JP2002060450A - Method for manufacturing propylene-ethylene block copolymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a propylene-ethylene block copolymer wherein the propylene-ethylene block copolymer containing less gel or less fish eyes is manufactured in a state free of stickiness yet high in flowability with the generation of clotting polymer or adhering polymer suppressed. SOLUTION: The method comprises two stages which are the 1st stage (1) wherein a crystalline propylene polymer is manufactured in liquid propylene or in the gas state and the 2nd stage (2) wherein a rubber-like copolymer is manufactured in the gas state, where the two stages are processed successively in the presence of a catalyst comprising a solid catalytic component (A) essentially containing titanium, magnesium, a halogen, and an electron donating matter, an organic aluminum compound (B). To the transfer section wherefrom the polymer is to be transferred to the 2nd stage, and to a 2nd stage polymerization tank, an electron donating compound (C) is added so that the 2nd stage polymerization activity becomes 0.3-0.95 times the activity without the compound (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a propylene-ethylene block copolymer.
More specifically, it has high rigidity, high impact resistance and gel,
Propylene-ethylene block copolymer that reduces fish eyes and reduces the production of lumped polymer and adherent polymer, making it possible to produce a propylene-ethylene block polymer in a non-sticky and fluid state. And a method for producing the same.

[0002]

2. Description of the Related Art Crystalline polypropylene has excellent rigidity and heat resistance, but has the problem of low impact strength, especially at low temperatures. As a method for improving this point, a method of stepwise polymerizing propylene with ethylene or another olefin to form a block copolymer is already known (for example, Japanese Patent Publication No.
No. 3-11230).

However, when the multi-stage polymerization is carried out by a continuous polymerization method, the distribution of the polymerization time of the catalyst component (residence time in the polymerization tank) occurs in the first-stage polymerization tank, and the catalyst component is discharged from the first-stage polymerization tank in a relatively short time. When the discharged particles (short-path particles) enter the second-stage polymerization tank, there is a problem that particles having a high content of the propylene-ethylene copolymer are generated. Such particles do not disperse even by kneading, cause gels and fish eyes, impair the appearance of the product, and lower the mechanical strength.

In order to increase the impact resistance, it is effective to increase the proportion of the copolymer in the second stage. However, when the proportion of the copolymer is increased, even ordinary particles which are not short-passed can be used. , It easily adheres to the polymerization tank wall, etc.
It may interfere with driving. In addition, the stickiness of the particles increases, and the fluidity of the generated powder deteriorates, which hinders extraction and transfer from the polymerization tank.

As a method for reducing the formation of gels and fish eyes caused by such short-path particles and reducing the adhesion of particles having a high copolymer content, a method of adding an electron-donating compound to the second-stage polymerization step is used. Is known, and the function of the electron donating compound is estimated as follows.

That is, the electron-donating compound selectively acts on a polymerization active site relatively near the surface of the polymer particle,
Although these active points are deactivated, the short-pass particles have a small particle size and are easily deactivated completely, so that the particles are selectively deactivated even at an added amount where the particles are not completely deactivated. Because the active sites on the surface are selectively deactivated, the copolymer in the second stage polymerization is formed inside the particles, and even if the copolymer content is high, the increase in surface adhesion is relatively suppressed. Conceivable.

[0007] The method of adding the electron donating compound to the second-stage polymerization step is generally a method of adding the polymer formed in the first-stage polymerization tank during the transfer to the second-stage polymerization tank;
There are two methods of adding to the second stage polymerization tank itself.

In the former method, the electron-donating compound is added to a transfer pipe for transferring a polymer from the first-stage polymerization tank to the second-stage polymerization tank. There is a method in which a separate reaction tank is provided in between and a method of adding the reaction tank is used. In these methods, all particles come into contact with the electron-donating compound before being subjected to copolymerization in the second-stage polymerization tank, so that the effect of reducing adhesion and gel is great. But,
Since the deactivating effect is exhibited even with a relatively small amount, there is a problem that it is difficult to control the required addition amount while maintaining the activity in the second-stage polymerization tank at an appropriate level.

For the purpose of adding the electron donating compound little by little, a method of adding the compound by diluting it with a solvent or the like which does not affect the catalytic activity has been adopted. The diluent introduced into the second polymerization tank together with the electron-donating compound accompanies the monomer recovery system and the product powder, which increases the load on the equipment, and is not a preferable method.

In the method of adding to the second-stage polymerization tank,
In addition to adding the electron-donating compound by providing a dedicated supply port in the second-stage polymerization tank, there are a method of entraining with an agent such as hydrogen, a method of entraining with a circulating monomer, and the like.

In these methods, it is relatively easy to control the amount of the electron-donating compound added in view of the activity in the second-stage polymerization tank. Depending on the positional relationship between the electron-donating compound and the supply point, particles that are insufficiently in contact with the electron-donating compound may be generated, and these may grow to adhere and form a bulk polymer.

Further, by increasing the amount of the electron-donating compound added, it is possible to suppress the adhesion of the polymer and the formation of the bulk polymer. However, in this method, the polymerization activity is sacrificed, and the required copolymer content is reduced. It becomes difficult to do.

[0013]

SUMMARY OF THE INVENTION The present invention is directed to a propylene-ethylene block polymer having high rigidity and high impact strength, and having less gel and fish eyes, by reducing the formation of a bulk polymer and an adherent polymer, It is an object of the present invention to provide a method for producing a propylene-ethylene block copolymer, which can be produced in a state without good fluidity.

[0014]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, when adding an electron donating compound to the second polymerization step, the first polymerization was carried out after the second polymerization. The present inventors have found that the above problem can be solved by adding an electron-donating compound both during the transfer of the polymer to the polymerization and in the second-stage polymerization tank, and completed the present invention.

That is, the present invention provides a propylene-ethylene block copolymer by continuously performing the following first-stage polymerization and second-stage polymerization in the presence of a catalyst comprising the following components (A) and (B): In the method for producing a polymer, the following component (C) is added to both the polymer transfer section from the first-stage polymerization to the second-stage polymerization and the second-stage polymerization tank, and polymerization is performed. A method for producing a propylene-ethylene block copolymer, characterized in that the addition amount is adjusted so that the activity of the second-stage polymerization is 0.3 to 0.95 times that of the case where the component (C) is not added. To provide. (A) a solid catalyst component containing titanium, magnesium, halogen and an electron donor as essential components (B) an organoaluminum compound (C) an electron donating compound (1) first-stage polymerization propylene alone or a mixture of propylene and ethylene, A step of polymerizing in one or more polymerization tanks in liquid propylene or in a gaseous phase to produce a crystalline propylene polymer; (2) second-stage polymerization A step of producing a rubbery copolymer by polymerizing in one or more polymerization tanks.

