JPH0780943B2 - Method for producing high-rigidity polypropylene - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a high-rigidity polypropylene. More specifically, it relates to a method for producing a high-rigidity polypropylene having extremely excellent transparency.

[Prior Art and Its Problems] The present applicant uses a catalyst obtained by combining a titanium trichloride composition obtained by a specific method with an organoaluminum compound and an aromatic carboxylic acid ester in a specific use ratio. Method for producing high-rigidity polypropylene
58-104907, hereinafter referred to as the prior invention. According to the method of the prior invention, a molded article having significantly higher rigidity than polypropylene obtained by a conventionally known method can be obtained by the method of the prior invention, without adding any special additive. It has become possible to produce polypropylene.

However, although the polypropylene obtained by the method of the invention of the prior application has high rigidity as described above, it is semi-transparent, so the commercial value may be impaired in the field of use, and improvement in transparency is desired. It was rare.

The present inventors diligently studied a method for producing a high-rigidity polypropylene having improved transparency. As a result, a titanium trichloride composition similar to that used in the prior invention was combined with an organoaluminum compound, and a small amount of a specific aromatic monomer was polymerized with this to preactivate it. The polypropylene obtained by polymerizing propylene using a catalyst in which a specific amount of the ester is combined is not only extremely transparent as compared with the polypropylene obtained by the method of the prior invention, but also has rigidity. The inventors have found that the above can be further improved and have reached the present invention.

As is apparent from the above description, an object of the present invention is to provide a method for producing a high-rigidity polypropylene having remarkably excellent transparency. Another object is to provide a high rigidity polypropylene having remarkably excellent transparency.

[Means for Solving Problems] The present invention has the following configurations.

(1) A method for producing polypropylene by polymerizing propylene using a catalyst comprising a titanium trichloride composition (III), an organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E). As the titanium composition (III), a solid obtained by reacting an organoaluminum compound (A ₂ ) or a reaction product (I) of an organoaluminum compound (A ₂ ) and an ether (B ₁ ) with titanium tetrachloride. The product (II) is obtained by polymerizing it with an α-olefin, or without polymerizing it, and further reacting an ether (B ₂ ) with a halide of an element of Group III to VI of the periodic table. Titanium trichloride composition (II
I) is used, and the titanium trichloride composition (III) is combined with an organoaluminum compound (A ₁ ). (In the formula, n is either 0, 1, 2 or m is 1, 2 and R ¹ represents a hydrocarbon group having 1 to 12 carbon atoms which may contain silicon, hydrogen or halogen, When m is 2, each R ¹
May be the same or different. 0.001g per 1g of the titanium trichloride composition (III)
To 100 g of a pre-activated catalyst component obtained by a polymerization reaction, and if necessary, an additional organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E) are combined to obtain the aromatic carboxylic acid ester (E). And the molar ratio (E) / (I of the titanium trichloride composition (III) (the same applies to the Ti atom number standard)
II) = 0.1 to 10.0, and the molar ratio (A ₁ ) between the organoaluminum compound (A ₁ ) and the titanium trichloride composition (III).
/ (III) = 0.1 to 200, a method for producing a high-rigidity polypropylene, which comprises polymerizing propylene using a catalyst.

(2) The method according to the above item 1, wherein a dialkylaluminum monohalide is used as the organoaluminum compound (A ₁ ).

(3) The general formula of the organoaluminum compound (A ₂ ) is A 1
R ² _p R ³ _{p ′} X _{3- (p + p ′)} (wherein R ² and R ³ represent a hydrocarbon group such as an alkyl group, a cycloalkyl group, an aryl group or an alkoxy group, and X represents a halogen, and p, p'represents an arbitrary number of 0 <p + p'≤3).

(4) The isotactic pentad fraction (P) and (MFR) of polypropylene obtained by polymerization is in the range of 1.00 ≧ P ≧ 0.015 1og MFR + 0.955. The method described in.

The structure of the present invention will be described in detail below.

As the titanium trichloride composition (III) used in the present invention,
A titanium trichloride composition similar to that used in the prior invention is used. The details of the manufacturing method are detailed in the specification of the prior invention, but are as follows.

Solid product (II) obtained by reacting an organic aluminum compound (A ₂ ) or a reaction product (I) of an organic aluminum compound (A ₂ ) and an electron donor (B ₁ ) with titanium tetrachloride. Of the titanium trichloride composition (III) used in the present invention by subjecting the compound to a polymerization treatment with α-olefin, or further without reacting with a polymerization treatment, further reacting an electron donor (B ₂ ) with an electron acceptor.
Is obtained. Details of each step are as follows.

First, the reaction between the organoaluminum compound (A ₂ ) and the electron donor (B ₁ ) to obtain the reaction product (I) is carried out by using the solvent (D).
At -20 ° C to 200 ° C, preferably -10 to 100 ° C for 30 seconds to 5
Do on time. There is no limitation on the order of addition of (A ₂ ), (B ₁ ), and (D), and the amount ratio used is 1 mol of organoaluminum,
Ethers 0.1 to 8 mol, preferably 1 to 4 mol, solvent
0.5-5 l, preferably 0.5-2 l are suitable. Aliphatic hydrocarbons are preferred as the solvent. Thus, the reaction product (I) is obtained. The reaction product (I) can be subjected to the next reaction in a liquid state in which the reaction is completed (sometimes referred to as reaction product liquid (I)) without separation.

