KR20130019793A - Method of preparing polyolefin - Google Patents

Abstract

PURPOSE: A manufacturing method of a polyolefin resin is provided to obtain a polyolefin which is excellent in a full notch creep test and is suitable for molding a medium blow-molding by excellent processability. CONSTITUTION: A manufacturing method of a polyethylene resin comprises: a step of preparing a low molecular weight ethylene polymer by reacting an ethylene monomer and a catalyst under the presence of a supported metallocene catalyst in a first reactor; a step of discharging gas by transferring a slurry mixture which contains the low molecular weight ethylene polymer to a flash vessel; and a step of reacting the slurry mixture and ethylene monomer under the presence of a chain propagation agent in a second reactor to manufacture a high molecular weight ethylene polymer. [Reference numerals] (AA) First reactor; (BB) Flash vessel; (CC) Second reactor; (DD) Post reactor

Description

Method for preparing polyolefin resin {Method of preparing polyolefin}

The present invention relates to a method for producing a polyolefin resin, and more particularly, a polydispersity index (PDI) of a polyolefin prepared by using a metallocene supported catalyst and two or more stages of a multistage polymerization process, and has a high density ratio. The present invention relates to a method for producing a polyolefin resin having excellent stress notch creep test (FNCT) and excellent processing, which is particularly suitable for blow molding molding.

In general, products manufactured using blow molding require excellent processability and stress cracking resistance. In addition to satisfying these properties, efforts have been made to reduce the amount of material used for cost reduction, which must be supported by excellent physical properties and stress cracking resistance.

In general, metallocene catalysts using Group 4 transition metals are easier to control the molecular weight and molecular weight distribution than conventional Ziegler-Natta catalysts, and can control the comonomer distribution of polymers to make products with improved mechanical properties and processability. Has been used. Nevertheless, polymers prepared using metallocene catalysts have a problem of poor workability due to narrow molecular weight distribution, and therefore, satisfying processability, density and stress cracking resistance at the same time has been an important development goal.

In the case of blow-molded products, polyethylene made of metallocene has high viscosity at high shear rate, so that a lot of load or pressure is extruded at the time of extrusion, thereby reducing extrusion productivity and uneven surface of the molded article. The parison's stability may also be degraded. In particular, in the case of a small blow molded product in which the size of the blow molded product container is lowered to 0.5 l to 20 l or less, physical property requirements such as flexural strength are increased, thereby making it more difficult to match the processability with improved physical properties.

In addition, in order to improve physical properties in the multistage polymerization process, polyolefins having a high melt index are produced in the first reactor. When a metallocene supported catalyst is used, the polymerization may not be sufficiently performed in the second reactor depending on the polymerization duration in the reactor. In this case, the average molecular weight of the material finally produced may not be improved and thus the melt index of the desired final polyolefin may not be matched.

Therefore, when the metallocene catalyst is applied to a multi-stage reactor, it is urgent to develop a method for producing a polyolefin, in which excellent mechanical properties used by maintaining the activity of the catalyst sufficiently and maintaining processability are greatly improved.

In order to solve the problems of the prior art as described above, the present invention provides a longer lasting activity of the metallocene supported catalyst introduced in the first reactor when the polyolefin is prepared using a metallocene supported catalyst and two or more multistage polymerization processes. PDI, which is a polydispersity of polyolefins, is high by increasing the amount of polyolefins produced in the second or more reactors, and has a good stress notch (Full Notch Creep Test (FNCT) to density), and is easy to process and blow molding. It is an object to provide a method for producing a polyolefin which is particularly suitable for molding.

These and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention, when preparing a polyolefin using a metallocene supported catalyst and two or more stages of the multi-stage polymerization process, in the first reactor with the ethylene monomer in the presence of a metallocene supported catalyst and an inert gas After the catalyst was reacted and the gas was discharged from the flash vessel, the slurry mixture and the ethylene monomer passed from the first reactor were reacted in the second reactor in the presence of a molecular propagation agent (CPA) to prepare an ethylene polymer having a wide molecular weight distribution. Characterized in that it comprises a step.

As described above, the polydispersity of the polyolefin prepared by increasing the weight ratio of the polyolefin produced in the second or more reactors by making the activity of the supported metallocene catalyst introduced in the first reactor longer by the present invention High phosphorus PDI, excellent stress cracking resistance to density, and easy processing, it is possible to produce a polyolefin particularly suitable for medium blow molding molding.

1 is a schematic diagram illustrating a multi-stage polymerization process of polyethylene using a continuous CSTR reactor according to one embodiment of the present invention.
Figure 2 is a graph showing the input amount and cumulative input amount of ethylene according to Example 4 and Comparative Example 3 of the present invention.

The present invention provides a method for producing polyethylene by a multistage polymerization process using a metallocene supported catalyst, wherein the polyethylene is polymerized in the presence of a metallocene supported catalyst and an inert gas (nitrogen) in a first reactor, and the gas is flashed in a flash vessel. After discharging, the second reactor is characterized by finally preparing a polyolefin having a wide molecular weight distribution by adding a molecular weight regulator.

The present invention will be described in detail as follows.

Method for producing a polyethylene resin according to the present invention is a method for producing polyethylene by reacting an ethylene monomer and a catalyst in a reactor in which the first reactor and the second reactor is connected in series, (i) a metallocene supported catalyst in the first reactor and Reacting the catalyst with the ethylene monomer in the presence of an inert gas to produce an ethylene polymer; (ii) transferring the slurry mixture to a flash vessel to evacuate the gas; And (iii) reacting the slurry mixture and the ethylene monomer passed from the first reactor in the presence of the molecular weight regulator in the second reactor to produce an ethylene polymer having a broad molecular weight distribution.

The present invention produces polyethylene by reacting an ethylene monomer and a catalyst in a reactor in which a first reactor, a flash vessel and a second reactor are connected in series, and a post reactor may be further connected to the second reactor.

Polymerization Process of the First Reactor

The first reactor produces an ethylene polymer by reacting the catalyst with an ethylene monomer in the presence of a metallocene supported catalyst and an inert gas. It is preferable that the said inert gas is nitrogen.

The nitrogen increases the duration of activity in the second reactor of catalyst. That is, to suppress the rapid reaction of the initial polymerization of the metallocene supported catalyst in the first reactor, and then to help the action of the catalyst in the second reactor to increase the amount of polyethylene produced in the second reactor / the amount of polyethylene produced in the first reactor Play a role.

