KR100787659B1 - A method for ethylene polymerization and co-polymerization - Google Patents

Abstract

The present invention relates to a ethylene polymerization or copolymerization method, characterized in that the polymerization or copolymerization of ethylene in the presence of the following (a) and (b): (a) prepared by the production method comprising the following steps Preactivated solid complex titanium catalyst; (i) contacting a magnesium halide compound with an alcohol to prepare a magnesium compound solution; (ii) reacting the magnesium compound solution with a compound having a phthalic group represented by formula (I), an ester compound having at least one hydroxyl group, and a silicon compound having an alkoxy group represented by formula (II); (iii) adding a mixture of a titanium compound and a silicon compound to the reactant to recrystallize the catalyst to produce a solid complex titanium catalyst; (iv) preactivating the solid complex titanium catalyst with a poly (hydrobakyl-aluminum oxide) compound; And (b) Group II or III organometallic compounds and haloalkane compounds of the periodic table.

Titanium Catalysts, Preactivated, Poly (hydrobakyl-Aluminum Oxide) Compounds, Haloalkanes Compounds

Description

Ethylene polymerization and copolymerization method {A METHOD FOR ETHYLENE POLYMERIZATION AND CO-POLYMERIZATION}

The present invention relates to a process for producing an ethylene polymer or copolymer (hereinafter simply referred to as a polymer). More particularly, the present invention relates to a method for producing a polymer having high apparent yield, narrow molecular weight distribution, and high molecular weight tail.

As is known, many processes and catalysts have been developed for polymerization and copolymerization. In particular, production of polymers and copolymers having a high average molecular weight and exhibiting a narrow molecular weight distribution for application in various fields is required. Polymers and copolymers having high average molecular weight and narrow molecular weight distribution properties have the advantage of having good mechanical properties.

Catalysts for ethylene polymerization and copolymerization containing magnesium are known to exhibit very high catalytic activity and are also suitable for liquid and gas phase polymerization. Ethylene liquid phase polymerization refers to a polymerization process performed in a solvent such as bulk ethylene, isopentane, and hexane, and the catalyst used therein requires high activity. In addition, the molecular weight distribution is an important variable for determining the physical properties of the ethylene polymer, and particularly, the ethylene polymer having a narrow molecular weight distribution is an important property which is very advantageous for injection-molded products.

Increasing the molecular weight of the polymer to be prepared, there is an advantage that the tensile strength is increased, but there is a problem such as cracking during processing due to poor workability. In order to overcome this problem, a high molecular weight tail may be introduced into the molecular weight distribution while increasing the molecular weight. In particular, a method of introducing a high molecular weight tail is an ideal method because it does not significantly affect workability while increasing the tensile strength.

Many catalysts and catalyst preparation processes for olefin polymerization, including magnesium and based on titanium, have been reported. In particular, many methods using a magnesium solution are known in order to obtain a catalyst for olefin polymerization having a high apparent density of the polymer. There is a method of obtaining a magnesium solution by reacting a magnesium compound with an electron donor such as an alcohol, an amine, a cyclic ether or an organic carboxylic acid in the presence of a hydrocarbon solvent. Among these, the use of alcohols is mentioned in US Pat. Nos. 4,330,649 and 5,106,807. In addition, a method of preparing a magnesium supported catalyst by reacting the liquid magnesium solution with a halogen-containing compound such as tetrachlorotitanium is well known. In addition, attempts have been made to control polymerization activity and molecular weight distribution by adding compounds of esters. Such a catalyst provides a polymer with a high apparent density, but there is a need to be improved in terms of the activity of the catalyst or the molecular weight distribution of the polymer.

U.S. Patent No. 5,459,116 reports a method for preparing a titanium solid catalyst supported by a magnesium reaction comprising a ester compound having at least one hydroxy group as an electron donor and a titanium compound. Using this method, a catalyst having excellent polymerization activity and apparent density can be obtained, but there is a point to be improved in terms of molecular weight distribution of the polymer.

As indicated above, it is not easy to control the molecular weight distribution of polymers while maintaining high catalytic activity and apparent density of the polymers as a conventional Ziegler-Natta type catalyst, requiring complicated catalyst preparation processes or difficult polymerization processes. There is a difficulty. However, in order to improve the use expansion, processability, physical properties, and the like of the ethylene polymer, control of the molecular weight distribution is required.

The present invention proposes a polymerization method of an ethylene polymer having a narrow molecular weight distribution and showing a high molecular weight tail while maintaining a high catalytic activity and an apparent density of the polymer by a simple and easy method.