Next, the reaction between the reaction product (I) or the organoaluminum compound (A ₂ ) and titanium tetrachloride (C) is 0 to 200
C., preferably 10 to 90.degree. C. for 5 minutes to 8 hours. Although it is preferable not to use a solvent, an aliphatic or aromatic hydrocarbon can be used. The mixing of (A ₂ ) or (I), (C) and the solvent may be carried out in any order, and it is preferable that the mixing of the entire amount be completed within 5 hours. The amount of each used in the reaction is 1 to 1 mol of titanium tetrachloride, and the solvent is 0 to 3,000.
0 ml, the organoaluminum compound (A ₂ ) or the reaction product (I) is the ratio (Al / Ti) of the number of Al atoms in the (A ₂ ) or the (I) to the number of Ti atoms in the titanium tetrachloride. It is 0.05 to 10, preferably 0.06 to 0.3.

After completion of the reaction, the liquid portion is separated and removed by filtration or decantation, and the solid product (II) thus obtained is further washed with a solvent, and the obtained solid product (II) is suspended in the solvent to the next step. It may be used, or may be dried and taken out as a solid to be used.

Further, the solid product (II) obtained by reacting the organoaluminum compound (A ₂ ) or the reaction product (I) with titanium tetrachloride is polymerized with α-olefin and used in the next reaction. Is also possible.

In the present invention, "polymerizing" means that a small amount of α-olefin is brought into contact with the solid product (II) to polymerize the α-olefin. By this polymerization treatment, the solid product (II) is in a state of being coated with the polymer. As a method of polymerizing with an α-olefin, (1) a solid product obtained by adding α-olefin in any process of the reaction between the organoaluminum compound (A ₂ ) or the reaction product (I) and titanium tetrachloride A method of polymerizing (II), (2) after the reaction of the organoaluminum compound (A ₂ ) or the reaction product (I) with titanium tetrachloride, α-olefin is added to give a solid product (II). Polymerization method, (3) Solid obtained after completion of reaction of organoaluminum compound (A ₂ ) or reaction product (I) with titanium tetrachloride, separation and removal of liquid portion by filtration or decantation There is a method in which the product (II) is suspended in a solvent, an organoaluminum compound and α-olefin are further added, and a polymerization treatment is carried out.

When an α-olefin is added at any stage of the reaction between the organoaluminum compound (A ₂ ) or the reaction product (I) and titanium tetrachloride, and when the organoaluminum compound (A ₂ ) or the reaction product (I) and When the α-olefin is added after the reaction with titanium chloride, the reaction temperature
The α-olefin is added at atmospheric pressure or at a pressure of 10 kg / cm ² G or less at 30 to 90 ° C. for 5 minutes to 10 hours. The amount of α-olefin to be added is 0.05 g to 1,000 g using 10 to 5,000 g of α-olefin based on 100 g of the solid product (II).
g It is desirable to polymerize.

Polymerization treatment with α-olefin was obtained after the reaction between the organoaluminum compound (A ₂ ) or the reaction product (I) and titanium tetrachloride was completed, and then the liquid portion was separated and removed by filtration or decantation. When the solid product (II) is suspended in a solvent, the solid product (II) 10
0 g of solvent 100 ml to 2,000 ml, organoaluminum compound 0.5 g
Add ~ 5,000g, reaction temperature 30 ~ 90 ℃ for 5 minutes ~ 10 hours, α
-Add 10-5,000 g of olefin at 0-10 kg / cm ² G and add 0.0
It is desirable to polymerize 5 to 1,000 g.

The solvent is preferably an aliphatic hydrocarbon, and the organoaluminum compound may be the same as or different from that used for (A ₂ ). After completion of the reaction, the liquid portion is separated and removed by filtration or decantation, and after repeating washing with a solvent, the obtained solid product subjected to polymerization treatment (hereinafter referred to as solid product (II-A) (May be called) may be used in the next step in the state of being suspended in the solvent, or may be dried and taken out as a solid to be used.

The solid product (II) or the solid product (II-A) is then reacted with an ether (B ₂ ) and a halide (F) of an element of Group III to VI of the periodic table. This reaction can be carried out without using a solvent, but using an aliphatic hydrocarbon gives preferable results. The amount used is (B ₂ ) 0.1 g to 1,00 per 100 g of the solid product (II) or (II-A).
0 g, preferably 0.5 g to 200 g, (F) 0.1 g to 1,000 g, preferably 0.2 g to 500 g, solvent 0 to 3,000 ml, preferably 100 to
It is 1,000 ml. The reaction method is a solid product (II)
Or (II-A) with ethers (B ₂ ) and periodic table III
~ A method of simultaneously reacting a halide (F) of a group VI element, a method of reacting (F) with (II) or (II-A), and then a reaction with (B ₂ ), (II) or ( II-A)
After reacting (B ₂ ) with, then reacting with (F),
After reacting (B ₂ ) with (F), (II) or (II-A)
There is a method of reacting with, but any method may be used. The reaction conditions are 40 ° C. to 200 ° C. in the above method.
C., preferably 50 to 100 g. C. for 30 seconds to 5 hours, and in the method of (II) or (II
-A) and (B ₂ ) are reacted at 0 ° C to 50 ° C for 1 minute to 3 hours, and then (F) is reacted under the same conditions as described above. In another method, (B ₂ ) and (F) are
After reacting at 100 ° C. for 30 minutes to 2 hours, cooling to 40 ° C. or lower, adding (II) or (II-A), and then reacting under the same conditions as above. Solid product (II) or
After the reaction of (II-A), (B ₂ ) and (F) is completed, the liquid portion is separated and removed by filtration or decantation, and the washing with a solvent is repeated to obtain the titanium trichloride composition used in the present invention. (III) is obtained.

