JPH037686B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an olefin copolymer rubber with good processability, high tensile strength, and excellent random copolymerizability in a high yield using a Ziegler catalyst soluble in a solvent. As a catalyst for producing a rubbery copolymer by randomly copolymerizing two or more types of olefins, a combination catalyst of a homogeneous vanadium compound and an organoaluminium compound has conventionally been widely used. However, these homogeneous vanadium catalysts are generally very easily deactivated during polymerization, and their activity is not very high at a practical polymerization temperature of 30 to 60°C. On the other hand, a combination catalyst of a titanium compound and an organoaluminum compound is generally known as a catalyst that exhibits relatively little deactivation during polymerization. However, when this titanium compound is used as a catalyst, each olefin tends to be homopolymerized, resulting in a mixture of individual homopolymers, or even if copolymerized, it tends to be blocky, and a rubber-like copolymer is not formed. I can't get it. Recently, several patent applications have been filed for inventions for producing ethylene/α-olefin elastic copolymers using titanium-based catalysts. Examples include JP-A-49-51381, JP-A-50-117886,
There are Japanese Patent Laid-Open No. 53-104687, etc. These catalysts are a combination of a solid catalyst component with a titanium compound supported on a carrier and an organic aluminum compound component.
This method attempts to copolymerize ethylene and α-olefin randomly, but because the randomness of the resulting copolymer is not good, a portion of it precipitates in the hydrocarbon solvent during polymerization. Therefore, it is difficult to carry out solution polymerization as long as these catalysts are used. Therefore, the present inventors believed that it would be difficult to produce random copolymers of olefins using a solid catalyst, and by using a titanium-based homogeneous catalyst, an olefin copolymer with excellent random copolymers was developed. We have been conducting intensive research to obtain rubber with high yield. In addition, a patent application has been filed for a method of copolymerizing olefins using a catalyst consisting of a titanium compound component soluble in the polymerization solvent, a magnesium halide component soluble in the polymerization solvent, and an organoaluminum compound (Japanese Patent Laid-Open No. 1983-1979-1). Publication No. 78004). The method of this patent requires a large amount of alcohol as a solubilizing agent in order to dissolve the magnesium halide in the polymerization solvent. In order to attempt copolymerization of olefins using this homogeneous solution, the polymerization activity is low with the usual amount of organoaluminum compound used, and a large amount of organoaluminum compound is required, which is economically disadvantageous. The present inventors discovered a method of uniformly dissolving magnesium halide in a polymerization solvent without containing active hydrogen compounds, and using this homogeneous solution, ethylene and α
- As a result of extensive research into methods for random copolymerization of olefins, the present invention was achieved. That is, in producing a rubbery copolymer by copolymerizing ethylene and α-olefin or ethylene and α-olefin and a non-conjugated diene, the present invention comprises: (A) a hydrocarbon solvent-soluble titanium compound; and (B) general formula

[Formula] (However, R ₁ , R ₂ , R ₃ are the same or different hydrocarbon residues or halogenated hydrocarbon residues having 1 to 20 carbon atoms, n ₁ , n ₂ , n ₃
represents 0 or 1. ) A method for producing an olefin copolymer rubber characterized by using a catalyst consisting of a magnesium halide solubilized in a hydrocarbon or a halogenated hydrocarbon, and (c) an organoaluminum compound. This is what we provide. The invention will now be described in more detail. The catalyst component (A) used in the present invention is a titanium compound soluble in a hydrocarbon solvent, and has the general formula Ti(OR) _o
It is a compound represented by X _4-o (R is a hydrocarbon residue having 1 to 12 carbon atoms, X is a halogen, 0≦n≦4). For example, TiCl ₄ , TiBr ₄ , TiI ₄ , Ti(OCH ₃ )
_Cl3 , Ti _{( OC2H5} ) _Cl3 , Ti _{( OC4H9} ) _Cl3 , Ti
(OC ₈ H ₁₇ ) Cl ₃ , Ti (OC ₁₂ H ₂₅ ) Cl ₃ , Ti (OC ₆ H ₅ )
Cl ₃ , Ti(OC ₂ H ₅ ) ₂ Cl ₂ , Ti(OC ₂ H ₉ ) ₂ Cl ₂ , Ti
