JPS6026408B2 - Method for producing ethylene copolymer - Google Patents

Description

Detailed Description of the Invention The present invention relates to a method of copolymerizing ethylene and a small proportion of Q-olefin having 3 or more carbon atoms to produce a low-density ethylene copolymer. It is known that when a certain proportion of Q-olefin is polymerized, an ethylene copolymer having a density comparable to that of high-pressure polyethylene can be obtained.

Generally, since the polymerization operation is easy, it is advantageous to employ high-temperature dissolution polymerization in which polymerization is performed using a hydrocarbon solvent at a temperature higher than the melting point of the produced polymer. However, in order to obtain a copolymer with a sufficiently large molecular weight, the viscosity of the polymerization solution increases, so the concentration of the polymer in the solution must be reduced, and therefore the amount of copolymer per polymerization vessel must be reduced. The drawback is that productivity is inevitably low.
On the other hand, when attempting to obtain the above-mentioned low-density ethylene copolymer by the slurry polymerization method that is often used in the production of high-density polyethylene, the copolymer easily dissolves or swells in the polymerization solvent, resulting in an increase in the viscosity of the polymerization solution. However, due to the adhesion of the polymer to the walls of the polymerization vessel and the reduction in the bulk density of the polymer, it was not only impossible to increase the slurry concentration, but also the continuous operation for a long time was impossible.

Furthermore, the resulting copolymer was sticky, which caused problems in terms of quality. Several methods have been proposed to overcome these drawbacks by using multi-stage polymerization. For example, according to Hakama-Seki No. 51-52487, a special catalytic component consisting of a co-pulverized product of magnesium halide, titanium compound, and aluminum halide ether is used to produce 5 ta or more of ethylene per night. This disclosure discloses a method in which copolymerization is carried out in a low-boiling hydrocarbon having a boiling point of 40° C. or lower. However, this method has limitations on the polymerization solvent that can be used. Also, Tokuseki Showa 52-
According to No. 121 Madarabi, a method is proposed in which a similar polymerization solvent is used and a complicated three-stage polymerization is performed, but it has drawbacks such as the need to control the polymerization solvent and the need for complicated polymerization operations. . Further, Tokukan Sho 52-12408 discloses a method of prepolymerizing 50 or more ethylene per supported catalyst per night, followed by copolymerization in the polymerization solvent. In addition to the above-mentioned drawbacks, this method produces too much ethylene homopolymer in the prepolymerization, so that fish eyes are unavoidable when the copolymer is used in film applications. According to these prior art techniques, it was also essential to carry out prepolymerization using ethylene. The present inventors have been able to use solvents with relatively high boiling points, such as hexane and heptane, which are often used in olefin polymerization, as polymerization catalysts, and can produce high-density and large copolymers with simple operations. After studying a slurry polymerization method, they found that this goal could be achieved by strictly specifying the catalyst components and prepolymerization conditions, and by using ethylene and Q-olefin in the prepolymerization.

That is, the present invention comprises: (1) copolymerizing ethylene and a small proportion of Q-olefin having 3 or more carbon atoms at a temperature of 100°C or lower using a catalyst formed from a titanium catalyst component supported on a magnesium compound and an organoaluminum compound; In the method for producing an ethylene copolymer having a density of 0.900 to 0.945 mm/〆, as component (■) (A
-1) The specific surface area is 40 μm or more, the average particle size is in the range of 5 to 200 μm, and the geometric standard deviation of the particle size distribution.

(i) 0.01 titanium catalyst component per titanium catalyst component is used in advance. or 50
Preliminary copolymerization of ethylene and Q-olefin having 3 or more carbon atoms is carried out so that a copolymer having a Q-olefin content of 0.2 to 4% by weight is formed, (ii) ethylene and carbon are then copolymerized; It is necessary to carry out the main polymerization of Q-olefins having a number of three or more, by changing (i) the polymerization conditions in the preliminary copolymerization to (ii) different polymerization conditions from the polymerization conditions in the main polymerization, and changing the polymerization rate of the preliminary copolymerization to (ii) the main polymerization. at least 1/5 of the polymerization rate of
This is a method for producing an ethylene copolymer, which is characterized by the following steps.

The titanium catalyst component supported on the magnesium compound used in the present invention must meet one or both of the following requirements. In other words, (A-1) the specific surface area is 4
Specific force/ta or more, the average particle diameter is in the range of 5 to 200 μm, and the geometric standard deviation of the particle size distribution.

and/or 2) have a specific surface area of 80 w/ta or more, and must contain an organic acid ester of 0.1 to 7 times the mole of titanium. (A
A titanium catalyst component that satisfies the requirements of -1) has a specific surface area of 40 w/ta or more, preferably 60 w/ta or more, an average particle size in the range of 5 to 200, and a geometric standard for particle size distribution. deviation.

