JPH0247113A - Production of ethylene polymer - Google Patents

Abstract

PURPOSE:To obtain the title polymer which does not undergo any decrease in heat sealability and scarcely suffers screen mesh plug due to extrusion residues and can be give a product of low contents of gel and fish eye by using an alcohol as a catalyst deactivator and adding a specified compound to the system. CONSTITUTION:Ethylene is polymerized or copolymerized with a 3-18C alpha-olefin by using a catalyst prepared from an Mg compound (e.g., ethyl-n- butylmagnesium), a Ti compound (e.g., tetrabutoxytitanium) and an organoaluminum compound (e.g., ethylaluminum sesquichloride) under conditions in which the formed polymer can dissolve in a reaction medium (e.g., n-hexane). A 1-4C alcohol is added to the reaction mixture to deactivate the catalyst and a compound selected from among a fatty acid metal salt, a fatty acid ester and a metal sulfonate (e.g., calcium strearate) is added to it. The title polymer which does not undergo any decrease in heat sealability, scarcely suffers screen mesh plug in the extruder and can give a product of low contents of gel and fish eye can be produced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing an ethylene polymer, and more specifically, it does not reduce heat-sealability, prevents clogging of screen mesh in an extruder, and prevents clogging of the screen mesh in an extruder. The present invention relates to a method for producing an ethylene polymer that is less likely to generate gels or fish eyes.

[Prior Art] A method of polymerizing ethylene, etc. using a Ziegler type catalyst under conditions where the produced polymer is dissolved in a hydrocarbon solvent is described, for example, in Japanese Patent Publication No. 1983-313:10 and Japanese Patent Publication No. 46-313:10.
:11968 Publication, Special Publication No. 47-1:172,
It is known from Japanese Patent Publication No. 19117. It is also known to deactivate the catalyst with alcohol, water, carboxylic acid, etc. Additionally, a method for removing the deactivated catalyst by passing it through an adsorbent column is disclosed in Canadian Patent No. 732279.
proposed in the specification. Furthermore, a method has been proposed in JP-A-57-121004, in which the catalyst is deactivated with a fatty acid metal salt after the polymerization is completed, and the entire amount of the reaction product between the catalyst and the fatty acid metal salt remains in the resulting polymer. ing.

[Problems to be Solved by the Invention] When the polymer is taken out from the polymer solution without deactivating the catalyst after the polymerization reaction is completed, the high molecular weight polymer is destroyed by the still active catalyst and residual monomer during that time. generate.

When a polymer-fixed ItjJ product containing such a high polymer is formed into a film, only a film containing many gels and fish eyes can be obtained.

Therefore, in order to prevent the formation of the high polymer, the catalyst is deactivated with alcohol and then the polymer is taken out. During this time, the reaction products of the catalyst and alcohol coagulate and grow. Loading the extruder with a polymer product containing this agglomerate increases screen mesh clogging in the extruder;
Moreover, many gels and fish eyes are generated in the product.

Furthermore, the method described in Canadian Patent No. 732,279 requires high equipment costs and operations such as replacing the adsorbent are complicated, resulting in high costs.

The method described in Japanese Unexamined Patent Publication No. 57-121004 has a problem in that the heat sealability of the film deteriorates. This is a reaction product between a catalyst and a fatty acid metal salt! &
This is thought to be due to substances bleeding onto the film surface.

The purpose of the present invention is to solve the problems of the prior art, and to develop an ethylene polymer that does not reduce heat sealability, prevents clogging of screen mesh in an extruder, and reduces occurrence of gels and fish eyes in products. The purpose is to provide a method for manufacturing.

[Means for Solving the Problems] As a result of intensive research to achieve the above object, the present inventors discovered that after deactivating the catalyst, a catalyst consisting of a fatty acid metal salt, a fatty acid ester, and a sulfonic acid metal salt was prepared. The present invention was achieved by discovering that it is sufficient to add at least one compound selected from the group.

