JPH0730132B2 - Propylene random copolymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a propylene random copolymer produced from propylene, ethylene and 1-butene.

More specifically, it has excellent heat-sealing property, heat-sealing property, transparency, and blocking property, has a small hydrocarbon-soluble content, and has a narrow composition distribution.
A propylene-based random copolymer produced from butene.

[Prior Art] Polypropylene has been used for a wide range of applications because of its excellent physical properties. For example, it is widely used in the field of packaging films, but in order to improve heat sealability at low temperatures in this type of application, ethylene is usually copolymerized in an amount of about 1 to 5% by weight, and propylene / ethylene copolymer It is generally provided as a united body. The polypropylene film modified as described above has the advantage that it is superior in transparency and scratch resistance as compared with the low-density polyethylene film that is also used as a packaging film, but is still inferior in heat sealability at low temperatures. It is connected. There is a method to further increase the copolymerization amount of ethylene in order to further improve the heat-sealing property, but in this case, the production rate of the soluble copolymer having no utility value is increased, and the yield of the target copolymer is increased. There is a disadvantage that Moreover, in the slurry polymerization, the slurry properties during the polymerization may be deteriorated and the polymerization may be difficult.

In order to avoid such disadvantages, a method of copolymerizing ethylene and α-olefin having 4 or more carbon atoms into propylene using a conventional titanium trichloride catalyst is disclosed in JP-A-49-354.
87, JP-A-51-79195 and JP-A-52-16588. According to these proposals, it can be said that the production ratio of the solvent-soluble polymer is reduced as compared with the case where the binary copolymerization of propylene and ethylene is carried out. The production ratio of the solvent-soluble polymer is large, and as the copolymerization amount of ethylene and / or α-olefin of C ₄ or more increases, the tendency becomes even larger.

The present inventors have compared with the titanium trichloride-based catalyst in the above proposal, a specific solid titanium catalyst component, an organometallic compound catalyst component, and a solvent-soluble polymer that have substantially the same production ratio in propylene homopolymerization, When a supported catalyst formed from an electron donor catalyst component is used for the copolymerization of propylene, ethylene, and α-olefin having 4 or more carbon atoms, it is expected to be larger than the case of using the titanium trichloride-based catalyst in the above proposal. In addition, it was found that the soluble polymer can be further reduced, and the yield of the target copolymer and the catalyst efficiency can be remarkably excellent. Therefore, it was proposed in JP-A-54-26891. . Although a remarkable improvement was observed by using the catalyst specifically disclosed in this publication, in the case where a copolymer having a considerably high ethylene content was to be produced, a slurry resulting from porridge-like polymer formation was obtained. It is difficult to continue the polymerization due to deterioration of properties,
The problem remains that the solid polymer cannot be obtained in a sufficiently high yield. If the ethylene content cannot be increased to obtain a copolymer having a low melting point, α- having 4 or more carbon atoms
Although there is only a method of increasing the content of olefin, the effect of lowering the melting point is smaller in α-olefin, and since the rate of copolymerization is slower, a method of increasing the content of α-olefin more than necessary is a good idea. That was not the case.

Further, the inventors of the present invention disclosed in JP-A-59-47210, propylene suitable for film use with excellent heat sealability,
A method has been proposed in which a copolymer of ethylene and α-olefin having 4 or more carbon atoms can be obtained in a high yield and a high yield while reducing the disadvantageous by-product of the soluble copolymer. However, the copolymer obtained by this method is not necessarily sufficient in heat-sealing property, heat-sealing property, transparency, and anti-blocking property, and the hydrocarbon-soluble content is not so small as to be sufficiently satisfied.

[Problems to be Solved by the Present Invention] Accordingly, the present invention provides a heat-sealing property produced from propylene, ethylene and 1-butene, a heat-sealing property,
It is an object of the present invention to provide a propylene random copolymer which is excellent in transparency and blocking resistance and has a low hydrocarbon-soluble content.

[Means for Solving the Problems] According to the present invention, the above object is (1) a repeating unit (a) derived from propylene, a repeating unit (b) derived from ethylene and a repeating unit (derived from 1-butene ( A propylene-based random copolymer comprising c), wherein (A) the propylene-derived repeating unit (a) is 96 to 86 mol%, and the ethylene-derived repeating unit (b) is
Is 0.5 to 6 mol% and the repeating unit (c) derived from 1-butene is in the range of 2.5 to 13 mol% and the c / (b + c) molar ratio is in the range of 0.3 to 0.9, (B) The intrinsic viscosity [η] measured at 135 ° C in decalin
Be in the range of 0.5 to 6 dl / g, (C) the melting point [Tm] measured by a differential scanning calorimeter
The temperature is in the range of 115 to 133 ° C., (D) the crystallinity measured by X-ray diffraction is 30 to
It is in the range of 60%, (E) the amount of soluble components in n-decane [W ₁ wt%] at 25 ° C is 0.03 (165-Tm) ≤ W ₁ ≤ 0.15 (165-Tm) [wherein Tm represents the above melting point], and (F) the 1-butene content B in the component soluble in n-decane
₁ (mol%) is 0.5B ₂ ≦ B ₁ ≦ 5.0B ₂ [wherein B ₂ is 1-in the propylene random copolymer;
The butene content (mol%) is within the range].

The present invention will be described in detail below.

In the propylene random copolymer of the present invention, the composition (A) of the copolymer has a propylene component (repeating unit (a) derived from propylene) of 96 to 86 mol%, preferably 95 to 88 mol%, More preferably 95 to 90
Mol%, 0.5 to 6 mol% of ethylene component (repeating unit (b) derived from ethylene), preferably 1 to 5 mol%, more preferably 1.5 to 4 mol% and 1
-Butene component (repeating unit (c) derived from 1-butene) is 2.5 to 13 mol%, preferably 3 to 11
It is in the range of mol%, more preferably 4 to 8 mol%.