The average temperature is less than 2.1, preferably 1.95 or less. Here, a light transmission method was used to measure the particle size distribution of titanium catalyst component particles. Specifically, 0.0 in an inert solvent such as decalin
The catalyst component is diluted to a concentration of around 1 to 0.5%, placed in a measurement cell, and the cell is illuminated with a narrow light to continuously measure the intensity of light passing through the liquid in a settled state with particles. Measure the particle size distribution. Standard deviation based on this particle size distribution. is determined from the lognormal distribution function. Note that the average particle diameter of the catalyst is shown as a weight average diameter, and the particle size distribution was calculated by sieving within a range of 10 to 20% of the weight average particle diameter. Preferably, these titanium catalyst components have a relatively regular shape such as a spherical shape, an elliptical spherical shape, or a flake shape.

In order to obtain these titanium catalyst components, magnesium in the above-mentioned form is prepared in advance so that the average particle size is in the range of 5 mm to 200 mm, and the geometric standard deviation of the particle size distribution is 2.1 or less, preferably 1.95 or less. It is preferable to prepare the compound in advance and suspend it in an excess liquid titanium compound or a hydrocarbon solution of the titanium compound to support it. Alternatively, by selecting the reaction conditions between the titanium compound and the magnesium compound, catalyst particles having a narrow particle size distribution such that the average particle size of the catalyst component to be produced satisfies the above range may be formed. A method for producing such a catalyst component is described, for example, in Japanese Patent Publication No. 5013.
27pi No. 49-65999, Japanese Patent Application Laid-open No. 52-Shige No. 590, Tokubetsu No. 52-107704, and Japanese Patent Application Laid-open No. 53-21093. Alternatively, it can be obtained by reacting a Grill compound and a silicate ester, and in some cases, further reacting with a halogenating agent and then reacting with a titanium compound. Generally, a method for producing a titanium catalyst component supported on a magnesium compound by co-pulverizing a magnesium compound and a titanium compound is known.
In many cases, the specific surface area is small, the particle size distribution is wide, and the shape is irregular, so they cannot be used as they are and require operations such as classification. If a copolymer that does not satisfy the requirements of (2) and has a particle size outside the above range is used, a high-density, large copolymer cannot be obtained. Even if it does not satisfy the condition (A-1) as a titanium catalyst component, it has a specific surface area of 80/ta or more,
It can be used in the present invention if the organic acid ester is contained in an amount of 0.1 to 7 moles as much as titanium.

In this case, it is more preferable if the condition (1) is also satisfied. The organic acid ester-containing titanium catalyst component is useful for the highly stereoregular polymerization of Q-olefins such as propylene, and its production method is summarized, for example, in Samurai Seki Sho 53-30 No. 1.

Alternatively, it can be obtained by reacting a reaction product of a Grignard compound and a silicate ester with an organic acid ester and, in some cases, a halogenating agent, and then reacting with a titanium compound. As disclosed in the above applications, the magnesium compounds used in the synthesis of the titanium catalyst component include magnesium halides, alkoxymagnesium, allyloxymagnesium, magnesium oxide, magnesium hydroxide, magnesium carbonate, hydrotalcite, Grignard compounds, and many other compounds.

In some cases, magnesium metal is used. In addition, the titanium compound used in the synthesis of the titanium catalyst component is often a tetravalent titanium compound, and titanium tetrahalide or titanium alkoxyhalide is often used, and among them, titanium tetrahalide such as titanium tetrachloride is used. is the most commonly used. The attachment of titanium to a magnesium compound is often carried out with the aid of one or more of various electron donors, organometallic compounds, silicon compounds, and the like. The titanium catalyst component corresponding to (A-1) above usually contains 0.5 to 15% by weight of titanium, particularly 1 to 1% by weight, and contains 1/2 to 1/2 of titanium magnesium (atomic ratio). 10u, especially 1/3 to 1/50, halogen/titanium (molar ratio) is 4 to 200, especially 6, and 10
It is in the range of 0.

Further, its specific surface area is usually 40 m/ta or more, particularly 60 m/ta or more. In addition, the titanium catalyst component corresponding to (A-2) above usually contains 0.3 to 1% by weight of titanium, especially 0.6% to 1% by weight, and the titanium/magnesium (atomic ratio) is 1/2% by weight. , and 1/100, especially 1/4
to 1/7Q halogen/titanium (atomic ratio) is 4 to 200, especially 6 to 10u organic acid esterno titanium (
molar ratio) is in the range of 0.1 to 7, preferably 0.2 to 6, and the specific surface area is usually 80〆/ta or more,
Preferably, it indicates the 100th to 800th/day. Further, as the organic acid ester, aliphatic carboxylic acid ester, alicyclic carboxylic acid ester, aromatic carboxylic acid ester, lactone, carbonic acid ester, etc. can be used.

