JPH0515739B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a highly rigid propylene homopolymer composition. More specifically, the present invention relates to a highly rigid propylene homopolymer composition that has excellent rigidity and heat-resistant rigidity. [Prior art] Propylene polymers generally have excellent processability, chemical resistance, electrical properties, and mechanical properties, so they are processed into injection molded products, blow molded products, films, sheets, fibers, etc. It is used for a purpose. However, depending on various specific applications,
These properties may not be sufficient in some cases, and there is a problem in that the expansion of their specific uses is limited. In particular, in terms of rigidity such as rigidity and heat resistance, it is inferior to polystyrene, ABS resin, polyester, etc., and this has become a serious bottleneck in expanding the use of propylene polymers.
In addition, if it is possible to improve the rigidity, the molded product can be made thinner, which not only contributes to resource conservation, but also increases the cooling rate during molding, increasing the molding speed per unit time. This can contribute to improving productivity. For this reason, various nucleating agents have been used singly or in combination for the purpose of improving the rigidity of propylene polymers. On the other hand, Japanese Patent Application Laid-Open No. 58-104905, filed by the same applicant as the present application,
Propylene homopolymers having a specific isotactic pentad fraction are disclosed in JP-A No. 58-104906, JP-A-58-104907, and JP-A-59-22913. Further, in each of the above-mentioned publications, an organic nucleating agent consisting of aluminum pt-butylbenzoate or 1,2,3,4-dibenzylidene sorbitol is added to the propylene homopolymer for the purpose of further improving the rigidity. is disclosed. [Problems to be Solved by the Invention] However, propylene polymer compositions prepared by blending various conventionally known nucleating agents with ordinary propylene polymers still have a sufficiently satisfactory improvement effect in terms of rigidity. isn't it. Also, the above-mentioned Unexamined Patent Application Publication No. 1987-
Publication No. 104905, Japanese Unexamined Patent Publication No. 104906, Japanese Unexamined Patent Publication No. 1983-104906
Although the propylene homopolymers having specific isotactic pentad fractions disclosed in JP-A-58-104907 and JP-A-59-22913 are considerably improved in terms of rigidity, they are still not fully satisfactory. In addition, p
-t-butylbenzoate aluminum or 1.
Propylene homopolymer compositions containing 3,2,4-dibenzylidene sorbitol have been shown to significantly improve stiffness, but are still difficult to use in applications that require high stiffness and heat-resistant stiffness. It's not completely satisfying. The present inventor conducted extensive research in order to solve the above-mentioned problems in terms of rigidity regarding propylene-based polymer compositions containing the various nucleating agents described above. As a result, a composition obtained by blending a phosphoric compound represented by the following general formula [1] (hereinafter referred to as compound A) with a propylene homopolymer having a specific isotactic pentad fraction was obtained. It was discovered that the problem of rigidity of propylene polymer compositions could be solved, and the present invention was completed based on this knowledge. (However, in the formula, R ₁ is a direct bond, sulfur or methylene group, or an alkylidene group having 2 to 4 carbon atoms,
R ₂ and R ₃ are each hydrogen or carbon number 1 to 8
the same or different alkyl groups, M is monovalent to
n represents a trivalent metal atom, and n represents an integer of 1 to 3. ) As is clear from the above description, an object of the present invention is to provide a propylene homopolymer composition that is extremely excellent in rigidity and heat-resistant rigidity. [Means for solving the problems] The present invention has the following configuration. The relationship between isotactic pentad fraction P and melt flow rate (MFR) is 1.00≧P≧
0.015logMFR + 0.955, and the isotactic pentad fraction P of extracts extracted sequentially with boiling n-hexane and boiling n-heptane, respectively.
0.01 to 1 part by weight of a phosphate compound represented by the following general formula [1] (hereinafter referred to as compound A) is blended with 100 parts by weight of a crystalline propylene homopolymer having a molecular weight of 0.450 to 0.700 and 0.750 to 0.930. Highly rigid propylene homopolymer composition. (However, in the formula, R ₁ is a direct bond, sulfur, a methylene group, or an alkylidene group having 2 to 4 carbon atoms,
R ₂ and R ₃ are each hydrogen or carbon number 1 to 8
the same or different alkyl groups, M is monovalent to
n represents a trivalent metal atom, and n represents an integer of 1 to 3. ) The propylene homopolymer used in the present invention has a relationship between isotactic pentad fraction P and melftrolate (MFR) of 1.00≧P≧
0.015logMFR+0.955, and the isotactic pentad fraction P of the extract sequentially extracted with boiling n-heptane is 0.450-0.700 and 0.700, respectively.