When the propylene component in the copolymer is more than 96 mol%, the heat-sealing property at low temperature and the heat-sealability are deteriorated, and when the propylene component is less than 86 mol%, the blocking resistance is deteriorated or the rigidity of the film is deteriorated. descend. Further, the ethylene component in the copolymer is 6 mol%
When it is larger, the blocking resistance is deteriorated, and when the ethylene component is smaller than 0.5 mol%, the heat sealability and heat sealability at low temperature are deteriorated. Further, when the 1-butene component in the copolymer is more than 13 mol%, the blocking resistance is deteriorated, and the 1-butene component is 2.
When it is less than 5 mol%, the heat sealability and heat sealability at low temperature deteriorate.

The molar ratio c / (b + c) for the ethylene component (b) and the 1-butene component (c) is in the range of 0.3 to 0.9, preferably 0.4 to 0.8, more preferably 0.5 to 0.8. If the above molar ratio is larger than 0.9, the blocking resistance is deteriorated or the rigidity is deteriorated. The above molar ratio is 0.3
If it is smaller, the blocking resistance is deteriorated.

In the propylene random copolymer of the present invention, 135
The intrinsic viscosity [η] (B) measured in decalin at 0 ° C was 0.
It is in the range of 5 to 6, preferably 1 to 5. This characteristic value is a measure showing the molecular weight of the propylene random copolymer of the present invention, and by combining with other characteristic values, it is useful for providing the random copolymer having the above-mentioned excellent properties.

The melting point of the propylene random copolymer of the present invention measured by a differential scanning calorimeter [hereinafter, may be abbreviated as DSC melting point] (C) is 115 to 133 ° C., preferably 12
It is in the range of 0 to 130 ° C. The presence of the DSC melting point is a measure showing that the DSC melting point is a copolymer having crystallinity, which is distinguished from the conventional amorphous propylene random copolymer, and is combined with other characteristic values. This helps to provide a copolymer having the above-mentioned excellent properties. Where DS
C melting point is 2 after molding using Perkin Elmer DSC-II type
The pressed sheet having a thickness of 0.1 mm after 0 hours was measured at a temperature rising rate of 10 ° C / min from 25 to 200 ° C, and the maximum endothermic peak was taken as Tm.

The crystallinity (D) of the propylene random copolymer of the present invention measured by X-ray diffractometry is in the range of 30 to 60%, preferably 40 to 50%. This characteristic value is a scale indicating that the propylene random copolymer of the present invention is a crystalline random copolymer, and by combining with other characteristic values, the random copolymer having the excellent properties described above. Have been helpful in providing. Crystallinity is 180 ℃, 10 minutes then 2
It was determined by X-ray diffraction measurement of a 1.5 mm pressed sheet formed by pressing at 5 ° C. for 10 minutes.

In the propylene random copolymer of the present invention, 25 ° C
Soluble content in n-decane solvent [W ₁ wt%]
(E) is in the relationship with the melting point Tm of the copolymer, 0.03 (165-Tm) ≤ W ₁ ≤ 0.15 (165-Tm), preferably 0.04 (165-Tm) ≤ W ₁ ≤ 0.13 (165-Tm ) and particularly preferably 0.05 (165-Tm) ≦ W 1 ≦ 0.11 (165-Tm) ( where Tm shall apply numerically the melting point of the copolymer shows a value obtained by subtracting the Deimenshiyon) satisfies. This characteristic value shows the content of the rubber-like polymer component having a high monomer content and / or the low molecular weight polymer component in the propylene random copolymer of the present invention, and the composition distribution and the molecular weight distribution of the copolymer are broad and narrow. The propylene-based random copolymer conventionally known has a large amount of the n-decane-soluble component in the above-mentioned melting point range, has poor surface non-adhesiveness, and causes a large blocking property. There is. This characteristic value in the propylene-based random copolymer of the present invention is combined with other characteristic values to help provide the above-mentioned copolymer having excellent properties. In the present invention, the soluble component of the copolymer in the n-decane solvent at 25 ° C. is collected by the following method. That is, in a flask equipped with a stirring blade, 5 g of the copolymer sample, 0.3 g of 2,
6-ditert-butyl-4-methylphenol, 500 ml of n
-Add decane and dissolve on a 140 ° C oil bath. After the solution is dissolved, it is naturally cooled at room temperature for about 3 hours and then cooled on a water bath at 25 ° C for 12 hours. N- containing precipitated copolymer and dissolved polymer
Overseparate the decane solution with a G-4 glass filter,
The solution is dried at 10 mmHg at 150 ° C until a constant weight is obtained,
-Collect the polymer that dissolves in decane. The weight was measured, and the soluble amount of the copolymer in the n-decane solvent at 25 ° C. was calculated and determined as a percentage with respect to the weight of the sample copolymer.

The content (B ₁ mol%) (F) of 1-butene in the n-decane-soluble component of the propylene random copolymer of the present invention is
The following formula 0.5B ₂ ≤B ₁ ≤5.0B ₂ preferably 0.6B ₂ ≤B ₁ ≤3.0B ₂ particularly preferably 0.7B ₂ ≤B ₁ ≤1.5B _{2 more} preferably 0.9B ₂ ≤B ₁ ≤1.1B ₂ [In the formula, B ₂ is the content rate (mol%) of 1-butene of the random copolymer]. If the content ratio of 1-butene in the n-decane-soluble component of the copolymer is B ₁ > 5.0B ₂ , the blocking resistance is deteriorated.

