KR100648502B1 - Method for producing olefin copolymer having high transparency by gas phase polymerization using ziegler-natta catalyst including aryloxy groups - Google Patents

Abstract

The present invention relates to a method for preparing a highly transparent olefin copolymer by gas phase polymerization, and more particularly, a transition metal compound of Group IV, Group V, or Group VI having at least 4 oxidized cycles in which at least two aryloxy group ligands are bonded. Is reacted with an organomagnesium compound to reduce the oxidation to a transition metal compound of 3, using a Ziegler-Natta catalyst for olefin polymerization, and gas phase polymerization using a specific molar ratio of hydrogen and comonomers relative to ethylene. It relates to a method for producing an olefin copolymer.

Aryloxy groups, Ziegler-Natta, catalysts, gas phase, polymerization, olefins, copolymers, high transparency

Description

METHODE FOR PRODUCING OLEFIN COPOLYMER HAVING HIGH TRANSPARENCY BY GAS PHASE POLYMERIZATION USING ZIEGLER-NATTA CATALYST INCLUDING ARYLOXY GROUPS}

The present invention relates to a method for preparing a highly transparent olefin copolymer by gas phase polymerization, and more particularly, a transition metal compound of Group IV, Group V, or Group VI having at least 4 oxidized cycles in which at least two aryloxy group ligands are bonded. Is reacted with an organomagnesium compound to reduce the oxidation to a transition metal compound of 3, using a Ziegler-Natta catalyst for olefin polymerization, and gas phase polymerization using a specific molar ratio of hydrogen and comonomers relative to ethylene. It relates to a method for producing an olefin copolymer.

In the olefin polymerization reaction in which olefins are polymerized using a transition metal compound as a catalyst, US Patent No. 4,894,424 discloses a method for producing an ethylene polymer and an ethylene copolymer using a trivalent Group IV transition metal compound. The catalyst is composed of transition metal compounds of IV, V, VI having at least tetravalent oxides, for example, titanium compounds having a structure of Ti (OR) _m Cl _n , magnesium (Mg) and alkyl chlorides (RCl). It is prepared by a reduction reaction with a Grignard compound having a structure of RMgCl made (formula 1).

Ti (OR) _m Cl _n + RMgX → (RO) _m-1 TiCl _n : (Formula 1)

(Wherein R = C ₁ to C ₆ alkyl, X is a halogen, and m + n = 4)

Since such a catalyst is a catalyst produced by a reduction reaction by a Grignard compound, at least 80% of the titanium metal contained in the catalyst is present in a trivalent oxidation state (Ti ³⁺ ).

In recent years, many examples of using an aryloxy ligand in a non-metallocene catalyst have been reported. J. Am. Chem. Soc. On page 117 3008, a compound in which a 1,1'-bi-2,2'-naphthoxy ligand (1,1'-bi-2,2'-naphthol) is bound to a titanium or zirconium transition metal, and derivatives thereof are disclosed. A catalyst for olefin polymerization used is disclosed, and Japanese Patent Laid-Open Nos. Hei 6-340711 and EP 0606125 A2 disclose that a halide ligand of a titanium halide and a zirconium halide compound is substituted with a chelated phenoxy group to produce a high molecular weight polymer. However, a chelate catalyst for olefin polymerization having a narrow molecular weight distribution is disclosed. In addition, in the US Macromolecules No. 15, page 5069 and No. 30, 1562, the bis-phenolato ligand titanium compound as a main catalyst and ethylene polymerization using methylaluminoxane (MAO) as a promoter Catalysts are disclosed.

However, the conventional non-metallocene-based chelating catalyst for olefin polymerization using titanium and zirconium compounds has the disadvantage of using expensive MAO or boron compounds as cocatalysts, and two aryloxy groups Since the structure is connected, it is not easy to manufacture and change.