[0016] The present invention also relates to the first stage polymerization to the second stage polymerization.
The amount of component (C) added to the polymer transfer section
C₁, The amount of component (C) added to the second-stage polymerization tank_TwoTo be
When C ₁And C_TwoSatisfies the following equation (1)
Provided is a method for producing a len-ethylene block copolymer.
Things.

0.05 ≦ C ₁ / (C ₁ + C ₂ ) ≦ 0.8 (1) Further, the present invention keeps C ₁ constant with respect to the amount of the component B and changes C ₂ . The method for producing the propylene-ethylene block copolymer described above, wherein the effect of adding the component C is controlled, and the supply path of the component C is changed from the first-stage polymerization to the second-stage polymerization of the component (C) from the component C supply device. Even when the addition amount of the component (C) is changed by branching into a flow channel for adding the polymer to the transfer section of the stage polymerization and a flow channel for adding the component (C) to the second polymerization tank, the ratio of ₁ and C ₂ to be always kept constant, the above propylene - there is provided a method for producing ethylene block copolymer.

[0018]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a propylene-ethylene block copolymer is produced by polymerizing propylene and ethylene using a catalyst containing titanium, magnesium, halogen and an electron donor.

<Catalyst> Component (A) The component (A) used in the present invention is a solid catalyst component for stereoregular polymerization of α-olefin, which contains titanium, magnesium, halogen and an electron donor as essential components. It is. Here, "containing as an essential component" means that in addition to the four components listed, other purposeful elements may be contained, and each of these elements is present as a purposeful arbitrary compound. And that these elements may be present as bonded to each other.

The solid components containing titanium, magnesium and halogen are known per se. For example, JP-A-53-45688, JP-A-54-3894, and JP-A-54-3894.
Nos. 31092, 54-39483, 54-945
No. 91, No. 54-118484, No. 54-13158
No. 9, No. 55-75411, No. 55-90510,
No. 55-90511, No. 55-127405, No. 5
5-147507, 55-155003, 56
-18609, 56-70005, 56-72
No. 001, No. 56-86905, No. 56-90807
Nos. 56-155206, 57-3803, 57-34103, 57-92007, 57-
No. 121003, No. 58-5309, No. 58-531
No. 0, No. 58-5311, No. 58-8706, No. 5
8-27732, 58-32604, 58-3
No. 2605, No. 58-67703, No. 58-1172
No. 06, No. 58-127708, No. 58-18370
No. 8, No. 58-183709, No. 59-149905
Nos. 59-149906 and 63-108008
Nos. 63-264607 and 63-264608
JP-A-1-79203, JP-A-1-98603, JP-A-7-258328, JP-A-8-269125, and JP-A-11-21
309 are used.

The magnesium compound used as a magnesium source in the present invention includes metal magnesium, magnesium dihalide, dialkoxymagnesium, alkoxymagnesium halide, magnesium oxyhalide, dialkylmagnesium, alkylmagnesium halide, magnesium oxide, magnesium hydroxide. And magnesium carboxylate. Among these, Mg (OR ¹ ) _{2 -m} X _m such as magnesium dihalide and dialkoxy magnesium (where R ¹ is a hydrocarbon group, preferably having about 1 to 10 carbon atoms, and X is And m is 0 ≦ m ≦ 2).

Further, as a titanium compound serving as a titanium source,
Is represented by the general formula Ti (OR^Two)_4-nX_n(Where R^TwoIs hydrocarbon
A basic group, preferably having about 1 to 10 carbon atoms;
Represents a halogen, and p is 0 ≦ n ≦ 4. )
Compounds. As a specific example, TiCl_Four,
TiBr_Four, TiI_Four, Ti (OC_TwoH_Five) Cl_Three, Ti
(OC_TwoH_Five)_TwoCl_Two, Ti (OC_TwoH_Five)_ThreeCl, Ti
(OiC_ThreeH₇) Cl_Three, Ti (On-C_FourH₉) C
l_Three, Ti (On-C_FourH₉)_TwoCl_Two, Ti (OC
_TwoH_Five) Br_Three, Ti (OC_TwoH_Five) (On-C)_FourH₉)_TwoC
1, Ti (On-C_FourH₉) _ThreeCl, Ti (OC₆H_Five)
Cl_Three, Ti (OiC_FourH₉)_TwoCl_Two, Ti (OC_FiveH
₁₁) Cl_Three, Ti (OC₆H₁₃) Cl_Three, Ti (OC
_TwoH_Five)_Four, Ti (On-C _ThreeH₇)_Four , Ti (On-
C_FourH₉)_Four, Ti (OiC_FourH₉)_Four, Ti (On-
C₆H₁₃)_Four, Ti (On-C₈H₁₇)_Four, Ti (OCH
_TwoCH (C_TwoH_Five) C_FourH₉)_FourAnd the like.

Also, TiX '_Four(Where X 'is a halogen
It is. ) By reacting with an electron donor described later
The compound can also be used as a titanium source. like that
Specific examples of the molecular compound include TiCl_Four・ CH_ThreeCOC
_TwoH_Five, TiCl_Four・ CH_ThreeCO _TwoC_TwoH_Five, TiCl_Four・ C₆
H_FiveNO_Two, TiCl_Four・ CH_ThreeCOCl, TiCl_Four・ C ₆
H_FiveCOCl, TiCl_Four・ C₆H_FiveCO_TwoC_TwoH_Five, TiC
l_Four・ ClCOC_TwoH_Five, TiCl_Four・ C_FourH_FourO etc.
It is.

Also, TiCl ₃ (including TiCl ₄ reduced with hydrogen, reduced with aluminum metal, reduced with an organometallic compound, etc.), TiB
It is also possible to use titanium compounds such as r ₃ , Ti (OC ₂ H ₅ ) Cl ₂ , TiCl ₂ , dicyclopentadienyltitanium dichloride, and cyclopentadienyltitanium trichloride. Among these titanium compounds, TiC
_{l 4, Ti (OC 4 H} 9) 4, Ti (OC 2 H 5) Cl 3 are preferred.

The halogen is usually supplied from the above-mentioned magnesium and / or titanium halides, but other halogen sources such as AlCl ₃ , A
aluminum halides such as lBr ₃ and AlI ₃ , B
Halides of boron such as Cl ₃ , BBr ₃ , BI ₃ , S
silicon halides such as iCl _4, PCl ₃ , PCl ₅
, A tungsten halide such as WCl ₆ , and a molybdenum halide such as MoCl ₅ . Halogen contained in the catalyst component is fluorine, chlorine,
It may be bromine, iodine or a mixture thereof, with chlorine being particularly preferred.

