JPH115806A - Production of olefinic wax - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an olefinic wax by which the olefinic wax can be obtained in high yield based on the catalyst unit and a step for removing a solvent can be simplified after the polymerization. SOLUTION: When an olefin is polymerized or copolymerized in the presence of a catalyst for polymerizing and olefin in the liquid phase while making hydrogen coexist in the polymerization system to produce an olefinic wax, the polymerization or copolymerization is carried out under conditions in which the liquid phase is composed of the olefinic wax or the olefinic wax and a hydrocarbon solvent to provide >=70 wt.% content of the olefinic wax in the resultant polymer liquid. In this case, ethylene is preferably polymerized or the ethylene is preferably copolymerized with other copolymerizable monomers to produce an ethylenic wax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an olefin wax excellent in productivity.

[0002]

BACKGROUND OF THE INVENTION Olefin waxes, such as ethylene waxes, are pigment dispersants, resin processing aids, printing ink additives, paint additives, rubber processing aids, fiber treatment agents, toner release agents, etc. Widely used for applications.

Conventionally, when such an ethylene wax is industrially produced, a highly active catalyst for producing polyethylene is usually used in order to obtain the wax in a high yield. Specifically, in the presence of a highly active catalyst, a large amount of hydrogen or a solvent is allowed to coexist in the polymerization system to polymerize ethylene (including copolymerization of ethylene with another olefin).
Ethylene wax is manufactured as a low molecular weight substance of polyethylene. As such a catalyst for producing polyethylene, a highly active titanium-based catalyst is usually used, and for example, a catalyst containing a highly active titanium catalyst component activated by a magnesium compound and an organic aluminum compound is used.

Further, a method of producing an ethylene wax using a vanadium catalyst (Japanese Patent Publication No. 60-39281), a metallocene compound of a transition metal selected from Group IVb, Vb and VIb of the periodic table; A method for producing an ethylene-based wax using a catalyst comprising an aluminoxane (JP-A-60-78462, JP-A-1-20
No. 3410, JP-A-6-49129) are also known.

[0005] Such an ethylene-based wax is conventionally generally produced by liquid phase polymerization, and usually, a large amount of hexane, cyclohexane,
Ethylene is polymerized using a hydrocarbon solvent such as decane and diesel oil while dissolving or suspending the wax produced by the polymerization in the hydrocarbon solvent. For example, Japanese Patent Publication No. 63-8125 describes that it is preferable to set the wax concentration in a polymerization (copolymerization) system to about 200 to 600 g / liter.

The present inventor has studied a method for industrially and efficiently producing an olefin wax such as an ethylene wax. As a result, the above-mentioned hydrocarbon solvent was not used as the polymerization solvent, or even if it was used. By using a small amount and substantially performing polymerization using the olefin-based wax itself as a polymerization solvent, an olefin-based wax can be obtained in a high yield per catalyst unit,
The inventors have found that the solvent removal step can be omitted or simplified after the polymerization, and that an olefin-based wax can be obtained with high productivity, thereby completing the present invention.

[0007]

An object of the present invention is to provide a method for producing an olefin wax which can obtain an olefin wax in a high yield per catalyst unit and can simplify a solvent removing step after polymerization. It is intended to be.

[0008]

In the method for producing an olefin wax according to the present invention, the olefin wax is polymerized or copolymerized in the liquid phase while hydrogen is present in the polymerization system in the presence of an olefin polymerization catalyst. In the production, the above-mentioned liquid phase is composed of an olefin-based wax or the above-mentioned polymerization or copolymerization is carried out under the condition of an olefin-based wax and a hydrocarbon solvent. Is 70% by weight or more. In the present invention, in the above,
The olefin wax is preferably an ethylene wax.

[0009]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the method for producing an olefin wax according to the present invention will be specifically described. In the present invention, the term "polymerization" may be used to mean not only homopolymerization but also copolymerization, and the term "polymer" refers to not only homopolymers but also copolymers. May be used with inclusive meaning.