The titanium trichloride composition (III) obtained as described above is combined with an organoaluminum compound (A ₁ ), and this is combined with the following formula, (In the formula, n is either 0, 1, 2 or m is 1, 2 and R ¹ represents a hydrocarbon group having 1 to 12 carbon atoms which may contain silicon, hydrogen or halogen, When m is 2, each R ¹
May be the same or different. ) An aromatic monomer represented by the formula (hereinafter, may be abbreviated as a specific aromatic monomer) per 1 g of the titanium trichloride composition (III):
A catalyst for use in the present invention is obtained by combining a pre-activated catalyst component, which has been subjected to a polymerization reaction of 0.001 g to 100 g, and an additional organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E), if necessary. .

Pre-activation is based on 1 g of titanium trichloride composition (III),
Organoaluminum compound (A ₁ ) 0.005 g to 500 g, solvent 0
50 liters, hydrogen 0 to 1,000 ml, and specific aromatic monomers 0.
Use 01g to 1,000g.

The polymerization reaction temperature is 0 ° C to 100 ° C for 1 minute to 20 hours, and a specific aromatic monomer is reacted to give a titanium trichloride composition (III) 1
It is desirable to polymerize 0.001 g to 100 g, preferably 0.01 g to 100 g, of the specific aromatic monomer per g. The amount of polymerization reaction
If it is less than 0.001 g, the effect of improving transparency and rigidity is insufficient, and if it exceeds 100 g, the effect is not significantly improved, which is economically disadvantageous.

The preliminary activation can be carried out in a hydrocarbon solvent such as n-pentane, n-hexane, n-heptane or toluene, and hydrogen may be allowed to coexist during the preliminary activation. It is also possible to add the aromatic carboxylic acid ester (E) in advance in the preliminary activation.

After completion of the pre-activation reaction, the catalyst prepared by adding a required amount of the aromatic carboxylic acid ester (E) to the pre-activation catalyst component slurry can be used as it is for the polymerization of propylene, or a coexisting solvent can be used. The unreacted specific aromatic monomer and the organoaluminum compound (A ₁ ) are removed by filtration, and dried powder or a suspension is prepared by adding a solvent to the powder. A method in which an additional organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E) are used in combination as a catalyst for propylene polymerization, a coexisting solvent, and an unreacted specific aromatic monomer Is removed by evaporation under reduced pressure, or by a stream of an inert gas, etc., and the powder or granules or a suspension is prepared by adding a solvent to the powder or granules. (A ₁₎ was added and further a catalyst in combination with aromatic carboxylic acid ester (E), it is also possible to use in the polymerization of propylene.

During the polymerization of propylene, the titanium trichloride composition (III), the total amount of the organoaluminum compound (A ₁ ) including the additional organoaluminum compound (A ₁ ) and the aromatic carboxylic acid ester (E) Regarding the amount used, the aromatic carboxylic acid ester (E) and the titanium trichloride composition (III) have a molar ratio (E) / (III) of 1.0 to 10.0, and the organoaluminum compound (A ₁ ) and The titanium chloride composition (III) is used in a molar ratio (A ₁ ) / (III) of 1.0 to 200.

If the addition amount of the aromatic carboxylic acid ester (E) is small, the improvement of isotacticity will be insufficient, so that the rigidity will not be high, and if it is too large, the polymerization activity will decrease, which is not practical. The number of moles of the titanium trichloride composition (III) refers to the number of Ti gram atoms substantially contained in (III).

Three organoaluminum compound used in the production of titanium chloride composition (III) (A _2), the general formula ^{_{A1R 2 p R 3 p 'X}} 3- (p + p') ( in the formula used in the present invention, (formula Where R ² and R ³ represent a hydrocarbon group or an alkoxy group represented by an alkyl group, a cycloalkyl group or an aryl group, X represents a halogen, and p and p ′ are any number of 0 <p + p ′ ≦ 3. Represents an organic aluminum compound.

Specific examples thereof include trimethyl aluminum, triethyl aluminum, tri n-propyl aluminum, tri n-butyl aluminum, tri i-butyl aluminum, tri n-hexyl aluminum, tri i-hexyl aluminum, tri 2-methylpentyl aluminum,
Trialkylaluminums such as tri-n-octylaluminum and tri-n-decylaluminum, diethylaluminum monochloride, di-n-propylaluminum monochloride, di-butylaluminium monochloride, diethylaluminum monofluoride, diethylaluminum monobromide, Dialkyl aluminum monohalides such as diethyl aluminum monoiodide, dialkyl aluminum hydrides such as diethyl aluminum hydride, alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, ethyl aluminum dichloride, i-butyl aluminum dichloride, etc. Monoalkyl aluminum dihalides of Monoethoxy diethylaluminum, alkoxyalkyl aluminum such as diethoxy monoethyl aluminum can also be used to. Two or more kinds of these organoaluminum compounds may be mixed and used.

