JPH11130922A - Low crystalline polypropylene resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the flexibility, transparency, heat resistance, moldability and impact resistance of the title composition by employing a certain low crystalline polypropylene and an organic and/or a polymer nucleating agent. SOLUTION: 100 pts.wt. of a low crystalline polypropylene is compounded with 0.01-1 pts.wt. of an organic nucleating agent and/or 1-1,000 wt.ppm of a polymer nucleating agent. The low crystalline polypropylene comprises a polypropylene homopolymer or a propylene-α-olefin copolymer containing not more than 5 mol.% of an α-olefin other than propylene, and has a melt flow rate of 1-20 g/10 min. and a molecular weight distribution (Mw/Mn) of 3-14, preferably 4-12. When fractionated by programmed fractional dissolution, the low crystalline polypropylene gives 5-35 wt.%, preferably 10-30 wt.% of elution at below 20 deg.C of, 40-80 wt.%, preferably 50-70 wt.% of elution at 100 deg.C or higher, and 10-40 wt.%, preferably 10-30 wt.%. of elution between 20 deg.C inclusive and below 100 deg.C in an elution curve with the abscissa and the ordinate respectively showing elution temperature ( deg.C) and integrated weight ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a low-crystalline polypropylene resin composition having good flexibility, transparency, heat resistance, moldability, and particularly excellent impact resistance.

[0002]

2. Description of the Related Art Polypropylene is widely used for industrial parts, sheets, films and the like because of its excellent moldability, rigidity and heat resistance. However, conventionally used so-called isotactic polypropylene, which has high crystallinity, is excellent in rigidity and heat resistance, but is inferior in flexibility, impact resistance and transparency. Many means have been proposed to remedy these drawbacks. For example, in order to improve impact resistance, a method of randomly copolymerizing propylene and another α-olefin, or a method of copolymerizing propylene and ethylene followed by propylene and ethylene to form a block copolymer are known. Have been. However,
When a random copolymer is used, impact resistance and transparency are improved, but there is a problem that the heat resistance is impaired because the melting point is significantly reduced. Further, when a block copolymer is used, there is a problem that the impact resistance and the heat resistance are excellent, but the transparency is significantly reduced.

[0003] On the other hand, a method of reducing stereoregularity in order to impart flexibility to polypropylene is also known. For example, Japanese Unexamined Patent Publication (Kokai) No. 59-122506 proposes a polypropylene having a wide molecular weight distribution, a relatively high melting point, and flexibility, and low stereoregularity. However, in this method, when the melt flow rate is relatively high, the impact resistance is significantly reduced, and there is still room for improvement in the balance between flexibility and heat resistance. It has been desired that flexible polypropylene also has high heat resistance.
Also, JP-A-6-263934 proposes a polypropylene excellent in rubber elasticity by containing an atactic component having a specific viscosity, but the obtained polypropylene has a relatively low melt flow rate, There is still room for improvement in formability.

As a method for solving this problem, Japanese Patent Application Laid-Open No.
JP-A-157606 proposes a method for adjusting the melt flow rate by melt-kneading low stereoregularity polypropylene having a weight average molecular weight of 1,000,000 or more in the presence of an organic peroxide. Even there, there was still room for improvement in impact resistance.

On the other hand, various methods have been proposed to greatly improve the transparency of polypropylene by adding a crystal nucleating agent to polypropylene, but in this case, flexibility is significantly impaired due to the improvement in the crystallinity of polypropylene. There was a problem that.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide excellent flexibility, transparency, heat resistance and moldability, and particularly excellent impact resistance, and a good balance of these properties. To provide a low-crystalline polypropylene resin composition.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, by adding a specific nucleating agent to a low crystalline polypropylene having a specific crystallinity distribution. It has been found that, without significantly impairing the flexibility of the low crystalline polypropylene, in addition to the effect of improving the transparency by the addition of a crystal nucleating agent, the impact resistance is surprisingly dramatically improved. Completed the invention.

That is, the present invention relates to a propylene homopolymer or a copolymer of propylene and an α-olefin having an α-olefin other than propylene of 5 mol% or less, and (1) a melt flow rate of 1 to 20 g. / 10 minutes,
(2) In the elution curve represented by the elution temperature (° C.) on the horizontal axis and the integrated weight ratio of the elution components, the elution component at less than 20 ° C. (component A) ) Is from 5 to 35% by weight, and the amount of the component (B component) eluted at 100 ° C. or higher is from 40 to 80% by weight, and 100 parts by weight of the low crystalline polypropylene is used in an amount of 0.01% by weight of the organic crystal nucleating agent. ~
1 part by weight, and / or 1 to 1000
It is a low crystalline polypropylene resin composition characterized in that it is contained in a ratio of ppm by weight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The low-crystalline polypropylene of the present invention is a polypropylene homopolymer or a copolymer of propylene and an α-olefin having an α-olefin other than propylene of 5 mol% or less (hereinafter referred to as propylene- α-olefin copolymer).