In order to solve the above problems, an object of the present invention is to provide a polymerization method of the ethylene polymer having a narrow molecular weight distribution and high molecular weight tail while having a high polymerization activity of the catalyst and the apparent density of the produced ethylene polymer.

The ethylene polymerization or copolymerization method of the present invention is characterized by polymerizing or copolymerizing ethylene in the presence of the following (a) and (b).

(a) a preactivated solid complex titanium catalyst prepared by a process comprising the following steps;                     

(i) contacting a magnesium halide compound with an alcohol to prepare a magnesium compound solution;

(ii) reacting the magnesium compound solution with a compound having a phthalic group represented by formula (I), an ester compound having at least one hydroxyl group, and a silicon compound having an alkoxy group represented by formula (II); And

C ₆ H ₄ -1- [CO ₂ -R] -a- [CO ₂ -R ′]

[Wherein R and R ′ are hydrocarbons having 1 to 20 carbon atoms and are alkyl, isoalkyl, tertiaryalkyl, alkenyl or aryl, may or may not be the same as each other and a is 2, 3 or 4 Is a natural number of

R _n Si (OR ′) _4-n

[Wherein R and R ′ are hydrocarbons having 1 to 12 carbon atoms and n is a natural number of 0 to 3;

(iii) adding a mixture of a titanium compound and a silicon compound to the reactant to recrystallize the catalyst to produce a solid complex titanium catalyst;

(iv) preactivating the solid complex titanium catalyst with a poly (hydrobakyl-aluminum oxide) compound; And

(b) Group II or III organometallic compounds and haloalkane compounds of the periodic table.

In the method for preparing the titanium catalyst (a) used in the ethylene polymerization or copolymerization method of the present invention, the method further comprises the step of reacting the solid complex titanium catalyst obtained in step (iii) with the titanium compound before preactivation (iv). can do.

The present invention is described in more detail as follows.

In step (i) of the method for preparing the titanium catalyst (a) used in the present invention, the magnesium compound solution may be prepared as a solution by reacting the magnesium halide compound with alcohol in the presence or absence of a hydrocarbon solvent.

The magnesium halide compounds include magnesium halides such as magnesium chloride, magnesium iodide, magnesium fluoride and magnesium bromide; Alkylmagnesium halides such as methylmagnesium halide, ethylmagnesium halide, propylmagnesium halide, butylmagnesium halide, isobutylmagnesium halide, hexylmagnesium halide and amylmagnesium halide; Alkoxymagnesium halides such as methoxymagnesium halide, ethoxymagnesium halide, isopropoxymagnesium halide, butoxymagnesium halide and octoxymagnesium halide; Or aryloxymagnesium halides such as phenoxymagnesium halide and methylphenoxymagnesium halide. In addition, a mixture of two or more of the above magnesium compounds or a complex with another metal may be included. However, the magnesium halide compound used in the present invention is not limited to these examples.

The hydrocarbon solvent includes aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane and kerosene; Alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane and methylcyclohexane; Or aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene and cymene.                     

In addition, the alcohol includes 1 to 20 such as methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, decanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenyl alcohol, isopropyl benzyl alcohol and cumyl alcohol. Alcohols containing 3 carbon atoms may be included, and preferably 1 to 12 carbon atoms. The total amount of alcohol may be used in the range of about 2.0 moles to 10 moles per mole of the magnesium compound. Although the melting temperature of the said magnesium compound changes with kinds of alcohol, it is about 0 degreeC-150 degreeC, and dissolution time is about 15 minutes-10 hours, Preferably it is about 2 hours-6 hours.

In step (ii) of the method for preparing the titanium catalyst (a) used in the present invention, the compound having a phthalic group used as the electron donor is represented by the following general formula (I).

C ₆ H ₄ -1- [CO ₂ -R] -a- [CO ₂ -R ′]

Here, R and R 'are hydrocarbons having 1 to 20 carbon atoms, and are alkyl, isoalkyl, tertiaryalkyl, alkenyl or aryl and the like, which may or may not be the same. a is a natural number of 2, 3 or 4.

Specific examples of the compound include dimethyl phthalate, diethyl phthalate, dipropyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, diallyl phthalate, dicyclohexyl phthalate, benzyl butyl phthalate, diphenyl phthalate, and dimethyl. Although isophthalate, diphenyl isophthalate, dimethyl terephthalate, and dioctyl terephthalate are included, it is not limited to this, Any compound can be included as long as it satisfy | fills the said general formula, A mixture of these compounds can also be used. The amount of the compound used is preferably 0.02 mol to 0.5 mol per mol of the magnesium compound, more preferably 0.05 mol to 0.2 mol per mol.