It is a crystalline propylene homopolymer with a molecular weight of 0.750 to 0.930. Such a propylene homopolymer is disclosed in Japanese Patent Application Laid-Open No. 58-104907 filed by the same applicant as the present application.
It can be manufactured by the manufacturing method described in the publication. That is, a solid product () obtained by reacting an organoaluminum compound or a reaction product of an organoaluminum compound and an electron donor with titanium tetrachloride is further reacted with an electron donor and an electron acceptor. A solid product () is combined with an organoaluminum compound and an aromatic carboxylic acid ester (), and the molar ratio of the aromatic carboxylic acid ester and the solid product () is ()/()=
It can be obtained by polymerizing propylene in the presence of a catalyst with a concentration of 0.2 to 10.0. Here, the isotactic pentad fraction is Macromolecules, Volume 6, Issue 6, November-December,
pp. 925-926 (1973) [Macromolecules,
Vol.6, No.6, November-December, 925-926
(1973)], i.e. ¹³ C−
This is the isotactic fraction in pentad units in the molecular chain of a propylene polymer measured using NMR. In other words, the fraction means the fraction of propylene monomer units in which five propylene monomer units are isotactically bonded consecutively.
The method for determining the attribution of spectral peaks in measurements using ¹³ C-NMR described above is described in Macromolecules, Vol. 8, No. 5, September-October, pp. 687-689 (1975) [Macromolecules, Vol. .8, No.5,
September-October, 687-689 (1975)]. Incidentally, in ^{the 13} C-NMR measurements in the Examples described later, a 270 MHz FT-NMR device was used, and through 27,000 cumulative measurements, the signal detection limit was improved to 0.001 in terms of isotactic pentad fraction. I went. The above isotactic pentad fraction P and melt flow rate (MFR)
The requirement for the relational expression is that the fraction P of a propylene homopolymer with a low MFR generally decreases, so the proportion P of the propylene homopolymer to be used is
The configuration requirement is to limit the lower limit value of P corresponding to MFR. Since the P is a fraction, the upper limit is 1.00. Next, the boiling n-hexane extract is usually added in a few percent to the propylene homopolymer.
The fraction P of this substance is, for example, 0.10 to
0.70, which can vary considerably depending on the propylene polymerization method. The propylene homopolymer used in the present invention must have a P value of the boiling n-hexane extract within the range of 0.450 to 0.700. A composition using a homopolymer with an extract P of less than 0.450 improves stiffness, but the improvement in heat resistance stiffness is insufficient. Similarly, the fraction P of the boiling n-heptane continuation extract is the isotactic bentad fraction of the extract obtained by further extracting the boiling n-heptane residue with boiling n-heptane. The propylene homopolymer used in the present invention has P of this boiling n-heptane extract.
Must be within the range of 0.750 to 0.930. Compositions using a homopolymer with a molecular weight of less than 0.750 have improved stiffness, but on the other hand, the improvement in heat-resistant stiffness is insufficient. The total amount of the sequential extracts with boiling n-hexane and boiling n-heptane is not limited, but the total amount in the raw material propylene homopolymer is often in the range of 1.0 to 10.0% by weight; Propylene homopolymers within this range will give better results than those outside this range. The above-mentioned sequential extraction is performed as follows. A small amount of antioxidant (for example, 0.1% by weight of 2,6-di-t-butyl-p-
A granulated product made by mixing cresol) and granulating it using an extruder is pulverized using a pulverizer, and the pulverized product is processed through a 20-mesh (Tyler) sieve, and 3 g of what passes through the 20-mesh is passed through a Soxhlet extractor. first 100 using
ml of boiling n-hexane, followed by 100ml of boiling n-hexane
- Extract with heptane for 6 hours each, add a poor solvent such as methanol to each extract to precipitate the soluble matter, and separate, dry and weigh the precipitate. Also, MFR is
Based on JISK7210, measured at 230℃ and a load of 2.16Kg. In addition, in the propylene homopolymer used in the present invention, propylene and ethylene, butene-1, bentene-1, 4-methyl-pentene-1, hexene-1, octene-1, etc. - Crystalline random copolymers or crystalline block copolymers with one or more olefins, copolymers of propylene with vinyl acetate, acrylic esters, etc. or saponified products of such copolymers, propylene with Copolymers with unsaturated carboxylic acids or their anhydrides, reaction products of the copolymers with metal ion compounds, modified propylene polymers obtained by modifying propylene polymers with unsaturated carboxylic acids or derivatives thereof, etc. It can also be used as a mixture, and various synthetic rubbers (e.g. ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene copolymer rubber, polybutadiene, polyisobrene, chlorinated polyethylene, chlorinated polypropylene, styrene-
Butadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-
styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-propylene-butylene-styrene block copolymer, etc.) or thermoplastic synthetic resins (such as polyethylene, polybutene, poly-4-methylpentene-1 Polyolefins, polystyrene, styrene-acrylonitrile copolymers, acrylonitrile-butadiene-styrene copolymers, polyamides, polyethylene terephthalate, polybutylene terephthalate, excluding propylene-based polymers such as
It is also possible to use a mixture of polyvinyl chloride, etc.). At this time, the mixture has the above 1.00≧P
≧0.015logMFR+0.955 and boiling n-
The P of extracts extracted sequentially with hexane and boiling n-heptane is 0.450-0.700 and 0.750-0.750, respectively.
