JPS6034961B2 - Manufacturing method for high-density ethylene polymer - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing high-density ethylene polymers.

More specifically, the present invention relates to a method for producing a high-density ethylene polymer that can produce a high-density ethylene polymer with few fish eyes in a high yield with high polymerization efficiency using a high-temperature melt polymerization method. When polymerizing or copolymerizing ethylene or ethylene and other Q-olefins (hereinafter simply referred to as polymerization) using a Ziegler type catalyst, the polymerization is carried out under conditions such that the polymer dissolves in the polymerization solvent at high temperatures. A high-temperature solution polymerization method is known.

In this method, it is desirable to increase the polymer concentration in order to increase the production capacity per polymerization vessel, but by adopting such high concentration polymerization conditions, the solution viscosity of the polymerization system increases, so it is difficult to carry out high concentration polymerization. There are limits to the conditions.

In particular, when producing high-molecular weight polymers, the increase in solution viscosity of the polymerization system is more significant, forcing the polymerization to be carried out under low concentration conditions, resulting in poor polymerization vessel efficiency. There are disadvantages in industrial implementation.
At this time, although it is possible to lower the solution viscosity by increasing the polymerization temperature, the catalytic activity often decreases significantly, although the degree varies depending on the catalyst system. Additionally, when typical aliphatic hydrocarbons are used as polymerization solvents, two phases are formed during possible variations in polymerization conditions: a polymer-rich solution phase and a polymer-dilute solution phase. In this case, it has been found that the obtained polymer is inhomogeneous and has the disadvantage that many fish eyes are formed when it is formed into a film or the like.
In particular, in the production of ethylene polymers in the high density region,
There are many problems of quality deterioration due to such two-phase formation.
The present inventors have solved the above-mentioned problems in the production of ethylene polymers, especially in the high-density region, all at once, increased the production capacity per polymerization vessel, and/or achieved high polymerization activity per unit catalyst. We conducted research to provide a method for manufacturing high-density ethylene polymer in small amounts with industrially satisfactory quality reproducibility.

As a result, it has been found that the above-mentioned improvement objective can be achieved by selecting a specific combination of catalysts and specific polymerization conditions as described below, and combining these conditions. That is, according to the present invention, the following (1) and (B), namely, a highly active titanium catalyst component whose essential components are magnesium, titanium, and halogen, which are formed by reacting a magnesium compound and a titanium compound;
and 5.) A mixed component consisting of a trialkylaluminum and an organoaluminum halogen compound, the average composition of which has at least one hydrocarbon group, and whose halide aluminum (atomic ratio) exceeds 0 and is 1.5. In the presence of a catalyst comprising an organoaluminum compound catalyst component that is less than
) is about 40 to about 150 qC, and the concentration of the polymer or copolymer in the hydrocarbon solvent is about 80 to about 40 qC.
Ethylene or ethylene and Q-olefin are continuously polymerized or copolymerized in a solvent of 0.0% and under conditions where the polymerization or copolymerization reaction system forms a homogeneous liquid phase to obtain a density of 0.940 mm/kg. Forming an ethylene polymer or copolymer with an intrinsic viscosity (in decalin, at 135°C) of 0.5 or more, preferably by adjusting the amounts of ethylene, Q-olefin and hydrogen used, It has been discovered that by forming ethylene polymers or copolymers of high density and intrinsic viscosity, the aforementioned technical challenges can be overcome at once.

Accordingly, an object of the present invention is to provide a method for producing high-density ethylene polymers that overcomes the above-mentioned problems.

The above objects and many other objects and advantages of the present invention will become more apparent from the following description. The highly active titanium catalyst component used in the present invention is a titanium catalyst component activated by a magnesium compound, and contains at least magnesium, titanium, and halogen as essential components.

Preferably, about 50 ethylene polymer per 1 o titanium
It is a catalyst component that has the ability to produce more than Generally, the catalyst component is in a solid state, but it may be one in which a magnesium compound, a solubilizer, and a titanium compound are dissolved in a hydrocarbon or the like. Titanium in catalyst component (1) is usually tetravalent and/or trivalent. The solid catalyst component preferably has a titanium content of from about 0.2 to about 1
Base weight %, more preferably about 0.3 to about 15 weight %
and the halide titanium (molar ratio) is preferably about 4 to about 30 u, more preferably about 5 to about 20 u.
It is 0. Furthermore, its specific surface area is preferably about 10〆'
more preferably from about 20 to about 1,000 per hour, and even more preferably from about 40 to about 900 per hour.
Such a solid highly active titanium catalyst component is widely known, and basically, a reactant with a large specific surface area is obtained by reacting a magnesium compound and a titanium compound, or a magnesium compound with a large specific surface area is obtained. A method in which titanium compounds are reacted is often used.