In the present invention, α-olefins other than propylene include, for example, ethylene, 1-butene,
-Pentene, 1-hexene, 1-heptene, 1-octene, 3-methyl-1-butene, 4-methyl-1-pentene and the like. When the α-olefin content in the propylene-α-olefin copolymer exceeds 5 mol%, heat resistance is impaired due to a decrease in melting point, which is not preferable.

In the low crystallinity polypropylene of the present invention, if the melt flow rate is less than 1, molding processability becomes difficult, and if it exceeds 20, the melt tension decreases,
In particular, molding processability in extrusion molding is unpreferably reduced.

The melt flow rate of the low crystalline polypropylene of the present invention is approximately 200,000 when converted into a weight average molecular weight by gel permeation chromatography.
It is in the range of 500,000.

In the present invention, the elevated temperature elution fractionation method refers to, for example, Journal of Applied Pol
ymer Science; Applied Poly
mer Symposium 45, 1-24 (199
0) is described in detail. First, a high-temperature polymer solution is introduced into a packed column using diatomaceous earth as a filler, and the temperature of the column is gradually decreased to crystallize the filler surface in order from the component with the higher melting point, and then the column temperature is gradually increased. In this method, the components are eluted in order from the component having the lowest melting point to separate the eluted polymer components. In the present invention, as shown in the Examples, SSC-7300 manufactured by Senshu Kagaku Co., Ltd. was used as a measuring device, and a solvent:
O-dichlorobenzene, flow rate: 2.5 ml / min, heating rate: 4 ° C./Hr, column: φ30 mm × 300 mm
Shows the values measured under the conditions.

20 ° C. of the low crystalline polypropylene of the present invention
The eluted component (A component) with less than the above is a component necessary especially for developing flexibility. That is, if the amount of the component A is less than 5% by weight, flexibility is impaired, and if it exceeds 35% by weight, sufficient heat resistance cannot be obtained, which is not preferable.
In order to exhibit more excellent flexibility and heat resistance, the amount of the component A is particularly preferably in the range of 10 to 30% by weight.

The low crystallinity polypropylene of the present invention, 100
The component eluted at a temperature of not less than ° C. (component B) is a component necessary for obtaining the excellent heat resistance characteristic of the present invention. That is, when the amount of the B component is less than 40% by weight, the heat resistance of a molded article is impaired, and the amount of the B component is 8%.
If it exceeds 0% by weight, the flexibility is impaired, which is not preferred. In consideration of flexibility and heat resistance, the amount of the component B is preferably more than 50% by weight and 70% by weight or less. In order to obtain more excellent heat resistance, it is preferable that the peak top temperature of the component B is 120 ° C. or higher.
It is preferable that the component is a highly crystalline polypropylene component having a weight percent or more.

20 ° C. of the low crystalline polypropylene of the present invention
The amount of the eluted component (C component) at a temperature of less than 100 ° C. is preferably in the range of 10 to 40% by weight in consideration of achieving a better balance between transparency, flexibility and heat resistance. If the amount of the component C is less than 10% by weight, good transparency and flexibility cannot be achieved when a molded article is obtained.
If the content exceeds 10% by weight, heat resistance will be insufficient. In order to achieve a better balance between transparency, flexibility and heat resistance, the amount of the component C is particularly preferably in the range of 10 to 30% by weight.

The weight ratio (C / A) of the amount of the component C to the amount of the component A of the low crystallinity polypropylene of the present invention is preferably 0.6 or more, and the better balance between transparency, flexibility and heat resistance. Is preferable, and it is particularly preferably 0.7 or more.

The weight average molecular weight (Mw) and the number average molecular weight (Mw) of the low crystalline polypropylene of the present invention measured by gel permeation chromatography (GPC).
The molecular weight distribution (Mw / Mn) represented by the ratio n) is preferably 3 or more and 15 or less in order to obtain excellent moldability. When the molecular weight distribution is less than 3, the moldability decreases, and when the molecular weight distribution exceeds 15, the anisotropy of the orientation of the resin after molding increases, and not only the balance of warpage, shrinkage, etc. of the molded product decreases, It is not preferable because impact resistance is also reduced. A particularly preferred range of the molecular weight distribution is from 4 to 12.

The low-crystalline polypropylene of the present invention has a weight-average molecular weight (Mw) determined by gel permeation chromatography (GPC) of 10,000 or less in the weight-average molecular weight (Mw). It is preferable for suppressing stickiness.

The molecular weight distribution (Mw / Mn) of each of the components A, B and C of the low crystalline polypropylene of the present invention.
Is preferably 3 or more and 15 or less in order to obtain good moldability.

The low crystalline polypropylene resin composition of the present invention preferably has a melting point measured by differential scanning calorimetry (DSC) of 150 ° C. or more and a heat of fusion of 100 J / g or less. When the melting point is less than 150 ° C,
Sufficient heat resistance cannot be obtained and the heat of fusion is 100 J / g
If it exceeds, flexibility is impaired, which is not preferred.

The low crystalline polypropylene resin composition of the present invention preferably has a heat distortion temperature of 50 ° C. or higher, which is determined by a measuring method according to JIS K7207.

The method for producing the low-crystalline polypropylene of the present invention is not particularly limited as long as it satisfies the requirements of the present invention. For example, it can be obtained by the following method.