Hydrogen may not be used in the preparation of the ethylene polymer or may be further added in an amount of 0 to 5% by weight of the total monomers. If it is outside the above range may be increased in the volatile components during processing of the final product.

The metallocene supported catalyst is preferably a hybrid metallocene supported catalyst comprising a carrier, a first promoter, a second promoter, a first metallocene compound, and a second metallocene compound.

As a carrier used for the metallocene supported catalyst, for example, silica, silica-alumina, silica-magnesia and the like dried at high temperature may be used. The carrier is dried at a high temperature, and the drying temperature of the carrier is 180 to 800 ° C. When the carrier is lower than 180 ° C, there is too much moisture, which may degrade the performance due to the cocatalyst. It is not preferable because there are not many groups and only siloxane groups are left to decrease the reaction site with the promoter.

The first promoter may be represented by the following Chemical Formula 1 as an organometallic compound containing aluminum.

In Formula 1, R ¹ is the same or different halogen radicals, C1-C20 hydrocarbyl radicals or C1-C20 hydrocarbyl radicals substituted with halogen, n is an integer of 2 or more.

The compound of Formula 1 may be present in a linear, circular or reticular form, for example methyl aluminoxane (MAO), ethyl aluminoxane, isobutyl aluminoxane or butyl aluminoxane.

The second cocatalyst may be a borate-based compound containing boron represented by the following formula (2).

In Formula 2, T ⁺ is a + monovalent polyatomic ion, B is boron in a +3 type oxidation state, and Q is independently hydride, dialkylamido, halide, alkoxide, aryloxide, hydrocarbyl, halo It is selected from carbyl and halo-substituted hydrocarbyl radicals, wherein Q has up to 20 carbons, but at less than one position Q is a halide.

Non-limiting examples of the compound of Formula 2 include trisubstituted ammonium salts such as trimetalammonium tetraphenylborate, methyldioctadecylammonium tetraphenylborate, triethylammonium tetraphenylborate, tripropylammonium tetraphenylborate , Tri (n-butyl) ammonium tetraphenylborate, methyltetracyclocyclodecylammonium tetraphenylborate, N, N-dimethylaninium tetraphenylborate, N, N-diethylaninium tetraphenylborate, N, N -Dimethyl (2,4,6-trimethylaninynium) tetraphenylborate, trimethylammonium tetrakis (pentafluorophenyl) borate, methylditetradecylammonium tetrakis (pentaphenyl) borate, methyldioctadecylammonium tetrakis ( Pentafluorophenyl) borate, triethylammonium, tetrakis (pentafluorophenyl) borate, tripropylammonium tetrakis (pentafluoro) Rophenyl) borate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, tri (secondary-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylaninynium tetrakis ( Pentafluorophenyl) borate, N, N-diethylaninium tetrakis (pentafluorophenyl) borate, N, N-dimethyl (2,4,6-trimethylaninynium) tetrakis (pentafluorophenyl) borate , Trimethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, triethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, tripropylammonium tetrakis (2, 3,4,6-tetrafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (2,3,4,6-, tetrafluorophenyl) borate, dimethyl (t-butyl) ammonium tetrakis (2 , 3,4,6-tetrafluorophenyl) borate, N, N-dimethylaninium tetrakis (2,3,4,6-tetrafluorophenyl) borate, N, N-diethyla Tetrakis (2,3,4,6-tetrafluorophenyl) borate and N, N-dimethyl- (2,4,6-trimethylaninynium) tetrakis- (2,3,4,6-tetrafluoro Rophenyl) borate, dialkyl ammonium salts such as dioctadecylammonium tetrakis (pentafluorophenyl) borate, ditetradecylammonium tetrakis (pentafluorophenyl) borate and dicyclohexylammonium tetrakis (pentafluoro Phenyl) borate; Trisubstituted phosphonium salts such as triphenylphosphonium tetrakis (pentafluorophenyl) borate, methyldioctadecylphosphonium tetrakis (pentafluorophenyl) borate and tri (2,6-, dimethylphenyl) Phosphonium tetrakis (pentafluorophenyl) borate. Long-chain alkyl mono- and disubstituted ammonium complexes, especially C14-C20 alkyl ammonium complexes, especially methyldi (octadecyl) ammonium tetrakis (pentafluorophenyl) borate and methyldi (tetradecyl) ammonium tetrakis (pentafluorophenyl Borate or mixtures comprising them are preferred.

The first metallocene compound may be a compound represented by Formula 3 below, and the second metallocene compound may be a compound represented by Formula 4 below.

In Chemical Formula 3 or 4

R ^m , R ⁿ are the same or different hydrogen radicals, alkyl having 1 to 20 carbon atoms, cycloalkyl, aryl, alkenyl, alkylaryl, arylalkyl, arylalkenyl radicals or alkylsilyl radicals, and R ¹ and R ² are The same or different hydrogen or hydrocarbyl radicals of 1 to 6 carbon atoms, a, a ', b or b' are each an integer of 1 to 4,

M is a transition metal of group 4B, 5B or 6B of the periodic table,

Q is a halogen radical or an alkyl radical of 1 to 20 carbon atoms alkenyl radical, an aryl radical alkylaryl radical, an arylalkyl radical or an alkylidene radical of 1 to 20 carbon atoms,

B is any one selected from the group consisting of alkyl radicals having 1 to 4 carbon atoms or hydrocarbyl radicals containing silicon, germanium, phosphorus, nitrogen, boron or aluminum,

J is any one selected from the group consisting of NR ⁵ , O, PR ⁵ and S, wherein R ⁴ is an alkyl radical or substituted alkyl radical of 1 to 20,

Preferably any one hydrogen radical present in R ^m , R ⁿ , B or R ⁵ is alkoxy, aryloxy, alkylthio, arylthio, amino, phenyl or substituted phenyl having 1 to 20 carbon atoms, preferably Alkoxy having 1 to 20 carbon atoms,

Representative examples of such functional groups are from the group consisting of methoxymethyl, t-butoxymethyl, tetrahydropyranyl, tetrahydrofuranyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl and t-butyl It may be any one selected.

Meanwhile, a representative example of the metallocene compound represented by Chemical Formula 3 of the present invention is [AO- (CH ₂ ) _a -C ₅ H ₄ ] ₂ ZrCl ₂ , wherein a is an integer of 4 to 8, and A May be any one selected from the group consisting of methoxymethyl, t-butoxymethyl, tetrahydropyranyl, tetrahydrofuranyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl and t-butyl have.