In step (ii) of the method for preparing the titanium catalyst (a) used in the present invention, the ester compound including at least one hydroxy group used as the electron donor is 2-hydroxy ethyl acrylate, 2-hydroxy ethyl Unsaturated fatty acid esters comprising at least one hydroxy group such as methacrylate, 2-hydroxypropyl acrylate, 2-hydroxy propylmethacrylate, 4-hydroxy butylacrylate and pentaerythritol triacrylate; 2-hydroxy ethyl acetate, methyl 3-hydroxy butyrate, ethyl 3-hydroxy butyrate, methyl 2-hydroxy isobutyrate, ethyl 2-hydroxy isobutyrate, methyl-3-hydroxy-2-methyl propionate , 2,2-dimethyl-3-hydroxy propionate, ethyl-6-hydroxy hexanoate, t-butyl-2-hydroxy isobutyrate, diethyl-3-hydroxy glutarate, ethyl lactate , Isopropyl lactate, butyl isobutyl lactate, isobutyl lactate, ethyl mandelate, dimethyl ethyl tartrate, ethyl tartrate, dibutyl tartrate, diethyl citrate, triethyl citrate, ethyl 2-hydroxy Aliphatic monoesters or polyesters containing at least one hydroxy group such as caproate and diethyl bis- (hydroxy methyl) malonate; 2-hydroxy ethyl benzoate, 2-hydroxy ethyl salicylate, methyl 4- (hydroxy methyl) benzoate, methyl 4-hydroxy benzoate, ethyl 3-hydroxy benzoate, 4-methyl salicyl Ethyl salicylate, phenyl salicylate, propyl 4-hydroxy benzoate, phenyl 3-hydroxy naphtanoate, monoethylene glycol monobenzoate, diethylene glycol monobenzoate and triethylene glycol monobenzoate Aromatic esters containing at least one hydroxy group, such as; Or alicyclic esters containing at least one hydroxy group such as hydroxy butyl lactone. The amount of the ester compound including at least one hydroxy group is 0.001 to 5 mol per mol of magnesium, preferably 0.01 to 2 mol per mol.

In step (ii) of the method for preparing the titanium catalyst (a) used in the present invention, the silicon compound having an alkoxy group used as another electron donor is represented by the following general formula (II).

R _n Si (OR ′) _4-n

Here, R and R 'are hydrocarbons having 1 to 12 carbon atoms, and n is a natural number of 0 to 3.

Examples of the compound that satisfies the general formula (II) include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, ethyltrimethoxysilane, vinyltrimethoxysilane, methyltrimeth Methoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, phenyltriethoxysilane, ethyltriisopropoxysilane, vinyltributoxy Silanes, ethyl silicates, butyl silicates, methyltriaryloxysilanes, and the like. The amount of the compound to be used is preferably 0.05 to 3 mol per mol of magnesium, more preferably 0.1 to 2 mol per mol.

In the step (ii) of the method of preparing the titanium catalyst (a) used in the present invention, a magnesium compound solution is contacted with a compound having a phthalic group, an ester compound including at least one hydroxy group, and a silicon compound having an alkoxy group. The temperature is preferably 0 ° C to 100 ° C, more preferably 10 ° C to 100 ° C.

In the method of preparing the titanium catalyst (a) used in the present invention, in step (iii), the magnesium compound solution obtained in step (ii) is reacted with a mixture of a titanium compound and a silicon compound in a liquid state to recrystallize the catalyst particles to obtain a solid. Prepare the complex titanium catalyst.

The titanium compound may be represented by the following general formula (III).

Ti (OR) _a X _4-a

Here, R is an alkyl group having 1 to 10 carbon atoms, X is a halogen atom, and a is an integer of 0 to 4. Examples of compounds satisfying the general formula (III) include titanium tetrahalides such as TiCl ₄ , TiBr ₄ and TiI ₄ ; Trihalogenated alkoxytitanium such as Ti (OCH ₃ ) Cl ₃ , Ti (OC ₂ H ₅ ) Cl ₃ , Ti (OC ₂ H ₅ ) Br ₃ and Ti (O (iC ₄ H ₉ )) Br ₃ ; Dihalogenated alkoxytitanium such as Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (O (iC ₄ H ₉ )) ₂ Cl ₂ and Ti (OC ₂ H ₅ ) ₂ Br ₂ ; Or tetraalkoxytitanium such as Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ and Ti (OC ₄ H ₉ ) ₄ . Also mixtures of compounds selected from these may be included. Preferred titanium compounds are halogen-containing titanium compounds, more preferably tetrachlorotitanium.

