalyst or catalytic system is influenced by the partial pressure is nomera - ethylene or propylene is from about 25 to 90 mole percent, and the absolute partial pressure of the monomer is from about 75 (517 kPa) to about 300 psig, which corresponds to the typical conditions of the gas-phase polymerization process.

If in the method according to the invention using a cleansing agent, this cleansing agent, as a rule, you can enter into the reactor directly or indirectly in the recycle stream or any external device for inputting a cleaning agent into the reactor. In a preferred embodiment, in a typical gas-phase process, the cleaning agent is introduced into the reactor directly, and most preferably directly in the reactor layer or below the distribution plate, preferably after reducing layer in the fluidized state. In one embodiment, this cleaning agent can be introduced in the reaction system as a whole, individual portions or continuously.

The cleaning agent used in the method according to the invention, is introduced into the reactor with a flow rate equivalent to 10-100 ppm million in terms of performance in a stationary mode, after which the supply of cleaning agent cease.

In accordance with the Finance, enter in sufficient quantity to provide improved catalytic performance in terms of weight to a level of 200 g of polymer per gram of catalyst per minute, preferably at the level of 300, even more preferably at 400 and most preferably at a level of 500.

In another embodiment, the molar ratio between the metal cleaning agent and the transition metal metallocene catalyst component is equal to approximately 0.2 times the quantity of cleansing agent, expressed in frequent./million in terms of performance, and multiplied by the catalytic performance, expressed in kilograms of polymer per gram of catalyst. The interval of values of the molar ratio is from about 300 to 10. In a preferred embodiment, in which as a cleansing agent use aluminiuim, this molar ratio corresponds to the ratio between aluminum (Al) and the transition metal, for example, zirconium, where the molar content of Al is correlated with the total number of used cleaning agent.

In a preferred embodiment, the hydrogen in the system is not administered simultaneously with a cleaning agent. Under the crust is Italia, which is used for the introduction of a metallocene catalyst system.

It was found that the fouling is influenced by the presence of initially volatile low molecular weight olefin oligomers. These oligomers are usually a substance whose molecules contain an even number of carbon atoms, a molecular weight of less than 1000 and the share of which in the polymer is not more than 1 wt.%. Hydrocarbon oligomers containing up to about 30 carbon atoms can be identified by known in the art methods using tabledescription installation with a short trajectory model TD-2 by Scientific Instrument Services, Ringos, PCs new Jersey, coupled with a gas chromatograph Hewlett-Packard 5890, equipped with a capillary column to boiling point (DB-5) and mass-selective detector Hewlett-Packard 5970. As a method of determining use a simple method of measuring olefinic fraction in wt.%.

In one embodiment, the value of the ratio between the weight percentages of olefin oligomers and the weight percentages of aliphatic oligomers, which determine in the polymer product must be in the range from about 0 to primer predpochtitelno from about 0 to about 5.

It was found that reducing the number of cleaning agent introduced into the reactor equipment, which includes the reactor and its external systems and pipelines, can significantly reduce the total number of the resulting olefinic or unsaturated oligomers in combination with some decrease in the number of aliphatic or saturated oligomers.

In one embodiment of the invention, the process preferably gas-phase process is conducted in such a way that in the resulting polymer product weight fraction of olefinic hydrocarbon oligomers with number of carbon atoms less than or equal to 30 is less than 0.06.

According to the present invention provides the possibility of using installed outside of the reactor system is removed from the recirculating stream of cleansing agents, introduced during implementation of the method according to the invention, or the ability to handle pseudoviruses environment to remove the cleaning agent (see , for example, U.S. patent 4460755 included in the present description by reference).

Alternatively the cleaning agent is injected in such a quantity which is sufficient to ensure that the total content of unsaturated C30- who was less than 50 frequent. per million, preferably less than 40 or 30 frequent. per million, more preferably less than 20 ppm million and most preferably less than 10 ppm million

In the context of this description and in the accompanying claims under the small particles refers to polymer particles with sizes less than 125 microns (of 0.0125 cm). The content of fine particles of this size can be determined using a standard installation with a sieve for sifting with a cell size of 120 mesh. In a preferred embodiment of the method according to the invention the quantity of the purifying agent in the reactor at any given time, must be such that the content of small particles with sizes less than 125 microns (of 0.0125 cm) was less than 10%, preferably less than 1%, more preferably less than 0.85% to less than 0.05%.

