JPH05178930A - Production of alpha-olefin/fluorovinyl ether copolymer - Google Patents

Abstract

PURPOSE:To provide the title copolymer at improved efficiency without decreasing the polymerization activity so much by copolymerizing a polyolefin obtained by prepolymerizing an alpha-olefin with an alpha-olefin and a fluorovinyl ether in the presence of a specified catalyst. CONSTITUTION:An alpha-olefin is prepolymerized at -20 to 100 deg.C under atmospheric pressure to 5kg/cm<2>G in the presence of a catalyst mainly consisting of a Ti compound in an amount to give an Al to Ti molar ratio of 1-100 and an organoaluminum compound to obtain 1-100g, per g of the Ti compound, of a polyolefin. An alpha-olefin and a fluorovinyl ether are copolymerized in the presence of this polyolefin in a fluorovinyl ether to alpha-olefin volume ratio of 0.1-5.0 at 0-100 deg.C.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a copolymer of propylene and fluorovinyl ether, and more particularly to a method for efficiently obtaining a copolymer of α-olefin and fluorovinyl ether by using a Ziegler type catalyst. Is.

[0002]

2. Description of the Related Art Copolymers of .alpha.-olefin-fluorine-containing compounds are materials having excellent properties such as ethylene-tetrafluoroethylene copolymers, chemical resistance, heat resistance and electrical properties. It is known. In addition, ethylene-
It is also known that the polymer obtained by copolymerizing tetrafluoroethylene with fluorovinyl ether has further improved physical properties.

Conventionally, as a method for producing such a fluorine-containing copolymer, it has been general to carry out a fluorocarbon initiator as a medium and a radical initiator such as an organic peroxide.
On the other hand, for the production of polyolefin, a production method using a Ziegler type catalyst containing a titanium compound and an organoaluminum compound as main components is widely practiced industrially.

[0004]

In view of the above-mentioned prior art, the present inventors would like to carry out the copolymerization of α-olefin and a fluorine-containing compound in an existing polyolefin production facility using a Ziegler type catalyst. Considering that it may be an economically superior production method, in particular, the inventors have earnestly studied to carry out the copolymerization of α-olefin and fluorovinyl ether using a Ziegler type catalyst. As a result, the Ziegler-type catalyst system was first polymerized with a small amount of α-olefin and then α-olefin.
The present invention has been completed by finding that copolymerization of an olefin and a fluorovinyl ether enables efficient polymerization with less decrease in polymerization activity.

[0005]

According to the present invention, (A)
In the presence of a catalyst mainly composed of a titanium compound and (B) an organoaluminum compound, α-olefin is first prepolymerized to produce 1 to 100 g of polyolefin per unit g of the component (A), and then, Provided is a method for producing an α-olefin-fluorovinyl ether copolymer, which comprises copolymerizing an α-olefin with a fluorovinyl ether.

As the titanium compound (A) which is the catalyst component used in the present invention, a compound known to be used as a main component of a Ziegler type catalyst for the polymerization of α-olefin is adopted without any limitation. Especially titanium, magnesium,
In addition, a titanium compound containing halogen and a high catalytic activity is preferable. Such a titanium compound having a high catalytic activity is obtained by supporting a titanium halide, particularly titanium tetrachloride, on various magnesium compounds. As a method for producing this catalyst, a known method is adopted without any limitation. For example, JP-A-56-155206 and JP-A-56-13.
6806, 57-34103, 58-8706, 58-83006, 58-138708, 58-1.
83709, 59-206408, 59-2193.
11, the same 60-81208, the same 60-81209, the same 6
0-186508, 60-192708, 61-2
11309, 61-271304, 62-1520
9, the same 62-11706, the same 62-72702, the same 62
The method shown in −104810 and the like is adopted. Specifically, for example, a method of co-milling titanium tetrachloride with a magnesium compound such as magnesium chloride, a titanium halide and a magnesium compound in the presence of an electron donor such as alcohol, ether, ester, ketone, or aldehyde. Examples thereof include a method of co-grinding or a method of bringing a titanium halide, a magnesium compound and an electron donor into contact with each other in a solvent. Further, as such a titanium compound, in addition to the above-mentioned supported catalyst, known α, β, γ, or δ-titanium trichloride is also preferably used. A method for adjusting these titanium compounds is described in, for example, JP-A-47-3447.
No. 8, gazette 50-126590, and gazette 50-11439.
4, the same 50-93888, the same 50-12309, the same 50
-74594, 50-104191, 50-984
89, 51-136625, 52-30888, 52-35283 and the like.

