JPH07228630A - Highly crystalline polypropylene composition and its production - Google Patents

Abstract

PURPOSE:To obtain the subject composition capable of raising its molding rate, excellent in rigidity, tensile strength, transparency and surface characteristics, useful for structural materials, films etc., by incorporating a crystalline polypropylene with a specified amount of a specific nucleating agent polymer. CONSTITUTION:This highly crystalline polypropylene composition is obtained by incorporating (A) a crystalline polypropylene with (B) 10-10000wt.ppm of a nucleating agent polymer such as a polymer produced by polymerizing, in the presence of a metallocene-based polymerization catalytic system, at least one kind of monomer selected from >=4C branched alpha-olefins such as 3- methyl-1-butene, vinyl group-contg. cyclic hydrocarbon compounds such as vinylcyclohexane, alkenylsilanes such as vinyl trimethylsilane, indene compounds, and vinyl group-substituted aromatic compounds such as vinylnorbornene and styrene. It is preferable that the ratio Mw/Mr of the nucleating agent polymer be <=3 (where, Mw and Mr denote weight-average molecular weight and number- average molecular weight, respectively).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a highly crystalline polypropylene composition having excellent mechanical properties such as rigidity and tensile strength, transparency and surface characteristics and capable of increasing the molding rate, and a method for producing the same. .

[0002]

2. Description of the Related Art In order to use polypropylene as a structural material for automobiles and home electric appliances, rigidity,
It is required to have excellent heat resistance and various good mechanical properties. For that purpose, stereoregularity, crystallinity,
It is necessary to produce a propylene polymer having a higher melting point and the like, and further, it is required to have high fluidity, a high crystallization temperature, and a high crystallization rate in order to improve the productivity of molding processing.

Heretofore, as a catalyst system for producing a highly crystalline polypropylene, a combination of titanium trichloride and a dialkylaluminum chloride and a combination of an electron donor, a titanium compound and an electron on a magnesium chloride carrier have been used. A combination of a solid catalyst component carrying a donor, an organoaluminum compound such as trialkylaluminum, and an electron donor as a third component is known.

In recent years, many combinations of metallocene complexes such as titanium, zirconium and hafnium and ionic compounds consisting of alkylaluminum oxy compounds such as methylalumoxane or tetrakis (pentafluorophenyl) borate anions have been proposed, It is known that a polypropylene having a narrow molecular weight distribution and stereoregularity distribution and excellent physical properties can be obtained.

On the other hand, in order to further increase the crystallization temperature and crystallization rate of polypropylene produced using the above titanium trichloride-based and magnesium chloride-supporting titanium-based catalysts,
Usually, a polypropylene composition is prepared by mixing an inorganic nucleating agent such as talc, a metal salt such as aluminum carboxylate (JP-A-3-220208), an organic nucleating agent such as a sorbitol derivative and an organic phosphate. To manufacture.

As a method for mixing the nucleating agent with polypropylene, a Banbury mixer, a blender or the like is generally used. However, these methods cause problems such as variations in the physical properties of the product due to poor dispersion of the nucleating agent, an increase in the density of the polypropylene composition after addition, contamination of the molding machine, and coloring of the polymer. Therefore, for example, Japanese Patent Laid-Open No. 3-2202
As a method for improving dispersibility, Japanese Patent Publication No. 08 discloses a method of adding a nucleating agent to a polymerization system in advance when polymerizing propylene. However, although the dispersibility is improved, the problems of staining and coloring still remain.

In order to solve this problem, in recent years, many proposals have been made regarding high melting point nucleating agent polymers. Further, as a method for enhancing the nucleating effect by highly dispersing this nucleating agent polymer in polypropylene, for example, JP-A-60-1
39710, 61-151204, 62-1738, JP1-156305, 2-169605, 2-20
No. 6605, No. 2-272045, No. 4-202505, etc., olefins, diolefins, etc. that produce crystalline polymers at high melting points other than propylene by titanium trichloride-based or magnesium chloride-supported titanium-based catalysts. It has been proposed to preliminarily polymerize the above, and further main-polymerize propylene to mix a fine crystalline polymer having a high melting point other than propylene in the polypropylene.

Further, JP-A 1-229056 discloses a propylene polymer composition containing a 3-methyl-1-butene polymer in an amount of 0.05 wtppm to 100,000 wtppm, wherein the crystallization temperature of the composition is Disclosed is a polypropylene composition characterized in that it is higher than the crystallization temperature of a propylene polymer containing no 3-methyl-1-butene polymer by 10 ° C. or more.

However, in any of the above methods,
The nucleating agent effect was not sufficient, and improvement was sought. Further, the conventional titanium trichloride-based and magnesium chloride-supporting titanium-based catalysts have a problem that the productivity of the nucleating agent polymer is low.

[0010]

OBJECT OF THE INVENTION The object of the present invention is to improve the molding speed because it has excellent mechanical properties such as rigidity and tensile strength, transparency, surface properties, and high melting point, crystallization temperature and crystallinity. It is an object of the present invention to provide a highly crystalline polypropylene composition and a method for producing the same.

[0011]

The present invention relates to a highly crystalline polypropylene composition having a high melting point and a high crystallization temperature, or a highly crystalline compound containing a nucleating agent polymer obtained by using a metallocene-based polymerization catalyst. Relates to a method for producing a hydrophilic polypropylene composition.