According to the present invention provides the possibility of using installed outside of the reactor system is removed from the recirculating stream of cleansing agents, introduced during implementation of the method according to the invention. This would prevent the return of the cleansing agent in the reactor and to prevent the accumulation of cleansing agent in the reactor system. In a preferred embodiment, such a system is placed IU cleansing agent is generated by condensation from passing through the recirculation flow pseudoviruses environment. It would be preferable to expose this pseudovirus environment processing to remove the cleaning agent (see, for example, U.S. patent 4460755 included in the present description by reference).

In the method according to the invention also provides for the possibility of intermittent introduction of the cleaning agent during the process, in which the recirculation flow removes more than 90%, preferably more than 95% of all entered a cleaning agent.

According to the present invention assumes use at the initial stage of catalyst, catalyst system or its components according to the invention as a cleaning agent, but this would have led to a significant appreciation of the process.

Conducted in accordance with the preferred mode of carrying out the invention process is a gas phase polymerization process in a condensed version. In the context of this description and in the accompanying claims, the term "condensed version" refers to the process of gas-phase polymerization carried out targeted fed into the reactor recirculation stream containing liquid and gas phase, so that the weights is about 2.0 wt%.

In one embodiment of the method according to the invention the weight fraction of liquid in the recirculation flow from the total weight amount of the recirculation stream is from about 2 to about 50 weight percent, preferably 10 weight percent, more preferably more than 15 weight percent, even more preferably greater than 20 weight percent and most preferably is from about 20 to about 40 percent. However, depending on the desired performance of the condensed phase can be used in any relative amount.

In accordance with another embodiment of the method according to the invention the number of used cleaning agent, if used, must match the value of the molar ratio is less than 100, preferably less than 50, more preferably less than about 25, where the mean molar ratio between the metal cleaning agent to the transition metal and the transition metal metallocene, and, when the cleaning agent is an aluminium-containing ORGANOMETALLIC compound and the transition metal metallocene is a metal of group 4, the above molar

"Fouling" is a term used to describe the accumulation of polymer deposits on the surfaces of the reactor. Fouling is a negative phenomenon, affecting all types of equipment polymerization process, including the reactor and associated components, accessories, etc. Fouling is the most negative impact on areas of narrowing the gas stream or a liquid stream. The two main areas that are more susceptible to fouling are the heat exchanger and the distribution plate. The heat exchanger consists of a series of tubes of small diameter, grouped in a bunch. Distribution plate is a solid plate, which includes a number of holes of small diameter, providing a passage through them is contained in the recirculating gas stream before it enters into the reaction zone or distribution in the layer of solid polymer in the reactor with a fluidized bed, for example, such as described in U.S. patent 4933149 included in the present description by reference.

Fouling is evident in the increase in pressure drop when passing through either the plate or the fridge, or in either case, what Asa effective circulation through the compressor, and often the operation of the reactor must be stopped. The cleaning of the reactor can use a few days, and it is associated with a lot of time and is expensive. Clogging also affected piping for circulating gas and the compressor, however, usually occurs fouling plates and refrigerator.

For the quantitative determination of the rate of fouling is expedient to determine the fouling factor F. F denotes the fraction of the cross section of the hole, which is blocked by deposits. If F=0 (0%), fouling does not occur. Conversely, if F=1 (100%), the hole fully scored. Fouling can be associated with the differential pressure P, at this point in time, the differential pressure in clean system defined as P0. With increasing fouling P increases, exceeding the initial pressure difference P0. F is obtained from the following expressions:

(I) the Fouling plates

< / BR>
(II) Fouling of the refrigerator

< / BR>
Usually, when F is in the range from more than about 0.3 to about 0.4 (30-40%), stopping operation of the reactor is inevitable. In a preferred embodiment, F is less than 40%, preferably less than 30%, even more preferably less than 20%, mostly less than 15%, and most the technology for the quantitative determination of fouling. If no fouling does not occur, then the rate of fouling is equal to zero. The maximum rate of growth for the industrial process is approximately 12 percent per month, or 0.4 percent/day, preferably less than 0.3%/day, even more preferably less than 0.2%/day and most preferably less than 0.1%/day.

Examples

Below to explain its essence the present invention, including its characteristic advantages and volume, illustrated with examples.

The properties of the polymer was determined using the following test methods.

The melt index was measured in accordance with ASTM D-1238, condition E.

The density was measured in accordance with ASTM D-1238.