The present invention, in order to solve the problems of the prior art as described above, by introducing two or more aryloxy group ligands that are not connected to each other in the catalyst molecule, exhibits the effect of introducing the aryloxy group ligand and at the same time facilitate the production and modification thereof By gas phase polymerization, without using expensive MAO or boron compounds as cocatalysts, but using a Ziegler-Natta catalyst for olefin polymerization with significantly increased activity over known trivalent Group IV transition metal compound catalysts. It is an object to provide a method for producing a highly transparent olefin copolymer.

According to the present invention, in the presence of a Ziegler-Natta catalyst for olefin polymerization as a main catalyst, a method for producing an olefin copolymer by gas phase reaction of a gas phase polymerization composition comprising hydrogen, ethylene and a comonomer, The Ziegler-Natta catalyst for olefin polymerization is a general formula MX _{p- (q + r)} (OAr ₁ ) _q (OAr ₂ ) _r (wherein M is a transition group of Group IV, Group V, or Group VI having at least 4 oxidation. , X is a halogen element, Ar ₁ and Ar ₂ is an aryl group or substituted aryl group having 6 to 30 carbon atoms, Ar ₁ and Ar ₂ are the same or different, and are not connected to each other, p is the oxidation of M And a transition metal compound represented by 0 or more, and represented by 0 ≦ q ≦ p, 0 ≦ r ≦ p and 2 ≦ q + r ≦ p, and a general formula MgX _2-m R _m , wherein X is a halogen element , R is an alkyl group having 1 to 16 carbon atoms and 0 <m≤2) The content ratio of the hydrogen and the ethylene contained in the gas phase polymerization composition, which is made by a manufacturing method including the condensation, is 0.05 to 0.5 in a molar ratio of hydrogen / ethylene, and the content ratio of the comonomer and the ethylene is Provided is a method for producing an olefin copolymer by gas phase polymerization, wherein the comonomer / ethylene is 0.1 to 0.5 in molar ratio.

The method for producing an olefin copolymer according to the present invention will be described in more detail below.

Preferred embodiments of the present invention are organomagnesium halides (RMgX) or organomagnesium (MgR) made by the Grignard method with a transition metal compound substituted with an aryloxy group to increase the activity of the catalyst, as illustrated in (Formula 2). _It relates to a method for producing an olefin copolymer by gas phase polymerization using a Ziegler-Natta catalyst for olefin polymerization prepared by a reduction reaction with an organomagnesium compound such as ₂ ).

Ti (OAr) _m Cl _n + RMgX → (ArO) _m-1 TiCl _n : (Formula 2)

Wherein m is an integer of at least 2, n is an integer, m + n = 4, R = C ₁ -C ₆ alkyl, Ar = C ₆ -C ₃₀ aryl, or substituted aryl)

Preferred embodiments for the preparation of Ziegler-Natta catalysts used as main catalysts in the process for preparing olefin copolymers according to the invention are as follows.

For polymerization of olefins a Ziegler used in the present invention-Natta catalyst, in an aliphatic hydrocarbon solvent such as heptane, preferably, an alkyl halide or tetrahydrofuran, the formula in the presence of an electron donor compound such as ethers MX _{p- (q + r)} (OAr ₁ ) _q (OAr ₂ ) It can be prepared by reacting the transition metal compound represented by _r and the organomagnesium compound represented by the general formula MgX _2-m R _m .

In the above reaction, the reaction does not occur smoothly if the reaction temperature is less than 60 ℃, the reaction is too active if the temperature exceeds 90 ℃ difficult to remove the heat. Therefore, it is preferable that reaction temperature is 60-90 degreeC.

In the transition metal compound, M is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, or the like, and the transition metal of Group IV, Group V, or VI of the periodic table of 4 or more, wherein the oxidation value is 4 It is preferable that it is Ti.

In the transition metal compound, X is F, Cl, Br or I as the halogen element, Cl, Br or I is preferable, and Cl is more preferable.