According to the present invention, there is provided a highly crystalline polypropylene composition characterized by containing 10 wtppm to 10,000 wtppm of a nucleating agent polymer in crystalline polypropylene.
Provided is a highly crystalline polypropylene composition characterized in that the ratio Mw / Mn of the weight average molecular weight Mw and the weight average molecular weight Mn of the nucleating agent polymer is 3 or less.

Further, according to the present invention, in a method for producing a highly crystalline polypropylene composition containing 10 wtppm to 10,000 wtppm of a nucleating agent polymer in crystalline polypropylene,
As the nucleating agent polymer, at least one type of monomer selected from branched α-olefins having 4 or more carbon atoms, vinyl group-containing cyclic hydrocarbon compounds, alkenylsilanes, indene compounds, vinyl norbornene and vinyl group-substituted aromatic compounds is metallocene. Provided is a method for producing a highly crystalline polypropylene composition, which comprises using a polymer polymerized using a system polymerization catalyst.

The nucleating agent polymer contained in the crystalline polypropylene of the present invention has a characteristic that the molecular weight distribution is small, and the ratio M of the weight average molecular weight Mw to the weight average molecular weight Mn.
w / Mn is 3 or less. Since the nucleating agent polymer has a small molecular weight distribution, it is possible to obtain a highly crystalline polypropylene composition having a good nucleating agent action, a high crystallization temperature and a high melting point, and excellent rigidity.

In the present invention, two or more kinds of nucleating agent polymers may be mixed and used. In this case, the Mw / Mn of each nucleating agent polymer may be 3 or less, and the Mw / Mn of the nucleating agent polymer after mixing may exceed 3.

The highly crystalline polypropylene composition of the present invention comprises 10 wtppm of a nucleating agent polymer in crystalline polypropylene.
~ 10,000wtppm, more preferably 50wtppm ~ 5,000wtp
Contains pm.

When the content of the nucleating agent polymer is less than the above range, the number of polymer particles forming crystal nuclei is small, and the melting point and crystallization temperature of the obtained polypropylene composition are not sufficiently improved.

When the content of the nucleating agent polymer is more than the above range, the crystallization temperature rises, but there is a problem that the crystallization of the polypropylene composition is hindered and the crystallinity is lowered.

When the melting point of propylene containing no nucleating agent polymer is Tm ₀ and the crystallization temperature is Tc _0, and the melting point of the highly crystalline polypropylene composition of the present invention is Tm and the crystallization temperature is Tc, the present invention In general, Tc ≧ Tc ₀
+5 (° C.) and Tm ≧ Tm ₀ +2 (° C.).

The nucleating agent polymer in the present invention has 4 carbon atoms.
At least one kind of monomer selected from the above branched α-olefins, vinyl group-containing cyclic hydrocarbon compounds, alkenylsilanes, indene compounds, vinyl norbornene and vinyl group-substituted aromatic compounds (hereinafter referred to as a specific monomer) is a metallocene-based compound. It can be produced by polymerization using a polymerization catalyst.

Examples of the branched α-olefin having 4 or more carbon atoms include α-olefins branched at the 3rd or 4th positions. Specific examples of these include branched 1-butene such as 3-methyl-1-butene and 3-ethyl-1-butene, branched 1-pentene such as 3-methyl-1-pentene, and 4-methyl-1-pentene, Four-
Methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-
Examples include branched 1-hexene such as dimethyl-1-pentene, 4-ethyl-1-hexene and 3-ethyl-1-hexene.

Examples of the vinyl group-containing cyclic hydrocarbon compound include vinyl cycloalkane and vinyl cycloalkene. Specific examples thereof include vinylcycloalkanes such as vinylcyclohexane and vinylcycloalkenes such as 4-vinylcyclohexene-1 and 4-vinyl-2-methylcyclohexene-1.

Examples of the alkenylsilane include alkylvinylsilane and alkylallylsilane. Specific examples thereof include alkylvinylsilane such as vinyltrimethylsilane, alkylallylsilane such as trimethylallylsilane, and dimethyldiallylsilane.

Examples of the indene compound include unsubstituted or substituted indene. Specific examples thereof include indene and methylindene.

As the vinyl group-substituted aromatic compound, styrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene,
Examples thereof include alkyl-substituted styrenes such as 3,5-dimethylstyrene, vinylnaphthalene, and vinylanthracene.

In the present invention, a copolymer of two or more of the above specific monomers may be used as the nucleating agent polymer.

The nucleating agent polymer obtained by polymerizing the above-mentioned specific monomer with a metallocene type polymerization catalyst has characteristics such as narrow molecular weight and stereoregular distribution. Further, the copolymer has excellent characteristics such as a narrow comonomer composition distribution. Further, the melting point and crystallization temperature of the polypropylene composition can be increased.

When styrene and alkyl-substituted styrene are polymerized using a metallocene polymerization catalyst, a syndiotactic polymer having a melting point of 260 ° C. or higher is obtained.

Further, vinylcycloalkane and vinylcycloalkene can be obtained as a polymer with high productivity by using a metallocene-based polymerization catalyst.