The (B ₁ ) and (B ₂ ) used in the present invention are ethers. In addition, the following other electron donors can be shared with the ethers. What is used as an electron donor is an organic compound having an atom of oxygen, nitrogen, sulfur, or phosphorus, that is, alcohols, esters, aldehydes, fatty acids, ketones, nitriles, amines, amides. , Urea or thioureas, isocyanates, azo compounds, phosphines, phosphites, phosphinites, hydrogen sulfide or thioethers, thioalcohols and the like. Specific examples of (B ₁ ) and (B ₂ ) include diethyl ether, di-n-propyl ether, di-n-butyl ether, diisocyanyl ether, and di-n-.
Ethers such as pentyl ether, di-n-hexyl ether, di-hexyl ether, di-n-octyl ether, di-octyl ether, di-n-dodecyl ether, diphenyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, etc. Examples of the electron donor include alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, phenol, cresol, xylenol, ethylphenol, and naphthol, or phenols, methyl methacrylate, ethyl acetate, butyl formate. , Amyl acetate, vinyl butyrate, vinyl acetate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, 2-ethylhexyl benzoate, methyl toluate, ethyl toluate , 2-ethylhexyl toluate, methyl anisate, ethyl aniate, propyl anisate, ethyl cinnamate, methyl naphthoate, ethyl naphthoate, propyl naphthoate, butyl naphthoate, 2-ethylhexyl naphthoate, ethyl phenylacetate, etc. , Aldehydes such as acetaldehyde and benzaldehyde, fatty acids such as formic acid, acetic acid, propionic acid, butyric acid, oxalic acid, succinic acid, acrylic acid and maleic acid,
Aromatic acids such as benzoic acid, methyl ethyl ketone, methyl isobutyl ketone, ketones such as benzophenone, nitriles such as acetonitrile, methylamine, diethylamine, tributylamine, triethanolamine, β
(N, N-dimethylamino) ethanol, pyridine, quinoline, α-picoline, 2,4,6-trimethylpyridine, N,
Amines such as N, N ′, N′-tetramethylethylenediamine, aniline and dimethylaniline, formamide,
Hexamethylphosphoric triamide, N, N, N ', N', N "-pentamethyl-N'-β-dimethylaminomethylphosphoric triamide, octamethylpyrophosphoramide and other amides, N, N, N ' , N′-tetramethylurea and other ureas,
Isocyanates such as phenyl isocyanate and toluyl isocyanate, azo compounds such as azobenzene,
Phosphines such as ethylphosphine, triethylphosphine, tri-n-butylphosphine, tri-n-octylphosphine, triphenylphosphine, triphenylphosphine oxide, dimethylphosphite, di-n-octylphosphite, triethylphosphite, tri-n-
Butyl phosphite, triphenyl phosphite and other phosphites, ethyl diethyl phosphinite, ethyl butyl phosphinite, phenyl diphenyl phosphinite and other phosphinites, diethyl thioether, diphenyl thioether, methylphenyl thioether, ethylene sulfide, propylene Examples thereof also include thioethers such as sulfide, ethylthioalcohol, n-propylthioalcohol, and thioalcohols such as thiophenol. These electron donors can also be used as a mixture. Reaction product (I)
Each of the ethers (B ₁ ) for obtaining the compound (B ₁ ) and the solid product (II) or (B ₂ ) reacted with (II-A) may be the same or different.

The (F) used in the present invention is a halide of an element of Group III to VI of the periodic table. Specific examples include anhydrous aluminum chloride, silicon tetrachloride, stannous chloride, stannic chloride, titanium tetrachloride, zirconium tetrachloride, phosphorus trichloride, phosphorus pentachloride, vanadium tetrachloride, antimony pentachloride and the like. These can also be used as a mixture. Most preferred is titanium tetrachloride.

The following solvents are used. Examples of the aliphatic hydrocarbon include n-pentane, n-hexane, n-heptane, n-octane, i-octane and the like, and carbon tetrachloride, chloroform instead of or together with the aliphatic hydrocarbon. It is also possible to use halogenated hydrocarbons such as dichloroethane, trichloroethylene, and tetrachloroethylene. As aromatic compounds, aromatic hydrocarbons such as naphthalene, and mesitylene which is a derivative thereof,
Durene, ethylbenzene, isopropylbenzene, 2
Alkyl-substituted compounds such as -ethylnaphthalene and 1-phenylnaphthalene, and halides such as monochlorobenzene, chlorotoluene, chlorxylene, chloroethylbenzene, dichlorobenzene and bromobenzene are shown.

As the α-olefin used for the polymerization treatment, linear monoolefins such as ethylene, propylene, butene-1, pentene-1, and hexene-1, 4-methyl-pentene-1, 2-methyl-pentene-1 and the like. Branched chain mono-olefins and the like are used. These α-olefins may be used as a mixture of two or more α-olefins.

The specific aromatic monomer used for pre-activation is represented by the following formula, (In the formula, n is 0, 1, 2 or m is 1, 2 and R ¹ represents a hydrocarbon group having 1 to 12 carbon atoms which may contain silicon, hydrogen or halogen, m is 2
Then each R ¹ may be the same or different. ) Is an aromatic monomer. Specific examples thereof include styrene and its derivatives o-methylstyrene, p-
Alkyl styrenes such as t-butyl styrene, dialkyl styrenes such as 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene and 3,5-dimethylstyrene, 2-methyl-4-fluoro Styrene, halogen-substituted alkylstyrenes such as 2-ethyl-4-chlorostyrene, o-fluorostyrene, halogen-substituted styrenes such as p-fluorostyrene, p-trimethylsilylstyrene, m-trimethylsilylstyrene, p-triethylsilylstyrene, m-triethylsilylstyrene,
Trialkylsilylstyrenes such as p-ethyldimethylsilylstyrene, o-allyltoluene, allyltoluenes such as p-allyltoluene, 2-allyl-p-xylene, 4-allyl-o-xylene, 5-allyl-m. -Allylxylenes such as xylene, and 4- (o-tolyl)
Examples thereof include -1-butene and 1-vinylnaphthalene, and one or more kinds of these specific aromatic monomers are used.

