JPH083009B2 - Highly rigid propylene homopolymer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a high-rigidity propylene homopolymer composition. More specifically, it relates to a high-rigidity propylene homopolymer composition capable of obtaining a molded article having extremely excellent rigidity and heat resistance.

[Prior art] Generally, propylene-based polymers have excellent processability, chemical resistance, electrical properties and mechanical properties, and are processed into injection molded articles, hollow molded articles, films, sheets, fibers, etc. Used for applications. However, these properties may not be sufficient depending on various specific uses, and there is a problem that expansion of the specific uses is limited. Particularly, in terms of rigidity and rigidity such as heat resistance, they are inferior to polyesters such as polystyrene, ABS resin, polyethylene terephthalate and polybutylene terephthalate, and thus become a serious bottleneck in expanding applications of propylene polymers. Therefore, if it is possible to improve the rigidity (which means rigidity and heat resistance rigidity), it is possible to reduce the thickness of the molded product by that amount, which not only contributes to resource saving, but also increases the cooling rate during molding. Therefore, the molding speed per unit time can be increased, which can contribute to the improvement of productivity.

Therefore, conventionally, various nucleating agents have been used alone or in combination for the purpose of improving the rigidity of the propylene-based polymer. On the other hand, JP-A-58-104905, JP-A-58-104906, and JP-A-58-104905 related to the application of the same applicant as the present application
58-104907 and JP-A-59-22913 disclose crystalline propylene homopolymers having a specific isotactic pentad fraction. In addition, in each of the above publications, an organic nucleating agent such as pt-butyl aluminum benzoate or 1,3,2,4-dibenzylidene sorbitol is added to the crystalline propylene homopolymer for the purpose of further improving the rigidity. Is disclosed.

[Problems to be Solved by the Invention] However, a propylene-based polymer composition prepared by blending various conventionally known nucleating agents with an ordinary propylene-based polymer is one in which the effect of improving the rigidity is still sufficiently satisfied. is not. JP-A-58-104905, JP-A-58-104906
JP-A-58-104907 and JP-A-59-2291.
The crystalline propylene homopolymers having the specific isotactic pentad fractions disclosed in each of the publications of JP-A No. 3 (1998) are considerably satisfactory in terms of rigidity without blending with a nucleating agent, but still satisfactory. is not. Further, an organic nucleating agent such as pt-butyl aluminum benzoate or 1,3,2,4-dibenzylidene sorbitol is added to the crystalline propylene homopolymer having the specific isotactic pentad fraction described above. Although the propylene homopolymer composition thus obtained has a considerable effect of improving the rigidity, it is still not sufficiently satisfactory when it is used in applications requiring a high rigidity.

The present inventor has conducted extensive studies in order to solve the above-mentioned problems with respect to the propylene-based polymer composition containing the various nucleating agents, that is, the problems of rigidity and heat-resistant rigidity. As a result, a composition obtained by blending a crystalline propylene homopolymer having a specific isotactic pentad fraction with a phosphate compound represented by the following general formula [I] (hereinafter referred to as compound A). It was found that the above problems of the propylene-based polymer composition can be solved, and the present invention was completed based on this finding.

(In the formula, R represents hydrogen or an alkyl group having 1 to 18 carbon atoms, an alkoxy group, a cycloalkyl group, a phenyl group or a phenoxy group.) As is clear from the above description, the object of the present invention is to provide rigidity and heat resistance. It is an object of the present invention to provide a propylene homopolymer composition capable of obtaining a molded article having extremely excellent rigidity.

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

The relationship between the isotactic pentad fraction (P) and the melt flow rate (MFR; discharge amount of molten resin for 10 minutes when a load of 2.16 kg at 230 ° C. is applied) is 1.00 ≧ P ≧ 0.
015 log MFR + 0.955, and the isotactic pentad fraction (P) of the extract sequentially extracted with boiling n-hexane and boiling n-heptane was 0.450 to 0.700 and 0.
With respect to 100 parts by weight of a crystalline propylene homopolymer of 750 to 0.930 (excluding the crystalline propylene homopolymer shown below), a phosphate compound represented by the following general formula [I] (hereinafter, Compound A)
A high-rigidity propylene homopolymer composition containing 0.01 to 1 part by weight.