Among the olefins having 4 or more carbon atoms and branched at the 3-position or the 4-position, a polymer of 3-methyl-1-butene is preferable because it has a high melting point. Also, 3-methyl-1-butene and 4-
A copolymer (eutectic) with methyl-1-pentene is preferable because it has a high melting point and a low production cost.

In the present invention, the metallocene-based polymerization catalyst includes
A metallocene compound of Group IV or V transition metal of the periodic table,
A combination of organoaluminum compounds and / or ionic compounds is used.

As the transition metal of Group IV or V of the periodic table,
Titanium (Ti), Zirconium (Zr), Hafnium (H
f), vanadium (V) and the like are preferable.

The metallocene compound means at least one cyclopentadienyl group and a substituted cyclopentadienyl group (for example, an alkyl-substituted cyclopentadienyl group such as methyl, dimethyl and pentamethyl, an indenyl group,
Fluorenyl group) as a ligand, or a cyclopentadienyl group thereof as a hydrocarbyl group (eg, alkylene group, substituted alkylene group), hydrocarbyl silicon (eg, silanylene group, substituted silanylene group, silaalkylene group, substituted Silaalkylene) and the like, further cyclopentadienyl group is oxygen,
Those bridged to nitrogen or phosphorus atom (for example, oxasilanylene group, substituted oxasilanylene group, oxasilaalkylene group, substituted oxasilaalkylene group, aminosilyl group,
Any known metallocene compound having a monosubstituted aminosilyl group, a phosphinosilyl group, or a monosubstituted phosphinosilyl group) as a ligand can be used.

Specific examples thereof are disclosed in JP-A-58-19309.
No. 60, No. 60-35006, No. 60-35007, No. 61-1
30314, 61-264010, 61-296008, 63-222177, 63-222178, 63-2
22179, 63-251405, JP-A-1-66214, 1-74202, 1-275609, 1-3017.
No. 04, No. 1-319489, No. 2-41303, No. 2-
131488, 3-12406, 3-139504,
3-163088, 3-179006, 3-185005, 3-188092, 3-197514, 3-207703
Gazette, gazette 5-209013 gazette, special table 1-501950 gazette, gazette
Examples thereof include those described in 1-502036 and 5-505593.

In the present invention, it is preferable to use a metallocene-based polymerization catalyst capable of producing a more crystalline specific polymer, which is disclosed in JP-A-61-130314,
61-264010, 63-142004, JP 1-12
9004, 1-301704, 2-75605, and
3-12406, 3-12407, 4-227708, 4-227709, 4-264110, 4-268308
Examples thereof include metallocene compounds described in JP-A Nos. 4-300887 and 6-25343.

These metallocene compounds are themselves
It has a cross-linked and / or polysubstituted ligand capable of forming a complex having a C ₂ symmetry element. Specific examples thereof include dimethylsilyl (2,4-dimethylcyclopentadienyl) (3 ′, 5′-
Dimethylcyclopentadienyl) zirconium dichloride, dimethylsilyl (2,4-dimethylcyclopentadienyl) (3 ', 5'-dimethylcyclopentadienyl) silicon-bridged metallocene compounds such as hafnium dichloride,
Examples thereof include indenyl-based crosslinkable metallocene compounds such as ethylenebisindenylzirconium dichloride, ethylenebisindenylhafnium dichloride, ethylenebis (methylindenyl) zirconium dichloride, and ethylenebis (methylindenyl) hafnium dichloride.

The organoaluminum compound used in the present invention in combination with the metallocene compound has the general formula (-
A linear or cyclic polymer represented by Al (R) O-) _n (R
Is a hydrocarbon group having 1 to 10 carbon atoms, including those partially substituted with a halogen atom and / or an RO group. n is a degree of polymerization, and is 5 or more, preferably 10 or more), and specific examples include methylalumoxane, ethylalumoxane, isobutylethylalumoxane, etc., in which R 2 is a methyl, ethyl, or isobutyl group, respectively. To be

Examples of other organic aluminum compounds include trialkylaluminum, dialkylhalogenoaluminum, sesquialkylhalogenoaluminum, alkenylaluminum, dialkylhydroaluminum and sesquialkylhydroaluminum.

Specific examples thereof include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum and trioctylaluminum, dialkylhalogenoaluminums such as dimethylaluminum chloride and diethylaluminum chloride, sesquimethylaluminum chloride, Examples include sesquialkylhalogenoaluminum such as sesquiethylaluminum chloride, ethylaluminum dichloride, diethylaluminum hydride, and sesquiethylaluminum hydride. These organoaluminum compounds can be used in combination with the above organoaluminum oxy compounds.

Examples of the ionic compound include those represented by the general formula: C ⁺ A
^And C ⁺ is an oxidizing cation of an organic compound, an organometallic compound, or an inorganic compound, or a Bronsted acid composed of a Lewis base and a proton, and reacts with the anion of a metallocene ligand to form a cation of metallocene. Can be generated.

A ^- is a bulky, non-coordinating anion,
The metallocene cation can be stabilized without coordination with the metallocene. Specific examples of these are:
Japanese Patent Application Laid-Open Nos. 4-253711, 4-305585 and Special Publication 5-
Those described in JP-A-507756 and JP-A-5-502906 can be used.

Particularly, an ionic compound of a tetrakis (pentafluorophenyl) borate anion and a triphenylcarbonium cation or a dialkylanilinium cation is preferable. These ionic compounds can be used in combination with the above-mentioned organoaluminum compound.