Representative examples of the metallocene compound represented by Chemical Formula 4 of the present invention are [(A'-D- (CH ₂ ) _a )] (CH ₃ ) X (C ₅ Me ₄ ) (NCMe ₃ )] TiCl ₂ . , X is methylene, ethylene or silicon, D is oxygen or nitrogen atom, A 'is hydrogen, alkyl having 1 to 20 carbon atoms, alkenyl, aryl, alkylaryl, arylalkyl, alkylsilyl, arylsilyl, methoxymethyl , t-butoxymethyl, tetrahydropyranyl, tetrahydrofuranyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl and t-alkylsilyl, arylsilyl, methoxymethyl, t-butoxymethyl , Tetrahydropyranyl, tetrahydrofuranyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl, and t-butyl.

The most preferable manufacturing sequence for preparing the mixed metallocene supported catalyst is the step of preparing a carrier on which the first metallocene compound is supported by reacting the first metallocene compound on the carrier, wherein the first metallocene compound is Preparing a carrier on which the first metallocene compound and the first promoter are supported by reacting the first promoter on the supported carrier; a second on the carrier on which the first metallocene compound and the first promoter are supported; Reacting the metallocene compound; And reacting the second cocatalyst to the metallocene catalyst on which the first metallocene compound, the first cocatalyst, and the second metallocene compound are supported, to finally form the first metallocene compound, the second metallocene compound, It is preferable that the first cocatalyst, the second cocatalyst carried on the metallocene catalyst is supported.

This process is carried out step by step and it is preferable to go through the process of washing with a solvent between each step.

The organoaluminum compound may be continuously introduced into the first reactor and the second reactor as a substance for removing water in the reactor. The organoaluminum compound is preferably selected from the group consisting of trialkylaluminum, dialkyl aluminum halides, alkyl aluminum dihalides, aluminum dialkyl hydrides and alkyl aluminum sesqui halides. More preferably Al (C ₂ H ₅ ) ₃ , Al (C ₂ H ₅ ) ₂ H, Al (C ₃ H ₇ ) ₃ , Al (C ₃ H ₇ ) ₂ H, Al (iC ₄ H ₉ ) ₂ H, Al (C ₈ H ₁₇ ) ₃ , Al (C ₁₂ H ₂₅ ) ₃ , Al (C ₂ H ₅ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) ₂ H, Al (iC ₄ H ₉ ) ₃ , (C ₂ H ₅ ) ₂ AlCl, (iC ₃ H ₉ ) ₂ AlCl or (C ₂ H ₅ ) ₃ Al ₂ Cl ₃ do. The addition amount of the organoaluminum compound can be selected without particular limitation as long as it can remove water, but preferably 0.1 mole to 10 mole per kg of hexane.

The residence time of the raw material in the polymerization process of the first reactor can be selected without particular limitation as long as it can form an ethylene polymer having an appropriate molecular weight distribution and density distribution, but a range of 1 hour to 3 hours is preferable. If the time is less than the above range may cause a problem of poor processability of the final polyethylene product, if it is larger than the above range is not efficient in terms of productivity due to a long process cycle relative to the yield.

The inert gas such as nitrogen added and ethylene mass ratio may be selected depending on the specific properties of the catalyst as well as the molecular weight of the desired end product, but is preferably from 1:10 to 1: 100. If a smaller amount of inert gas is added than the above range, the catalyst activity is not sufficiently realized in the second reactor, so that a desired molecular weight distribution cannot be obtained. If a larger amount of inert gas is added, the catalyst is added in the first reactor. May not be sufficiently implemented.

The polymerization reaction temperature in the first reactor can be selected without particular limitation as long as it can form an appropriate molecular weight distribution and density distribution, but is preferably 70 to 90 ° C. If the temperature is lower than the above range, the polymerization reaction rate is reduced to increase the product manufacturing cost. If the temperature is higher than the above range, fouling in the reactor may be caused.

The polymerization reaction pressure in the first reactor can be selected without particular limitation as long as it can form an appropriate molecular weight distribution and density distribution, but is preferably 8 to 10 bar to maintain a stable continuous process state.

The reaction mixture may further comprise a diluent component, most of the diluent being hexane, and may contain small amounts of other alkanes or alkenes such as butane, pentane. Such diluents may be introduced in gaseous or liquid form, or both, which may be added into the bottom of the reactor or directly into the polymer bed. The amount of the diluent added is preferably a mass ratio of the diluent and ethylene of 1.1 to 5.1, and if lower than 1.1, there is a problem in heat removal, and if higher than 5.1, the production efficiency is inferior to the reactor size.

The ethylene polymer formed in the first reactor has a weight average molecular weight of 10,000 to 100,000, a polydispersity of 1.5 to 5.0, and a low molecular weight of 1000 to 10 at 5 kg, 190 ° C conditions. In addition, the production rate of the polymer produced in the first reactor of the final product is preferably 40 to 70% by weight. The polymerization reaction in the first reactor can be either gas phase polymerization or liquid phase polymerization, and liquid phase polymerization having a slurry phase is preferable for the efficiency of the reaction.

Flash vessel ( flash vessel )

Located between the first reactor and the second reactor to release the gas mixture to the outside while stirring the slurry mixture conveyed from the first reactor to reduce the ratio of hydrogen and nitrogen.

During the polymerization process for the preparation of the solid polymer, a polymer effluent comprising a slurry of polymer solids is typically formed in a liquid medium comprising a reaction diluent and an unreacted monomer, the effluent being withdrawn to recover the polymer solid from the polymerization reactor effluent. It is necessary to separate the polymer solids from the residue. To recover diluents, monomers or comonomers from the reaction effluent, a flash process is generally used when the diluent is removed from the effluent. In the polymerization process of the present invention, this principle of the instantaneous evaporation process is applied to selectively remove the most volatile hydrogen and nitrogen by using a flash vessel between the first reactor and the second reactor.

The pressure is controlled by controlling the pressure of the first reactor to 9 bar or less and the pressure of the second reactor to 7 bar or more. The temperature is the same as the operating range of the first reactor. That is, it is preferable that it is 70-90 degreeC. In addition, the residence time is a time required for gas discharge, preferably 5 minutes to 30 minutes.

Polymerization Process of Second Reactor

In the second reactor connected in series with the first reactor, a high molecular weight ethylene polymer is prepared by further adding and reacting the ethylene monomer and the comonomer in the presence of a molecular weight regulator without the addition of additional catalyst.