It is sufficient as long as it satisfies 0.930. Compound A used in the present invention is sodium-
2,2'-methylene-bis-(4,6-di-t-butylphenyl) phosphate, sodium-
2,2'-ethylidene-bis-(4,6-di-t-
butyl phenyl) phosphate, lithium
2,2'-methylene-bis-(4,6-di-t-butylphenyl)phosphate, lithium-2,
2'-ethylidene-bis-(4,6-di-t-butylphenyl) phosphate, sodium-2,
2'-ethylidene-bis-(4-i-propyl-6
-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis-(4-methyl-6
-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis-(4-ethyl-6
-t-butylphenyl) phosphate, calcium-bis-[22'-thiobis-(4-methyl-6
-t-butylphenyl) phosphate], calcium-bis-[2,2'-thiobis-(4-ethyl-6-t-butylphenyl) phosphate],
Calcium-bis-[2,2'-thiobis-(4,6
-di-t-butylphenyl) phosphate],
Magnesium-bis-[2,2'-thiobis-(4,
6-di-t-butylphenyl) phosphate],
Magnesium-bis-[2,2'-thiobis-(4-
t-octylphenyl) phosphate], sodium-2,2'-butylidene-bis-(4,6-
di-methylphenyl) phosphate, sodium-2,2'-butylidene-bis-(4,6-di-
t-butylphenyl) phosphate, sodium-2,2'-t-octylmethylene-bis-(4,
6-dimethylphenyl) phosphate, sodium-2,2'-t-octylmethylene-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], Barium-bis-[2 ，
2'-methylene-bis-(4,6-di-t-butylphenyl) phosphate], sodium-2,
2'-methylene-bis-(4-methyl-6-t-butylphenyl) phosphate, sodium-
2,2'-methylene-bis-(4-ethyl-6-t
-butylphenyl) phosphate, sodium (4,4'-dimethyl-6,6'-di-t-butyl-
2,2'-biphenyl) phosphate, calcium bis-[(4,4'-dimethyl-6,6'-di-t
-butyl-2,2'-biphenyl) phosphate], sodium-2,2'-ethylidene-bis-
(4-s-butyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylene-
Bis-(4,6-di-methylphenyl)phosphate, sodium-2,2'-methylene-bis-
(4,6-di-ethylphenyl) phosphate,
Potassium-2,2'-ethylidene-bis-(4,6
-dibutylphenyl) phosphate, calcium-bis-[2,2'-ethylidene-bis-(4,
6-di-t-butylphenyl) phosphate],
Magnesium-bis-[2,2'-ethylidene-bis-(4,6-di-t-butylphenyl) phosphate], Barium-bis-[2,2'-ethylidene-bis-(4,6-di-t-t) -butylphenyl)
phosphate], aluminum-tris-[2,
2'-methylene-bis-(4,6-di-t-butylphenyl)phosphate] or aluminum-tris-[2,2'-ethylidene-bis-(4,6
-di-t-butylphenyl) phosphate]. Especially sodium-
2,2'-methylene-bis-(4,6-di-t-butylphenyl) phosphate is preferred. The blending ratio of compound A is the propylene homopolymer described above.
