KR101719042B1 - Method for preparing polyolefin and polyolefin prepared thereby - Google Patents

Abstract

(상기 화학식 1에서, A, R¹~R⁴, R^3' R^4', M, X 및 n는 명세서 중에서 정의한 바와 같다)The present invention relates to a process for preparing a mixture comprising mixing a polar monomer containing a straight chain hydrocarbon group having 8 or more carbon atoms in a molecule and a polar functional group with an organoaluminum compound at a molar ratio of 1: 1.5 to 1: 3 to prepare a mixture; And polymerizing the polymeric polar functional group at a temperature of 40 to 80 DEG C in the presence of an olefin polymerization catalyst comprising a metallocene compound represented by the following formula 1 after mixing the ethylene monomer with the above- Mol% or more, and a polyolefin prepared using the same.
[Chemical Formula 1]

(Wherein A, R ¹ to R ⁴ , R ^{3 '} R ^4' , M, X and n are as defined in the specification)

Description

METHOD FOR PREPARING POLYOLEFIN AND POLYOLEFIN PREPARED THEREBY BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin,

The present invention relates to a process for preparing a functional polyolefin using a metallocene catalyst and a polyolefin produced by the process.

BACKGROUND ART Polyolefins are widely used for extrusion molded articles, blow molded articles and injection molded articles because of their excellent moldability, heat resistance, mechanical properties, hygienic quality, water vapor permeability and appearance characteristics of molded articles. However, polyolefins, particularly polyethylene, have a problem of low compatibility with polar resins such as nylon because of the absence of polar groups in the molecule, and low adhesiveness to polar resins and metals. As a result, it has been difficult to blend the polyolefin with a polar resin or a metal, or to laminate it with these materials. Further, a molded article of polyolefin has a problem of low surface hydrophilicity and antistatic property.

In order to solve such a problem and to increase the affinity for a polar material, a method of grafting a polar group-containing monomer onto a polyolefin through radical polymerization has been widely used. However, this method has a problem in that cross-linking of the polyolefin and molecular chain breakage occur during the grafting reaction, and the viscosity balance of the graft polymer and the polar resin is poor and the miscibility is low. There is also a problem in that the appearance characteristics of a molded article are low due to a gel component produced by intramolecular crosslinking or a foreign substance generated by cleavage of molecular chains.

In addition, a method of producing an olefin polymer such as an ethylene homopolymer, an ethylene / alpha -olefin copolymer, a propylene homopolymer or a propylene / alpha -olefin copolymer can be carried out by copolymerizing a polar monomer with a metal catalyst such as a titanium catalyst or a vanadium catalyst Was used. However, when a polar monomer is copolymerized using the metal catalyst as described above, there is a problem that the molecular weight distribution or the composition distribution is wide and the polymerization activity is low.

As another method, there is known a method of polymerizing in the presence of a transition metal compound such as zirconocene and a metallocene catalyst comprising an organic aluminum oxy compound (aluminoxane). When a metallocene catalyst is used, a high molecular weight olefin polymer is obtained with high activity, and the resulting olefin polymer has a narrow molecular weight distribution and a narrow composition distribution.

Alternatively, a metallocene compound having a ligand of a non-crosslinked cyclopentadienyl group, a crosslinked or non-crosslinked bisindenyl group, or an ethylene crosslinked unsubstituted indenyl / fluorenyl group is used as a catalyst to prepare a polyolefin containing a polar group As a method, a method using a metallocene catalyst is also known. However, these methods have a disadvantage in that the polymerization activity is very low. For this reason, although a method of protecting a polar group by a protecting group has been carried out, there is a problem that the process becomes complicated because the protecting group must be removed again after the reaction when a protecting group is introduced.

The ansa-metallocene compound is an organometallic compound containing two ligands connected to each other by a bridge group, in which the rotation of the ligand is prevented by the bridge group, The structure is determined.

These anisometallocene compounds are used as catalysts in the production of olefinic homopolymers or copolymers. In particular, it is known that an anisometallocene compound containing a cyclopentadienyl-fluorenyl ligand can produce a high molecular weight polyethylene, thereby controlling the microstructure of the polypropylene have.