When polymerizing propylene in multiple stages, 35 to 65 wt% of the total amount of polymer is polymerized in the first stage, and 65 to 35 wt% is polymerized in the second stage and thereafter. Of the polymer parts produced in the second and subsequent stages, the intrinsic viscosity of the polymer part having a high molecular weight is [η] _H , and the intrinsic viscosity of the polymer part having a low molecular weight is [η].
_{When L} , 3.0 ≦ [η] _H − [η] _L ≦ 6.5 (1) A crystalline propylene homopolymer having the intrinsic viscosity value of each polymer part.

(In the formula, R represents hydrogen or an alkyl group having 1 to 18 carbon atoms, an alkoxy group, a cycloalkyl group, a phenyl group or a phenoxy group.) The crystalline propylene homopolymer used in the present invention is an isotactic pentad component. The relationship between the rate (P) and the melt flow rate (MFR) satisfies 1.00 ≧ P ≧ 0.015 logMFR + 0.955, and the isotacticity of the extract sequentially extracted with boiling n-hexane and boiling n-heptane The pentad fraction (P) is 0.450-0.700 and 0.
It is a crystalline propylene homopolymer of 750 to 0.930.
Such a crystalline propylene homopolymer can be produced by the production method described in JP-A-58-104907 related to the application of the same applicant as the present application. That is, an organoaluminum compound (I) (eg, triethylaluminum, diethylaluminum monochloride, etc.) or a reaction product (V) of an organoaluminum compound (I) with an electron donor (eg, diisoamyl ether, ethylene glycol monomethyl ether, etc.) Solid product (II) obtained by reacting benzene with titanium tetrachloride and further with an electron donor and an electron acceptor (eg anhydrous aluminum chloride, titanium tetrachloride, vanadium tetrachloride) Compound (III) in combination with organoaluminum compound (I) and aromatic carboxylic acid ester (IV) (eg ethyl benzoate, methyl p-toluate, ethyl p-toluate, 2-ethylhexyl p-toluate, etc.) , The aromatic carboxylic acid ester (IV) and the solid formation Propylene in the presence of a catalyst and the molar ratio IV / III = 0.1 to 10.0 of (III) can be obtained by polymerizing in one or more stages. One step in this case means one section of continuous or temporary supply of these monomers. Here, the isotactic pentad fraction (P) refers to Macromolecules, Volume 6, No. 6, November to December, pages 925 to 926 (1973) [Macromolecules, Vol.
6, No6, November-December, 925-926 (1973)], that is, an isotactic pen at the pentad unit in the propylene-based polymer molecular chain measured using ¹³ C-NMR. It is the tad fraction. In other words, the fraction means the fraction of propylene monomer units in which five propylene monomer units are continuously isotactically bonded. The determination of the attribution of the peak of the spectrum in the measurement using ¹³ C-NMR described above is carried out by Macromolecules,
Volume 8, Issue 5, September-October, pages 687-689 (1975) [Macr
omolecules, Vol.8, No5, September-October, 687-689
(1975)]. By the way, the measurement by ¹³ C-NMR in the examples described later was performed by using an FT-NMR device of 270 MHz and by integrating measurement of 27,000 times, the signal detection limit was improved to 0.001 in isotactic pentad fraction. It was The requirement of the relational expression between the isotactic pentad fraction (P) and the melt flow rate (MFR) is that the fraction P of a propylene homopolymer having a low MFR generally decreases, so that the propylene homopolymer weight to be used should be reduced. As a unity, the constitutional requirement is to limit the lower limit value of P corresponding to the MFR. Since P is a fraction, 1.00 is the upper limit. Next, the boiling n-hexane extract is usually contained in the propylene homopolymer in an amount of several%, but the fraction of this extract can vary greatly depending on the propylene polymerization method, such as 0.10 to 0.70. The crystalline propylene homopolymer used in the present invention has this boiling n
-The fraction P of the hexane extract must be in the range 0.450 to 0.700. A composition using a homopolymer having a P of less than 0.450 in the extract improves the rigidity but does not sufficiently improve the heat resistance rigidity. Similarly, the fraction P of the extract, which was subsequently extracted with boiling n-heptane, was determined by adding a further boiling n for the residue extracted with boiling n-hexane as described above.
-Isotactic pentad fraction of the extract extracted with heptane. The crystalline propylene homopolymer used in the present invention has a boiling n-heptane extract having a P of 0.750 to
It must be within the range of 0.930. A composition using a homopolymer of less than 0.750 improves the rigidity, but the improvement in heat resistance rigidity is still insufficient. Boiling n-
The total extraction amount of the sequential extract with hexane and boiling n-heptane is not limited, but the total amount in the starting crystalline propylene homopolymer is practically in the range of 1.0 to 10.0% by weight. Crystalline propylene homopolymers within the range give more preferable results than those outside the range. The above-mentioned sequential extraction is performed as follows. That is, a granulated product obtained by mixing a powdery crystalline propylene homopolymer with a small amount of an antioxidant (for example, 0.1% by weight of 2,6-di-t-butyl-p-cresol) and granulating with an extruder. Was pulverized using a pulverizer, the pulverized product was sieved with 20 mesh (Tyler), and 3 g of the 20 mesh passed portion was first extracted with 100 ml of boiling n-hexane using a Soxhlet extractor, followed by 100 ml.
It is released with boiling n-heptane for 6 hours each, and a poor solvent such as methanol, anhydrous ethanol or acetone is added to each extract to precipitate a soluble substance, and the precipitate is separated, dried and weighed. In addition, MFR complies with JIS K 7210, 230
Measure at ℃ and load 2.16kg.