Examples of the electron donor include oxygen-containing electrons such as alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic acids or inorganic acids, ethers, acid amides, and acid anhydrides. Examples include donors, nitrogen-containing electron donors such as ammonia, amines, nitriles, and isocyanates, and sulfur-containing electron donors such as sulfonic acid esters.

More specifically, (a) methanol, ethanol
Knol, propanol, butanol, pentanol, f
Xanol, octanol, dodecanol, octadeci
Alcohol, benzyl alcohol, phenylethyl alcohol
Carbon such as alcohol and isopropylbenzyl alcohol
Alcohols of the formulas 1 to 18, (b) phenol,
Resole, xylenol, ethylphenol, propyl
Phenol, isopropylphenol, nonylphenol
6 carbon atoms which may have an alkyl group such as
To 25 phenols, (c) acetone, methyl ether
Tyl ketone, methyl isobutyl ketone, acetopheno
C3 to C15 ketones such as benzophenone and benzophenone
, (D) acetaldehyde, propionaldehyde,
Octylaldehyde, benzaldehyde, tolaldehyde
Al, C2 to C15 aldol such as naphthaldehyde
Aldehydes, methyl (form) formate, methyl acetate, ethyl acetate
, Vinyl acetate, propyl acetate, octyl acetate,
Clohexyl, cellosolve acetate, ethyl propionate,
Methyl butyrate, ethyl valerate, ethyl stearate,
Methyl acetate, ethyl dichloroacetate, methyl methacrylate
, Ethyl crotonate, cyclohexanecarboxylate
, Methyl benzoate, ethyl benzoate, propyl benzoate
Butyl, butyl benzoate, octyl benzoate, shik benzoate
Rohexyl, phenyl benzoate, benzyl benzoate, ammonium
Cellosolve benzoate, methyl toluate, toluic acid ethyl
, Amyl toluate, ethyl ethyl benzoate, anise
Methyl acrylate, ethyl anisate, ethyl ethoxybenzoate,
γ-butyrolactone, α-valerolactone, coumarin,
Organic acid monoester such as phthalide or phthalic acid
Diethyl, dibutyl phthalate, diheptyl phthalate,
Diethyl succinate, dibutyl maleate, 1,2-cyclo
Diethyl hexanecarboxylate, ethylene carbonate, norvol
Nandienyl-1,2-dimethylcarboxylate,
Clopropane-1,2-dicarboxylic acid-n-hexyl,
Organic such as diethyl 1,1-cyclobutanedicarboxylate
Organic acid ester having 2 to 20 carbon atoms of acid polyvalent ester
Silicates, such as ethyl silicate and butyl silicate
Inorganic acid esters such as stele, (g) acetyl chloride
Lido, benzoyl chloride, toluic acid chloride, ani
Acid chloride, phthaloyl chloride, phthaloyl isochloride
Which acid halides having 2 to 15 carbon atoms, (thi) methyl
Ether, ethyl ether, isopropyl ether,
Tyl ether, amyl ether, tetrahydrofuran,
Anisole, diphenyl ether, 2,2-dimethyl-
1,3-dimethoxypropane, 2,2-diisopropyl
-1,3-dimethoxypropane, 2,2-diisobutyl
-1,3-dimethoxypropane, 2-isopropyl-2
-Isobutyl-1,3-dimethoxypropane, 2-iso
Propyl-2-s-butyl-1,3-dimethoxypropa
2-t-butyl-2-methyl-1,3-dimethoxy
Propane, 2-t-butyl-2-isopropyl-1,3
-Dimethoxypropane, 2,2-dicyclopentyl-
1,3-dimethoxypropane, 2,2-dicyclohexyl
1,3-dimethoxypropane, 2,2-diphenyl
-1,3-dimethoxypropane, 2,2-dimethyl-
1,3-diethoxypropane, 2,2-diisopropyl
C2-C2 such as -1,3-diethoxypropane
0 ethers, (li) acetic acid amide, benzoic acid amide,
Acid amides such as toluic acid amide;
, Ethylamine, diethylamine, tributylamine
, Piperidine, tribenzylamine, aniline, pyri
Gin, picoline, tetramethylethylenediamine, etc.
Amines, (ル) acetonitrile, benzonitrile,
Nitriles such as lunitrile, (ヲ) 2- (ethoxyme
Tyl) -ethyl benzoate, 2- (t-butoxymethyl)
-Ethyl benzoate, 3-ethoxy-2-phenylpropyi
Ethyl onate, ethyl 3-ethoxypropionate, 3-
Ethyl ethoxy-2-s-butylpropionate, 3-E
Alkyls such as ethyl toxic-2-t-butylpropionate
Coxyester compounds, (W) 2-benzoylbenzoic acid
Ethyl acid, 2- (4'-methylbenzoyl) benzoic acid
Tyl, 2-benzoyl-4,5-dimethylbenzoic acid
Ketoester compounds such as
Methyl phosphate, ethyl benzenesulfonate, p-toluene
Ethyl sulfonate, isopropyl p-toluenesulfonate
N-butyl p-toluenesulfonate, p-toluene
Sulfonic acid esters such as s-butyl sulfonic acid
Kind, (yo) R^Three _pR^Four _qSi (OR^Five)_r(OR⁶)
_4-pqr(Where R ^ThreeAnd R^FourAre the same or different
A branched, cyclic or straight chain having 1 to 20 carbon atoms which may be
A chain hydrocarbon group;^FiveIs a hydrocarbon having 1 to 10 carbon atoms
A radical, R⁶Is a hydrocarbon group having 1 to 4 carbon atoms.
And p, q, and r are respectively 1 ≦ p ≦ 2, 0 ≦ q ≦ 1, 0
≦ r ≦ 2 and p + q + r ≦ 3. )
Organic silicon compounds.

As the solid catalyst component (A), the above-mentioned solid components may be used as they are, or solid catalyst components obtained by contacting with another electron donor may be used.

Two or more of these electron donors can be used. Of these, preferred are organic acid ester compounds, acid halide compounds, ether compounds and organosilicon compounds, and particularly preferred are phthalic acid diester compounds, cellosolve acetate compounds, phthalic dihalide compounds and diether compounds.

The component (A) may be preliminarily polymerized before being subjected to polymerization, if necessary.

Component (B) Component (B) that can be used in the present invention is an organoaluminum compound.