It is also known that an anhydride-metallocene compound containing an indenyl ligand can produce a polyolefin having excellent activity and improved stereoregularity.

As described above, various researches have been made on anthra-metallocene compounds capable of controlling the microstructure of olefin-based polymers while having higher activity, but the degree of such anisotropy is still insufficient.

Korean Registered Patent No. 288272 (registered on May 2, 2001)

A first object of the present invention is to provide a method for producing a polyolefin having a high polar functional group incorporated therein by using a highly active metallocene catalyst containing bisindene as a ligand .

A second technical object of the present invention is to provide a polyolefin produced by the above process.

According to one embodiment of the present invention, a polar monomer having at least 8 carbon atoms in a linear hydrocarbon group and a polar functional group in a molecule is mixed with an organoaluminum compound in a molar ratio of 1: 1.5 to 1: 3 Preparing a mixture; And polymerizing the polar functional group in the polymer at a temperature of 40 to 80 DEG C in the presence of an olefin polymerization catalyst comprising a metallocene compound represented by the following formula 3 mol% or more of the polyolefin.

[Chemical Formula 1]

(In the formula 1,

M is selected from the group consisting of a Group 3 transition metal, a Group 4 transition metal, a Group 5 transition metal, a lanthanide series transition metal, and an ethanide series transition metal;

A is an element of Group 14;

R ¹ is selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, and an aryl group having 6 to 30 carbon atoms;

R ² is selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms and an aryl group having 6 to 30 carbon atoms ;

R ³ , R ^{3 '} , R ⁴ and R ^4' each independently represents an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, An aryl group having 6 to 30 carbon atoms;

Each X is independently a halogen group;

and n is an integer of 1 to 20)

According to another embodiment of the present invention, there is provided a polyolefin produced by the above-mentioned production method and containing at least 3 mol% of a polar functional group.

By the process for producing a polyolefin according to the present invention, a polyolefin introduced with a high content of polar functional groups in the polymer can be easily produced with excellent efficiency. As a result, the process is particularly useful for the commercial production of polar functionalized polyolefins.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

A method for producing a polyolefin containing at least 3 mol% of a polar functional group in a polymer according to an embodiment of the present invention comprises reacting a polar monomer containing a linear functional group having a carbon number of 8 or more in a molecule and a polar functional group with an organoaluminum compound in a ratio of 1: To 1: 3 to prepare a mixture (step 1); And a step (step 2) of mixing the ethylene monomer with the mixture and then conducting a polymerization reaction at a temperature of 40 to 80 ° C in the presence of a catalyst for olefin polymerization comprising a metallocene compound represented by the following formula (1):

[Chemical Formula 1]

In Formula 1,

M is selected from the group consisting of a Group 3 transition metal, a Group 4 transition metal, a Group 5 transition metal, a lanthanide series transition metal, and an ethanide series transition metal;

A is a bridge group connecting an indenyl group, specifically a Group 14 element;

R ¹ is selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, and an aryl group having 6 to 30 carbon atoms;

R ² is selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms and an aryl group having 6 to 30 carbon atoms ;

R ³ , R ³ ', R ⁴ and R ⁴ ' each independently represents an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, An aryl group having 6 to 30 carbon atoms;

Each X is independently halogen;

n is an integer of 1 to 20;

More specifically, in Formula 1, R ¹ and R ² are each independently an alkyl group having 1 to 4 carbon atoms; R ³ and R ³ 'are each independently selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, and an arylalkyl group having 7 to 30 carbon atoms; R ⁴ and R ⁴ 'are each independently selected from the group consisting of an aryl group having 6 to 18 carbon atoms and an alkylaryl group having 7 to 20 carbon atoms; n is an integer from 1 to 6; A may be silicon (Si).

Step 1 for the production of a polyolefin containing 3 mol% or more of a polymeric polar functional group according to the present invention is a step 1 in which a polar monomer having a straight chain hydrocarbon group having a carbon number of 8 or more in a molecule and a polar functional group Is mixed with an organoaluminum compound.

The polar monomer is a comonomer of an ethylene monomer for producing a polyolefin, and includes a straight chain hydrocarbon group having 8 or more carbon atoms together with an intramolecular functional group.