In the present invention, when producing an olefin wax by polymerizing or copolymerizing an olefin in a liquid phase while hydrogen is present in the polymerization system in the presence of an olefin polymerization catalyst, the liquid phase is converted into an olefin-based wax. The above-mentioned polymerization or copolymerization is carried out under the condition comprising a wax based on olefin or a hydrocarbon solvent and the amount of olefin wax in the resulting polymerization solution is reduced to 7
0% by weight or more.

The above-mentioned olefin polymerization catalyst is preferably a highly active catalyst. If it is capable of polymerizing olefins with high activity, a known titanium-based catalyst, vanadium-based catalyst, metallocene-based catalyst and the like can be used. Can be used without particular limitation. Details of such a catalyst will be described later.

In the present invention, an olefin may be homopolymerized or copolymerized in the presence of a catalyst. As the olefin, specifically, an α-olefin having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-pentene,
1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4,4-
Dimethyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4-ethyl-1-hexene, 3-ethyl-1-
Hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene and the like.

Further, an olefin and another polymerizable monomer may be copolymerized. As other polymerizable monomers,
Vinyl chloride, vinyl acetate, vinyl acrylate, methyl methacrylate, tetrafluoroethylene, vinyl ether, acrylonitrile and other vinyl monomers, styrene, substituted styrenes, allylbenzene, substituted allylbenzenes, vinylnaphthalenes, substituted vinylnaphthalenes , Allylnaphthalenes, aromatic vinyl compounds such as substituted allylnaphthalenes, alicycles such as vinylcyclopentane, substituted vinylcyclopentanes, vinylcyclohexane, substituted vinylcyclohexanes, vinylcycloheptane, substituted vinylcycloheptanes, and allylnorbornane Group vinyl compound, cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl-1,4,5,8-dimetano-1,2,3,4,4a, 5,
Cyclic olefins such as 8,8a-octahydronaphthalene,
Allyltrimethylsilane, allyltriethylsilane, 4-
Silane unsaturated compounds such as trimethylsilyl-1-butene, 6-trimethylsilyl-1-hexene, 8-trimethylsilyl-1-octene, and 10-trimethylsilyl-1-decene; conjugated dienes such as butadiene and isoprene; Non-conjugated polyenes such as hexadiene, dicyclopentadiene, 5-vinyl-2-norbornene, acetylenes such as acetylene and methylacetylene, and aldehydes such as formaldehyde can be used.

In the present invention, among these, it is preferable to produce ethylene wax by homopolymerizing ethylene or copolymerizing ethylene with another polymerizable monomer. When producing an ethylene-based wax, ethylene and two or more other polymerizable monomers can be copolymerized. The amount of other monomers to be copolymerized is not particularly limited as long as the object of the present invention is not impaired, but it is usually desirable that the amount be 50 mol% or less.

In the present invention, the above-mentioned polymerization or copolymerization of olefins (hereinafter sometimes simply referred to as polymerization or (co) polymerization) is carried out in a liquid phase, and the resulting olefin wax forms a liquid phase.

In the present invention, this liquid phase can be formed only of an olefin wax. Further, the liquid phase may contain a hydrocarbon solvent having 20 or less carbon atoms. As such hydrocarbon solvents, specifically, propane, butane, pentane, hexane, heptane, octane, decane, dodecane, tetradecane, aliphatic hydrocarbons such as kerosene, cyclopentane, methylcyclopentane, cyclohexane, Alicyclic hydrocarbons such as methylcyclohexane, cyclooctane, and cyclohexene, and aromatic hydrocarbons such as benzene, toluene, and xylene can be used.

The liquid phase may contain a polymerization monomer which is liquid under the polymerization conditions, and may further contain a solvent supplied with the catalyst component, for example, n-hexane.

