JP2001146504A - Propylene polymer and film using the same - Google Patents

Abstract

[PROBLEMS] To provide a polypropylene film having excellent antistatic performance and high rigidity. A film using a composition obtained by blending an antistatic agent with a propylene polymer having the following characteristics: A propylene homopolymer or a copolymer of propylene with one or more olefins selected from ethylene and α-olefins having 4 or more carbon atoms, wherein the propylene content in the copolymer is 98% by weight or more; Flow rate is 0.5 to 20 (dg / min) Isotactic pentad fraction [mmmm] is 0.89 to 0.95
Boiling pentane extraction rate (C5-Ext) is 0.5% by weight or more, and boiling heptane extraction rate (C7-Ext) is 5% by weight.
Hereinafter, (C7-Ext)> 3.5 · (C5-Ex
t) The weight-average molecular weight of the soluble component at 0 ° C. or less by cross separation method is 7 × 10 ⁴ or more, and the weight-average molecular weight of the soluble component at 50 ° C. or less is 6 × 10 ⁴ or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a propylene-based polymer and a film comprising the same. More specifically, the present invention relates to a polypropylene film having excellent antistatic performance and high rigidity, and a propylene-based polymer capable of providing the same.

[0002]

2. Description of the Related Art Polypropylene films are widely used as packaging materials because of their excellent rigidity, transparency and gloss. However, since the polypropylene film has a high electric insulation resistance and is easily charged with static electricity, various problems occur in practical use. When imparting antistatic performance to a polypropylene film by adding an antistatic agent, it is necessary to add a large amount of an antistatic agent in order to obtain sufficient performance. There were problems such as bleed-out on the film surface. Further, there is an attempt to improve the antistatic performance of the added antistatic agent by lowering the crystallinity of polypropylene, but there is a problem that although the antistatic performance is improved, the rigidity of the obtained polypropylene film is reduced. I was

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polypropylene film having excellent antistatic performance and high rigidity, and a propylene-based polymer capable of producing the same. In detail, practically sufficient antistatic performance can be obtained by adding a small amount of antistatic agent compared to conventional polypropylene, and more excellent antistatic performance than conventional with the same amount of antistatic agent added And polypropylene having high rigidity and a propylene-based polymer capable of providing the same.

[0004]

Means for Solving the Problems The present inventors have intensively studied to solve the above problems. As a result, melt flow rate, isotactic pentad fraction, boiling pentane extraction rate, boiling heptane extraction rate, and 0
The weight-average molecular weight of the soluble component below 50 ° C and the weight-average molecular weight of the soluble component below 50 ° C by the cross fractionation method are in a specific range, and the boiling pentane extraction ratio and the boiling heptane extraction ratio are in a specific relationship. Using a propylene-based polymer, and blending an antistatic agent with the propylene polymer, found that a polypropylene film having excellent antistatic performance and high rigidity was obtained, and based on this finding, completed the present invention. .

[0005] The present invention comprises the following. (1) A propylene-based polymer having the following characteristics: A propylene homopolymer or a copolymer of propylene and one or more olefins selected from ethylene and α-olefins having 4 or more carbon atoms, wherein the propylene content in the copolymer is 98% by weight or more. Certain propylene-olefin copolymers. Melt flow rate (MFR: 230 ° C, 21.18)
N) is in the range of 0.5 to 20 (dg / min). Isotactic pentad fraction [mmmm] is 0.
It is in the range of 89 to 0.95. Boiling pentane extraction rate (C5-Ext) is 0.5% by weight
As described above, the boiling heptane extraction rate (C7-Ext) is 5% by weight or less, and (C7-Ext)> 3.5 · (C5
-Ext). The weight-average molecular weight of the soluble component at 0 ° C. or less by cross fractionation is 7 × 10 ⁴ or more, and the weight-average molecular weight of the soluble component at 50 ° C. or less is 6 × 10 ⁴ or more.

(2) A film formed by forming a polypropylene composition obtained by adding an antistatic agent to the propylene-based polymer according to the above (1).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. (1) Propylene Polymer of the Present Invention The propylene polymer of the present invention is a copolymer of propylene and one or more olefins selected from ethylene and α-olefins having 4 or more carbon atoms and propylene. It is united. When the propylene-based polymer is a copolymer, the propylene content in the copolymer is 98% by weight or more, preferably 98.5% by weight or more, more preferably 99% by weight or more. When the propylene content in the copolymer is 98
If the amount is less than the weight percentage, the stiffness of the obtained film tends to be insufficient when the propylene-based polymer is used.

The propylene polymer of the present invention has a melt flow rate (MFR: 230 ° C., 21.18 N) of 0.1.
It is in the range of 5 to 20, preferably 1 to 15 (dg / min). When the MFR is in the above range, a film having excellent antistatic performance and high rigidity can be obtained.