The propylene random copolymer of the present invention satisfies the binding factors represented by the characteristic values of (A) to (F) described above.

The propylene-based random copolymer of the present invention has a low content of a low molecular weight rubbery polymer component as compared with conventionally known propylene-based random copolymers, and has heat sealability, heat seal impartability, and transparency. It is characterized by excellent blocking resistance, low hydrocarbon-soluble content, and narrow composition distribution.

As described above, the propylene random copolymer of the present invention is excellent in heat-sealing property, heat-sealing property, transparency, and blocking resistance, and thus is particularly useful as a heat-sealing composition and a heat-sealing laminate.

The propylene random copolymer of the present invention contains, for example, (A) magnesium, titanium, halogen and an electron donor as essential components and has an average particle size of about 5 to about.
Highly active and highly stereoregular titanium catalyst component having a geometric standard deviation value of less than 2.1 at 300 μm, (B) an organometallic compound catalyst component of Group 1 to 3 metal of the Periodic Table, and (C) an electron In the presence of a catalyst formed from a donor catalyst component, said catalyst component (A) containing an electron donor (C) in the range of 0.5 to 5 moles per gram atom of titanium. In the presence of an α-olefin prepolymer catalyst obtained by prepolymerizing an α-olefin having 2 to 20 carbon atoms in the range of 20 to 1000 g per gram of titanium catalyst component (A), propylene, ethylene and 1 -Butene can be obtained by copolymerizing at a polymerization temperature of 50 to 130 ° C under the conditions that they form a gas phase.
As will be described in detail below, the catalyst component, the copolymerization conditions, and the other copolymer production conditions can be easily and experimentally selected and set by using the above-mentioned characteristics (A) to (F) as a guide for the copolymer of the present invention. be able to. In the present invention, since the presence of the propylene-based random copolymer of the present invention having the characteristic value of the conventional literature undescribed and the presence of the copolymer and the excellent properties of the copolymer were clarified, The production conditions of the propylene random copolymer of the present invention can be experimentally easily and appropriately selected and set.

The highly active, highly stereoregular solid titanium catalyst component (A) used in the present invention contains magnesium, titanium, halogen and an electron donor as essential components, and the magnesium / titanium (atomic ratio) is 1 or more. Large and preferably 2
To 50, particularly preferably 6 to 30, halogen / titanium (atomic ratio) is preferably 4 to 100, particularly preferably 6 to 40, electron donor / titanium (molar ratio) is preferably 0.1 to 10, particularly preferably. It is in the range of 0.2 to 6. Its specific surface area is preferably 3 m ² / g or more,
More preferably 40 m ² / g or more, more preferably 100 m ² / g
Or 800 m ² / g. Usually, titanium compounds are not eliminated by simple means such as hexane washing at room temperature.
Further, in addition to the above essential components, other elements, metals, functional groups, etc. may be contained. In addition, Teflon, polyethylene,
It may be supported on an organic or inorganic carrier such as polypropylene, silica, or alumina.

The solid titanium catalyst component (A) has an average particle size of 5 to 300.
μ, preferably 10 to 150 μ, particularly preferably 15 to 100 μ and the geometric standard deviation of the particle size distribution is less than 2.1,
It is preferably 1.9 or less, more preferably 1.7 or less.

Here, the particle size distribution of the titanium catalyst component particles can be measured by a light transmission method. Specifically, dilute the catalyst component in an inert solvent such as decalin to a concentration of about 0.01 to 0.5%, put it in a measurement cell, shine light on the cell, and pass the liquid in a sedimented state with particles. The particle size distribution is measured by continuously measuring the light intensity. The standard deviation σg is obtained from the lognormal distribution function based on this particle size distribution. More specifically, σg is obtained as the ratio (D ₅₀ / D ₁₆ ) of the average particle diameter (D ₅₀ ) and the particle diameter (D ₁₆ ) that is 16 wt% in view of the small particle diameter. The average particle diameter of the catalyst is shown by the weight average diameter.

The solid titanium catalyst component (A) has the ability to produce a highly stereoregular polymer with high catalytic efficiency. For example, when homopolymerization of propylene is carried out under the same conditions, the isotacticity (boiling point) n-heptane-insoluble matter) 92% or more, particularly 96% or more of polypropylene is 3,000 g or more, particularly 5,000 g or more, and more preferably 10,000 per 1 mmol of Ti.
It has the ability to manufacture over g. And preferably,
It has a shape such as a true sphere, an ellipsoid, or a granule.

By using a titanium catalyst component satisfying these requirements, a copolymer having a high ethylene content can be produced with good operability and in a high yield.

The titanium catalyst component (A) satisfying all the above conditions is prepared by forming a magnesium compound having an average particle size and particle size distribution, more preferably a shape in the above range, and then preparing the catalyst. It can be obtained by a method of performing, or a method of bringing a liquid magnesium compound and a liquid titanium compound into contact with each other to form a solid catalyst having the above-mentioned particle properties.

In addition to the above-mentioned carriers, Mg compound, Ti
Examples thereof include a method of supporting a compound and an electron donor, or granulating the fine powdery catalyst into the above-described preferable shape.
Such methods are described in, for example, JP-A-55-135102 and JP-A-55-135103.
No. 56-811, No. 56-67311, Japanese Patent Application No. 56-181019,
No. 61-21109 is disclosed.

A few examples of these methods are briefly described.

