JPH0261486B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses a highly active Ziegler catalyst to
This invention relates to a method for randomly copolymerizing ethylene and α-olefin with good yield. Olefin polymerization catalysts have made great progress since the discovery of Ziegler's catalyst. That is, highly active catalysts have been developed, and processes for producing polyethylene or polypropylene that do not require decatalyzing have been developed. On the other hand, catalysts for producing copolymer rubbers of ethylene and propylene have been produced using vanadium compound and organoaluminum compound catalysts that have good random copolymerizability of ethylene and propylene since these catalysts were developed. However, this catalyst has low polymerization activity at high temperatures, poor productivity, and the amount of catalyst used is large, so the aging of the rubber due to residual vanadium is significant, so it is necessary to remove the catalyst sufficiently. Recently, patents regarding highly active catalysts for copolymerizing olefins using titanium-based catalysts have been filed (Japanese Patent Application Laid-Open Nos. 104687-1987,
148093, Japanese Patent Application Laid-Open No. 120992/1983), it is not intended for rubber-like copolymers and does not fall outside the scope of modified polyolefin resins. In other words, JP-A-53-104687 aims at a polypropylene resin with a high propylene content in which the molar ratio of ethylene to propylene is 15/85 to 37/63 (89.5 to 71.5 wt% in terms of propylene content). , not a rubbery copolymer. Furthermore, JP-A-54-148093 specifies that the ethylene content in the copolymer of ethylene and α-olefin be 90 mol% or more, and aims at a polyethylene resin with a high ethylene content. Furthermore, JP-A-51-120992 relates to a catalyst for polymerization or copolymerization of olefins. According to the method described in the publication, MgCl ₂ and
When a complex containing TiCl ₃ or TiCl ₄ and an electron donor ligand is synthesized, for example, MgCl ₂ .TiCl ₃ .2CH ₃ COOC ₂ H ₅ ,
Depending on the type of ligand, such as MgCl ₂ .TiCl ₄ .6C ₅ H ₅ N, a stable complex in which a certain amount of ligand (2 to 10 moles/1 mole of Ti) is coordinated can be obtained. A complex in which such a large amount of ligands are stably coordinated has very low polymerizability, and what is particularly noteworthy is that the random copolymerizability of ethylene and propylene is low. As mentioned above, it is very difficult to obtain a rubber-like copolymer by copolymerizing ethylene and α-olefin with good randomness, and manufacturing polyolefins by homopolymerizing olefins or copolymerizing a small amount of other olefins. This cannot be inferred from technology at all. The present inventors have been conducting research on catalysts for producing olefin copolymer rubber for many years. As a result, they discovered a method of obtaining a rubber-like copolymer with unprecedented high activity and good random copolymerizability, resulting in the present invention. That is, the present invention prepares a homogeneous solution containing magnesium chloride, phosphate triester, and titanium tetrachloride in the presence or absence of an aromatic hydrocarbon, alicyclic hydrocarbon, or halogenated hydrocarbon, Produced by contacting the homogeneous solution with titanium tetrachloride in an amount of 2 to 1000 times the mole of magnesium in the homogeneous solution, the magnesium/titanium atomic ratio is 0.5 or more and 50 or less, and the phosphorus/titanium atomic ratio is 0.01.