(OC ₈ H ₁₇ ) ₂ Cl ₂ , Ti(OC ₂ H ₅ ) ₃ Cl, Ti(OC ₄ H ₉ ) ₃ Cl,
Ti(OC ₂ H ₅ ) ₄ , Ti(OC ₈ H ₁₇ ) ₄ , Ti[OCH ₂ CH
( _C2H5 ) _{C4H9 ] 4 ,} Ti _{( OC2H5} ) ₂ ( _OC4H9 ) _{2 ,} etc. Titanium tetrahalide is preferred, and titanium tetrachloride is particularly preferred. These titanium compounds are preferably used after being dissolved in the polymerization solvent described below. There are magnesium halides MgCl ₂ , MgBr ₂ , and MgI ₂ used in the preparation of catalyst component (B) in the present invention,
Preferably, it does not contain water of crystallization. Note that it is possible to use a material that has been subjected to a modification treatment such as ball mill pulverization or complexation treatment. The phosphorus compound that can be used in the preparation of the catalyst component (B) in the present invention has the general formula

[Formula] (where R ₁ , R ₂ , R ₃ are the same or different hydrocarbon residues or halogenated hydrocarbon residues having 1 to 20 carbon atoms, n ₁ ,
n ₂ and n ₃ are 0 or 1. ) are used, and specific examples thereof include the following compounds. (1) Trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, triisobutyl phosphate, tri-n-octyl phosphate, tri-2-ethylhexyl phosphate, trilauryl phosphate, tricetyl phosphate, Tristearyl phosphate, trioleyl phosphate, tritolyl phosphate, trixylenyl phosphate, tolyldiphenyl phosphate, octyl diphenyl phosphate, xylenyl diphenyl phosphate, trichloroethyl phosphate, tridichloropropyl phosphate ate, (2) n-butyl (di-n-butoxy) phosphine oxide, n-octyl (di-n-octyloxy) phosphine oxide, 2-ethylhexyl (di-2-ethylhexyloxy) phosphine oxide, diethyl (ethoxy)phosphine oxide, di-n-butyl (n-butoxy) phosphine oxide, diisobutyl (isobutoxy) phosphine oxide, di-n-octyl (n-octyloxy) phosphine oxide,
Di-2-ethylhexyl (2-ethylhexyloxy)phosphine oxide, triethylphosphine oxide, tri-n-propylphosphine oxide, tri-n-butylphosphine oxide, tri-isobutylphosphine oxide,
These include tri-n-octylphosphine oxide, tri-2-ethylhexylphosphine oxide, tricyclohexylphosphine oxide, and the like. However, it is not limited to these arranged compounds. Preferably, the hydrocarbon residue or halogenated hydrocarbon residue is a chain phosphorus compound. Particularly preferably R ₁ , R ₂ and R ₃ have 4 to 8 carbon atoms
It is a phosphorus compound that is a chain hydrocarbon residue or a halogenated hydrocarbon residue. The amount of the phosphorus compound used in the present invention is in the range of 1 to 30 mol, preferably 2 to 10 mol, per 1 mol of magnesium halide. The solvent used to treat and dissolve the magnesium halide and phosphorus compound is a saturated aliphatic hydrocarbon having 5 to 12 carbon atoms, such as n-pentane, n-hexane, n-heptane, n-octane, isooctane, n-decane. , n-dodecane, etc. Among them, n-hexane and n-heptane are preferred. Also, alicyclic hydrocarbons having 6 to 9 carbon atoms, such as cyclohexane, methylcyclohexane, and ethylcyclohexane. Among them, cyclohexane is preferred. Furthermore, aromatic hydrocarbons having 6 to 9 carbon atoms, such as benzene, toluene, xylene,
Mesitylene, etc. Among them, benzene and toluene are preferred. Furthermore, halides of saturated aliphatic hydrocarbons having 1 to 12 carbon atoms, such as methylene chloride, ethyl chloride, ethyl bromide, 1,2
-dichloroethane, 1,1-dichloroethane, -n-butyl chloride, -n-octyl chloride, etc. Among them, methylene chloride and 1,2-dichloroethane are preferred. Among these listed solvents, n-hexane,
Particularly preferred are n-heptane, cyclohexane, methylene chloride, and 1,2-dichloroethane. Two or more of these solvents can also be used in combination. The treatment temperature for magnesium halide and phosphorus compound is -30 to 120°C, preferably 0 to 60°C. The above-mentioned solvent may be added after the treatment of the magnesium halide and the phosphorus compound, or the treatment may be conducted in these solvents. A vanadium compound soluble in a hydrocarbon solvent can also be added to the catalyst component (A) or (B). The addition of small amounts of vanadium compounds can significantly increase the polymerization activity. Vanadium compounds soluble in hydrocarbon solvents include vanadium tetrachloride, oxyvanadium trichloride, and alcohol-modified compounds of these vanadium compounds. Vanadium tetrachloride and oxyvanadium trichloride are preferred. The amount of vanadium compound added is: V/Ti=0.01-5, preferably 0.05-1 (molar ratio)