The following catalyst components [A], [B], [C] [A] Titanium compound [B] General formula R ¹ _n AlX _3-n (where R ¹ is a saturated hydrocarbon group having 1 to 10 carbon atoms) , X is a halogen atom, and n is an integer of 0 to 3) [C] Formula (I) R ² _{n / 2} Al (OR ³ ) _{3-n / 2} (I) (where, R ² and R ³ are the same or different and are a saturated hydrocarbon group having 1 to 10 carbon atoms, n is an integer of 1 to 4) or a compound of the general formula (II)

[0025]

Embedded image

(Where R ⁴ is an alkyl group, an aryl group or a halogen atom, R ⁵ , R ⁶ and R ⁷ are a hydrogen atom, an alkyl group or an aryl group, and n is 0 <n <
3. In the presence of the organoalkoxyaluminum compound represented by the formula (1), firstly, homopolymerization of propylene or copolymerization of propylene with another α-olefin is carried out in the absence or presence of hydrogen in the first step. As a step, in the presence of the components [A], [B], and [C], an electron donor compound [D] is further added to carry out a second step of polymerization. This is a method for increasing the hydrogen concentration.

As the titanium compound [A], a titanium compound known to be used for the polymerization of olefin is used without any limitation. These titanium compounds are roughly classified into a supported titanium compound and a titanium trichloride compound. As a method for producing the supported titanium compound, a known method is employed without any limitation. For example, Japanese Patent Application Laid-Open Nos. 56-155206 and 56
-136806, 57-34103, 58-870
6, 58-83006, 58-138708, 5
8-183709, 59-206408, 59-2
19311, 60-81208, 60-8120
9, 60-186508, 60-192708, 61-211309, 61-271304, 62-
15209, 62-11706, 62-7270
2, the methods shown in 62-104810 and the like are adopted.

Specifically, for example, a method in which titanium tetrachloride is co-ground with a magnesium compound such as magnesium chloride, a method in which a titanium halide is mixed with a magnesium compound in the presence of an electron donor such as an alcohol, ether, ester, ketone or aldehyde. And a method of contacting a titanium halide, a magnesium compound and an electron donor in a solvent. Examples of the titanium trichloride compound include known α, β, γ, and δ-titanium trichloride. Methods for preparing these titanium trichloride compounds are described, for example, in JP-A-47-34478,
126590, 50-114394, 50-938
88, 50-123091, 50-74594, 50-104191, 50-98489, 51-1
36625, 52-30888, 52-35283
Etc. are adopted.

Next, as the organoaluminum compound [B], a compound known to be used for polymerization of olefins is employed without any limitation. For example, trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, tri-i-
Butyl aluminum, tri-n-hexyl aluminum, tri-n-octyl aluminum, trialkyl aluminums such as tri-n-decyl aluminum or diethyl aluminum monochloride, diethyl aluminum monohalides such as diethyl aluminum bromide or methyl aluminum sesquichloride, Examples thereof include alkyl aluminum halides such as ethyl aluminum sesquichloride and ethyl aluminum dichloride.

The organic alkoxyaluminum compound [C] is a reaction product of an alkylaluminum or an alkylaluminum halide with an alcohol, and the organic alkoxyaluminum compound represented by the above general formulas (I) and (II) does not contain any compound. Adopted without restrictions.

Examples of the organic alkoxyaluminum compound represented by the general formula (I) include dimethylaluminum methoxide, dimethylaluminum ethoxide, dimethylaluminum isopropoxide, diethylaluminum methoxide, diethylaluminum ethoxide,
Examples thereof include diethylaluminum-n-butoxide, methylaluminum sesquimethoxide, methylaluminum sesquiethoxide, ethylaluminum sesquiethoxide, ethylaluminum diethoxide, diisobutylaluminum ethoxide, and ethylaluminum chloride monoethoxide.

As the organic alkoxyaluminum compound represented by the general formula (II), for example, dimethylaluminum phenoxide, dimethylaluminum (2-
Methylphenoxide), dimethylaluminum (2,4
-Dimethylphenoxide), dimethylaluminum (2,6-dimethylphenoxide), dimethylaluminum (2,4,6-trimethylphenoxide), dimethylaluminum (2,6-diisopropylphenoxide), dimethylaluminum (2,6-di-t) -Butylphenoxide), dimethylaluminum (2,6-diphenylphenoxide), diethylaluminum phenoxide, diethylaluminum (2-methylphenoxide), diethylaluminum (2,4-dimethylphenoxide), diethylaluminum (2,6-dimethylphenoxide) , Diethylaluminum (2,4,6-trimethylphenoxide), diethylaluminum (2,4,6-trimethylphenoxide)
6-diisopropylphenoxide), diethyl aluminum (2-isobutyl phenoxide), diethyl aluminum (2-t-butyl phenoxide), diethyl aluminum (2,6-di-t-butyl phenoxide), diethyl aluminum (2,6-di- t-butyl-4-methylphenoxide), diethylaluminum (2,6-
Diphenylphenoxide) and the like.