Volumetric weight was measured as follows: the resin was filled through a funnel with a diameter of 7/8 inch in the cylinder fixed volume of 400 cubic cm; body weight was determined as the weight of resin in the cylinder divided by 400 CC, receiving the amount in grams per cubic centimeter.

The size of the particles was determined as follows: the particle size was measured by determining the weight of material collected on the standard U.S. sieve, and determine the x through a standard sieve with mesh size of 120 mesh, of the total amount of material.

Comparative example 1

In this example, the described process is carried out using metallocene catalyst based on bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect of fouling during operation of an industrial reactor using TEAL. This example contains information since the beginning of the industrial reactor with a metallocene catalyst.

Preparation of catalyst

The metallocene catalyst was prepared using silica dehydrated at 600oC. This catalyst was a technical catalyst prepared in the mixer with the mixer. In the mixer was loaded initial portion 1156 pounds (462 kg) of toluene. Then have entangled 925 pounds (421 kg) solution methylalumoxane in toluene with a concentration of 30 weight percent. Next I put 100 pounds (46 kg) of a solution of bis(1,3-methyl-n - butylcyclopentadienyl)zirconiated in toluene with a concentration of 20 weight percent [content metallocene 20.4 lb (9.3 kg)]. After washing the cylinder from under added metallocene and to ensure the mixture for 30 min under normal conditions in swale, namely, the solution of the surface modifier containing 5.3 lb (2.4 kg) product AS-990. Additional serving per 100 pounds (46 kg) of toluene was washed container from under the surface modifier was added to the mixer. The resulting suspension was dried in vacuum under an absolute pressure of 3.2 lb/sq inch (70,6 kPa) at 175oF (79oC) obtaining engineering powder. The weight of the finished catalyst was 1093 lb (497 kg). The final content of zirconium in the catalyst amounted to 0.40% and the aluminum content was equal to 12.0%.

Polymerization

The polymerization was carried out in gas-phase reactor industrial type of continuous fluidized bed. Fluidized bed formed from polymer granules. Gaseous streams source of ethylene and hydrogen was introduced below the working layer of the reactor in the gas recirculation line. Below the working layer of the reactor through a separate line in-line recirculation gas filed hexenoic comonomer. Along the line of the recirculation gas in the reactor was also administered an inert hydrocarbon such as isopentane. The isopentane was added to give the reactor recirculation gases additional heat. To maintain a constant target sostavleniya between hydrogen and ethylene regulate the concentration of ethylene. The gas concentration was measured using installed on the production line gas chromatograph, which ensured the relative constancy of the composition of the recirculated gas stream. Above the distribution plate for fluidized bed directly in the fluidized bed have introduced triethylaluminium (TEAL) in the form of a solution in isopentane concentration of 20 weight percent.

The solid catalyst was injected directly into the fluidized bed using purified nitrogen. To maintain constant flow regulating the flow of catalyst. The reaction layer of the growing polymer particles maintained in a fluidized state by a constant flow of raw materials and the recirculation gas passing through the reaction zone. The reactor was operated under a total pressure of 310 psi (2138 kPa). To maintain a constant temperature in the reactor the temperature of the recirculation gas is constantly regulated by raising or lowering in accordance with changes in the speed of heat in the polymerization.

The height of the fluidized bed was maintained at a constant level by removing the part of this layer with a flow rate equal to the volumetric velocity of the cell volume. Gas from these cameras fixed volume was returned to the reactor with the aid of the compressor for recirculation gas, which was recuperavel reactor gases. The product was transferred to a purge vessel to remove trapped hydrocarbons and was treated with humidified nitrogen for decontamination of residual catalyst.

Experimental results

The following describes the conditions of the experiment, which illustrates the fouling in industrial gas-phase reactor (PL. 1, 2). This experiment was carried out since the beginning of the reactor operation, i.e. when the reaction has not started yet. During the experiment, the reactor was continuously introduced TEAL. The experiment lasted for 18 hours, after which it was completed due to fouling of the distribution plate in the reactor and refrigerator.