The propylene polymer of the present invention has an isotactic pentad fraction [mmmm] of 0.89 to 0.95, which is an index of the stereoregularity of polypropylene,
More preferably, it is in the range of 0.90 to 0.94. [Mmmm] is A. Zambel (A. Zambelli)
et al., Macromolecules Volume 8 (Macromolecul)
es Volume 8), 687-689 (1975). When [mmmm] is less than 0.89, the antistatic performance of the obtained film is improved, but the rigidity of the film is reduced. When [mmmm] exceeds 0.95, the film has high rigidity, but the antistatic effect is reduced. Here, the antistatic effect and the antistatic performance refer to the surface specific resistance of the film when an antistatic agent is added, and the smaller the surface specific resistance, the greater the antistatic effect and the better the antistatic performance.

The propylene polymer of the present invention has a boiling pentane extraction ratio (C5-Ext) of 0.5% by weight or more, a boiling heptane extraction ratio (C7-Ext) of 5% by weight or less, and (C7 −Ext)> 3.5 × (C5-Ex
t). (C5-Ext)
Is less than 0.5% by weight, the antistatic performance deteriorates and C7
If -Ext) exceeds 5% by weight, the rigidity of the resulting film decreases. If (C7-Ext) is at most 3.5 times (C5-Ext), the low molecular weight component in the copolymer will be excessive, and the rigidity of the resulting film will decrease.

The propylene-based polymer of the present invention has a weight-average molecular weight of 7 × 10 ⁴ or more of a soluble component at 0 ° C. or less and a weight-average molecular weight of a soluble component at 50 ° C. or less of 6 × 10 6 by a cross fractionation method. 10 ⁴ or more. The weight-average molecular weight of the soluble component at 0 ° C. or less by the cross fractionation method is less than 7 × 10 ⁴ or 5
If the weight-average molecular weight of the soluble component at 0 ° C. or lower is less than 6 × 10 ⁴ , problems such as a decrease in the rigidity of the obtained film occur.

Here, the cross fractionation method includes a temperature rise elution fractionation method (TREF) and gel filtration chromatography (G
(PC) method, and the crystallinity distribution and molecular weight distribution of the polymer can be simultaneously known. That is, a high-temperature sample solution in which a propylene-based polymer is completely dissolved in ortho-dichlorobenzene is injected into a column filled with an inert carrier such as glass beads, and the temperature of the column is lowered to fill the sample with a filler. After adhering to the surface, the temperature of the column is gradually increased while flowing ortho-dichlorobenzene through the column, and the concentration of the propylene-based polymer eluted at each temperature is detected. This is a method in which the eluted components are sent to a GPC apparatus online for each fraction, and the molecular weight distribution and molecular weight of each component are calculated from the obtained chromatogram. Since the elution temperature increases as the crystallinity of the eluted component increases, the distribution of the crystallinity of the polymer can be known by determining the relationship between the elution temperature and the amount of elution of the polymer (% by weight).

In the above method, the rate of decrease in the column temperature is the rate required for crystallization of the crystalline component contained in the propylene-based polymer of the sample at each temperature, and the rate of increase in the temperature of the column is It is necessary to adjust the rate at which the dissolution of the eluted components at the temperature can be completed, and such a rate of decreasing and increasing the column temperature is determined by preliminary experiments.

(1) A method for producing the propylene-based polymer of the present invention. The method for producing the propylene-based polymer of the present invention is not particularly limited as long as the obtained propylene-based polymer satisfies the above-mentioned various properties, but the following method can be exemplified. That is, using a catalyst system comprising a solid catalyst component (A) containing magnesium, titanium, halogen and an electron donating organic compound as essential components, an organic aluminum compound (B) and an electron donating organic silicon compound (C), Alternatively, it is a method of (co) polymerizing propylene with another olefin.

The solid catalyst component (A) is a catalyst component for olefin polymerization in which a titanium halide is supported on a carrier whose main component is a Mg compound precipitated from a solution, and is produced by the following method. Can be. General formula Mg
(OR ¹ ) _n (OR ² ) _2-n or MgR ³ _m (OR ⁴ ) _2-m
(Where R ¹ , R ² , R ³ and R ⁴ are each independently an alkyl group having 3 to 20 carbon atoms, an aryl group, or an aromatic group having 5 to 20 carbon atoms, and m and n are In the presence of carbon dioxide, a magnesium compound represented by the formula: R ⁵ OH (where R ⁵ is a saturated or substituted carbon atom having 1 to 20 carbon atoms) A monohydric alcohol or polyhydric alcohol represented by the formula (1), which is an unsaturated alkyl group) in an inert hydrocarbon solvent to obtain the component (a).

The obtained component (a) has the general formula: TiX_p
(OR⁶)_4-p(Where X is chlorine (Cl), bromine (B
r) or iodine (I);⁶Is carbon number 1-2
0 alkyl group, aryl group or C 3-20
A cycloalkyl group, and P is an integer of 1 to 4).
And a general formula SiX_q(OR⁷)
_4-q(Where X is Cl, Br or I;⁷Is charcoal
An alkyl group, an aryl group, or a carbon atom having a prime number of 1-20
And q is an integer of 1 to 4.
Halogenated silane, Si-O-Si bond
Or a siloxane compound having a siloxane compound
Object and general formula R⁸ _sSi (OR⁹)_4-s(Where R⁸and
R⁹Is independently an alkyl group having 1 to 20 carbon atoms,
An aryl group or a cycloalkyl group having 3 to 20 carbon atoms
And S is an integer of 1 to 4).
Is mixed with the mixture and reacted to obtain a solid product (I)
Get.