More specifically, methyl acetate, butyl acetate, vinyl acetate,
Aliphatic carboxylic acid esters such as ethyl probionate, isopropyl butyrate, cyclohexyl acetate, phenyl acetate, pendyl acetate, methyl chloroacetate, methyl methacrylate, methyl laurate, methyl stearate, methyl cyclohexanecarboxylate, ethyl cyclohexanecarboxylate, etc. alicyclic carboxylic acid esters, methyl benzoate, ethyl benzoate, isopropyl benzoate, n-butyl benzoate, vinyl benzoate, cyclohexyl benzoate, phenyl benzoate, methyl toluate, ethyl toluate, methyl anisate, Aromatic carboxylic acid esters such as ethyl anisate, dimethyl phthalate, methyl chlorobenzoate, y-butyrolactone, 6-valerolactone,
Examples include coumarin, lactones such as phthalide, and carbonic acid esters such as ethylene carbonate. They do not necessarily need to be used by themselves during the synthesis of the catalyst component; the ester component may be formed during the synthesis of the catalyst component, for example, as may be necessary by combining a compound having an alkoxy group with an acid halide. As the organoaluminum compound 'B}, at least one A in the molecule
Compounds having an I-carbon bond are available, for example...the general formula R is also AI(OR2)nHPXq (where RI and R
2 is a hydrocarbon group containing usually 1 to 13 carbon atoms, preferably 1 to 4 carbon atoms, and may be the same or different from each other.

X is a halogen, m is 0<mS3, n is OSn<3, p is 0≦p<3, q is a number such that 0≦q<3, but m
+n + p + q = 3), (ii) Group 1 metal represented by the general formula MIAIR (where MI is Li, Na, k, and RI is the same as above) and the key alkylate of aluminum, (ii
i) Examples include rust compounds of magnesium and aluminum. Examples of the organoaluminum compounds belonging to (i) above include the following.

General formula RimAI(OR2)3-m, where RI and R2 are the same as above, m is preferably the number of 1.5SmS3. General formula RimAIX3-m (where RI is the same as above, X is halogen, m is preferably 0<m<3), general formula RimAIH3-m (here RI is the same as above, m is preferably 2 m<3), general formula R
imAI (OR2) gunwale q (here RI and R2 are the same as before, X is halogen, 0<mS3, 0≦n<3, 0≦q
<3, and m+n+q=3). Magnesium compounds belonging to (i) include, more specifically, trialkylaluminum such as triethylaluminum and triptylaluminium, trialkenylaluminum such as triisoprenyleraluminum, dialkylaluminum such as diethylaluminium ethoxide, dibutylaluminum butoxide, etc. In addition to alkyl aluminum sesquialkoxides such as alkoxide, ethyl aluminum sesquiethoxide and butyl aluminum sesquipoxy, R. 5 mountains (OR2) o. Partially alkoxylated aluminum alkyls having an average composition such as Alkylaluminum sesquihalogenides such as ethylaluminum sesquibromide, ethylaluminum dichloride,
Partially halogenated alkyl aluminum dihalides such as propyl aluminum dichloride, butyl aluminum dibromide etc., dialkyl aluminum hydrides such as diethylaluminum hydride, dibutyl aluminum hydride, ethyl aluminum dihydride, propyl aluminum dihydride etc. Partially hydrogenated alkyl aluminums such as alkyl aluminum dihydrides such as hydride, partially alkoxylated and halogenated alkyl aluminums such as ethyl aluminum ethoxy chloride, butyl aluminum butoxy chloride, ethyl aluminum ethoxy bromide.

Further, as a compound similar to..., an organoaluminum compound in which two or more aluminum atoms are bonded via an oxygen atom or a nitrogen atom may be used. Examples of such compounds include (C2 ratio) 2 mountains OA1 (C2Q)2, (C4day9)2
AIOA1(C4day9)2, etc. can be exemplified. Examples of compounds belonging to the above (ii) include LiN (C2 ratio), LiA1 (C7,5)4, etc. Among these, it is particularly preferable to use trialkylaluminum and/or alkylaluminum halide. In the invention, ethylene and Q-olefin are precopolymerized in an inert hydrocarbon medium using the components (1) and {B), and 0.01 to 50 days per night of the titanium catalyst component, preferably Copolymers of from 0.02% to 20%, particularly preferably from 0.05 to 1.0%, are prepared.

In the preliminary copolymerization, the polymerization conditions are different from those in the main polymerization, and the average polymerization rate is set to 1/5 or less, preferably 1/10 or less, particularly preferably 1/20 or less of the average polymerization rate in the main polymerization. Although it varies depending on the type of the carrier component, the polymerization rate in the prepolymerization is usually less than 500 tons/hour, preferably less than 300 tons/hour.
It is preferable to set it to hr or less. In addition, in the main polymerization, the polymerization rate is usually at least 500 t/ta component/hr, preferably at least 1000 t/t component/hr, and particularly preferably at least 200 t/t component/hr.
It is preferable to set it to 0M/ta component/hr or more. The polymerization rate can be controlled by, for example, the polymerization temperature, the olefin combination rate, the ratio of component (B) to component (2), and the like.

