JPH07118173A - Alpha-olefin oligomer composition - Google Patents

Abstract

PURPOSE:To provide an alpha-olefin oligomer composition obtained by the oligemerization reaction of an alpha-olefin, richin polymers having carbon number of 4-8 and, accordingly, giving little load on fractional process and advantageously usable as various kinds of industrial raw materials. CONSTITUTION:This alpha-olefin oligomer composition is produced by the oligomerization reaction of an alpha-olefin and contains >=90wt.% of polymers containing 4-8 carbon atoms and <=10wt.% of polymers having carbon number of >=10. Preferably, the composition contains >=90wt.% of 1-hexene.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an α-olefin low polymer composition, and more particularly, to a reaction product composition obtained by a low polymerization reaction of α-olefin, which comprises 4 to 8 The present invention relates to an α-olefin low polymer composition which is rich in a polymer having a carbon number, and therefore has a small load in the fractionation step, and which can be industrially advantageously used for various raw materials.

[0002]

2. Description of the Related Art Conventionally, α-olefin low polymers useful as various raw materials have been obtained by low polymerization reaction of α-olefin. For example, a low-polymerization reaction of ethylene gives an α-olefin low-polymer composition containing 1-hexene. Then, 1-hexene recovered from such an α-olefin low polymer composition by distillation is used as a raw material monomer of a useful polymer such as linear low density polyethylene (L-LDPE).

Further, 1-butene and butane having 4 carbon atoms and 1 octene and octane having 8 carbon atoms can be converted into sulfonic acids by, for example, adding hydrogen sulfide and then oxidizing. Salts are useful as surfactants. In particular, 1-hexene is in increasing demand as a raw material monomer for polymers. Therefore, as a reaction product composition obtained by a low polymerization reaction of α-olefin, a composition having a content of a polymer having 4 to 8 carbon atoms of 90% by weight or more has great industrial utility value. In particular, the industrial value of the composition having a 1-hexene content of 90% by weight is remarkable.

On the other hand, as a low polymerization method of α-olefin such as ethylene, there is known a method of using a chromium-based catalyst comprising a combination of a specific chromium compound and a specific organic aluminum compound. For example, Japanese Patent Publication No. Sho 43-1870
No. 7 discloses a V represented by the general formula MXn and containing chromium.
A process for obtaining 1-hexene from ethylene with a catalyst system consisting of a Group IA transition metal compound (M) and polyhydrocarbyl aluminum oxide (X) is described.

Further, in JP-A-3-128904, α-olefin is trimerized using a catalyst obtained by previously reacting a chromium-containing compound having a chromium-pyrrolyl bond with a metal alkyl or Lewis acid. How to do is described.

However, the reaction product composition obtained by a conventionally known method contains a polymer having a carbon number of 4 to 8 in an amount of 75% by weight or less, and additionally contains a polymer having various carbon numbers. is doing. For example, when a polymer having a carbon number of 4 is represented by the symbol "C4", an example of a typical composition confirmed by the additional test by the present inventor is C4: 1.
9%, C6: 40%, C8: 16%, C10: 13%,
C12: 7%, C14: 3%, C16: 1%, C18:
1%. Incidentally, most of the respective polymers are α-olefins.

[0007]

However, in the case of the reaction product composition as described above, since the boiling points are close to each other, a large number of constituent components which are difficult to separate from each other are contained.
Since the content of the polymer having 8 to 8 carbon atoms is small, not only the fractionation operation is difficult but also the burden of the fractionation step is large.

The present invention has been made in view of the above circumstances, and an object thereof is a reaction product composition obtained by a low polymerization reaction of α-olefin, which is a polymer having 4 to 8 carbon atoms. Therefore, since the load on the fractionation step is small, it can be industrially advantageously used for various raw materials.
-To provide an olefin low polymer composition.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and as a result, by using a specific chromium-based catalyst, a low polymerization reaction of α-olefin, particularly ethylene It was found that a low polymerization reaction mainly composed of trimerization proceeds selectively to obtain a novel reaction product composition rich in a polymer having 4 to 8 carbon atoms.

