KR20160121705A - Preparation method of metallocene catalyst and preparation method of ultra high molecular weight polyethylene by using thereof - Google Patents

Abstract

The present invention relates to a method of preparing ultra high molecular weight polyethylene using polymethyl aluminoxane, and ultra high molecular weight polyethylene prepared by the method. The method of preparing the ultra high molecular weight polyethylene includes: forming a slurry by mixing polymethyl aluminoxane composition particles, a metallocene, an antistatic agent and a hydrocarbon solvent having 4 to 14 carbon atoms (step 1); polymerizing the polyethylene by continuously feeding and stirring the slurry, alkyl aluminum, the hydrocarbon solvent having 4 to 14 carbon atoms and, an ethylene monomer (step 2); and and filtering and drying the obtained polyethylene (step 3). According to the present invention, the ultra high molecular weight polyethylene resin having a fine particle size larger than that of a commercially available product can be produced by preparing the ultra high molecular weight polyethylene using a non-supported metallocene catalyst.

Description

METHOD FOR PREPARING METALLOCENE CATALYST AND METHOD FOR PREPARING ULTRA HIGH MOLECULAR WEIGHT POLYETHYLEN THEREOF Technical Field [

More particularly, the present invention relates to a method for producing ultra high molecular weight polyethylene using solid polymethyl aluminoxane and metallocene catalyst and a method for producing ultra high molecular weight polyethylene .

Ultrahigh molecular weight polyethylene (UHMWPE) is a polyethylene having a molecular weight of at least 106 g / mol and has a very high molecular weight as compared with general polyethylene. Therefore, it has excellent mechanical strength, abrasion resistance, rigidity, slip property And the like. Particularly, since the abrasion resistance is superior to that of metal and is 2-3 times more than most engineering plastics, there is a feature that the maintenance cost is low when it is used in mechanical parts and conveyors requiring abrasion resistance such as gears, bearings, cams, The coefficient of friction of polyethylene is similar to that of fluorine resin, so it can be used without lubricant when used in conveyor and various parts.

Because ultrahigh molecular weight polyethylene has a high molecular weight, there is almost no flowability in the molten state. Therefore, it can not be molded by general processing methods such as injection, extrusion, and blowing. Therefore, after the primary processing with a compression sheet or a compression rod at high temperature and high pressure Milling, and lathe, so that the desired mechanical parts can be manufactured.

The ultrahigh molecular weight polyethylene resin suitable for compression sheet or compression rod processing is advantageous in that the particles have a uniform size (span value of 1.0 or less) and a small size (100 to 140 탆).

In addition, when it is manufactured into a fiber or film form, a wet processing method in which paraffin oil is melted and processed is used. When the ultra high molecular weight polyethylene is processed by this method, the particle size is small and the particle uniformity is excellent, So that the desired shape of the workpiece can be obtained.

However, since the supported metallocene catalyst used for producing polyethylene having excellent physical properties has a large silica carrier of 20 μm or more, a polyethylene polymer having a size of 400 μm or more is produced and the processability is weak. Therefore, A new process capable of producing ultra-high molecular weight polyethylene resin at a commercial product level of about 140 탆 is required.

Published Patent No. 10-2001-0097493 Published Patent No. 10-2010-0023278

It is an object of the present invention to provide a method for producing ultra high molecular weight polyethylene having excellent physical properties and processability using a metallocene catalyst.

An object of the present invention is to provide a catalyst having a high activity, a low facility investment cost and a simple production method, and a method for producing ultra high molecular weight polyethylene using the same.

In order to solve the above problems, the present invention provides a method for producing a slurry of solid polymethyl aluminoxane composition particles, a metallocene, an antistatic agent, and a hydrocarbon solvent having carbon atoms of 4 to 14 carbon atoms, Polymerizing the polyethylene by mixing and stirring the slurry, the alkyl aluminum, the hydrocarbon solvent having carbon atoms of 4 to 14 carbon atoms and the ethylene monomer prepared in step 1 above (step 2); And a step (3) of filtering and drying the obtained polyethylene, thereby producing a high molecular weight polyethylene.

The particles of the solid polymethylaluminoxane composition may be obtained by mixing a polymethylaluminoxane composition solution containing polymethylaluminoxane and trimethylaluminum with an aromatic hydrocarbon solvent and heating.