The hydrocarbon solvent can be used in an appropriate amount as needed as long as the concentration of the olefin wax in the obtained polymerization solution is 70% by weight or more. The wax concentration is 70% by weight or more, preferably 75 to 100% by weight.

The polymerization is carried out in the coexistence of hydrogen. The amount of hydrogen used is appropriately selected depending on the polymerization temperature, polymerization pressure, type of catalyst, molecular weight of the olefin wax, and the like. The pressure is about 3 kg / cm ² or more, preferably 5 kg / cm ² or more, and the ratio of hydrogen partial pressure / reactive monomer gas partial pressure is about 1 to 50, preferably about 2 to 35. desirable.

The polymerization temperature is usually 150 ° C. or higher, preferably 170 to 180 ° C., and the polymerization pressure is usually 20 kg / cm ^2.
G or more, preferably 35 to 45 kg / cm ² · G. The liquid phase is preferably stirred.

The polymerization may be carried out batchwise or continuously. When the concentration of the olefin-based wax in the obtained polymerization liquid is 70% by weight or more, the desolvation treatment can be easily performed, and the desolvation treatment step after the polymerization can be omitted or simplified. For example, it is also possible to remove the solvent simply by flushing the polymerization solution into a flash hopper.

According to the present invention as described above, an olefin-based wax can be produced in a high yield per unit catalyst. The viscosity average molecular weight of the olefin wax thus obtained, for example, the viscosity average molecular weight of the ethylene wax is from 500 to 5,000, preferably from 800 to 5,000.
The melt viscosity is desirably 5 to 1000 cP, preferably 10 to 500 cP.

In the production of the olefin-based wax as described above, a catalyst known as an olefin polymerization catalyst can be used without any particular limitation as described above, for example, a highly active titanium-based catalyst, a vanadium-based catalyst, a metallocene-based catalyst. A catalyst or the like can be used.

As an example of such a catalyst, for example, a titanium-based catalyst containing the following highly active titanium catalyst component can be preferably used. As the highly active titanium catalyst component, about 50 olefin polymer per 1 mg of titanium is used.
Those having the ability to produce g or more can be widely used, and specifically, a highly active titanium catalyst component activated by a magnesium compound is used. This highly active titanium catalyst component can be obtained by contacting a titanium compound and a magnesium compound by various methods.

The magnesium compound used for preparing such a highly active titanium catalyst component includes magnesium chloride, magnesium bromide, magnesium iodide, magnesium fluoride, magnesium hydroxide, magnesium oxide, magnesium hydroxyhalide, and alkoxy. Examples include magnesium, alkoxy magnesium halide, allyloxy magnesium, allyloxy magnesium halide, and alkyl magnesium halide. Two or more of these can be used in combination.

The magnesium compound may contain another metal or an electron donor. Examples of the titanium compound include a tetravalent titanium compound represented by Ti (OR) _g X _4-g (R is a hydrocarbon group, X is a halogen atom, and 0 ≦ g ≦ 4). Can be used.

More specifically, TiCl_Four, TiBr_Four, TiI_Four
Such as titanium tetrahalide, Ti (OCH_Three) Cl_Three, T
i (OC_TwoH_Five) Cl_Three, Ti (On-C_FourH₉) Cl_Three, Ti (OC
_TwoH_Five) Br_Three, Ti (O-iso-C_FourH₉) Br_ThreeSuch as trihalogen
Alkoxy titanium, Ti (OCH_Three)_TwoCl_Two, Ti (OC_Two
H_Five)_TwoCl_Two, Ti (On-C_FourH₉)_TwoCl_Two, Ti (OC_TwoH_Five)_TwoBr
_TwoDialkoxytitanium dihalides such as Ti (OC
H_Three)_ThreeCl, Ti (OC_TwoH_Five)_ThreeCl, Ti (On-C_FourH₉)_Three
Cl, Ti (OC_TwoH_Five)_ThreeMonohalogenated tris such as Br
Alkoxy titanium, Ti (OCH_Three)_Four, Ti (OC
_TwoH_Five)_Four, Ti (On-C_FourH₉)_Four, Ti (O-iso-C_FourH₉) _Four,
Ti (O-2-ethylhexyl)_FourSuch as tetraalkoxy
And the like.