Further, as the electron donor compound [D], a compound known to be used for improving the stereoregularity of an olefin is employed without any limitation. For example, methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, isopropyl alcohol,
Alcohols such as isoamyl alcohol, phenol,
Phenols such as cresol, cumylphenol, xylenol and naphthol; ketones such as acetone, methyl ethyl ketone, acetophenone and benzophenone; aldehydes such as acetaldehyde, propionaldehyde and benzaldehyde; methyl formate, methyl acetate, ethyl acetate, butyl acetate and acetic acid Organic acids such as vinyl, methyl propionate, ethyl propionate, ethyl valerate, ethyl stearate, ethyl acrylate, methyl methacrylate, ethyl benzoate, methyl toluate, methyl anisate, ethyl phthalate, methyl carbonate, butyrolactone Esters, methyl ether, ethyl ether, isopropyl ether, isoamyl ether, tetrahydrofuran, anisole, ethers such as diethylene glycol dimethyl ether, vinegar Amide, amide benzoate, acid amides such as maleic acid amide, methylamine, ethylamine, piperidine, pyridine, amines such as aniline,
Acetonitrile, nitriles such as benzonitrile, dimethyldimethoxysilane, diethyldimethoxysilane, ethyl silicate, divinyldimethoxysilane, diallyldimethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, methyltriethoxysilane,
Ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, pentyltriethoxysilane, isopropyltriethoxysilane, cyclohexylmethyldimethoxysilane, di-t-butyldimethoxysilane, t-butylethyldimethoxysilane, di-t-amyldimethoxysilane , Dicyclopentyldimethoxysilane, dicyclohexyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylethyldimethoxysilane, cyclopentylisobutyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylethyldimethoxysilane, cyclohexyl Examples of organosilicon compounds such as isobutyldimethoxysilane It is possible. Further, a plurality of these electron donor compounds can be used at the same time.

The titanium compound [A] used in the present invention,
The combination of the organoaluminum compound [B], the organoalkoxyaluminum compound [C] and the electron donor [D] is as follows: (1) supported titanium compound-trialkylaluminum-organoalkoxyaluminum compound-electron donor (2) trichloride Titanium compound-diethylaluminum monohalide-organoalkoxyaluminum compound-electron donor (3) titanium trichloride compound-trialkylaluminum-organoalkoxyaluminum compound-electron donor; and (4) supported titanium compound-titanium trichloride compound The combination of -trialkylaluminum-organoalkoxyaluminum compound-electron donor is particularly preferable because it satisfies the constitution of the low crystalline polypropylene of the present invention in combination with other production conditions.

In the present invention, prior to the main polymerization in the presence of each of the above-mentioned components, pre-polymerization with propylene or another α-olefin in the presence of the same component can be carried out by subjecting the resulting polymer powder to particles. This is suitable because the properties can be made high fluidity.

In the prepolymerization, in addition to the system using [A] and [B], and if necessary, [D],
It is also possible to add an iodine compound [E] represented by the following general formula (I) for the purpose of reducing the amount of low molecular weight components produced in the low stereoregularity polypropylene obtained by the main polymerization.

[E] Iodine compound RI (I) (where R is an iodine atom or an alkyl group having 1 to 7 carbon atoms or a phenyl group) The amount of each of these components used in the prepolymerization is as follows: Type of catalyst,
Since the amount varies depending on the polymerization conditions, the optimum amount to be used may be determined in advance according to each of these conditions. An example of a generally preferred range is as follows.

That is, the ratio of the organoaluminum compound [B] used in the prepolymerization is 0.1 to 100, preferably 0.1 to 20 in terms of Al / Ti (molar ratio) with respect to the titanium compound [A]. The organoalkoxyaluminum compound [C] used if necessary is 0.01 to [C] / Ti (molar ratio) with respect to the titanium compound [A].
100, preferably in the range of 0.01 to 10, and the proportion of the electron donor compound [D] used is the titanium compound [A].
0.01 to 100 in [D] / Ti (molar ratio),
Preferably, the range of 0.01 to 10 is suitable. Further, an iodine compound [E] optionally used
Is in the range of 0.1 to 100, preferably 0.5 to 50 as I / Ti (molar ratio) with respect to the titanium compound [A].

Specific examples of the iodine compound which can be suitably used in the prepolymerization of the present invention are as follows. For example, iodine, methyl iodide, ethyl iodide, propyl iodide,
Butyl iodide, iodobenzene, p-iodine toluene and the like. Particularly, methyl iodide and ethyl iodide are preferred.

The amount of prepolymerization for polymerizing the α-olefin in the presence of the catalyst component varies depending on the prepolymerization conditions.
Generally, a range of 0.1 to 500 g / g · Ti compound, preferably 1 to 100 g / g · Ti compound, is sufficient. The α-olefin used in the prepolymerization may be propylene alone, and other α-olefins such as ethylene, 1-butene, 1-pentene, 1-hexene, 3-hexene, and so forth may be used without adversely affecting the physical properties of the polymerization powder. -Methyl-1-butene, 4-methyl-1-pentene, etc. may be polymerized alone or as a mixture with propylene. The prepolymerization may be performed in multiple stages, and different olefin monomers may be prepolymerized in each stage. It is also possible to make hydrogen coexist at each prepolymerization stage.