For example, co-pulverization of a magnesium compound and a titanium compound, thermal reaction of a magnesium compound with a sufficiently large specific surface area and a titanium compound, thermal reaction of an oxygen-containing magnesium compound and a titanium compound, and treatment with an electron donor. Typical examples include a method in which a magnesium compound is treated in advance with an organoaluminum compound or a halogen-containing silicon compound, or is reacted with a titanium compound without treatment. As described above, the highly active titanium catalyst component used in the present invention is a titanium catalyst component whose essential components are magnesium, titanium, and halogen, which are formed by reacting a magnesium compound and a titanium compound. Therefore, if at least one of the magnesium compound and the titanium compound is a halogen-containing compound, the treatment with a halogen compound such as the treatment with a halogen-containing silicon compound in the above example may or may not be performed. When both compounds do not contain halogen, or when it is desired to increase the halogen content, treatment with a halogen compound can be performed to form a desired titanium catalyst component containing magnesium, titanium, and halogen as essential components. Magnesium compounds used in the production of solid highly active titanium catalyst components include, for example, magnesium chloride, magnesium bromide, magnesium iodide, magnesium fluoride, magnesium hydroxide, magnesium oxide, magnesium hydroxyhalide, alkoxymagnesium, alkoxy Examples include magnesium halide, allyloxymagnesium, allyloxymagnesium halide, alkylmagnesium halide, and mixtures thereof.

These may be made by any manufacturing method.
The magnesium compound may also contain other metals, electron donors, and the like. Ti (CR
)4-m×m (R is a hydrocarbon group, × is a halogen, 0≦m
A tetravalent titanium compound represented by ≦4) can be exemplified.

Examples of such titanium compounds include TIC14, Ti
Br4, Ti (OC 2 days 5) CI3, Ti (OC 2 days 5
)2CI2, Ti(OC6&)3CI, Ti(OC2day5)4, and the like. Further examples include various titanium trihalides, such as titanium trichloride, obtained by reducing titanium tetrahalide with a reducing agent such as aluminum, titanium, hydrogen, or an organoaluminium compound. These titanium compounds can be used in combination of two or more types. Typical methods for obtaining such highly active titanium catalyst components include, for example, Japanese Patent Publication No. 46-134092, Japanese Patent Publication No. 46-134094, Japanese Patent Publication No. 46-134098, and Japanese Patent Publication No. 46-134098.
7-41676, Special Publication No. 47-46269 Special Publication No. 1977-
It is described in 3270 Special Publication No. 53-1796, etc.
It can be used in the present invention.

In the present invention, a catalyst comprising a highly active titanium catalyst component as described above and an organoaluminum catalyst component shown below (B) is used.

(B,) The catalyst component is a mixture consisting of a trialkylaluminum and an organoaluminium halide compound,
The average composition thereof has at least one hydrocarbon group, and c.

It is an organic aluminum compound catalyst component having a gennoaluminum (atomic ratio) of more than 0 and less than 1.5. Such an organoaluminum compound catalyst component does not have to be a mixed component consisting of one kind of trialkylaluminum and one kind of organoaluminum halogen compound, but can be two or more kinds of them, respectively. It is sufficient that the halogen aluminum (atomic ratio) in the average composition satisfies the above range. As such an organoaluminum compound catalyst component (B), for example, the formula R-N
<OR2)nHpfu (here, RI and R2 are hydrocarbon groups, X is a halogen atom, m is a positive number of Ism<3, and n is OS
nSI is a positive number, p is a positive number of 0≦p<2, q is 0<q×1
．． It is a positive number of 5, and m+n+P+q=3.

) A mixed component consisting of a trialkylaluminum and an organoaluminum halogen compound having an average composition represented by the following can be exemplified.

Specifically, the general formula R is also AI(CR2)n (here R
1, R2 and X are the same as above.

m is Ism<3, 0≦n≦1・q is ○〈q<1-5, m
+n+q=3) A mixed component consisting of a trialkylaluminum and an organoaluminum halogen compound and a general formula R are also AI (where RI and X are the same as above, and m is 1.5<m<3). , q is 0<q
<1.5, m+q=3), general formula R 玲NHPXq (where RI and X are the same as above, m is ・mi m<3, p is ○
≦p<2, q is ○<q<1. Examples include a mixed component consisting of a trialkylaluminum and an organoaluminum halogen compound having an average composition represented by im+p+q; 3). Furthermore, it may be a mixture of two or more types of lagoon ingredients having the above-mentioned average composition.