That is, the present invention uses a catalyst obtained from a magnesium compound, a titanium compound, and an organoaluminum compound to react with ethylene or ethylene and an α-olefin having 3 to 18 carbon atoms under conditions such that the resulting polymer is dissolved in the reaction medium. After polymerizing, the catalyst is inactivated by adding an alcohol having 1 to 4 carbon atoms, and then at least one compound selected from the group consisting of fatty acid metal salts, fatty acid esters, and sulfonic acid metal salts. This is a method for producing an ethylene polymer characterized by adding.

The ethylene polymer in the present invention is obtained by polymerizing ethylene or ethylene and an α-olefin having 3 to 18 carbon atoms in the presence of a catalyst obtained from a magnesium compound, a titanium compound, and an organoaluminum compound.

The magnesium compound has a linear formula% formula% (wherein, R1 is an alkyl group having 1 to 18 carbon atoms,
It represents an alkoxy group, a cycloalkyl group, an alkylaryl group, an aryl group, an aryloxy group, an aralkyl group, or an arylalkoxy group, X represents a halogen atom, and n represents a real number satisfying 0≦n≦2. )
Compounds represented by can be mentioned.

Examples of the magnesium compound include methylmagnesium chloride, methylmagnesium bromide, ethylmagnesium chloride, ethylmagnesium bromide, ethylmagnesium iodide, propylmagnesium chlorite, propylmagnesium puromite, isopropylmagnesium chloride, butylmagnesium chloride, butylmagnesium bromide. , isobutylmagnesium chloride, 1-methylpropylmagnesium chloride, pentylmagnesium chloride, hexylmagnesium chloride and other alkylmagnesium halides: methoxymagnesium chloride, ethoxymagnesium chloride, ethoxymagnesium bromide, ethoxymagnesium iodite, propoxymagnesium chlorite, impropoxymagnesium Alkoxymagnesium halides such as chloride, butoxymagnesium chloride, 5ec-butoxymagnesium chloride, isobutoxymagnesium chloride, tert-butoxymagnesium chloride, pentyloxymagnesium chloride, hexyloxymagnesium chloride; phenoxymagnesium chloride, methylphenyloxymagnesium chloride, etc. Aryloxymagnesium halide: cyclobentylmagnesium chloride,
Cycloalkylmagnesium halides such as cyclohexylmagnesium chloride; Arylmagnesium halides such as phenylmagnesium halide and phenylmagnesium bromide; Alkylaryl or Aralkylmagnesium halide, dimethylmagnesium, dibutylmagnesium, dipropylmagnesium, diisopropylmagnesium, dibutylmagnesium, diisobutylmagnesium, di(l-
methylpropyl)magnesium, dibentylmagnesium, dihexylmagnesium, dioctylmagnesium, ethylmethylmagnesium, ethylpropylmagnesium, ethylisopropylmagnesium, ethyl-n-
Butylmagnesium, ethylisobutylmagnesium,
Dialkylmagnesiums such as ethyl (l-methylpropyl)magnesium and ethylpentylmagnesium; dialkoxymagnesiums such as dimethoxymagnesium, jetoxymagnesium, dipropoxymagnesium, diisopropoxymagnesium, and dibutoxymagnesium; dicycloalkylmagnesiums such as dicyclohexylmagnesium Diarylmagnesium such as diphenoxymagnesium: Diarylmagnesium such as diphenylmagnesium Di(methylphenyl)magnesium, dialkylaryl or diallkylmagnesium such as dibenzylmagnesium: Diarylalkoxymagnesium such as dibenzyloxymagnesium: Ethylmethoxymagnesium, ethyl Ethoxymagnesium, ethylpropoxymagnesium, ethylisopropoxymagnesium, ethylbutoxymagnesium, propylethoxymagnesium, isopropylethoxymagnesium, butylethoxymagnesium,
butylisopropoxymagnesium, butylbutoxymagnesium, ethylphenoxymagnesium, butylphenoxymagnesium, ethylcyclohexylmagnesium, propylcyclohexylmagnesium, butylcyclohexylmagnesium, ethylbenzylmagnesium, butylbenzylmagnesium, ethylphenylmagnesium, propylphenylmagnesium, butylphenylmagnesium, etc. Alkylmagnesium compounds:
Alkoxymagnesium compounds such as ethoxyphenoxymagnesium and butoxyphenoxymagnesium: Magnesium halides such as anhydrous magnesium chloride and anhydrous magnesium bromide: butyl isopropoxymagnesium chloride, butyl isopropoxymagnesium bromide, isopropylethoxymagnesium chloride, ethyl ethoxymagnesium chlorite, Examples include complex alkyl or arylmagnesium compounds such as butylbutoxymagnesium chloride, phenylethoxymagnesium chlorite, and phenylbutoxymagnesium chloride.