In the case of a metallocene catalyst in general, the activity of the catalyst is greatly reduced as the amount of the monomer having a polar functional group is increased. In contrast, in the present invention, the distance between the polar functional group and the ethylenically unsaturated functional group is increased by including a long chain hydrocarbon group, thereby improving the activity of the metallocene catalyst, particularly the supported catalyst.

In the polar monomer, the polar functional group may be a carboxyl group, a carboxylic acid ester group, an alcoholic hydroxyl group, a phenolic hydroxyl group, an acid anhydride group, an amino group, an amide group, an epoxy group or a mercapto group, Ester group.

Specifically, the polar monomer may be a compound represented by the following formula (2).

(2)

In Formula 2,

R ⁵ is a linear alkanediyl group having 8 to 20 carbon atoms,

Y is a carboxyl group (-COOH) or a carboxylic acid ester group (-COOR, R is a lower alkyl group having 1 to 4 carbon atoms), and

p is an integer of 1 to 3, and when p is 2 or 3, each Y is the same or different.

In Formula 2, R ⁵ is selected from the group consisting of undecamethylene, dodecamethylene, tetradecamethylene, pentadecamethylene, hexadecamethylene, heptadecamethylene, octadecamethylene, nonadecamethylene and eicosamethylene Y is a carboxyl group, and p can be an integer of 1.

More specifically, the polar monomers are selected from the group consisting of 9-decenoic acid, 10-undecenoic acid, 11-dodecenoic acid, methyl 9-decenoate, methyl 10- undecenoate, Hexanoate, ethyl 6-heptenoate, ethyl 7-octenoate, ethyl 8-nonenoate, ethyl 9-decenoate, ethyl 10-undecenoate, ethyl 11-dodecenoate, isopropyl 9- Octenoate, isopropyl 10-undecenoate, isopropyl 11-dodecenoate, butyl 5-hexenoate, butyl 6-heptenoate, butyl 7-octenoate, butyl 8-nonenoate, butyl 9 -Decenoate, butyl 10-undecenoate, or butyl 11-dodecenoate, and the like, alone or in a mixture of two or more. More specifically, the polar monomer may be 10-undecenoic acid.

The polar monomer may be used in consideration of the content of the polar group or the content of the repeating unit derived from the polar monomer in the olefin polymer to be finally produced. Specifically, the polar monomer may be used at a concentration of 0.05 to 0.6 mol (M), more specifically, at a concentration of 0.08 to 0.48M.

On the other hand, the organoaluminum compound may be specifically a compound of the following formula (3).

(3)

(R _{a) m} AlZ _{3 -m}

In Formula 3,

R _a is selected from the group consisting of a hydrocarbon group of 1 to 12 carbon atoms, specifically an alkyl group of 1 to 12 carbon atoms, a cycloalkyl group of 3 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms,

Z is a halogen atom or a hydrogen atom, and

and m may be an integer of 1 to 3.

In Formula 3, R _a is more specifically a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an isobutyl group, a pentyl group, a hexyl group, an octyl group, a cyclopentyl group, a cyclohexyl group, Tolyl group, and m may be an integer of 3.

More specifically, examples of the organoaluminum compound include trialkylaluminum such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum and tri-2-ethylhexylaluminum; Alkenyl aluminum such as isoprenyl aluminum; Dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, diisopropylaluminum chloride, diisobutylaluminum chloride and dimethylaluminum bromide; Alkylaluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, isopropyl aluminum sesquichloride, butyl aluminum sesquichloride, and ethyl aluminum sesquibromide; Alkylaluminum dihalides such as methylaluminum dichloride, ethylaluminum dichloride, isopropylaluminum dichloride and ethylaluminum dibromide; Alkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride, and any one or a mixture of two or more thereof may be used. More specifically, the organoaluminum compound may be triisobutylaluminum.

The organoaluminum compound is mixed with the above-mentioned polar monomer and serves to increase the reactivity of the polar monomer during the subsequent polymerization reaction. Accordingly, it is preferable to optimize the mixing ratio of the polar monomer and the organoaluminum compound in the polymerization reaction. In particular, for the production of polyolefins comprising a polymeric polar functional group in an amount of 3 mol% or more, more specifically 3 to 11 mol%, the polar monomer and the organoaluminum compound are used in a molar ratio of 1: 1.5 to 1: 3, May be mixed at a molar ratio of 1: 1.5 to 1: 2. If the molar ratio of the organoaluminum compound to the polar monomer is out of the above range, it is difficult to prepare a polyolefin containing a polar group.