Further, in the crystalline propylene homopolymer used in the present invention, the crystalline propylene homopolymer has a crystalline propylene homopolymer having an isotactic pentad fraction outside the scope of the present invention, and a propylene component. Crystalline random of propylene containing 70% by weight or more and one or more α-olefins such as ethylene, butene-1, pentene-1, 4-methyl-pentene-1, hexene-1, octene-1 Copolymer or crystalline block copolymer, copolymer of propylene and vinyl acetate or acrylic acid ester, or saponified product of the copolymer,
A copolymer of propylene and an unsaturated silane compound, a copolymer of propylene and an unsaturated carboxylic acid or an anhydride thereof, a reaction product of the copolymer and a metal ion compound, or a crystalline propylene-based polymer. It is also possible to use a modified propylene polymer modified with an unsaturated carboxylic acid or a derivative thereof, or a mixture of a silane-modified propylene polymer modified with a crystalline propylene polymer with an unsaturated silane compound, or the like. Various synthetic rubbers (for example, ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene copolymer rubber, polybutadiene, polyisoprene, polychloroprene, chlorinated polyethylene, chlorinated polypropylene, styrene-butadiene rubber, acrylonitrile-butadiene) System rubber, styrene-butadiene- Tylene block copolymer, styrene-iprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-propylene-butylene-styrene block copolymer, etc. or thermoplastic synthetic resin (for example, ultra low Density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene,
Ultra-high molecular weight polyethylene, polybutene, polyolefins other than propylene-based polymers such as poly-4-methylpentene-1, polystyrene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, polyamide, polyethylene terephthalate, polybrene terephthalate , Polycarbonate, polyvinyl chloride, fluororesin, etc.) can also be mixed and used. At this time, the mixture is 1.00 ≧ P ≧ 0.015l
ogMFR + 0.955 was satisfied, and P of the extract successively extracted with boiling n-hexane and boiling n-heptane was 0.
Anything satisfying 450 to 0.700 and 0.750 to 0.930 may be used.