The solid product (I) is a monohydric or polyhydric alcohol represented by the general formula R ¹⁰ OH, wherein R ¹⁰ is a saturated or unsaturated alkyl group having 1 to 20 carbon atoms. And a cyclic ether to dissolve and reprecipitate to obtain a solid product (II). The solid product (I
I) is reacted with a component (b) comprising a titanium halide represented by the general formula TiX _p (OR ⁶ ) _4-p to obtain a solid component (III). b)
Reacting a mixture of the compound and an electron donating compound (IED) to obtain a solid product (IV). The solid product (IV) thus obtained is converted into the solid catalyst component (A)
Can be exemplified.

The electron donating compound (IED) includes alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, acid anhydrides. And organic silicon compounds such as dialkoxysilane and trialkoxysilane.

More specifically, methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, phenol, cresol, naphthol, acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, acetaldehyde, propionaldehyde, octyl aldehyde, Benzaldehyde, naphthaldehyde, methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, cellosolve acetate, ethyl propionate, methyl butyrate, ethyl valerate,
Ethyl stearate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, butyl benzoate, propyl benzoate, octyl benzoate, cyclohexyl benzoate, benzoate Phenyl acid, benzyl benzoate, ethyl toluate, methyl toluate, amyl toluate, ethyl benzoate, methyl anisate, γ-butyrolactone, α-valerolactone, coumarin, phthalide, diethyl phthalate, dibutyl phthalate, phthalate Dimethyl phthalate, diphthalic acid
2-ethylhexyl, dioctyl phthalate, diheptyl phthalate, di-iso-propyl phthalate, dipropyl phthalate, dimethyl phthalate, succinic anhydride, benzoic anhydride,
Ethyl silicate,

Dimethyldimethoxysilane, diethyldimethoxysilane, dipropyldimethoxysilane, diisopropyldimethoxysilane, dibutyldimethoxysilane,
Diisobutyldimethoxysilane, di-t-butyldimethoxysilane, dicyclopentyldimethoxysilane, dicyclohexyldimethoxysilane, methylethyldimethoxysilane, methylpropyldimethoxysilane, methylisopropyldimethoxysilane, methylisobutyldimethoxysilane, methylcyclopentyldimethoxysilane, methylcyclohexyldimethoxysilane , Dialkoxysilanes such as isopropylisobutyldimethoxysilane,
Methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isopropyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, etc. And the like trialkoxysilane. Two or more of these electron donors (IEDs) can be used in combination.

As the organoaluminum compound (B),
Examples thereof include trialkylaluminums such as triethylaluminum, triisobutylaluminum, and trihexylaluminum, and dialkylaluminum halides such as a diethylaluminum halide, and further, a mixture of a trialkylaluminum and a dialkylaluminum halide. Preferred examples of the organoaluminum compound (B) include triethylaluminum and triisobutylaluminum.

Examples of the electron donating organic silicon compound (C) include tetraalkoxysilanes such as tetraethoxysilane and tetrapropoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, dipropyldimethoxysilane, dibutyldimethoxysilane, diisobutyldimethoxysilane, Dicyclopentyldimethoxysilane,
Methyl ethyl dimethoxy silane, methyl propyl dimethoxy silane, methyl isopropyl dimethoxy silane, methyl isobutyl dimethoxy silane, methyl cyclopentyl dimethoxy silane, methyl cyclohexyl dimethoxy silane, dimethyl diethoxy silane, diethyl diethoxy silane, dipropyl diethoxy silane, dibutyl ethoxy silane, Diisobutyldiethoxysilane, t-butylmethyldiethoxysilane,

Dicyclopentyldiethoxysilane, methylethyldiethoxysilane, methylpropyldiethoxysilane, methylisopropyldiethoxysilane, methylisobutyldiethoxysilane, methylcyclopentyldiethoxysilane, methylcyclohexyldiethoxysilane, isopropylisobutyldimethoxysilane, etc. Dialkoxysilanes,

Methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, butyltrimethoxysilane, butyltrimethoxysilane Ethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, octyltrimethoxysilane, octyltri Trialkoxy such as ethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane Silanes can be exemplified.

Of these, diisobutyldimethoxysilane, isopropylisobutyldimethoxysilane, diisobutyldiethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, isopropyltrimethoxysilane, isopropyltrimethoxysilane, isopropyltrimethoxysilane Examples include ethoxysilane, isobutylmethyldimethoxysilane, isobutylmethyldiethoxysilane, ethyltriethoxysilane, ethyltrimethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, pentyltriethoxysilane, and pentyltrimethoxysilane. These electron donating organic silicon compounds (C)
Two or more types can be used in combination.

In the polymerization method for producing a propylene polymer according to the present invention, the solid catalyst component (A) is prepared by adding a trace amount of α-olefin such as ethylene or propylene to the solid catalyst component (A) prior to the main polymerization. ) Is preferably used in a state where the α-olefin polymer is supported on the solid catalyst component (A) by a preliminary polymerization treatment. The preliminary polymerization treatment can be performed using the solid catalyst component (A) and the organoaluminum compound (E).