As the organoaluminum compound (B) which is another catalyst component used in the present invention, a compound known to be used as a main component of a Ziegler type catalyst for the polymerization of olefins can be adopted without any limitation. .. For example,
Trialkyl aluminums such as trimethyl aluminum, triethyl aluminum, tri-n propyl aluminum, tri-n butyl aluminum, tri-i butyl aluminum, tri-n-hexyl aluminum, tri-n octyl aluminum, and tri-n decyl aluminum; diethyl Diethyl aluminum monohalides such as aluminum monochloride; methyl aluminum sesquichloride, ethyl aluminum sesquichloride,
Examples thereof include alkyl aluminum halides such as ethyl aluminum dichloride. In addition, alkoxy aluminums such as monoethoxy diethyl aluminum and diethoxy monoethyl aluminum can be used. Of these, triethylaluminum is most preferable.

Further, as another catalyst component used in the present invention, in addition to the above-mentioned titanium compound (A) and organoaluminum compound (B), an electron donor known to be used as a catalyst for olefin polymerization is used. You can also As such an electron donor, known compounds such as alcohols, ketones, aldehydes, esters, ethers, amines, amides, nitrites, and organic silicon compounds, organic phosphorus compounds and organic sulfur compounds can be used.

In the production method of the present invention, 1 to 100 g, preferably 1 to 50, per unit g of the titanium compound (A) as a catalyst component is prepared by first prepolymerizing α-olefin.
The desired α-
It is extremely important for efficiently obtaining an olefin-fluorovinyl ether copolymer. That is, α as above
The amount of the polyolefin produced without preliminarily polymerizing the olefin or by prepolymerizing the titanium compound (A)
When the amount is less than 0.1 g per 1 g, the polymerization activity in the following copolymerization of α-olefin and fluorovinyl ether is significantly reduced, which is not preferable. Further, when the amount of the prepolymerized polyolefin is 100 g or more,
The finally obtained α-olefin-fluorovinyl ether copolymer is not preferable because the properties of the α-olefin-α-olefin / fluorovinyl ether block copolymer become strong.

The types of α-olefin used in the prepolymerization of the present invention include, for example, ethylene, propylene, 1
-Butene, 1-hexene, 1-octene, 3-methyl-
1-butene, 4-methyl-1-pentene, styrene and the like can be used alone or in combination.

As the prepolymerization method in the present invention, it is usually preferable to apply a slurry polymerization method, and a saturated aliphatic hydrocarbon such as hexane, heptane, shiphexane, benzene, or toluene, or an aromatic hydrocarbon alone is used as a solvent. , Or a mixed solution thereof can be used.

The catalyst used in this prepolymerization step has an organoaluminum compound content of 1 to 100, preferably 2 to 20, in terms of Al / Ti (molar ratio) with respect to Ti atoms in the titanium compound.

The temperature in the prepolymerization is -20 to
A temperature of 100 ° C., particularly 0 to 60 ° C., is preferable, and the prepolymerization time may be appropriately determined from the temperature and the amount of prepolymerization.
The pressure in the prepolymerization is not particularly limited,
Generally, the atmospheric pressure is about 5 kg / cm ² G. The prepolymerization may be carried out batchwise, semi-batchly or continuously.
After completion of the prepolymerization, it is preferable to wash with a saturated aliphatic hydrocarbon or aromatic hydrocarbon such as hexane, heptane, shiphexane, benzene, and toluene alone or with a mixed solvent thereof, and the washing frequency is usually 5 ~
Six times is preferable.

Next, in the production method of the present invention, after the above-mentioned prepolymerization, main polymerization is carried out by copolymerizing α-olefin-fluorovinyl ether. The main polymerization of the present invention is carried out in the presence of the titanium-containing polyolefin organoaluminum compound obtained by the above preliminary polymerization. The amount of the organic aluminum compound used is 1 / Al (molar ratio) with respect to the titanium atom in the titanium-containing polyolefin.
1000 is preferably 5-500. Further, also in the main polymerization, an electron donor can be optionally used in the catalyst system as in the prepolymerization.