Examples of the compound A used in the present invention include aluminum hydroxy-di-phenyl phosphate, aluminum hydroxy-bis (p-methylphenyl) phosphate, aluminum hydroxy-bis (p-ethylphenyl) phosphate, aluminum hydroxy. -Bis (pn-propylphenyl) phosphate,
Aluminum hydroxy-bis (pi-propylphenyl) phosphate, aluminum hydroxy-
Bis (pn-butylphenyl) phosphate, aluminum hydroxy-bis (pi-butylphenyl) phosphate, aluminum hydroxy-bis (ps-butylphenyl) phosphate, aluminum hydroxy-bis ( pt-butylphenyl) phosphate, aluminum hydroxy-bis (p-
n-amylphenyl) phosphate, aluminum hydroxy-bis (pi-amylphenyl) phosphate, aluminum hydroxy-bis (ps-amylphenyl) phosphate, aluminum hydroxy-bis (pt- Amylphenyl) phosphate, aluminum hydroxy-bis (p-hexylphenyl) phosphate, aluminum hydroxy-
Bis (pn-octylphenyl) phosphate, aluminum hydroxy-bis (p-2-ethylhexylphenyl) phosphate, aluminum hydroxy-bis (pt-octylphenyl) phosphate, aluminum hydroxy-bis ( p-nonylphenyl) phosphate, aluminum hydroxy-bis (p-dodecylphenyl) phosphate, aluminum hydroxy-bis (p-tridecylphenyl) phosphate, aluminum hydroxy-bis (p-
Hexadecylphenyl) phosphate, aluminum hydroxy-bis (p-octadecylphenyl) phosphate, aluminum hydroxy-bis (p-methoxyphenyl) phosphate, aluminum hydroxy-bis (p-ethoxyphenyl) phosphate, aluminum Hydroxy-bis (p-propoxyphenyl) phosphate, aluminum hydroxy-bis (p-butoxyphenyl) phosphate, aluminum hydroxy-bis (p-octoxyphenyl) phosphate, aluminum hydroxy-bis (p- Cyclohexylphenyl) phosphate, aluminum hydroxy-bis (p-biphenylyl) phosphate and aluminum hydroxy-bis (p
-Phenoxyphenyl) phosphate and the like, and aluminum hydroxy-bis (pt-butylphenyl) phosphate is particularly preferred. These phosphate compounds can be used alone or in combination of two or more. The mixing ratio of the compound A is 0.01 to 1 part by weight, preferably 0.0 to 100 parts by weight of the above-mentioned crystalline propylene homopolymer.
5 to 0.5 parts by weight. If the amount is less than 0.01 part by weight, the effect of improving rigidity and heat resistance is not sufficiently exhibited, and the amount may be more than 1 part by weight. Uneconomical and uneconomical.

In the composition of the present invention, various additives usually added to propylene-based polymers such as phenol-based, thioether-based, phosphorus-based antioxidants, light stabilizers, clarifying agents, nucleating agents, Lubricants, antistatic agents, anti-fog agents, anti-blocking agents, anti-drop agents, pigments, heavy metal deactivators (copper damage inhibitors), radical generators such as peroxides, dispersants such as metal soaps or medium Additives, inorganic fillers (eg talc, mica, clay, wollastonite, zeolite,
Asbestos, calcium carbonate, aluminum hydroxide, magnesium hydroxide, silicon dioxide, titanium dioxide, zinc oxide, magnesium oxide, zinc sulfide, barium sulfate, calcium silicate, aluminum silicate, glass fiber, potassium titanate, carbon fiber, carbon The inorganic filler or organic filler surface-treated with a surface treatment agent such as black, graphite, metal fiber) or a coupling agent (eg, silane-based, titanate-based, boron-based, aluminate-based, zircoaluminate-based) Agents (for example, wood flour, pulp, waste paper, synthetic fibers, natural fibers, etc.) can be used in combination as long as the object of the present invention is not impaired.
In particular, when an inorganic filler is used in combination, the rigidity and heat-resistant rigidity are further improved.

The composition of the present invention is prepared by adding a predetermined amount of the compound A and the various additives usually added to the propylene-based polymer to the above-mentioned crystalline propylene homopolymer according to the present invention in a conventional mixing device such as Henschel. Mixer (trade name),
Mix using a super mixer, ribbon blender, Banbury mixer, etc., and use a normal single-screw extruder, twin-screw extruder, Brabender or roll to melt and knead temperature 17
It can be obtained by melt-kneading and pelletizing at 0 ° C to 300 ° C, preferably 200 ° C to 250 ° C. The obtained composition is used for production of a target molded article by various molding methods such as an injection molding method, an extrusion molding method, and a blow molding method.