The metallocene-based polymerization catalyst of the present invention, that is, the metallocene compound, the organic aluminum compound, and / or the ionic compound can be used by being supported on an inorganic compound or an organic polymer compound. As the inorganic compound as a carrier, inorganic oxides, inorganic chlorides and inorganic hydroxides are preferable, and those containing a small amount of carbonates and sulfates can also be adopted. Particularly preferred are inorganic oxides such as silica, alumina, magnesia, titania, zirconia, and calcia.

These inorganic oxides have an average particle size of 5 to
Porous fine particles having a particle size of 150 μ and a specific surface area of ² to 800 m ² / g are preferable, and further heat treated at 100 to 800 ° C., for example.

The organic polymer compound preferably has an aromatic ring, a substituted aromatic ring or a functional group such as a hydroxy group, a carboxyl group, an ester group or a halogen atom in the side chain. Specific examples thereof include α-olefin homopolymers, α-olefin copolymers, acrylic acid, methacrylic acid, vinyl chloride, vinyl alcohol, styrene, and divinylbenzene homopolymers having the functional groups obtained by chemical modification of ethylene, propylene, polybutene, etc. Mention may be made of polymers or copolymers, as well as their chemical modifications.

For these organic polymer compounds, spherical fine particles having an average particle diameter of usually 5 to 250 μm are used. By using a supported catalyst, it is possible to prevent contamination due to the catalyst adhering to the polymerization reactor.

As a method for polymerizing the specific monomer of the present invention using a metallocene-based polymerization catalyst, various well-known methods can be adopted, and fluidized bed gas phase polymerization in an inert gas or stirred gas polymerization can be used. Phase polymerization, slurry polymerization in an inert solvent, bulk polymerization using a monomer as a solvent and the like can be mentioned.

The polymerization of a specific monomer is usually carried out at a polymerization temperature.
10 ~ 150 ℃, preferably 20 ~ 90 ℃, the polymerization time,
Usually, it is 0.1 to 10 hours.

When a metallocene compound and an organoaluminum compound are used as the metallocene-based polymerization catalyst of the present invention, the molar ratio of the aluminum (Al) atom of the organoaluminum compound to the transition metal atom of the metallocene compound (Al / transition metal atom molar ratio) Is usually 10 to 100,000, preferably 10 to 1,000.

As the metallocene polymerization catalyst of the present invention, an ionic compound may be used alone or in combination with the organoaluminum compound instead of the organoaluminum compound.
The ionic compound / transition metal atom molar ratio is usually 0.1 to
It is 50, preferably 0.5 to 5.

The polymerization is usually carried out until a specific monomer polymer of 0.05 to 500 g, preferably 0.2 to 100 g, per 1 mmol of metallocene compound can be produced. The production amount of the polymer can be adjusted by appropriately selecting and controlling the polymerization time and temperature.

The highly crystalline polypropylene composition of the present invention can be produced, for example, by the following method. That is, (1) a method of melt-mixing or solution-mixing a polymer of a specific monomer produced using a metallocene-based polymerization catalyst and a crystalline polypropylene produced separately, (2) using a metallocene-based polymerization catalyst A continuous multi-stage polymerization method in which a specific monomer is polymerized and then propylene is subjected to main polymerization, (3)
A method of melt-mixing or solution-mixing polypropylene containing a small amount of the specific monomer polymer obtained by the method of (2) above and crystalline polypropylene produced separately, (4)
Examples thereof include a method of polymerizing propylene in the presence of a polymer of a specific monomer produced using a metallocene-based polymerization catalyst and a stereoregular polymerization catalyst for propylene polymerization.

The main polymerization of propylene in the continuous multi-stage polymerization method may be the same as the polymerization of the specific olefin or a different polymerization method. That is, a specific monomer is polymerized using a metallocene-based polymerization catalyst in the first stage, unreacted monomers are removed, and then propylene polymerization is performed in the second stage. It is possible to produce a highly crystalline polypropylene composition by a continuous multi-stage polymerization method in which a specific olefin monomer is polymerized by using to remove unreacted monomer, and subsequently, a stereoregular polymerization catalyst is added to carry out propylene polymerization. .

As a stereoregular polymerization catalyst for polymerizing propylene to produce crystalline polypropylene, a catalyst system containing (A) a titanium-containing solid catalyst component and (B) an organoaluminum compound component as main components is used. it can.

Examples of the titanium-containing solid catalyst component which is the component A of the above catalyst system include a solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, or a titanium trichloride solid catalyst component.

Examples of the solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components include a solid catalyst component in which a titanium compound and an electron donor are supported on a magnesium chloride carrier.

As a method for supporting titanium on a magnesium chloride carrier, for example, (1) magnesium halide,
Titanium compound, a method of co-milling an electron donor, (2) a method of treating the three components sequentially in an inert solvent, or a reaction treatment of two or three components simultaneously, (3) magnesium halide, or magnesium halide and An electron donor and a solution of a polar solvent such as ether or alcohol,
A method of precipitating a solid catalyst component by adding a titanium compound, (4) a method of precipitating a solid catalyst component by adding an inert solvent from a solution prepared by dissolving a magnesium halide, a titanium compound, and an electron donor in a polar solvent. Can be manufactured by.