The present invention has been completed based on the above findings, and the gist thereof is a reaction product composition obtained by a low polymerization reaction of α-olefin, which has 4 to 8 carbon atoms. The content of the polymer has 90% by weight or more and 10
The α-olefin low polymer composition is characterized in that the content of the polymer having the above carbon number is 10% by weight or less.

The present invention will be described in detail below. First, a method for producing the α-olefin low polymer composition of the present invention will be described. The α-olefin low polymer composition of the present invention is a reaction product composition obtained by a low polymerization reaction of α-olefin. Then, the low polymerization reaction of α-olefin can be carried out, for example, using a catalyst system comprising at least a combination of a chromium compound and an amine or a metal amide and an alkylaluminum compound.

The chromium compound is represented by the general formula CrXn. However, in the general formula, X represents an arbitrary organic group or inorganic group or a negative atom, n represents an integer of 1 to 6, and when n is 2 or more, X may be the same or different from each other. Good. The valence of chromium is 0 to 6, and n in the above formula is preferably 2 or more.

Examples of the organic group include various groups having usually 1 to 30 carbon atoms. Specific examples thereof include a hydrocarbon group, a carbonyl group, an alkoxy group, a carboxyl group, a β-diketonate group, a β-ketocarboxyl group, a β-ketoester group and an amide group. Examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, an aryl group, an alkylaryl group and an aralkyl group. Examples of the inorganic group include a chromium salt-forming group such as a nitrate group and a sulfate group, and examples of the negative atom include oxygen and halogen.

The preferred chromium compound is an alkoxy salt of chromium, a carboxyl salt, a β-diketonate salt, a salt of β-ketoester with an anion, or a chromium halide, specifically, chromium (IV) tert-butoxide. , Chromium (III) acetylacetonate, chromium (III)
Trifluoroacetylacetonate, chromium (III) Hexafluoroacetylacetonate, chromium (III) (2
2,6,6-tetramethyl-3,5-heptanedionate), Cr (PhCOCHCOPh) ₃ (provided that P is
h represents a phenyl group. ), Chromium (II) acetate, chromium (III) acetate, chromium (III) 2-ethylhexanoate, chromium (III) benzoate, chromium (III) naphthenate, Cr (CH ₃ COCHCOOCH ₃ ) ₃ , chromium (III) chloride , Chromium chloride, chromium bromide, chromium bromide, chromium iodide, chromium iodide, chromium fluoride, chromium fluoride and the like.

Further, a complex composed of the above-mentioned chromium compound and an electron donor can also be preferably used. The electron donor is selected from compounds containing nitrogen, oxygen, phosphorus or sulfur.

Examples of the nitrogen-containing compound include nitriles, amines, amides, and the like. Specifically, acetonitrile, pyridine, dimethylpyridine, dimethylformamide, N-methylformamide, aniline, nitrobenzene, tetramethylethylenediamine, diethylamine,
Examples include isopropylamine, hexamethyldisilazane, and pyrrolidone.

Examples of oxygen-containing compounds include esters, ethers, ketones, alcohols, aldehydes,
Specific examples include ethyl acetate, methyl acetate, tetrahydrofuran, dioxane, diethyl ether, dimethoxyethane, diglyme, triglyme, acetone, methyl ethyl ketone, methanol, ethanol, acetaldehyde and the like.

Examples of phosphorus-containing compounds include hexamethylphosphamide, hexamethylphosphorus triamide, triethylphosphite, tributylphosphine oxide, triethylphosphine and the like. On the other hand, examples of the sulfur-containing compound include carbon disulfide, dimethyl sulfoxide, tetramethylene sulfone, thiophene and dimethyl sulfide.