In preliminary copolymerization, it is especially important to lower the polymerization temperature, slow down the olefin feed rate, or
- The polymerization rate can be easily adjusted by reducing the amount of the component used. Inert hydrocarbon solvents used for prepolymerization include propane, butane, n-bentane, isobentane, n-hexane, isohexane,
Aliphatic hydrocarbons such as n-heptane, n-octane, isooctane, n-decane, n-dodecane, kerosene, alicyclic hydrocarbons such as cyclobentane, methylcyclobentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene Examples include aromatic hydrocarbons such as methylene chloride, ethyl chloride, ethylene chloride, halogenated hydrocarbons such as chlorobenzene, and aliphatic hydrocarbons, especially aliphatic hydrocarbons having 4 to 10 carbon atoms. Hydrocarbons are preferred.

In prepolymerization, the amount of titanium catalyst component air per night in the inert solvent, converted to titanium atoms, was 0.001% and 5%.
00 mmol, especially 0.005, preferably 20 mmol, and the organic aluminum compound field should have an AI/Ti (atomic ratio) of 0.1, 1000, especially 0.5, and 500. It is preferable to use it in a proportion.

The prepolymerization temperature is preferably 75°C or less, particularly 120° to 6°C. Q-olefins having 3 or more carbon atoms used in the present invention include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1 -Tetradecene, 1-octadecene, and other carbon atoms having less than 1 carbon number are preferred, and among them, those having less than 3 carbon atoms and 10 carbon atoms are particularly preferred.

As the Q-olefin having 3 or more carbon atoms used in the prepolymerization, it is not necessarily necessary to use the same Q-olefin as that used in the main polymerization, but it is generally preferable to use the same Q-olefin. In the prepolymerization, the above-mentioned Q-olefin is preliminarily copolymerized so that the amount of the Q-olefin in the copolymer is 0.2% to 4% by weight. Furthermore, its density is 0.9
It is preferable to polymerize ethylene and Q-olefin so that the polymerization rate is about 0.00 to 0.950 m/mass. Hydrogen may be present in the prepolymerization. In the present invention,
Using the above premixed catalyst, ethylene and Q-olefin having 3 or more carbon atoms are copolymerized to have a density of 0.900 to 0.
．． Group 5/Produce the final copolymer.

Copolymerization is less than 10C, preferably 40%, 890%
It is carried out under non-melting conditions of the polymer at a temperature of . The copolymerization is carried out in the form of slurry polymerization in a hydrocarbon medium or gas phase polymerization in the absence of liquid hydrocarbons. In particular, the present invention can exhibit even more remarkable effects when applied to slurry monopolymerization. As the hydrocarbon medium, the above-mentioned inert hydrocarbons or Q-olefins are used. Particularly preferred are aliphatic hydrocarbons, with those having 3 to 12 carbon atoms being particularly preferred. In particular, a great advantage of the present invention is that good results can be obtained even when using a solvent with a boiling point of more than 4.0 mm. The catalyst concentration in slurry polymerization is 0.001 to 0 in terms of titanium catalyst component W per hour of liquid phase and titanium atoms.
．． 1 mmol, preferably 0.003 mmol, preferably 0.1 mmol, and the organoaluminum compound concentration is preferably such that the aluminum titanium (atomic ratio) is in the range of 2 to 2,000, preferably 10 to 1,000. . In order to obtain a density within the above range, Q-olefin is added in the polymer in an amount of about 0.2 to 30% by weight, particularly about 0.3 to 25% by weight, although it varies depending on the type of catalyst and the type of Q-olefin. It is sufficient if it is contained.

For this purpose, the amount of Q-olefin to be fed may be determined depending on the polymerization pressure, polymerization temperature, and other polymerization conditions. The polymerization pressure is generally about 1 to 100 kg/unit. In order to control the molecular weight of the polymer, a molecular weight regulator such as hydrogen can be added to the polymerization system. Or, for the purpose of improving catalytic activity or adjusting molecular weight distribution,
Compounds such as boron, silicon, tin, etc. may be added to the catalyst system. These can also be used by forming adducts, rust compounds or reactants with the Tsukuda component in advance.
The main polymerization of the present invention may be carried out in two or more stages under different conditions.

Example 1 Catalyst Synthesis> In a nitrogen stream, 1 mol of commercially available metal magnesium was added to 500 g of dehydrated hexane, 1.1 mol of tetraethoxysilane was added, and the temperature was raised to 65° C. under a clear atmosphere.