Various methods are known for the preparation of magnesium halide used in the above methods (1) and (2). For example, a method of adding a suitable organic or inorganic halogenating agent to an organomagnesium compound in an ether or an inert hydrocarbon solvent, or adding an inert solvent to a solution of a magnesium halide in a polar solvent such as ether or alcohol. And the like to obtain an activated carrier. The electron donor of the magnesium-containing solid catalyst component is preferably a Lewis base of an organic compound having no acidic proton, particularly preferably an aromatic dicarboxylic acid ester, for example, dibutyl phthalate, butyl ethyl phthalate, hexyl butyl phthalate, diheptyl. Mention may be made of phthalates.

The electron donor of the magnesium-containing solid catalyst component is preferably a Lewis base of an organic compound having no acidic proton, particularly preferably an aromatic dicarboxylic acid ester such as dibutyl phthalate, butyl ethyl phthalate or hexyl butyl phthalate. , Diheptyl phthalate can be mentioned.

In the present invention, the catalyst solid components described in JP-A-60-152511, JP-A-61-31402 and JP-A-62-81405 are particularly preferable for achieving the effects of the present invention. According to the production methods described above, an aluminum halide is reacted with an organosilicon compound such as silicate, and then a magnesium compound is reacted to precipitate a solid. The obtained white solid is contact-treated with an electron donor and a titanium halide compound.

As the titanium-containing solid catalyst component (A),
In addition to the above solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, a titanium trichloride (TiCl ₃ ) solid catalyst component can be used.

As the titanium trichloride solid catalyst component, titanium tetrachloride (TiCl ₄ ) is reduced by various methods, for example, β-type titanium trichloride obtained by reducing titanium tetrachloride with an organic aluminum compound. , Further treated with complexing agent, treated with titanium tetrachloride, reduced titanium tetrachloride with metallic aluminum (1/3 for 1 mol of TiCl ₃
eutectic crystals containing mol AlCl ₃ ) or the like, or a ball-milled / electron-donor-treated product thereof.

As the organoaluminum compound component which is the component B of the above catalyst system, trialkylaluminum,
Examples thereof include dialkylhalogenoaluminum, sesquialkylhalogenoaluminum, alkenylaluminum, dialkylhydroaluminum, sesquialkylhydroaluminum, and organoaluminumoxy compounds.

Specific examples thereof include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum and trioctylaluminum, dialkyls such as dimethylaluminum chloride, diethylaluminum chloride, diisopropylaluminum chloride and diisobutylaluminum chloride. Halogeno aluminum, sesquimethyl aluminum chloride,
Examples include sesquialkylhalogenoaluminum such as sesquiethylaluminum chloride, ethylaluminum dichloride, diethylaluminum hydride, and sesquiethylaluminum hydride.

The organoaluminum oxy compound is a straight-chain or cyclic polymer represented by the general formula (-Al (R) O-) _n (where R is a hydrocarbon group having 1 to 10 carbon atoms, and is partially A halogen atom and / or a group substituted with an RO group are included. N is a degree of polymerization, and is 5 or more, preferably 10 or more), and as specific examples, R 1 is a methyl, ethyl or isobutyl group, respectively. Examples include methylalumoxane, ethylalumoxane, isobutylethylalumoxane, and the like.

When used in combination with a solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, trialkylaluminum is preferable among the above organoaluminum compound components. When used in combination with a titanium trichloride solid catalyst component, dialkylhalogenoaluminum is preferable among the above organoaluminum compound components.

If necessary, an electron donor component may be further combined as the component (C) with the above catalyst system comprising the components (A) and (B). A silicate compound is preferably used as the electron donor component.

As the silicate compound, R ¹ _m R ² _n Si (O
A silicate compound represented by R ³ ) _4-mn can be used. R ¹ , R ² and R ³ are hydrocarbon groups such as an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group and an aryl group, and each may be the same or different. R ¹ has 3 to 3 carbon atoms
8 branched alkyl groups or cycloalkyl groups are preferred. R ³ is preferably a methyl group or an ethyl group. m is usually 0, 1, 2 or 3, with 2 being particularly preferred. n is 0 or 1.

Specific examples of the silicate compound include t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane and di-t-.
Butyldimethoxysilane, diisopropyldimethoxysilane, cyclohexylmethyldimethoxysilane, dicyclohexyldimethoxysilane, dicyclopentyldimethoxysilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-isopentoxysilane , Tetra -n-
Hexoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-butoxysilane,
Methyltriisopentoxysilane, methyltri-n-hexoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltriisopentoxysilane, n-butyltriethoxysilane, isobutyltriethoxysilane, isopentyltriethoxysilane, iso Pentyltri-n-butoxysilane, dimethyldiethoxysilane, dimethyldi-n-butoxysilane, dimethyldiisopentoxysilane, diethyldiethoxysilane, diethyldiisopentoxysilane, diisobutyldiisopentoxysilane, di-n- Butyldiethoxysilane, diisobutyldiisopentoxysilane, trimethylmethoxysilane, trimethylethoxysilane, trimethylisobutoxysilane, triethylisopropoxysilane, tri-n-
Propylethoxysilane, tri-n-butylethoxysilane, triisopentylethoxysilane, phenyltriethoxysilane, phenyltriisobutoxysilane, phenyltriisopentoxysilane, diphenyldiethoxysilane, diphenyldiisopentoxysilane, diphenyldiphenylsilane. Octoxysilane, triphenylmethoxysilane,
Triphenylethoxysilane, triphenylisopentoxysilane, benzyltriethoxysilane, benzyltributoxysilane, dibenzyldiethoxysilane, cyclopentyltrimethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-dimethylcyclopentyltrimethoxysilane , Cyclopentyltriethoxysilane, tricyclopentylethoxysilane, and the like.