Further, a trivalent titanium compound obtained by reducing a tetravalent titanium halide with aluminum, titanium, hydrogen, an organic aluminum compound or the like, for example, titanium trichloride can also be used.

Two or more of these titanium compounds can be used in combination. The highly active titanium catalyst component can be obtained as a solid having a large specific surface area by, for example, contacting the magnesium compound with the titanium compound as described above, or by contacting the solid magnesium compound with a large specific surface area with the titanium compound. To obtain a solid.

The solid titanium catalyst component is more specifically
(1) a co-grinding method of a magnesium compound and a titanium compound,
(2) a method of thermally reacting a solid magnesium compound and a titanium compound having a sufficiently large specific surface area, (3) a method of thermally reacting an oxygen-containing magnesium compound and a titanium compound, (4)
It can be obtained by, for example, a method of reacting a magnesium compound treated with an electron donor with a titanium compound.
In the method (4), the magnesium compound treated with the electron donor may be treated with an organoaluminum compound or a halogen-containing silicon compound as required before reacting with the titanium compound. Details of the method for preparing such a solid titanium catalyst component are described in, for example, JP-B-46-34092, JP-B-46-34094, JP-B-46-34098, and JP-B-47-41.
676, JP-B-47-46269, JP-B-50-32270, JP-B-53-1796, JP-B-60-39281, and JP-B-63-81.
No. 25, JP-A-62-50308, etc., and can be used in the present invention.

The highly active titanium catalyst component may be a liquid containing a magnesium compound, a liquefying agent, a titanium compound and, if necessary, a hydrocarbon solvent. The highly active titanium catalyst component as described above usually contains titanium, magnesium and halogen as essential components, and preferably contains titanium in an amount of about 0.2 to 18% by weight, more preferably about 0.2 to 18% by weight.
It is contained in an amount of 3 to 15% by weight. Further, in the catalyst component, the halogen / titanium (molar ratio) is desirably about 4 to 300, preferably about 5 to 200. When the catalyst component is a solid, more preferably preferably a specific surface area of about 10 m ² / g or more about 20~1000m ² / g is preferably about 40~900m ² / g.

In preparing the solid titanium catalyst component, in addition to the above-mentioned compounds, organic and inorganic compounds containing silicon, phosphorus, aluminum and the like used as a carrier and a reaction aid, if necessary, are used. May be used.
Examples of the carrier include Al ₂ O ₃ , SiO ₂ , B ₂ O
_{3, MgO, CaO, TiO 2} , ZnO, SnO 2, Ba
Resins such as O, ThO, and styrene-divinylbenzene copolymer can be used.

The titanium catalyst component as described above is used together with the following organoaluminum compound. During R ^a _n AlX _3-n (wherein, R ^a is a hydrocarbon group having 1 to 12 carbon atoms, X
Is halogen or hydrogen, and n is 1 to 3. R ^a is a hydrocarbon group having 1 to 12 carbon atoms such as an alkyl group, a cycloalkyl group or an aryl group, and specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an isobutyl group, Examples include a pentyl group, a hexyl group, an octyl group, a cyclopentyl group, a cyclohexyl group, a phenyl group and a tolyl group. Specific examples of such an organoaluminum compound include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, tri-2-ethylhexylaluminum, and alkenyl such as isoprenylaluminum. Dialkylaluminum halides such as aluminum, dimethylaluminum chloride, diethylaluminum chloride, diisopropylaluminum chloride, diisobutylaluminum chloride, dimethylaluminum bromide, methylaluminum sesquichloride, ethylaluminum sesquichloride, isopropylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesquichloride B Alkylaluminum sesquihalide such as bromide, methyl aluminum dichloride, ethyl aluminum dichloride,
Examples thereof include alkylaluminum dihalides such as isopropylaluminum dichloride and ethylaluminum dibromide, and alkylaluminum hydrides such as diethylaluminum hydride and diisobutylaluminum hydride.