After raising the temperature, add a small amount of methyl iodine and iodine, followed by n
- After dropping 1.2 mol of butyl chloride over 2 hours 7
At 030, I prayed for three hours. After the reaction was completed, it was washed repeatedly with hexane. Subsequently, 0.25 mol of ethyl benzoate was added and reacted at 60 qo for 1 hour. After extracting the top solution, 10 mol of titanium tetrachloride was added and the reaction was carried out at 120 qo for 2 hours. After extracting the titanium tetrachloride, titanium tetrachloride was further reacted under the same conditions to carry out titanium loading. After the reaction was completed, the solid portion was washed repeatedly with hexane. When the composition of the obtained solid was analyzed, it was found that each solid had T.
They were 9 for j29, 3 for Mg205, 9 for CI650, and 9 for ethyl benzoate 87. The average particle diameter of the Ti catalyst component was 18.6 mm, and the geometric standard deviation of the particle distribution was 18.6 mm.

The specific surface area was 1.51, and the specific surface area was 230. <Polymerization> The Ti catalyst component obtained by the above method is calculated as 3 Ti atoms.
The catalyst was diluted with dehydrated and purified hexane to a concentration of 1 hmol/hmol, and triethylaluminum was added to it.
2 hmol was added per lmmol of i atoms.

Subsequently, butene-16. Ethylene containing melon hol% was supplied, and ethylene-butene-1 equivalent to 0.23 sulfur per solid catalyst was reacted for 20 minutes, and the catalyst was pretreated with ethylene-butene-1. Ta.
Separately, 1 part of the dehydrated and purified solvent hexane was placed in the autoclave, and the inside of the autoclave was sufficiently purged with nitrogen, and then 1.9 hmol of triethylaluminum and the catalyst pretreated with ethylene/butene-1 were added to titanium atoms. Add 0.01 mmol in terms of conversion, then insert 1 kg/h of hydrogen, make the total pressure 5 x 9/h, and add butene-1.
6.6 while continuously adding ethylene containing 8 hol%.
When polymerization was carried out for 2 hours at a temperature of
I got 77 evenings.

The density of the obtained polymer was 0.928 mm/kg, and the amount of dissolved polymer in the hexane solvent was 3.4 wt%. Examples 2 to 15 When using the catalyst prepared by the method of Example 1 and changing the pretreatment conditions with ethylene and Q-olefin,
Tables 1 and 1-2 show examples in which the polymerization solvent for ethylene and q-olefin was changed and the type of Q-olefin was changed under various conditions.

■ Ship ■ Satoshi;, Kata fake Hijiri Isoro S ■ To * Rendokoro ■ Domo key F Ant-proof ■ To * Good point ■ To for Examples 16 to 20 <Catalytic synthesis> In the method of Example 1 Catalysts were synthesized using various esters instead of ethyl benzoate, and after pretreatment with ethylene-butene-1 in exactly the same manner as in Example **1, ethylene and butene-1 were synthesized under the same polymerization conditions as in Example 1. Copolymerization of Putene-1 was carried out.

The results obtained are shown in Table 2. Table 2 Example 21 <Catalyst synthesis> In a nitrogen stream, 2 moles of commercially available anhydrous magnesium chloride were suspended in 40% dehydrated and purified hexane, and 12 moles of ethanol was added dropwise over 2 hours while holding a light, and then the mixture was diluted to 70 qo. The mixture was reacted for 1 hour.

To this, 5.75 mol of diethyl aluminum chloride was added dropwise at room temperature, and the mixture was left for 2 hours. Next, titanium tetrachloride 3
．． 4 mol was added dropwise, and the reaction was carried out at room temperature for 2 hours. After the reaction was completed, the solid portion produced was washed repeatedly with hexane.
The composition of the obtained solid was 9/ter solid of Ti54, C and 5
75 o/night-solid, Mg190, rail 1 ter solid, OE
A total of 165 p/ter solids were present in each case.

The specific surface area of the solid catalyst was 280/solid, the average catalyst particle size was 12.1, and the geometric standard deviation of the particle size distribution of the catalyst particles was 1.48. <Polymerization> 2 Dehydrated and purified solvent hexane 1 in the autoclave
After filling the autoclave with sufficient nitrogen, add triethylaluminum 2. 0.01 mol of the above solid catalyst in terms of titanium atoms was added, and the catalyst was pretreated for 2 minutes at 30° C. under normal pressure while inserting ethylene containing 16.3 hol% of butene.

The pretreatment amount corresponds to 5.2 nights of ethylene per night of catalyst. Subsequently, the temperature inside the autoclave was raised to 65q0, hydrogen 1.0k9/kg was added, and ethylene containing n-butene-16.3 mol% was continuously added with the total pressure being 4k9/kg. However, when polymerization was carried out for 2 hours at 6yo, the bulk specific gravity was 0. Madaratano d, melt index 0.
A speckled copolymer 249 was obtained. The density of the obtained copolymer was 0.928 m/m, and the amount of dissolved polymer in the solvent hexane was 4.1 wt%. Example <Catalyst synthesis> Commercially available magnesium hydroxide 2K9 having a specific surface area of 67〆/unit was suspended in water and heated to 500 rpm using a homomixer with a turbine stator. Toazusa treatment was performed for 1 hour under /m conditions.