The feature is that ethylene and α-olefin or ethylene, α-olefin and non-conjugated polyene are copolymerized using a catalyst consisting of a fine powder solid composite (A) and an organoaluminum compound (B) in a range of less than 2. This is a method for producing a rubbery olefin copolymer. The present invention will be explained in detail below. Regarding the catalyst component (A) used in the present invention, it is preferable that the magnesium chloride does not contain water of crystallization. Those subjected to modification treatments such as ball mill pulverization, vibration mill pulverization, and complexing treatment can also be used. Examples of phosphoric acid triesters include the following compounds. Trimethyl phosphate, triethyl phosphate, tri-n-propyl phosphate, tri-
i-propyl phosphate, tri-n-butyl phosphate, tri-i-butyl phosphate, tri-t-butyl phosphate, tri-n-hexyl phosphate, tri-n-octyl phosphate, tri-2- These include ethylhexyl phosphate, trilauryl phosphate, tricetyl phosphate, tristearyl phosphate, trioleyl phosphate, triphenyl phosphate, tritolyl phosphate, tricylyl phosphate, octyl diphenyl phosphate, and the like. Preferred are phosphoric triesters in which the alkyl group has 1 to 16 carbon atoms, particularly preferably the alkyl group has 2 to 12 carbon atoms. These compounds can also be used in combination of two or more. When preparing a solution containing magnesium chloride and a phosphoric triester, it may be prepared in a large amount of a phosphoric triester, or in the presence of an aromatic hydrocarbon, alicyclic hydrocarbon, or halogenated hydrocarbon solvent. You can also do it below. When the phosphorus compound is solid or waxy, it is necessary to carry out the reaction in the presence of these solvents. Specific examples of these solvents include benzene, toluene, xylene, cyclohexane, methylcyclohexane, methylene chloride, ethyl chloride,
Ethyl bromide, 1,2-dichloroethane, 1,
1-dichloroethane, n-butyl chloride, n-
Octyl chloride, monochlorocyclohexane,
Examples include monochlorobenzene and o-dichlorobenzene, but the solvent is not limited to these. Two or more of these solvents can be used in combination. Incidentally, it is preferable to add titanium tetrachloride to a solution containing magnesium chloride and phosphate triester so that the Ti/Mg atomic ratio is in the range of 0.2 to 2.0, preferably 0.5 to 1.5 to form a homogeneous solution. Next, a method for preparing the catalyst component (A) will be described. Although the method for preparing the liquid material containing magnesium chloride, phosphate triester, and titanium tetrachloride is not particularly limited, the following method may be mentioned. (1) Dissolve magnesium chloride in phosphate triester and dilute with the above solvent if necessary. Add titanium tetrachloride to the solution. (2) Triester phosphate is added to a solid powder obtained by co-pulverizing magnesium chloride and titanium tetrachloride using a vibration mill, ball mill, etc., and dissolved. Dilute with the above solvent if necessary. (3) Add magnesium chloride, titanium tetrachloride, phosphoric acid triester, and the above solvent if necessary,
Wet grind and dissolve using a vibration mill, ball mill, etc. Examples include, but are not limited to, these methods. The obtained homogeneous solution is desirably aged at -20 to 150°C, preferably at 0 to 100°C for 5 minutes to several hours. Next, a method for precipitating a finely powdered solid composite of catalyst component (A) from a solution containing the magnesium, titanium, and phosphorus compounds described above will be described. A fine powder solid composite can be obtained by adding titanium tetrachloride in an amount of 2 to 1000 times the mole, preferably 2.5 to 500 times the mole of magnesium in the homogeneous solution containing the above magnesium, titanium, and phosphorus compound. . The temperature at this time is in the range of -20°C to 150°C, preferably 0°C to 100°C. When performing precipitation treatment of the fine powder solid composite,
This can be carried out in the presence of an inorganic solid carrier. The inorganic solid carrier has a surface area of 50 m ² /g or more, preferably 60 m ² /g or more, and an average particle size of 200 μ or less,
Preferably 150 μ or less, average pore diameter 50 Å or more,
Preferably an inorganic solid with a diameter of 60 Å or more, such as silica,
Examples include alumina, zeolite, and magnesia. The finely powdered solid composite prepared as described above is preferably washed thoroughly with pentane, hexane, heptane, toluene, etc., and then used as a polymerization catalyst in a suspended state in these solvents. When the infrared absorption spectrum of the thoroughly washed finely powdered solid composite is measured by the KBr tablet method, characteristic absorption of phosphoric triester is observed. Further, after the solid composite was decomposed with water, the amount of phosphoric triester present was determined by gas chromatography. Furthermore, titanium was fixed by a colorimetric method, and magnesium was fixed by an atomic absorption method. Mg/Ti (atomic ratio) in the solid composite = 0.5 to 50, preferably 0.6 to
10. P/Ti (atomic ratio) must be in the range of 0.01 or more and less than 2, preferably 0.05-1. The amount of inorganic solid carrier to be used when precipitating a finely powdered solid composite from a solution containing magnesium, titanium, and phosphorus compounds is 0.5 to 200 g, preferably 1 to 100 g, per 1 g of magnesium chloride used.