(1) Reaction of a magnesium compound / electron donor complex having an average particle size of 5 to 300μ and a geometric standard deviation σg of particle size distribution of less than 2.1 with an electron donor and / or an organoaluminum compound or a halogen-containing silicon compound. It is either pretreated with an auxiliary agent or, without pretreatment, is reacted with a titanium halide compound which forms a liquid phase under the reaction conditions, preferably titanium tetrachloride.

(2) A solid having an average particle diameter of 5 to 300 μ and a geometric standard deviation σg of less than 2.1 obtained by reacting a liquid material of a magnesium compound having no reducing ability with a liquid titanium compound in the presence of an electron donor. Precipitate the ingredients. If necessary, a liquid titanium compound, preferably titanium tetrachloride, or it is reacted with an electron donor.

Particularly, in the present invention, in the case of using the magnesium compound or the electron donor complex precipitated from the liquid material as a liquid solid in the method (1), or (2)
Good results are obtained when the precipitation of the solid component by the method described in (1) is carried out under the condition that a spherical solid is precipitated.

As the magnesium compound used for the preparation of the titanium catalyst component, magnesium oxide, magnesium hydroxide, hydrotalcite, magnesium carboxylate, alkoxy magnesium, allyloxy magnesium, alkoxy magnesium halide, allyloxy magnesium halide, magnesium dihalide, Examples thereof include organomagnesium compounds, reaction products of organomagnesium compounds with electron donors, halosilanes, alkoxysilanes, silanols, aluminum compounds and the like. The organoaluminum compound that may be used in the preparation of the titanium catalyst component may be selected from the organoaluminum compounds that can be used in the olefin polymerization described below. Furthermore, examples of the halogen-containing silicon compound that may be used for preparing the titanium catalyst component include tetrahalogenated silicon, alkoxyhalogenated silicon, alkylhalogenated silicon, and halopolysiloxane.

Examples of titanium compounds used for preparing the titanium catalyst component include titanium halides, alkoxy titanium halides,
Examples thereof include allyloxytitanium halides, alkoxytitaniums, and allyloxytitanium, and titanium tetrahalide, particularly titanium tetrachloride, is preferable.

Examples of electron donors that can be used to prepare the titanium catalyst component include alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, and alkoxysilanes of acid anhydrides. Oxygen electron donors, nitrogen-containing electron donors such as ammonia, amines, nitriles, and isocyanates can be used.

More specifically, it has 1 to 18 carbon atoms such as methanol, ethanol, propanol, pentanol, hexanol, octanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol and isopropylbenzyl alcohol.
Alcohols of 6 to 20 carbon atoms which may have a lower alkyl group such as phenol, cresol, xylenol, ethylphenol, propylphenol, nonylphenol, cumylphenol and naphthol; acetone, methylethylketone, methylisobutylketone C3 to C15 ketones such as acetophenone and benzophenone; acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde,
Aldehydes having 2 to 15 carbon atoms such as tolualdehyde and naphthaldehyde; methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate, chloroacetic acid. Methyl, ethyl dichloroacetate,
Methyl methacrylate, ethyl crotonate, cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, methyl toluate, toluyl Ethyl acid, amyl toluate, ethyl ethyl benzoate, methyl anisate, ethyl anisate, ethyl ethoxybenzoate,
Dibutyl malonate, isopropyl diethyl malonate, n
-Diethyl butylmalonate, diethyl phenylmalonate, diethyl 2-allylmalonate, diethyl diiso-butylmalonate, diethyl di-n-pentylmalonate, di-n-butyl succinate, diethyl methylsuccinate, dibutyl ethylsuccinate, dimethyl maleate, dibutyl maleate. , Monooctyl maleate, dioctyl maleate, dibutyl butyl maleate, diethyl butyl maleate, diisooctyl fumarate, diethyl itaconate, di-n-butyl itaconate, dimethyl citracone, diethyl 1,2-cyclohexanedicarboxylate, 1 2,2-Cyclohexanedicarboxylate di2-ethylhexyl, dimethyl phthalate, mono isobutyl phthalate, diethyl phthalate, ethyl n-butyl phthalate, di-n-butyl phthalate, n-butyl phthalate, isobutyl phthalate, lid Di n-heptyl phthalate, di 2-ethylhexyl phthalate, di n- octyl,
Dyneopentyl phthalate, benzyl butyl phthalate, diphenyl phthalate, diiso-butyl naphthalenedicarboxylate, di2-ethylhexyl sebacate, γ-butyrolactone, δ-valerotactone, coumarin, phthalide, and ethylene carbonate having 2 to 30 carbon atoms. Organic acid esters; C2 to C15 such as acetyl chloride, benzoyl chloride, toluic acid chloride, anisic acid chloride
C2 to C20 ethers such as methyl ether, ethyl ether, isopropyl ether, butyl ether, isoamyl ether, tetrahydrofuran, anisole and diphenyl ether; acids such as acetic acid amide, benzoic acid amide and toluic acid amide Amides; methylamine, ethylamine, diethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, tetramethylmethylenediamine, tetramethylethylenediamine, and other amines; acetonitrile, benzonitrile, tolunitrile, and other nitrites; Organophosphorus compounds having POC bonds such as trimethyl phosphate and triethyl phosphite; alkoxysilanes such as ethyl silicate and diphenyldimethoxysilane; Door can be. Two or more kinds of these electron donors can be used.