As the organoaluminum compound (E), the above-mentioned organoaluminum compound (B) can be used. Even if the organoaluminum compound (B) and the organoaluminum compound (E) are of the same kind, May be used. Preferred examples of the organoaluminum compound (E) include triethylaluminum and triisobutylaluminum.

In the prepolymerization treatment, an electron-donating organic silicon compound (D) can be used if necessary. The electron donating organic silicon compound (C) described above can be used as the electron donating organic silicon compound (D).
The electron donating organic silicon compound (D) and the electron donating organic silicon compound (C) may be the same or different.

Preferred electron-donating organosilicon compound (D)
As diisobutyldimethoxysilane, diisobutyldiethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, isobutylmethyldimethoxysilane, isobutylmethyldiethoxysilane Examples thereof include silane, ethyltriethoxysilane, ethyltrimethoxysilane, butyltriethoxysilane, and pentyltriethoxysilane. These organic silicon compounds can be used as a mixture of two or more kinds.

In the prepolymerization treatment, a hydrocarbon solvent inert to the prepolymerization reaction is used. Examples of the hydrocarbon solvent include propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, benzene and toluene. Can be illustrated.

The proportions of the respective catalyst components used in the prepolymerization treatment are as follows: the titanium atom (Ti) in the solid catalyst component (A), the aluminum atom (Al) in the organoaluminum compound (E), and the electron-donating organosilicon compound. (D) silicon atom (S
the proportion of i) is 1000> Al / Ti>0.05;
100> Al / Si> 0.05, preferably 300> Al / Ti>0.1;60> Al / Si>
From the range of 0.1, more preferably 50> Al / Ti>
0.5; 40> Al / Si> 0.8.

The concentration of the solid catalyst component (A) in the hydrocarbon solvent is 0.05 to 30% by weight, preferably 0.1 to 15%.
%, More preferably in the range of 0.5 to 8% by weight.

The reaction temperature of the prepolymerization treatment is -10 to 90 ° C.
, Preferably 0 to 60 ° C, more preferably 5 to 4 ° C.
It can be performed in the range of 0 ° C.

The α-olefin used in the prepolymerization treatment includes ethylene and propylene, 1-butene,
Α-olefins such as hexene can be used. Preferred are ethylene and propylene, and more preferred is propylene. The amount of the α-olefin to be prepolymerized by the prepolymerization treatment depends on the amount of the solid catalyst (A) 1
g to 0.05 to 100 g, preferably 0.05
-30 g, more preferably 0.1-10 g.

The method of supplying each catalyst component into the hydrocarbon solvent during the prepolymerization treatment may be either simultaneous supply of (A), (E) or (D) or separate supply. . Further, in the catalyst subjected to the prepolymerization treatment, the solvent used in the prepolymerization treatment may be decanted and replaced with the same solvent or a different solvent from the solvent used in the prepolymerization treatment.

The main polymerization is carried out using propylene or propylene and an olefin other than propylene as a monomer material. Examples of the polymerization method include a slurry polymerization method and a solution polymerization method in which propylene is polymerized using a hydrocarbon solvent.
Any of a bulk polymerization method in which propylene itself used for polymerization is used as a liquefied propylene as a dispersion medium and a gas phase polymerization method in which propylene gas does not use a dispersion medium can be used. Legal is used. When using the slurry polymerization method, after decanting the solvent used for the pre-polymerization treatment, the main polymerization is performed using the same solvent as the solvent used for the pre-polymerization treatment or a solvent different from the solvent used for the pre-polymerization treatment. You may.

The ratio of each catalyst component used in the main polymerization is in the following range. Titanium atom in solid catalyst component (A)
Aluminum atom in organoaluminum compound (B) and organoaluminum compound (E) with respect to (Ti)
The ratio of the total amount of (Al) is selected from a range of 700> Al / Ti> 5, preferably a range of 500> Al / Ti> 10, and more preferably a range of 300> Al / Ti> 10.

Titanium atom (Ti) in the solid catalyst component (A)
For the silicon atom in the electron-donating organosilicon compound (C)
The ratio of (Si) is in the range of 300> Al / Si> 0.1, preferably in the range of 100> Al / Si> 0.51, and more preferably in the range of 60> Al / Si> 1. (The silicon atom (Si) in the electron donating organic silicon compound (D) used in the prepolymerization is excluded from the calculation).

When two or more kinds of the electron donating organic silicon compounds (C) are used, they can be added so as to have the same molar ratio to each electron donating organic silicon compound.

The supply of the solid catalyst component (A), the organoaluminum compound (B) and the electron-donating organosilicon compound (C) to the propylene polymerization system in the main polymerization is as follows:
(A), (B) and (C) can be supplied simultaneously or separately.

The main polymerization can be carried out at an industrially suitable polymerization temperature and polymerization pressure, although the polymerization conditions vary depending on the polymerization method selected. For example, the polymerization temperature is 0
To 100 ° C, preferably 20 to 90 ° C, more preferably 30 to 85 ° C.
In the slurry polymerization method, in the slurry polymerization method, the propylene partial pressure in the gas phase is in the range of 0.01 to 105 MPa (gage pressure), preferably in the range of 0.1 to 1.3 MPa (gage pressure). Preferably, it can be in the range of 0.3 to 1.2 MPa (gage pressure). In the bulk polymerization method, the propylene partial pressure in the gas phase is basically determined by the polymerization temperature. Also,
In the gas phase polymerization method, the propylene partial pressure is 0.1 to 3.5 MPa.
(Gage pressure) (range, preferably 0.5 to 3.0 MP
a (gauge pressure) range, more preferably 1 to 2.8MPa
a (gage pressure).