Therefore, as an example of a complex composed of a chromium compound and an electron donor, a chromium halide ether complex,
Ester complex, ketone complex, aldehyde complex, alcohol complex, amine complex, nitrile complex, phosphine complex,
Examples thereof include thioether complexes. Specifically, Cr
Cl ₃ / 3THF, CrCl ₃ / 3dioxane, C
_{rCl 3 · (CH 3 CO 2} n-C 4 H 9), CrCl 3
_{· (CH 3 CO 2 C 2} H 5), CrCl 3 · 3 (i-C
₃ H ₇ OH), CrCl ₃ · 3 [CH ₃ (CH ₂ ) ₃ C
H (C ₂ H ₅ ) CH ₂ OH], CrCl ₃ / 3pyri
_{dine, CrCl 3 · 2 (i} -C 3 H 7 NH 2),
[CrCl ₃ · 3CH ₃ CN] · CH ₃ CN, CrCl
_{3 · 3PPh 3, CrCl 2 ·} 2THF, CrCl 2 ·
2pyridine, CrCl ₂ · 2 [(C ₂ H ₅ ) ₂ N
H], CrCl ₂ · 2CH ₃ CN, CrCl ₂ · 2 [P
(CH ₃ ) ₂ Ph] and the like.

As the chromium compound, a compound soluble in a hydrocarbon solvent is preferable, and a β-diketonate salt of chromium,
Carboxylates, salts with anions of β-ketoesters, β
-Ketocarboxylic acid salts, amide complexes, carbonyl complexes, carbene complexes, various cyclopentadienyl complexes, alkyl complexes, phenyl complexes and the like. Examples of various carbonyl complexes of chromium, carbene complexes, cyclopentadienyl complexes, alkyl complexes, and phenyl complexes include Cr (CO) ₆ , (C ₆ H ₆ ) Cr (CO) ₃ ,
(CO) ₅ Cr (= CCH ₃ (OCH ₃ )), (CO)
₅ Cr (= CC ₆ H ₅ (OCH ₃ )), CpCrCl ₂
(Where Cp represents a cyclopentadienyl group), (
Cp * CrClCH ₃ ) ₂ (where Cp * represents a pentamethylcyclopentadienyl group), (CH ₃ ) ₂ CrC
1 and the like are exemplified.

The chromium compound can be used by supporting it on a carrier such as an inorganic oxide, but it is preferable to use it in combination with other catalyst components without supporting it on the carrier. That is, if a chromium-based catalyst is used in a specific contact mode according to a preferable low polymerization reaction of α-olefin described later, a high catalytic activity can be obtained without supporting a chromium compound on a carrier. When the chromium compound is used without being loaded on the carrier, the loading on the carrier which involves complicated operations can be omitted, and the total amount of the catalyst used (the total amount of the carrier and the catalyst component) is increased by the use of the carrier. It is possible to avoid the problem.

The amine used in the chromium-based catalyst is a primary or secondary amine. Examples of primary amines include ammonia, ethylamine, isopropylamine, cyclohexylamine, benzylamine, aniline, naphthylamine, and the like, and secondary amines include diethylamine, diisopropylamine, dicyclohexylamine,
Dibenzylamine, bis (trimethylsilyl) amine,
Morpholine, imidazole, indoline, indole,
Pyrrole, 2,5-dimethylpyrrole, 3,4-dimethylpyrrole, 3,4-dichloropyrrole, 2,3,4
Examples include 5-tetrachloropyrrole, 2-acylpyrrole, pyrazole, pyrrolidine and the like.

The metal amide used in the chromium-based catalyst is 1
A metal amide derived from a primary or secondary amine, specifically, a primary or secondary amine and a group IA, I
An amide obtained by reaction with a metal selected from Group IA, Group IIIB and Group IVB. Specific examples of such metal amides include lithium amide, sodium ethylamide, calcium diethylamide, lithium diisopropylamide, potassium benzylamide, sodium bis (trimethylsilyl) amide, lithium indolide, sodium pyrrolide, lithium pyrrolide and potassium. Examples thereof include pyrrolide, potassium pyrrolidide, aluminum diethylpyrrolide, ethylaluminum dipyrrolide and aluminum tripyrolide.