The molecular weight modifier is preferably an organometallic complex, more preferably an organometallic complex, most preferably a cyclopentadienyl metal compound represented by Formula 5 and an organoaluminum represented by Formula 6 It is an organometallic complex prepared by reacting a compound. In this case, the polymer melt index is lowered, the molecular weight polydispersity is increased, and the stress cracking resistance is higher than the density or polymer melt index.

In Formula 5, Cp ¹ and Cp ² are independently a pentacyclopentadienyl, indenyl group, fluorenyl group, or a derivative thereof, M is titanium, zirconium or hafnium, and X is a halogen element.

Specific examples of the cyclopentadienyl metal compound include biscyclopentadienyl titanium dichloride, biscyclopentadienyl zirconium dichloride, biscyclopentadienyl hafnium dichloride, bisindenitanium dichloride, and bisfluorenyl titanium dichloride. At least one selected from the group consisting of chlorides and the like is preferable.

In Formula 6, R ¹ , R ^2, or R ³ may be independently C 1 to C 20 alkyl substituents or halogen, and may include a hetero element such as nitrogen or oxygen.

The organoaluminum compound is trimethyl aluminum, triethyl aluminum, tripropyl aluminum, triisopropyl aluminum, triisobutyl aluminum, trihexyl aluminum, trioctyl aluminum, dimethylaluminum chloride, diethyl aluminum chloride, dipropylaluminum chloride, diiso It is preferably one or more selected from the group consisting of butylaluminum chloride, dihexylaluminum chloride, dimethylaluminum dichloride, ethylaluminum dichloride, propylaluminum dichloride, isobutylaluminum difluoride and ethylaluminum sesquifluoride.

The molar ratio (M: Al) of the cyclopentadienyl metal compound (M) and the organoaluminum compound (Al) is preferably 1.0: 1 to 1: 100.

The molecular weight regulator to be added preferably has a M content of the organometallic complex of 0.001 μmol · 1 kg to 10 μmol · 1 kg based on 1 kg of total ethylene injected into the total reactor. If the molecular weight modifier is added less than this range, the molecular weight and polydispersity of the final product cannot be sufficiently increased, and if it is added more than this range, the activity of the catalyst is too low to increase the polydispersity sufficiently.

The comonomer is not used in the preparation of the polyethylene, or is preferably added to the second reactor during the preparation of the high molecular weight ethylene polymer. As the comonomer usable in the second reactor, C2-C10 alpha-olefin may be used, and 1-butene or 1-hexene is preferably used. The comonomer can be further added in an amount of 0 to 20% by weight of the total monomers.

When comonomers are used a lot, tie-molecules are formed on the high molecular weight side to improve impact strength and environmental stress crack resistance test (ESCR), while lowering the density of polymers to increase flexural strength. Weakens.

The residence time of the raw material in the polymerization process of the second reactor can be selected without particular limitation as long as it can form an ethylene polymer having an appropriate molecular weight distribution and density distribution, but is preferably in the range of 1 to 3 hours. If the time is less than the above range may cause a problem of environmental stress cracking resistance of the final polyethylene product is less than the above range, the production efficiency in the second reactor is not higher because the production efficiency in the second reactor is lower than the range.

The polymerization reaction temperature in the second reactor can be selected without particular limitation as long as it can form an appropriate molecular weight distribution and density distribution, but is preferably 60 to 90 ° C. If the temperature is lower than the above range, the polymerization reaction rate is reduced to increase the product manufacturing cost. If the temperature is higher than the above range, fouling in the reactor may be caused.

The polymerization reaction pressure in the second reactor can be selected without particular limitation as long as it can form an appropriate molecular weight distribution and density distribution, but is preferably 6 to 9 bar to maintain a stable continuous process state.

The reaction mixture may further comprise a diluent component, most of the diluent being hexane, and may contain small amounts of other alkanes or alkenes such as butane, pentane. Such diluents may be introduced in gaseous or liquid form, or both, which may be added into the bottom of the reactor or directly into the polymer bed. When the amount of diluent is added, the mass ratio of the diluent and ethylene is preferably 1: 1 to 5: 1, and when the ratio is lower than 1: 1, there is a problem in heat removal, and when the ratio is higher than 5: 1, the production efficiency is lower than the reactor size.

The ethylene polymer formed in the second reactor has a weight average molecular weight of 150,000 to 300,000, a polydispersity of 5 to 20, a melt index of 5kg, a high molecular weight of 10 to 0.1 at 190 ℃ conditions. In addition, the production rate of the polymer produced in the second reactor of the final product is preferably 30 to 60% by weight. The polymerization reaction in the second reactor can be either gas phase polymerization or liquid phase polymerization, and liquid phase polymerization having a slurry phase is preferable for the efficiency of the reaction.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

Manufacturing example  1: [t- This -O ( CH ₂ ) ₆ - C ₅ H ₄ ] ₂ ZrCl ₂ Synthesis of

Using 6-chlorohexanol, Tetrahedron Lett . 2951 (1988)) to prepare t-butyl-O- (CH ₂ ) ₆ -Cl, which was reacted with NaC ₅ H ₅ to t-butyl-O- (CH ₂ ) ₆ -C ₅ H ₅ was obtained (yield 60%, bp 80 ° C / 0.1 mmHg).

2.0 g (9.0 mmol) of t-butyl-O- (CH ₂ ) ₆ -C ₅ H ₅ was dissolved in THF at -78 ° C, and 1.0 equivalent of normal butyllithium (n-BuLi) was slowly added thereto, followed by room temperature. After raising the temperature, the reaction was carried out for 8 hours. The reaction solution was slowly added to a suspension solution of ZrCl ₄ (THF) ₂ (1.70 g, 4.50 mmol) / THF (30 ml) at −78 ° C., followed by further reaction at room temperature for 6 hours to form the final reaction. A solution was obtained.

The reaction product was dried in vacuo to remove all volatiles, and then hexane was added to the remaining oily liquid and then filtered using a schlenk glass filter. The filtered solution was dried in vacuo to remove hexane, and then hexane was added thereto to induce precipitation at low temperature (-20 ° C). The precipitate obtained was filtered at low temperature to give a white solid [t-Bu-O (CH ₂ ) ₆ -C ₅ H ₄ ] ₂ ZrCl ₂ compound in a yield of 92%. The measured ¹ H NMR and ¹³ C NMR data of [t-Bu-O (CH ₂ ) ₆ -C ₅ H ₄ ] ₂ ZrCl ₂ were as follows.