Dialkylaluminum monohalide is preferably represented by titanium trichloride composition (III) and combined with the organoaluminum compound (A _1), and the general formula AlR ⁴ as the organic aluminum compound (A ₁₎ used if necessary R ⁵ X . In the formula, R ⁴ and R ⁵ represent a hydrocarbon group such as an alkyl group, an aryl group, an alkaryl group, a cycloalkyl group or an alkoxy group, X represents halogen, and specific examples thereof include diethylaluminum monochloride. , N-
Examples include propyl aluminum monochloride, di i-butyl aluminum monochloride, di n-butyl aluminum monochloride, diethyl aluminum monoiodide, diethyl aluminum monobromide and the like.

Specific examples which can be used as the aromatic carboxylic acid ester (E) which is another component constituting the catalyst include ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, 2-ethylhexyl benzoate,
Methyl toluate, ethyl toluate, toluic acid 2-
Ethylhexyl, methyl anisate, ethyl anisate, propyl anisate, ethyl cinnamate, methyl naphthoate,
Propyl naphthoate, butyl naphthoate, naphthoic acid 2
-Ethylhexyl, ethyl phenylacetate and the like.

The catalyst thus obtained for use in the present invention is used for the polymerization of propylene. As a polymerization mode for polymerizing propylene, propylene is n-hexane, n-heptane,
It can be carried out by slurry polymerization carried out in a hydrocarbon solvent such as n-octane, benzene or toluene, or by bulk polymerization and gas phase polymerization carried out in liquefied propylene.

Regarding the crystallinity of the polymer capable of exerting the effects of the present invention with respect to the polypropylene obtained by the various polymerization modes described above, the isotactic pentad fraction (P) is MF.
In relation to R, the range is 1 ≧ P ≧ 0.015 log MFR + 0.955. The higher the MFR is, the higher the P tends to be, and the MFR is usually 0.05 to 200, preferably about 0.1 to 100 is practical.

The polymerization temperature is usually 20 to 100 ° C, preferably 40 to 85 ° C. If the temperature is too low, the polymerization activity becomes low, which is not practical, and if the temperature is high, it becomes difficult to increase the isotacticity. Polymerization pressure is normal pressure to 50 kg / cm ²
It is usually carried out in G for about 30 minutes to 15 hours. At the time of polymerization, the addition of an appropriate amount of hydrogen for controlling the molecular weight is the same as the conventional polymerization method.

Thus, the polypropylene obtained by the method of the present invention is a high-rigidity polypropylene having remarkably high transparency, and is used for various molded articles by the known techniques such as injection molding, vacuum molding, extrusion molding and blow molding. It

[Operation] Since the high-rigidity polypropylene obtained by the method of the present invention contains a specific aromatic polymer having high stereoregularity in a dispersed state, the specific aromatic polymer can be formed during melt molding. By exhibiting a nucleating action, the crystallization of polypropylene is promoted, and as a result, the transparency and crystallinity of the entire polypropylene are increased.

Further, since the specific aromatic polymer introduced by the method of the present invention is a stereoregular high molecular weight polymer as described above, it does not bleed on the surface.

[Examples] Hereinafter, the present invention will be described with reference to Examples. The definitions of terms used in Examples and Comparative Examples and the measuring methods are as follows.

(1) CY: Titanium trichloride composition (III) showing polymerization activity
It represents the polymer yield (g) per gram. (Unit: g / g) (2) MFR: (Melt flow rate JIS K 7210 According to condition 14 in Table 1. (Unit: g / 10 min) (3) Isotactic pentad fraction (P): It is measured based on. Isotactic fraction in pentad units in the polypropylene molecular chain using ¹⁰ C-NMR.

(4) Internal haze: The haze inside the film excluding the effect of the surface, using a press machine at a temperature of 200 ° C and a pressure of 200 kg.
A polypropylene film with a thickness of 150μ was prepared under the condition of / cm ² G, and liquid paraffin was applied to both sides of the film.
The haze was measured according to SK 7105.

(Unit:%) (5) Crystallization temperature: Measured with a differential scanning calorimeter at a descending rate of 10 ° C / min. (Unit: ° C) (6) Rigidity: Tetrakis [methylene-3- (3 ', 5'-di-t-butyl-
4'-hydroxyphenyl) propionate] methane 0.
1 part by weight and 0.1 part by weight of calcium stearate were mixed, and the mixture was granulated using an extruder having a screw diameter of 40 mm. Then, the granulated product is made into a JIS type test piece at a molten resin temperature of 230 ° C. and a mold temperature of 50 ° C. with an injection molding machine, and the test piece is left for 72 hours in a room at a humidity of 50% and a room temperature of 23 ° C. Was measured by the following method.