The heating may be carried out at 80 to 200 캜.

The aromatic hydrocarbon solvent may be at least one compound selected from the group consisting of benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, chlorobenzene, and dichlorobenzene.

The polymethylaluminoxane composition solution may have a molar fraction of the methyl group derived from trimethylaluminum relative to the total number of moles of the methyl group of 15 mol% or less.

The polymethylaluminoxane composition solution can be obtained by pyrolysis of an alkyl aluminum compound having an aluminum-oxygen-carbon bond.

The alkyl aluminum compound having an aluminum-oxygen-carbon bond can be prepared by reacting trimethyl aluminum with an organic compound containing oxygen.

The step 1 may be carried out by reacting the solid polymethylaluminoxane composition particles with an antistatic agent in the hydrocarbon solvent, and then adding metallocene.

The antistatic agent may be at least one compound selected from the group consisting of A, B and C.

The hydrocarbon solvent having a carbon atom of 4 to 14 carbon atoms may be at least one compound selected from the group consisting of pentane, hexane, cyclohexane, methylcyclohexane, heptane, octane, decane and isopentane.

The step 2 may be carried out in a polymerization reactor under a pressure condition of 3 to 15 bar, and is preferably carried out at 60 to 90 캜 for 3 hours or more.

The step 2 may include a step of preliminarily polymerizing the slurry and the ethylene monomer in a polymerization reactor to produce a single or copolymerized prepolymer. The prepolymerization may be performed at a temperature of 20 ° C to 50 ° C and a pressure of 0.1 to 2 bar Pressure conditions for 30 minutes to 2 hours.

At this time, the prepolymer preferably has a yield of 0.2 to 10 g-polymer / g-catalyst.

The antistatic agent may be at least one compound selected from the group consisting of A, B, and C. In the step 2, the antistatic agent may further comprise an antistatic agent.

The step 2 may further include hydrogen.

The polyethylene has a 3 x 10 ^ 5g / mol or more molecular weight, from 50 to an average particle size of 200㎛ (d50), 0.01 to span (span) of 1.0 measured by ASTM 4020 manufactured through the step 3 (log ₁₀ (d90 / d10)). < / RTI >

The present invention also provides a 3 x 10 ^ 5g / mol or more molecular weight, from 50 to 200㎛ average particle size (d50) of 0.01 to span (span) (log ₁₀ of 1.0 measured by the ASTM 4020 prepared by the above method ( d90 / d10)). The present invention also provides an ultra high molecular weight polyethylene.

The present invention can produce an ultrahigh molecular weight polyethylene resin having a fine particle size higher than that of a commercial product by preparing an ultrahigh molecular weight polyethylene using a non-supported metallocene catalyst.

Since the supported metallocene catalyst is not used in the present invention, it is possible to produce an ultrahigh molecular weight polyethylene resin of excellent purity without using an impurity inhibitor because the generation of impurities is small.

1 is a schematic diagram of an overall process according to an embodiment of the present invention.
2 is a schematic view of a process for producing a catalyst slurry according to an embodiment of the present invention.
Figure 3 is a schematic diagram of a polymerization process in accordance with one embodiment of the present invention.
4 is a graph showing the results of laser particle analysis of Example 3. Fig.
FIG. 5 is a photograph of ultra high molecular weight polyethylene prepared according to one embodiment of the present invention and ultra high molecular weight polyethylene prepared by a conventional method using solid polymethyl aluminoxane.
Figure 6 is a photograph of ultra high molecular weight polyethylene prepared according to one embodiment of the present invention
7 is a photograph of ultra high molecular weight polyethylene prepared by a conventional method using solid polymethylaluminoxane.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below, but may be embodied in various other forms.

The present embodiments are provided so that the disclosure of the present invention is thoroughly disclosed and that those skilled in the art will fully understand the scope of the present invention.

And the present invention is only defined by the scope of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings.

However, the present invention is not limited to the embodiments described below, but may be embodied in various other forms.

The present embodiments are provided so that the disclosure of the present invention is thoroughly disclosed and that those skilled in the art will fully understand the scope of the present invention.