[0032] As specific examples, R ⁷ _3-s AlX s or R ⁸
_3-t Al (OR ⁹ ) _t (where R ⁷ and R ^{8 each} have 1 carbon atom)
And R ⁹ is a hydrocarbon group, X is a halogen, and s and t are 0 ≦ s <3 and 0 <t <3, respectively. ).

Specifically, (a) trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum and tri-n-decylaluminum; Alkyl aluminum halides such as diethylaluminum monochloride, diisobutylaluminum monochloride, ethylaluminum sesquichloride and ethylaluminum dichloride; (c) alkylaluminum hydrides such as diethylaluminum hydride and diisobutylaluminum hydride; (d) diethylaluminum ethoxide and diethylaluminum Examples thereof include alkylaluminum alkoxides such as phenoxide.

These organoaluminum compounds (a) to (d) are combined with other organometallic compounds, for example, R ¹⁰ _3-u Al (O
R ¹¹ ) _u (where R ¹⁰ and R ¹¹ are the same or different and are a hydrocarbon group having 1 to 20 carbon atoms, and u is 0 <
u ≦ 3. ) May be used in combination. For example, a combination of triethylaluminum and diethylaluminum ethoxide, a combination of diethylaluminum monochloride and diethylaluminum ethoxide, a combination of ethylaluminum dichloride and ethylaluminum diethoxide, triethylaluminum and diethylaluminum ethoxide and diethylaluminum monochloride And the like.

The ratio of the organoaluminum compound component (B) to the titanium component in the solid catalyst component (A) is generally Al / Ti = 1 to 1000 mol / mol. / Ti = 10 to 500 mol / mol is used.

In addition to the components (A) and (B), an electron-donating compound can be used, if necessary, as a catalyst component.

Examples of such an electron donating compound include those which can be used as an essential component in the component (A). When such an electron donating compound is used, it may be the same as or different from the compound in the component (A).

Preferred electron-donating compounds are ethers, inorganic acid esters, organic acid esters and organic acid halides, and organosilicon compounds. Particularly preferred are inorganic and organic silicate esters, phthalic esters, cellosolve acetate and It is a phthalic acid halide.

Preferred silicate esters are those represented by the general formula R ¹² _v R ¹³ _w Si (OR ¹⁴ ) _4-vw (where R ¹² is a branched aliphatic carbon having 3 to 20, preferably 4 to 10 carbon atoms). Hydrogen residue, or 5 carbon atoms
20, preferably a cycloaliphatic hydrocarbon residue of 6 to 10, R ¹³ having 1 to 20 carbon atoms, preferably branched or linear aliphatic hydrocarbon residue 1 to 10, R ¹⁴ is a carbon Number 1
10 to 10, preferably 1 to 4 aliphatic hydrocarbon residues
Is an organic silicon compound represented by 0 ≦ v ≦ 3, and w is a number satisfying 0 ≦ w ≦ 3 and v + w ≦ 3). Preferably, R ^{12 in the} above general formula is branched from a carbon atom adjacent to a silicon atom.

Component (C) The electron donating compound to be added to the second stage polymerization is usually an organic compound containing oxygen, nitrogen, phosphorus or sulfur.

Specifically, alcohols, phenols, ketones, aldehydes, acetals, organic acids, acid anhydrides, acid halides, esters, ethers, amines, amides, nitriles, Phosphines,
Examples include phosphylamides, thioethers, thioesters, and organosilicon compounds containing a Si—O—C bond.

More specifically, the following can be mentioned.

Alcohols: methanol, ethanol,
n-propyl alcohol, isopropyl alcohol, n
-Butyl alcohol, sec-butyl alcohol, isobutyl alcohol, t-butyl alcohol, pentyl alcohol, hexyl alcohol, cyclohexyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, Isopropylbenzyl alcohol, ethylene glycol, diethylene glycol, 2,2-dimethyl-
1,3-propanediol, 2,2-diisopropyl-
1,3-propanediol, 2,2-diisobutyl-
1,3-propanediol, 2-isopropyl-2-isobutyl-1,3-propanediol, 2-isopropyl-2-s-butyl-1,3-propanediol, 2-
t-butyl-2-methyl-1,3-propanediol,
2-t-butyl-2-isopropyl-1,3-propanediol, 2,2-dicyclopentyl-1,3-propanediol, 2,2-dicyclohexyl-1,3-propanediol, 2,2-diphenyl- C1-C20 alcohols such as 1,3-propanediol, 2,2-dimethyl-1,3-propanediol and 2,2-diisopropyl-1,3-propanediol.

Phenols: phenol, cresol,
C6 to C25 phenols which may have an alkyl group, such as xylenol, ethylphenol, propylphenol, cumylphenol, nonylphenol and naphthol.

Ketones: C1 to C20 ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone and benzoquinone.

Aldehydes: C2 to C15 aldehydes such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde and naphthaldehyde.

Acetals: Acetals having 3 to 24 carbon atoms, such as dimethyldimethoxymethane, 1,1-dimethoxycyclohexane, and 1,1-dimethoxycyclopentane.

Organic acids: having two or more carboxyl groups such as formic acid, acetic acid, propionic acid, valeric acid, caprylic acid, pivalic acid, acrylic acid, methacrylic acid, monochloroacetic acid, benzoic acid, maleic acid and phthalic acid Good carboxylic acids having 1 to 20 carbon atoms.

Acid anhydrides: Acid anhydrides derived from the above organic acids, including intramolecular condensates and heterogeneous condensates.

Acid halides: Acid halides in which the hydroxyl groups of the above organic acids have been substituted with chlorine, bromine and iodine atoms.

Esters: methyl formate, ethyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl butyrate, ethyl valerate, methyl chloroacetate, methacrylic acid Methyl, dimethyl maleate,
Esters derived from the above alcohols and acids, such as methyl benzoate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, dibutyl phthalate, diisobutyl phthalate, dihexyl phthalate, dioctyl phthalate, methyl carbonate, and ethyl carbonate.

Ethers: dimethyl ether, diethyl ether, dipropyl ether, dibutyl ether, methyl-t-butyl ether, anisole, vinyl methyl ether, vinyl ethyl ether, vinyl n-butyl ether, 1,1-dimethoxyethane, o-dimethoxy Benzene, 2,2-dimethyl-1,3-dimethoxypropane, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isobutyl-1 , 3-
Dimethoxypropane, 2-isopropyl-2-s-butyl-1,3-dimethoxypropane, 2-t-butyl-2
-Methyl-1,3-dimethoxypropane, 2-t-butyl-2-isopropyl-1,3-dimethoxypropane,
2,2-dicyclopentyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2,2-diphenyl-1,3-dimethoxypropane, 2,2-dimethyl-1,3- Ethers derived from said alcohols or phenols, such as diethoxypropane, 2,2-diisopropyl-1,3-diethoxypropane.