g range. As the catalyst component (B), an organic aluminum compound is used. General formula AlRmX _3-n (R is a hydrocarbon residue having 1 to 12 carbon atoms, X is a halogen or alkoxy group,
m is an organoaluminum compound represented by 1 to 3). For example, trimethylaluminum, triethylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, tri-n-dodecylaluminum, diethylaluminum chloride, diethylaluminium bromide, diethylaluminium iodine Do, G-n
-Butylaluminum chloride, diisobutylaluminum chloride, di-n-octylaluminum chloride, ethylaluminum sesquichloride, isobutylaluminum sesquichloride, n
- Examples include, but are not limited to, octylaluminum sesquichloride, ethylaluminum dichloride, n-butylaluminum dichloride, isobutylaluminum dichloride, n-octylaluminum dichloride, ethylaluminum dibromide, diethylaluminum monoethoxide, diethylaluminium monobutoxide, etc. It is not something that will be done. Moreover, two or more kinds of compounds can be used in combination. Preferred is a trialkylaluminum or a mixture of a trialkylaluminum and a halogen-containing organic aluminum. As monomers for polymerization, ethylene and one or more types of α
- Olefin can be used. Specific examples of α-olefin include propylene, butene-1,
Examples include pentene-1, hexene-1, 4-methylpentene-1, octene-1, and the like. Non-conjugated polyene monomers can be copolymerized with the olefin monomers to facilitate vulcanization of the copolymer rubber. Specific examples of non-conjugated polyenes include dicyclopentadiene, tricyclopentadiene, 5-methyl-2,5-norbornadiene, 5-methylene-2-norbornene,
5-ethylidene-2-norbornene, 5-isopropylidene-2-norbornene, 5-isopropenyl-2-norbornene, 5-(1'-butenyl)
-2-norbornene, 5-(2'-butenyl)-2
-norbornene, 1,5,9-cyclododecatriene, 6-methyl-4,7,8,9-tetrahydroindene, 2,2'-dicyclopentenyl, trans-1,2-divinylcyclobutane, 1,4-
Hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,6
-Octadiene, 6-methyl-1,5-heptadiene, etc. These non-conjugated polyenes are added to the polymerization reactor in a necessary amount so that the iodine value in the copolymer is 2 to 50, preferably 3 to 40. At this time, two or more types of non-conjugated polyenes can also be used in combination. Polymerization temperature is usually 10-150℃, preferably 30-120℃
It is ℃. Polymerization pressure is usually 100Kg/cm ² at normal pressure.
is within the range of Copolymerization can be solution polymerization or suspension polymerization. It can be carried out in the form of suspension polymerization using propylene as a solvent, suspension polymerization using a solvent in which the produced polymer has a low solubility, and solution polymerization using a solvent in which the produced polymer has a high solubility. Solution polymerization is preferred. Specific examples of polymerization solvents are listed below. Hydrocarbon solvents include hexane, heptane, octane, kerosene,
Benzene, toluene, xylene, cyclohexane, halogenated hydrocarbon solvents include methylene chloride, monochloroethane, 1,1-dichloroethane, 1,2-dichloroethane, 1,2-dichloropropane, monochlorobutane, monochlorobenzene, and the like. Two or more of these solvents can be used in combination to adjust the solvability parameter (SP value). The molecular weight of the copolymer can be arbitrarily adjusted by using hydrogen, if necessary. Next, the present invention will be explained in more detail with reference to Examples. In addition, the measured values of various physical properties of the copolymer in the examples were as follows: Mooney viscosity was preheated for 1 minute, measurement was performed for 4 minutes, and temperature was
The propylene content was determined by infrared absorption spectrum, the iodine value was determined by titration, and the 100% modicolus, tensile strength, elongation at break, and Shore A hardness were determined by a measurement method based on JISK 6301. . The phosphoric acid triester in the catalyst component (A) (solid composite) was determined by using a gas chromatogram after decomposing the catalyst component (A) slurry into water. The titanium content was determined by a colorimetric method using hydrogen peroxide as a coloring agent after decomposition with phosphoric acid. Examples 1 to 4 (1) Preparation of catalyst component (A) (solid composite) A rotor and 1 g of anhydrous magnesium chloride were placed in a 100 ml flask that had been thoroughly dried and purged with nitrogen.
(10.5 mmol). When a specified amount of the solvent listed in Table 1 dried with molecular sieves and a specified amount of the phosphorus compound listed in Table 1 were added and stirred at room temperature for 20 minutes, the magnesium chloride was completely dissolved and a colorless and transparent homogeneous solution was obtained. . Add 1.16ml of titanium tetrachloride to this homogeneous solution.