In the present invention, the catalyst component (B,) is used in the form of a mixture consisting of trialkylaluminium and organoaluminum halogen compound as exemplified above. Examples of organoaluminum compounds used to form a mixed component consisting of trialkylaluminum and organoaluminium halide compounds include trialkylaluminum such as triethylaluminum, tri-n-butylaluminum, and triisobutylaluminum; diethylaluminum chloride; Dialkylaluminum halogenides such as dibutylaluminum chloride, diethylaluminium bromide; alkylaluminum sesquihalogenides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesquibromide, ethylaluminum dichloride, propylaluminum dichloride, butylaluminum dibromide partially alkoxylated and halogenated alkyl aluminums such as ethyl aluminum ethoxy chloride, butyl aluminum butoxy chloride, ethyl aluminum ethoxy bromide; From these, one or more types of trialkylaluminum and organoaluminum halogen compounds may be selected and used in combination so as to have an average composition represented by the above formula. In the above formula, RI and R2 are the same or different aliphatic, alicyclic or aromatic hydrocarbon groups, preferably,
The carbon content is 1 and 1, and aliphatic ones are particularly suitable. Further, X is a halogen such as chlorine, bromine, iodine, or fluorine, and chlorine is particularly preferred. Also, q is 0<q
<1.5, preferably 0.1≦q≦1.
In the component (B,), as the ratio of halogen to aluminum deviates from the above range, the activity decreases, which is not preferable.

In the present invention, the polymerization solvent is an alicyclic hydrocarbon having a boiling point (at 76 mHg) of about 4000 to about 150 qo, particularly preferably about 4000 to 105 qo, or a carbonized alicyclic hydrocarbon containing about 15% by volume or more of the same. Hydrogen solvents such as mixtures of cycloaliphatic and aliphatic hydrocarbons can be used.

Examples of alicyclic hydrocarbons used for this purpose include cyclobentane, methylcyclobentane, cyclohexane, methylcyclohexane, and cyclooctane. In addition, aliphatic hydrocarbons that can be used together with alicyclic hydrocarbons include those with a boiling point (at 76 mHg) of about 250 to about 150, particularly about 25 to about 105q.
o or less is preferable. Examples of such aliphatic hydrocarbons include isobentane, n-bentane, isohexane, n-hexane, n-heptane, and n-octane. When using a mixture of alicyclic hydrocarbons and aliphatic hydrocarbons, the alicyclic hydrocarbons are about 1
It is preferable to use the mixture at a mixing ratio such that the string capacity is at least 2%, preferably about 2% or more, and particularly preferably about 4% or more. In the present invention, by using the above-mentioned solvent, it is possible to maintain uniformity even if the polymer concentration is increased in a high temperature region, so there is an advantage that the polymer production capacity per polymerization vessel can be increased. Furthermore, there is the advantage that a high quality polymer free of fish eyes can be obtained. The polymerization temperature is from about 150 to about 300 qo, preferably from about 160 to about 250 qo, and the polymerization pressure is from about 3 to about 100 k9'-G, preferably from about 10 to about 50 k9/carp-G.

The concentration of the polymer in the hydrocarbon solvent is from about 80 to about 400 g/s, preferably from about 120 to about 300 g/s. In the present invention, a polymer of good quality can be produced without any trouble even under conditions where the polymer concentration exceeds 200 m/s. The polymer concentration is also selected to provide conditions for the polymer system to form a homogeneous liquid phase. If the polymerization conditions are selected such that the polymerization liquid undergoes phase separation to form two phases,
The resulting polymer is heterogeneous and exhibits many fish eyes when formed into a film. The presence or absence of phase separation depends on various polymerization conditions such as polymerization temperature and polymerization pressure as well as the composition of the polymerization solvent, so it is recommended to select the phase separation appropriately so as not to cause phase separation. In general, polyethylene dissolved in a hydrocarbon solvent has a transparent homogeneous region, a region that completely separates into a dense layer and a dilute layer, and a cloudy metastable region that is an intermediate state between the two, depending on the polymer concentration and temperature. Polymerization in the region where phase separation occurs or in the cloudy region causes frequent occurrence of fish eyes.