Next, apply this water slurry of magnesium hydroxide to the bottom of the fly frame.
When the temperature rose to 0 qo and a two-fluid nozzle with a diameter of 0.2 mm was installed, the mixture was atomized using a mist dryer in parallel flow with hot air at 200° C. to obtain spherical magnesium hydroxide. Next, a pith separation operation was performed to obtain 20 to 63 mounds. The magnesium hydroxide thus obtained had a specific surface area of 86 w/w and was spherical in shape. Thirty tons of spherical magnesium hydroxide obtained by the above procedure was inserted into 400 mm titanium tetrachloride, and the reaction was carried out at 13 mm for 2 hours.

After the reaction was completed, titanium tetrachloride was extracted, and then washed repeatedly with hexane. When the obtained solid was analyzed for its composition, it was found that 19 Ti atoms, 360 magnesium atoms, and 290 chlorine atoms were lost per night of the solid.
Subsequently, 30 g of the solid obtained by the above method was collected into a three-necked flask which had been sufficiently purged with nitrogen, and 1.50 g of kerosene was added thereto. After dropping 4 times the mole (47.8 hmol) of Ti supported with ethyl benzoate at a reaction temperature of 30q0, the mixture was heated at 30° C. for 1 hour. Subsequently, 1/2 mole of diethyl aluminum chloride of ethyl benzoate was added dropwise under the reaction condition of 300°C, and the temperature was increased to 3000°C for 1 hour after the dropwise addition.
I worshiped the lights. After that, the kerosene as a solvent was extracted by the Enoki method, and after washing twice with 150 liters of kerosene, the titanium tetrachloride 150
was added, and the reaction was carried out at 130qC for 2 hours. It was then washed repeatedly with hexane. When the composition of the obtained solid was analyzed, it was found that 20 Ti atoms per night of the solid.
Females also had 9 out of 310 for chlorine, 9 out of 330 for Mg, and 9 out of 9 for ethyl benzoate. The average particle diameter of the obtained catalyst was 37 mm, and the geometric standard deviation of the catalyst particle size distribution. The specific surface area of the Noma 1.4 catalyst was 90/m2. <Polymerization> The Ti catalyst component obtained by the above method is calculated as 2 Ti atoms.
The catalyst was diluted with dehydrated and purified hexane to a concentration of 1 hmol/hmol, and triethylaluminum was added to it.
3 hmol was added per lmmol of i atom.

Subsequently, ethylene containing 8 hol% of butene-1 was supplied at normal pressure of 4 pi○, and 0.40 hol% of ethylene-butene-1 was reacted with each solid catalyst for 5 minutes to convert the catalyst into a mixed gas of ethylene and butene-1. Preliminary treatment was carried out. Separately, after thoroughly purifying the inside of the autoclave with nitrogen, 2.0 hmol of triethylaluminum and 0.02 hmol of the pretreated catalyst in terms of titanium atoms were added, followed by 1 hmol of hydrogen.
．． When polymerization was carried out at 60°C for 2 hours while continuously adding ethylene containing 17.9 hol% of putene at a total pressure of 6X9/G, the cage specific gravity was 0.38/G. A sheet of ethylene copolymer 3 with a melt index of 1.2 was obtained. The density of the obtained ethylene copolymer was 0. It was 9 pieces/lump, and the dissolved polymer in the solvent hexane was 4.5 wt%. Example 23 <Catalyst synthesis> n-Butylmagnesium.

A solution of 100 n-butyl ether containing 0.1 mol of lido was inserted into the flask, and it was added dropwise to this in a N2 stream over 1 hour at room temperature, and then the temperature was slowly raised to 65 qo.
The solid magnesium compound obtained after reacting for 1 hour was washed repeatedly with hexane.

Subsequently, 0.025 mol of ethyl benzoate was added, and 60 mol of ethyl benzoate was added.
Reaction was carried out for 1 hour at qC. After the obtained solid was filtered, titanium tetrachloride of 10 Z/solid was added and reacted at 110 qo for 2 hours. After the reaction was completed, it was washed repeatedly with hexane. When the composition of the obtained solid was analyzed, it was found that 9 of Ti24, 9 of Mg215m9, 9 of CI640,
The amount of ethyl benzoate was 82. The average particle size of the catalyst is 18.3 French, and the geometric standard deviation of the catalyst particle size distribution. Noma 1.
The specific surface area of the 68 catalyst was 187〆/unit. <Polymerization> 2 Dehydrated and purified solvent hexane 1 in the autoclave
After filling the autoclave with sufficient nitrogen, add triethylaluminum 2. 0.018 hmol of the above solid catalyst in terms of titanium atoms was added, and the catalyst was pretreated for 3 minutes while inserting ethylene containing 8.5 hol% butene-1 at 3000 °C under normal pressure.