The organoaluminum compound may be used at a concentration of 0.1 to 1 M under conditions that satisfy the mixing ratio condition with the above-mentioned polar monomer.

In addition, the polar monomer and the organoaluminum compound may be mixed according to a conventional method. Specifically, the polar monomer may be mixed with an organoaluminum compound in an organic solvent.

The organic solvent may be a hydrocarbon-based organic solvent having 3 to 20 carbon atoms, and examples thereof include aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene; Aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane and octadecane; Alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane and methylcyclopentane; Petroleum oils such as gasoline, kerosene and light oil, and halides (chlorides, bromides, etc.) of the above aromatic hydrocarbons, aliphatic hydrocarbons and alicyclic hydrocarbons. Any one or a mixture of two or more thereof may be used. In addition, ethers such as ethyl ether and tetrahydrofuran may be used. The organic solvent may also be used as a solvent in the polymerization reaction.

In addition, the mixing may be carried out according to a conventional mixing method, specifically, a heat resistant / pressure-resistant apparatus such as an autoclave. More specifically, the mixing can be performed at a temperature of 20 to 100 DEG C and a pressure of 1 to 40 atm for 10 minutes.

Next, step 2 for the production of a polyolefin containing at least 3 mol% of an intramolecular polar functional group is a step of polymerizing the mixture prepared in step 1 with an ethylene monomer.

The polymerization reaction may be carried out by slurry polymerization, gas phase polymerization or liquid phase polymerization. For example, a liquid phase polymerization may be used when the catalyst is not supported on a solid carrier and used in a solution state.

Specifically, the polymerization reaction may be carried out in the presence of an olefin polymerization catalyst comprising the metallocene compound of Formula 1 after mixing the mixture prepared in Step 1 with an ethylene monomer.

In the catalyst for olefin polymerization, the metallocene compound of formula (1) includes two indenyl groups as ligands, and in particular, an oxygen-ligand group is added to a bridge group connecting the ligands. donor is substituted with a functional group capable of acting as a Lewis base, the activity as a catalyst can be maximized.

More specifically, the metallocene compound may be a compound represented by the following formula (1a).

[Formula 1a]

(Ph in the above formula (1a) is a phenyl group)

The metallocene compound may be used at a concentration of 0.01 to 0.05 mM during the polymerization.

The catalyst for olefin polymerization may be a catalyst supported on a support.

The carrier can be used without any particular limitation as long as it is used as a carrier in a metallocene catalyst. Specifically, the carrier may be silica, silica-alumina or silica-magnesia, and any one or a mixture of two or more thereof may be used.

In the case where the support is silica, there are few catalysts liberated from the surface during the olefin polymerization process because the functional groups of the silica carrier and the metallocene compound of Chemical Formula 1 form a chemical bond. As a result, it is possible to prevent fouling of the wall surface of the reactor or the polymer particles entangled with each other during the production process of the polyolefin. In addition, the polyolefin produced in the presence of the catalyst containing the silica carrier has excellent particle shape and apparent density of the polymer.

More specifically, the carrier may be a high-temperature dried silica or silica-alumina containing a siloxane group having high reactivity on its surface through a method such as high temperature drying.

The carrier may further comprise an oxide, carbonate, sulphate or nitrate component such as Na ₂ O, K ₂ CO ₃ , BaSO ₄ , or Mg (NO ₃ ) ₂ and the like.

In addition, the metallocene compound of the above formula (1) may be used as a catalyst for olefin polymerization itself, or may be used together with a cocatalyst as a catalyst precursor.

The cocatalyst may be alkylaluminoxane such as methylalumineoxane (hereinafter referred to as "MAO").

When such a cocatalyst is used, it can be used as a catalyst in which a halogen group (X) bonded to a metal element (M) of the metallocene compound is substituted with an alkyl group, for example, an alkyl group having 1 to 20 carbon atoms.