In the main polymerization of the present invention, the fluorovinyl ether to be copolymerized with the α-olefin is represented by the following formula: CF ₂ ═CFO (CH ₂ ) _m C _n F ₁ H _{(2n + 1-l)} in m, n is an integer of 0, l is not particularly limited as long as it is a polymerizable compound represented by the integer) of 0 to 2n + 1, ₂ in particular the following formula _{CF 2 = CFOCH C n F l} H (2n _{+ 1-l)} (n in the formula, l is fluoroalkyl vinyl ether compounds represented by the same) as described above preferably, for example, CF ₂ -
_{CFOCH 3, CF 2 -CFOCH 2 F} , CF 2 -CF
OCH ₂ CF ₃ , CF ₂ -CFOCH ₂ CF ₂ H, CF
_{2 -CFOCH 2 CF 2 CF 3,} CF 2 -CFOCH 2
_{CF 2 CF 2 H, CF 2} -CFOCH 2 CF 2 CF 2 C
_{F 3, CF 2 -CFOCH 2 CF} 2 CF 2 CF 2 H, C
_{F 2 -CFOCH 2 CF 2 CF 2} CF 2 CF 3, CF 2
_{-CFOCH 2 CF 2 CF 2 CF 2} CF 2 H, and the like, generally are _{C 2 F 2 = CFOCH 2 C} 2 F 5 is preferably used.

In the main polymerization of the present invention, the volume ratio of α-olefin and fluorovinyl ether to be subjected to copolymerization is fluorovinyl ether / α-olefin (vol
%) In the range of 0.1 to 5.0, preferably 0.5 to 3.0. That is, if the volume ratio is less than 0.1, the content of fluorovinyl ether in the obtained copolymer will be too small, and if it exceeds 5.0, the polymerization activity will be significantly reduced, which is not preferable. In the case of copolymerizing propylene and fluorovinyl ether, not only propylene alone but also propylene and other α-olefins such as ethylene, 1-butene, 3-methyl-1-butene, 4-methyl-1- 10 penten, 1-hexene, etc.
It is possible to mix up to mol%.

In the main polymerization of the present invention, the molar ratio of titanium atom as the catalyst component and fluorovinyl ether as the raw material is fluorovinyl ether / Ti (mol
/ Mol) 100-5000, especially 500-3000
It is preferable to maintain That is, this molar ratio is 100
If it is smaller, the polymerization activity will be high, but the content of fluorovinyl ether in the copolymer will be low, and if it is larger than 10,000, the activity will be significantly reduced, such being undesirable.

The conditions for the main polymerization are not particularly limited as long as the effects of the present invention are observed, but generally the polymerization temperature is 0 to 100 ° C., preferably 20 to 80, and hydrogen is coexistent as a molecular weight regulator. You can also Also,
As the polymerization method for the main polymerization, for example, any method such as slurry polymerization using a propylene monomer as a medium, solution polymerization, or gas phase polymerization may be used. The polymerization method may be a batch method, a semi-batch method, or a continuous method, and the polymerization may be carried out in two or more stages under different conditions.

After completion of the main polymerization, propylene can be evaporated from the polymerization system to obtain a particulate polymer. Further, in order to purify the polymer, known washing with hydrocarbon or the like can be performed.

[0020]

[Effects] According to the present invention, as is apparent from the examples below, α-olefin-
A fluorovinyl ether copolymer can be efficiently obtained.

[0021]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

The methods for measuring the physical properties of the polymers obtained in the following Examples and Comparative Examples are as follows.

(1) Melt pool rate (abbreviated as MFI) According to ASTM D 1238.

(2) Melting point (abbreviated as T _m ) A sample of 230 was prepared by DSC-200 manufactured by Seiko Denshi Kogyo.
Hold at 10 ℃ for 10 minutes, cool to 115 ℃,
Minute isothermal crystallization was performed, and after cooling to 50 ° C., the temperature was raised at 10 ° C./min for measurement.

(3) Polymerization activity It was determined by the polymer yield per unit g of the titanium compound (A) used in the main polymerization.

That is, the polymerization activity is a value expressed by g-polymer / g-cat.

(4) Fluorovinyl ether content It was calculated from the melting point of the copolymer.

That is,

[0029]

[Equation 1]

[0030] Here, T _m: copolymer of melting point T _m ^0: Homo PP in _{T m (164 + 273K) R} : 8.314J / mol ΔHu: 3696J / mol (5) bulk density obtained when the T _m ⁰ According to ASTM D 1895.

(6) Particle size distribution Opening 75, 125, 250, 355, 500, 71
The polymer was loaded into a 0, 1180 μm sieve, and classified on a sieve shaker for 10 minutes.

Example 1 [Preparation of Titanium Compound] The titanium compound was prepared according to the method of Example 1 described in JP-A-62-104810. That is, 100 g of aluminum trichloride (anhydrous) and 29 g of magnesium hydroxide were reacted with each other by pulverizing them at 250 ° C. for 3 hours in a vibration mill. After completion of heating, the mixture was cooled in a nitrogen stream to obtain a solid product (I).