¹ H NMR (300 MHz, CDCl ₃ ): 6.28 (t, J = 2.6 Hz, 2H), 6.19 (t, J = 2.6 Hz, 2H), 3.31 (tJ = 6.6 Hz, 2H), 2.62 (t, J = 8 Hz, 2H), 1.7-1.3 (m, 8H), 1.17 (s, 9H)

13 C NMR (CDCl ₃ ): 135.09, 116.66, 112.28, 72.42, 61.52, 30.66, 30.61, 30.14, 29.18, 27.58, 26.00

Manufacturing example  2: [ methyl (6-t- buthoxyhexyl ) silyl (η ⁵ -tetramethylcyclopentadienyl) (t- butylamido ) TiCl ₂ Synthesis of

50g of Mg (solid) was added to a 10L reactor at room temperature, and then 300ml of THF was added thereto. After 0.5 g of I ₂ was added thereto, the reactor temperature was maintained at 50 ° C.

After the reactor temperature was stabilized, 250 g of 6-t-butoxyhexyl chloride was added to the reactor at a rate of 5 ml / min using a feeding pump, and stirred for 12 hours. (6-t-butoxyhexyl chloride as the reactor temperature is increased about 4-5 ℃), 6-t-butoxy hexyl magnesium chloride (6-t-buthoxyhexyl magnesium chloride) was prepared.

The 6-t- portion was ethoxy hexyl magnesium chloride, obtained in the reaction solution of the black, was added after the water taken from the reaction solution 2ml of the black obtain an organic layer, a ¹ H-NMR that the compound contained in the organic layer The result of the Grannard reaction was confirmed to be 6-t-butoxyhexane (6-t-buthoxyhexane).

500 g of MeSiCl ₃ and 1 L of THF were added to a separate reactor, and the reactor temperature was cooled to -20 ° C. Into this reactor, 560 g of 6-t-butoxyhexyl magnesium chloride prepared in the future was introduced at a rate of 5 mL / min using an infusion pump, and then stirred for 12 hours while slowly raising the temperature of the reactor to room temperature.

After 12 hours of stirring, it was confirmed that white MgCl ₂ salt was produced. 4 L of hexane was added thereto, and then the salt was removed through an experimental pressure dehydration filtration device (labdori, Han River Engineering Co., Ltd.) to obtain a filtered solution.

The filtered solution was added to the reactor and hexane was removed at 70 ° C. to obtain a pale yellow liquid, which was confirmed to be a methyl (6-t-butoxyhexyl) dichlorosilane compound through ¹ H NMR.

¹ H NMR (CDCl ₃ ): 3.3 (t, 2H), 1.5 (m, 3H), 1.3 (m, 5H), 1.2 (s, 9H), 1.1 (m, 2H), 0.7 (s, 3H)

1.2 mol (150 g) of tetramethylcyclopentadiene and 2.4 L of THF were added to a separate reactor, and the reactor temperature was cooled to -20 ° C. Then, 480 mL of n-BuLi at a concentration of 2.5 M was charged using an infusion pump. Was introduced at a rate. After the addition of n-BuLi, the reactor was slowly stirred at room temperature for 12 hours, and then, 326 g (350 ml) of methyl (6-t-butoxyhexyl) dichlorosilane was rapidly added. Was added to the reactor. After stirring for 12 hours while slowly raising the reactor temperature to room temperature, the reactor temperature was cooled to 0 ° C and 2 equivalents of t-BuNH ₂ was added thereto.

After stirring the reactor temperature slowly to room temperature for 12 hours, THF was removed, 4 L of hexane was added, and salt was removed through an experimental pressure dehydration filtration apparatus (labdori, Han River Engineering Co., Ltd.) to obtain a filtered solution. there was. After the filtered solution was added to the reactor again, hexane was removed at 70 ° C. to obtain a yellow solution, which was obtained via 1H NMR, methyl (6-t-butoxyhexyl) tetramethylcyclopentadienyl) t-butylamino. Silane (6-t-buthoxyhexyl) (tetramethylcyclopentadienyl) t-butylaminosilane was confirmed.

Reaction of methyl (6-t-butoxyhexyl) tetramethylcyclopentadienyl) t-butylaminosilane (6-t-buthoxyhexyl) (tetramethylcyclopentadienyl) t-butylamino silane with n-BuLi at -78 ° C and THF 10 mmol of TiCl ₃ (THF) ₃ was rapidly added to the resulting dilithium salt solution, and then stirred for 12 hours while slowly warming to room temperature at -78 ° C. After stirring for 12 hours, an equivalent amount of 10 mmol of PbCl ₂ was added to the reaction solution at room temperature, followed by stirring for 12 hours to obtain a dark black solution.

After removing THF from the dark black solution, hexane was added, followed by filtration to obtain a filtered solution. Hexane was removed from the filter solution and the remaining material was methyl (6-t-butoxyhexyl) silyl (η ⁵ -tetramethylcyclopentadienyl) (t-butylamido) TiCl ₂ via ¹ H NMR. It was confirmed that (methyl (6-t-buthoxyhexyl) silyl (η ⁵ -tetramethylCp) (t-butylamido) TiCl ₂ .

1 H NMR (CDCl ₃ ): 3.3 (s, 4H), 2.2 (s, 6H), 2.1 (s, 6H), 1.8-0.8 (m), 1.4 (s, 9H), 1.2 (s, 9H ), 0.7 (s, 3H)

Manufacturing example  3: Metallocene  Preparation of Supported Catalyst

30 ml of toluene was added to 3 g of calcined silica (Sylopol 2212, Grace Davison) having a pore volume of 1.47 ml / g at a surface area of 280 m ² / g, and then [t-Bu-O prepared in Preparation Example 1 at 70 ° C. 0.36 mmole of-(CH ₂ ) ₆ -C ₅ H ₄ ] ₂ ZrCl ₂ was added and reacted for 1 hour, and then the remaining solid was washed with toluene. The solid component was reacted with 15 ml (10 wt% toluene solution) of methylaluminoxane (MAO) at 70 ° C. for 2 hours, washed with toluene to remove the unreacted MAO solution, and a solid component containing methylaluminoxane was prepared.

Methyl (6-t-butoxyhexyl) silyl (η ⁵ -tetramethylcyclopentadienyl) (t-butylamido) TiCl ₂ prepared in Preparation Example ₂ Wash (methyl (6-t-buthoxyhexyl) silyl (η ⁵ -tetramethylcyclopentadienyl) (t-butylamido) TiCl ₂ 0.36 mmol, and the washed solid component and trityl tetrakis (penta-fluoro-phenyl) borate 1.2mmole of tetrakis (penta-fluoro-phenyl) borate, TB) was dried under reduced pressure at 50 ° C. using toluene as a solvent to prepare a supported metallocene catalyst in a solid state, at which time boron (B) / transition metal (Zr). ), The molar ratio was 1.3.