And the present invention is only defined by the scope of the claims.

Thus, in some embodiments, well known components, well known operations, and well-known techniques are not specifically described to avoid an undesirable interpretation of the present invention.

In addition, throughout the specification, like reference numerals refer to like elements, and the terms (mentioned) used herein are intended to illustrate the embodiments and not to limit the invention.

In this specification, the singular forms include plural forms unless the context clearly dictates otherwise, and the constituents and acts referred to as " comprising (or comprising) " do not exclude the presence or addition of one or more other constituents and actions .

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs.

Also, commonly used predefined terms are not ideally or excessively interpreted unless they are defined.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1, the present invention relates to a solid polymethylaluminoxane composition particle, a metallocene, an antistatic agent, and a solid polymer having a carbon number of 4 to 14, in order to solve the problem of producing ultra high molecular weight polyethylene using a supported metallocene catalyst. Of a hydrocarbon solvent having a carbon atom to prepare a slurry (step 1); Polymerizing the polyethylene by mixing and stirring the slurry, the alkyl aluminum, the hydrocarbon solvent having carbon atoms of 4 to 14 carbon atoms, and the ethylene monomer prepared in step 1 above (step 2); (Step 3) of filtering and drying the obtained polyethylene, and the ultrahigh molecular weight polyethylene prepared by the above production method.

As the particles of the solid polyaluminoxane composition, solid polyaluminoxane particles obtained by mixing a solution of a polymethylaluminoxane composition containing polymethylaluminoxane and trimethylaluminum with an aromatic hydrocarbon solvent and heating at 80 to 200 ° C can be used .

At this time, it is preferable that the molar fraction of the methyl group derived from the trimethylaluminum is 15 mol% or less relative to the total number of moles of the methyl group in the polymethylaluminoxane composition solution, and as the molar fraction of the methyl group derived from the trimethyl aluminum segment increases, And it is more preferable that it is contained in an amount of 12 mol% or less because the particles tend to be easily broken.

The polymethylaluminoxane composition solution may be a solution obtained by pyrolysis of an alkyl aluminum compound having an Al-O-C bond at 30 DEG C to 80 DEG C for 5 to 100 hours.

The alkylaluminum compound having an Al-OC bond can be prepared by reacting trimethylaluminum with an organic compound containing oxygen. The molar ratio of the aluminum atom contained in the trimethylaluminum and the oxygen of the organic compound containing oxygen Atoms in a molar ratio of 1: 0.5 to 3.

The organic compound containing oxygen may be, for example, a carboxylic acid compound having a carboxy group or a carboxylic acid anhydride, and specifically includes formic acid, acetic acid, propionic acid, n-butyric acid, n- valeric acid, , stearic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, benzoic acid, phthalic acid, citric acid, tartaric acid, lactic acid, malic acid, toluenic acid, toluenic anhydride, But are not limited to, compounds selected from the group consisting of acetic anhydride, acetic anhydride, acetic anhydride, acetic anhydride,

The aromatic hydrocarbon solvent may be at least one material selected from the group consisting of benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, chlorobenzene, and dichlorobenzene, but is not limited thereto.

Since the solid polymethylaluminoxane composition particles are used in the present invention, there is no need to support the metallocene on the carrier, so that the production of impurities is minimized, so that it is possible to produce high purity ultra-high molecular weight polyethylene. In addition, The stabilizer addition procedure is not necessary, and the production is simple, the manufacturing cost can be reduced, and the ultra high molecular weight polyethylene can be synthesized rapidly.

As shown in FIG. 2, Step 1, which is a catalyst preparation step, can be carried out in two steps of stirring the solid polymethylaluminoxane composition particles and antistatic agent in a hydrocarbon solvent, reacting them, and then adding metallocene.

The hydrocarbon solvent may be used for a hydrocarbon having a carbon atom of 4 to 14 carbon atoms, for example, at least one compound selected from the group consisting of pentane, hexane, cyclohexane, methylcyclohexane, heptane, octane, decane and isopentane But is not limited thereto.

When the antistatic agent is used in the catalyst preparation step as described above, it is possible to improve the aggregation phenomenon due to the localized catalyst agglomeration or the excessive chain growth, and it is more effective to increase the molecular weight and to improve the aggregation phenomenon than to use the antistatic agent in the polymerization step great.