In the prepolymerization, slurry polymerization is usually preferably applied. As a solvent, a saturated aliphatic hydrocarbon or an aromatic hydrocarbon such as hexane, heptane, cyclohexane, benzene or toluene is used alone, or a mixed solvent thereof. Can be used.

The prepolymerization temperature is preferably in the range of -20 to 100 ° C, particularly preferably 0 to 60 ° C. The pre-polymerization time may be appropriately determined according to the pre-polymerization temperature and the amount of polymerization in the pre-polymerization, and the pressure in the pre-polymerization is not limited, but in the case of slurry polymerization, generally, the pressure is from atmospheric pressure to 5 kg / c.
It is about m2G. The prepolymerization may be performed in any of batch, semi-batch, and continuous methods.

The main polymerization is carried out after the preliminary polymerization. In the main polymerization of the low crystalline polypropylene of the present invention, it is preferable to perform the main polymerization by multi-stage polymerization of two or more stages under different conditions in order to satisfy a specific crystallinity distribution.

The amount of the organoaluminum compound [B] used in the first stage of the main polymerization is Al / Ti (molar ratio) based on titanium atoms in the titanium compound-containing prepolymer.
In the range of 1 to 1000, preferably 2 to 500. The amount of the organic alkoxyaluminum compound [C] to be used is 0.01 to 10 mol, preferably 0.1 to 10 mol, per 1 mol of the organic aluminum compound [B]. Further, the electron donor [D] used in the second stage of the main polymerization is used in an amount of 0.001 to 10 mol, preferably 0.01 to 10 mol, per 1 mol of the organoaluminum compound [B] used in the first stage. １1 mol.

In the first stage polymerization, the titanium compound-containing prepolymer obtained by the prepolymerization and the above-mentioned [B],
The order of addition of [C] to the polymerization system is not particularly limited, and a mixture in which the respective components are mixed in advance may be used.

The polymerization of propylene in the first stage is carried out in the absence or presence of hydrogen by supplying propylene alone or a mixture of propylene and another α-olefin within a range satisfying the requirements of the present invention. Then, the second stage polymerization may be carried out by adding the electron donor compound [D] and hydrogen.

In the present invention, it is preferable to carry out the polymerization in the first stage and the second stage under different hydrogen concentrations. In the second stage polymerization, by increasing the hydrogen concentration more than in the first stage, a component having a lower molecular weight than the polymer to be polymerized in the first stage is polymerized. Further, the electron donor added in the second stage increases the crystallinity of the polymer polymerized in the second stage more than the polymer in the first stage. Stereoregular polypropylene is obtained.

In the present invention, when the first-stage polymerization is carried out in the presence of hydrogen, the first-stage polymerization is carried out in order to reduce the fluidity and low-molecular-weight components of the resulting low stereoregularity polypropylene polymer. It is preferable to set the hydrogen concentration so that the weight average molecular weight of the polymer is 700,000 or more.

To illustrate typical conditions for the propylene polymerization in the first and second stages, the polymerization temperature is 80 ° C. or less,
Further, it is preferable to adopt from a range of 20 to 70 ° C. Further, the polymerization may be any method such as slurry polymerization using propylene itself as a solvent, gas phase polymerization, solution polymerization and the like. Considering the simplicity of the process, the reaction rate, and the particle properties of the produced polymer powder, slurry polymerization using propylene itself as a solvent is a preferred embodiment. The polymerization system may be any of a batch system, a semi-batch system, and a continuous system.

After completion of the main polymerization, the monomer is evaporated from the polymerization system to obtain the low crystalline polypropylene of the present invention. This low-crystalline polypropylene can be subjected to known washing or countercurrent washing with a hydrocarbon having 7 or less carbon atoms.

The method for producing low-crystallinity propylene of the present invention is not limited to the above-mentioned polymerization method, but may be obtained by blending a high-crystallinity polypropylene and a low-crystallinity polypropylene separately obtained by polymerization as long as the requirements of the present invention are satisfied. However, in order to obtain good transparency, it is a preferable embodiment to produce by a polymerization method.

As the organic crystal nucleating agent and the polymer crystal nucleating agent used as the crystal nucleating agent in the present invention, known ones can be used without any limitation.

When the nucleating agent is added to the low-crystalline polypropylene of the present invention, the flexibility of the low-crystalline polypropylene is not significantly impaired, the effect of improving transparency is improved, and surprisingly, the impact resistance is improved. Dramatically improved. When a crystal nucleating agent is added to conventional polypropylene, the rigidity, heat resistance, and transparency are improved, but the effect of improving impact resistance is hardly confirmed. By adding the above specific nucleating agent to crystalline polypropylene, a remarkable effect of improving impact resistance was recognized. Although the reason why the effect of improving the impact resistance of the present invention has been developed is not yet clear, the present inventors have found that by adding a specific crystal nucleating agent to a low-crystalline polypropylene having a specific crystallinity distribution. It is presumed that impact resistance was improved due to the involvement of fine spherulites and amorphous components.

