JP2003055404A - Process for preparation of ethylene copolymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for the preparation of an ethylene copolymer by using a polymerization catalyst of cluster halide. SOLUTION: The process for the preparation of an ethylene copolymer comprises a copolymerization of ethylene and 4-vinyl-1-cyclohexene in an aromatic hydrocarbon solvent, using a catalyst of cluster halide having a composition: (Ax Tiy Xz )n (wherein, A is an alkali metal atom; Ti is a titanium atom; X is a halogen atom; (x) is a number of 1-3; (y) is a number of 2-4; (z) is a number of 6-10; and (n) is a number of 4-10<6> ).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an ethylene copolymer using a catalyst comprising a cluster halide.

[0002]

2. Description of the Related Art Cluster-halides are metal halide clusters composed of a metal such as molybdenum and a halogen. As its structure, an octahedral cluster skeleton is known, and research on H. Schafer et al. Is known. ing. (H.schafer, HGvSchnering, J.Tillack, F.Kuhne
n, H.Wohrle, H.Baumann, Z.Anorg.Allg.Chem., 353,281 (19
67).). It is not known to use it as a catalyst or a carrier for a chemical reaction or a polymerization reaction. Further, regarding the polymer of cycloalkene, JP-A-6-199950,
JP-A-10-35438 and JP-A-10-3645.
No. 2 and Japanese Patent Application Laid-Open No. 3-163088.

[0003]

An object of the present invention is to provide a method for producing an ethylene copolymer using a polymerization catalyst composed of cluster halides.

[0004]

The present invention provides (A _x Ti _y X
_{z) n} becomes clusters halide having the composition (where, A is an alkali metal atom, Ti is titanium atom, X is a halogen atom, x is 1 to 3, y is 2 to 4, z is 6-10, or n,
Indicates 4 to 10 ⁶ . The invention relates to a method for producing an ethylene copolymer, which comprises copolymerizing ethylene and vinylcycloalkene in an aromatic hydrocarbon solvent using a catalyst consisting of

The present invention also relates to the above method for producing an ethylene copolymer, wherein the cluster halide is (Na ₂ Ti ₃ I ₈ ) _n .

The present invention also relates to the above method for producing an ethylene copolymer, characterized in that the aromatic hydrocarbon solvent is toluene.

The present invention also relates to the above method for producing an ethylene copolymer, wherein the vinyl cycloalkene is 4-vinyl-1-cyclohexene.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION (A _x Ti _y X _z ) _n in the present invention
Cluster halide having the following composition (where A is an alkali metal atom, Ti is a titanium atom, X is a halogen atom,
x is 1 to 3, y is 2 to 4, z is 6 to 10, and n is 4 to 10.
⁶ , preferably x is 2, y is 3, z is 8, and n is -1
Indicates 0. ) Has a structure in which the negative ion charge of Ti _y Cl _z is neutralized with K positive ions. It has a hexahedral structure.

A is an alkali metal atom, potassium,
Examples include sodium and rubidium. X is a halogen atom, and examples thereof include chlorine, bromine and iodine. As a specific cluster-halide, (K ₂ Ti ₃ C
l _{8) n,} and the like _{(Na 2 Ti 3 I 8)} n. As a manufacturing method, for example, in the case of (K ₂ Ti ₃ Cl ₈ ), it can be prepared from TiCl ₃ , Ti foil, and K metal as raw materials. Similarly, for (Na ₂ Ti ₃ I ₈ ),
It can be prepared from TiI ₄ , Ti foil, and Na metal.

As the preparation conditions, for example, TiCl ₃ , Ti foil and K metal are put into a quartz ampoule so that the molar ratio is preferably 1: 1: 1. All operations are performed in a nitrogen atmosphere. In addition, since the formation reaction does not proceed if water is present in the reaction system, the quartz ampoule is heated at a high temperature, preferably 500 to 1000 ° C., in order to remove water in advance.
The heat treatment is preferably performed for 10 to 30 hours. The quartz ampoule is sealed off and heated in an electric furnace, preferably at 520 ° C., preferably for 1 month.

As the organoaluminum compound used as a promoter for the α-olefin of the present invention, alkylaluminum, alkylaluminum halide and the like can be used. The alkyl group preferably has 1 to 2 carbon atoms.
0, particularly preferably 4 to 20 chain or branched saturated hydrocarbon groups, specifically methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group, heptyl Group, octyl group and the like.

Specific compounds include trimethyl aluminum, triethyl aluminum, tripropyl aluminum, triisopropyl aluminum, tributyl aluminum, triisobutyl aluminum, tripentyl aluminum, trihexyl aluminum, triheptyl aluminum, trioctyl aluminum, methyl alumoxane, Examples thereof include dimethyl aluminum chloride, diethyl aluminum chloride and ethyl aluminum dichloride. Trialkylaluminum is particularly preferable, and specific examples thereof include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum and the like.

Any of the above organoaluminum compounds can be used as a mixture. Further, polyaluminoxane, which forms a low polymer by the reaction of alkylaluminum and water, can be similarly used.

Examples of ethylene copolymers include copolymers of ethylene and vinyl cycloalkene. Examples of the vinyl cycloalkene include a copolymer of 4-vinyl-1-cyclohexene.

As a polymerization method, slurry polymerization can be used. Examples of the solvent for the slurry polymerization include aromatic hydrocarbons such as toluene, benzene and xylene, and among them, toluene is preferable. The solvent is preferably deoxygenated and dehydrated.