In addition, and according to the transition metal compound, an aryloxy group Ar ₁ and Ar ₂ are contained in the transition metal compound to increase the activity of the catalyst, Ar ₁ and Ar ₂ is an aryl group containing 6 to 30 carbon atoms or a substituted aryl group, Ar ₁ and Ar ₂ are the same as or different from each other, are not connected to each other, and two or more aryloxy groups are included in one molecule of the transition metal compound.

In the organomagnesium compound, X is F, Cl, Br or I as the halogen element, Cl or Br is preferable, R is an alkyl group having 1 to 16 carbon atoms, and 0 <m ≦ 2.

The organomagnesium compound may be prepared by reacting a metal magnesium with an alkyl halide represented by halogen or a general formula RX at -20 to 150 ° C, more preferably at 60 to 90 ° C. Here, R and X are the same as those defined in the organomagnesium compound, in which case the reactants are preferably reacted in the following molar ratios.

0.5≤alkyl halides / Mg≤10

More preferably

1≤alkyl halide / Mg≤2

The reaction between the transition metal compound and the organic magnesium compound is preferably carried out in the presence of an alkyl halide represented by the general formula RX. Wherein R and X are the same as defined in the organomagnesium compound. These compounds are preferably used in the following molar ratios.

0.1≤transition metal compound / organic magnesium compound (RMgX) ≤0.5 and

1≤alkyl halide / organic magnesium compound (RMgX) ≤2

or

0.1 ≦ transition metal compound / organic magnesium compound (MgR ₂ ) ≦ 0.5 and

2 ≦ alkyl halide / organic magnesium compound (MgR ₂ ) ≦ 4

If the molar ratio of the transition metal compound / organic magnesium compound is less than 0.1, sufficient polymerization activity cannot be obtained, and if it exceeds 0.5, it is difficult to control the reduction reaction at a desired level.

Depending on the solvent used or other needs, the organomagnesium compound can be used in the form of a complex with an electron donor compound such as ether.

Aliphatic hydrocarbons used in the preparation of catalysts include hexane, heptane, propane, isobutane, octane, decane, kerosene and the like, with hexane or heptane being particularly preferred. The electron donor compounds used in the preparation of the catalyst include methyl formate, ethyl acetate, butyl acetate, ethyl ether, tetrahydrofuran, dioxane, acetone, methyl ethyl ketone, and the like, and tetrahydrofuran or ether is preferable.

In the method for producing an olefin copolymer according to the present invention, in the presence of a Ziegler-Natta catalyst for olefin polymerization as described above as a main catalyst, a gas phase reaction is carried out by gas phase reaction of a composition for gas phase polymerization comprising hydrogen, ethylene and a comonomer. Prepare coalescing.

In the method for producing an olefin copolymer according to the present invention, the hydrogen contained in the gas phase polymerization composition is used to adjust the molecular weight of the resulting copolymer, and the content ratio of hydrogen and ethylene is a mole ratio of hydrogen / ethylene. And 0.05 to 0.5, preferably 0.15 to 0.25. If this hydrogen / ethylene molar ratio is less than 0.05 or more than 0.5, the molecular weight of the copolymer is too low or too high, making product application difficult.

In addition, in the method for preparing an olefin copolymer according to the present invention, the comonomer included in the gas phase polymerization composition is alpha- other than ethylene such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and the like. An olefin is preferable, and the content ratio of the comonomer and the ethylene is 0.1 to 0.5 in a molar ratio of comonomer / ethylene, preferably 0.27 to 0.35. If this comonomer / ethylene molar ratio is less than 0.1 or more than 0.5, the desired level of copolymer cannot be obtained.

This is because when the content of the comonomer in the gas phase polymerization composition is too small, the crystal size is partially increased in the copolymer during processing, thereby reducing the transparency. On the other hand, when the content of the comonomer is too high, the softening point of the copolymer (softening temperature) is lowered because the reaction stability in the gas phase polymerization reactor is less.