Comparative example 2

In this example, described the work of the pilot reactor when using a metallocene catalyst based on bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect on fouling of process conditions at two different temperatures in the case of using the same catalyst as that described to enter is the iMER 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed. Fluidized bed formed from polymer granules. Gaseous streams source of ethylene and hydrogen together with liquid co monomer were mixed together in the branch device and introduced below the working layer of the reactor in the gas recirculation line. As co monomer used hexene. With this stream was mixed triethylaluminium (TEAL) in a 1 wt.%-aqueous solution in isopentane used as a solvent carrier. To maintain a constant target of the composition of the regulated consumption of individual streams of ethylene, hydrogen and co monomer. To maintain a constant partial pressure of ethylene was adjusted to the concentration of ethylene. To maintain a constant molar ratio between hydrogen and ethylene regulate the flow rate of hydrogen. Concentration of all the gases was measured using installed on the production line gas chromatograph, which ensured the relative constancy of the composition of the recirculated gas stream.

The solid catalyst was injected directly into the fluidized bed using purified nitrogen is a promotional layer of growing polymer particles maintained in a fluidized state by a constant flow of raw materials and the recirculation gas, passing through the reaction zone. To achieve this, the velocity of the gas was maintained at a level of 1-3 m/C. the Reactor was operated under a total pressure of 300 pounds per square inch. To maintain a constant temperature in the reactor the temperature of the recirculation gas is constantly regulated by raising or lowering in accordance with any changes in the speed of heat in the polymerization.

The height of the fluidized bed was maintained at a constant level by removing the part of this layer with a flow rate equal to the volumetric rate of production of the powdered product. The semi-continuous product was removed through a series of valves in the chamber of fixed volume, the gases from which are simultaneously returned to the reactor. This gave an opportunity with high efficiency to remove the product, at the same time returning a substantial portion of the unreacted gases back to the reactor. This product was purged to remove trapped hydrocarbons and treated weak current humidified nitrogen for decontamination of all traces of residual catalyst.

Results

The reactor is in a stationary mode was obtained ethylene-hexenoic copolymer with melt index of 1 and a density of 0,917. Experime speed fouling as refrigerator, and plates, which significantly exceeded the speed limit of 0.4%/day. With increasing temperature the rate of fouling increased.

Comparative example 3

In this example, described the work of the pilot reactor when using a metallocene catalyst based on bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect on fouling of process conditions at two different temperatures in the case of using the same catalyst as described above. The process was carried out at higher than in example 2, a partial pressure of ethylene.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor is in a stationary mode was obtained ethylene-hexenoic copolymer with melt index of 1 and a density of 0,917. The experiment was performed under the conditions shown in table. 3.

The results obtained indicate a high rate of abrasca the temperature is increased the rate of fouling was increased. On the rate of fouling of the fridge partial pressure of ethylene had no effect, but if you compare with example 2, when a higher concentration of ethylene speed fouling plates increased.

Example 4

In this example, described the work of the pilot reactor when using a metallocene catalyst based on bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect on fouling of process conditions at a lower concentration TEAL.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor is in a stationary mode was obtained ethylene-hexenoic copolymer with melt index of 1 and a density of 0,917. The experiment was performed under the conditions shown in table. 4.

The results obtained indicate a reduced rate of fouling a fridge and plates compared with the rate in example 3. However, it is still significantly exceeded Maxim is ornago installation when using a metallocene catalyst based on bis(1,3 - methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect on fouling of process conditions at zero concentration TEAL.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor is in a stationary mode received hexenoic copolymer with melt index of 1 and a density of 0,917. The experiment was performed under the conditions shown in table. 5.

The obtained results confirm that the rate of fouling as a refrigerator, and dish was the lowest compared with the rate in the previous examples. However, it still exceeded the speed limit of 0.4%/day. This is due to the fact that all the experiments in examples 2-5 were carried out in the same polymerization mode. Results in the absence of aluminiumgie received at the end of the experiment after heavy fouling of the reactor. Considering this is a pretty serious limitation, this result suggests that the rate of fouling was not menari using a metallocene catalyst based on bis (1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect on fouling of process conditions at zero concentration TEAL. The reactor was started using TEAL, which was quickly deleted after a few hours of the process. The operating conditions of the reactor was chosen in order to compare them with the conditions for the case of the high rate of fouling (see example 3).

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor is in a stationary mode received hexenoic copolymer with melt index of 1 and a density of 0,917. The experiment was performed under the conditions shown in table. 6.

The obtained results confirm that the rate of fouling as a refrigerator, and dish was the smallest of all the conducted experiments. The rate of fouling was significantly lower than the maximum speed of 0.4%/day. At the end of this experiment, the reactor was opened and inspected. When checking as plates, so the PR contained massive accumulation of polymer in the refrigerator, and on the plate.