Amines: amines having 1 to 21 carbon atoms such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, tetramethylethylenediamine and the like.

Amides: acetic acid amide, benzoic acid amide,
Amides derived from the organic acids and the amines, such as toluic acid amide.

Nitriles: Nitriles having 2 to 10 carbon atoms such as acetonitrile, benzonitrile and tolunitrile.

Phosphines: phosphines such as trimethylphosphine, triethylphosphine and triphenylphosphine.

Phosphylamides: phosphylamides such as hexamethylphosphyltriamide.

Thioethers: Thioethers obtained by substituting oxygen atoms of the above ethers with sulfur atoms.

Thioesters: Thioesters in which the oxygen atoms of the above esters have been replaced by sulfur atoms.

Organosilicon compounds containing Si—O—C bonds: tetramethoxysilane, tetraethoxysilane,
Tetrabutoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxylan, trimethylethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, phenyltrimethoxysilane, γ-chloropropyltri Methoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, propyltriethoxysilane, butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyltriisopropoxy Silane, vinyltributoxysilane, trimethylphenoxysilane, methyltriaryloxysilane, vinyltris (β-methoxy ) Silane, vinyl triacetoxy silane, organic silicon compounds such as dimethyl tetraethoxy disiloxane. Of these, alcohols, ketones and esters are preferred, and particularly preferred are methanol, ethanol, isopropyl alcohol, acetone and methyl acetate.

These electron donating compounds may be used in combination of two or more as necessary. Further, different compounds may be added to the two addition positions.

<Polymerization Step> The polymerization step of the present invention comprises two stages, a first stage polymerization and a second stage polymerization. First-stage polymerization and second-stage polymerization are performed in this order (first-stage polymerization → second-stage polymerization)
Is industrially advantageous.

First Stage Polymerization In the first stage polymerization, propylene alone or a mixture of propylene and ethylene is added in the presence of component (A), component (B) and, if necessary, an electron donating compound. This is a step of producing a crystalline propylene polymer by performing polymerization in the above polymerization tank. In the first-stage polymerization, it is desirable to form a propylene homopolymer or a propylene / ethylene copolymer having an ethylene content of 7% by weight or less in an amount corresponding to 10 to 90% by weight of the total polymerization amount. If the ethylene content in the propylene / ethylene polymer exceeds 7% by weight in the first-stage polymerization, the bulk density of the final copolymer decreases, and the amount of by-product of the low-crystalline polymer greatly increases. On the other hand, when the polymerization ratio is less than the lower limit of the above range, the amount of by-product of the low crystalline polymer also increases.

The polymerization temperature in the first stage polymerization is generally 30
To 130 ° C, preferably about 50 to 100 ° C, and the polymerization pressure is usually in the range of 0.1 to 5 MPaG. In the first-stage polymerization, MF is performed using a molecular weight modifier such as hydrogen.
Preferably, R is controlled to increase the fluidity of the final copolymer during melting.

Second Stage Polymerization The second stage polymerization is a process for producing a rubbery polymer by polymerizing a mixture of propylene and ethylene in a gas phase state in one or more polymerization tanks. In this second stage polymerization, the polymerization ratio (weight ratio) of propylene / ethylene is 90/10 to 10
It is desirable to produce a propylene rubbery polymer having a ratio of / 90, preferably 80/20 to 20/80, particularly preferably 70/30 to 30/70.

The polymerization amount in this step is 90 to 10% by weight of the total polymerization amount. In the second-stage polymerization, other comonomers may coexist in addition to propylene and ethylene.
For example, 1-butene, 1-pentene, 1-hexene, 4
Α-olefins such as -methyl-1-pentene can be used.

The polymerization temperature of the second stage polymerization is 30 to 110 ° C.
Preferably it is about 50 to 90 ° C. The polymerization pressure is usually in the range of 0.1 to 5 MPaG. When moving from the first-stage polymerization to the second-stage polymerization, it is preferable to purge with propylene gas or a propylene / ethylene mixed gas and hydrogen gas before moving to the next step. In the second-stage polymerization, a molecular weight regulator may or may not be used depending on the purpose.

Polymerization Mode The process for producing the copolymer according to the present invention is carried out by a continuous method. That is, a part of the polymer generated in the first-stage polymerization is continuously extracted, added to the second-stage polymerization, and then the second-stage polymerization is performed.

The first-stage polymerization may be performed by a bulk polymerization method in which polymerization is performed using propylene itself as a medium, or a gas phase polymerization method in which polymerization is performed in a gaseous monomer without using a medium. It is carried out in. The second stage polymerization is carried out by a gas phase polymerization method. A preferred polymerization mode of the gas phase polymerization method is, for example, a method of forming a fluidized bed by flowing the produced polymer particles with a monomer stream, or a method of stirring the produced polymer particles in a reaction vessel with a stirrer.

In the present invention, the electron-donating compound of the component (C) is added to both the polymer transfer section from the first-stage polymerization to the second-stage polymerization and the second-stage polymerization tank. It is characterized by being added.

The supply of the component (C) to the transfer section of the polymer is performed during the transfer of the polymer from the first-stage polymerization to the second-stage polymerization. As a method of adding the electron-donating compound to the polymer transfer section from the first-stage polymerization to the second-stage polymerization, a method of adding the electron-donating compound to a polymer transfer pipe from the first-stage polymerization tank to the second-stage polymerization tank, or There is a method in which a separate reaction tank is provided between the two-stage polymerization tank and the second-stage polymerization tank, and the reaction tank is added thereto. In this case, in addition to newly providing the reaction tank, it is also possible to use an existing tank in the middle of the transfer flow path, such as a degassing drum for purging monomers and hydrogen in the first-stage polymerization.

As a method of adding the electron donating compound to the second-stage polymerization tank, the electron-donating compound is added to the second-stage polymerization tank by providing a dedicated supply port, and is also accompanied by a reagent such as hydrogen. Or entrainment with the circulating monomer.

The addition amount of the component (C) is adjusted so that the activity of the second-stage polymerization becomes 0.3 to 0.95 times, preferably 0.5 to 0.9 times, when not added. If the activity of the second-stage polymerization is less than 0.3 times that in the case where no additive is added, a product having a sufficient copolymer content cannot be obtained. If the activity of the second-stage polymerization exceeds 0.95 times that of the case where no addition is made, the action of the electron donating compound becomes insufficient, and a sufficient gel reducing effect and adhesion preventing effect cannot be obtained.