The amount of pretreatment corresponds to 7.1 nights of ethylene per night of catalyst. Next, the temperature inside the autoclave was raised to 65°C, 1.5 kg of hydrogen was added to the autoclave, and ethylene containing 18.5 hol% of n-butene was continuously added at a total pressure of 6k9/kg. Polymerization was carried out at 65q0 for 2 hours while adding a large amount of water to obtain 294 ml of ethylene copolymer having a bulk specific gravity of 0.39 ml and a melt index of 2.5. The density of the obtained ethylene copolymer was 0.929 m/sakaki, and the amount of dissolved polymer in the solvent hexane was 4.7 wt%. Example 24 Catalyst synthesis> Commercially available anhydrous magnesium chloride 20 and ethyl benzoate 6
．． 0 skin and stainless steel (15 ribs in diameter) in a nitrogen atmosphere.
Internal volume 8 containing SUS-302) ball Ion hard
The mixture was placed in a stainless steel container with an inner diameter of 10 mm and co-pulverized for 50 hours using a vibrating mill Ryoreki with a capacity of 70 mm.

The obtained solid treated product was suspended in titanium tetrachloride,
After reacting for 2 hours at 0qo, solid components were filtered out and washed repeatedly with hexane. When the composition of the obtained solid catalyst component was analyzed, it was found that Ti21 female and Mg2 female per solid overnight.
9 out of 10, chlorine 670 female, ethyl benzoate Satoshi mo. Moreover, the catalyst average particle diameter of the obtained Ti catalyst component was 17.
8. Geometric standard deviation of catalyst particle size distribution. The specific surface area of the catalyst for Panama 2.2 was 185〆/unit. <Polymerization> The Ti catalyst component obtained by the above method was treated with butene-18. Pretreatment was carried out for 5 minutes with ethylene containing 2 hol %, and 0.30 hours of ethylene-butene-1 was reacted per night of the solid catalyst.

Separately, in the same manner as in Example 1, using the same autoclave, ethylene containing 17.1 mol% of buteso was continuously added and polymerization was carried out at 7000 for 2 hours, resulting in a cage specific gravity of 0.
265 ethylene copolymers with a melt index of 1.3 were obtained.

The density of the obtained copolymer was 0.927 m/m, and the amount of dissolved polymer in the solvent hexane was 5.5 m/m. The fence was t%. Comparative Example 1 <Catalyst Synthesis> 20 kg of commercially available anhydrous magnesium chloride was placed in a stainless steel (SUS-302) ball 1 with a diameter of 15 mm in a nitrogen atmosphere.
The mixture was placed in a stainless steel container with a content neck of 800 mm and a diameter of low, containing 0 q of solids, and pulverized for 5 q hours in a vibrating mill device with a capacity of 7 G.

The obtained solid treated product was suspended in titanium tetrachloride and
After reacting at °C for 2 hours, solid components were filtered off and washed repeatedly with hexane. When the composition of the obtained solid catalyst component was analyzed, it was found that Tilo p, Mg23 per solid overnight
513, chlorine 730M. In addition, the average catalyst particle diameter of the falsified Ti catalyst component was 12.2 μm, and the geometric standard deviation of the catalyst particle size distribution. The specific surface area of the catalyst was 55 m/m. <Polymerization> In the same manner as in Example 1, 0.39 kg/night of catalyst was added in advance.
The sample was pretreated with ethylene containing 15.0 hol% of butene.

When copolymerization of ethylene and butene-1 was carried out using the pretreated catalyst under the same conditions as in Example 1, an ethylene copolymer with a bulk specific gravity of 0.19 y/y and a melt index of 2.1 was obtained. I got 115 evenings. The density of the obtained copolymer is 0
．． The polymer was 939 y/m/m, and the dissolved polymer was 16.8 wt % with respect to the solvent hexane, and the bulk specific gravity and yield were both excellent results. Comparative Example 2 <Catalyst Synthesis> Commercially available anhydrous magnesium chloride 23, titanium tetrachloride 2.
4 evening, aluminum chloride diphenyl cable key body 4.
A stainless steel bowl with a diameter of 15 mm was heated for 2 nights in a nitrogen atmosphere.
The mixture was placed in a stainless steel container with an internal volume of 800 m and a diameter of 10 m and containing 100 m² of ion solids, and was pulverized for 24 hours using a vibrating mill device at maximum capacity.

When the composition of the obtained solid was analyzed, it was found that the solid had a Ti of 20, a M of 9 of 10, and a CI of 0 of 9 per night. In addition, the catalyst average particle diameter of the obtained Ti catalyst component was 13.8 particles,
Geometric standard deviation of catalyst particle size distribution. The specific surface area of the catalyst was 29〆/unit. <Polymerization> As in Example 1, the catalyst was pretreated with ethylene containing 16.5 hol% of butene equivalent to 0.41 sulfur per night of catalyst.