[Action] In the present invention, the phosphate compound represented by Compound A is disclosed in JP-B-41-16303 and JP-A-53-10555.
It is generally known that it acts as a nucleating agent to improve the rigidity and the heat resistance rigidity like the phosphate compound disclosed in Japanese Patent Laid-Open Publication No. However, the aforementioned Japanese Patent Publication No. 41-
Compound A, which is a monobasic aluminum salt of a phosphate compound (aluminum normal salt) disclosed in Japanese Patent No. 16303 and Japanese Patent Application Laid-Open No. 53-105550, has a specific isotactic pentad fraction according to the present invention. By blending with a crystalline propylene homopolymer having a, a surprising synergistic effect that cannot be predicted from the blending of a conventionally known nucleating agent is exhibited, and a composition having extremely excellent rigidity and heat resistance can be obtained. I found it.

[Effects of the Invention] The composition of the present invention is significantly superior in (1) rigidity and heat resistance as compared with a conventionally known propylene homopolymer composition containing various nucleating agents. (2) Not only can it contribute to resource saving by reducing the thickness of the molded product, but also because the cooling rate during molding is faster, the molding rate per unit time can be increased, which also contributes to improved productivity. it can. (3) Polypropylene resin can be used in applications where polyesters such as polystyrene, ABS resin, polyethylene terephthalate and polybutylene terephthalate have been conventionally used, and the applications of polypropylene resin can be expanded.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to Examples, Comparative Examples, and Production Examples, but the present invention is not limited thereto.

The evaluation methods used in Examples and Comparative Examples were as follows.

1) Rigidity: length 100mm, width 10m using the obtained pellets
A test piece having a thickness of 4 mm and a thickness of 4 mm was prepared by an injection molding method, and the rigidity was evaluated by measuring the flexural modulus (based on JIS K 7203) using the test piece. A material having a high rigidity means a material having a large flexural modulus.

2) Heat-resistant stiffness: 130 mm long using the obtained pellets
A test piece having a width of 13 mm and a thickness of 6.5 mm was prepared by an injection molding method, and the heat distortion temperature was measured using the test piece (JIS K 72
According to 07; 4.6 kgf / cm ² load), the heat resistance rigidity was evaluated. A material having high heat resistance and rigidity means a material having a high heat distortion temperature.

Production Examples 1 to 3 (Production Method of Crystalline Propylene Homopolymer Used in Examples and Comparative Examples) (1) Preparation of Catalyst n-Hexane 600 ml, diethyl aluminum monochloride (DEAC) 0.50 mol, diisoamyl ether 1.20 mol Mix at 25 ° C for 1 minute and react at the same temperature for 5 minutes to produce reaction product liquid (V) (diisoamyl ether / DEAC molar ratio 2.
4) got. 4.0 mol of titanium tetrachloride was placed in a reactor purged with nitrogen, heated to 35 ° C., and the whole amount of the above reaction product liquid (V) was added dropwise thereto for 180 minutes, and then kept at the same temperature for 30 minutes.
The temperature was raised to 5 ° C and the reaction was continued for another 1 hour, the mixture was cooled to room temperature (20 ° C), the supernatant was removed, 4000 ml of n-hexane was added, and the operation of removing the supernatant by decantation was repeated 4 times.
190 g of solid product (II) was obtained. The total amount of this solid organism (II) was suspended in 3000 ml of n-hexane at 20 ° C.
Then, 160 g of diisoamyl ether and 350 g of titanium tetrachloride were added at room temperature for about 1 minute and reacted at 65 ° C. for 1 hour. After completion of the reaction, the mixture was cooled to room temperature, the supernatant was removed by deanthation, 4000 ml of n-hexane was added, the mixture was stirred for 10 minutes, allowed to stand, and the procedure of removing the supernatant was repeated 5 times. It was dried under reduced pressure to obtain a solid organism (III).