Purified decane 1 in a glass flask
5 ml, solid product (I) 2.5 g, orthotitanic acid n
-Butyl 8.5 g, 2-ethyl-1-hexanol 9.
8 g were mixed and heated to 130 ° C. for 1.5 hours with stirring to dissolve them to obtain a uniform solution. The solution was heated to 70 ° C., 1.8 g of ethyl p-toluate was added and reacted for 1 hour, 26 g of silicon tetrachloride was added dropwise over 2 hours with stirring to precipitate a solid, and the mixture was further stirred at 70 ° C. for 1 hour. did. The solid was separated from the solution and washed with purified hexane to obtain a solid product (II).

To the total amount of the solid product (II), 1.5 g of diisobutyl phthalate was added together with 30 ml of 1,2-dichloroethane and 30 ml of titanium tetrachloride, and the mixture was reacted at 100 ° C. for 2 hours while stirring, and then at the same temperature. The liquid phase part was removed by decantation, 1,2-dichloroethane (30 ml), titanium tetrachloride (30 ml) and diisobutyl phthalate (1.5 g) were added again, and the mixture was reacted at 100 ° C. for 2 hours with stirring, and then the solid part was filtered by heat filtration. Was collected, washed with purified hexane, and dried under reduced pressure at 25 ° C. for 1 hour to obtain a solid product (I
II) got

The solid product (III) was spherical and had an average particle size of 15 μm, and its particle size distribution was extremely narrow. This solid product (III) was used as a solid Ti catalyst component.

The composition of this solid Ti catalyst component was analyzed as follows: Ti 3.0% by weight (hereinafter referred to as%), Cl 5
With 6.2%, Mg 17.6%, Al 1.7%, diisobutyl phthalate 20.1%, butoxy group 1.1%, 2-ethylhexyloxy group 0.2%, p-ethyl toluate 0.1%. there were.

[Preliminary Polymerization] Purified heptane (200 ml), triethylaluminum (50 mmol), and diphenyldimethoxysilane (1) were placed in a 1 l autoclave substituted with N _2.
0 mmol, and solid Ti catalyst component 5 in terms of Ti atom
After charging mmol, propylene was added to solid Ti catalyst component 1
It was continuously introduced into the reactor for 1 hour so that the amount became 5 g relative to g, and prepolymerization was performed. The temperature during this period was kept at 15 ° C. After 1 hour, the introduction of propylene was stopped and the inside of the reactor was replaced with N ₂ . The solid portion of the resulting slurry was washed 6 times with purified heptane.

[Main Polymerization] Content of 2 liters subjected to N ₂ substitution
- the autoclave, liquid propylene 500 ml, liquid propane 500 ml, and charged with hydrogen gas 400 ml, triethyl aluminum 6.58 mmol, was charged with cyclohexylmethyldimethoxysilane 0.658 mmol, further fluorovinyl ether C ₂ F ₅ CH ₂ O
6.6 ml of CF = CF ₂ (hereinafter abbreviated as FVE)
After charging, the internal temperature of the autoclave was raised to 60 ° C., 0.06 g of solid components were added to start polymerization, and the mixture was heated at 60 ° C. for 1 hour.
Polymerization was carried out for 20 minutes.

After completion of the polymerization, after purging unreacted propylene and propane, 88 g of a white granular polymer was obtained.
The polymerization activity at this time was 1460 g-polymer / g-ca.
The result was shown in Table 1.

Examples 2 and 3 In the main polymerization of Example 1, the charging amount of fluorovinyl ether (FVE) was 3.3 ml (Example 2), 10 m.
The same operation as in Example 1 was carried out except that 1 (Example 3) was used. The results are shown in Table 1.

Examples 4 and 5 In the main polymerization of Example 1, the same operation as in Example 1 was carried out except that the polymerization temperature was 70 ° C. (Example 4) and 80 ° C. (Example 5). It was The results are shown in Table 1.

Example 6 In the main polymerization of Example 1, without using liquid propane, 1000 ml of liquid propylene was used, the amount of fluorovinyl ether charged was 3.3 ml, and the amount of solid Ti component was 0.02 g.
The same operation as in Example 1 was performed except for the above. The results are shown in Table 1.

Example 7 [Preparation of Titanium Compound] The titanium compound was prepared according to the method of Example 1 described in JP-A-62-111706. That is, a glass three-necked flask (with a thermometer and a stirrer) with an internal volume of 500 ml that was replaced with nitrogen.
To this is added 50 ml of purified heptane, 50 ml of titanium tetrabutoxide, 7.0 g of anhydrous magnesium chloride. Then, the temperature of the flask was raised to 90 ° C., and magnesium chloride was completely dissolved over 2 hours. The flask is then cooled to 40 ° C. and 10 ml of methylhydrogenpolysiloxane are added to give magnesium chloride,
A titanium tetrabutoxide complex was deposited. This was washed with purified heptane to give an off-white solid.