The silicone compound may be represented by the following general formula (IV).

R _n SiCl _4-n ................................... (IV)

Here, R is hydrogen or an alkyl, alkoxy, haloalkyl, aryl group having 1 to 10 carbon atoms or a halosilyl or halosilylalkyl group having 1 to 8 carbon atoms, and n is an integer of 0 to 3;

Examples of the compound satisfying the general formula (IV) include tetrachlorosilicon; Trichlorosilanes such as methyltrichlorosilane, ethyltrichlorosilane and phenyltrichlorosilane; Dichlorosilanes such as dimethyldichlorosilane, diethyldichlorosilane, diphenyldichlorosilane and methylphenyldichlorosilane; Or monochlorosilanes such as trimethylchlorosilane. Also included are mixtures of the above silicone compounds. Preferred silicone compounds are tetrachlorosilicones.

The amount of the mixture of the titanium compound and the silicon compound is preferably 0.1 to 200 moles per mole of magnesium compound, more preferably 0.1 to 100 moles, and most preferably 0.2 to 80 moles. The mixing ratio of the titanium compound and the silicon compound is preferably 0.05 to 0.95 in molar ratio, and more preferably 0.1 to 0.8. The reaction of the magnesium compound solution with the mixture of the titanium compound and the silicon compound is preferably carried out at a sufficiently low temperature to recrystallize the catalyst particles. This is because the shape and size of the solid component recrystallized according to the reaction conditions greatly affect the apparent density of the polymer. Preferably, the reaction is carried out at -70 ° C to 70 ° C, more preferably at -50 ° C to 50 ° C. After the contact reaction, the reaction temperature was gradually raised to react for 0.5 hours to 5 hours at 50 ° C to 150 ° C.

Furthermore, the solid complex titanium catalyst obtained in step (iii) of the method for preparing the titanium catalyst (a) used in the present invention may be further reacted with the titanium compound. Herein, the titanium compound may be represented by the general formula Ti (OR) _a X _4-a (R is an alkyl group having 1 to 10 carbon atoms, X is a halogen atom and a is an integer of 0 to 4). Compound. Preferably, the halogenated alkoxy titanium having a titanium halide and an alkoxy functional group having 1 to 10 carbon atoms, more preferably titanium tetrahalide. The use amount of the titanium compound is preferably 1 mol to 20 mol, more preferably 1 mol to 10 mol, per mol of the magnesium compound. The reaction is preferably carried out at 40 ℃ to 150 ℃ for 0.5 hours to 5 hours.

The solid titanium catalyst component prepared in step (iii) of the method for preparing the titanium catalyst (a) used in the present invention is preactivated by a poly (hydrobakyl-aluminum oxide) compound. The preactivation reaction of the solid titanium catalyst component may be achieved by contacting the solid titanium catalyst component with a poly (hydrobakyl-aluminum oxide) compound and then reacting for a predetermined time. The contact can be made by conventional mixing means, for example by stirring with a stirrer.

The poly (hydrobakyl-aluminum oxide) (also referred to as alkyl aluminoxane) compound used in the above preactivation reaction has a repeating unit represented by the following general formula (V), and has a linear, branched or cyclic oligomeric form. Poly (hydrobakyl-aluminum oxide).

-(Al (R) O)-ㆍ ‥‥‥ (V)

Wherein R is hydrogen, an alkyl group containing from 1 to 12 carbon atoms or a substituted or unsubstituted phenyl or naphthyl group. Specific examples are methylaluminoxane or modified methylaluminoxane. The preparation of aluminoxane is well known from previous studies. In the poly (hydrobakyl-aluminum oxide), the linear one is 1 to 40 repeating units of the general formula (V), more preferably 1 to 20 is repeated, the cyclic is 3 to 40, more preferably 3 to 20 is good to repeat. The poly (hydrobakyl-aluminum oxide) compound is preferably used in an amount of 0.1 mol to 20 mol of aluminum atoms per mol of titanium atoms in the catalyst, and more preferably at a ratio of 1 mol to 10 mol. The reaction temperature is preferably carried out at -50 ° C to 50 ° C, more preferably at -20 ° C to 30 ° C. After the contact reaction, the reaction temperature is gradually raised and reacted at 0 ° C. to 150 ° C. for 0.5 hours to 5 hours.