The precipitation point, which is the boundary point between the region where a stable homogeneous phase is formed and the phase separation or cloudy region, is influenced by the polymer concentration. ) becomes higher, and the lower the polymerization pressure, the higher the precipitation point temperature.

In addition, aliphatic hydrocarbons with lower boiling points have lower precipitation points as solvents, and as the proportion of aliphatic hydrocarbons increases, the precipitation point temperature tends to increase, specifically at 1509/its concentration. = 2.40, density 0.960 ta' The precipitation point of that polyethylene in n-hexane is 11 at a pressure of 25k9/m
3 qo, whereas in a solvent of cyclohexane/n-hexane = 50/50, it is 200 qo or more. Such precipitation points can be easily determined experimentally by beaker scale experiments. According to the method of the present invention,
As mentioned above, at a temperature of about 150 to about 30,000 and a pressure of about 3 to about 100 k9/g, at least about The concentration of polymer or copolymer in the hydrocarbon solvent is about 80 to about 40% by volume.
Ethylene or ethylene and Q-olefin are continuously polymerized or copolymerized under conditions where the polymerization or copolymerization reaction system forms a homogeneous liquid phase, and the density is 0.
．． More than 940 evenings/earth, preferably density 0.945 evenings/earth
Exceeds mass and has an intrinsic viscosity (in Decalin, at 1350) of 0
．． Forms an ethylene polymer or copolymer of 5d'/f or more, preferably 0.8/f or more. The density of the polymer can be adjusted, in addition to various polymerization conditions, by the mutual ratio of ethylene and other Q-olefins copolymerized therewith.

For example, although it varies depending on the polymerization conditions, the supply ratio (mole ratio) of ethylene and Q-olefin is set to loo/0 to 10.
It is better to set it to 0/30. Q-olefins that can be copolymerized with ethylene include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-bentene, 1-octene, 1-decene, 1-dodecene,
Q-olefins having 3 to 18 carbon atoms such as -tetradecene and 1-octadecene are preferred. The intrinsic viscosity of the polymer is preferably controlled by the coexistence of hydrogen. In order to obtain a product with the above-mentioned intrinsic viscosity, the amount of hydrogen used relative to ethylene should be adjusted depending on the polymerization conditions.
The molar ratio is preferably about 1/4 to about 1/10,000. The polymerization according to the invention is carried out continuously.

For example, polymerization solvent, catalyst, ethylene or ethylene and Q-
A method is adopted in which the olefin and, in some cases, hydrogen, etc. are continuously supplied to the polymerization vessel, while the polymerization solution is continuously discharged and taken out from the polymerization vessel. By doing so, the polymerization conditions can be kept constant and a homogeneous polymer can be obtained. Of course, it is also possible to perform multistage polymerization under different polymerization conditions using two or more consecutive polymerization vessels for the purpose of adjusting the molecular weight distribution of the polymer, but in this case as well, continuous polymerization can be performed. be exposed. Each catalyst component should be about 0.0005 to about 1 mmol per liquid phase in terms of titanium atoms, particularly about 0.001 to about 0.
．． Also, (B,), (B
,) is preferably provided such that the titanium (atomic ratio) in the aluminum/wind component is from about 5 to about 200, particularly from about 10 to about 500.

Conventionally known methods can be used to recover the polymer from the polymer solution discharged from the polymerization vessel.

The polymer thus obtained can often be used without decatalyzing. According to the present invention, the yield of polymer per catalyst is large and it is possible to produce a large amount of polymer per polymerization vessel.

Moreover, the quality of the obtained polymer is very excellent. Next, an example will be explained.

Example 1 <Catalyst> 10 mol of commercially available anhydrous magnesium chloride was suspended in 50 mol of dehydrated hexane in a nitrogen stream, 40 mol of ethanol was added dropwise over 1 hour while stirring, and then 1 mol of commercially available anhydrous magnesium chloride was added dropwise at room temperature. Time reacted.