(A) Flexural modulus: JIS K 7203 compliant (unit: kgf / cm ² ) (b) Tensile strength: JIS K 7113 compliant (unit: kgf / cm ² ) (c) Rockwell hardness (R scale): Compliant with JIS K 7202 (D) Heat distortion temperature (HDT): Compliant with JIS K 7207 (Unit:
C.) Example 1 (1) Preparation of titanium trichloride composition (III) 25 parts of n-hexane 6 l, diethylaluminum monochloride (DEAC) 5.0 mol, diisoamyl ether 12.0 mol 25
The mixture was mixed at 1 ° C for 1 minute and reacted at the same temperature for 5 minutes to produce a reaction product liquid (I) (diisoamyl ether / DEAC molar ratio (2.
4) got. 40 mol of titanium tetrachloride was placed in a reactor purged with nitrogen and heated to 35 ° C., and the reaction product solution (I) was added thereto.
After dropping all of the above in 30 minutes, keep the same temperature for 30 minutes,
The temperature was raised to ℃ and the reaction was continued for another 1 hour, the mixture was cooled to room temperature, the supernatant was removed, 20 l of n-hexane was added, and the supernatant was removed by decantation was repeated 4 times to obtain a solid product (II).
Got

The whole amount of this (II) was suspended in 30 liters of n-hexane, 200 g of diethylaluminum monochloride was added, 1.0 kg of propylene was added at 30 ° C., and the mixture was reacted for 1 hour to give a solid product (II-A ) Got. (Propylene reaction amount 60
0g). After the reaction, the supernatant was removed and n-hexane 300 ml
Repeat the operation of adding and removing by decantation twice,
2.5 kg of the solid product (II-A) subjected to the above-mentioned polymerization treatment
-Suspended in 6 liters of hexane, added 3.5 kg of titanium tetrachloride at room temperature for about 10 minutes, and reacted at 80 ° C for 30 minutes,
Further, 1.6 kg of diisoamyl ether was added and the reaction was carried out at 80 ° C for 1 hour. After the reaction was completed, the supernatant was removed by decantation, 40 l of n-hexane was added, and the mixture was stirred for 10 minutes,
The operation of leaving still and removing the supernatant was repeated 5 times, and then dried under reduced pressure to obtain a titanium trichloride composition (III). The titanium content in 1 g of the titanium trichloride composition (III) was 192 mg.

(2) Preparation of pre-activated catalyst component After replacing a stainless steel reactor with an inclined blade with an internal volume of 80 l with nitrogen gas, 40 l of n-hexane, 220 g of diethylaluminum monochromate, and the titanium trichloride composition obtained in (1) After adding 450 g of compound (III) at room temperature, the temperature in the reactor is adjusted to 40
C., 4.5 kg of 2.4-dimethylstyrene was added, and the mixture was reacted at 40.degree. C. for 2 hours (per 1 g of titanium trichloride composition (III), 2,4
-1.0 g reaction of dimethylstyrene).

After completion of the reaction, unreacted 2,4-dimethylstyrene, solvent and the like were filtered off, washed with n-hexane and dried to obtain a preactivated catalyst component in the form of powder.

(3) Polymerization of propylene After replacing a stainless steel reactor having an internal volume of 500 liters with a stirrer with nitrogen gas, 200 liters of n-hexane, 70 g of diethylaluminium monochloride, (2) were added to the pre-activated catalyst component at room temperature. 20 g of titanium trichloride composition (III), p
12 g of methyl toluate and 200 Nl of hydrogen were added. Subsequently, propylene was polymerized at a polymerization temperature of 70 ° C. and a propylene partial pressure of 10 kg / cm ² G for 3 hours. After completion of the reaction, 10 l of methanol was supplied and treated at 70 ° C for 30 minutes, and then unreacted propylene and unreacted hydrogen were discharged. 20% by weight
100 g of aqueous sodium hydroxide solution was added and treated at 70 ° C. for 20 minutes. Subsequently, 100 l of pure water was added, and after stirring for 10 minutes, the operation of extracting the aqueous layer was performed twice, and then the polymer slurry was extracted, filtered and dried to obtain a polymer. Since the obtained polymer contained lumps, it was pulverized with a pulverizer to obtain 59.2 kg of MFR1.5 polypropylene.

Comparative Example 1 The titanium trichloride composition (II) obtained in (1) of Example 1 in place of the pre-activated catalyst component in (3) of Example 1 (II
I) in an amount of 10 g and the amounts of diethylaluminum monochloride and methyl p-toluate used respectively.
Polypropylene was obtained in the same manner except that the ratio was 1/2.

Examples 2 and 3 Polypropylene was obtained in the same manner as in Comparative Example 1 except that the hydrogen charging amount was changed to 300 l (Example 2) and 600 l (Example 3) in (3) of Example 1.

Comparative Examples 2 and 3 Polypropylene was obtained in the same manner as in Example 1 except that the hydrogen charging amount was changed to 270 l (Comparative Example 2) and 540 l (Comparative Example 3) in (3) of Example 1.

Comparative Example 4 A preactivated catalyst component was obtained in the same manner as in (2) of Example 1 except that 560 g of propylene was used instead of 2,4-dimethylstyrene. )
Polymerization of propylene was carried out in the same manner as above to obtain polypropylene.

Comparative Example 5 A polypropylene was obtained in the same manner as in Comparative Example 1 except that the catalyst component methyl p-toluate in Comparative Example 1 (3) was not used.

Comparative Example 6 and Examples 4 and 5 In (2) of Example 1, 4-allyl-o-xylene was used in place of 2,4-dimethylstyrene, and the amounts thereof were changed to 1 g, 400 g and 12 kg, respectively. A polypropylene was obtained in the same manner as in Example 1 except that the pre-activation reaction was performed.