The amount of solvent used is 5 kg of ethylene at 70 ° C.
/ Cm ² , 0.5 to 1.2 liter is preferable, and 0.7 to 0.8 is particularly preferable. In addition to the above-mentioned slurry polymerization, a gas phase polymerization method in which a monomer is brought into contact with a catalyst in a gas state to carry out polymerization, or a bulk polymerization method in which a liquefied monomer is used as a solvent to carry out polymerization therein can be employed. In addition, either continuous polymerization or batch polymerization may be carried out by the above-mentioned polymerization method.

The polymerization pressure is usually 0.1 to 20 MPa, preferably 1 to 6 MPa, the polymerization temperature is usually 10 to 150 ° C.,
Preferably 30 to 100 ° C., particularly preferably 60 to 90
℃. The polymerization time is usually 0.1 to 10 hours, preferably 0.5 to 7 hours.

The amount of the cluster halide catalyst used is 70
2.0 × 10 against α-olefin 0.6 MPa at ℃
^-4 mol is preferable, and 1.0x10 ^{-5 to} 4.0x10 ^-4 mol is preferable. The size of the cluster halide catalyst is usually several hundreds of microns. The shape has a fused cluster structure composed of a single chain, a double chain, a plane layer, and the like.

The amount of the organoaluminum compound component used is
The Al / transition metal molar ratio to the transition metal atom of the catalyst solid component is 0.1 to 1500, preferably 1 to 1000.

The polymerization can be carried out by heating the catalyst in the presence of a monomer. The ethylene pressure is preferably 0.4 to 0.6 MPa, particularly 0.5 MPa
Is preferred. The temperature is preferably 60 to 80 ° C., particularly 7
0 ° C is preferred. The reaction time is preferably 1 to 8 hours,
Particularly, 4 hours is preferable.

The above polymerization may be carried out in the presence of hydrogen, and the pressure is preferably 0.2 MPa or less.

EXAMPLES In the examples, the melting point (Tm) and the heat of fusion (ΔH) are DSC (Seiko Denshi Kogyo SSC-5).
200 DSC-220C). The measurement method is 10 mg of sample 10 mg per minute from 23 to 230 ° C.
The temperature is raised at a rate of 5 minutes and held for 5 minutes, then 230
℃ to 40 ℃ at a rate of 5 ℃ per minute, 40 ℃ again
To 230 ° C. at a rate of 10 ° C./min, the melting point and the heat of fusion were measured.

Regarding the molecular weight and the molecular weight distribution, GPC using polystyrene as a standard substance (manufactured by Waters Co., Ltd. 15
0CV type, o-dichlorobenzene solvent, column SHO
DEX, temperature 145 ° C., concentration 0.05 wt%) ratio Mw / weight average molecular weight Mw and number average molecular weight Mn determined from Mw /
It was evaluated by Mn.

(Example 1) (Preparation method of cluster) As a preparation method, the volume was 5
TiCl ₃ (300 m
g), Ti foil (180 mg), and Na metal (44.7 mg)
In a molar ratio of 1: 1: 1. All operations are performed under a nitrogen atmosphere. In addition, since the production reaction does not proceed if a small amount of water is present in the reaction system, the quartz ampoule is previously heated at 800 ° C. for 24 hours to remove water,
Dehydrate. After inserting each raw material, the quartz ampoule was sealed off with a gas burner, completely sealed, and then heated in an electric furnace.
Heat at 20 ° C for 1 month. After one month, the ampoule is cooled to room temperature, opened under a nitrogen atmosphere, and the product is taken out. The product is a green-black crystal. The obtained cluster is a fused cluster having a layered shape, and has a composition of (Na ₂ Ti ₃ Cl ₈ ) _n .

(Example 2) (Polymerization method) 100 mg of the catalyst obtained in Example 1 and 10 mmol of triisobutylaluminum were dehydrated and deoxygenated with 800 ml of toluene and 40 ml of 4-vinyl-1-cyclohexene, and the inside was replaced with nitrogen. Placed in a 2 liter autoclave. The internal temperature of the autoclave was maintained at 70 ° C., and ethylene was added up to a pressure of 0.5 MPa. By supplementing with ethylene, the total pressure is 0.6
Polymerization was carried out for 4 hours while maintaining the pressure at 5 MPa. Polymerization activity was 0.46 (g-PE / g-cat · hr), 4-vinyl-1-cyclohexene unit in the obtained copolymer was 0.2 mol%, melting point was 135 ° C., heat of fusion (ΔH) was 144.6 (J / g).

Comparative Example 1 The same procedure as in Example 2 was carried out except that isooctane was used as the solvent. There was no 4-vinyl-1-cyclohexene unit in the copolymer, and it was an ethylene homopolymer.

[0026]

EFFECT OF THE INVENTION It is possible to provide a method for producing an ethylene copolymer using a catalyst comprising a cluster halide.

Claims (4)

[Claims] 1. A cluster halide having a composition of (A _x Ti _y X _z ) _n (where A is an alkali metal atom, Ti is a titanium atom, X is a halogen atom, x is 1 to 3, and y is 2 to 2).
4, z represents 6 to 10, or n represents 4 to 10 ⁶ . A method for producing an ethylene copolymer, which comprises copolymerizing ethylene and a vinylcycloalkene in an aromatic hydrocarbon solvent using a catalyst consisting of 2. The cluster halide is (Na ₂ Ti ₃ I
₈ ) _n , The method for producing an ethylene copolymer according to claim 1, wherein 3. The method for producing an ethylene copolymer according to claim 1, wherein the aromatic hydrocarbon solvent is toluene. 4. The vinylcycloalkene is 4-vinyl-
1-Cyclohexene, characterized in that
4. The method for producing an ethylene copolymer according to item 3.