To this, 20 mol of diethyl aluminum chloride was added dropwise at room temperature, and the mixture was lit for 1 hour. Next, titanium tetrachloride 10
After adding the mol, the reaction was carried out at 50 qo for 2 hours under lighting. The generated solid portion is separated and collected by face fishing, and after repeated washing with purified hexane, it is made into a suspension of hexane. The concentration of titanium was determined by titration. Polymerization> 200 Using the continuous polymerization reactor, the dehydrated purified solvent methylcyclobentane was used for 100 hours, triethylaluminum 200 mol/hr, diethylaluminum chloride 20 mmol/hr, and the supported catalyst was converted into titanium atoms. At the same time, 25 kg of ethylene was fed into the polymerization vessel at a rate of 0.65 mol/hr.
'hr, hydrogen is continuously supplied at a rate of 200 evenings/hr,
Ethylene polymerization was carried out under the following conditions: a polymerization temperature of 200 oo, a total pressure of -G of 30 kg', a residence time of 1 hour, and a polymer concentration of 225/so with respect to the solvent methylcyclobentane.

The resulting polyethylene had a density of 0.967 mm/base, an intrinsic viscosity of 1.74 mm, and a melt index of 2.35. When continuous polymerization was carried out under the above conditions, the inside of the reactor was observed through a peephole, and the solution containing polyethylene was a colorless and transparent homogeneous solution, and the condition was very good. In addition, the polymerization activity of the catalyst is 34 per mol of Til.
600 turbo remer, the catalyst component remaining in the polymer was Til. The content was 3 ppm and the CI was 44 ppm, which were extremely low levels that did not require removal of the catalyst at all. Furthermore, when the obtained polyethylene was formed into a film, it became clear that a very good polyethylene with almost no fish eyes was obtained. Comparative Example 1 Same as Example 1, except that n-hexane was used instead of the solvent methylcyclobentane in the polymerization method of Example 1, and n-hexane was supplied at a rate of 100 mmol/hr, triethylaluminum 20 mmol/hr, and diethyl aluminum. mol'hr of aluminum chloride 20, 0.6 mol/hr in terms of titanium atoms of the supported catalyst obtained by the method of Example 1
Ethylene is continuously supplied at a ratio of 22
kg'hr, hydrogen was continuously supplied at a rate of 200 so'hr, and polymerization was carried out at a polymerization temperature of 200q0, a total pressure of 30k9/uniform G, and a residence time of 1 hour.

The polymer concentration relative to the solvent n-hexane was 183 t/t. Therefore, the polymerization activity is 3050 per mol of Til.
Corresponds to 0 saws. The obtained polyethylene has a density of 0.
It had an intrinsic viscosity of 966 m/m, an intrinsic viscosity of 1.79 m/m, and a melt index of 2.10. The solution containing polyethylene in the polymerization reactor under the above conditions undergoes phase separation, and the part with a high concentration of polyethylene and the solution with a very dilute polyethylene concentration are separated as if they were flowing through a mixed system of water and oil. It was a cloudy, heterogeneous solution as shown in Example 1.
A colorless and transparent homogeneous solution was not obtained as shown in the figure, and the concentration was not sufficiently satisfactory. Since the polymerization activity of the polyethylene obtained by the above method was only slightly lower than that of Example 1, the catalyst component remaining in the polymer was Til. 6 ppm, CI 57 ppm, and no need to remove the catalyst at all. However, when the obtained polyethylene was formed into a film, it became clear that fish eyes occurred frequently and the polyethylene had no commercial value. Comparative Example 2 In the polymerization method of Example 1, the solvent methylcyclobentane was used for 100 hours, and triethylaluminum was added for 30 mm.
The supported catalyst obtained by the method of Example 1 was continuously fed at a rate of 3.0 mol/hr in terms of titanium atoms, and 21 k9/hr of ethylene and 150 mol/hr of hydrogen were added to the polymerization vessel. 'hr', and the polymerization temperature was 2.
Polymerization was carried out at a total pressure of 30 k9/G and a residence time of 1 hour.

Polymer concentration relative to solvent methylcyclobentane is 197
It was evening. The obtained polyethylene has a density of 0.96
The melt index was 3.49, and the intrinsic viscosity was 1.62. The solution containing polyethylene in the polymerization reactor under the above conditions was a colorless and transparent homogeneous solution as in Example 1, and the condition of the solution was very good. However, the polymerization activity of the catalyst was 67 per Tilmmol.
The amount of the catalyst component remaining in the polymer was about 5 times that of Example 1. For this reason, when the obtained polyethylene was formed into a film, foaming due to decomposition of the catalyst residue was observed, and the surface of the film became rough. Example 2 In the polymerization method of Example 1, a solvent containing methylcyclobentane and n-hexane in a ratio of 3:7 was added to 1
00〆'hr, triethylaluminum 20mmol/
hr, ethylaluminum sesquichloride 20 mol
'hr, the carrier obtained by the method of Example 1 was continuously supplied with the catalyst at a rate of 0.25 mmol/hr in terms of titanium atoms, and 18 kg'hr of ethylene and 3 hr of hydrogen were added to the polymerization vessel.
Continuously supplied at a rate of 0.000 m/hr, polymerization temperature of 160 m/hr.
Ethylene polymerization was carried out under the following conditions: °C, total pressure 25 k9/uniform G, residence time 1 hour, and polymer concentration to solvent 152 k/g.