The cocatalyst may be used in an amount such that the molar ratio (Al / M) of metal (Al) in the cocatalyst to the metal (M) in the metallocene compound is 1000 to 5000, more specifically 2000 to 3000.

The above-mentioned ethylene monomer is a compound containing an intramolecular polymerizable unsaturated ethylene group and can be used without particular limitation as long as it is used in the production of a polyolefin.

The ethylene monomer may be used in various states, solid, liquid, or gas phase depending on the polymerization method. Specifically, in the present invention, gaseous ethylene monomers may be used, in which case the gaseous ethylene monomer may be fed to the mixture comprising the mixture prepared in step 1 and a catalyst, and optionally a cocatalyst.

Further, in the step 2, the polymerization reaction may be carried out at a temperature of 40 to 80 캜, more specifically 50 to 70 캜. If the temperature is lower than 40 ° C during the polymerization reaction, the polymer is not synthesized, and if it exceeds 80 ° C, there is a fear of fouling.

Further, the polymerization reaction may be carried out for 10 minutes to 1 hour, more specifically 10 minutes to 30 minutes.

In addition, the molecular weight range of the finally produced polymer product can be controlled according to the hydrogenation or non-addition conditions during the polymerization reaction. Particularly, a polyolefin having a high molecular weight can be produced under hydrogen-free conditions, and a low molecular weight polyolefin can be produced with a small amount of hydrogen under the condition of hydrogenation. At this time, the hydrogen content added to the polymerization reaction may be in the range of 0.07 L to 4 L under 1 atm of the reactor condition, or at a pressure of 1 bar to 40 bar in the reactor, or in a molar amount of hydrogen of 168 ppm to 8,000 ppm.

As described above, the method of producing a polyolefin according to an embodiment of the present invention uses a metallocene catalyst having high activity by including bisindene as a ligand, Can be easily produced.

According to another embodiment of the present invention, there is provided a polyolefin produced by the above production method.

Specifically, the olefin-based polymer is a copolymer comprising a repeating unit represented by the following formula (4) and a repeating unit represented by the following formula (5), and contains at least 3 mol% of a polar functional group derived from a polar monomer.

[Chemical Formula 4]

[Chemical Formula 5]

In the above formulas 4 and 5, R ⁵ , Y and p are the same as defined above,

R is each independently a hydrogen atom or a straight or branched aliphatic hydrocarbon group having 1 to 18 carbon atoms, and specifically methyl, ethyl, n-propyl, isopropyl, 2-methylpropyl, n-butyl, Butyl, t-butyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, pentyl, neopentyl, n-hexyl, , Octyl, decyl or dodecyl.

The polymer may exhibit various physical properties depending on the polar functional group (Y) in the polymer. For example, when the polar functional group is a carboxyl group or a carboxylic acid ester group, the polymer may exhibit adhesiveness to a metal or a polar resin (nylon, EVOH, etc.) It has excellent compatibility, water dispersibility and oil resistance. Such an improvement effect can be determined by the content of the polar functional group such as the carboxyl group contained in the polymer. Specifically, the olefinic polymer according to one embodiment of the present invention may contain at least 3 mol%, more specifically 3 to 11 mol%, and more specifically, 3 to 5 mol% of the polar functional group. Generally, the content of a specific functional group such as a polar functional group in a polymer can be measured by a nuclear magnetic resonance method or an infrared spectroscopic method. In the present invention, the content is measured by infrared spectroscopy.

The olefin-based polymer may contain constitutional units other than the repeating units of the formulas (4) and (5) within the range not impairing the object of the present invention.

Examples of the optionally contained constituent units include cyclic olefins other than the monomer of Formula 2, nonconjugated polyenes, hydroxyl group-containing ethylenically unsaturated compounds, amino group-containing ethylenically unsaturated compounds, epoxy group-containing ethylenic unsaturated compounds, aromatic vinyl compounds , Unsaturated carboxylic acids and derivatives thereof, vinyl ester compounds, or vinyl chloride. When these constituent units are contained, these amounts are 10 mol% or less based on all the constituent units constituting the polar group-containing olefin copolymer.

The above-mentioned additional structural unit may be added together with the addition of the ethylenically unsaturated monomer during the production of the polyolefin.