The electron donors that are preferably contained in the titanium catalyst component (A) include organic acid or inorganic acid esters, alkoxy (aryloxy) silane compounds, ethers, ketones, tertiary amines, acid halides, acid anhydrides. Organic acid esters and alkoxy (aryloxy) silane compounds are particularly preferable because they do not have active hydrogen, and among these, esters of aromatic monocarboxylic acids and alcohols having 1 to 8 carbon atoms, malonic acid, substituted malonic acid, substituted amber. Esters of dicarboxylic acids such as acid, maleic acid, substituted maleic acid, 1,2-cyclohexanedicarboxylic acid and phthalic acid with alcohols having 2 or more carbon atoms are particularly preferable. Of course, these electron donors do not necessarily have to be used as raw materials when preparing the titanium catalyst, but may be used as other compounds that can be converted into these electron donors and converted into these electron donors during the catalyst preparation process.

After completion of the reaction, the titanium catalyst component obtained by the various methods as exemplified above can be purified by thoroughly washing with a liquid inert hydrocarbon. As the inert liquid hydrocarbon used for this purpose, n-pentane, isopentane, n-pentane,
Hexane, isohexane, n-heptane, n-octane, isooctane, n-decane, n-dodecane, kerosene,
Aliphatic hydrocarbons such as liquid paraffin; Alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane; Aromatic hydrocarbons such as benzene, toluene, xylene, cymene; Chlorobenzene, dichloroethane Such halogenated hydrocarbons or mixtures thereof can be exemplified.

The preferred organometallic compound catalyst component (B) used in the present invention is an organoaluminum compound, and a compound having at least one Al-carbon bond in the molecule can be used. For example, (i) the general formula R ¹ _m Al (OR ² ) nHpXq ▼ (wherein R ¹ and R ² are hydrocarbon groups usually containing 1 to 15, preferably 1 to 4 carbon atoms and may be the same or different from each other. Halogen, m is 0 <m ≦ 3, n is 0 ≦ n
<3, p is a number 0 ≦ p <3, q is a number 0 ≦ q <3, and
Moreover, m + n + p + q = 3), an organoaluminum compound represented by the formula (ii) the general formula ▲ M ¹ AlR ¹ ₄ ▼ (where M is
¹ is Li, Na or K, and R ¹ is the same as the above), and a complex alkylated product of a Group 1 metal and aluminum.

Examples of the organoaluminum compound belonging to (i) above include the following. General formula ▲ R ¹ _m Al (OR ² ) _3-m ▼
(Wherein R ¹ and R ² are the same as above. M is preferably 1.5
≦ m <3). General formula ▲ R ¹ _m AlX _3-m ▼ (where R
¹ is the same as above. X is halogen, m is preferably 0 <m
<3), the general formula ▲ R ¹ _m AlH _3-m ▼ (where R ¹ is the same as above, m is preferably 2 ≦ m <3), the general formula ▲
R ¹ _m Al (OR ² ) nXq ▼ (where R ¹ and R ² are the same as before. X is halogen, 0 <m ≦ 3, 0 ≦ n <3, 0 ≦ q <3, and m
+ N + q = 3) and the like.

In the aluminum compound belonging to (i), more specifically, trialkyl aluminum such as triethyl aluminum and tributyl aluminum, trialkenyl aluminum such as triisoprenyl aluminum, diethyl aluminum ethoxide, dialkyl aluminum alkoxide such as dibutyl aluminum butoxide, In addition to alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide, partially alkoxylated alkylaluminum having an average composition represented by ▲ R ¹ _2.5 Al (OR ² ) _0.5 ▼, diethyl Aluminum chloride, dibutyl aluminum chloride, dialkyl aluminum halides such as diethyl aluminum bromide, ethyl aluminum Alkylaluminum sesquihalides such as umsesquichloride, butylaluminum sesquichloride, ethylaluminum sesquibromide,
Partially halogenated alkyl aluminum such as ethyl aluminum dichloride, propyl aluminum dichloride, butyl aluminum dibromide and the like alkyl aluminum dihalide, diethyl aluminum hydride, dialkyl aluminum hydride such as dibutyl aluminum hydride, ethyl aluminum dihydride, Partially hydrogenated alkylaluminums such as alkylaluminum dihydrides such as propylaluminium dihydride, partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxy chloride, butylaluminum butoxycyclolide, ethylaluminum ethoxybromide. Is. Further, the compound similar to (i) may be an organoaluminum compound in which two or more aluminums are bound via an oxygen atom or a nitrogen atom. Examples of such compounds include (C ₂ H ₅ ) ₂ AlOAl (C ₂ H ₅ ) ₂ , (C ₄ H ₉ ) AlOAl (C ₄ H ₉ ) ₂ , Can be exemplified.

The compounds belonging to (ii) above include LiAl (C ₂ H ₅ ) ₄ and LiAl
(C ₇ H _{15) 4} etc. can be exemplified. Among these, it is particularly preferable to use trialkylaluminum or a mixture of trialkylaluminum and alkylaluminum halide or aluminum halide.

Examples of the electron donor used as the catalyst component (C) are amines, amides, ethers, ketones, nitriles, phosphines, stibines, arsines, phosphoramides, esters, thioethers, thioesters. And acid anhydrides, acid halides, aldehydes, alcoholates, alkoxy (aryloxy) silanes, organic acids, and amides and salts of metals belonging to Groups 1 to 4 of the periodic table. . Salts can also be formed in situ by the reaction of an organic acid with an organometallic compound used as catalyst component (B).

Specific examples thereof include titanium catalyst component (A)
The electron donor contained in the above can be selected from those exemplified above. Good results are obtained with organic acid esters, alkoxy (aryloxy) silane compounds, ethers, ketones, acid anhydrides, amines and the like. Particularly when the electron donor in the titanium catalyst component (A) is a monocarboxylic acid ester, the electron donor as the component (C) is preferably an alkyl ester of an aromatic carboxylic acid.