In particular, t-butylmethyldimethoxysilane,
Methoxysilanes containing branched hydrocarbon groups such as t-butyl group and diisopropyl group such as t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane, di-t-butyldimethoxysilane, and diisopropyldimethoxysilane, cyclohexylmethyldimethoxysilane Preferred are cyclohexyl group-containing methoxysilanes such as dicyclopentyldimethoxysilane.

Furthermore, various well-known methods can be adopted as a method for polymerizing propylene using the above-mentioned catalyst system containing a titanium-containing solid catalyst component and an organoaluminum compound component as main components, and it is inert. Examples thereof include fluidized bed gas phase polymerization in gas or stirred gas phase polymerization, slurry polymerization in an inert solvent, and bulk polymerization using a monomer as a solvent.

Propylene polymerization is usually carried out at a polymerization temperature of 10 to 15
0 ℃, preferably 20 ~ 90 ℃, the polymerization time is usually 0.1
~ 10 hours.

The molar ratio of the aluminum (Al) atom of the organoaluminum compound to the titanium (Ti) atom of the titanium-containing solid catalyst component (Al / Ti atom molar ratio) is usually 0.5 to 1,00.
0, preferably 1-100.

When an electron donor component, particularly a silicate compound, is used as the third component of the polymerization catalyst, the molar ratio (Si / Al atom) of the silane (Si) atom of the silicate compound and the aluminum (Al) atom of the organic aluminum compound is used. The molar ratio is usually 0.01 to 1, preferably 0.1 to 0.5.

Polymerization is usually carried out until 1 to 100 g, preferably 0.1 to 10 g, of crystalline polypropylene can be produced per 1 g of the titanium-containing solid catalyst component. The production amount of the polymer can be adjusted by appropriately selecting and controlling the polymerization time and temperature.

It is also possible to use hydrogen, diethylzinc or the like as a molecular weight modifier in the polymerization system.

Further, during or after propylene polymerization, propylene and other olefins, for example, acyclic monoolefins such as ethylene, butene-1,4-methylpentene-1, hexene-1, octene-1, and cyclopentene. Cyclic monoolefins such as cyclohexene and norbornene, non-conjugated diolefins such as dicyclopentadiene, 5-ethylidene-2-norbornene, and 1,5-hexadiene can be copolymerized or block copolymerized. From the propylene block copolymer obtained by the latter method, a structural material excellent in impact strength can be produced by melt-mixing with the olefin polymer of the present invention.

As a method of melt-mixing the crystalline polypropylene and the polymer of the specific monomer, a well-known method of melt-mixing an olefin polymer can be adopted. Further, during melt mixing, additives such as heat, light stabilizer, antioxidant, antistatic agent, flame retardant and inorganic filler are usually blended. As a solution mixing method, both polymers are dissolved by heating in a good solvent such as xylene, o-dichlorobenzene, decalin or tetralin, and then a poor solvent such as alcohol or ketone is added to precipitate the polymer.

The highly crystalline polypropylene composition of the present invention is produced by polymerizing propylene in the presence of a nucleating agent polymer consisting of a polymer of a specific monomer obtained with a metallocene polymerization catalyst and a propylene polymerization catalyst. You can also

In the above method, in order to highly disperse the polymer of the specific monomer in polypropylene, the polymer of the specific monomer is mixed with o-dichlorobenzene, decalin,
It is preferable to dissolve and dissolve in an inert solvent such as tetralin and then rapidly cool it, or to use finely divided material by a crusher such as a mill during the subsequent propylene polymerization.

[0081]

The highly crystalline polypropylene composition of the present invention has a high melting point and a high crystallization temperature, and therefore can be used as a structural material having excellent heat resistance and mechanical strength. Further, when formed into a film, the crystal can be made finer by the nucleating agent effect and the transparency can be improved.

[0082]

[Examples] "MI" in the examples means ASTM D-1238
Is a melt index of the polymer measured at 230 ° C. under a load of 2.16 kg / cm ² according to.

The melting point and the crystallization temperature were measured using DSC (Seiko Denshi Kogyo SSC-5200 DSC-220C). The measurement method is to raise the temperature from room temperature to 230 ° C at a rate of 10 ° C / min., Hold for 5 minutes, and then from 230 ° C to 40 ° C.
The temperature was lowered at a rate of 5 ° C / min, and the crystallization temperature was measured. Then, the temperature was further raised from 40 ° C. to 230 ° C. at a rate of 10 ° C./min., And the melting point was measured.

Weight average molecular weight Mw and weight average molecular weight Mn
Is a 150CV GPC manufactured by Waters, o-dichlorobenzene solvent, column SHODEX AT-80M × 2, solvent 145
The molecular weight distribution Mw / Mn was calculated by measurement under the conditions of ° C, sample concentration 0.03 wt% and flow rate 1.0 mL / min.