Example 7

In this example, described the work of the pilot reactor when using a metallocene catalyst based on bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect of using aluminiumgie during the beginning of the reactor operation. Used trimethylaluminum (TMA) as a more volatile and reactive aluminiuim.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor for several hours was blown under pressure to remove all residual oxygen and moisture. In the reactor were created the conditions specified in the table. 7. The reactor was pre-treated with 150 weight.frequent. /million TMA.

TMA in the reactor did not enter. Started the flow of catalyst. It was administered continuously with increasing flow rate for five hours. At this stage, with a flow rate of 150 CC/h was introduced by the TMA solution in isopentane. After 60 min began to dovalidate. Resumed the supply of TMA and the newly initiated an uncontrolled reaction. This "pulsating flow" TMA continued for several hours until, until the reaction began to occur spontaneously without TMA.

Example 8

In this example, described the work of the pilot reactor when using a metallocene catalyst based on bis (1,3 - methyl-n-butylcyclopentadienyl)zirconiated. In this experiment illustrates the effect of using aluminiumgie during the beginning of the reactor operation. This experiment confirmed that the deadline for aluminiumgie simultaneously retains catalytic activity.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor for several hours was blown under pressure to remove all residual oxygen and moisture. In the reactor were created the conditions specified in the table. 8. This reactor cleaning agent is not pre-processed.

TEAL ate concentrations together with the catalyst. Immediately upon introduction of the catalyst was noted the course of the reaction. Filing TEAL continued until, until it reaches 25% of the estimated performance. Further submission TEAL was stopped and the reaction continued to proceed to achieve full performance. TEAL was introduced with the catalyst in total within 95 minutes. Full speed reaction was achieved in the absence of TEAL after four hours.

The obtained result confirms the influence of a cleaning agent, in this case aluminiumgie, to initiate the reaction. This result confirms the possibility of removal TEAL while maintaining the reaction after its initiation.

Example 9

In examples 9A-9D illustrate the effect of the concentration TEAL in a batch reactor, the steps for the suspension polymerization activity of metallocene catalyst. All the polymerization processes carried out by the method described below using the appropriate number of TEAL specified in table 1 for each example.

Preparation of catalyst

A 2-gallon reactor was initially loaded with 1.1 l of toluene, and then 0,93 l of a solution of MAO in toluene concentration of 30 wt.%, post-aqueous solution in toluene. This mixture was stirred for 30 min at room temperature, after which the fluid under careful stirring was added 350 g of silica (Davison MS948, dehydrated at 600oC). The mixing speed was increased approximately 10 minutes to provide a dispersion of silicon dioxide in the liquid, and then with careful stirring 2 portions 175 g liquid was added an additional amount of silicon dioxide, with the consequent increase of the stirring speed. After introduction into the reactor of the total number of silicon dioxide (700 g) was added 0.6 l of toluene, obtaining the suspension with a consistency from liquid to solid, containing silicon dioxide in a concentration of 4 CC/g, the Stirring was continued for 15 min with a speed of 120 rpm, after which it was dissolved 5 g of the surface modifier (supplied on the market by the company Witco Chemical Corporation, Houston, pc. Texas) in 100 CC of toluene, was added to the resulting solution and was stirred for 15 minutes Then held vacuum drying by blowing some N2at 175oF (79,4oC). When the appearance of the catalyst was engineering, it was cooled and unloaded in a nitrogen purged vessel. When this reached the exit of the dry catalyst is that downloaded the appropriate number of triethylaluminum (TEAL), and then 60 CC of 1-hexene as co monomer and 800 CC of isobutane diluent. The contents of the reactor were heated to 80oC, and then were injected with 100 mg of the catalyst simultaneously with ethylene, which served to create in the reactor total gauge pressure of 325 psig (2241 kPa). The temperature in the reactor was maintained at a level of 85oC for 40 min was performed polymerization. After 40 min, the reactor was cooled, ethylene dumped into the atmosphere, and the polymer was dried and weighed to determine yield. Data output and activity are presented in table.9.

Because the cleansing agent is TEAL, and transition metal metallocene is zirconium (Zr), the molar ratio for this table is expressed as an Al:Zr.

The above example 9 shows that to remove impurities in the polymerization reactor in this example was necessary to create a certain concentration of a cleaning agent. When exceeding a certain concentration of the purifying agent acts as a catalytic poison, which is evident in the decrease of activity.