In the method for producing an olefin copolymer according to the present invention, as a promoter, the general formula AlR _n X _(3-n) (wherein R is an alkyl group having 1 to 16 carbon atoms, X is a halogen element, and 1≤n≤3) Alkyl aluminum compound represented by) can be used further.

As said alkyl aluminum compound, Preferably triethyl aluminum, trimethyl aluminum, tri normal propyl aluminum, tri normal butyl aluminum, triisobutyl aluminum, tri normal hexyl aluminum, tri normal octyl aluminum, tri 2-methyl pentyl aluminum, etc. are mentioned. Among them, triethyl aluminum, trinormal hexyl aluminum or trinormal octyl aluminum are particularly preferable.

It is preferable to use the said alkylaluminum compound at the time of gas phase superposition | polymerization in the following molar ratio according to desired polymer property.

0.5 ≦ alkyl aluminum compound / transition metal in main catalyst ≦ 500

More preferably

0.5≤alkylaluminum compound / transition metal in main catalyst≤100

If the molar ratio of the transition metal in the alkylaluminum compound / main catalyst is less than 0.5, sufficient polymerization activity cannot be obtained, whereas if it exceeds 500, the adverse effect of lowering the polymerization activity appears.

In the method for producing an olefin copolymer according to the present invention, the polymerization reaction is preferably performed in the absence of a hydrocarbon solvent at a temperature of preferably 60 to 120 ° C, more preferably 65 to 100 ° C, even more preferably 70 to 80 ° C. Preferably it is carried out by gas phase polymerization at a pressure of 2 to 80 atmospheres, more preferably 4 to 40 atmospheres.

 If the polymerization temperature in the gas phase fluidized bed reactor is less than 60 ° C, sufficient polymerization efficiency cannot be obtained, and if it exceeds 120 ° C, there is a problem that a polymer mass is easily generated. In addition, when the operating pressure in the gas phase fluidized bed reactor is less than 2 atm, the heat capacity per unit volume is too low to obtain a sufficient polymerization efficiency, and if it exceeds 80 atm, it becomes difficult to control the reaction and impose a heavy load on the reactor.

The catalyst system used in the method for producing an olefin copolymer according to the present invention may be configured by various methods. That is, the catalyst is a solid catalyst composed of a transition metal such as titanium, magnesium and halogen, which is directly added to the polymerization reactor, or is a form of a prepolymerization catalyst prepared by prepolymerization of one or more olefins in an inert liquid such as an aliphatic hydrocarbon. Can be added to the reactor. The cocatalyst alkylaluminum compound can be added directly to the polymerization reactor.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1

A. Catalyst Preparation

12.7 g (0.525 mol) of magnesium and 1.4 g (0.005 mol) of iodine were suspended in 450 ml of purified heptane in a 1 liter four-necked flask equipped with a mechanical stirrer. The temperature of the mixture was raised to 80 ° C., 56.6 g (0.12 mole) of bis (2,6-diisopropylphenoxy) titanium dichloride was dissolved in 150 ml of heptane, followed by 84.1 ml (0.8 of 1-chlorobutane). Mole) was added dropwise at a constant rate. After completion of the injection, a further reaction was carried out for 2 hours to obtain a catalyst. The catalyst obtained was washed four times with sufficient hexane and then stored in a slurry in purified hexane. The results of component analysis in the catalyst slurry are as follows.

Total titanium content in slurry: 4.4 wt%

Trivalent titanium oxide content in total titanium: 75% by weight

B. Prepolymerization

150 liters of normal-hexane were charged into a 200 liter stainless steel reactor equipped with a stirrer and a heating / cooling device. The reactor was thoroughly washed with pure nitrogen before use. Next, 874 ml of trinomalctylaluminum (TnOA) diluted in hexane at a concentration of 894 mmol-Al / liter was injected into the reactor as a cocatalyst and hexane at a concentration of 120 mmol-Ti / liter prepared in A as the main catalyst. 1600 ml of the catalyst slurry diluted in was injected into the reactor. Under stirring, prepolymerization was carried out at a temperature of 68 ° C. for 10 hours while feeding ethylene at a rate of 1.1 kg / hour and hydrogen at a rate of 0.27 g / hour. After the prepolymerization was completed, the prepolymerization catalyst was dried in a free flowing state by supplying the dried nitrogen to obtain 11.7 kg of the dried prepolymerization catalyst. The apparent density and average particle size of the obtained prepolymerization catalyst are as follows.