Isopentad fraction (mmmm)% was measured by using JEOL's EX-400 with a temperature of 130% based on TMS.
° C., the o- dichlorobenzene solvent ¹³ C-NMR spectrum as measured in, Macromolecules 1975 years, Vol. 8, was calculated from the ¹³ C-NMR spectrum were assigned on the basis of the description of the 687 pages.

[0086]

【Example】

Example 1 [Synthesis of poly-3-methyl-1-butene by metallocene catalyst] 5 L of a toluene solution containing 15 M of 3-methyl-1-butene in a 10 L reaction vessel, and a toluene solution of 2 M / L of methylalumoxane 10 mL, Chemistry letter, 1989,
20 mL of a toluene solution containing 10 μM of dimethylsilyl (2,4-dimethylcyclopentadienyl) (3 ′, 5′-dimethylcyclopentadienyl) zirconium dichloride synthesized by the method described on page 1853 was introduced. The temperature of the reaction solution
The temperature was controlled to 40 ° C and the polymerization was performed for 2 hours. The polymer obtained by filtration, separation and drying had a melting point of 295 ° C. Molecular weight distribution M
The w / Mn was 2.3.

[Preparation of polypropylene composition] Japanese Patent Application No. 5
-120219 100 parts by weight of crystalline polypropylene (pentad fraction = 97.0%, MI = 10) produced by the method described in Example 1 and 0.1 parts by weight of the above poly-3-methyl-1-butene (1,000
wtppm) was melt mixed at 200 ° C. for 10 minutes using a Brabender. The melting point of the obtained polypropylene composition is 166.5.
The crystallization temperature was 126.7 ° C.

Example 2 In the preparation of the polypropylene composition of Example 1,
The same operation was performed except that 0.2 part by weight (2,000 wtppm) of -3-methyl-1-butene was used. The melting point of the obtained polypropylene composition was 166.8 ° C, and the crystallization temperature was 127.0 ° C.

Example 3 In the preparation of the polypropylene composition of Example 1,
The same operation was performed except that 0.8 parts by weight (8,000 wtppm) of -3-methyl-1-butene was used. The melting point of the obtained polypropylene composition was 166.7 ° C, and the crystallization temperature was 127.2 ° C.

Example 4 [Poly-3-methyl-1-catalyzed by silica-supported metallocene catalyst]
Synthesis of butene] Toluene 1L, silica 100g, and a toluene solution of 2M / L of methylalumoxane are mixed in an amount of 60 mL to obtain 60
Heat treatment was performed at ℃ for 2 hours. Filtration, separation, toluene 30
After washing 3 times with 0 mL, 1 L of toluene was added again, and 10 mM of dimethylsilyl (2,4-dimethylcyclopentadienyl) (3 ', 5'-dimethylcyclopentadienyl) was added.
Toluene solution containing zirconium dichloride 100m
L was added and heat treatment was performed. Filtration, separation, toluene 300mL
It was washed 3 times with to obtain a supported catalyst. The amount of zirconium supported was 0.5% by weight.

3-Methylbutene was prepared in the same manner as in Example 1 except that 100 mg of this supported catalyst was used as the metallocene catalyst component.
-1 was polymerized to synthesize the polymer. The polymer obtained by filtration, separation and drying had a melting point of 295 ° C. The molecular weight distribution Mw / Mn was 2.6.

[Preparation of Polypropylene Composition] A polypropylene composition was prepared in the same manner as in Example 1 except that O.2 parts by weight (2,000 wtppm) of poly-3-methyl-1-butene was used. The melting point of the composition was 166.8 ° C and the crystallization temperature was 127.0 ° C.

Comparative Example 1 The crystalline polypropylene (pentad fraction = 97.0%, MI = 10) used for blending has a melting point of 164.2 ° C. and a crystallization temperature of
It was 119.3 ° C.

Example 5 [Synthesis of polypropylene composition using silica-supported metallocene catalyst] Polymerization of 3-methylbutene-1 was carried out in the same manner as in Example 2, filtered and separated, and then washed with 300 mL of toluene 5 times. On the other hand, 1 mL of a toluene solution containing 2 mM methylalumoxane was introduced into a 2 L autoclave, 1.2 L of liquid propylene was added, and the temperature of the solution was set to 30 ° C., and then the metallocene catalyst-containing poly-3-methyl-1 was added. -80 butenes
Polymerization of propylene was started by crushing a glass ampoule containing mg, and the polymerization was performed for 10 minutes. The polypropylene obtained contains 2.5% by weight of poly-3-methyl-1-
It contained butene.

[Preparation of Polypropylene Composition] 100% of crystalline polypropylene (pentad fraction = 97.0%, MI = 10)
By weight, 10 parts by weight of the poly-3-methyl-1-butene-containing polypropylene was melt mixed at 200 ° C. for 10 minutes using a Brabender. The melting point of polypropylene composition is 163.8
The crystallization temperature was 128.2 ° C. Poly-3-methyl-1-
The butene content was 2,280 wtppm.

Comparative Example 2 Using the metallocene catalyst supported on silica prepared by the method of Example 2, homopolymerization of propylene was carried out under the polymerization conditions of Example 3. The MI of the crystalline polypropylene was 6.8, the pentad fraction was 94.8%, the melting point was 161.5 ° C, and the crystallization temperature was 120.1 ° C.