The obtained polyethylene had a density of 0.969/Sakaki, an intrinsic viscosity of 1.44/Sakaki, and a melt index of 6.0. When continuous polymerization was carried out under the above conditions, the polyethylene-containing solution in the reactor became a colorless and transparent homogeneous solution, and the condition of the polymer was very good.

In addition, the polymerization activity of the catalyst is equivalent to 6 female 00 turbo remer per mol of Til, and the catalyst component remaining in the polymer is T
il ppm or less, and CI was 25 ppm, which was a very low level that did not require removal of the catalyst at all. Furthermore, when the obtained polyethylene was formed into a film, it became clear that a very good polyethylene with almost no fish eyes was obtained. Comparative Example 3 In the polymerization method of Example 1, methylcyclobentane and n
- Solvent containing hexane in a ratio of 5:95 at 100 evenings/h
r, triethylaluminum 20 mmol/hr, the carrier obtained by the method of Example 1 has a catalyst content of 0 in terms of titanium atoms.
．． Continuously supplied at a rate of 60 mmol'hr, and ethylene 18k9/hr and hydrogen 250 mmol/hr into the polymerization vessel.
The polymerization temperature was 160 qC, and the total pressure was 2.
Polymerization was carried out using 5k9/di-G and a residence time of 1 hour.

Polyethylene was obtained at a polymer concentration to solvent ratio of 151/l. The density of the obtained polyethylene is 0.9
It had an intrinsic viscosity of 1.43 d'' and a melt index of 6.1. Compared with Example 3, the polymerization activity decreased to 25,200 turbo remers per mol of Til skin, about 1'2.5, and during continuous polymerization, the solution containing polyethylene in the reactor became cloudy, and the solution containing polymer became cloudy. A phenomenon of separation into two layers, a dense layer and a dilute layer, occurred. Furthermore, when the obtained polyethylene was formed into a film, many fish eyes were observed. Comparative Example 4 In the method of Example 1, a highly active titanium catalyst component was similarly prepared, and in the polymerization method, 100 mmol/hr of dehydrated methylcyclobentane was supplied as a polymerization solvent, and 20 mmol/hr of triethylaluminum and 20 mmol of diethylaluminum chloride were added. 'hr, 30 mmol/hr of diethylaluminium chloride was supplied, and the highly active titanium catalyst component prepared in Example 1 was continuously supplied at a rate of 2.44 mol/hr in terms of titanium atoms. , and 21k9/hr of ethylene and 20% of hydrogen in the polymerization vessel.
Continuously supplied at a rate of 0/hr, polymerization temperature 200°C
The polymerization of ethylene was carried out under the following conditions: total pressure of 30 k9'G, residence time of 1 hour, and polymer concentration of 176 k9' with respect to the solvent methylcyclobentane.

Claims (1)

[Claims] 1 The following (A) and (B_1), namely (A) a highly active titanium catalyst component containing magnesium, titanium, and halogen as essential components formed by reacting a magnesium compound and a titanium compound, and (B) A mixed component consisting of a trialkylaluminium and an organoaluminum halogen compound, the average composition of which has at least one hydrocarbon group, and whose halogen/aluminum (atomic ratio) is greater than 0 and less than 1.5. In the presence of a catalyst comprising an organoaluminum compound catalyst component, at a temperature of about 150 to about 300°C and a pressure of about 3 to about 100 kg/
In a hydrocarbon solvent containing at least about 15% by volume of alicyclic carbon having a boiling point (760 mmHg) of about 40 to 150 °C in cm^2 gauge, polymer or copolymerization in the hydrocarbon solvent. Ethylene or ethylene and α-olefin at a concentration of about 80 to about 400 g/l solvent and under conditions where the polymerization or copolymerization reaction system forms a homogeneous liquid phase,
Continuously polymerized or copolymerized to a density of 0.940g
/cm^3 and the intrinsic viscosity (in Decalin, 135
C) 0.5 dl/g or more of an ethylene polymer or copolymer.