When the electron donor in the titanium catalyst component (A) is an ester of a dicarboxylic acid exemplified above as a preferable one and an alcohol having 2 or more carbon atoms, the general formula R _n Si (O
R ¹ ) _4-n (wherein R and R ¹ are hydrocarbon groups, and an alkoxy (aryloxy) silane compound represented by 0 ≦ n <4) or an amine having large steric hindrance is preferably used as the component (C). . Specific examples of the alkoxy (aryloxy) silane compound include trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethylditoexisilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t. -Amylmethyldiethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, bis-o-tolyldimethoxysilane, bis-m-tolyldimethoxysilane, bis-p-tolyldimethoxysilane, bis-p-
Tolyldiethoxysilane, p-tolylmethyldimethoxysilane, bisethylphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyl Trimethoxysilane, n-propyltriethoxysilane, decylsilmethoxysilane, decyltriethoxysilane, phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, n-butyltriethoxysilane, isobutyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyl Triethoxysilane, chlorotriethoxysilane, ethyltriisopropoxysilane,
Vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2-norbornanetrimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, ethyl silicate, butyl silicate, trimethylphenoxysilane, Methyltriallyloxy silane, vinyl tris (β-methoxyethoxysilane, vinyltriacetoxysilane, dimethyltetraethoxydisiloxane, etc., among which ethyltriethoxysilane, n-propyltriethoxysilane, t-butyltriethoxysilane, Vinyltriethoxysilane, phenyltriethoxysilane, vinyltributoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, bis-p-tolyldimethyl Preferred are toxysilane, p-tolylmethyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, diphenyldiethoxysilane, and ethyl silicate. Also, the steric hindrance is large. As the amine, 2,2,6,6-
Tetramethylpiperidine, 2,2,5,5-tetramethylpyrrolidine, derivatives thereof, tetramethylmethylenediamine and the like are particularly preferable.

Among these compounds, an alkoxy (aryloxy) silane compound is particularly preferable as the electron donor used as the catalyst component (C).

In obtaining the propylene random copolymer of the present invention, for example, 20 to 1000 g per 1 g of the titanium catalyst component,
Preferably 30 to 500 g, more preferably 40 to 200 g
After the prepolymerization of (1), random copolymerization of propylene, ethylene and α-olefin having 4 to 10 carbon atoms is carried out by a so-called gas phase polymerization method in which a hydrocarbon solvent is substantially absent. preferable.

For the prepolymerization, it is preferable to use a catalyst system in which the above-mentioned titanium catalyst component (A) and the above-mentioned organometallic catalyst component (B) as well as the above-mentioned electron donor catalyst component (C) coexist. 0.1 per gram atom of titanium in the titanium catalyst component (A).
It is preferred to use an electron donor (C) in the range of 1 to 30 mol, preferably 0.5 to 10 mol, more preferably 1 to 5 mol. Further, the prepolymerization is carried out by polymerizing α-olefin having 2 to 20 carbon atoms in an inert hydrocarbon solvent or without using a solvent or in a liquid monomer. It is particularly preferred to carry out in an inert hydrocarbon solvent.

As the inert hydrocarbon solvent used in the prepolymerization, propane, butane, n-pentane, iso-pentane, n-
Hexane, isohexane, n-heptane, n-octane, isooctane, n-decane, n-dodecane, aliphatic hydrocarbons such as kerosene, cyclopentane, methylcyclopentane, cyclohexane, alicyclic hydrocarbons such as methylcyclohexane, Examples thereof include aromatic hydrocarbons such as benzene, toluene and xylene, and halogenated hydrocarbons such as methylene chloride, ethyl chloride, ethylene chloride and chlorobenzene. Among them, aliphatic hydrocarbons, especially those having 4 to 4 carbon atoms can be mentioned. Ten aliphatic hydrocarbons are preferred.

When an inert solvent or a liquid monomer is used in the prepolymerization, the titanium catalyst component (A) is converted to titanium atom in an amount of 0.001 to 500 mmol, especially 0.00
The amount is preferably 5 to 200 mmol, and the organoaluminum compound (B) has an Al / Ti (atomic ratio) of 0.5 to 20.
It is preferably used in a ratio of 0, preferably 1.0 to 50, more preferably 2.0 to 20.

Examples of α-olefins used for prepolymerization include ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1- Decene, 1-dodecene, 1
Those having 10 or less carbon atoms such as tetradecene and 1-octadecene are preferable, those having 3 to 6 carbon atoms are more preferable, and propylene is particularly preferable. These α-olefins may be homopolymerized, or may be copolymerized with two or more kinds as long as a crystalline polymer is produced.

The polymerization temperature in the prepolymerization varies depending on the kinds of the α-olefin and the inert hydrocarbon solvent used and cannot be specified unconditionally, but it is generally about -40 to 80 ° C. For example, when α-olefin is propylene, -40 or
70 ° C., -40 to 40 ° C. in the case of 1-butene, and -40 to 70 ° C. in the case of 4-methyl-1-pentene and 3-methyl-1-pentene. Hydrogen can coexist in the preliminary polymerization.

In the production of the propylene-based random copolymer of the present invention, random copolymerization of propylene, ethylene and 1-butene is carried out using the catalyst obtained by prepolymerizing α-olefin. 1,000 to 100,000 g per gram of the titanium catalyst component (A) of the above catalyst obtained by prepolymerizing α-olefin.
Preferably 2,000 to 50,000 g, more preferably 3,000
To 30,000 g of a gas phase mixture of propylene, ethylene and 1-butene are copolymerized. To obtain the copolymer of the present invention, it is necessary to copolymerize the monomers in the gas phase. Further, it is preferable to gasify a part or all of these 1-butenes outside the polymerization system and then supply the 1-butene to the polymerization system. Particularly, it is preferable to completely gasify the 1-butene and then supply the polymerization system.