(2) Preparation of pre-activated catalyst After replacing a stainless reactor with an inclined blade with an internal volume of 20 with nitrogen gas, n-hexane 15, 42 g of diethylaluminum monochloride and 30 g of solid product (III) were added at room temperature. After that, put 15Nl of hydrogen and propylene partial pressure 5kg /
The reaction was carried out at cm ² G for 5 minutes, unreacted propylene, hydrogen and n-hexane were removed under reduced pressure to obtain the pre-activated catalyst (VI) in the form of powder (solid product (III) 1 g of propylene 82.
0g reaction).

(3) Polymerization of Propylene Dry n-hexane 10 in a stainless steel polymerization vessel equipped with a turbine type stirring blade and having an internal volume of 250, which was replaced with nitrogen gas.
Then 10 g of diethylaluminium monochloride, 10 g of the preactivated catalyst (VI) and 1 of methyl p-toluate 1
1.0 g was charged, and hydrogen was further added in 100 Nl in Production Example 1, 200 Nl in Production Example 2 and 410 Nl in Production Example 3. Then, after the temperature inside the vessel was raised to 70 ° C., propylene was supplied into the vessel and the pressure inside the vessel was increased to 10 kg / cm ² G. Then, the polymerization was continued for 4 hours while maintaining the temperature at 70 ° C and the pressure at 10 kg / cm ² G, 25 methanol was supplied, and the temperature was raised to 80 ° C. After 30 minutes, 100 g of a 20% by weight aqueous sodium hydroxide solution was added, and the mixture was stirred for 20 minutes, pure water 50 was added, and then residual propylene was discharged. After extracting the water layer, 50 more pure water was added and washed with stirring water for 10 minutes, the water layer was extracted, the crystalline propylene homopolymer-n-hexane slurry was extracted, the slurry was filtered, and the filtered material was dried. Thus, a white crystalline propylene homopolymer powder was obtained.
The obtained polymer was used for determining the above-mentioned melt flow rate (MFR) and each isotactic pentad fraction (P). The results of these analyzes are shown in Table 1.

Production Example 4 (Production Example of Crystalline Propylene Homopolymer Used in Comparative Example) n-Hexane 10 dried in a stainless steel polymerization vessel equipped with a turbine type stirring blade and having an inner volume of 250, which was replaced with nitrogen gas.
0 Then, 10 g of diethylaluminum monochloride, 40 g of a commercially available catalyst (AA type) in which titanium tetrachloride was reduced and activated by metal aluminum and 22.0 g of methyl p-toluate were used.
Was charged, and 200 Nl of hydrogen was further added. Then, after the temperature inside the vessel was raised to 70 ° C., propylene was supplied into the vessel and the pressure inside the vessel was increased to 10 kg / cm ² . Then, the polymerization was continued for 4 hours while maintaining the temperature at 70 ° C and the pressure at 10 kg / cm ² G, 25 methanol was supplied, and the temperature was raised to 80 ° C. After 30 minutes, 100 g of a 20% by weight aqueous sodium hydroxide solution was added, and the mixture was stirred for 20 minutes, pure water 50 was added, and then residual propylene was discharged. After extracting the water layer, 50 more pure water was added and washed with stirring water for 10 minutes, the water layer was extracted, the crystalline propylene homopolymer-n-hexane slurry was extracted, the slurry was filtered, and the filtered material was dried. Thus, a white crystalline propylene homopolymer powder was obtained. The obtained polymer was used for determining the above-mentioned melt flow rate (MFR) and each isotactic pentad fraction (P).
The results of these analyzes are shown in Table 1.

Examples 1 to 3, Comparative Examples 1 to 12 Powder form having each melt flow rate (MFR) and each isotactic pentad fraction (P) produced in Production Examples 1 to 3 shown in Table 2 below. To 100 parts by weight of the crystalline propylene homopolymer, a predetermined amount of aluminum hydroxy-bis (pt-butylphenyl) phosphate as the compound A and other additives were added at the blending ratios shown in Table 2 below. Put in a Henschel mixer (trade name), stir and mix for 3 minutes, then use a single screw extruder with a diameter of 40 mm.
The mixture was melt-kneaded at 200 ° C. and pelletized. Further, as powdery crystalline propylene alone having each melt flow rate (MFR) and each isotactic pentad fraction (P) produced in Production Examples 1 to 4 shown in Table 2 below as Comparative Examples 1 to 12 A predetermined amount of each of the additives shown in Table 2 below was added to 100 parts by weight of the polymer, and the mixture was melt-kneaded in accordance with Examples 1 to 3 to obtain pellets.