Of the above, secondary amines, metal amides derived from secondary amines, or mixtures thereof are preferably used. Particularly, as the secondary amine, pyrrole,
Examples of the metal amide derived from 2,5-dimethylpyrrole, 3,4-dimethylpyrrole, 3,4-dichloropyrrole, 2,3,4,5-tetrachloropyrrole, 2-acylpyrrole and a secondary amine , Aluminum pyrrolide, ethylaluminum dipyrrolide, aluminum tripyrolide, sodium pyrrolide, lithium pyrrolide, potassium pyrrolide are preferred. And
Among the pyrrole derivatives, those having a hydrocarbon group on the pyrrole ring are particularly preferable.

In the above chromium-based catalyst, the alkylaluminum compound represented by the following general formula (1) is preferably used as the alkylaluminum compound.

Embedded image R ¹ _m Al (OR ² ) _n H _p X _q (1)

In the formula, R ¹ and R ² usually have a carbon number of 1 to
15, preferably 1 to 8 hydrocarbon groups, which may be the same or different from each other, X represents a halogen atom, m is 0 <m ≦ 3, n is 0 ≦ n <3, p Is 0 ≦ p <
3 and q are numbers of 0 ≦ q <3, and
It represents a number that is m + n + p + q = 3.

Examples of the above alkylaluminum compound include trialkylaluminum compounds represented by the following general formula (2), halogenated alkylaluminum compounds represented by the general formula (3), and alkoxy groups represented by the general formula (4). Examples thereof include aluminum compounds and alkylaluminum hydride compounds represented by the general formula (5). The meanings of R ¹ , X and R ² in each formula are the same as above.

[0028]

Embedded image R ¹ ₃ Al (2) R ¹ _m AlX _3-m (m is 1.5 ≦ m <3) (3) R ¹ _m Al (OR ² ) _3-m ( m is 0 <m <3, preferably 1.5 ≦ m <3) (4) R ¹ _m AlH _3-m (5) (m is 0 <m <3, preferably 1. 5 ≦ m <3)

Specific examples of the alkylaluminum compound include trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum monochloride, diethylaluminum ethoxide, diethylaluminum hydride and the like. Among these, trialkylaluminums are particularly preferable in that the amount of polymer by-products is small.

The low polymerization reaction of α-olefin is carried out in a solvent using a catalyst system comprising the above catalyst components.
The amount of the chromium compound used is usually 0.1 × 10 ^{−3 to 5} g, preferably 1.0 × 10 ⁻³ to 2 per liter of the solvent.
The range is g. On the other hand, the amount of alkylaluminum compound used is usually 0.1 mm per 1 g of chromium compound.
It is at least ol but is preferably at least 5 mmol from the viewpoint of catalytic activity and trimer selectivity. And the upper limit is usually 50 mol. The amount of amine or metal amide used is usually 0.00 per 1 g of chromium compound.
It is 1 equivalent or more, preferably 0.005 to 1000 equivalents, and more preferably 0.01 to 100 equivalents.

The contact between the α-olefin and the chromium-based catalyst is preferably carried out in such a manner that the chromium compound and the alkylaluminum compound do not come into contact with each other in advance. According to such a contact mode, it is possible to selectively carry out the trimerization reaction and obtain 1-hexene from the raw material ethylene in a high yield.

The above-mentioned specific contact mode is specifically as follows.
When the amine is represented by “amine or metal amide”, (1) a method of introducing α-olefin and a chromium compound into a solution containing an amine and an alkylaluminum compound, and (2) α into a solution containing a chromium compound and an amine. -Method of introducing olefin and alkylaluminum compound (3) Method of introducing α-olefin, amine and alkylaluminum compound into a solution containing chromium compound, (4) α-olefin, chromium into solution containing an alkylaluminum compound It can be carried out by a method of introducing a compound and an amine, (5) a method of introducing each of a chromium compound, an amine, an alkylaluminum compound and α-olefin into a reactor simultaneously and independently. And each said solution is prepared using a reaction solvent.

In the above description, "a mode in which the chromium compound and the alkylaluminum compound do not come in contact with each other in advance" means not only at the start of the reaction but also after that, additional α-olefin and the catalyst component are supplied to the reactor. Also means that such a mode is maintained.