Example 6 [Production of Highly Crystalline Polypropylene Composition] A 2 L autoclave was fitted with a glass ampoule containing 7.9 mg of the solid catalyst component described in Example of Japanese Patent Application No. 5-120219, and then triethylaluminum. 2.1 mM, t-butylethyldimethoxysilane 0.35 mM, poly-3-methyl-1-butene o-dichlorobenzene slurry (previously synthesized in Example 1 255 mg poly-3-methyl-1-butene 255 mg It was dissolved in o-dichlorobenzene by heating and rapidly cooled to -50 ° C to make the particles finer), and then hydrogen was added at 2.0 kg / cm ² ,
Subsequently, 1.2 L of liquid propylene was introduced. Then, the inside of the autoclave was cooled to 10 ° C., the glass ampoule was crushed at the start of stirring, and prepolymerized for 10 minutes. Continue to 70
The temperature was raised to ° C and polymerization was carried out for 1 hour. The yield of polypropylene obtained is 250 g, and poly-3-methyl-1-butene
It contained 1,000 wtppm. The MI is 35, the pentad fraction is 96.9%, the melting point is 165.6 ° C, and the crystallization temperature is 127.4.
It was ℃.

Comparative Example 3 In the propylene polymerization of Example 6, poly-3-methyl-1-
The same operation was repeated except that butene was not added. The polypropylene obtained had an MI of 31, a pentad fraction of 97.2%, a melting point of 164.3 ° C and a crystallization temperature of 119.5 ° C.
Met.

Example 7 [Production of Highly Crystalline Polypropylene Composition] Methylalumoxane (2 M / L toluene solution) was placed in a 2 L autoclave.
2.5 mM, silica supported metallocene catalyst (Z
r = 0.004 mM), followed by poly-3-methyl-1-butene o-
Dichlorobenzene slurry (preliminarily 120 mg of poly-3-methyl-1-butene synthesized in Example 4 was added to 15 mL of o-
It was heated and dissolved in dichlorobenzene, rapidly cooled to -50 ° C to make the particles finer, and the mixture was stirred at 20 ° C for 60 minutes.
Then, 1.2 L of liquid propylene was introduced and polymerization was carried out at 40 ° C. for 60 minutes. The yield of polypropylene obtained is 120 g, M.
The I. was 35, the pentad fraction was 95.4%, the melting point was 163.4 ° C, and the crystallization temperature was 129.5 ° C. The content of poly-3-methyl-1-butene was 2,280 wtppm.

Comparative Example 4 In the propylene polymerization of Example 7, poly-3-methyl-1 was used.
-The same operation was performed except that butene was not added.
The polypropylene obtained had an MI of 31, a pentad fraction of 95.7%, a melting point of 161.5 ° C, and a crystallization temperature of 122.5 ° C.

Example 8 In a 500 mL separable flask with a glass filter,
Toluene 250mL, methylalumoxane 5mM, 3-methyl-1
-Butene 40 g and the silica-supported metallocene catalyst (Zr = 0.04 mM) used in Example 2 were charged, and polymerization was carried out at 15 ° C. for 10 minutes. After the polymerization, the liquid phase was filtered and separated, and then washed with a toluene solution of methylalumoxane having a concentration of 5 mM / 250 mL.
Then, a toluene solution containing 5 mM of methylalumoxane 25
0 mL was added to make a slurry. From this slurry Zr =
An amount of 0.004 mM was enclosed in a glass ampoule. Then 2
Attach an ampoule to the L-autoclave, methyl alumoxane (2M / L toluene solution) 2.5 mM, liquid propylene.
1.2 L was introduced and polymerization was carried out at 40 ° C for 60 minutes. The yield of polypropylene obtained was 100 g, the content of poly-3-methyl-1-butene was 100 wtppm, and the pentad fraction was 95.5%.
The melting point was 163.2 ° C and the crystallization temperature was 126.3 ° C.

Comparative Example 5 In Example 3, polymerization of 3-methyl-1-butene was not carried out, and only propylene was polymerized. The polypropylene obtained had a pentad fraction of 95.3%, a melting point of 161.4 ° C, and a crystallization temperature of 121.5 ° C.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichiro Yamada 8-1 Goi Minamikaigan, Ichihara City, Chiba Ube Industries Ltd. Chiba Research Institute

Claims (2)

[Claims] 1. A highly crystalline polypropylene composition containing 10 wtppm to 10,000 wtppm of a nucleating agent polymer in crystalline polypropylene, the ratio Mw / Mn of the weight average molecular weight Mw and the weight average molecular weight Mn of the nucleating agent polymer. Is 3 or less, a highly crystalline polypropylene composition. 2. A method for producing a highly crystalline polypropylene composition containing 10 wtppm to 10,000 wtppm of a nucleating agent polymer in crystalline polypropylene, wherein the nucleating agent polymer contains a branched α-olefin having 4 or more carbon atoms and a vinyl group. Characterized by using a polymer obtained by polymerizing at least one kind of monomer selected from a cyclic hydrocarbon compound, an alkenylsilane, an indene compound, vinyl norbornene, and a vinyl group-substituted aromatic compound using a metallocene-based polymerization catalyst system. A method for producing a highly crystalline polypropylene composition.