Example 10

In this example, described the work of the pilot reactor using metallopolimerov influence of the lack TEAL in the implementation of the method according to the invention on the quality of the film, reflecting on the content of the gel films made by the method according to the invention. Gels called the prisoners in the film is small, highly visible areas that typically contain heavier and/or more high-density materials in comparison with the basic polymer.

Preparation of catalyst

The metallocene catalyst was identical to the catalyst of example 1.

Polymerization

Polymerization (experiments 1A and 1B) were carried out in gas-phase reactor of continuous fluidized bed as in example 2.

Results

The reactor is in a stationary mode was obtained ethylene-hexenoic copolymer with melt index of 1 and a density of 0,917. The experiment was performed under the conditions shown in table. 10.

The film of experiment 1B essentially did not contain inclusions, whereas the film of experiment 1A contained a substantial number of small inclusions, in appearance resembling sandpaper. The film, which, as a rule, can be used in the technique, contain only a small number of gels. In this example, a film was made of the polymer obtained in the reactor using TEAL in cachestate from the state, which was peculiar technically unsuitable film, to the state, which is typical for a film with excellent transparency, primarily intended for use in the form of a stretchable films.

Examples 11-16

Preparation of catalyst

The metallocene catalyst was prepared using 800 pounds (364 kg) of silica (Davison 948), dehydrated at 600oC. This catalyst was a technical catalyst prepared in the mixer with the mixer. In this mixer was loaded initial portion 1156 lbs (525 kg) of toluene. Then have entangled 925 lbs (420 kg) of a solution methylalumoxane in toluene with a concentration of 30 weight percent. Next added 100 pounds (46 kg) of a solution of bis(1,3-methyl-n-butylcyclopentadienyl)zirconiated in toluene with a concentration of 20 weight percent [content metallocene 20.4 lb (9.3 kg)]. After washing the cylinder from under added metallocene and to ensure the mixture for 30 min under normal conditions in the mixer was added additionally 144 lbs (66 kg) of toluene. The above mixture was added to the silica, after which he entered 54.3 lb (25 kg) product Kemamine AS-990 in toluene, namely the solution of the modifier to the surface of container from under the surface modifier was added to the mixer. The resulting suspension was dried in vacuum under an absolute pressure of 3.2 lb/sq inch (70,6 kPa) at 175oF (79oC) obtaining engineering powder. The weight of the finished catalyst was 1093 lb (497 kg). The final content of zirconium in the catalyst amounted to 0.40% and the aluminum content was equal to 12.0%.

Polymerization

The polymerization was carried out in gas-phase reactor of continuous fluidized bed. This fluidized bed formed from polymer granules. Gaseous streams source of ethylene and hydrogen together with liquid co monomer were mixed together in the branch device and introduced below the working layer of the reactor in the gas recirculation line. As co monomer used hexene. With this stream was mixed triethylaluminium (TEAL) in a 1 wt.%-aqueous solution in isopentane solvent used as a carrier. To maintain a constant target of the composition of the regulated consumption of individual streams of ethylene, hydrogen and co monomer. To maintain a constant partial pressure of ethylene was adjusted to the concentration of ethylene. To maintain a constant molar ratio between hydrogen and ethylene regulate gas chromatograph, providing relative constancy of the composition of the recirculated gas stream.

The solid catalyst was injected directly into the fluidized bed using purified nitrogen as a carrier. To maintain constant flow regulating the flow of catalyst. The reaction layer of the growing polymer particles maintained in a fluidized state by a constant flow of raw materials and recirculation of gas passing through the reaction zone. To achieve this, the velocity of the gas was maintained at a level of 1-3 ft/s (up to 30.5-91.4 cm/s). The reactor was operated under a total pressure of 300 psig (2069 kPa). To maintain a constant temperature in the reactor the temperature of the recirculation gas is constantly regulated by raising or lowering in accordance with any changes in the speed of heat in the polymerization.

The height of the fluidized bed was maintained at a constant level by removing the part of this layer with a flow rate equal to the volumetric rate of production of the powdered product. The semi-continuous product was removed through a series of valves in the chamber of fixed volume, the gases from which are simultaneously returned to the reactor. This gave owassa gases back to the reactor. This product was purged to remove trapped hydrocarbons and treated weak current humidified nitrogen for decontamination of all traces of residual amounts of catalyst (table. 11).