In the present polymerization, a molecular weight regulator can be appropriately used for the purpose of adjusting the molecular weight of the obtained propylene polymer. Hydrogen can be suitably used as a molecular weight regulator, that is, a chain transfer agent. Further, the polymerization can be performed by arranging several polymerization vessels in series.
At this time, the polymerization conditions for each polymerization vessel may be the same or different.

In the main polymerization, propylene is homopolymerized or propylene is replaced with ethylene as another olefin.
An unsaturated hydrocarbon selected from 1-butene, 1-pentene, 1-hexene, 1-octene and the like is copolymerized. In the case of using the slurry polymerization method and the bulk polymerization method, the components (soluble polymers) dissolved in the hydrocarbon solvent or liquefied propylene can be removed from the propylene-based polymer. Is also possible. In this way, the propylene-based polymer of the present invention which satisfies the requirements (1) to (1) is obtained.

(3) Polypropylene Film The propylene-based polymer of the present invention can be obtained by molding a biaxially oriented polypropylene film by a conventionally known film forming method, such as a tenter method for performing sequential stretching or a tubular method for performing simultaneous biaxial stretching. It can be suitably used as a raw material. Hereinafter, a method for producing a polypropylene film using the propylene-based polymer of the present invention will be specifically described using a tenter method as an example.

Additives such as an antistatic agent and, if necessary, an antioxidant, a light-proofing agent, a weatherproofing agent, a lubricant, an anti-blocking agent, and a coloring agent are added to the propylene-based polymer within a range that does not impair the effects of the present invention. In addition, a polypropylene composition is made. Usually, the composition is pelletized by an extruder or the like.

As the antistatic agent, known antistatic agents can be used. Examples of the antistatic agent include an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, and a surfactant mixture.

Examples of the anionic activator include fatty acid salts, higher alcohol sulfates, liquid fatty oil sulfates, sulfates of aliphatic amines and aliphatic amides, sulfonates of dibasic fatty acid esters, and alkylallyl sulfonic acids. Examples thereof include salts and formalin-condensed naphthalene sulfonates.

Examples of the cationic activator include aliphatic amine salts, quaternary ammonium salts, and alkylpyridinium salts. Examples of the nonionic surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenol ethers, polyoxyethylene alkyl esters, sorbitan alkyl esters, and polyoxyethylene sorbitan alkyl esters. Examples of the amphoteric activator include imidazoline derivative forms, higher alkylamino forms (pentane forms), sulfate and phosphate esters, and sulfonic acid forms.

Examples of the surfactant mixture include anionic mixed type, cationic mixed type, nonionic mixed type, anionic and nonionic mixed type, and cationic and nonionic mixed type.

The polypropylene composition melted by the extruder is extruded into a plate shape from a T-die, cooled and solidified on a cooling roll, and then the plate-shaped molded product is heated in a longitudinal direction (extruder shaft) by a heated roll. Direction: Hereinafter, this direction may be referred to as “longitudinal direction”) to obtain a uniaxially stretched film. Next, the obtained uniaxially stretched film is guided into a tenter, stretched in a lateral direction (a direction perpendicular to an extruder axis: hereinafter, this direction may be referred to as “lateral direction”) through a preheating unit, and wound up. The polypropylene film of the present invention is obtained.

In the tenter method, the melting temperature of the polypropylene composition in the extruder is in the range of 200 to 300 ° C., preferably in the range of 220 to 280 ° C. It is preferable that the preheating temperature in the longitudinal stretching is 110 to 160 ° C, the longitudinal stretching temperature is 110 to 160 ° C, and the longitudinal stretching ratio is 3.0 to 9.0 times. The preheating temperature in the transverse stretching is 160 to 200 ° C, and the transverse stretching temperature is 14
The range is 0 to 170 ° C., and the transverse stretching ratio is 3.0 to 1.
It is preferably set to 1.0 times.

The use of the propylene polymer of the present invention as a raw material makes it possible to form a biaxially stretched film at high speed and high efficiency by the above tenter method. The obtained film can be subjected to stress relaxation by heat treatment, and printability and vapor deposition properties can be improved on the film surface by corona treatment, flame treatment, and the like, if necessary.

The film of the present invention includes not only a single-layer film itself, but also a laminated film laminated with another film and a metal-deposited film obtained by further performing metal deposition on the surface.

[0054]

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. The measuring methods of each physical property value used in Examples and Comparative Examples are shown below.

(I) Isotactic pentad fraction ¹³ C-NMR measurement apparatus (GSX-27 manufactured by JEOL Ltd.)
0 type). A. Zambelli et a
l., Macromolecules Vol. 8
me 8), page 687-689 (1975).

(Ii) Melt flow rate (dg / min) The method described in JIS K7210 (condition 14: 230)
C., 21.18 N).