As the organoaluminum compound, a compound represented by the following formula can also be used. In R ^a _n AlY _3-n the above formulas, R ^a is as defined above, Y is -OR
^b group, -OSiR ^c ₃ group, -OAlR ^d ₂ group, -NR
^e ₂ group, a -SiR ^f ₃ group or -N (R ^g) AlR ^h ₂ group, n is ^{1~2, R b, R c,} R d and R ^h
Is a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a cyclohexyl group, a phenyl group, etc., ^Re is hydrogen, a methyl group, an ethyl group, an isopropyl group, a phenyl group, a trimethylsilyl group, etc., and R ^f and R ^g Represents a methyl group, an ethyl group or the like.

Specific examples of such an organoaluminum compound include dimethylaluminum methoxide, diethylaluminum ethoxide, diisobutylaluminum methoxide, Et ₂ Al (OSiMe ₃ ), (iso-Bu) ₂ Al
(OSiMe ₃ ), (iso-Bu) ₂ Al (OSiEt ₃ ), Et ₂ A
lOAlEt ₂ , (iso-Bu) ₂ AlOAl (iso-Bu) ₂ , Me
₂ AlNEt ₂ , Et ₂ AlNHMe, Me ₂ AlNHEt, Et ₂
AlN (Me ₃ Si) ₂ , (iso-Bu) ₂ AlN (Me ₃ Si)
) ₂ , (iso-Bu) ₂ AlSiMe ₃ , Et ₂ AlN (Me)
—AlEt ₂ , (iso-Bu) ₂ AlN (Et) Al (iso-Bu) _{2 and the} like.

Further, an organoaluminum compound in which two or more aluminum atoms are bonded via an oxygen atom and a nitrogen atom, for example, (C ₂ H ₅ ) ₂ AlOAl (C ₂ H ₅ ) ₂ , (C
_{4 H 9) 2 AlOAl (C} 4 H 9) 2, (C 2 H 5) 2 AlN
And aluminoxanes such as (C ₂ H ₅ ) Al (C ₂ H ₅ ) ₂ and methylaluminoxane.

Two or more of these can be used in combination.
Among the above-mentioned organoaluminum compounds, they can be appropriately selected and used depending on the desired physical properties of the olefin wax.

In the present invention, the above-mentioned catalyst component may be pre-polymerized. The titanium catalyst component as described above is usually used in an amount of about 0.0001 to 1 mmol, preferably about 0.001 in terms of titanium atom per liter of polymerization volume.
Preferably, it is used in an amount of .about.0.5 mmol. The organoaluminum compound is used in an amount such that the Al atom in the compound is usually about 1 to 2000 mol, preferably about 5 to 500 mol, per 1 mol of Ti atom in the titanium catalyst component in the polymerization system. Is desirable.

The olefin polymerization catalyst used in the present invention may contain various other components useful for olefin polymerization, if necessary, in addition to the titanium catalyst component and the organoaluminum compound. Kosho 60-3
No. 9281, ethers having 2 to 20 carbon atoms, butyl chloride disclosed in JP-B-63-8125, halogen compounds of Groups 1 to 8 of the periodic table such as silicon tetrachloride, etc. Can be.

As the vanadium-based catalyst, for example, the catalyst disclosed in Japanese Patent Publication No. 60-39281 can be used, and as the metallocene-based catalyst, for example, JP-A-60-78462 and JP-A-Hei. −203
No. 410, JP-A-6-49129, JP-A-8
A catalyst disclosed in, for example, Japanese Patent Application No. 239414 can be used.