The polymerization temperature is 50 to 130 ° C, preferably 65 to 120 ° C,
More preferably, it is carried out at 80 to 110 ° C. The polymerization pressure is not particularly limited as long as the monomer is in the gas phase at the use temperature, but 1
To 50 kg / cm ² , preferably 2 to 30 kg / cm ² , and more preferably 5 to 20 kg / cm ² . Further, an inert gas such as methane, ethane, propane and nitrogen which forms a gas phase state in the polymerization system may be appropriately supplied.

[Measurement of film blocking resistance and complete heat-sealing temperature] A method for determining the film blocking resistance and complete heat-sealing temperature of the obtained copolymer is described below.

Film making 0.1mm thick aluminum sheet, polyester sheet (made by Toray Industries, Inc., trade name Lumirror) and 50μ Kapton (made of polyimide resin) with the center cut into 15cm × cm squares Are laid in this order, and 0.8 g of sample is placed in this center (cutout part). Next, a lumirror, an aluminum plate, and a press plate are further stacked in this order (Fig.
1).

Put the sample sandwiched between the above press plates in a 200 ° C hot press and preheat for about 5 minutes, then pressurize (20 kg / cm ² G) depressurization operation to remove air bubbles in the sample. 3
Repeat times. Then, finally pressurize to 150kg / cm ² G, 5
Heat under pressure for minutes. After depressurizing, remove the press plate from the press machine and transfer it to another press machine where the crimping area was maintained at 30 ° C.
After pressure cooling at 0 kg / cm ² for 4 minutes, the pressure is released and the sample is taken out. Uniform 50-70 μm of the obtained film
The following film is used as the measuring film.

Blocking resistance test Two films cut out to a size of 6 x 10 cm are stacked, sandwiched between two sheets of uniform thickness, and then a glass plate of about 5 mm thickness is further sandwiched between them and placed in a constant temperature bath at 60 ° C under a load of 7 kg. Leave for 2 days (aging). After taking the film out of the constant temperature bath and cooling it to room temperature, part of one end of this double-layered film was peeled off, a Teflon rod was inserted here, the end of the peeled film was clipped, and a tensile test was conducted. Secure it to the upper chuck of the machine. At the same time, the Teflon rod is fixed to the lower chuck via the fixing bracket (see Fig. 2). The stress when two films are separated from each other is measured using a tensile tester through a Teflon rod fixed by pulling up the upper chuck at a speed of 10 cm / min. The obtained stress value is divided by the width of the film used (6 cm) to obtain the film blocking value (g / cm), which is a measure of the blocking resistance.

Measurement of heat seal strength The film prepared by the above-mentioned method is placed in a thermostatic chamber at 50 ° C.
Leave for days (aging). Before aging, attach paper to both sides of the film so that the films do not touch each other. Cut the above-aged film into 15mm-width strips, stack the two pieces, and then
Heat seal with a Teflon film with a thickness of 0.1 mm sandwiched between them. Heat sealing is performed by keeping the lower temperature of the heat plate of the heat sealer constant at 70 ° C and changing only the temperature of the upper part of the heat plate in steps of 5 ° C. Pressure during heat sealing is 2k
The sealing width is 5 mm (hence the sealing area is 15 mm x 5 mm), with g / cm ² and heat sealing time of 1 second.

The heat-sealing strength is obtained by performing a peeling test on the peeling strength of the film heat-sealed at each of the above heat-sealing temperatures at a pulling speed of 30 cm / min (Fig. 3).
reference).

The peel strength at each heat-sealing temperature in steps of 5 ° C. is obtained by the method described above, and a plot of the heat-sealing temperature vs. the peel strength is connected by a curve. Based on this curve, the heat seal temperature at which the peel strength is 800 g / 15 cm is defined as the complete heat seal temperature (see Fig. 4).

Example 1 [Preparation of highly active, highly stereoregular titanium catalyst component] 714 g of anhydrous magnesium chloride, 3.5 l of decane and 2-ethylhexyl alcohol were heated to react at 130 ° C. for 2 hours to form a uniform solution, and then this solution was prepared. Phthalic anhydride is added therein, and the mixture is further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride in the homogeneous solution. The homogeneous solution thus obtained is cooled to room temperature and then added dropwise to 20 liters of titanium tetrachloride kept at -20 ° C over 1 hour. After the completion of charging, the temperature of this mixed solution was raised to 110 ° C over 4 hours, and when it reached 110 ° C, diisobutylphthalate 0.4 was added.
l is added and the mixture is kept at the same temperature for 2 hours with stirring.
After the completion of the reaction for 2 hours, a solid portion was collected by heating, and the solid portion was resuspended in 28 l of TiCl ₄ and then again at 110 ° C.
The heating reaction is performed for a time. After completion of the reaction, the solid portion is again collected by heating, and washed with decane and hexane at 110 ° C. sufficiently until no free titanium compound is detected in the solution. The titanium catalyst component synthesized by the above manufacturing method was dried with a dryer. The titanium catalyst component thus obtained had a composition of 2.3% by weight of titanium, 58.0% by weight of chlorine, 18.0% by weight of magnesium and 14.0% of diisobutylphthalate.
% By weight.

The titanium catalyst component was a granular catalyst having an average particle size of 18μ and a geometric standard deviation (σg) of particle size distribution of 1.2.