Among these are anhydrous magnesium chloride, ethyl-n-
Butylmagnesium etc. are preferred, especially ethyl-n-
Butylmagnesium and the like are preferred.

Note that these may be used alone.

Two or more types can be mixed or combined and used in combination.

As the titanium compound, the following formula % formula % (wherein, R2 has 1 to 10 carbon atoms, preferably 1
-6 alkyl group, cycloalkyl group, aryl group or aralkyl group, X is the same halogen atom as above, and m is usually an integer of 0.1 to 4, but is not necessarily an integer. It is a real number that satisfies O≦n≦4 as an average value of a mixture of various titanium compounds. ) can be used, specifically, for example.

Tetramethoxytitanium, tetraethoxytitanium.

Tetraalkoxytitanium represented by the general formula Ti(OR”)n, such as tetra-n-propoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, tetraisobutoxytitanium, tetracyclohexoxytitanium, tetraphenoxytitanium, TiCL ;La, TiB
r, , titanium tetrahalides such as Tits, (
Ctl+0)Tic sentence 3, (CJsO)TiC1:
+, (C:+HyOJTiCJL 3, (
n-C4119) Trihalogenated alkoxytitanium such as TiC1, (CJsO)TiBr+, (CHJ) 2T
ic sentence 2, (CJsO)2Tic look, (Cd2O
) aTiCu x, (n-c, n, o) ffric
41, dihalogenated titanium such as (CJ?0)2TiBrt, (CH30), TiCJl, (C2H60)3T
jcu z, (CJ, 0) iTici (n-c4n
9o)+TiC, (CtHsO)zTiBr, and other monohalogenated titanium. Among these, tetraalkoxytitanium represented by the general formula Ti(OR2)4 is preferred, and tetra-n-butoxytitanium is particularly preferred. These various titanium compounds may be used alone or in combination of two or more.

As the organoaluminum compound, there are various compounds, and a compound having at least one aluminum-carbon bond in one molecule can be used, for example, the following formula.

R', -, Ai X,, R': +-tAJL (OR'
)XL, R”3Al 2L (in the 1 formula, R3,
R4 represents an alkyl group or aryl group having 1 to 20 carbon atoms, X is the same as above, p represents 0.1 or 2,
t represents 0 or 1).

Examples of such organoaluminum compounds include diethylaluminum monochlorite, diisopropylaluminium monochlorite, diisobutylaluminum monochlorite, dioctylaluminum monochlorite, ethylaluminum dichlorite, isopropylaluminum monochlorite, ethylaluminum sesquichloride, and the like.

Among these, ethylaluminum sesquichloride and the like are particularly preferred.

These various organoaluminum compounds may be used alone or in combination of two or more.

The polymerization catalyst in the method of this invention is obtained by preparing the magnesium compound, the aluminum compound, and the titanium compound.

There are no particular restrictions on the method for preparing the catalyst, and for example, the magnesium compound, the organoaluminum compound, and the titanium compound may be separately added to a polymerization reaction volume of 1,000 ml, and then mixed.

A preferable preparation method includes, for example, a method of reacting the magnesium compound with the organoaluminum compound and mixing the resulting reaction product with the titanium compound.