In addition, since the preparation of the catalyst is divided into two stages while using the antistatic agent, the reduced polymerization activity due to the use of the antistatic agent can be improved, and a more excellent agglomeration phenomenon can be exhibited than the case where only the antistatic agent is used.

As the antistatic agent, at least one compound selected from the group consisting of glyceryl stearate, glyceryl monostearate, alkyl amine, ethoxylated alkyl amine, alkyl sulfonate and glyceryl ester may be used, It is not.

In addition, a registered trademark Armostat, Octastat, Statsafe or Atmer, which is a commercially available antistatic agent, may be used, and in particular, it is best to use octastat 2000 desirable.

The antistatic agent is preferably contained in an amount of 10 parts by weight to 50 parts by weight based on 100 parts by weight of the solid polymethylaluminoxane composition particles. If the antistatic agent is contained in an amount of less than 10 parts by weight, it can not inhibit local catalyst aggregation or excessive chain growth, And if it is contained in an amount exceeding 50 parts by weight, the activity of the solid polymethylaluminoxane composition and the metallocene catalyst is reduced to generate a low molecular weight polymer and inhibit the insertion of olefins.

The metallocene may be added so that the molar ratio of the transition metal in the metallocene to the aluminum in the solid polymethylaluminoxane composition particles is 150: 1 to 600: 1.

If the metallocene catalyst is excessively added to the molar ratio, there is a problem that the amount of increase in activity relative to the amount of metallocene used is small and a low molecular weight polymer is generated. On the other hand, when the solid polymethyl aluminoxane composition particles are excessively added, There is a problem of reducing morphology.

The metallocene compound used in the present invention is a metallocene compound having a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a substituted indenyl group, or a substituted indenyl group in which a transition metal of Group 4 of the periodic table (for example, titanium, zirconium, , A fluorenyl group, and a substituted fluorenyl group. Examples of metallocene catalysts include bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium methyl chloride, bis (cyclopentadienyl) zirconium dimethyl, bis (methylcyclopentadienyl) zirconium dichloride (Ethylcyclopentadienyl) zirconium dichloride, bis (ethylcyclopentadienyl) zirconium methylchloride, bis (methylcyclopentadienyl) zirconium dichloride, bis Bis (pentamethylcyclopentadienyl) zirconium dimethyl chloride, bis (pentamethylcyclopentadienyl) zirconium dimethyl, bis (pentamethylcyclopentadienyl) zirconium dichloride, bis -Cyclopentadienyl) zirconium dichloride, bis (n-butyl-cyclopentadienyl) zirconium methylchloride Zirconium dichloride, bis (indenyl) zirconium methyl chloride, bis (indenyl) zirconium dimethyl, bis (2-methyl-indenyl) zirconium dichloride, bis ) Zirconium dichloride, bis (2-methyl-indenyl) zirconium dichloride, bis (2-phenyl- indenyl) zirconium dichloride, bis (Cyclopentadienyl) zirconium dichloride, dimethylsilylbis (cyclopentadienyl) zirconium methylchloride, dimethylsilylbis (cyclopentadienyl) zirconium dichloride, (Indenyl) zirconium dimethyl, dimethylsilylbis (indenyl) zirconium dichloride, dimethylsilyl (indenyl) zirconium methyl chloride, dimethylsilyl (indenyl) zirconium dimethyl, dimethyl Zirconium dichloride, dimethylsilylbis (2-methyl-indenyl) zirconium methylchloride, dimethylsilylbis (2-methyl-indenyl) zirconium dimethyl, dimethylsilylbis Zirconium dichloride, dimethylsilyl (indenyl cyclopentadienyl) zirconium dichloride, dimethylsilyl (indenylcyclopentadienyl) zirconium dimethyl, dimethylsilyl (fluorenylcyclopentadienyl) zirconium dichloride (Cyclopentadienyl) zirconium dichloride, ethylene bis (cyclopentadienyl) zirconium dichloride, dimethylsilyl (fluorenylcyclopentadienyl) zirconium dichloride, Zirconium dichloride, zirconium methyl chloride, ethylene bis (cyclopentadienyl) zirconium dimethyl, ethylene bis (indenyl) zirconium dichloride, (2-methyl-indenyl) zirconium dichloride, ethylene bis (indenyl) zirconium methyl chloride, ethylene bis (indenyl) zirconium dimethyl, ethylene bis (Indenyl cyclopentadienyl) zirconium dichloride, ethylene (indenyl cyclopentadienyl) zirconium methyl chloride, ethylene (indenyl cyclopentadienyl) zirconium dimethyl, ethylene (Cyclopentadienyl) zirconium dichloride, ethylene (fluorenylcyclopentadienyl) zirconium dichloride, ethylene (fluorenylcyclopentadienyl) zirconium dichloride, ethylene (fluorenylcyclopentadienyl) (Cyclopentadienyl) zirconium methyl chloride, isopropylbis (cyclopentadienyl) zirconium (Indenyl) zirconium dichloride, isopropyl bis (indenyl) zirconium dichloride, isopropyl bis (indenyl) zirconium dichloride, isopropyl bis (Indenyl cyclopentadienyl) zirconium dichloride, isopropyl (indenyl cyclopentadienyl) zirconium dichloride, isopropyl (2-methyl-indenyl) zirconium dichloride, Isopropyl (fluorenylcyclopentadienyl) zirconium dichloride, isopropyl (fluorenylcyclopentadienyl) zirconium methyl chloride and iso (cyclopentadienyl) zirconium dichloride, Propyl (cyclopentadienyl) zirconium dimethyl and the like.