Test pieces used for the rigidity and heat resistance rigidity tests were prepared by injection molding the obtained pellets at a resin temperature of 250 ° C and a mold temperature of 50 ° C.

Using the obtained test piece, the rigidity and the heat resistance rigidity were evaluated by the above-mentioned test methods. The results are shown in Table 2.

Examples 4 to 6 and Comparative Examples 13 to 24 Powder form having each melt flow rate (MFR) and each isotactic pentad fraction (P) produced in Production Examples 1 to 3 shown in Table 3 below. To 100 parts by weight of the crystalline propylene homopolymer, aluminum hydroxy-bis (pt-butylphenyl) phosphate as the compound A, fine particle talc having an average particle size of 2 to 3 μm as the inorganic filler, and other additives, respectively. Put a predetermined amount into the Henschel mixer (trade name) at the blending ratio shown in Table 3 below, stir and mix for 3 minutes, then use a single screw extruder with a diameter of 40 mm.
The mixture was melt-kneaded at 200 ° C. and pelletized. Also, powdery crystalline propylene alone having each melt flow rate (MFR) and each isotactic pentad fraction (P) produced in Production Examples 1 to 4 shown in Table 3 below as Comparative Examples 13 to 24. A predetermined amount of each of the additives shown in Table 3 below was added to 100 parts by weight of the polymer, and the mixture was melt-kneaded in accordance with Examples 4 to 6 to obtain pellets.

Test pieces used for the rigidity and heat resistance rigidity tests were prepared by injection molding the obtained pellets at a resin temperature of 250 ° C and a mold temperature of 50 ° C.

Using the obtained test piece, the rigidity and the heat resistance rigidity were evaluated by the above-mentioned test methods. The results are shown in Table 3.

The compounds and additives according to the present invention shown in Tables 2 and 3 are as follows.

Compound A: Aluminum hydroxy-bis (pt-butylphenyl) phosphate Nucleating agent 1: p-t-Butyl aluminum benzoate Nucleating agent 2: 1,3,2,4-dibenzylidene sorbitol Nucleating agent 3: Sodium-bis (pt-butylphenyl)
Phosphate [manufactured by Adeka Argus Chemical Co., Ltd .; MARK
NA-10UF] Nucleating agent 4: Aluminum-bis (pt-butylphenyl) phosphate Nucleating agent 5: Aluminum-2,2'-methylene-bis (4,6-
Di-t-butylphenyl) phosphate nucleating agent 6: aluminiumhydroxy-2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate phenolic antioxidant 1: 2, 6-di-t-butyl-p-
Cresol phenolic antioxidant 2: tetrakis [methylene-3-
(3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methanephosphorus antioxidant 1: tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene- Di-phosphonite Phosphorus antioxidant 2: Bis (2,4-di-t-butylphenyl) -pentaerythritol-diphosphite Ca-St: Calcium stearate Inorganic filler: Talc (average particle size 2-3μ ) The examples and comparative examples described in Table 2 are the cases where a crystalline propylene homopolymer having each melt flow rate and each isotactic pentad fraction was used as the propylene-based polymer. As can be seen from Table 2, Examples 1 to 3 are obtained by compounding Compound A with a crystalline propylene homopolymer having an isotactic pentad fraction within the scope of the present invention. 3 and Comparative Example 1
3 to 3 (a crystalline propylene homopolymer having an isotactic pentad fraction outside the scope of the present invention, compounded with an organic nucleating agent consisting of compound A or a compound other than compound A). As a result, Examples 1 to 3 have excellent rigidity and heat resistance. Further, comparing Comparative Examples 4 to 6 and Examples 1 to 3 in which the organic nucleating agent is not blended with the crystalline propylene homopolymer having the isotactic pentad fraction within the scope of the present invention,
Comparative Examples 4 to 6 are still insufficient in the effect of improving the rigidity and the heat resistance rigidity. Further, Comparative Examples 7 to 12 and Examples 1 to 3 in which an organic nucleating agent composed of a compound other than the compound A was blended with a crystalline propylene homopolymer having an isotactic pentad fraction within the scope of the present invention. Comparison example 7
Although the effect of improving rigidity and heat resistance is considerably recognized, the results of Examples 1 to 12 are still not sufficient, and the rigidity and heat resistance of Examples 1 to 3 are remarkably excellent, and by adding the compound A, a remarkable synergistic effect is recognized. I understand. In particular, it is clear that Comparative Example 10 containing the aluminum normal salt of the compound A (monobasic aluminum salt) according to the present invention does not exhibit the effects of the present invention, which is described in Japanese Patent Publication No. 41-16303. JP-A-53-105550
Nothing is described in the official gazette. That is, the rigidity and the heat resistance obtained by the present invention are unique to the first time when the compound A is blended with the crystalline propylene homopolymer having the isotactic pentad fraction within the range limited in the present invention. Can be said to be the effect of.