50 ml of a heptane slurry containing 10 g of the precipitated solid obtained above was introduced into a glass three-necked flask (equipped with a thermometer and a stirrer) having an inner volume of 300 ml which had been purged with nitrogen. Then, 20 ml of a heptane solution containing 5.8 ml of silicon tetrachloride was added at room temperature over 30 minutes, and a further 30 minutes was added.
The reaction was carried out at 0 ° C for 45 minutes. The mixture was further reacted at 90 ° C. for 1.5 hours, and after completion of the reaction, it was washed with purified heptane. Then, 50 ml of a heptane solution containing 1.5 ml of diheptyl phthalate was added and reacted at 50 ° C. for 2 hours, then washed with purified heptane, further 25 ml of titanium tetrachloride was added and reacted at 90 ° C. for 2 hours. This was washed with purified heptane to obtain a solid Ti catalyst component. The titanium content in the solid Ti catalyst component was 3.04% by weight.

Then, prepolymerization and main polymerization were carried out in the same manner as in Example 1 using the catalyst component prepared above. The results are shown in Table 1.

Example 8 [Preparation of titanium compound] The titanium component was prepared according to the method of Example 1 described in JP-A-58-83006. That is, 0.95 g of anhydrous magnesium chloride
12 ml of (10 mmol), 10 ml of decane, and 4.7 ml (30 mmol) of 2-ethylhexyl alcohol.
After heating and stirring at 5 ° C. for 2 hours, 0.55 g (3.75 mmol) of phthalic anhydride was added to this solution, and the temperature was 125 ° C.
The mixture was further stirred and mixed for 1 hour to form a uniform solution. After cooling to room temperature, the whole amount was dropped into 40 ml (0.36 mol) of titanium tetrachloride kept at 120 ° C. over 1 hour. After the completion of charging, the temperature of this mixed solution was raised to 110 ° C. over 2 hours, and when it reached 110 ° C., 0.54 ml (2.5 mmol) of diisophthalate was added, and the temperature was kept the same for 2 hours. And kept under stirring. After the completion of the reaction for 2 hours, a solid portion was collected by hot filtration, and the solid portion was resuspended in 200 mm of TiCl ₄ and then again 11
A heating reaction was carried out at 0 ° C. for 2 hours. After the reaction was completed, the solid part was collected again by hot filtration, and with decane and hexane,
It was thoroughly washed until no free titanium compound was detected in the washing liquid. The solid Ti catalyst component prepared by the above manufacturing method was stored as a heptane slurry. Solid Ti
The composition of the catalyst components was 2.1% by weight titanium, 57% by weight chlorine, 18.0% by weight magnesium, and 21.9% by weight diisobutyl phthalate.

Hereinafter, using the above-prepared catalyst component,
Prepolymerization and main polymerization were carried out in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 Example 1 except that the prepolymerization of Example 1 was not performed.
The same operation was performed. The results are shown in Table 1.

Comparative Examples 2 and 3 In the main polymerization of Example 1, the amount of fluorovinyl ether (FVE) charged was 0.3 ml (Comparative Example 2), 20 m.
1 (Comparative Example 3) The same operation as in Example 1 was performed except that the charging was performed. The results are shown in Table 1.

[0050]

[Table 1]

[0051]

[Table 2]

Examples 9 and 10 In Example 1, CF ₂ ═CFOCH is used instead of FVE.
₂ CF ₃ (Example 9), CF ₂ ═CFOCH ₂ (C
Example ₂ was carried out under the same conditions as in Example 1 except that F ₂ ) ₂ CF ₃ (Example 10) was used. The obtained results were that the polymer yields were 79 g and 71 g, respectively, and the polymerization activities at this time were 1320 g-polymer / g-cat and 1180 g-polymer / g-cat, respectively, and the content of fluorovinyl ether was 0.99. 0.98 mol%, MI 3.7 and 4.9 g / 10 min, and bulk specific densities of both 0.9.
The particle size was 45 g / cc and the particle size was 0.5 wt% or less.

Claims (1)

[Claims] 1. An α-olefin is first prepolymerized in the presence of a catalyst having (A) a titanium compound and (B) an organoaluminum compound as main components, and 1 to 100 g per unit g of the (A) component. A method for producing an α-olefin-fluorovinyl ether copolymer, which comprises copolymerizing an α-olefin and a fluorovinyl ether after producing a polyolefin.