The polymers obtained according to the present invention can be used in a wide variety of products and regions. The density of such polymers, as a rule, 0.900-0,970 g/CC, preferably 0,905-0,965 g/CC, more preferably from 0.910-0,915 g/CC to about 0,935-0,940 g/CC, and most preferably more 0,915 g/cubic cm Polymers obtained by the method according to the invention can be used in the operations of molding extrusion and coextrudable materials such as films, sheets and fibers, as well as blow molding, injection molding and rotary molding. The films are materials, molded blown, and irrigation in the form of single layer and multilayer structures produced by coextruding or lamination. Such films can be used in the form of shrink films, adherent films, stretch film, sealing films for welding, oriented films, packaging for Breakfast packages for large loads, bags of groceries, pack the wounds, etc. in those applications where they are in contact and not in contact with food products. The process of forming fibers include spinning from melt spinning from solution and blow molding fibers from the melt. Such fibers can be used in the form of woven and nonwoven materials for the manufacture of filters in the form of salfetochnyj of textiles, clothing, health care workers, geotextile materials, etc. To conventional extruded products include tubes for medical purposes, coatings for wires and cables, geomembranes and facing materials for swimming pools. Molded products include single and multi-layered constructions in the form of bottles, tanks, large hollow articles, rigid food containers, toys, etc.

Although the present invention is described and illustrated with reference to specific ways of its implementation, for any expert in the art it is obvious that the scope of the invention is much broader than presented in this description. For example, the present invention provides use of the device for removal of oligomers from the recirculation flow, such as described in U.S. patent 5126414 that on the nom reactor or series of reactors installed in series, or even in a series, in which one of the reactor is the reactor suspension polymerization, and the other reactor is a reactor for gas-phase process. In the case of series reactors, the possibility of using traditional catalyst of Ziegler-Natta in the same reactor in the implementation of the known method according to any of the patents and the implementation of the method according to the invention in the second reactor. For this reason, the true scope of the present invention is defined only by the attached claims.

1. Method for continuous gas-phase or slurry polymerization of one or more olefins in a reactor in the presence of a metallocene catalyst system, in which the polymerization of the contents of the cleaning agent is 0 to 10 million-1the total weight of the recirculation flow, however, the performance of the reactor is more than 500 lbs/HR (227 kg/HR) of polymer product, preferably from more than 500 lbs/HR (227 kg/HR) up to 200,000 lb/h (90900 kg/h) of polymer product.

2. The method according to p. 1, which is a method for continuous gas-phase polymerization of one or more olefins in a reactor in the presence of metallic">

3. The method according to p. 1, which is a method for continuous gas-phase polymerization of one or more olefins (individually or in combination) in the presence of a metallocene catalyst system on the media in the reactor, and the contents of the cleaning agent selected from the group comprising triethylamine, triisobutylaluminum, trimethylaluminum, etimani, diethylzinc and their mixtures, in the process of polymerization ranges from 0 to 10 million-1the total weight of the recirculation flow.

4. The method according to PP.1 to 3, which is a gas-phase process.

5. The method according to p. 1, in which as a cleaning agent using at least one ORGANOMETALLIC compound containing a metal of group 12 or 13.

6. The method according to p. 1, in which as a cleansing agent selects at least one compound corresponding to the General formula RnA, where A denotes an element of group 12 or 13, preferably each R, which may be identical or different, denotes a substituted or unsubstituted remotemachine or branched alkyl radical, cyclic hydrocarbonyl radical, alkylcyclohexanes radical, aromatic radical or alkoxy RA is the-olefins, containing 3 to 20 carbon atoms.

8. The method according to PP.1 and 3 to 7, in which the cleaning agent is administered together with a metallocene catalyst system and/or administered for the first 3 h after entry into the reactor metallocene catalyst system and/or impose until then, until it reaches the catalyst productivity of greater than 1000 grams of polymer per 1 g of metallocene catalyst system, and/or injected so that the content of small particles with sizes less than 125 microns (of 0.0125 cm) was less than 10%, preferably taking into account all the above conditions or combinations thereof.

9. The method according to PP.1 to 8, in which the performance of the reactor is more than 1000 pounds (455 kg) of polymer product per hour, preferably more than 10,000 pounds (4540 kg) of polymer product per hour, most preferably more than 50,000 pounds (22700 kg) of polymer product per hour.