Table 3 shows that the propylene polymer used in Table 2 was used in combination with talc as an inorganic filler, and the same effect as described above was confirmed for this.

From this, it can be seen that the composition of the present invention is remarkably excellent in rigidity and heat resistance as compared with the composition obtained by blending a nucleating agent with a conventionally known crystalline propylene homopolymer. The remarkable effect of the composition of the present invention was confirmed.

Claims (5)

[Claims] 1. The relationship between the isotactic pentad fraction (P) and the melt flow rate (MFR; discharge amount of molten resin for 10 minutes when a load of 2.16 kg at 230 ° C. is applied) is 1.
00 ≧ P ≧ 0.015 log MFR + 0.955, and the isotactic pentad fraction (P) of the extract sequentially extracted with boiling n-hexane and boiling n-heptane is 0.450 to 0.7, respectively.
00 and 0.750 to 0.930 of crystalline propylene homopolymer (excluding crystalline propylene homopolymer shown below) to 100 parts by weight of the phosphate compound represented by the following general formula [I] ( Hereinafter, a high-rigidity propylene homopolymer composition containing 0.01 to 1 part by weight of Compound A). When polymerizing propylene in multiple stages, 35 to 65 wt% of the total amount of polymer is polymerized in the first stage, and 65 to 35 wt% is polymerized in the second stage and thereafter. Of the polymer parts produced in the second and subsequent stages, the intrinsic viscosity of the polymer part having a high molecular weight is [η] _H , and the intrinsic viscosity of the polymer part having a low molecular weight is [η].
_{When L} , 3.0 ≦ [η] _H − [η] _L ≦ 6.5 (1) A crystalline propylene homopolymer having the intrinsic viscosity value of each polymer part. (In the formula, R represents hydrogen or an alkyl group having 1 to 18 carbon atoms, an alkoxy group, a cycloalkyl group, a phenyl group or a phenoxy group.) 2. In the general formula [I], R has 1 to 9 carbon atoms.
The high-rigidity propylene homopolymer composition according to claim (1), which is an alkyl group of 3. A high-rigidity propylene homopolymer composition according to claim 1, wherein aluminum hydroxy-bis (pt-butylphenyl) phosphate is compounded as the compound A. 4. A high-rigidity propylene homopolymer composition according to claim (1), which comprises an inorganic filler. 5. As an inorganic filler, talc, mica, clay, wollastonite, zeolite, asbestos, calcium carbonate, aluminum hydroxide, magnesium hydroxide, silicon dioxide, titanium dioxide, zinc oxide, magnesium oxide, zinc sulfide, sulfuric acid. Use of one or more selected from barium, calcium silicate, aluminum silicate, glass fiber, potassium titanate, carbon fiber, carbon black, graphite and metal fiber. Claim (4). The high-rigidity propylene homopolymer composition described in 1.