Comparative Examples 7 to 9 and Examples 6 and 7 In (2) of Example 1, 1.5 kg of p-trimethylsilylstyrene was used in place of 2,4-dimethylstyrene, and in (3), methyl p-toluate was used. A polypropylene was obtained in the same manner as in Example 1 except that the molar ratio of the titanium trichloride composition (III) to the titanium trichloride composition (III) was changed as shown in the table below. However, in Comparative Examples 7 and 8 and Example 6, the titanium oxide trichloride composition (III) was used as the pre-activated catalyst component during the propylene polymerization of (3).
g, and 35 g of diethyl aluminum monochloride were used.

Example 8 (1) Preparation of titanium trichloride composition (III) 8 l of n-heptane, 16 mol of di-n-butylaluminum monochloride and 10 mol of di-n-butyl ether were mixed at 30 ° C for 10 minutes and reacted for 20 minutes. Then, a reaction product liquid (I) was obtained. The whole amount of this reaction product liquid (I) was added dropwise to a solution consisting of 5 liters of toluene and 64 mol of titanium tetrachloride kept at 45 ° C for 60 minutes, then heated to 85 ° C and further reacted for 2 hours. ,
The mixture was cooled to room temperature, the supernatant was removed, 30 l of n-heptane was added, and the operation of removing the supernatant by decantation was repeated twice to obtain 4.9 kg of a solid product (II). The whole amount of this (II) was suspended in 30 l of n-heptane, 2.0 kg of di-n-butyl ether and 15 kg of titanium tetrachloride were added at room temperature for about 20 minutes, and the mixture was reacted at 90 ° C for 2 hours, cooled, and then decanted. It was washed with n-heptane and dried to obtain a titanium trichloride composition (III). The content of titanium atoms in 1 g of the titanium trichloride composition (III) was 255 mg.

(2) Preparation of pre-activated catalyst component In (2) of Example 1, the titanium trichloride composition (II
Titanium trichloride composition (III) obtained in (1) above as I)
Using 450 g and instead of 2,4-dimethylstyrene,
A preactivated catalyst component was obtained in the same manner as in (2) of Example 1 except that 6.5 kg of 2-methyl-4-fluorostyrene was used.

(3) Polymerization of Propylene In (3) of Example 1, 36 g (20 g of titanium trichloride composition (III)) of the pre-activated catalyst component obtained in (2) above was used as the pre-activated catalyst component, Example 1 except that the amount of methyl p-toluate added was 16 g.
Polypropylene was obtained in the same manner as in (3).

Comparative Example 10 In place of the pre-activated catalyst component in (3) of Example 8, the titanium trichloride composition (II
I) Polypropylene was obtained in the same manner except that 20 g was used.

Example 9 (1) Preparation of titanium trichloride composition (III) 27.0 mol of titanium tetrachloride was added to 12 liters of n-hexane and the temperature was 1 ° C.
After cooling to 1, 22.5 l of n-hexane containing 27.0 mol of diethylaluminum monochloride was further added dropwise at 1 ° C over 4 hours. After the completion of the dropping, the reaction was carried out at the same temperature for 15 minutes, the temperature was raised to 65 ° C. over 1 hour, and the reaction was further performed at the same temperature for 1 hour. Next, the supernatant was removed, and n-hexane 10
The procedure of adding l and removing by decantation was repeated 5 times. Of 5.7 kg of the obtained solid product (II), 1.8 kg
-Suspended in hexane 11 to which 1.8 l diisoamyl ether was added. After stirring this suspension at 35 ° C for 1 hour,
It was washed 5 times with 3 l of n-hexane to obtain a treated solid. The treated solid obtained was treated with 6 l of n-hexane solution containing 40% by volume of titanium tetrachloride.
Suspended in.

This suspension was heated to 65 ° C. and reacted at the same temperature for 2 hours. After the reaction was completed, 20 l of n-hexane was used once and 3
The solid thus obtained was washed and then dried under reduced pressure to obtain a titanium trichloride composition (III).

(2) Preparation of pre-activated catalyst component In (2) of Example 1, the titanium trichloride composition (II
Titanium trichloride composition (III) obtained in (1) above as I)
A pre-activated catalyst component was obtained in the same manner as in (2) of Example 1 except that 450 g was used and 1.5 kg of styrene was used instead of 2,4-dimethylstyrene.

(3) Polymerization of Propylene In (3) of Example 1, 60 g (20 g of titanium trichloride composition (III)) of the pre-activated catalyst component obtained in (2) above was used as the pre-activated catalyst component, , Polypropylene was obtained in the same manner as in (3) of Example 1 except that the amount of methyl p-toluate added was 17 g.

Comparative Example 11 The titanium trichloride composition (II) obtained in (1) of Example 9 in place of the pre-activated catalyst component in (3) of Example 9 (II
Polypropylene was obtained in the same manner except that 20 g of I) was used.