10. The method according to PP.1 and 3 to 9, which represents the polymerization process of one or more olefins in the presence of at least one metallocene catalyst component and the activator in a reactor with a fluidized bed, and this method provides for the input of a cleaning agent into the reactor so arr is the NRN product less than 50 part/million

11. The method according to PP.1 to 10, in which the process is carried out so that the weight proportion of olefinic hydrocarbon oligomers with number of carbon atoms less than or equal to 30 in the resulting polymer product was less than 0.06.

12. The method according to PP. 1 and 3 to 11, in which the cleaning agent is injected so that the total weight of the contents of C14- C18oligomers in the resulting polymer product was less than 40 million-1preferably less than 20 million-1more preferably less than 10 million-1.

13. Method for continuous gas-phase or slurry polymerization of alpha-olefin monomers containing 2 to 20 carbon atoms, or copolymerization of one or more alpha-olefin monomers with another alpha-olefin, cycloolefin, styrene, polar vinyl monomers, diolefins, polyene, norbornene, norbornadiene, acetylene or aldehyde monomers in the reactor with a fluidized bed, which comprises the following stages: a) enter the recirculation flow in the reactor, where the recycle stream comprises the monomer(s); b) enter metallocene catalyst system into the reactor; enter a cleansing agent in a quantity less than 300 million-1, suppose the agent and/or enter the number of the total weight of the fluidized bed, which provides for obtaining a polymer product in which the total weight content of olefinic C14- C18oligomers is less than 50 million-1d) removal of the recirculation stream from the reactor; d) cooling the recycle stream; (e) enter into the recirculating stream of additional monomer(s) to replace the polymerized monomer(s); g) re-enter the recirculation flow in the reactor, and C) removing from the reactor the polymer product with a speed of more than 500 lb/HR (227 kg/HR), preferably from more than 500 lbs/HR (227 kg/HR) up to 200,000 lb/h (90900 kg/h).

14. The method according to p. 13, which represents a process of polymerization of olefin(s), and the method comprises the stage of entering the entire quantity of the purifying agent continuously or intermittently into the reactor, preferably at the initial stage of the process, and the stage of removing at least 95% or more of the cleansing agent.

15. The method according to p. 13 or 14, which is a gas-phase process.

16. The method according to PP.13 - 15, which as a cleaning agent using at least one ORGANOMETALLIC compound containing a metal of group 12 or 13.

17. The method according to PP.13 - 16, which as who appoints the element group 12 or 13, preferably each R, which may be identical or different, denotes a substituted or unsubstituted remotemachine or branched alkyl radical, cyclic hydrocarbonyl radical, alkylcyclohexanes radical, aromatic radical or alkoxy radical and n denotes 2 or 3.

18. The method according to PP.13 - 17, in which the content of the purifying agent in the reactor is less than 30 million-1preferably less than 20 million-1even more preferably less than 10 million-1and most preferably less than 5 million-1.

19. The method according to PP.13 - 18, in which the monomer(s) is(are) an ethylene and alpha-olefins containing 3 to 20 carbon atoms.

20. The method according to PP.13 - 19, in which the cleaning agent is administered together with a metallocene catalyst system and/or administered for the first 3 h after entry into the reactor metallocene catalyst system and/or impose until then, until it reaches the catalyst productivity of greater than 1000 grams of polymer per 1 g of metallocene catalyst system, and/or injected so that the content of small particles with sizes less than 125 microns (of 0.0125 cm) was less than 10%, preferably pregnancy reactor is more than 1000 pounds (455 kg) of polymer product per hour, preferably more than 10,000 pounds (4540 kg) of polymer product per hour, most preferably more than 50,000 pounds (22700 kg) of polymer product per hour.

22. The method according to PP.13 - 21, which represents a polymerization process of one or more olefins in the presence of at least one metallocene catalyst component and the activator in a reactor with a fluidized bed, and this method provides for the input of a cleaning agent into the reactor so that the total weight content of olefinic C14- C18oligomers in the resulting polymer product was less than 50 million-1.

23. The method according to PP. 13 - 22, which is carried out so that the weight proportion of olefinic hydrocarbon oligomers with number of carbon atoms less than or equal to 30 in the resulting polymer product was less than 0.06.

24. The method according to PP.13 - 23, in which the cleaning agent is injected so that the total weight of the contents of C14- C18oligomers in the resulting polymer product was less than 40 million-1preferably less than 20 million-1more preferably less than 10 million-1.

 

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