The periodic table group II or group III organometallic compound (b) used in the present invention is used as a promoter for the polymerization reaction in the present invention, and may be represented by the general formula MR _n (VI). Wherein M is a periodic table of Group II or Group IIIA metal components such as magnesium, calcium, zinc, boron, aluminum and gallium, and R is 1-20 carbon atoms such as methyl, ethyl, butyl, hexyl, octyl and decyl It is an alkyl group, n is the valence of a metal component. Among the compounds satisfying the above general formula, trialkylaluminums having 1 to 6 carbon atoms, such as triethylaluminum and triisobutylaluminum, and mixtures thereof are more preferable. In some cases, organoaluminum compounds comprising at least one halogen or hydride group such as ethylaluminum dichloride, diethylaluminum chloride, ethylaluminum sesquichloride and diisobutylaluminum hydride may also be used.

Haloalkane compounds used in the present invention is ethyl chloride, dichloromethane, dichloroethane, chloroform, One or more halogens of chlorine, bromine, fluorine or iodine, such as tertiary butyl chloride, tetrachloromethane, phenyl chloride, ethyl bromide, tertiary butyl iodide, normal butyl bromide, normal butyl iodide and normal butyl fluoride It is possible to use a compound having 1 to 10 carbon atoms or a mixture thereof. The haloalkane compound exhibited the best effect in terms of catalyst activity and molecular weight distribution when injected at a molar ratio of 0.5 to 50, more preferably 1 to 30, relative to the titanium atom of the catalyst to be injected into the reaction system.

The present invention is characterized by polymerizing or copolymerizing ethylene in the presence of the preactivated solid complex titanium catalyst (a) and the organometallic compound of the Group II or Group III of the periodic table and the haloalkane compound (b). The copolymerizable monomer may be an α-olefin having 3 or more carbon atoms such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, and 1-hexene.

The polymerization of the present invention can be either a gas phase or bulk polymerization performed without an organic solvent, or a liquid phase slurry polymerization method carried out in the presence of an organic solvent.

In the case of gas phase polymerization, the amount of catalyst (preactivated solid complex titanium catalyst) in the reaction system is about 0.001 to 5 mmol, preferably about 0.001 to 1.0 mmol, more preferably, based on the titanium atom of the catalyst per 1 liter of polymerization volume. Is preferably about 0.01 to 0.5 mmol. Preferred concentrations of the organometallic compounds used as cocatalysts are from about 1 to 2,000 moles per mole of titanium atoms in the catalyst calculated on the basis of organometallic atoms (eg aluminum atoms), more preferably from about 5 to 500 The mall is beneficial.

In the case of liquid slurry polymerization, nonpolar organic solvents such as alkanes (eg, hexane, normal heptane, octane, nonane, decane) and alicyclic compounds (eg, cycloalkane) may be used as the organic solvent. Preferably hexane is preferred. It should be purified before use to not affect catalytic activity. The concentration of the preferred solid complex titanium catalyst on the polymerization reaction system is about 0.001 to 5 mmol, preferably about 0.001 to 0.5 mmol, of titanium atoms of the catalyst per 1 liter of solvent. The preferred amount of organometallic compound to be used as a cocatalyst is about 1 to 2,000 moles per mole of titanium atoms in the catalyst calculated on the basis of organometallic atoms (eg aluminum atoms), and more preferably about 5 to about 500 moles is advantageous.

The temperature of the polymerization reaction is preferably about 20 to 200 ° C, more preferably 20 to 95 ° C. The pressure of the monomer is preferably from atmospheric pressure to 100 atmospheres, more preferably from 2 to 50 atmospheres.

The well-known method of controlling the molecular weight of the polymer through the hydrogen injection amount can be used. The molecular weight is represented by the melt index (ASTM D 1238), which is commonly known in the art. Generally, the lower the molecular weight, the larger the value. The molecular weight distribution of the polymer was obtained by measuring GPC (Gel Permeation Chromatography), the measurement method of which was commonly used in the art. The molecular weight distribution was expressed in Mw / Mn, and the degree of high molecular weight tail was expressed in Mz / Mw. In general, the higher the Mz / Mw value, the higher the molecular weight tail is known to be.

The present invention will be described in more detail with reference to the following examples and comparative examples. However, these examples are for illustrative purposes only, and the present invention is not limited to these examples.

Example

Example 1

Preparation of Preactivated Catalyst

The solid complex titanium catalyst component was prepared through the following steps.

(i) step: preparation of magnesium solution

9.5 g of MgCl ₂ and 500 ml of heptane were added and stirred at 500 rpm in a 1 liter reactor equipped with a mechanical stirrer in a nitrogen atmosphere. The homogeneous solution obtained after the reaction was cooled to room temperature.