[0041]

According to the present invention, an olefin wax can be obtained in a high yield per catalyst unit,
After the polymerization, the solvent removing step can be simplified, the activity is improved under the same polymerization pressure, and an olefin wax can be produced with excellent productivity.

[0042]

EXAMPLES Next, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

[0043]

Example 1 In a reactor having an internal volume of 300 L (liter), triethylaluminum was added in an amount of 3.5 mmol / hr in terms of Al atoms and solid titanium catalyst component in an amount of 0.76 mmol / hr in terms of Ti atoms. 28 kg of ethylene
/ Hr, hydrogen 800 NL / hr, n-hexane 12 L / hr
, And ethylene was polymerized under the polymerization conditions shown in Table 1 to produce an ethylene wax having a viscosity average molecular weight of 2,400.

After the polymerization, the solvent could be removed only by flashing the obtained polymerization solution in a flash hopper. Table 1 shows the results.

[0045]

EXAMPLE 2 Table 1 shows polymerization conditions such as catalyst supply amount, ethylene supply amount, hydrogen supply amount, n-hexane supply amount, and polymerization pressure.
Except having changed to, an ethylene wax having a viscosity average molecular weight of 2300 was produced in the same manner as in Example 1.

After the polymerization, the solvent could be removed only by flashing the obtained polymerization solution in a flash hopper. Table 1 shows the results.

[0047]

EXAMPLE 3 Triethylaluminum was supplied in an amount of 3.5 mmol / hr in terms of Al atoms, and a solid titanium catalyst component was supplied in an amount of 0.50 mmol / hr in terms of Ti atoms. Ethylene was 28 kg / hr and hydrogen was 550 NL. / Hr, 7L of n-hexane
An ethylene wax having a viscosity average molecular weight of 3700 was produced in the same manner as in Example 1 except that the polymerization conditions were changed as shown in Table 1 except that the wax was continuously supplied at a rate of / hr.

After the polymerization, the solvent could be removed simply by flashing the obtained polymerization solution in a flash hopper. Table 1 shows the results.

[0049]

[Table 1]

[0050]

Example 4 In a reactor having an internal volume of 300 L, triethylaluminum was converted to 14.8 mmol / hr in terms of Al atoms.
A solid titanium catalyst component was supplied in an amount of 3.7 mmol / hr in terms of Ti atoms, ethylene was 28 kg / hr, and hydrogen was 17
00 NL / hr, n-hexane was continuously supplied at an amount of 11 L / hr, polymerization temperature was 170 ° C., polymerization pressure was 41.0 kg / cm.
Ethylene was polymerized under the conditions of ² G, a residence time of 3.7 hr, and a liquid phase polymer (ethylene-based wax) concentration of 76% by weight.

A polymerization solution having an ethylene wax concentration of 76% by weight (hexane concentration of 24% by weight) was obtained. The obtained polymerization solution could be desolvated only by flashing in a flash hopper. Remove n-hexane from the polymerization solution
An ethylene wax was obtained at 3 kg / hr. The polymerization activity per catalyst unit was 5.5 kg / mM-Ti. The viscosity average molecular weight of the ethylene wax is 900,
The melt viscosity was 13 cP and the density was 0.942 g / ml.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kenji Fujiyoshi 1-2-1, Waki, Waki-machi, Kuga-gun, Yamaguchi Prefecture Inside Mitsui Petrochemical Industry Co., Ltd.

Claims (2)

[Claims] 1. An olefin wax is produced by polymerizing or copolymerizing an olefin in a liquid phase while hydrogen is present in the polymerization system in the presence of an olefin polymerization catalyst. Or the above-mentioned polymerization or copolymerization is carried out under conditions consisting of an olefin wax and a hydrocarbon solvent, and the amount of the olefin wax in the obtained polymerization liquid is 70% by weight or more. A method for producing an olefin wax. 2. The method according to claim 1, wherein the olefin wax is an ethylene wax.