This method is further detailed as follows: the magnesium compound and the organoaluminum compound are added to an inert solvent, and the temperature is e.g.
C, for example, by carrying out a contact reaction while stirring for a period of up to 1 hour.

The inert solvent used at this time is as follows.

Examples include aliphatic hydrocarbons having 5 to 16 carbon atoms, alicyclic hydrocarbons, aromatic hydrocarbons, etc. Specific examples include normal- or iso-pentane, hexane, heptane, octane, decane, dodecane, tetrodecane, Alternatively, cyclohexane, benzene, toluene, xylene, etc. may be mentioned.

Note that these solvents may be used alone or in combination of two or more.

Further, the ratio of the magnesium compound and the organoaluminum compound added here is not particularly limited, and may be appropriately adjusted within a range that provides the ratio of each metal component in the catalyst as described later.

There is no particular restriction on mixing the reaction product of the magnesium compound and the organoaluminum compound with the titanium compound. Atomic ratio)=o
, i to 200, especially within the range of 0.5 to 30, and aluminum/titanium (rX element ratio) = 1 to 200, especially 2
It is preferably within the range of 100 to 100. If the magnesium/titanium content is outside the above range, the activity of the catalyst will decrease,
If the aluminum/titanium ratio is less than 1, the activity of the catalyst will decrease, and even if the aluminum/titanium ratio is increased to more than 200, the catalytic activity proportional to the increase may not be obtained. Furthermore, if the ratio of magnesium/titanium or aluminum/titanium is outside the above range, the physical properties of the resulting polymer, particularly the film formability, may deteriorate, which is undesirable.

In the method of the present invention, during monopolymerization, the catalyst further includes:
It is also possible to use a known activator, such as a halide of an element belonging to Group I of the periodic table, as a polymerization catalyst system, and by doing so, it is possible to further enhance the catalytic activity.

Examples of the activator include halides of carbon, silicon, germanium, tin, lead, etc.
Specifically, for example, carbon halides such as methyl chloride, methyl iodide, methylene chloride, isopropyl chloride, 7-butyl chloride, carbon tetrachloride, silicon halides such as tetrachlorosilane, tin tetrachloride, etc. Examples include tin halides and lead halides such as lead tetrachloride. Among these various halides, carbon halides, particularly secondary and tertiary alkyl halides such as isopropyl chloride and t-butyl chloride, can be suitably used.

In addition, these activators can be used alone or in combination by mixing or combining two or more types.

Prior to polymerization, there are no particular restrictions on the procedure for blending the activator and the polymerization catalyst; for example, (1) the magnesium compound, the organoaluminum compound, the titanium compound, and the activator are separately placed in a ff1 reaction vessel. (2) When preparing the catalyst, an activator may be thoroughly mixed with any of the magnesium compound, organoaluminum compound, and titanium compound, and then other components of the catalyst may be mixed therein. (3) Also, when preparing the catalyst, a part of the activator is mixed with any of the magnesium compound, organoaluminum compound, and titanium compound, and then when other catalyst components are mixed and prepared, the magnesium compound, the organic A remaining amount of activator may be added to either the aluminum compound or the titanium compound.

In the present invention, the monomer may be ethylene alone, or an α-olefin having 3 to 18 carbon atoms may be used as a comonomer.

Examples of the α-olefin having 3 to 18 carbon atoms include linear or branched monoolefins and α-olefins substituted with an aromatic nucleus. Examples of α-olefins that can be used include linear monoolefins such as propylene, butene-1, hexene-1, octene-1, nonene-1, decene-1, undecene-1, and dodecene-1′:g. , 3-methylbutene-1,3-methylpentene-1,
4-Methylpentene-1,2-ethylhexene-1゜2
．． Examples include branched monoolefins such as 2,4-trimethyl-pentene-1 and monoolefins substituted with aromatic nuclei such as styrene.

Note that these olefins having 3 to 18 carbon atoms may be used alone or in combination of two or more.