Referring to FIG. 3, step 2 includes polymerizing polyethylene by continuously feeding the slurry, an alkylaluminum cocatalyst, a hydrocarbon solvent having carbon atoms of 4 to 14 carbon atoms, and an ethylene monomer and stirring.

It is preferable that 300 to 2000 parts by weight of alkyl aluminum is contained in 100 parts by weight of the slurry. If the amount of the alkyl aluminum is less than 300 parts by weight, the bulk density of the polymer is lowered. If the amount of the alkyl aluminum is more than 2000 parts by weight, the inorganic content of the polymer may increase.

Alkylaluminum is selected from the group consisting of trimethylaluminum, triethylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum chloride, ethylaluminum dichloride and ethylaluminum sesquichloride The above materials may be used, but are not limited thereto.

The hydrocarbon solvent may be used for a hydrocarbon having a carbon atom of 4 to 14 carbon atoms, for example, at least one compound selected from the group consisting of pentane, hexane, cyclohexane, methylcyclohexane, heptane, octane, decane and isopentane But is not limited thereto.

The ultra high molecular weight polyethylene polymerization can be carried out at 60 ° C to 90 ° C, 3 to 15 bar for 2 to 4 hours.

The prepolymerization can be carried out for a short time at a mild temperature and low pressure condition before carrying out the polymerization step, preferably at 20 ° C to 50 ° C, at 0.1 to 2 bar for 30 minutes to 2 hours.

When prepolymerization is carried out under the above conditions, a prepolymer of 0.2 to 10 g-polymer / g-catalyst can be produced. By performing the prepolymerization under the above conditions, polymerization heat control of the ultrahigh molecular weight polyethylene So that the aggregation phenomenon can be alleviated.

After prepolymerization under the above conditions, polyethylene can be prepared through the main polymerization to produce a macromolecular ultra-high molecular weight polyethylene with a high yield of 20000 g-polymer / g-catalyst.

The antistatic agent may further include an antistatic agent in the preliminary polymerization or the main polymerization step. Examples of the antistatic agent include glyceryl stearate, glyceryl monostearate, alkylamine, ethoxylated alkylamine, alkylsulfonate, But are not limited to, one or more compounds selected from the group consisting of alkyl esters,

In addition, a registered trademark Armostat, Octastat, Statsafe or Atmer, which is a commercially available antistatic agent, may be used, and in particular, it is best to use octastat 2000 desirable.

The antistatic agent is preferably contained in an amount of 20 to 80 parts by weight based on 100 parts by weight of the slurry. If the antistatic agent is contained in an amount of less than 20 parts by weight, it may fail to inhibit localized catalyst aggregation or excessive chain growth to cause fouling or aggregation , If it exceeds 80 parts by weight, the activity of the solid polymethylaluminoxane composition and the metallocene catalyst is reduced to generate a low molecular weight polymer and inhibit the insertion of olefin.