In one aspect of the present invention, the amount of the component (C) added to the polymer transfer section from the first-stage polymerization to the second-stage polymerization is C ₁ , and the amount of the component (C) to the second-stage polymerization tank is Add C ₂
Then, C ₁ and C ₂ are controlled so as to satisfy the following equation (1).

0.05 ≦ C ₁ / (C ₁ + C ₂ ) ≦ 0.8 (1) When the value of the formula (1) is less than 0.05, the particles which the electron-donating compound cannot fully act on may be obtained. There is a possibility that a sufficient gel reduction effect and adhesion prevention effect cannot be obtained.

When the value of the equation (1) exceeds 0.8, the change in the activity with respect to the change in the added amount becomes large, and the operation control becomes difficult.

In one of the inventions of this patent,
While C ₁ and C ₂ satisfy the formula (1), a method of controlling the amount of addition to control the second-stage polymerization to have the above-mentioned activity can be adopted.

That is, when the component (C) is independently added to each of the polymer transfer section from the first-stage polymerization to the second-stage polymerization and the second-stage polymerization tank, the former amount C ₁ is used. a constant with respect to the amount of component (B), controls the activity of the second stage polymerization by adjusting the C _2. If C ₁ and C ₂ are independently changed to control the second-stage activity, the activity fluctuates greatly and operation is difficult. However, if the above method is used, the activity control changes the amount of C _2. It is possible to control relatively easily.

Further, the component (C ₁ ) from the supply device of the component C to the transfer section of the polymer from the first-stage polymerization to the second-stage polymerization
It is also possible to supply the component (C) by branching into a channel for adding the component (C) and a channel for adding the component (C ₂ ) to the second-stage polymerization tank.

In this case, the ratio of C ₁ to C ₂ is always kept constant even when the amount of component (C) is changed. The fluctuation of the two-step activity is also small.

In this case, the value of equation (1) is particularly preferably 0.5 or less from the viewpoint of controllability of operation.

[0082]

The following examples are provided to further illustrate the present invention. The present invention is not limited thereby without departing from the gist thereof.

Measurement of Physical Properties a. EPR content: EPR content is “CFC-
T-102L "was measured under the conditions shown in Table 1 by a temperature-elution fractionation method using a temperature-elution fractionation apparatus. In addition, EPR
Was an eluted component at 40 ° C. or lower.

Table 1 CFC measurement conditions Item Condition Sample concentration 2.0 mg / mL Solvent (flow rate) orthodichlorobenzene (1.0 mL / min) Column size 0.46 mmφ × 15 cm Filler Glass (0.1 mmφ) Temperature lowering rate 1 0.0 ° C./min Heating rate 1.0 ° C./min Injection amount 0.5 mL GPC column TSK GMHXL-HT (8 mmφ × 30 cm) × 3 GPC measurement temperature 135 ° C. Detector IR (MIRAN 1A) Measurement wavelength 3.42 μm Molecular weight conversion PP conversion b. Bulk density (ρB): The bulk density (ρB) is calculated according to JIS-
It was measured according to K-6721. c. Particle size distribution of the polymer: The particle size distribution of the polymer was measured using a standard sieve of Mitamura Riken Co., Ltd., and was measured by Rosin-Ram.
The slope of the mler plot was defined as the n term, and was used as a measure of the particle size distribution. Fractions below 75μ were expressed as fines in% by weight. d. MFR: Measured according to JIS-K-6758. e. Ti content in polypropylene polymer: The Ti content in the polypropylene polymer is 100% of the thickness of the polypropylene.
A μ sheet was prepared and quantified by X-ray fluorescence analysis.

In the following examples, Me is a methyl group, Et is an ethyl group, Bu is an n-butyl group,
h represents a phenyl group.

Example 1 (1) Production of solid catalyst component (A) In a 100 L autoclave equipped with a heating / cooling jacket, a stirrer, and a baffle, Mg (OEt) ₂ : 2
0 mol, and then Ti (OBu) ₄ was added to magnesium in the charged Mg (OEt) _2.
It was charged so that (OBu) ₄ /Mg=0.45 (molar ratio), and the temperature was increased while stirring at 165 rpm.

After reacting at 135 ° C. for 2.0 hours,
The temperature was lowered to 5 ° C., and a toluene solution of MeSi (OPh) ₃ was added to magnesium in Mg (OEt) ₂ , MeSi (OPh) ₃ /Mg=0.67 (molar ratio).
Was added so that After completion of the addition, the reaction was carried out at the same temperature for 4 hours. After the completion of the reaction, the temperature was lowered to 25 ° C. and Ti (OB
u) ₄ and Si (OEt) ₄ , and charged Mg (OEt) ₂
Ti (OBu) ₄ / Mg =
0.15 (molar ratio), Si (OEt) ₄ /Mg=0.0
5 (molar ratio) to obtain a slurry of the contact product (a ^* ).

Next, after diluting with toluene so that [Mg] = 0.53 mol / L · toluene, 165 r
While stirring at pm, the mixture was cooled to −10 ° C., and diethyl phthalate was added to magnesium in Mg (OEt) ₂ charged with diethyl phthalate / Mg = 0.10 (molar ratio).
Was added so that Subsequently, TiCl ₄ was added to magnesium in the charged Mg (OEt) ₂ ,
6.0 such that Cl ₄ /Mg=4.0 (molar ratio).
The solution was dropped over time to obtain a homogeneous solution. At this time, the phenomenon that the viscosity of the liquid increased and the liquid became gel-like did not occur.

The obtained homogeneous solution is heated at 20 ° C./Hr at 15 ° C.
And kept at the same temperature for 1 hour. Then again 2
After the temperature was raised to 50 ° C. at 0 ° C./Hr and maintained at 50 ° C. for 1 hour, the temperature was further raised to 117 ° C. at 120 ° C./Hr, and the treatment was performed at the same temperature for 1 hour.

After completion of the treatment, the heating and stirring were stopped, the supernatant was removed, and the residue was washed with toluene to a residual liquid ratio of 1/55 to obtain a solid slurry.

Next, the amount of toluene in the obtained solid slurry was adjusted so that the TiCl ₄ concentration was 1.5 mol / L · toluene, and TiCl ₄ was added at 25 ° C. in Mg (OEt) ₂ initially charged. Of magnesium, Ti
It was added so that Cl ₄ /Mg=5.0 (molar ratio). The temperature of the slurry was increased while stirring at 165 rpm, and the reaction was performed at 117 ° C. for 1 hour.