(Iii) Young's modulus (MPa) MD (vertical direction) from biaxially stretched polypropylene film
And TD (horizontal direction) in each direction, width 10 mm,
A test piece having a length of 150 mm was cut out and subjected to ASTM D-88.
According to the method described in 2, the Young's modulus was measured at a chuck-to-chuck distance of 50 mm and a tensile speed of 5 mm / min.

(Iv) Heat shrinkage (%) From the biaxially stretched polypropylene film, a length (L ₀ ) of 20 cm × a width of 1 cm in (vertical direction) and (lateral direction), respectively.
Was cut out, and each test piece was heated in an oven at 140 ° C. for 15 minutes, and then each length (L ₁ , unit c)
m), and the shrinkage ratio (S
%). S = 100 × (L ₀ −L ₁ ) / L ₀

(V) Cross fractionation method A CFC device manufactured by Mitsubishi Chemical Corporation (T150A type, detector: infrared detector, measurement wavelength: 3.41 μm, column: 4.
The measurement was carried out under the following conditions using 6φm × 150 mm, filler: glass beads (Shodex GPC AD-806MS manufactured by Showa Denko). The sample solution (solvent: ortho-dichlorobenzene, sample concentration: 4) was added to the column heated to 40 ° C.
After injection of 4 mL (0 mg / 10 mL), the sample polymer was cooled to 0 ° C. at a rate of 60 ° C./hour, and the sample polymer was adsorbed (precipitated) on the surface of the filler. At this time, the components which did not adsorb to the filler surface and were dissolved in the solvent were sent as soluble components at 0 ° C. or lower to a GPC column online, and after molecular weight fractionation, the elution amount was detected by an infrared detector. Then, the column was gradually heated to 50 ° C. while flowing ortho-dichlorobenzene at a flow rate of (60 ml / h), and the polymer eluted from the filler surface at each temperature was sequentially sent to the GPC column online. After the molecular weight fractionation, the elution amount was detected with an infrared detector. The soluble component of 50 ° C. or lower means the total amount of soluble components up to 50 ° C. including the soluble component of 0 ° C. or lower, and integrating the results obtained at each step temperature increase up to the temperature. I asked for it.

(Vi) Boiling pentane extraction ratio and boiling heptane extraction ratio A sheet obtained by pressing a propylene-based polymer at 230 ° C. and 10 MPa was cut into small pieces of about 3 cm × 3 cm by a cutter. About 50 g of the obtained strip was ground for about 20 minutes using a Willet grinder (Ikeda: W140).
2 g of this pulverized product was subjected to Soxhlet extraction (solvent 150 m
L; pentane or heptane, extraction time: 3h). The extraction residue was vacuum dried at 80 ° C. for 2 hours when pentane was used, and 3 hours when heptane was used, allowed to cool in a desiccator for 1 hour, weighed, and the extraction rate was calculated.

(Vii) Surface resistivity A sample film (8 cm × 8 cm) was aged at 40 ° C. for 2 days.
After applying a voltage of V for 2 minutes, it is left for 1 minute. Immediately after this, the surface resistivity of the film was measured (2 days after aging at 40 ° C.). Subsequently, the film was aged at 40 ° C. for 3 days (5 days in total), and a voltage of 500 V was applied for 2 days.
After applying for 1 minute, it was left for 1 minute and the surface resistivity was measured. The measuring device is R83 manufactured by Advantest
A 40A-Ultra high resistance meter was used.

Example 1 (1) Synthesis of Solid Catalyst Component (A) A 30-liter autoclave equipped with a stirrer, a pressure gauge and a thermometer and substituted with high-purity nitrogen (hereinafter, liter is referred to as L) was placed in an autoclave. 2.3 kg of magnesium ethoxide,
4.15 L of 2-ethyl-1-hexanol and 16.5 L of toluene were added. 0.2 MPa
Under a carbon dioxide gas atmosphere (hereinafter referred to as a gauge pressure), the mixture was heated to 90 ° C. and stirred at 150 rpm for 3 hours.
Cool the obtained solution, degas the carbon dioxide gas, and
(a) was obtained. This solution contained 0.1 g / L magnesium ethoxide. The above operations were handled under atmospheric pressure.

Stirrer, thermometer, condenser, nitrogen sea
15L autoclave equipped with line and baffle
Into a tube (baffle ratio 0.15), toluene 3L, Ti
Cl _Four190 mL, hexamethyldisiloxane 250 m
L, and mixed at room temperature for 5 minutes at 250 rpm.
Thereafter, 1.5 L of the solution (a) was charged for 10 minutes. After input
Immediately, solid particles (I) were precipitated. The solid particles (I)
Add 30 mL of ethanol and tetrahydrofura to the solution
(THF) 0.5L and stirring at 150 rpm.
When the temperature was raised to 60 ° C within 15 minutes while maintaining
Once the solid particles (I) have dissolved, then within 15 minutes
Solid particles began to precipitate again. The formation of these solid particles is 1
Finished within 0 minutes. Stir at 60 ° C for 45 minutes
After the continuation, the stirring was stopped and the resulting solid (II) was settled.
I let it. The supernatant is removed by decantation and the remaining
The solid (II) was washed twice with 2 L of toluene.