It is. The method of adding the vanadium compound is not particularly limited, and preferred methods include adding it to the catalyst component (A), adding it to the catalyst component (B), and adding it after contacting the catalyst components (A) and (B). . The organoaluminum compound that can be used as the catalyst component (C) of the present invention has the general formula AlR _o X _3-o (R is a hydrocarbon residue having 1 to 12 carbon atoms, X is a halogen, 1≦n≦
3). For example, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-octylaluminum, tri-n-dodecylaluminum, diisobutylaluminum iodide, di-n-butylaluminum chloride, Examples include diisobutylaluminum bromide, di-n-butylaluminum chloride, diisobutylaluminum bromide, ethylaluminum sesquichloride, isobutylaluminum sesquichloride, ethylaluminum dichloride, diethylaluminum ethoxide, and the like. A mixture of two or more of these organoaluminum compounds can also be used. Among these organoaluminum compounds, trialkylaluminum is preferred. The amount of component (C) used in the olefin copolymerization is 2 to 50 times, preferably 3 to 25 times, per mole of titanium compound. As monomers for polymerization, ethylene and at least 1
Species α-olefins are used. Specific examples of α-olefin include propylene, 1-butene,
1-pentene, 1-hexene, 4-methyl-1-
Examples include pentene and 1-octene. Among these, when copolymerizing ethylene and propylene, the content of propylene units in the copolymer is 20
-90% by weight, preferably 25-80% by weight. In addition, to facilitate the vulcanization of copolymer rubber,
Monomers of non-conjugated polyenes can be copolymerized with the olefin monomers. The non-conjugated polyene is selected from those of arbitrary formation such as cross-linked hydrocarbon compounds, monocyclic compounds, heterocyclic compounds, chain compounds, and spiro-type compounds. Specifically, 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,
Examples include 1,6-octadiene, 6-methyl, and 1,5-heptadiene. These non-conjugated polyenes have an ioso value in the copolymer of 2 to 50, preferably 3.
Add the required amount to the polymerization reactor to make ~40. Among these monomers, dicyclopentadiene and 5-ethylidene-2-norbornene are preferred. Polymerization solvents that can be used in the present invention include 2-hexane, 2-heptane, n-octane, etc. having 5 carbon atoms.
~20 hydrocarbon solvents are preferably used. When copolymerizing ethylene and α-olefin or these and non-conjugated cyanide, there are many methods for contacting each catalyst component, but typical examples are shown below. As the olefin monomer used here, the same monomer as the monomer for polymerization described above can be used. Preferably propylene, 1-butene, 1-
Hexene, 1-octene and mixtures of these monomers with ethylene. After contacting catalyst components (A) and (B), in the presence of an olefin monomer (preferably propylene or ethylene and propylene) at a temperature below 15°C.
(C) Contact with component. Catalyst components (A), (B), and (C) are brought into contact in the presence of an olefin monomer (preferably propylene or ethylene and propylene) at a temperature of 15° C. or lower. However, the contact method is not limited to these methods, but the following methods are preferred. The concentration of component (A) when each catalyst component comes into contact is generally 0.01
-100mM/, preferably 0.1-50mM/. The quantitative ratio of Mg and Ti in catalyst components (B) and (A) is Mg/
Ti=0.1-100 (molar ratio), preferably 0.1-100
10 (molar ratio). Also (C)/(A)=2~50
(molar ratio), preferably in the range of 5 to 25 (molar ratio). The temperature when contacting catalyst components (A) and (B) and then contacting component (C) or contacting catalyst components (A), (B), and (C) is
The temperature is 15°C to -50°C, preferably 10°C to -30°C. As the monomer that can be present during contact with the catalyst components, the above-mentioned olefin monomer is preferable,
Propylene is particularly preferred, especially mixtures of ethylene and propylene. Taking a mixture of ethylene and propylene as an example, it can be used in any quantitative ratio, but the preferred mixing ratio is ethylene/propylene=0.01 to 10. The amount of these monomers is preferably equal to or more than the mole of component (C), preferably 5 times or more. Polymers formed by low-temperature contact of monomers and catalysts are