Manufacturing example  4: Preparation of Molecular Weight Regulator

1.25 g of bis (cyclopentadienyl) titanium dichloride (bis) and 10 ml of toluene were sequentially added to a 250 ml round bottom flask, followed by stirring. 10 ml of triisooctylalunium (1M in hexane) was added thereto, stirred at room temperature for 3 days, and then the solvent was removed in vacuo to obtain a green mixture, which was oxidized or colored as a reduced titanium. Did not change. In the following the green mixture was used as it is without purification. In addition, it was confirmed that the mixture of bis (cyclopentadienyl) octyl titanium (dioctylaluminium chloride) and bis (cyclopentadienyl) octyl titanium through 1H NMR.

¹ H NMR (CDCl ₃ , 500 MHz): 7.31 (br s, 10H), 2.43 (d, 4H), 1.95-1.2 (m, 28H), 1.2-0.9 (m, 19H)

Example  One

A multistage continuous CSTR reactor (see FIG. 1) consisting of two 0.2 m ³ capacity reactors, flash vessels and post reactors was used.

Hexane was 28 kg / hr, ethylene was 8 kg / hr, hydrogen was 4.0 g / hr, nitrogen was 0.1 kg / hr, and triethylaluminum (TEAL) was introduced at a flow rate of 30 mmol / hr, respectively. The metallocene supported catalyst prepared at was injected at 1 g / hr (180 μmol / hr). At this time, the first reactor was maintained at 84 ° C., the pressure was maintained at 9 bar, the residence time of the reactants was maintained at 2.5 hours, and the slurry mixture containing the polymer was continuously flashed while maintaining a constant liquid level in the reactor. vessel).

As the slurry mixture was fed into a flash vessel, the gas containing hydrogen, nitrogen, and ethylene was discharged to the outside, and the slurry mixture including the polymer collected in the lower layer was continuously passed to the second reactor.

Into the second reactor, 23 kg / hr of hexane, 6 kg / hr of ethylene, 90 cc / hr of 1-butene and triethylaluminum (TEAL) were injected at a flow rate of 25 mmol / hr, and the molecular weight regulator prepared in Preparation Example 4 was 80 µmol. injected at / hr. The second reactor was maintained at 80 ° C., the pressure was maintained at 7 bar, the residence time of the reactants was maintained at 1.5 hours, and the polymer mixture was continuously passed to the post reactor while maintaining a constant liquid level in the reactor. .

The post reactor was maintained at 78 ° C. and unreacted monomers were polymerized. The polymerization product was then made into final polyethylene via a solvent removal plant and a dryer. The polyethylene produced was mixed with 1000 ppm of calcium stearate (Dubon Industries) and 2000 ppm of 21B (Songwon Industries) and then made into pellets.

Example  2

A multistage continuous CSTR reactor (see FIG. 1) consisting of two 0.2 m ³ capacity reactors, flash vessels and post reactors was used.

Hexane 31 kg / hr, ethylene 9 kg / hr, hydrogen 4.5 g / hr, nitrogen 0.1 kg / hr, and triethylaluminum (TEAL) were introduced into the first reactor at a flow rate of 30 mmol / hr, respectively. The metallocene supported catalyst prepared at was injected at 1 g / hr (180 μmol / hr). At this time, the first reactor was maintained at 84 ° C., the pressure was maintained at 9 bar, the residence time of the reactants was maintained at 2.5 hours, and the slurry mixture containing the polymer was continuously flashed while maintaining a constant liquid level in the reactor. vessel).

As the slurry mixture was fed into a flash vessel, the gas containing hydrogen, nitrogen, and ethylene was discharged to the outside, and the slurry mixture including the polymer collected in the lower layer was continuously passed to the second reactor.

Into the second reactor, 23 kg / hr of hexane, 6 kg / hr of ethylene, 90 cc / hr of 1-butene and triethylaluminum (TEAL) were injected at a flow rate of 25 mmol / hr, and the molecular weight regulator prepared in Preparation Example 4 was 80 µmol. injected at / hr. The second reactor was maintained at 80 ° C., the pressure was maintained at 7 bar, the residence time of the reactants was maintained at 1.5 hours, and the polymer mixture was continuously passed to the post reactor while maintaining a constant liquid level in the reactor. .

The post reactor was maintained at 78 ° C. and unreacted monomers were polymerized. The polymerization product was then made into final polyethylene via a solvent removal plant and a dryer. The polyethylene produced was mixed with 1000 ppm of calcium stearate (Dubon Industries) and 2000 ppm of 21B (Songwon Industries) and then made into pellets.

Example  3

A multistage continuous CSTR reactor (see FIG. 1) consisting of two 0.2 m ³ capacity reactors, flash vessels and post reactors was used.

Hydrogen was injected into the first reactor at a flow rate of 35 kg / hr of hexane, 10 kg / hr of hydrogen, 0.1 kg / hr of nitrogen, and 40 mmol / hr of triethylaluminum (TEAL) Was injected at a rate of 1 g / hr (180 μmol / hr). At this time, the first reactor was maintained at 84 ° C., the pressure was maintained at 9 bar, the residence time of the reactants was maintained at 2.5 hours, and the slurry mixture containing the polymer was continuously flashed while maintaining a constant liquid level in the reactor. vessel).

As the slurry mixture was fed into a flash vessel, the gas containing hydrogen, nitrogen, and ethylene was discharged to the outside, and the slurry mixture including the polymer collected in the lower layer was continuously passed to the second reactor.

Hexane 21 kg / hr, ethylene 6.5 kg / hr, 1-butene 80 cc / hr, triethylaluminum (TEAL) was injected into the second reactor at a flow rate of 20 mmol / hr, and the molecular weight regulator prepared in Preparation Example 4 Injected at 80 μmol / hr. The second reactor was maintained at 80 ° C., the pressure was maintained at 7 bar, the residence time of the reactants was maintained at 1.5 hours, and the polymer mixture was continuously passed to the post reactor while maintaining a constant liquid level in the reactor. .

The post reactor was maintained at 78 ° C. and unreacted monomers were polymerized. The polymerization product was then made into final polyethylene via a solvent removal plant and a dryer. The polyethylene produced was mixed with 1000 ppm of calcium stearate (Dubon Industries) and 2000 ppm of 21B (Songwon Industries) and then made into pellets.