The obtained solid product (II) was mixed with toluene 2
L and 1 L of TiCl ₄ were added, and the temperature was raised to 135 ° C. within 20 minutes while stirring at 250 rpm, and this temperature was maintained for 1 hour. The stirring was stopped, and the resulting solid (III) was allowed to settle, and the supernatant was removed by decantation. 1 L of TiCl ₄ , 2.5 L of toluene and 21 mL of diisobutyl phthalate were added to the resulting solid (III),
And stirred at 250 rpm for 1.5 hours. The supernatant was removed by decantation, ₂ L of TiCl ₄ was added to the residue, and the mixture was refluxed for 10 minutes with stirring. The supernatant was removed by decantation, and the residue was washed three times with 2 L of toluene and four times with 2 L of hexane to obtain 116 g of a solid catalyst component (A). This solid catalyst component (A)
Contained 17.3% by weight of magnesium, 2.3% by weight of titanium, 55.6% by weight of chlorine, and 8.6% by weight of diisobutyl phthalate.

(2) Pre-polymerization treatment A stirrer was equipped, and the internal volume was replaced with high-purity nitrogen.
20 L of hexane, 100 g of the solid catalyst component (A), 0.1 mol of triethylaluminum, and 0.015 mol of diisobutyldimethoxysilane were added to a L stainless steel reactor. While stirring at 30 ° C. and a stirring rotation speed of 200 rpm, propylene gas was introduced and pressurized until the propylene partial pressure became 0.1 MPa, and a prepolymerization treatment was performed for 6 hours. Thereafter, propylene gas was purged. The amount of polymerized propylene was 3 g per 1 g of the solid catalyst component (A).

(3) Main Polymerization Equipped with a stirrer, the internal volume of
In a 0 L stainless steel reactor, 0.5 g / h of the pre-polymerized solid catalyst component (A) was used as the solid catalyst component, 0.018 mol / h of triethylaluminum, and 0.003 mol / h of diisobutyldimethoxysilane.
, And each was continuously supplied. At the same time, polymerization temperature 70
Propylene was continuously supplied so that the polymerization pressure was maintained at 2.3 MPa under the condition of
Hydrogen is continuously supplied so that the propylene molar ratio becomes 0.003, and continuous gas phase polymerization of propylene is performed.
A powdery propylene-based polymer was obtained at a production rate of 15 kg / h.

(4) Granulation (Production of Polypropylene Composition) To 100 parts by weight of the obtained powdery propylene polymer, tetrakis- [methylene-3- (3 ′,
5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane 0.10 parts by weight, tris (2,4-di-t
0.10 parts by weight of -butylphenyl) phosphite, 0.05 parts by weight of calcium stearate, and alkyldiethanolamine fatty acid ester, glycerin fatty acid ester and alkyldiethanolamine as antistatic agents in a total of 1 part by weight. Then, the mixture was uniformly mixed with a Henschel mixer (trade name). The obtained mixture was melt-kneaded at an extrusion temperature of 230 ° C. using an extruder having a diameter of 65 mm and a cylinder-length / diameter ratio (L / D) of 30 to obtain a pellet-shaped polypropylene composition.

(5) Film Formation The polypropylene composition in the form of pellets was extruded at 250 ° C. using an extruder equipped with a T-die and taken up by a cooling roll at 30 ° C. to obtain a polypropylene plate-like molded product. Next, the plate-like molded product was stretched at a stretching temperature of 145 ° C. by a tenter-type sequential stretching apparatus.
The film is stretched 5 times in the machine direction in the longitudinal direction, and then stretched 10 times in the transverse direction in a tenter at a temperature of 160 ° C. in the bath of the stretching zone, and further subjected to an 8% stress relaxation treatment at 170 ° C.
A biaxially stretched polypropylene film having a thickness of 20 μm was obtained.

(6) Evaluation The polypropylene and the biaxially oriented polypropylene film thus obtained were subjected to the above (i) to (vi).
Physical properties of i) were measured. The results are shown in Tables 1, 2 and 3. Table 1 shows isotactic pentad fraction [mmmm] of polypropylene, boiling pentane extraction rate, boiling heptane extraction rate, ethylene content, and melt flow rate. Table 2 shows analysis results by the cross fractionation method. Table 3 shows the results of measuring various physical properties of the biaxially stretched polypropylene film.

Comparative Example 1 A solid catalyst component (A) was obtained according to the method described in Example 1, (1). The pre-polymerization treatment is performed in the same manner as in Example 1 (2).
Was carried out in accordance with Example 1, except that diisopropyldimethoxysilane was used in place of diisobutyldimethoxysilane used in Example 1. In the main polymerization, the hydrogen / propylene molar ratio of 0.003 in Example (3) was changed to 0.005.
The procedure was performed in the same manner as in Example 1 except that diisobutyldimethoxysilane was used instead of diisobutyldimethoxysilane, to obtain a powdery propylene-based polymer at a production rate of 14 kg / h. Granulation and film formation were performed according to Example 1. The physical properties of the propylene polymer and the biaxially stretched polypropylene film thus obtained are shown in Tables 1, 2 and 3.