It ranges from 0.001 to 10 wt%, preferably from 0.01 to 5 wt%. The copolymerization reaction may be batch polymerization or continuous polymerization. Polymerization temperature is 0~200℃, preferably 20℃~120℃
It is ℃. Polymerization pressure usually ranges from normal pressure to 50 kg/cm ² . The molecular weight of the copolymer can be arbitrarily adjusted by using hydrogen as 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, measured for 4 minutes, and the temperature
By measuring at 100℃, propylene content by infrared absorption spectrum, iodine number by titration method, 100% modulus, tensile strength, elongation at break,
and Shore A hardness are values determined by a measuring method according to JISK6301. In the following Examples and Comparative Examples, the infrared absorption spectra of 730 cm ^-1 (absorption due to crystallinity of polyethylene) and 720 cm ^-1 ((-CH ₂ −) _o
The intensity ratio (absorption due to skeletal vibration) was expressed as shown in Figure 2, and the area of each was determined and calculated using the following formula to determine the random index (RI). R・I・(%)=(Area of B)/(Area of A+B)×
100 Examples 1 to 4 (1) Dissolution of magnesium chloride A rotor and 1 g of anhydrous magnesium chloride (10.5
mmol), dried with molecular sieves, dehydrated n-hexane (30 ml) and 2-ethylhexyl (di-2-ethylhexyloxy)phosphine oxide (19.3 ml (42 mmol)), and stirred at room temperature for 20 minutes to dissolve magnesium chloride. It was completely dissolved to obtain a colorless and transparent homogeneous solution. N-hexane was added to bring the total volume to 52.5 ml (0.2 mol/solution with magnesium chloride). (2) Copolymerization of ethylene and propylene A stirring blade, a three-way pot, a gas blowing tube, and a thermometer were attached to the separable flask in step 3, and the flask was sufficiently purged with nitrogen. N-hexane 2, which had been dried with molecular sieves and degassed, was placed in the flask. Dry ethylene through the gas blow pipe
/min, propylene 7/min and hydrogen 0.2
/min of mixed gas was bubbled through the flask whose temperature was controlled at 35°C for 10 minutes. On the other hand, put a three-necked 300ml flask into a three-necked flask.
A two-way tank, rotor, and thermometer were attached, and the system was sufficiently purged with nitrogen. dry n-hexane 200
ml and cooled to the predetermined temperature listed in Table 1.
A mixed gas of 0.5/min of ethylene and 2/min of propylene was blown into this flask. Next, 7 mmol of triisobutylaluminum (1 mol/
n-hexane solution) was added. 10 ml of the magnesium chloride solution prepared in (1) was placed in a 50 ml flask purged with nitrogen, and 10 ml of a 0.2 mol/n-hexane solution of titanium tetrachloride was added thereto, followed by thorough stirring. 7ml of this solution (0.7ml of Ti)
M) was placed in the 300 ml flask. 1 minute later,
A Teflon tube was connected to a two-way pot, and the liquid was transferred all at once to the above-mentioned 3 separable flask prepared in advance under nitrogen pressure to start copolymerization.
Ethylene, propylene, and hydrogen were supplied at the above flow rates, and copolymerization was carried out for 30 minutes. During the copolymerization, the polymerization temperature was controlled at 35°C by external cooling. No gel formation was observed during the copolymerization. After 30 minutes, stop supplying the mixed gas of ethylene, propylene and hydrogen, and add 20ml of methanol.
was added to stop the polymerization. A small amount of anti-aging agent and a small amount of dispersant were added, 1 part of water was added, and the mixture was thoroughly stirred, followed by steam stripping to obtain a solid rubber. The yield, Mooney viscosity, propylene content in the copolymer, and random index (R.I.) were measured. The results are summarized in Table 1. The raw rubber physical properties of the copolymer obtained in Example 3 were as follows. ML100℃ 1+4=42 100% modulus = 5Kg/cm ² Tensile strength = 16Kg/cm ² Elongation at break = 3400% Shore A hardness = 37 Examples 5, 6 2-ethylhexyl (di-
The same procedure as in Example 1 was carried out, except that the phosphorus compounds listed in Table 1 were used in place of 2-ethylhexyloxy)phosphine oxide. Table 1 shows the results.
summarized in. Example 7 2-ethylhexyl (di-
Using the phosphorus compounds listed in Table 1 instead of 2-ethylhexyloxy)phosphine oxide, and adding 7 mmol of triisobutylaluminum to a 300 ml three-necked flask in Example 1, titanium tetrachloride was added.