[Preliminary Polymerization] 10 mmol of hexane was mixed with 100 mmol of triethylaluminum and 20 mmol of diphenyldimethoxysilane.
A titanium catalyst (dry product) synthesized by the above-mentioned synthesis method was added to the mixed solution (10 mmol in terms of titanium atom),
It was reslurried for 2 hours. Next, propylene was supplied, and 3 Hr prepolymerization was performed so that 50 g per 1 g of the titanium catalyst component. The polymerization temperature was controlled at 0-8 ° C. After the completion of prepolymerization,
Wash 6 times with hexane, then dilute with hexane so that the concentration of titanium catalyst component becomes 2 mMol / l as Ti atom,
Stored in a container with stirrer.

[Polymerization] A polymerization reaction was carried out using a fluidized bed type polymerization reactor having a diameter of 340 mm and a reaction volume of 40 l. In the fluidized bed type polymerization reactor, the catalyst was continuously sprayed from a catalyst supply nozzle as a mixture consisting of 0.6 mmol Ti / Hr, N ₂ gas 100 Nl / Hr, and propane (liquid) 2.5 l / H. A continuous gas phase polymerization reaction was carried out while continuously supplying a mixed olefin composed of ethylene, propylene and 1-butene as a raw material olefin and H ₂ gas as a molecular weight control agent. Of the raw material olefin, 1-butene was vaporized by a vaporizer. The composition of the raw material gas at the time of supply was as follows, and the supply rate of propylene was 5160 Nl / H.

C ₄ ⁼ / C ₃ ⁼ (mol) 0.0977 C ₂ ⁼ / C ₃ ⁼ (〃) 0.0233 H ₂ / C ₃ ⁼ (〃) 0.0016 N ₂ / C ₃ ⁼ (〃) 0.0388 During gas phase polymerization reaction Temperature is 90 ℃, pressure is 8.0kg / cm ² G,
The gas superficial velocity is 40 cm / S, and the obtained ethylene,
Propylene, 1-butene random copolymer production of 5k
The supply amount of the prepolymerized catalyst was controlled so as to be g / H.
Triethylaluminum was previously mixed with hexane to 200 mMol / l
To a concentration of 15-20 mmol / H, which was continuously fed. On the other hand, diphenyldimethoxysilane was prepared in advance with hexane to a concentration of 200 mMol / l and the concentration of diphenyldimethoxysilane was 15-20 mmol / H.
It was continuously supplied at r. Table 1 shows other polymerization conditions and the results of the basic physical properties and film physical properties of the polymer obtained by the above polymerization.

Examples 2 to 4 Preliminary polymerization was carried out in the same manner as in Example 1 using the titanium catalyst component prepared in the same manner as in Example 1. Then, random copolymerization was carried out by the gas phase polymerization method under the conditions shown in Table 1. Table 1 shows the basic physical properties and film physical properties of the produced copolymer. Incidentally, only in Example 4, the prepolymerization condition was set such that the amount of propylene supplied was 96 g per 1 g of the titanium catalyst component.
Also, the prepolymerization time was changed to 5 Hr.

Comparative Example 1 The prepolymerization amount was changed to 3 g per 1 g of the catalyst, and the copolymerization conditions were changed to those shown in Table 3. Table 2 shows the basic physical properties and film physical properties of the obtained copolymer.

EFFECTS OF THE INVENTION The present invention provides a propylene-based random copolymer of propylene, ethylene and 1-butene, which has excellent heat-sealing properties, heat-sealing properties, transparency, and blocking properties and has a low hydrocarbon-soluble content. .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic cross-sectional view of the film preparation method used in the test, FIG. 2 shows a schematic view of the method for measuring the blocking value of the film, and FIG. 3 shows the heat-sealing strength. FIG. 4 shows a schematic diagram of the measuring method, and FIG. 4 shows a relationship diagram between the heat sealing temperature and the peel strength.

 ─────────────────────────────────────────────────── --Continued from the front page (56) Reference JP-A-59-47210 (JP, A) JP-A-54-26891 (JP, A) JP-A-63-95208 (JP, A) JP-A-56- 120716 (JP, A) JP 60-258216 (JP, A) JP 55-145713 (JP, A) JP 55-115415 (JP, A) JP 55-115416 (JP, A) Japanese Patent Publication Sho 55-6643 (JP, B2)

Claims (1)

[Claims] 1. A propylene random copolymer comprising a repeating unit (a) derived from propylene, a repeating unit (b) derived from ethylene and a repeating unit (c) derived from 1-butene, wherein: ) 96 to 86 mol% of the repeating unit (a) derived from propylene, and the repeating unit (b) derived from ethylene
Is 0.5 to 6 mol% and the repeating unit (c) derived from 1-butene is in the range of 2.5 to 13 mol% and the c / (b + c) molar ratio is in the range of 0.3 to 0.9, (B) The intrinsic viscosity [η] measured at 135 ° C in decalin
Be in the range of 0.5 to 6 dl / g, (C) the melting point [Tm] measured by a differential scanning calorimeter
The temperature is in the range of 115 to 133 ° C., and (D) the crystallinity measured by X-ray diffraction is 30 to
It is in the range of 60%, (E) the amount of soluble components in n-decane [W ₁ wt%] at 25 ° C is 0.03 (165-Tm) ≤ W ₁ ≤ 0.15 (165-Tm) [wherein Tm represents the above melting point], and (F) the content of 1-butene in the component soluble in n-decane B ₁
(Mol%) is 0.5B ₂ ≦ B ₁ ≦ 5.0B ₂ [wherein B ₂ is 1-in the propylene-based random copolymer.
The content of butene is (mol%)].