After completion of the reaction, the heating and stirring were stopped, the supernatant was removed, and the residue was washed with toluene to a residual liquid ratio of 1/150 to obtain a toluene slurry (A ^* ). .

A part of the solid slurry obtained here was transferred to a reaction tank having an inner diameter of 660 mm and a straight body portion of 770 mm and having a three-way sweeping blade, diluted with n-hexane, and adjusted to a concentration of 3 g (A ^* ). / L. While stirring this slurry at 300 rpm, triethylaluminum is converted into triethylaluminum / (A ^* ) = at 25 ° C.
3.44 mmol / g.
-Butylethyldimethoxysilane was added so that t-butylethyldimethoxysilane / (A ^* ) = 1.44 mmol / g. After completion of the addition, the mixture was kept at 25 ° C. for 30 minutes while continuously stirring.

Next, propylene gas was fed to the liquid phase at a constant speed over 72 minutes. After stopping the supply of the propylene gas, washing with n-hexane was performed by a sedimentation washing method to obtain a slurry of the solid catalyst component (A) at a residual liquid ratio of 1/12. The obtained solid catalyst component (A) is (A ^* )
Each gram of the component contained 2.9 g of a propylene polymer.

(2) Production of Propylene-Ethylene Block Copolymer As shown in the process shown in FIG. 2, a liquid phase polymerization tank 1 having an internal volume of 0.9 m ^{3 with} a stirrer and a 1.9 m ³ stirred gas phase Between the polymerization tanks 8, a classification system including a concentrator 3 (liquid cyclone) and a settling liquid classifier 4 and a degassing system including a double-pipe heat exchanger 5 and a fluidized flash tank 6 are incorporated. , A propylene-ethylene block copolymer was continuously produced.

Liquefied propylene was fed into the propylene polymerization tank 1 at 115 kg / Hr, and hydrogen was fed so that the hydrogen composition in the gas phase was 8.5 mol%. Also, triethylaluminum at 30.6 g / Hr, t
-Butyl-ethyldimethoxysilane was fed at 1.3 g / Hr. Further, the solid catalyst component obtained in Example 1 (1) was fed at 0.85 g / Hr as the (A ^* ) component.

The polymerization temperature was 70 ° C. and the pressure was 3.24M.
PaG and propylene partial pressure were adjusted to 2.76 MPaG, and the liquid volume in the polymerization tank was adjusted to 0.47 m ³ .

The slurry polymerized in the polymerization tank 1 had a slurry concentration of about 25% by weight, and was fed to the concentrator 3 using the slurry pump 2 at a volume flow rate of about 12 m ³ / Hr. From the upper part of the concentrator 3, a supernatant liquid containing almost no solid particles was taken out, and fed from the lower part of the hydrodynamic classifier 4 at a linear velocity of 4.1 cm / sec. On the other hand, the high-concentration slurry extracted from the lower part of the concentrator 3 was directly fed to the upper part of the hydraulic classifier 4 and brought into countercurrent contact with the supernatant.

Since the slurry extracted from the upper part of the liquid classifier 4 contains fine particles, it is circulated to the original propylene polymerization tank 1, and the slurry containing a large amount of large-particles is separated from the lower part of the classifier 4. Was extracted. The slurry concentration of the slurry was about 30% by weight. Further, the extraction rate of the slurry was adjusted to be 35 kg / Hr as the polypropylene particles contained in the slurry.

The average residence time of the polypropylene catalyst extracted from the lower part of the hydrodynamic classifier 4 in the propylene polymerization tank 1 and the circulation line is 1.8 hours, and the average particle diameter Dp
50 was 620 μm, and the average catalyst efficiency was 37,500 g / g. In addition, the value of this catalyst efficiency showed good agreement with the value of the catalyst efficiency obtained by measuring the Ti content of the polypropylene particles.

The slurry extracted from the lower part of the hydraulic classifier 4 was fed to the fluidized flash tank 6 via the downstream double-tube heat exchanger 5. In the fluidized flash tank 6, the temperature inside the tank was maintained at 70 ° C. while feeding heated propylene gas from below. The solid polypropylene particles obtained here were sent to a gas-phase polymerization tank 8, where propylene and ethylene were copolymerized.

Ethanol as a component (C ₁ ) was fed between the fluidized flash tank 6 and the gas phase polymerization tank 8 using the pump 7 at a rate of 6.2 g / Hr.

In order to enhance the mixing effect, a gaseous blower 10 circulated a mixed gas of ethylene, propylene, hydrogen and nitrogen in a gas phase polymerization tank 8 provided with an auxiliary stirring blade. Further, 8.6 g / Hr of ethanol was added as a component (C ₂ ) using the pump 9. The sum of the partial pressures of ethylene and propylene is 1.3.
7 MPaG, and the molar fraction of propylene is 55 mo
The feed was made constant at 1%. Also, hydrogen is
The feed was performed so that the hydrogen concentration became 1.8 mol%.
The polymerization temperature was adjusted to 70 ° C., and the average residence time in the gas phase polymerization tank 8 was adjusted to 2.3 hours.

The polymer particles extracted from the gas-phase polymerization tank 8 were analyzed at several points to find that MFR = 20 ± 1.5 g / 10
min, bulk density = 0.45-0.46 g / cc, EP
The R content is 25 ± 1% by weight, the activity in the gas phase polymerization tank 8 is 5440 g-PP / g · cat · hr, and the relative activity in the case where no electron donating compound is added is 0.70 g-PP / g · cat · hr.
Met.

Under these conditions, the polymerization operation was continued for 10 days, but no fouling was observed in the upper part of the gas phase polymerization tank or the gas circulation line.

Comparative Example 1 (1) Production of Propylene-Ethylene Block Copolymer In the process shown in FIG. 2, except that the amount of ethanol from pump 7 was changed to 11 g / Hr and the ethanol feed from pump 9 was stopped. In the same manner as in Example 1 (2), continuous production of a propylene-ethylene block copolymer was performed.

The polymer particles extracted from the gas-phase polymerization tank 8 were analyzed at several points. As a result, the EPR content varied between 22 and 30.5% by weight. , Indicating that stable control was not achieved.

Under these conditions, the polymerization operation was continued for 10 days, but no fouling was observed in the upper part of the gas phase polymerization tank or the gas circulation line. The activity in the gas phase polymerization tank 8 is 4600 to 7155 g-PP / g · cat · hr, and the relative activity with respect to the case where no electron donating compound is added is 0.
59-0.92.