(10.5 mmol) was added and left to stand for 30 minutes. It became a yellow transparent homogeneous solution. When 12 ml of titanium tetrachloride was gradually added to this solution while stirring, a yellow fine powder was produced. After continued stirring for 2 hours, a yellow fine powder solid complex was precipitated and the supernatant was separated. Add 80ml of freshly dried n-hexane and add 30ml of freshly dried n-hexane.
The mixture was stirred and washed for a minute. This washing operation was repeated six times. A yellow-white finely powdered solid composite was obtained. n
- Add hexane to make a 50ml slurry. (2) Ethylene, propylene and 5-ethylidene-2
-Copolymerization of norbornene The separable flask in step 3 was equipped with a stirring blade, a three-way pot, a gas blowing tube, a thermometer, and a dropping funnel for adding 5-ethylidene-2-norbornene, and the flask was sufficiently purged with nitrogen. This flask was dried with molecular sieves and degassed.
Added 2 hexane. Dry ethylene 4/min, propylene 6/min through the gas blowing pipe
/min, hydrogen 0.2/min was bubbled into the flask temperature-controlled at 35℃ for 10 minutes, and 1 mol/min of triisobutylaluminum was added.
After adding 2 ml of n-hexane solution, 0.05 mmol of the n-hexane slurry of catalyst component (A) prepared in (1) above was added in terms of titanium atoms to initiate polymerization. Simultaneously with the start of polymerization, a mixed solution of 10 ml of 5-ethylidene-2-norbornene and 200 ml of n-hexane was added dropwise at a rate of 7 ml/min, and polymerization was carried out for 30 minutes. During the polymerization, a monomer mixed gas was passed through the reactor at the above flow rate. The polymerization temperature was controlled at 35°C by external cooling. Almost no gel formation was observed during copolymerization. After 30 minutes, 20 ml of methanol was added to stop the polymerization. After adding a small amount of anti-aging agent, steam stripping was performed to obtain a solid rubber. The yield, Mooney viscosity, and propylene content in the copolymer were measured. The results are summarized in Table 1. The raw rubber physical properties of the copolymer obtained in Example 1 seemed to be decreased. 100% modulus = 7 Kg/cm ² Tensile strength = 17 Kg/cm ² Elongation at break = 4500% Shore A hardness = 32 Comparative example 1 Tri-n-butyl phosphate used in Example 1 [OP (OC ₄ H ₉ ) ₃ ] Instead of tri-n-butyl phosphite [P(OC ₄ H ₉ ) ₃ ], an attempt was made to prepare a solid composite by performing the same procedure as in Example 1, but the solid composite The body did not precipitate. This comparative example shows that the phosphorus compound requires an O=P bond. Comparative Example 2 Example 1 except that n-hexane was used instead of the monochlorobenzene solvent used in Example 1.
An attempt was made to prepare a solid composite using the same procedure as above, but an oily precipitate was formed and no solid composite was precipitated. This comparative example shows that the solvent used is important. Comparative Example 3 A catalyst was prepared by the method of Examples 9 and 14 of JP-A-51-120992. Copolymerization was attempted using 0.05 mmol of Ti according to the method of Example 1, but no copolymer was obtained. When copolymerization was carried out by increasing the amount of catalyst used tenfold (0.5 mmol for Ti and 20 mmol for triisobutylaluminum), 6.5 g of copolymerization was obtained. The catalyst yield was 270 g/g-Ti, indicating very low activity.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 shows a flowchart showing the catalyst preparation process of the present invention.

Claims (1)

[Claims] 1. Prepare a homogeneous solution containing magnesium chloride, phosphate triester, and titanium tetrachloride in the presence or absence of an aromatic hydrocarbon, alicyclic hydrocarbon, or halogenated hydrocarbon, and mix the homogeneous solution with the titanium tetrachloride. Produced by contacting 2 to 1000 times the molar amount of titanium tetrachloride to magnesium in a homogeneous solution.
Magnesium/titanium atomic ratio is 0.5 or more and 50 or less,
A finely powdered solid composite (A) with a phosphorus/titanium atomic ratio in the range of 0.01 or more and less than 2 and an organoaluminum compound
A method for producing a rubbery olefin copolymer, which comprises copolymerizing ethylene and α-olefin or ethylene, α-olefin and non-conjugated polyene using a catalyst comprising (B).