The nucleating agent used in the present invention is
In the compounding range, it is preferable to increase the crystallization temperature of the low-crystalline polypropylene of the present invention by 5 ° C. or more,
In particular, those which raise the temperature by 10 ° C. or more are more preferable.

In the present invention, examples of the suitable organic crystal nucleating agent include an organic phosphorus compound, a dibenzylidene sorbitol compound, a metal benzoate, and a rosin compound. Specific examples of these organic crystal nucleating agents include, for example, sodium-2,2'-methylene-bis (4,6-di-t-
Butylphenyl) phosphate, sodium-2,2 '
-Ethylidene-bis (4,6-di-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate,
Lithium-2,2'-ethylidene-bis (4,6-di-
t-butylphenyl) phosphate, calcium-bis- [2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate], magnesium-bis-
[2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate], aluminum-tris-
[2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate], bis (2,4,8,10-
Tetra-t-butyl-hydroxy-12H-dibenzo [d, g] [1,3,2] dioxaphosphin-6-oxide) aluminum hydroxide, 2,2′-methylenebis (4,6-di-t) -Butylphenyl) phosphate basic aluminum salt and the like.

Examples of the dibenzylidene sorbitol compound include 1,3,2,4-dibenzylidene sorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, and di (p-ethylbenzylidene) sorbitol. , Di (dimethylbenzylidene) sorbitol,
Mono (p-methylbenzylidene) sorbitol, 1.3
-P-chlorobenzylidene 2.4-p-methylsorbitol and the like.

Examples of the metal benzoate include aluminum hydroxy-pt-butyl benzoate, sodium benzoate and the like.

Examples of the rosin compound include dehydroabietic acid, sodium dehydroabietic acid, potassium dehydroabietic acid, magnesium dehydroabietic acid, aluminum dehydroabietic acid, dihydroabietic acid, sodium dihydroabietic acid, potassium dihydroabietic acid, and the like. Examples thereof include magnesium dihydroabietic acid and aluminum dihydroabietic acid.

Among these organic crystal nucleating agents, sodium-2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate, bis (2,2 4,8,10-tetra-t-butyl-
Hydroxy-12H-dibenzo [d, g] [1,3
2] dioxaphosphin-6-oxide) aluminum hydroxide, di (p-methylbenzylidene) sorbitol,
Aluminum hydroxy-pt-butyl benzoate is particularly preferred.

In the present invention, examples of the preferred polymer crystal nucleating agent include poly-3-methyl-1-butene,
Poly-3-methyl-1-pentene, poly-4-methyl-
Examples thereof include 1-pentene, poly-4,4-dimethylpentene, poly-4,4-dimethylhexene, polycyclopentene, polyvinylcyclohexane, polyallyltrimethylsilane, and polyvinylpyridine. Among them, in order to improve impact resistance, , Poly-3-methyl-1-butene and polyvinylcyclohexane are particularly preferred.

The method of adding the high molecular weight nucleating agent in the present invention is not particularly limited.
A method in which these monomers are polymerized as an olefin or in place of an α-olefin, or a method in which these monomers are separately polymerized and added separately, are generally used.

The amount of the organic crystal nucleating agent used in the present invention is 0.01 to 1 with respect to 100 parts by weight of polypropylene.
Parts by weight, preferably 0.03 to 0.5 parts by weight. That is, when the amount is less than 0.01 part by weight, the effect of improving transparency and impact resistance is not sufficient, and when the amount exceeds 1 part by weight, the effect of improving physical properties corresponding to the amount is sufficiently exhibited. It is not preferable because it is not performed.

The amount of the polymer nucleating agent used in the present invention is 1 to 100 parts by weight per 100 parts by weight of polypropylene.
0 ppm by weight, preferably 3 to 500 ppm by weight. That is, if the amount is less than 1 ppm by weight, the effect of improving transparency and impact resistance is not sufficient, and if it exceeds 1000 ppm, the effect of improving physical properties corresponding to the amount is not sufficiently exhibited. Not preferred.

In the present invention, the organic crystal nucleating agent and the polymer crystal nucleating agent may be used in combination of a plurality of nucleating agents of each type, May be used in combination within the above range.

In addition, an antioxidant, a heat stabilizer, a chlorine scavenger,
Light stabilizers, lubricants, anti-blocking agents, antistatic agents,
After adding and mixing commercially available additives such as flame retardants and pigments,
The pellets may be used in an extruder. Further, an organic peroxide may be added in addition to the above additives to adjust the molecular weight within a range satisfying the requirements of the present invention.

[0066]

The low-crystalline propylene resin composition of the present invention has moderate flexibility, good transparency, heat resistance, good moldability, and extremely excellent impact resistance. It can be suitably used in various fields where a plastic elastomer is used. For example, in the field of injection molding, bumpers, mudguards, and lamp packings for automobile parts, and in the field of home appliances, various packings, ski shoes, grips, and roller skates. On the other hand, in the extrusion molding field, various automotive interior materials,
Suitable for use as various insulation sheets, covering materials for cords and waterproofing sheets, waterproof materials, joint materials, stretch films for packaging, various transparent sheets as substitutes for polyvinyl chloride, etc. it can.