(ii) step: a catalytic reaction between a magnesium solution and a compound having a phthalic group, an ester compound having at least one hydroxy group and a silicon compound having an alkoxy group

To the magnesium solution cooled to 70 ° C., 4.6 ml of diisobutyl phthalate, 1.2 ml of 2-hydroxyethyl methacrylate, and 10.0 ml of ethyl silicate were added and reacted for 1 hour.

(iii) step: treatment of mixed solution of titanium compound and silicon compound

The solution prepared in step (ii) was adjusted to room temperature, and a mixed solution of 90 ml of tetrachlorotitanium and 90 ml of tetrachlorosilicon was added dropwise for 2 hours. When the dropping was completed, the temperature of the reactor was raised to 80 ° C. over 1 hour and maintained for 1 hour. The reactor was cooled to room temperature, the stirring was stopped and the solution of the upper layer was separated and washed by injecting 400 ml of hexane until the unreacted free tetrachlorotitanium was removed. The titanium content of the prepared solid catalyst was 4.0%.

(iv) preactivation of the catalyst

The solid titanium catalyst prepared above was subdivided into 200 ml of hexane slurry so as to be 6 mmol / l based on the titanium atom. The temperature of the solid titanium catalyst hexane slurry solution was lowered to 0 ° C., and 3.29 ml of a solution in which 10% methylaluminoxane was dissolved in toluene was slowly added to toluene while stirring. After the injection was complete the solution temperature was raised to 20 ° C. and stirred for 5 hours to preactivate the solid titanium catalyst component. After 5 hours, stirring was terminated and stored at -10 ° C.

polymerization

The 2-liter high pressure reactor was dried in an oven and then assembled hot. Nitrogen and vacuum were operated three times in alternation to bring the reactor into a nitrogen atmosphere. 1,000 ml of dry normal hexane was injected into the reactor, 3 mmol of triisobutylaluminum and 0.12 mmol of ethyl chloride were sequentially injected, followed by 0.03 mmol of the preactivated solid titanium catalyst component, and 1,000 ml of hydrogen. . The stirrer was fixed at 700 rpm to operate, the temperature of the reactor was raised to 80 ° C., the ethylene pressure was adjusted to 80 psi, and polymerization was carried out for one hour. After completion of the polymerization, the temperature of the reactor was lowered to room temperature, and an excess ethanol solution was added to the polymerization contents to terminate the reaction. The resulting polymer was collected by filtration through a filter and dried for at least 6 hours in a vacuum oven at 50 ° C.

Polymerization activity (kg polyethylene / g catalyst) was calculated as the weight (kg) ratio of the resulting polymer per gram of catalyst used. The polymerization results are shown in Table 1 together with the melt index (g / 10 min), the molecular weight distribution (Mw / Mn), and the degree of expression of the high molecular weight tail (Mz / Mw).

Example 2

In the catalyst pre-activation process (iv) of Example 1, the injection amount of the solution in which 10% methylaluminoxane was dissolved was 6.58 ml. The polymerization was carried out by the method of Example 1, and the polymerization results are shown in Table 1.

Example 3

In the catalyst preactivation process (iv) of Example 1, the injection amount of the solution in which 10% methylaluminoxane was dissolved was set to 9.87 ml. The polymerization was carried out by the method of Example 1, and the polymerization results are shown in Table 1.

Example 4

The polymerization was carried out by injecting 0.24 mmol of ethyl chloride during the polymerization of Example 1, and the results are shown in Table 1.

Example 5

In the polymerization of Example 1, 0.36 mmol of ethyl chloride was injected to carry out polymerization, and the results are shown in Table 1.

Example 6

The polymerization was carried out by injecting 0.12 mmol of tertiary butyl chloride instead of ethyl chloride in the polymerization process of Example 1, and the results are shown in Table 1.

Example 7

Polymerization was carried out by injecting 0.12 mmol of dichloroethane instead of ethyl chloride during the polymerization of Example 1, and the results are shown in Table 1.

Example 8

Polymerization was carried out by injecting 0.12 mmol of dichloromethane instead of ethyl chloride during the polymerization of Example 1, and the results are shown in Table 1.

Example 9

The polymerization was carried out by injecting 0.12 mmol of phenyl chloride instead of ethyl chloride in the polymerization process of Example 1, and the results are shown in Table 1.

Comparative Example 1

In Example 1, the catalyst preactivation step (iv) was omitted, and polymerization was performed without injecting ethyl chloride during the polymerization process. The polymerization results are shown in Table 1.