The reason why the activity of the low polymerization reaction of α-olefin becomes low when the chromium-based catalyst is used in such a manner that the chromium compound and the alkylaluminum compound are in contact with each other in advance is not clear, but it is presumed as follows. To be done.

That is, it is considered that when the chromium compound and the alkylaluminum are brought into contact with each other, the ligand exchange reaction proceeds between the ligand coordinated with the chromium compound and the alkyl group in the alkylaluminum compound. And, the alkyl-chromium compound produced by such a reaction is unstable in itself, unlike the alkyl-chromium compound produced by the usual method. Therefore, alkyl-
Decomposition / reduction reaction of the chromium compound preferentially progresses, and as a result, inappropriate demetallation is induced in the α-olefin low polymerization reaction, and the activity of the α-olefin low polymerization reaction is reduced.

As a raw material for the low polymerization reaction of α-olefin, a substituted or unsubstituted α-olefin having 2 to 30 carbon atoms is used. Specific examples include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 3-methyl-1-butene, 4-methyl-1-pentene and the like. In particular, ethylene is suitable as the starting material α-olefin, and 1-hexene, which is a trimer of ethylene, can be obtained from ethylene in high yield and high selectivity.

In the low polymerization reaction of α-olefin,
As the solvent, butane, pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane, linear or alicyclic saturated hydrocarbon such as decalin,
Aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, mesitylene, and tetralin, chain chlorinated hydrocarbons such as chloroform, carbon tetrachloride, methylene chloride, dichloroethane, trichloroethane, and tetrachloroethane, and chlorination of chlorobenzene and dichlorobenzene. Aromatic hydrocarbons and the like are used. These may be used alone or as a mixed solvent.

As the solvent, a linear saturated hydrocarbon having 4 to 7 carbon atoms or an alicyclic saturated hydrocarbon is particularly preferable. By using these solvents, it is possible to suppress the by-product of the polymer, and further, when the alicyclic hydrocarbon is used, there is an advantage that a high catalytic activity can be obtained.

The reaction temperature is preferably in the range of 0 to 70 ° C. On the other hand, the reaction pressure is from normal pressure to 250 kg / c.
It can be selected from the range of m ² , but usually 100 kg / c
A pressure of m ² is sufficient. And the residence time is usually 1
The range is from minutes to 20 hours, preferably 0.5 to 6 hours. The reaction system may be a batch system, a semi-batch system or a continuous system, and it is preferable to make hydrogen coexist during the reaction because improvement in catalytic activity and trimer selectivity is recognized.

The α-olefin low-polymer composition of the present invention is prepared by using the raw material α after the low-polymerization reaction of α-olefin as described above.
A reaction product composition obtained by removing olefins. The content of the polymer having 4 to 8 carbon atoms is 90% by weight or more and the content of the polymer having 10 or more carbon atoms is 10% by weight or less. In the preferred α-olefin polymer composition of the present invention,
A hexene content of 85% by weight or more.

In the more preferable α-olefin polymer composition of the present invention, the content of 1-hexene is 90% by weight or more. The content of each polymer having 12 or more carbon atoms is usually 1 to 2% by weight. Therefore, the α-olefin low polymer composition of the present invention is rich in useful polymers having a carbon number of 4 to 8 and has a small load in the fractionation step, and is industrially advantageously used for various raw materials. You can

The α-olefin low polymer composition of the present invention having a 1-hexene content of 85% by weight or more, preferably 90% by weight or more, is a useful resin L-LDP.
It is suitable as a raw material monomer for E and can be used as it is as a raw material monomer depending on the physical properties of L-LDPE. When the by-produced polymer is contained in the α-olefin polymer composition of the present invention, it can be removed by appropriately using a known solid-liquid separation device.

[0043]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded.