The present polymerization may also be carried out by further including hydrogen to adjust the molecular weight of the polyethylene to be produced.

The ultrafast molecular weight polyethylene can be prepared through the step of filtering and drying the finally obtained polyethylene.

The ultra high molecular weight polyethylene prepared by the step 3 is measured by the ASTM 4020 3 x 10 ^ 5g / mol or more molecular weight, from 50 to an average particle size of 200㎛ (d50), 0.01 to span (span) (log ₁₀ 1.0 (d90 / d10)).

Hereinafter, preferred embodiments and test examples of the present invention will be described in detail. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments, test examples, and drawings described in this specification are preferred embodiments of the present invention and do not represent all the technical ideas of the present invention, so that there are various equivalents and modifications that can be substituted at the time of the present application .

1. Comparative Example

(Slurry catalyst preparation)

(Indenyl) zirconium dichloride (Ind ₂ ZrCl ₂ ) was added so as to have an Al / Zr ratio of 300 by adding a magnet bar, 250 ml of hexane and 1 g of solid polymethylaluminoxane to a 500 ml glass bottle in which moisture was completely removed Followed by stirring at 30 占 폚 for 30 minutes.

(Ethylene polymerization)

A 2L stainless steel autoclave equipped with a magnetic stirrer was thoroughly purged with nitrogen, 900 ml of hexane, 200 mg of triethylaluminum and 16 mg of a slurry catalyst were added successively.

Ethylene was continuously added to an autoclave at -600 mmHg and 65 deg. C, and the polymerization was carried out for 2 hours under the conditions of 11 kg / cm2G and 70 deg.

After the completion of the polymerization, the temperature of the reactor was lowered to room temperature, the unreacted gas was removed, and the polyethylene was filtered and dried to obtain 223 g of ultrahigh molecular weight polyethylene as a white powder.

Except for the powder around the impeller, the reactor condition was good. The obtained ultrahigh molecular weight polyethylene had a viscosity average molecular weight of 5.6 × 10 5, an average particle size of 111.7 μm, a Span value of 0.67 and a bulk density of 0.43 As shown in FIG. 7, the produced polyethylene had a clustered phenomenon.

3. Example 1

(Slurry catalyst preparation)

A slurry catalyst was prepared in the same manner as in Comparative Example.

(Ethylene polymerization)

Example 1 was polymerized in the same manner as in Comparative Example except that 10 mg of Octastat 2000 was added to obtain 147 g of ultrahigh molecular weight polyethylene. The obtained ultrahigh molecular weight polyethylene had a viscosity average molecular weight of 4.9 × 10 5, an average particle size of 97.2 μm, a span value of 0.72, and a bulk density of 0.40.

4. Example 2

(Slurry catalyst preparation)

250 ml of a magnet bar and hexane were placed in a 500 ml glass bottle in which water was completely removed and 0.2 g of bis (indenyl) zirconium dichloride (Ind ₂ ZrCl ₂ ) and octastat 2000 were added thereto so that the Al / Zr ratio became 300, C for 30 minutes, 1 g of solid polymethylaluminoxane was added to the obtained product, and the mixture was stirred at 30 캜 for 30 minutes.

(Ethylene polymerization)

100 g of ultrahigh molecular weight polyethylene was obtained by polymerization in the same manner as in Comparative Example. The obtained ultrahigh molecular weight polyethylene had a viscosity average molecular weight of 5.4 × 10 5, an average particle size of 85.5 μm, a span value of 0.68, and a bulk density of 0.34.

2. Example 3

(Slurry catalyst preparation)

After adding a magnet bar, 250 ml of hexane, 1 g of solid polymethylaluminoxane and 0.2 g of Octastat 2000 to a 500 ml glass bottle in which the water was completely removed, and stirring the mixture at 30 ° C for 30 minutes, the obtained Al / Zr ratio was 300 (Indenyl) zirconium dichloride (Ind ₂ ZrCl ₂ ) was added thereto, and the mixture was stirred at 30 ° C for 30 minutes.