Example 10 (1) Preparation of titanium trichloride composition (III) n-heptane 4l, diethylaluminum monochloride
After 5.0 mol, 9.0 mol of diisoamyl ether, and 5.0 mol of di-n-butyl ether were reacted at 18 ° C for 30 minutes, the reaction solution was added dropwise to 27.5 mol of titanium tetrachloride at 40 ° C over 300 minutes, and then at the same temperature. After reacting for 1.5 hours, the temperature was raised to 85 ° C and the reaction was continued for 1 hour. The supernatant was removed and n-hexane was added.
The operation of adding 20 liters and removing by decantation was repeated 6 times, and 1.8 kg of the obtained solid product (II) was added to 50 liters of n-hexane.
Suspended in the solution, added 200 g of diethylaluminum monochloride, added 1.0 kg of propylene at 60 ° C., and reacted for 1 hour,
A solid product (II-A) subjected to a polymerization treatment was obtained (propylene reaction amount 0.5 kg). After the reaction, the supernatant liquid was removed, 30 l of n-hexane was added, and the operation of removing by decantation was repeated twice, and the solid product (II-A) was subjected to the above-mentioned polymerization treatment.
(2.3 kg) was suspended in 4 l of n-hexane, 1.8 kg of titanium tetrachloride and 1.8 kg of n-butyl ether were added, and the mixture was reacted at 60 ° C for 3 hours. After the reaction was completed, the supernatant was decanted off, 20 l of n-hexane was added, and the mixture was stirred for 5 minutes and allowed to stand to remove the supernatant, which was repeated 3 times, then dried under reduced pressure to form a titanium trichloride composition. The thing (III) was obtained. The titanium atom content in 1 g of the titanium trichloride composition (III) was 200 mg.

(2) Preparation of pre-activated catalyst component Titanium trichloride composition (III) in (2) of Example 1
As the titanium trichloride composition (III) 450 obtained in (1) above
g, and instead of 2,4-dimethylstyrene, P
Example 1 except that 1.3 g of -t-butylstyrene is used
A preactivated catalyst component was obtained in the same manner as in (2).

(3) Polymerization of Propylene In (3) of Example 1, 50 g (20 g as titanium trichloride composition (III)) of the pre-activated catalyst component obtained in the above (2) as the pre-activated catalyst component, aromatic Polypropylene was obtained in the same manner except that 15 g of ethyl p-anisate was used as the carboxylic acid ester, and 53 g of diethylaluminum monoiodide and 37 g of di-n-propylaluminum monochloride were used as the organic aluminum compound.

Comparative Example 12 The titanium trichloride composition (II) obtained in (1) of Example 10 in place of the pre-activated catalyst component in (3) of Example 10 (II
A polypropylene was obtained in the same manner except that 20 g of I) was used.

The following table shows the main polymerization conditions and the polymerization results of the above Examples and Comparative Examples and the evaluation results of the obtained polypropylene.

[Effect of the Invention] The main effect of the present invention is to obtain a polypropylene having extremely high transparency and rigidity.

As is apparent from the above-mentioned examples, the internal haze of the film produced by using the polypropylene obtained by the method of the present invention is 2 / when compared with the case where the pre-activation by the specific aromatic monomer is not performed. It is 5 to 3/5 and has extremely high transparency. Further, the crystallization temperature is increased by 2 ° C to 4 ° C as compared with the polypropylene obtained by the method of the invention of the prior application, and the crystallinity is remarkably improved, so that the flexural modulus is further improved.

[Brief description of drawings]

FIG. 1 is a manufacturing process diagram (flow chart) for explaining the method of the present invention.

Claims (4)

[Claims] 1. A method for producing polypropylene by polymerizing propylene using a catalyst comprising a titanium trichloride composition (III), an organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E), The titanium trichloride composition (III) is obtained by reacting an organoaluminum compound (A ₂ ) or a reaction product (I) of an organoaluminum compound (A ₂ ) and an ether (B ₁ ) with titanium tetrachloride. Obtained by polymerizing the solid product (II) with an α-olefin, or without polymerizing it, and further reacting an ether (B ₂ ) with a halide of an element of Group III to VI of the periodic table. Titanium trichloride composition (III)
By combining the titanium trichloride composition (III) and the organoaluminum compound (A ₁ ) with the following formula: (In the formula, n is either 0, 1, 2 or m is 1, 2 and R ¹ represents a hydrocarbon group having 1 to 12 carbon atoms which may contain silicon, hydrogen or halogen, When m is 2, each R ¹
May be the same or different. 0.001g per 1g of the titanium trichloride composition (III)
To 100 g of a pre-activated catalyst component obtained by a polymerization reaction, and if necessary, an additional organoaluminum compound (A ₁ ) and an aromatic carboxylic acid ester (E) are combined to obtain the aromatic carboxylic acid ester (E). And the molar ratio (E) / (I of the titanium trichloride composition (III) (the same applies to the Ti atom number standard)
II) = 0.1 to 10.0, and the molar ratio (A ₁ ) between the organoaluminum compound (A ₁ ) and the titanium trichloride composition (III).
/ (III) = 0.1 to 200, a method for producing a high-rigidity polypropylene, which comprises polymerizing propylene using a catalyst. 2. The method according to claim 1, wherein a dialkylaluminum monohalide is used as the organoaluminum compound (A ₁ ). 3. An organoaluminum compound (A ₂ ) having a general formula of A ₁ R ² _p R ³ _{p ′} X _{3- (p + p ′)} (wherein R ² and R ³ are alkyl groups, cycloalkyl groups, aryl groups, etc.). A hydrocarbon group or an alkoxy group, wherein X represents halogen, and p and p'represent any number of 0 <p + p'≤3). The method described in. 4. A polypropylene obtained by polymerization, wherein the relationship between the isotactic pentad fraction (P) and (MFR) is within the range of 1.00 ≧ P ≧ 0.015 1og MFR + 0.955. The method according to item 1.