The olefin-based polymer can have a higher molecular weight than the olefin-based polymer prepared by using the metallocene compound as a catalyst by using the metallocene compound having excellent catalytic activity of the formula (1). Specifically, when the polymerization process is carried out under the condition that hydrogen is not added, the weight average molecular weight (Mw) of the produced polyolefin may be 100,000 to 600,000 g / mol, more specifically 300,000 to 600,000 g / mol. Further, when the polymerization process is carried out under the condition of adding hydrogen, for example, when the polymerization process is carried out under the condition of adding 0.37 L of hydrogen under 1 atm of the reactor condition, the resulting polyolefin has a weight average molecular weight (Mw) of 10,000 To 300,000 g / mol, more specifically from 10,000 to 100,000 g / mol.

The molecular weight distribution (Mw / Mn) of the polyolefin may be 3.3 or less, more specifically 1.2 to 3. When the molecular weight distribution (Mw / Mn) is 3 or less, the olefin polymer is excellent in the orientation of the carboxyl group or the carboxylic acid ester group in the polymer at the interface between the polymer and the polar material, It is excellent in compatibility with materials.

In the present invention, the weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were determined from the results obtained by measurement in 140 ° C in o-dichlorobenzene solvent using GPC (gel permeation chromatography).

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[ Example  1: Production of olefinic polymer]

0.16 M of 10-undecenoic acid in 50 ml of toluene was contacted with 0.32 M of triisobutylaluminum as an organoaluminum compound in the glass beads for 10 minutes. The resulting reaction product was placed in a stainless steel reactor having a capacity of 100 ml and 10 mM of methyl aluminoxane (MAO, Al / Zr = 3000) and 0.02 mM of a metallocene catalyst (PI) having the following structure were added thereto as a cocatalyst . The temperature of the reactor was heated to 60 DEG C and the pressure in the reactor was then filled up to 5 atm with ethylene. The polymerization was carried out for 10 minutes so that ethylene was continuously supplied at a pressure of 5 atm, followed by the addition of 10 ml of ethanol to terminate the polymerization. After the reactor was cooled, the product was recovered and dried in a vacuum oven at 60 DEG C for 8 hours to obtain an olefinic polymer.

The activity of the catalyst and the content of repeating units derived from comonomers in the polymer were measured from the prepared polymer. Specifically, the activity of the catalyst was determined from the molar ratio of the catalyst to the total amount of the produced olefinic polymer, and the content of the polar functional group, that is, the carboxyl group, in the olefinic polymer was calculated by infrared spectroscopy. Table 1 shows the results.

(PI)

(PI)

[ Comparative Example  1: Production of olefinic polymer]

As shown in the following Table 1, the same procedures as in Example 1 were carried out except that the polymerization was carried out at 25 캜. However, no polymer was produced.

[ Comparative Example  2: Preparation of olefin-based polymer]

As shown in the following Table 1, 0.48 M of 10-undecenoic acid (UDA), 0.48 M of triisobutylaluminum (TIBA) and 25 ml of toluene were used as the comonomer, and the polymerization was carried out at 60 ° C Was carried out in the same manner as in Example 1. < tb >< TABLE > However, no polymer was produced.

[ Comparative Example  3 to 5: Preparation of olefin-based polymer]

A polymer was prepared in the same manner as in Example 1, except that the conditions were as shown in Table 1 below. The catalyst activity and the carboxyl group content as a polar functional group in the polymer were measured in the same manner as in Example 1 above.

The catalyst (mM) Ethylene (bar) Comonomer (M) TIBA (M) toluene
(ml) Temperature
(° C) Activity (kg / mmol · hr) Content of carboxyl group (mol%) Example 1 0.02 5 UDA (0.16) 0.32 50 40 4.3 3 Example 2 0.02 5 UDA (0.16) 0.32 50 60 5.5 3 Example 3 0.02 5 UDA (0.08) 0.16 50 60 5.4 3 Example 4 0.02 5 UDA (0.32) 0.64 50 60 8.6 4 Example 5 0.02 5 UDA (0.48) 0.96 25 60 10.8 5 Example 6 0.02 5 UDA (0.48) 0.72 25 60 9.2 4 Comparative Example 1 0.02 5 UDA (0.16) 0.32 50 25 - - Comparative Example 2 0.02 5 UDA (0.48) 0.48 25 60 - - Comparative Example 3 0.02 5 AA (0.16) 0.32 50 60 - - Comparative Example 4 0.02 5 MA (0.16) 0.32 50 60 - - Comparative Example 5 0.01 5 PA (0.02) 0.04 900 60 4.2 -