Comparative Example 2

In Example 1, the catalyst preactivation step (iv) was omitted and polymerization was carried out. The polymerization results are shown in Table 1.

Comparative Example 3

The polymerization was carried out without injecting ethyl chloride during the polymerization process of Example 1. The polymerization results are shown in Table 1.

Table 1. Polymerization Experiment Results

activation Apparent density Melt Index (MI) Molecular Weight Distribution (Mw / Mn) Expression level of high molecular weight tail (Mz / Mw) KgPE / g catalyst g / ml g / 10min Example 1 4.9 0.39 3.30 6.5 9.1 Example 2 4.4 0.36 2.19 7.7 9.3 Example 3 4.2 0.30 1.85 9.1 9.3 Example 4 5.2 0.37 3.41 6.7 9.7 Example 5 5.7 0.36 3.60 6.9 9.9 Example 6 4.3 0.38 3.17 6.5 8.4 Example 7 4.5 0.39 3.09 6.8 9.3 Example 8 4.3 0.37 3.11 7.0 8.8 Example 9 4.1 0.37 3.20 7.0 8.5 Comparative Example 1 4.0 0.39 3.57 6.5 5.3 Comparative Example 2 4.2 0.39 3.62 6.7 5.9 Comparative Example 3 4.0 0.37 2.72 7.0 6.1

According to the method of the present invention, it is possible to prepare an ethylene polymerization and copolymer having a narrow molecular weight distribution and showing a high molecular weight tail while maintaining a high catalyst activity and an apparent density of the polymer by a simple and easy method.

Claims (15)