In addition, in the present invention, along with the olefin having 3 to 18 carbon atoms, a small amount of 1.4-hexadiene and 1.9-
Diolefins such as decadiene can also be copolymerized.

Although the polymerization reaction is carried out in a reaction medium, it is important in the present invention to carry out the polymerization reaction under heating conditions such that the produced polymer is dissolved in the reaction medium.

As the reaction medium, aliphatic hydrocarbons, alicyclic hydrocarbons,
Inert solvents such as aromatic hydrocarbons can be used.

Specific examples include n-pentane, isopentane, hexane, isohexane, neohexane, heptane, isohebutane, octane, isooctane, nonane,
Alkanes such as isononane, decane, isodecane, undecane, dodecane, tetradecane, hexadecane; cyclopentane, cyclohexane, methylcyclohexane,
Examples include cycloalkanes such as ethylcyclohexane and dimethylcyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene. Among these, preferred are, for example, n-pentane, isopentane, n-hexane, isohexane, n-hebutane, isohebutane, n-octane, isooctane, n-decane, isodecane, cyclohexane, benzene, toluene, xylene, etc. Particularly preferred is n-hexane.

Note that these may be used alone or in combination of two or more.

The reaction temperature is the temperature at which the produced polymer dissolves in the reaction medium, and is usually tSO~250°C, especially 180~220°C.
It is 0°C. Such a polymerization temperature reduces the viscosity of the resulting polymer solution, which is convenient for the operation of the apparatus.

Other polymerization conditions include the physical properties of the desired polymer, the Qif used,
Although it cannot be determined uniquely depending on the type of fi-form, the catalyst concentration is usually O1~O1~10 in terms of titanium concentration.
mmol/day, preferably 0. Old ~ 1.0 mmol/l
It is. In addition, the reaction pressure is usually 10 to 150 Kg/c
m", particularly 20 to 70 Kg/cs2. Hydrogen or a molecular weight regulator such as diethylzinc may be present in the polymerization reaction system.

After carrying out the polymerization reaction for a predetermined period of time, known deactivators such as water, alcohols (e.g. methanol, ethanol, isopropyl alcohol, etc.), and carboxylic acids (e.g. formic acid, acetic acid, etc.) are used as catalyst deactivators. Propionic acid, benzoic acid, etc.) can be added to the reaction system to deactivate the catalyst; however, what is important in the present invention is that by adding an alcohol having 1 to 4 carbon atoms to the reaction system. be.

When an alcohol having 1 to 4 carbon atoms is used as a quenching agent,
A part of the deactivated reaction product with the catalyst becomes a low boiling point compound, which not only facilitates separation from the polymer, but also reduces gels and fish eyes in molded products of the resulting polymer.

Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, and isopropyl alcohol.

The amount of the alcohol added may be sufficient to deactivate the catalyst, for example, 10 to 1 mole of A1 of the catalyst.
~100 moles of alcohol may be added.

Note that alcohols having 1 to 4 carbon atoms may be used alone or in combination of two or more. moreover,
An antioxidant may be added together with the alcohol having 1 to 4 carbon atoms in order to prevent deterioration of the polymer at high temperatures.

In the present invention, it is important to add at least one sweep of a compound selected from the group consisting of fatty acid metal salts, fatty acid esters and sulfonic acid metal salts after the addition of the deactivator. Addition of these compounds prevents agglomeration of raw J& products generated by deactivation of the catalyst, and prevents gels and fish eyes from forming during polymer molding.

As the fatty acid metal salt, salts of alkali metals, alkaline earth metals, zinc, lead, etc. of fatty acids are used, and specifically, sodium stearate, calcium stearate, zinc stearate, sodium laurate, sodium myristate, etc. are used. , sodium palmitate, sodium stearate, sodium oleate, potassium oleate, calcium oleate, calcium 2-ethylhexanoate, zinc 2-ethylhexanoate, lead 2-ethylhexanoate, and the like. In addition to these, N-alkaline earth metal salts, ether carboxylic acid metal salts, etc. can also be used.