When copolymerization of ethylene and butene-1 was carried out using the pretreated catalyst under the same conditions as in Example 1, an ethylene copolymer with a high specific gravity of 0.25 mm/base and a melt index of 1.9 was obtained. I got 130 nights of union. The density of the obtained copolymer was 0.936 mm/block, and the amount of dissolved polymer in the solvent hexane was 9.2 M%, resulting in poor bulk density and yield. Comparative Example 3 Using the catalyst prepared by the method of Example 21, copolymerization of ethylene and butene-1 was carried out under the same conditions as in Example 21 without performing pretreatment with a premixed gas of ethylene and butene-1. As a result, an ethylene copolymer having a bulk specific gravity of 0.30 mm and a melt index of 1.3 was obtained.

The density of the obtained polymer was 0.931 mm/kg, and the amount of dissolved polymer in the solvent hexane was 9. powder't%,
Bulk specific gravity! Both solid polymer yields decreased. Example
25 Into an autoclave (equipped with a rope handle) having an internal volume of 8, 500 μm of sodium chloride was added as a catalyst dispersant, and the system was sufficiently purged with nitrogen.

The temperature of the system was raised, and ethylene gas containing 5.56 mol% of 4-methylbentene was added at 60 parts per hour and hydrogen was added at 1 hour.
The joint effort was made to maintain the pressure of 5k9 blocks G at the end of 0 states/ratio. Ti pretreated with 2.5 mmol of toisobutylaluminum and ethylene knobte-1 of Example 1.
The catalyst was added to the system in an amount of 0.02 o-atoms in terms of Ti atoms. 7 pi 0 and the above flow rate and pressure 5k9/
Polymerization was carried out for 1 hour while supplying gas to maintain the swimming G.

The yield of the obtained copolymer was 94 mm, and the bulk specific gravity was 0.36.
Evening/earth, MI is 0.6 tano 10', density of polymer is,
0.926 evening/It was an enemy. Comparative Example 4 <Catalyst Synthesis> Two moles of commercially available anhydrous magnesium chloride were suspended in five dehydrated and purified hexane in a nitrogen stream, and 12 moles of ethanol was added dropwise over 2 hours while stirring, and then 1 mole of ethanol was added at room temperature. Time reacted.

5. A mol of diethyl aluminum chloride was added dropwise at room temperature, and the mixture was allowed to stand for 2 hours. Subsequently, after adding 15 moles of titanium tetrachloride, the temperature of the system was raised to 80 qo, and the reaction was carried out for 3 hours while heating. The generated solid portion was separated by sieving and washed repeatedly with purified hexane. Furthermore, by removing the coarse part by classification, the catalyst average particle diameter is 2.
1v, geometric standard deviation of the particle size distribution of catalyst particles.

In the evening, 1.87 liters of catalyst was obtained. The composition of the obtained solid was 67 wc/ter solid as Ti atoms and 640 m as CI atoms.
o/ter solid, 1801 M/ter solid as Mg atoms,
There were 95 o/1 solids each present as an OEt basis. Further, the specific surface area of the solid was 240〆/unit. <Polymerization> Polymerization was carried out under the conditions of Example 21.

The amount of ethylene and butene-1 pretreated was 6.3 nights per night of titanium catalyst component.

Claims (1)

[Scope of Claims] 1. Using a catalyst formed from (A) a titanium catalyst component supported on a magnesium compound and (B) an organoaluminum compound, ethylene and a small proportion of an α-olefin having 3 or more carbon atoms are mixed into 100% In a method for producing an ethylene copolymer having a density of 0.900 to 0.945 g/cm_2, which is copolymerized at a temperature below °C, as component (A), (A-1) has a specific surface area of 40 cm_2/g or more, and an average The particle size is in the range of 5 to 200μ, the geometric standard deviation σg of the particle size distribution is less than 2.1, and/or (A-2) the specific surface area is 80m_2/g or more, and contains an organic acid ester. (i) 0.01 to 50 per gram of titanium catalyst component in advance;
(ii) Preliminary copolymerization of ethylene and an α-olefin having 3 or more carbon atoms is carried out so that a copolymer having an α-olefin content of 0.2 to 40% by weight in g is formed; It is necessary to carry out the main polymerization of α-olefins of 3 or more, and (i) the polymerization conditions in the preliminary copolymerization are changed to (
ii) A method for producing an ethylene copolymer, which is different from the polymerization conditions of the main polymerization, and is characterized in that (i) the polymerization rate of the preliminary copolymerization is at least 1/5 or less of the rate of (ii) the main polymerization. 2 The amount of copolymerization in main polymerization is 100% of the amount of preliminary copolymerization.
The method according to claim 1, wherein the amount is doubled or more.