Example 2 A solid catalyst was prepared according to the method described in Example 1 except that a mixture of 16 mL of diisobutyl phthalate and 6 mL of dinormal octyl phthalate was used instead of 21 mL of diisobutyl phthalate used in (1) of Example 1. The component (A) was obtained. The pre-polymerization treatment was performed by the method described in Example 1 (2). The main polymerization was carried out by the method described in (3) of Example 1 except that the hydrogen / propylene ratio was changed to 0.0025 to obtain a powdery propylene-based polymer at a production rate of 15 kg / h. Granulation and film formation were performed according to Example 1. The physical properties of the propylene polymer and the biaxially stretched polypropylene film thus obtained are shown in Tables 1, 2 and 3.

Example 3 According to the method described in Example 1, the production of the solid catalyst component (A) and the preliminary polymerization treatment were carried out. The main polymerization was carried out in accordance with Example 2 except that the hydrogen / propylene molar ratio was 0.003 and an ethylene / propylene mixed gas having an ethylene / propylene molar ratio of 0.0015 was used instead of propylene. As a result, a powdery propylene-based polymer was obtained at a production rate of 15.5 kg / h. Granulation and film formation were performed according to Example 1. The physical properties of the propylene-based polymer and the biaxially oriented polypropylene film thus obtained are shown in Tables 1, 2 and 3.

Example 4 According to the method described in Example 2, the production of the solid catalyst component (A) and the preliminary polymerization treatment were carried out. In this polymerization, the hydrogen / propylene molar ratio is set to 0.0025, and ethylene / propylene having a molar ratio of ethylene / propylene of 0.001 is used instead of propylene.
Except that a propylene mixed gas was used, the procedure was performed in the same manner as in Example 2 to obtain a powdery propylene-based polymer at a production amount of 16 kg / h. Granulation and film formation were performed according to Example 1. The physical properties of the propylene polymer and the biaxially oriented polypropylene film thus obtained are shown in Table 1,
The results are shown in Tables 2 and 3.

Comparative Example 2 In the main polymerization of Comparative Example 1, an ethylene / propylene mixed gas having a hydrogen / propylene molar ratio of 0.004 instead of 0.005 and an ethylene / propylene molar ratio of 0.0017 instead of propylene was used. A powdered polypropylene was obtained at a production rate of 16.1 kg / h according to Comparative Example 1, except that Granulation and film formation were performed according to Example 1.
The physical properties of the thus obtained polypropylene and biaxially oriented polypropylene films are shown in Tables 1, 2 and 3.

Example 5 In the main polymerization of Example 4, the molar ratio of hydrogen / propylene was 0.0025, and the molar ratio of ethylene / propylene was 0.1.
15.9 kg / h according to the method described in Example 4, except that an ethylene / propylene mixed gas of 001 was used.
The powdery polypropylene was obtained with the production amount. Granulation and film formation were performed according to the method described in Example 1. The physical properties of the thus obtained polypropylene and biaxially oriented polypropylene films are shown in Tables 1, 2 and 3.

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

[Table 3]

[0079]

According to the present invention, a practically sufficient antistatic performance can be obtained by adding a small amount of an antistatic agent, as compared with the case of using a conventional propylene polymer. Excellent antistatic performance can be obtained with the same amount of antistatic agent as the conventional propylene-based polymer,
In addition, a highly rigid polypropylene film can be obtained.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Ando 3-27-2, Tatsumidaihigashi, Ichihara-shi, Chiba Prefecture (72) Inventor Shinji Nakata 2--17-17, Tatsumidaihigashi, Ichihara-shi, Chiba Prefecture (72) Inventor, Naoshin Minamizawa 4-100 Shinjo, Nonoichi-machi, Ishikawa-gun, Ishikawa-gun Famiruyuit 202 F-term (reference) 4F071 AA15 AA15X AA20 AA20X AA21 AA21X AA51 AC09 AC10 AC12 AC13 AC14 AC19 AE16 AH04 4J002 BB121 EU046 EV 136151 BB151 EU046 EW046 FD102 FD106 GG02 4J100 AA02Q AA03P AA04Q AA07Q AA19Q CA01 CA04 DA40 DA41 DA42 JA58

Claims (2)

[Claims] 1. A propylene polymer having the following characteristics: A propylene homopolymer or a copolymer of propylene and one or more olefins selected from ethylene and α-olefins having 4 or more carbon atoms, wherein the propylene content in the copolymer is 98% by weight or more. Certain propylene-olefin copolymers. Melt flow rate (MFR: 230 ° C, 21.18)
N) is in the range of 0.5 to 20 (dg / min). Isotactic pentad fraction [mmmm] is 0.
It is in the range of 89 to 0.95. Boiling pentane extraction rate (C5-Ext) is 0.5% by weight
As described above, the boiling heptane extraction rate (C7-Ext) is 5% by weight or less, and (C7-Ext)> 3.5 · (C5
-Ext). The weight-average molecular weight of the soluble component at 0 ° C. or less by cross fractionation is 7 × 10 ⁴ or more, and the weight-average molecular weight of the soluble component at 50 ° C. or less is 6 × 10 ⁴ or more. 2. A film formed by forming a polypropylene composition obtained by adding an antistatic agent to the propylene-based polymer according to claim 1.