[0067]

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples. The measurement method used in the following examples will be described.

(1) Elevated Temperature Elution Separation Method SSC-7300 manufactured by Senshu Scientific Co., Ltd. was used under the following measurement conditions.

Solvent; O-dichlorobenzene flow rate; 2.5 ml / min heating rate; 4 ° C./Hr sample concentration; 0.7 wt% sample injection amount; 100 ml detector; infrared detector, wavelength 3.41 μm column; φ30 mm × 300 mm Filler; Chromosorb P 30-60 mesh Column cooling rate; 2.0 ° C./Hr (2) Melt flow rate (hereinafter abbreviated as MI) Based on ASTM D-1238.

(3) Molecular weight distribution P. It was measured by the C (gel permeation chromatography) method. Sensyu Science SSC-7
Using o-dichlorobenzene as solvent, 135
C. was performed. The column used was Shodex UT80.
7, 806M. The calibration curve is a standard sample having a weight average molecular weight of 950, 2900, 10,000, 50,000 and 49.8.
Were prepared using 10,000, 2.7, and 4.9 million polystyrene.

(4) Crystallization temperature From a molten state by a differential scanning calorimeter (DSC), 10 ° C. /
After cooling in minutes, the crystallization exothermic peak temperature was measured.

(5) Flexural modulus According to ASTM D-790.

(6) Izod impact strength According to JIS K7110.

(7) Transparency (Haze value) A test piece having a thickness of 1 mm was prepared by injection molding, and was subjected to JIS.
K6714.

(8) Heat Deformation Temperature Based on JIS K7207.

Example 1 (Preliminary polymerization) A 1-liter glass autoclave reactor equipped with a stirrer was sufficiently replaced with nitrogen gas, and then 400 ml of heptane was charged. Reactor temperature 2
After keeping at 0 ° C., 0.18 mmol of butyl acetate, 22.7 mmol of ethyl iodide, 18.5 mmol of diethylaluminum chloride, and 22.7 mmol of titanium trichloride (manufactured by Marubeni Solvay Chemical Co., Ltd.) were added, and then propylene was added to 1 g of titanium trichloride. The reactor was continuously introduced into the reactor at a rate of 3 g per 30 minutes. The temperature during this period was kept at 20 ° C. After stopping the supply of propylene, the inside of the reactor was sufficiently replaced with nitrogen gas, and the obtained titanium-containing polypropylene was washed four times with purified n-hexane. As a result of the analysis,
2.9 g of propylene was polymerized per 1 g of titanium trichloride.

(Main Polymerization) In a 2 liter autoclave substituted with N ₂ , 1 liter of liquid propylene, 0.70 mmol of diethyl aluminum chloride, ethyl aluminum sesquiethoxide (Et _1.5 Al (OE
t) _1.5 ) 0.70 mmol was added, and the internal temperature of the autoclave was raised to 70 ° C. The titanium compound-containing polypropylene obtained by the prepolymerization was converted to titanium trichloride by 0.08.
7 mmol was added, and propylene was polymerized at 70 ° C. for 2 hours (first stage). Next, butyl acetate 0.014mmo
1 was added, hydrogen was inserted so that the concentration in the gas phase became 1.7 mol%, and polymerization was performed for 1 hour (second stage).

The unreacted monomer was purged to obtain a polymer. The obtained polymer was dried under reduced pressure at 70 ° C. for 1 hour.
Next, an antioxidant, a heat stabilizer, a chlorine scavenger and a nucleating agent of the kind and amount shown in Table 2 were added and mixed.
Extruded at 230 ° C using an mφ extruder into pellets,
It was subjected to physical property measurement. The results are shown in Tables 1 and 2. FIG. 1 shows an elution curve obtained by a temperature separation method.

Examples 2 to 5 In the granulation of Example 1, 0.02% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene (Example 2) and 0.05% by weight of Example 3 (Example 3) 5) used, Table 2
The same operation as in Example 1 was performed, except that the nucleating agent was added in the type and amount shown in (1). The results are shown in Tables 1 and 2.

Example 6 The amount of butyl acetate used in the second stage of the main polymerization in Example 1 was 0.14 mmol, and 1,3-bis (t-
The same operation as in Example 1 was performed, except that butyl peroxyisopropyl) benzene was used in an amount of 0.04% by weight and the nucleating agents were added in the types and amounts shown in Table 2. Tables 1 and 2 show the results.
It was shown to.

Example 7 In the main polymerization of Example 1, diethyl aluminum (2,6-
The same operation as in Example 1 was carried out except for using di-t-butylphenoxide) and adding the nucleating agent in the kind and amount shown in Table 2. The results are shown in Tables 1 and 2.

Example 8 In the main polymerization of Example 1, the polymerization time of the first stage was 90
, And the same operation as in Example 1 was performed except that 0.02% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used during granulation. The results are shown in Tables 1 and 2.

Example 9 In the main polymerization of Example 1, the first stage polymerization was carried out at a hydrogen concentration of 0.2 mol%, and the second stage polymerization was carried out at a hydrogen concentration of 5 m
ol%, and the same operation as in Example 1 was performed, except that the nucleating agent was added in the type and amount shown in Table 2. The results are shown in Tables 1 and 2.