Bulk density: 0.32g / cc

Average particle size: about 280㎛

C. Vapor Phase Polymerization

In the presence of the prepolymerization catalyst prepared in B, the gas phase polymerization composition as shown in Table 1 was supplied to a fluidized bed reactor, and the gas phase polymerization reaction was carried out under the operating conditions shown in Table 1 below, and the rate of 10 kg / hour Ethylene / 1-butene copolymer was prepared. The amount of seed powder supplied to the fluidized bed reactor at the beginning of the reaction was 80 kg.

Physical properties such as melt index (MI), melt frow rate ratio (MFRR), density and Ti content of the prepared copolymer, and particle characteristics such as apparent density and average particle size were measured. A film was prepared from the copolymer prepared above, and its turbidity (HAZE (%)) and glossiness (GLOSS (%)) were measured, and the results are shown in Table 1.

Example 2

A. Catalyst Preparation

12.7 g (0.525 mol) of magnesium and 1.4 g (0.005 mol) of iodine were suspended in 600 ml of purified heptane in a 1 liter four-necked flask equipped with a mechanical stirrer. The temperature of the mixture was raised to 80 ° C., 53.3 g (0.12 mol) of bis (2-methyl-6-tertbutylphenoxy) titanium dichloride was dissolved in 150 ml of heptane, followed by 84.1 ml of 1-chlorobutane ( 0.8 mole) was added dropwise at a constant rate. After completion of the injection, a further reaction was carried out for 2 hours to obtain a catalyst. The catalyst obtained was washed four times with sufficient hexane and then stored in a slurry in purified hexane. The results of component analysis in the catalyst slurry are as follows.

Total amount of titanium in the slurry: 5.9 wt%

Trivalent titanium oxide content in total titanium: 79% by weight

B. Prepolymerization

A prepolymerization catalyst was prepared in the same manner as in Example 1, except that 1700 ml of a catalyst slurry diluted in hexane at a concentration of 128 mmol-Ti / liter prepared in A was used as the main catalyst, and dried prepolymerization. 12.6 kg of catalyst were obtained. The apparent density and average particle size of the obtained prepolymerization catalyst are as follows.

Bulk density: 0.32g / cc

Average particle size: about 270㎛

C. Vapor Phase Polymerization

In the presence of the prepolymerization catalyst prepared in B, the gas phase polymerization composition as shown in Table 1 was supplied to a fluidized bed reactor, and the gas phase polymerization reaction was carried out under the operating conditions shown in Table 1 below, and the rate of 10 kg / hour Ethylene / 1-butene copolymer was prepared. The amount of seed powder supplied to the fluidized bed reactor at the beginning of the reaction was 80 kg.

Physical properties such as melt index (MI), melt frow rate ratio (MFRR), density and Ti content of the prepared copolymer, and particle characteristics such as apparent density and average particle size were measured. A film was prepared from the copolymer prepared above, and its turbidity (HAZE (%)) and glossiness (GLOSS (%)) were measured, and the results are shown in Table 1.