(Ethylene polymerization)

Polymerization was carried out in the same manner as in the Comparative Example to obtain 295 g of ultrahigh molecular weight polyethylene. The viscosity - average molecular weight of the obtained ultrahigh molecular weight polyethylene increased to 9.8 × 10 5, and the average particle size was 122.6 μm, the span value was 0.68, and the bulk density was 0.45.

5. Example 4

(Slurry catalyst preparation)

A slurry catalyst was prepared in the same manner as in Example 3.

(Prepolymerization)

100 ml of hexane, 0.25 g of triethylaluminum and 0.5 g of the catalyst slurry obtained in the same manner as in Example 3 were sequentially added to a 355 ml glass reactor (Andrews Glass Co. 12 oz.) And stirred at 30 DEG C and 0.5 bar at a stirring speed of 150 rpm for 1 hour Lt; / RTI >

(Ethylene polymerization)

310 g of ultrahigh molecular weight polyethylene was obtained by polymerization in the same manner as in Comparative Example. The obtained ultrahigh molecular weight polyethylene had a viscosity average molecular weight of 8.8 X 10 < -5 >, increased molecular weight, an average particle size of 124.7 mu m, a Span value of 0.68, and a bulk density of 0.45. There was no aggregation as shown.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. In addition, it is a matter of course that various modifications and variations are possible without departing from the scope of the technical idea of the present invention by anyone having ordinary skill in the art.

Claims (11)

Mixing a solid polymethylaluminoxane composition particle, a metallocene, an antistatic agent, and a hydrocarbon solvent having a carbon atom of 4 to 14 carbon atoms to prepare a slurry (step 1);
Polymerizing the polyethylene by mixing and stirring the slurry, the alkyl aluminum, the hydrocarbon solvent having carbon atoms of 4 to 14 carbon atoms, and the ethylene monomer prepared in step 1 above (step 2);
And filtering and drying the resultant polyethylene (step 3).
The method according to claim 1,
Wherein the particles of the solid polymethylaluminoxane composition are obtained by mixing a polymethylaluminoxane composition solution containing polymethylaluminoxane and trimethylaluminum with an aromatic hydrocarbon solvent and heating the resultant mixture.
The method of claim 2,
Wherein the heating is carried out at a temperature of 80 ° C to 200 ° C.
The method of claim 2,
Wherein the aromatic hydrocarbon solvent is at least one compound selected from the group consisting of benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, chlorobenzene and dichlorobenzene.
The method according to claim 1,
Wherein the step (1) comprises reacting the particles of the solid polymethylaluminoxane composition with the antistatic agent in the hydrocarbon solvent to react with the metallocene, and then adding metallocene.
The method of claim 5,
Wherein the antistatic agent is at least one compound selected from the group consisting of glyceryl stearate, glyceryl monostearate, alkylamine, ethoxylated alkylamine, alkylsulfonate and glyceryl ester. ≪ / RTI >
The method according to claim 1,
The hydrocarbon solvent having a carbon number of 4 to 14 carbon atoms is at least one compound selected from the group consisting of pentane, hexane, cyclohexane, methylcyclohexane, heptane, octane, decane and isopentane. Gt;
The method according to claim 1,
Wherein the step 2 is carried out in a polymerization reactor under a pressure condition of 3 to 15 bar.
The method of claim 5,
Step 2 comprises preliminarily polymerizing the slurry and the ethylene monomer at 20 DEG C to 50 DEG C in a polymerization reactor of 0.1 to 2 bar for 30 minutes to 2 hours to produce a single or copolymerized prepolymer, Lt; RTI ID = 0.0 > g-polymer / g-catalyst. ≪ / RTI >
The method according to claim 1,
The polyethylene has a 3 x 10 ^ 5g / mol or more molecular weight, from 50 to an average particle size of 200㎛ (d50), 0.01 to span (span) of 1.0 measured by ASTM 4020 manufactured through the step 3 (log ₁₀ (d90 / d10)). < / RTI >
Of claims 1 to 13, the method 3 x 10 measured by ASTM 4020 is manufactured with the ^ 5g / mol or more with a molecular weight average particle size of 50 to 200㎛ (d50), 0.01 to 1.0, the span (span) (log ₁₀ (d90 / d10)). < / RTI >

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