Ethylene polymerization or copolymerization method characterized by polymerizing or copolymerizing ethylene in the presence of the following (a) and (b): (a) a preactivated solid complex titanium catalyst prepared by a process comprising the following steps; (i) contacting a magnesium halide compound with an alcohol to prepare a magnesium compound solution; (ii) reacting the magnesium compound solution with a compound having a phthalic group represented by formula (I), an ester compound having at least one hydroxyl group, and a silicon compound having an alkoxy group represented by formula (II); And C ₆ H ₄ -1- [CO ₂ -R] -a- [CO ₂ -R ′] [Wherein R and R ′ are hydrocarbons having 1 to 20 carbon atoms and are alkyl, isoalkyl, tertiaryalkyl, alkenyl or aryl, may or may not be the same as each other, and a is 2, 3 or Is a natural number of 4.] R _n Si (OR ′) _4-n [Wherein R and R ′ are hydrocarbons having 1 to 12 carbon atoms and n is a natural number of 0 to 3; (iii) adding a mixture of a titanium compound and a silicon compound to the reactant to recrystallize the catalyst to produce a solid complex titanium catalyst; (iv) preactivating the solid complex titanium catalyst with a poly (hydrobakyl-aluminum oxide) compound; And (b) Group II or III organometallic compounds and haloalkane compounds of the periodic table. The ethylene polymerization or copolymerization method according to claim 1, further comprising the step of reacting the solid complex titanium catalyst obtained in step (iii) with a titanium compound before preactivating. According to claim 1 or 2, wherein the poly (hydrobakyl-aluminum oxide) compound has a repeating unit of the general formula (V) below, poly (hydrobakyl- in the form of a linear, branched or cyclic oligomer Aluminum oxide). -(Al (R) O)-ㆍ ‥‥‥ (V) [Where R is hydrogen or an alkyl group containing 1 to 12 carbon atoms, a substituted or unsubstituted phenyl group or a naphthyl group.] The ethylene polymerization or copolymerization according to claim 3, wherein the linear one of the poly (hydrobakyl-aluminum oxide) has 1 to 40 repeating units of the general formula (V) and the 3 to 40 repeating ones of the cyclic form. Way. The method of claim 3, wherein the poly (hydrobakyl-aluminum oxide) compound is methylaluminooxane or modified methylaluminooxane. According to claim 1 or 2, wherein the compound having a phthalic group is dimethyl phthalate, diethyl phthalate, dipropyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, diallyl phthalate, dicyclohexyl phthalate, Ethylene polymerization or copolymerization method characterized in that the benzyl butyl phthalate, diphenyl phthalate, dimethyl isophthalate, diphenyl isophthalate, dimethyl terephthalate or dioctyl terephthalate. 3. The ester compound of claim 1, wherein the ester compound having at least one hydroxy group is 2-hydroxy ethylacrylate, 2-hydroxy ethylmethacrylate, 2-hydroxypropyl acrylate, 2-hydroxy propyl. Unsaturated fatty acid esters comprising at least one hydroxy group such as methacrylate, 4-hydroxy butyl acrylate and pentaerythritol triacrylate; 2-hydroxy ethyl acetate, methyl 3-hydroxy butyrate, ethyl 3-hydroxy butyrate, methyl 2-hydroxy isobutyrate, ethyl 2-hydroxy isobutyrate, methyl-3-hydroxy-2-methyl propionate , 2,2-dimethyl-3-hydroxy propionate, ethyl-6-hydroxy hexanoate, t-butyl-2-hydroxy isobutyrate, diethyl-3-hydroxy glutarate, ethyl lactate , Isopropyl lactate, butyl isobutyl lactate, isobutyl lactate, ethyl mandelate, dimethyl ethyl tartrate, ethyl tartrate, dibutyl tartrate, diethyl citrate, triethyl citrate, ethyl 2-hydroxy Aliphatic monoesters or polyesters comprising at least one hydroxy group such as caproate and diethyl bis- (hydroxy methyl) malonate; 2-hydroxy ethyl benzoate, 2-hydroxy ethyl salicylate, methyl 4- (hydroxy methyl) benzoate, methyl 4-hydroxy benzoate, ethyl 3-hydroxy benzoate, 4-methyl salicylate Such as ethyl salicylate, phenyl salicylate, propyl 4-hydroxy benzoate, phenyl 3-hydroxy naphtanoate, monoethylene glycol monobenzoate, diethylene glycol monobenzoate and triethylene glycol monobenzoate Aromatic esters containing at least one hydroxy group; Or alicyclic esters comprising at least one hydroxy group such as hydroxy butyl lactone. The silicone compound according to claim 1 or 2, wherein the silicon compound having an alkoxy group is selected from the group consisting of dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, ethyltrimethoxysilane and vinyltrimethoxysilane. , Methyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, phenyltriethoxysilane, ethyltriisopropoxysilane, Ethylene polymerization or copolymerization method, characterized in that vinyl tributoxysilane, ethyl silicate, butyl silicate or methyltriaryloxysilane. The ethylene polymerization or copolymerization method according to claim 1 or 2, wherein the titanium compound in step (iii) is a compound having the following general formula (III). Ti (OR) _a X _4-a [Where R is an alkyl group having 1 to 10 carbon atoms, X is a halogen atom and a is an integer of 0 to 4] 10. The method of claim 9, wherein the titanium compound is tetrachlorotitanium. The ethylene polymerization or copolymerization method according to claim 1 or 2, wherein the silicone compound in step (iii) is a compound having the following general formula (IV). R _n SiCl _4-n ................................... (IV) [Wherein R is hydrogen or an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a haloalkyl group, an aryl group, a halosilyl group having 1 to 8 carbon atoms, or a halosilylalkyl group, and n is an integer of 0 to 3]       The method of claim 11, wherein the silicon compound is tetrachlorosilicon; Trichlorosilanes such as methyltrichlorosilane, ethyltrichlorosilane and phenyltrichlorosilane; Dichlorosilanes such as dimethyldichlorosilane, diethyldichlorosilane, diphenyldichlorosilane and methylphenyldichlorosilane; Ethylene polymerization or copolymerization method characterized in that the monochlorosilane, such as trimethylchlorosilane or a mixture thereof. The process of claim 1 or 2, wherein the preactivating step (iv) comprises the following steps: (c) contacting the solid complex titanium catalyst with 0.02 mol to 1 mol of the poly (hydrobakyl-aluminum oxide) compound per mole of the magnesium compound at -50 to 50 ° C; And (d) then gradually raising the temperature to the range of 0 to 150 ℃, and then reacted for 0.5 to 5 hours. The ethylene polymerization or copolymerization method according to claim 1 or 2, wherein the organometallic compound of Group II or Group III of the periodic table has the following general formula (VI). MR _n ㆍ ‥‥‥ (VI) [Where M is a periodic table group II or IIIA metal component such as magnesium, calcium, zinc, boron, aluminum and gallium, and R is 1-20 carbon atoms such as methyl, ethyl, butyl, hexyl, octyl and decyl Alkyl groups, and n is the valence of the metal component.] The method of claim 1, wherein the haloalkane compound is ethyl chloride, chloroform, tertiary butyl chloride, tetrachloromethane, ethyl bromide, tertiary butyl iodide, normal butyl bromide, normal butyl iodide, normal Ethylene polymerization or copolymerization method characterized in that the butyl fluoride, or a mixture thereof.