Comparative Example 2 (1) Production of Propylene-Ethylene Block Copolymer In the process shown in FIG. 2, the ethanol feed from pump 7 was stopped, and the ethanol feed from pump 9 was changed to 17.3 g / Hr. Except for the above, continuous production of a propylene-ethylene block copolymer was carried out in the same manner as in Example 1 (2).

The polymer particles extracted from the gas-phase polymerization tank 8 were analyzed at several points to find that MFR = 20 ± 2 g / 10 mi
n, bulk density = 0.45 to 0.47 g / cc, EPR content = 25 ± 1% by weight, activity in the gas phase polymerization tank 8 was 5420 g-PP / g · cat · hr, and an electron donating compound was added. The relative activity for the case without was 0.69.

After continuous operation for 10 days under these conditions, each part was opened, but fouling was observed in the upper part of the gas phase reactor and the circulation line.

Example 2 (1) Production of Propylene-Ethylene Block Copolymer Continuous production of a propylene-ethylene block copolymer was carried out by the process shown in FIG.

In the first stage polymerization step, the same operation as in Example 1 (2) was performed. The polypropylene powder extracted from the lower part of the hydraulic classifier 4 was the same as in Example 1 (2).

Ethanol was added from pump 7 shown in FIG.
The feed was performed at 6.0 g / Hr (1.3 m.r.), of which 2 g / Hr was fed into a fluidized flash tank 6 and a gas phase polymerization tank 8.
And 14 g / Hr was adjusted to be fed to the gas circulation line of the gas phase polymerization tank 8.

In order to enhance the mixing effect, a gas mixture of ethylene, propylene, hydrogen and nitrogen was circulated by a gas blower 10 in a gas phase polymerization tank 8 provided with an auxiliary stirring blade. Ethylene and propylene were fed so that the sum of the partial pressures of ethylene and propylene was 1.37 MPaG and the mole fraction of propylene was constant at 55 mol%. Hydrogen was fed so that the hydrogen concentration was 1.8 mol%. The polymerization temperature was adjusted to 70 ° C., and the average residence time in the gas phase polymerization tank 8 was adjusted to 2.3 hours.

The polymer particles extracted from the gas phase polymerization tank 8 were analyzed at several points to find that MFR = 20 ± 2 g / 10 mi
n, bulk density = 0.45 to 0.46 g / cc, EPR content = 25 ± 1% by weight, activity in the gas phase polymerization tank 8 was 5400 g-PP / g · cat · hr, and an electron donating compound was added. The relative activity for the case without was 0.69.

Under the above conditions, the polymerization operation was continued for 10 days, but no fouling was observed in the upper part of the gas phase polymerization tank or the gas circulation line. Comparative Example 3 (1) Production of Propylene-Ethylene Block Copolymer In the process shown in FIG. 3, except that the ethanol feed from pump 7 was stopped and the average residence time in gas phase polymerization tank 8 was 1.6 hours. Carried out continuous production of a propylene-ethylene block copolymer in the same manner as in Example 1 (3).

The polymer particles extracted from the gas-phase polymerization tank 8 were analyzed at several points to find that MFR = 20 ± 2 g / 10 mi
n, bulk density = 0.31 to 0.33 g / cc, EPR content = 25 ± 1% by weight, and the activity in the gas phase polymerization tank 8 was 7810 g-PP / g · cat · hr.

After continuous operation for 10 days under these conditions, each part was opened, but fouling was observed in the upper part of the gas phase reactor and the circulation line. Table 2 summarizes the results of the above Examples and Comparative Examples.

[0120]

[Table 1]

[Brief description of the drawings]

FIG. 1 is a flowchart for assisting understanding of the present invention.

FIG. 2 is a flowchart showing a polymerization apparatus used in Example 1.

FIG. 3 is a flowchart showing a polymerization apparatus used in Example 2.

[Explanation of symbols]

 1, liquid phase polymerization tank 3, concentrator 4, sedimentation liquid classifier 5, double tube heat exchanger 6, fluidized flash tank 7, 9, pump 8, stirring type gas phase polymerization tank 10, gas blower 14 , Fine powder classification cyclone

Continued on the front page F-term (reference) 4J026 HA04 HA27 HA35 HA39 HA49 HB03 HB04 HB27 HB35 HB39 HB44 HB45 HB48 HE01 4J028 AA01A AB01A AC04A AC06A AC07A AC15A BA01A BA01B BB00A BB01B BC25ABC16BC25 BC25B16BCB25BC16BC CB36A CB42A CB42C CB44A CB44C CB56A CB63A CB63C CB66A CB66C CB81A CB81C EB04 EC01 ED01 ED02 ED09 FA01 FA04

Claims (4)

[Claims] 1. A propylene-ethylene block copolymer is produced by continuously performing the following first-stage polymerization and second-stage polymerization in the presence of a catalyst comprising the following components (A) and (B). In the method, the following component (C) is added to both the polymer transfer section from the first-stage polymerization to the second-stage polymerization and the second-stage polymerization tank to perform polymerization, and the amount of the component (C) added is The activity of the second-stage polymerization is from 0.3 to 0.3 when component (C) is not added.
A method for producing a propylene-ethylene block copolymer, which is adjusted to be 0.95 times. (A) a solid catalyst component containing titanium, magnesium, halogen and an electron donor as essential components (B) an organoaluminum compound (C) an electron donating compound (1) first-stage polymerization propylene alone or a mixture of propylene and ethylene, Producing a crystalline propylene polymer by polymerizing in one or more polymerization tanks in liquid propylene or in a gaseous phase; (2) second-stage polymerization A step of producing a rubbery copolymer by polymerization in one or more polymerization tanks. 2. The addition amount of the component (C) to the polymer transfer section from the first-stage polymerization to the second-stage polymerization is C ₁ , and the addition amount of the component (C) to the second-stage polymerization tank is C _2. that case, C ₁ and C ₂ are propylene according to claim 1, in which satisfy formula (1) - method of manufacturing ethylene block copolymer. 0.05 ≦ C ₁ / (C ₁ + C ₂ ) ≦ 0.8 (1) 3. The process for producing a propylene-ethylene block copolymer according to claim 2, wherein C ₁ is kept constant with respect to the amount of component B used, and C ₂ is varied to control the effect of adding component C. . 4. A supply path for the component C, a flow path for adding the component (C) from the supply device for the component C to a polymer transfer section from the first stage polymerization to the second stage polymerization, and a second stage polymerization tank. branches in the flow path for addition of component (C) to, in case of changing the added amount of the component (C), so that the ratio of C ₁ and C ₂ is always kept constant, claim 2 3. The method for producing a propylene-ethylene block copolymer according to item 1.