Preferred among the fatty acid metal salts are alkali metal salts of fatty acids having 6 to 20 carbon atoms, particularly 2-ethylhexanoic acid, undecanoic acid, uric acid, myristic acid,
Calcium salts such as palmitic acid, stearic acid, and oleic acid, more preferably 2-ethyl-
Calcium hexanoate and calcium stearate.

Examples of the fatty acid esters include glycerin esters of fatty acids such as lauric acid monoglyceride, stearic acid monoglyceride, and oleic acid monoglyceride, and sorbitan esters of fatty acids such as sorbitan lauric acid monoester and sorbitan oleic acid triester. . In addition to these, polyoxyethylene fatty acid esters, fatty acid esters of dihydric alcohols, etc. can also be used.

Among the various fatty acid esters mentioned above, glycerin esters of fatty acids are preferred, and stearic acid monoglyceride is particularly preferred.

Examples of sulfonic acid metal salts include alkylbenzenesulfonic acid salts such as sodium dodecylbenzenesulfonate and calcium dodecylbenzenesulfonate, and dialkylsulfosuccinic acid mJ! such as sodium sulfosuccinate di-2-ethylhexyl ester. 1 can be exemplified. In addition to these, higher alkyl sulfonates such as alkylnaphthalene sulfonates, formalin condensates of alkylaryl sulfonates, sodium dodecyl sulfonate, sulfonates of higher fatty acid esters such as Igebon A (trade name), and Igebon Sulfonic acid salts of higher fatty acid amides such as T (trade name) can also be used.

Among the various sulfonic acid metal salts, alkylbenzene sulfonate is preferred, and dodecylbenzene sulfonate is particularly preferred.

There is no particular restriction on the timing of adding the compound as long as it is after the deactivator has been added to the reaction system, or in general, after the alcohol has been added to the reaction system,
At a temperature and pressure such that the polymer concentration is about 80 to 95% by weight, the solvent, a part of the unreacted polymer, and a carbon number of 1 to
Before or after the flash operation to separate and remove volatile products of the reaction between the alcohol and the catalyst in step 4.

Preferably, the aforementioned compounds are added.

The amount added is 0.05 to 1.0 per mole of catalyst component.
If the amount added is too small, the effect of suppressing the formation of reaction products between the catalyst and alcohol will be insufficient, and if it is too large, the hue of the polymer will deteriorate or it may bleed onto the surface of the product film. This may lead to deterioration of physical properties.

The compound can be added to the polymer solution by dissolving or suspending it in the same solvent used for the polymerization reaction medium and feeding it to the polymer solution, for example by pump.

The polymer solution to which the compound has been added is supplied to a vented extruder, and after removing volatile substances such as the remaining solvent and unreacted additives, it is pelletized. At the outlet of this vented extruder, customary additives can be added to the polymer.

[Examples] Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

(Example 1) N-hexane solutions of ethylaluminum sesquichloride, butylethylmagnesium, and tetrabutoxytitanium were each added at 3.3-■ol/hour and 1.0 m
5ol/hour 1ull and Q, 15 mmol/hour were continuously supplied to a polymerization vessel with an internal volume of ill, and at the same time,
Ethylene 0.75Kg/hour, l-octene 0.5
For 87 hours, n-hexane was continuously supplied to the polymerization vessel at a rate of 6 sentences/hour, and the polymerization reaction was carried out under the conditions of a reaction temperature of 185° C., a reaction pressure of 0 kg, and 7 cm. Isopropyl alcohol was supplied to the polymer solution at a rate of 0.14 mol/hour to deactivate the catalyst. Unreacted ethylene and l-octene were then extracted from this solution in a flash tank.

After flash separation of volatile substances such as n-hexane,
Calcium stearate suspended in n-hexane was added to 0.
It was added to the polymer solution at a rate of 9 g/hour.