3.5 ml of 0.2 mol/n-hexane solution was added, followed by 3.5 ml of magnesium chloride solution (0.2 mol/). The subsequent operations were the same as in Example 1. The results are summarized in Table 1. Example 8 In the copolymerization of Example, a total amount of 6 ml of 5-
The same operation as in Example 1 was carried out except that ethylidene-2-norbornene was continuously supplied.
The results are summarized in Table 1. Example 9 The same operation as in Example 8 was carried out except that dicyclopentadiene was used in place of 5-ethylidene-2-norbornene used in Example 8. The results are summarized in Table 1. Comparative Example 1 (1) Dissolution of Magnesium Chloride In place of the magnesium chloride solubilizer 2-ethylhexyl (di-2-ethylhexyloxy)phosphine oxide used in Example 1, n
-Example 1 except that 8.0 ml (42 mmol) of dodecyl alcohol was used and heating was performed at 65°C for 2 hours.
The same operation as in (1) was performed to obtain a uniform colorless and transparent solution. (2) Copolymerization of ethylene and propylene The same operation as in Example 1-(2) was carried out except that the magnesium chloride solution obtained in (1) above was used. A large amount of fibrous gel was produced during copolymerization, and no rubbery copolymer was obtained. Comparative Example 2 The same operation as in Example 3 was performed except that a solution containing magnesium chloride and a phosphorus compound was not used when copolymerizing ethylene and propylene. The results are shown in Table 1. It is clear that unless a solution containing magnesium chloride and a phosphorus compound is used, the copolymerization activity is low and the random copolymerization property is also poor. Comparative Example 3 When copolymerizing ethylene and propylene, instead of using a solution containing magnesium chloride and 2-ethylhexyl (di-2-ethylhexyl) phosphine oxide, 2-ethylhexyl (di-2-ethylhexyl) phosphine oxide was used.
-ethylhexyloxy)phosphine oxide
The same procedure as in Example 3 was carried out except that 10 ml of n-hexane solution containing 2.8 mmol was used. No copolymer was obtained at all.

【table】

[Table] Example 10 Dry n-hexane 2 was placed in an autoclave having an internal volume of 3. A mixture of 2 parts ethylene, 8 parts propylene, and 0.2 parts hydrogen was continuously supplied to the autoclave while maintaining the pressure at 5 kg/ ^cm2 . Keep the internal temperature of this autoclave at 30℃ and 0.5mol of triisobutylaluminum/hexane solution 10
ml (5 mmol of Al) was added using a pressure pump. Next, 1 g (10.5 mmol) of anhydrous magnesium chloride
2-ethylhexyl(di-2-ethylhexyloxy)phosphine oxide 19.3ml (42mmol)
1.1 ml (10 mmol) of titanium tetrachloride in a solution dissolved in
and then add n-hexane to bring the total volume to 100%.
diluted to ml. 3.5 ml (0.35 mmol of Ti) of this solution was added to the autoclave using a pressure pump to initiate polymerization.
Simultaneously with the initiation of polymerization, an n-hexane solution containing 7 ml of 5-ethylidene-2-norbornene was continuously supplied using a pressure pump. During the copolymerization reaction, the internal temperature of the autoclave was controlled at 35°C (by cooling the autoclave with an external jacket). After carrying out the copolymerization reaction for 30 minutes, a small amount of methanol was added to stop the polymerization. No gel formation was observed in the solution after copolymerization. A small amount of anti-aging agent and a small amount of dispersion liquid were added, and after adding 1 part of water and stirring well, a rubber elastic copolymer was obtained by steam stripping. The yield of copolymer is 132
g, propylene content in the copolymer is 43 wt%, Mooney viscosity 44, random index RI = 0,
The yoso value was 11.

[Brief explanation of the drawing]

FIG. 1 shows a flowchart representing the catalyst preparation process of the present invention. FIG. 2 shows an infrared absorption spectrum of a copolymer for determining a random index.

Claims (1)

[Claims] 1. In producing a rubbery copolymer by copolymerizing ethylene and α-olefin or ethylene, α-olefin and non-conjugated diene, (A) a hydrocarbon solvent-soluble titanium compound; B) General formula [Formula] (where R ₁ , R ₂ , R ₃ are the same or different hydrocarbon residues or halogenated hydrocarbon residues having 1 to 20 carbon atoms, n ₁ , n ₂ , n ₃
represents 0 or 1. ) A method for producing an olefin copolymer rubber, characterized by using a catalyst consisting of magnesium halide, which is a phosphorus compound represented by (a), and which is solubilized in a hydrocarbon or a halogenated hydrocarbon, and (c) an organoaluminum compound.