Comparative example  One

Except that nitrogen was not added in Example 1 was carried out in the same manner as in Example 1.

Comparative example  2

Hexane was 28 kg / hr, ethylene was 7 kg / hr, hydrogen was 3.5 g / hr, and triethylaluminum (TEAL) was injected at a flow rate of 30 mmol / hr, respectively. The catalyst was injected at 0.5 g / hr (180 μmol / hr). At this time, the first reactor was maintained at 84 ° C., the pressure was maintained at 9 bar, the residence time of the reactants was maintained at 2.5 hours, and the slurry mixture containing the polymer was continuously flashed while maintaining a constant liquid level in the reactor. vessel).

The post reactor was maintained at 78 ° C. and unreacted monomers were polymerized. The polymerization product was then made into final polyethylene via a solvent removal plant and a dryer.

[Test Example]

The physical properties of the polyethylene produced or used in Examples 1 to 3 and Comparative Examples 1 and 2 were measured by the following method, and the results are shown in Table 1 below.

* Molecular weight (MW): Measured by weight average molecular weight using Gel Permeation Chromatography (GPC).

* Polydispersity (PDI): The weight average molecular weight was measured by gel permeation chromatography (GPC: Gel Permeation Chromatography) divided by the number average molecular weight.

Melt Index (MI): Measured according to ASTM D1238.

* R1 MI: The slurry in the first reactor was dried to take a polyolefin and measured according to ASTM D1238.

Density: measured according to ASTM D792.

Flexural strength: measured according to ASTM D790.

* Stress crack resistance: Measured according to ISO 16770 under the conditions of temperature 80 ℃, pressure 3.5MPa.

* Die Swell (%): The pelletized product was obtained by cutting the resin when the parison coming out through the blow molding machine (KRUPP KAUTEX, GERMANY) fell 15.7 cm in the vertical direction by measuring its weight.

Die Swell (%) =

As = Vsp × W / L

As: average cross-sectional area of the parison during the shear interval (15.7 cm) (cm ² )

Ad: cross section of die gap (0.6726 cm ² )

Vsp: specific melt volume when polyethylene is not filled

(Specification melting volume) (1.32cm ³ / g)

Sagging time (seconds): The time taken for the molten resin falling in the vertical direction through the blow molding machine to reach the 126.5 cm point.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 polymerization Continuous / multistage Continuous / multistage Continuous / multistage Continuous / multistage Continuous / 1 step Ethylene
(kg / hr) 14 15 16.5 14 7 Nitrogen / First Reactor Ethylene
(g / kg) 12.5 11.1 10 0 - Molecular weight regulator
(μmol) 80 80 80 80 - Copolymer
(cc / hr) 90 90 80 90 - R1 MI (@ 5kg) 300 300 30 300 300 MI (@ 2kg) 0.30 0.38 0.18 1.11 90 MI (@ 5kg) 1.28 1.62 0.88 3.73 300 MI (@ 21.6kg) 34.0 39.2 16.0 71.0 - MFR 110 100 89   64 - MW 262,200 245,500 215,100 165,900 55,000 PDI 17.6 16.6 9.0 12.2 - Density (kg / m ³ ) 0.954 0.955 0.955 0.960 - Flexural strength
(MPa) 1390 1410 1350 1420 - Stress cracking resistance
(FNCT) 40 35 30 5 - Die Swell (%) 200 190 180 150 - Sagging time
(second) 22 22 24 18 - Formability (Appearance) Good Good Good Good -
(Cannot be processed)

As shown in Table 1, the polyethylene according to Examples 1 to 3 of the present invention is very high molecular weight and polydispersity (PDI) compared to the polyethylene of Comparative Examples 1 to 2 prepared without the addition of nitrogen to the first reactor. can confirm. In other words, if the melt index of polyethylene in the first reactor is sufficiently increased and nitrogen is not added at the same time, the activity of the supported metallocene catalyst is not sufficiently maintained in the second reactor. Sustained sufficiently in the second reactor it can be seen that the molecular weight is high and the parison deflection time and stress cracking resistance is improved.

In addition, as shown in Examples 1 to 3 while significantly reducing the molecular weight of the material produced in the first reactor as shown in Comparative Example 2 (MI: 300), the MI or molecular weight of the final product is appropriately adjusted and the polydispersity is Can produce high products.

Example  4: Experiment to verify the effect of nitrogen

The 5 L high pressure reactor was replaced with nitrogen at 60 ° C. for 1 hour, and then 3 L of hexane was added thereto. 1.8 ml of triethylaluminum (1M in hexane) for water removal was injected, and then 30 mg of the catalyst prepared in Preparation Example 3 was suspended in hexane and introduced through a sample vessel connected to the reactor. In addition, the sample vessel connected to the reactor was replaced with nitrogen, and then the valve was opened while filling with 5 ml of nitrogen and 70 ml, and then charged into the reactor. Thereafter, ethylene was continuously added at 30 ° C. and polymerized for 2.5 hours while maintaining a pressure of 9 bar. The temperature was lowered to 40 ° C., the ethylene and nitrogen in the reactor were removed and the reactor temperature was raised to 70 ° C. again. Ethylene was continuously added to the reactor and polymerized for 1.5 hours while maintaining a pressure of 9 bar. The temperature was then lowered, the internal gas removed, separated and dried. The graph shows the time-input and cumulative input amount of ethylene for this in units of ml and is shown in FIG. 2.

Comparative example  3: Experiment to verify the effect of nitrogen

Example 4 was carried out in the same manner as in Example 4 except that nitrogen was not added to the reactor through the sample vessel. The graph shows the time-input and cumulative input amount of ethylene for this in units of ml and is shown in FIG. 2.

As shown in FIG. 2, when a multi-stage reaction is performed by initially adding an inert gas, it can be seen that the catalyst absorbs ethylene unilaterally and converts it into polyethylene in the first stage reaction, and thus the catalyst activity is continuously maintained in the two stage reaction. You can see that. However, if the nitrogen is not added, the catalyst rapidly absorbs ethylene in the first stage reaction, so that the activity is not sustained in the two stage reaction and less ethylene is absorbed.