Thereafter, remaining 1-octene, n-hexane, etc. were separated and removed using a vented extruder to obtain an ethylene copolymer at a rate of 0.78 to 87 hours. At that time, the number of times the screen mesh clogging occurred in the extruder was measured.

The obtained ethylene copolymer was hot pressed into a film, and the particle size of the catalyst residue in the film was measured using a microscope.

Further, after adding additives to the copolymer, it was molded into a film using a T-die molding machine, the number of gels and fish eyes of 0.11 or more was counted, and the heat seal strength at 120°C was measured.

The results are shown in Table 1.

(Example 2) The same procedure as Example 1 was carried out except that stearic acid monoglyceride was used instead of calcium stearate.

The results were as shown in Table 1.

(Example 3) The same procedure as in Example 1 was carried out except that zinc 2-ethylhexanoate was supplied and added at a rate of 0.5 g/hour instead of calcium stearate.

The results were as shown in Table 1.

(Example 4) The same procedure as in Example 1 was conducted except that calcium dodecylbenzenesulfonate was supplied and added at a rate of 1.2 g/hour instead of calcium stearate.

The results were as shown in Table 1.

(Example 5) Instead of supplying and adding zinc 2-ethyl xanoate after the flash separation operation of the polymer solution in Example 3, it was added after the catalyst was inactivated by adding isopropyl alcohol and The same procedure as in Example 3 was carried out except that it was supplied and added before the flash separation operation of the polymer solution.

The results were as shown in Table 1.

(Comparative Example 1) The same procedure as in Example 1 was carried out except that calcium stearate was not used.

The results were as shown in Table 1.

(Comparative Example 2) The same procedure as in Example 1 was carried out except that isopropyl alcohol and calcium stearate were not used.

The results were as shown in Table 1.

(Comparative Example 3) Without using calcium stearate and in place of isopropyl alcohol, 0.5% of zinc 2-ethylhexanoate was used.
The same procedure as in Example 1 was carried out except that the mixture was supplied and added at a rate of g/hour.

The results were as shown in Table 1.

(This page, blank space below) As is clear from Table 1, when at least one compound selected from the group consisting of fatty acid metal salts, fatty acid esters, and sulfonic acid metal salts was not used (Comparative Example 1) and When the above compound and alcohol as a catalyst deactivator were not used (Comparative Example 2), the particle size of the catalyst residue was large, the number of gels in the film was large, and the screen mesh in the extruder was clogged. Furthermore, when a fatty acid metal salt is used instead of alcohol as a catalyst deactivator and the above compound is not used (Comparative Example 3), the reaction product with the catalyst remains in the copolymer and bleeds onto the film surface. As a result, the heat sheet strength of the film is significantly reduced.

In contrast, using alcohol as a catalyst deactivator,
and the method of the present invention using the above compound (Examples 1 to 5)
In this case, the particle size of the catalyst residue is small.

The number of gels in the film and the screen mesh clogging due to extrusion residue are also low.

[Effects of the invention] According to the method of the invention, there is no deterioration in heat sealability,
It is possible to produce an ethylene copolymer that is less likely to clog the screen mesh in an extruder and less likely to cause gel or fish eyes in the product.

Claims (2)

[Claims] (1) Using a catalyst obtained from a magnesium compound, a titanium compound, and an organoaluminum compound, ethylene or ethylene and an α-olefin having 3 to 18 carbon atoms were polymerized under conditions such that the resulting polymer was dissolved in the reaction medium. After that, add an alcohol having 1 to 4 carbon atoms to inactivate the catalyst, and then add at least one compound selected from the group consisting of fatty acid metal salts, fatty acid esters, and sulfonic acid metal salts. A method for producing an ethylene polymer characterized by: (2) The amount of at least one compound selected from the group consisting of fatty acid metal salts, fatty acid esters, and sulfonic acid metal salts per mole of aluminum as a catalyst component,
The method for producing an ethylene polymer according to claim 1, wherein the amount is 0.05 to 1.0 mol.