Example 1 A 2.4 liter autoclave heated and dried in a drier at 150 ° C. was assembled while hot, and then vacuum nitrogen substitution was performed. The autoclave was equipped with a stirrer equipped with a catalyst feed tube equipped with a rupture plate. n-heptane (98
0 ml), a solution of pyrrole (1.244 mmol) in n-heptane, triethylaluminum (8,000 mmo)
The n-heptane solution of 1) was charged on the barrel side of the autoclave, while the catalyst feed tube was solubilized with n-heptane of chromium (III) 2-ethylhexanoate (200 m).
g, 0.420 mmol). The total amount of n-heptane was 1 liter.

First, the autoclave is heated to 60 ° C.,
Then, ethylene was introduced from the catalyst feed pipe at 60 ° C. The rupture plate ruptured due to ethylene pressure, and the chromium compound was introduced into the barrel side of the autoclave to start low polymerization of ethylene. Ethylene was introduced until the total pressure reached 35 Kg / cm ² , then the total pressure was increased to 35 Kg / cm ² , and the temperature was adjusted to 6
Maintained at 0 ° C. After 1 hour, ethanol was pressed into the autoclave to stop the reaction.

After depressurizing the pressure of the autoclave and degassing, the by-produced polymer (mainly polyethylene) in the reaction solution was separated and removed by a filter to recover the α-olefin low polymer composition. In this example,
The shape of the by-product polymer was granular, and the filtering operation could be performed very well. Gas chromatograph α
-The results of the composition analysis of the olefin low polymer and the like are shown in Table 1.

Example 2 An α-olefin low polymer composition was obtained in the same manner as in Example 1 except that the reaction conditions shown in Table 1 were adopted. Table 1 shows the results of the composition analysis of the α-olefin low polymer by gas chromatography.

In the table, "HP" of the solvent type represents n-heptane, and the unit of catalyst efficiency is g-α-olefin / 1g.
-Chromium compound, the unit of catalytic activity is g-α-olephine / 1g-chromium · Hr. The catalyst component molar ratio represents the molar ratio of Cr compound: pyrrole: triethylaluminum.

[0049]

[Table 1] ────────────────────────────── Example 1 2 Solvent type (amount: L) HP (1) HP (1) Reaction temperature (℃) 60 60 Molar ratio of catalyst components 1: 3: 20 1: 3: 5 Ethylene pressure (Kg / cm ² ) 35 35 Reaction time (Hr) 1.0 1.0 <Product amount (g)> 102.6 57.4 <Composition distribution (wt%)> C ₄ 15.3 2.7 C ₆ overall 74.2 90.2 1-hexen content in C ₆ (wt%) 95.7 99.2 C ₈ 3.1 2.5 C ₁₀ C _10-20 6.8 4.3 C _22-30 0 0.1 Wax 0 <PE> 0.6 0.4 <Catalyst efficiency> 441 287 <Catalyst activity> 4239 2758 ──────────────────────────────

[0050]

According to the present invention described above, the reaction product composition obtained by the low polymerization reaction of α-olefin is rich in the polymer having the carbon number of 4 to 8, and therefore the fractional distillation is performed. Since the process load is small, an α-olefin low polymer composition that can be industrially advantageously used for various raw materials is provided, and the industrial value of the present invention is remarkable.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // C07B 61/00 300

Claims (4)

[Claims] 1. A reaction product composition obtained by a low polymerization reaction of α-olefin, wherein the content of the polymer having 4 to 8 carbon atoms is 90% by weight or more and 10 or more carbon atoms. The α-olefin low polymer composition, wherein the content of the polymer contained is 10% by weight or less. 2. The α-olefin low polymer composition according to claim 1, wherein the content of 1-hexene is 85% by weight or more. 3. The α-olefin low polymer composition according to claim 1, which is obtained by a low polymerization reaction using a catalyst system comprising at least a combination of a chromium compound and an amine or a metal amide and an alkylaluminum compound. 4. The α-olefin low polymer composition according to claim 3, which is obtained by a low polymerization reaction in which α-olefin and a chromium-based catalyst are brought into contact with each other in such a manner that the chromium compound and the alkylaluminum compound do not come into contact with each other in advance. .