Claims (20)

A method for producing polyethylene by reacting an ethylene monomer with a catalyst in a reactor in which a first reactor and a second reactor are connected in series,
(i) reacting the catalyst with the ethylene monomer in the presence of a metallocene supported catalyst and an inert gas in a first reactor to produce a low molecular weight ethylene polymer;
(ii) delivering a slurry mixture comprising the low molecular weight ethylene polymer to a flash vessel to evacuate gas; And
(iii) reacting the slurry mixture and ethylene monomer in the presence of a molecular weight modifier in a second reactor to produce a high molecular weight ethylene polymer;
Method for producing a polyethylene resin, characterized in that it comprises. The method of claim 1,
The inert gas is a method for producing a polyethylene resin, characterized in that nitrogen. The method of claim 1,
The weight ratio of the inert gas and ethylene is 1:10 to 1: 100 method of producing a polyethylene resin. The method of claim 1,
The inert gas is a method of producing a polyethylene resin, characterized in that the mixed gas further comprises 0 to 5% by weight of hydrogen. The method of claim 1,
The metallocene supported catalyst is a mixed metallocene supported catalyst comprising a carrier, a first metallocene compound, a second metallocene compound, a first cocatalyst, and a second cocatalyst. Manufacturing method. 6. The method of claim 5,
The carrier is a method of producing a polyethylene resin, characterized in that selected from the group consisting of silica, silica-alumina and silica-magnesia. 6. The method of claim 5,
The first cocatalyst is a method for producing a polyethylene resin, characterized in that the aluminum-containing organometallic compound represented by the formula (1).
[Formula 1]
-[Al (R ¹ ) -O-] _n-
In Formula 1, R ¹ is the same or different halogen radicals, C1-C20 hydrocarbyl radicals or C1-C20 hydrocarbyl radicals substituted with halogen, n is an integer of 2 or more. 6. The method of claim 5,
The second cocatalyst is a boron-containing borate compound represented by the following formula (2).
(2)
T ⁺ [BQ ₄ ] ^-
In Formula 2, T ⁺ is a + monovalent polyatomic ion, B is boron in a +3 type oxidation state, and Q is independently hydride, dialkylamido, halide, alkoxide, aryloxide, hydrocarbyl, halo It is selected from carbyl and halo-substituted hydrocarbyl radicals, wherein Q has up to 20 carbons, but at less than one position Q is a halide. 6. The method of claim 5,
The first metallocene compound is a compound represented by the following Chemical Formula 3, and the second metallocene compound is a compound represented by the following Chemical Formula 4;
(3)

[Chemical Formula 4]

In Formulas 3 and 4, R ^m , R ⁿ are the same or different hydrogen radicals, alkyl having 1 to 20 carbon atoms, cycloalkyl, aryl, alkenyl, alkylaryl, arylalkyl, arylalkenyl radicals or alkylsilyl radicals , R ¹ and R ² are the same or different hydrogen or a hydrocarbyl radical of 1 to 6 carbon atoms, a, a ', b or b' are each an integer of 1 to 4,
M is a transition metal of Groups 4B, 5B, or 6B of the periodic table, and Q is a halogen radical or an alkyl radical of 1 to 20 carbon atoms, an alkenyl radical, an aryl radical, an alkylaryl radical, an arylalkyl radical, or 1 to 20 carbon atoms Alkylidene radicals,
B is any one selected from the group consisting of alkyl radicals having 1 to 4 carbon atoms or hydrocarbyl radicals containing silicon, germanium, phosphorus, nitrogen, boron or aluminum,
J is any one selected from the group consisting of NR ⁵ , O, PR ⁵ and S, wherein R ⁴ is an alkyl radical or substituted alkyl radical of 1 to 20,
Provided that any hydrogen radical present in R ^m , R ⁿ , B or R ⁵ is alkoxy, aryloxy, alkylthio, arylthio, amino, phenyl or substituted phenyl having 1 to 20 carbon atoms or having 1 to 20 carbon atoms Alkoxy. The method of claim 1,
Into the first reactor or the second reactor, an organoaluminum compound selected from the group consisting of trialkylaluminum, dialkyl aluminum halides, alkyl aluminum dihalides, aluminum dialkyl hydrides and alkyl aluminum sesqui halides is further added to the water in the reactor. Method of producing a polyethylene resin, characterized in that for removing. The method of claim 1,
The molecular weight modifier is a method for producing a polyethylene resin, characterized in that the organometallic complex prepared by reacting the cyclopentadienyl metal compound represented by the formula (5) and the organoaluminum compound represented by the formula (6).
[Chemical Formula 5]
Cp ¹ Cp ² MX ₂
In Formula 5, Cp ¹ and Cp ² are independently a pentacyclopentadienyl, indenyl group, fluorenyl group, or a derivative thereof, M is titanium, zirconium or hafnium, and X is a halogen element.
[Chemical Formula 6]
R ¹ R ² R ³ Al
In Formula 6, R ¹ , R ^2, or R ³ are independently C ¹ -C 20 alkyl substituents or halogen. 12. The method of claim 11,
The content of the molecular weight regulator is a polyethylene resin production method, characterized in that the M content of the organometallic complex compound of 0.001μmol · 1kg to 10μmol · 1kg based on 1kg of total ethylene injected into the entire reactor. The method of claim 1,
Method for producing a polyethylene resin, characterized in that further adding a comonomer to the second reactor. The method of claim 1,
The residence time of the polymerization process in the first reactor is a method for producing a polyethylene resin, characterized in that 1 to 3 hours. The method of claim 1,
Method of producing a polyethylene resin, characterized in that the residence time of the polymerization process in the second reactor is 1 to 3 hours. The method of claim 1,
The reaction temperature of the polymerization process of the first reactor is 70 to 90 ℃, the reaction pressure is a method for producing a polyethylene resin, characterized in that 8 to 10bar. The method of claim 1,
The reaction temperature of the polymerization process of the second reactor is 60 to 90 ℃, the reaction pressure is a method for producing a polyethylene resin, characterized in that 6 to 9 bar. The method of claim 1,
The flash vessel is composed of a valve of the first reactor adjusted to 9bar or more and a valve of the second reactor controlled to 7bar or more, the temperature is 70 to 90 ℃, the time required for the gas discharge is 5 to 30 minutes Method for producing a polyethylene resin, characterized in that. The method of claim 1,
The weight average molecular weight of the low molecular weight polyethylene is 10,000 to 100,000, the polydispersity is 1.5 to 5.0, the melt index is 5kg, the manufacturing method of polyethylene resin, characterized in that 1000 to 10 at 190 ℃ conditions. The method of claim 1,
The weight average molecular weight of the high molecular weight polyethylene is 150,000 to 300,000, the polydispersity is 5 to 20, the melt index is 5kg, the manufacturing method of polyethylene resin, characterized in that 10 to 0.1 at 190 ℃ conditions.

Images