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Comparative Example 1

A. Catalyst Preparation

12.7 g (0.525 mol) of magnesium and 1.4 g (0.005 mol) of iodine were suspended in 600 ml of purified heptane in a 1 liter four-necked flask equipped with a mechanical stirrer. The temperature of the mixture was raised to 80 ° C., 15.2 ml (0.056 mol) of titanium propoxide, 7.2 ml (0.065 mol) of titanium tetrachloride were added, and 84.1 ml (0.8 mol) of 1-chlorobutane were added dropwise at a constant rate. It was. After completion of the injection, a further reaction was carried out for 2 hours to obtain a catalyst. The catalyst obtained was washed four times with sufficient hexane and then stored in a slurry in purified hexane. The results of component analysis in the catalyst slurry are as follows.

Total titanium content in slurry: 7.3 wt%

Trivalent titanium oxide content in total titanium: 85% by weight

B. Prepolymerization

150 liters of normal-hexane were charged into a 200 liter stainless steel reactor equipped with a stirrer and a heating / cooling device. The reactor was thoroughly washed with pure nitrogen before use. Next, 818 ml of trinomalctylaluminum (TnOA) diluted in hexane at a concentration of 894 mmol-Al / liter was injected into the reactor as a cocatalyst, and hexane at 200 mmol-Ti / liter concentration, which was prepared in A as the main catalyst. 1800 ml of the catalyst slurry diluted in was injected into the reactor. Under stirring, prepolymerization was carried out at a temperature of 68 ° C. for 10 hours while feeding ethylene at a rate of 1.1 kg / hour and hydrogen at a rate of 0.38 g / hour. After the prepolymerization was completed, dried nitrogen was supplied to dry the prepolymerization catalyst in a free flowing state to obtain 10.9 kg of the dried prepolymerization catalyst. The apparent density and average particle size of the obtained prepolymerization catalyst are as follows.

Bulk density: 0.30g / cc

Average particle size: about 220㎛

C. Vapor Phase Polymerization

In the presence of the prepolymerization catalyst prepared in B, the gas phase polymerization composition as shown in Table 1 was supplied to a fluidized bed reactor, and the gas phase polymerization reaction was carried out under the operating conditions shown in Table 1 below, and the rate of 10 kg / hour Ethylene / 1-butene copolymer was prepared. The amount of seed powder supplied to the fluidized bed reactor at the beginning of the reaction was 80 kg.

Physical properties such as melt index (MI), melt frow rate ratio (MFRR), density and Ti content of the prepared copolymer, and particle characteristics such as apparent density and average particle size were measured. A film was prepared from the copolymer prepared above, and its turbidity (HAZE (%)) and glossiness (GLOSS (%)) were measured, and the results are shown in Table 1.

Comparative Example 2

In the presence of the prepolymerization catalyst prepared in B of Comparative Example 1, the composition for gas phase polymerization as shown in Table 1 was supplied to a fluidized bed reactor, and subjected to gas phase polymerization under the operating conditions shown in Table 1, 10 kg. Ethylene / 1-hexene copolymers were prepared at a rate of / hour. The amount of seed powder supplied to the fluidized bed reactor at the beginning of the reaction was 80 kg.

The physical properties such as melt index (MI), melt frow rate ratio (MFRR), density and Ti content of the prepared copolymer, and particle characteristics such as apparent density and average particle size were measured. A film was prepared from the copolymer prepared above, and its turbidity (HAZE (%)) and glossiness (GLOSS (%)) were measured, and the results are shown in Table 1.

TABLE 1

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Gas phase polymerization composition Hydrogen / ethylene molar ratio 0.15 0.15 0.17 0.35 Comonomer 1-butene 1-butene 1-butene 1-hexene Comonomer / ethylene molar ratio 0.27 0.29 0.29 0.19 Operating conditions Flow rate (cm / sec) 45 45 45 45 Polymerization temperature (℃) 78 78 78 80 Copolymer properties MI (g / 10 min) 1.0 1.0 1.0 1.0 MFRR 28 28 28 33 Density (g / cm 3) 0.918 0.918 0.918 0.917 Ti content (ppm) 9 10 19 19 Copolymer Particle Characteristics Apparent density (g / cc) 0.35 0.35 0.33 0.33 Average particle size (㎛) 1200 1200 1200 1200 Film properties HAZE (%) 15 15 30 30 GLOSS (%) 45 45 20 20