In Table 1, the meanings of the abbreviations in English are as follows:

UDA: 10-undecenoic acid

TIBA: Triisobutyl aluminum

AA: Acrylic acid

MA: methyl acrylate

PA: pentanoic acid

As a result of preparing olefinic polymers under the conditions shown in Table 1, Examples 1 to 6 were able to easily produce polymers having carboxyl groups by using metallocene compounds having excellent catalytic activity. However, in Comparative Example 1 in which the polymerization temperature was as low as 25 占 폚, Comparative Example 2 in which the content ratio of the comonomer and the organoaluminum compound was 1: 1, and Comparative Example 3 in which the carbon number of the straight chain hydrocarbon group between the carboxyl group and the ethylene group was less than 8 4, it was impossible to prepare a polymer into which an intramolecular carboxyl group was introduced. However, in the case of Comparative Example 5 using pentanoic acid as a comonomer, it was possible to produce a polymer, but no carboxyl group was present in the polymer produced.

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, And falls within the scope of the invention.

Claims (12)

Preparing a mixture by mixing a polar monomer having a polar functional group and a linear hydrocarbon group having a carbon number of 8 or more in the molecule of Formula 2 with an organoaluminum compound in a molar ratio of 1: 1.5 to 1: 3; And
Polymerizing the polar functional group in the polymer at a temperature of 40 to 80 DEG C in the presence of an olefin polymerization catalyst comprising a metallocene compound represented by the following formula 1 after mixing the ethylene monomer with the above mixture, % ≪ / RTI >
[Chemical Formula 1]

(2)

(In the above formulas (1) and (2)
M is a Group 4 transition metal;
A is silicon (Si);
R ¹ is an alkyl group having 1 to 4 carbon atoms;
R ² is an alkyl group having 1 to 4 carbon atoms;
R ³ and R ^{3 '} are each independently an alkyl group having 1 to 20 carbon atoms;
R ⁴ and R ^{4 '} are each independently an aryl group having 6 to 18 carbon atoms;
R ⁵ is a linear alkanediyl group having 8 to 20 carbon atoms;
Each X is independently halogen;
Y is a carboxyl group or a carboxylic acid ester group,
n is an integer of 1 to 6,
p is an integer of 1 to 3, and when p is 2 or 3, each Y is the same or different)
delete The method according to claim 1,
Wherein the polar monomer is 10-undecenoic acid.
The method according to claim 1,
Wherein the organoaluminum compound is a compound represented by the following general formula (3).
(3)
(R _{a) m} AlZ _{3 -m}
(3)
Ra is a hydrocarbon group of 1 to 12 carbon atoms,
Z is a halogen atom or a hydrogen atom, and
and m is an integer of 1 to 3)
5. The method of claim 4,
Wherein the organoaluminum compound is triisobutylaluminum.
5. The method of claim 4,
Wherein the polar monomer and the organoaluminum compound are mixed in a molar ratio of 1: 1.5 to 1: 2.
The method according to claim 1,
Wherein the catalyst for olefin polymerization comprises a metallocene compound represented by the following formula (1a).
[Formula 1a]

(Ph in the above formula (1a) is a phenyl group)
The method according to claim 1,
Wherein the catalyst for olefin polymerization is supported on a support selected from the group consisting of silica, silica-alumina and silica-magnesia.
The method according to claim 1,
Wherein the catalyst for olefin polymerization further comprises a cocatalyst of alkylaluminoxane.
10. The method of claim 9,
Wherein the alkylaluminoxane is methylaluminoxane.
A polyolefin produced by the process according to claim 1, wherein the polyolefin contains at least 3 mol% of polar functional groups in the polymer.
12. The method of claim 11,
A polyolefin comprising from 3 mol% to 5 mol% of an intramolecular polar functional group.