Example 10 Instead of propylene in the prepolymerization of Example 1, 3
-Methyl-1-butene was introduced at a rate of 2 g per 1 g of titanium trichloride, and 0.05% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used at the time of granulation. The same operation as in Example 1 was performed except that the nucleating agent was not added. The results are shown in Tables 1 and 2.

Example 11 Instead of propylene in the prepolymerization of Example 1, 3
-Methyl-1-butene was introduced in an amount of 1 g per 1 g of titanium trichloride, and 0.05% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used during granulation. The same operation as in Example 1 was performed except that the nucleating agent was added in different types and amounts. The results are shown in Tables 1 and 2.

Example 12 In the prepolymerization of Example 1, instead of propylene, vinylcyclohexene was added in an amount of 0.15 g / g of titanium trichloride.
g in Example 1, except that 0.05% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used during granulation, and no nucleating agent was added during granulation. The same operation as in Example 1 was performed. The results are shown in Tables 1 and 2.

Comparative Example 1 The same operation as in Example 1 was performed, except that no nucleating agent was used. The results are shown in Tables 1 and 2.

Comparative Examples 2 to 4 In Example 2, no nucleating agent was used (Comparative Example 2). In Example 3, no nucleating agent was used (Comparative Example 3). At the time of graining, 0.25 wt. The same operation as in Examples 2 and 3 was performed except for using% (Comparative Example 4). Table 1 shows the results.
2 is shown.

Comparative Examples 5 and 6 In Example 8, no nucleating agent was used (Comparative Example 5), and in Example 9, no nucleating agent was used (Comparative Example 6). The same operation as in No. 9 was performed.
The results are shown in Tables 1 and 2.

Comparative Example 7 The amount of butyl acetate used in the main polymerization of Example 1 was 0.0
The same operation as in Example 1 was carried out, except that the nucleating agent was added in the amount and type shown in Table 2 during granulation. The results are shown in Tables 1 and 2.

Comparative Example 8 In the main polymerization of Example 1, the polymerization time in the first stage was 1 hour, the amount of butyl acetate used was 0.007 mmol, and 1,3-bis (t-butylperoxy The same operation as in Example 1 was performed except that 0.04% by weight of (isopropyl) benzene was used, and the nucleating agents were added in the types and amounts shown in Table 2. The results are shown in Tables 1 and 2.

Comparative Example 9 In the main polymerization of Example 1, 0.014 mmol of butyl acetate was used in the first stage polymerization, and 1,3-bis (t-butylperoxyisopropyl) benzene was used in an amount of 0.06 mmol during granulation. The same operation as in Example 1 was performed except that the weight% was used. The results are shown in Tables 1 and 2.

Comparative Example 10 In the main polymerization of Example 1, 0.014 mmol of butyl acetate was used in the first stage polymerization, and 0.05 g of 1,3-bis (t-butylperoxyisopropyl) benzene was used in the granulation. Wt% and no nucleating agent was used,
The same operation as in Example 1 was performed. The results are shown in Tables 1 and 2.

Comparative Example 11 In the main polymerization of Example 1, no ethyl aluminum sesquiethoxide was used, the polymerization time in the first stage was 30 minutes, and the amount of butyl acetate used in the second stage was 0.14 mm.
, and 0.05% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used during granulation.
The same operation as in Example 1 was performed, except that the nucleating agent was added in the type and amount shown in (1). The results are shown in Tables 1 and 2.

Comparative Example 12 In the main polymerization of Example 1, no ethylaluminum sesquiethoxide was used, the polymerization time in the first step was 30 minutes, and the amount of butyl acetate used in the second step was 0.14 mm.
ol, and the same operation as in Example 1 was performed except that 0.05% by weight of 1,3-bis (t-butylperoxyisopropyl) benzene was used during granulation and no crystal nucleating agent was used. The results are shown in Tables 1 and 2.

[0096]

[Table 1]

[0097]

[Table 2]

[Brief description of the drawings]

FIG. 1 is an elution curve of a low-temperature polypropylene elution fractionation method of low-crystalline polypropylene of Example 1.

Claims (2)

[Claims] 1. A propylene homopolymer or a copolymer of propylene and an α-olefin having a content of α-olefin other than propylene of 5 mol% or less, wherein (1) a melt flow rate is 1 to 20 g / 10 minutes, (2) In the elution curve represented by the elution temperature (° C.) on the abscissa and the integrated weight ratio of the eluted components on the ordinate,
The amount of the eluted component (component A) at a temperature lower than 20 ° C is 5 to 35% by weight, and the amount of the eluted component (B component) at 100 ° C or higher is 40 to 80%.
% By weight, based on 100 parts by weight of low-crystalline polypropylene, 0.01 to 1 part by weight of an organic crystal nucleating agent, and / or
Alternatively, a low-crystalline polypropylene resin composition comprising a polymer crystal nucleating agent in a ratio of 1 to 1000 ppm by weight. 2. The low crystalline polypropylene resin composition according to claim 1, wherein the component B has a peak top temperature of 120 ° C. or higher.