Note) MI: Melt Index,

Measured at 190 ° C under 2.16 kg / 10 min in accordance with ASTM D1238

MFRR: melt frow rate ratio,

MI (190 ℃, 21.6kg) / MI (190 ℃, 2.16kg)

HAZE (%): Average value measured 10 times per film sample according to ASTM D1003 after cutting specimen from turbidity and film formation

GLOSS (%): Glossiness, average value measured 10 times per film sample according to ASTM D2457 after cutting the specimen from the film

As can be seen from Table 1, the film prepared from the copolymer prepared according to Examples 1 to 2 of the present invention is prepared from the copolymer prepared by Comparative Examples 1 and 2 different from the present invention in the main catalyst. Compared to one film, it showed lower haze, meaning that it had better transparency.

In addition, the films made of the copolymers prepared in Examples 1 and 2 of the present invention showed remarkably excellent glossiness compared to the films made of the copolymers prepared in Comparative Examples 1 and 2, and the present invention In the copolymers prepared in Examples 1 to 2, the content of Ti in the copolymer was significantly less than that of the copolymer prepared in Comparative Example 1, which was used in Examples 1 to 2 of the present invention. It means that the polymerization activity of the catalyst was significantly superior to the polymerization activity of the main catalyst used in Comparative Example 1.

As described above, according to the present invention, an olefin copolymer having higher transparency, higher glossiness and less Ti content can be produced by gas phase polymerization.

Claims (5)

A method for producing a olefin copolymer by gas phase reaction of a gas phase polymerization composition comprising hydrogen, ethylene and a comonomer in the presence of a Ziegler-Natta catalyst for olefin polymerization as a main catalyst, wherein the Ziegler-Natta catalyst for olefin polymerization is General formula MX _{p- (q + r)} (OAr ₁ ) _q (OAr ₂ ) _r (wherein M is a transition group Group IV, Group V, or VI of the periodic table of at least 4, X is a halogen, and Ar ₁ and Ar ₂ are an aryl group or a substituted aryl group having 6 to 30 carbon atoms, Ar ₁ and Ar ₂ are the same or different, are not connected to each other, p is an oxidation value of M 4 or more, 0≤q≤ p, 0 ≦ r ≦ p and 2 ≦ q + r ≦ p, and a transition metal compound represented by general formula MgX _2-m R _m (wherein X is a halogen element and R is an alkyl group having 1 to 16 carbon atoms) And an organic magnesium compound represented by 0 <m ≦ 2). The content ratio of the hydrogen and the ethylene, which is produced by the preparation method and included in the gas phase polymerization composition, is 0.05 to 0.5 in a molar ratio of hydrogen / ethylene, and the content ratio of the comonomer and the ethylene is comonomer / ethylene. A method for producing an olefin copolymer by gas phase polymerization, characterized by a molar ratio of 0.27 to 0.5. The method of claim 1, wherein the transition metal compound and the organomagnesium compound is reacted at 60 ~ 90 ℃ at a molar ratio of 0.1≤ transition metal compound / organic magnesium compound ≤ 0.5, olefin copolymer prepared by gas phase polymerization Way. The alkyl of claim 1, represented by the general formula AlR _n X _(3-n) , wherein R is an alkyl group having 1 to 16 carbon atoms, X is a halogen element, and 1≤n≤3. An aluminum compound is further used, The method for producing an olefin copolymer by gas phase polymerization. The method for producing an olefin copolymer according to claim 3, wherein the alkylaluminum compound is used at a molar ratio of 0.5 ≦ alkylaluminum compound / transition metal ≦ 500 in the main catalyst. The method for producing an olefin copolymer according to claim 1, wherein the polymerization is carried out at a temperature of 60 to 120 ° C and a pressure of 2 to 80 atmospheres in the absence of a hydrocarbon solvent.