0.01 to 1 part by weight per 100 parts by weight, preferably
It is 0.05 to 0.5 part by weight. If the amount is less than 0.01 part by weight, the effect of improving stiffness and heat resistance stiffness will not be sufficiently exhibited, and although it is possible to exceed 1 part by weight, it is not only impractical as no further improvement can be expected. It is also uneconomical. In the composition of the present invention, various additives that are usually added to propylene polymers, such as phenol-based, thioether-based, phosphorus-based antioxidants, light stabilizers, clarifying agents, nucleating agents, Lubricants, antistatic agents, antifogging agents, antiblocking agents, non-drop agents,
Pigments, heavy metal deactivators (copper inhibitors), radical generators such as peroxides, dispersants or neutralizing agents such as metal soaps, inorganic fillers (e.g. talc,
mica, clay, wollastonite, zeolite, asbestos, calcium carbonate, aluminum hydroxide, magnesium hydroxide, barium sulfate, calcium silicate, glass fiber, carbon fiber, etc.) or coupling agents (e.g. silane, titanate, poron) The above-mentioned inorganic fillers or organic fillers (e.g., wood flour, pulp, waste paper, synthetic fibers, natural fibers, etc.) that have been surface-treated with a surface treatment agent such as , aluminate-based, zircoaluminate-based, etc.)
may be used in combination without impairing the purpose of the present invention. In particular, when an inorganic filler is used in combination, the rigidity and heat-resistant rigidity are further improved, so it is preferable to use the inorganic filler in combination. The composition of the present invention is prepared by mixing the propylene homopolymer according to the present invention with predetermined amounts of Compound A and the various additives mentioned above that are normally added to propylene polymers using a conventional mixing device such as a Hensel mixer. (product name), super mixer, ribbon blender, banbari mixer, etc.
Using a normal single screw extruder, twin screw extruder, Brabender or roll, melt kneading temperature is 170℃~300℃,
It can be obtained preferably by melt-kneading and pelletizing at 200°C to 250°C. The obtained composition is used to produce a desired molded article by various molding methods such as injection molding, extrusion molding, and blow molding. [Function] In the present invention, the phosphate compound represented by Compound A is generally known to act as a nucleating agent to improve stiffness and heat-resistant stiffness, as disclosed in JP-A-58-1736. However, by blending Compound A with the propylene homopolymer having a specific isotactic pentad fraction according to the present invention, a surprising synergistic effect that could not be predicted from the blending of conventionally known nucleating agents was exhibited. It has been found that a composition having significantly superior rigidity and heat-resistant rigidity can be obtained. [Effects] The composition of the present invention is significantly superior in (1) rigidity and heat-resistant rigidity compared to conventionally known compositions of propylene homopolymer compositions containing various nucleating agents. (2) Not only can the molded product be made thinner, contributing to resource conservation, but also the cooling rate during molding is faster, which increases the molding speed per unit time, contributing to improved productivity. can. (3) It is now possible to use polypropylene resin in applications where polystyrene, ABS resin, polyester, etc. have traditionally been used, making it possible to expand the applications of polypropylene resin. [Examples] Hereinafter, the present invention will be specifically explained using Examples and Comparative Examples, but the present invention is not limited thereto. The evaluation method used in Examples and Comparative Examples was as follows. () Stiffness: length using the obtained pellets
A test piece of 100 mm, width 10 mm, and thickness 4 mm was prepared by injection molding, and the rigidity was evaluated by measuring the bending elastic modulus (based on JIS K7203) using the test piece. () Heat-resistant rigidity: Using the obtained pellets, a test piece with a length of 130 mm, width of 13 mm, and thickness of 6.5 mm was created by injection molding, and the heat distortion temperature was measured using the test piece (based on JIS K7207; The heat-resistant rigidity was evaluated by applying a load of 4.6 Kgf/ ^cm3 . Examples 1 to 3, Comparative Examples 1 to 10 Sodium-based compound A was added to 100 parts by weight of a powdered crystalline propylene homopolymer having each MFR and each isotactic pentad fraction shown in Table 1 below. 2,2'-methylene-bis-(4,
6-di-t-butylphenyl) phosphate and other additives in the mixing ratios listed in Table 1 below in a Hensel mixer (trade name), stirred and mixed for 3 minutes, and then poured into a 40 mm diameter unit. The mixture was melt-kneaded using a screw extruder at 200°C to form pellets. Additionally, as Comparative Examples 1 to 10, additives listed in Table 1 below were added to 100 parts by weight of powdered crystalline propylene homopolymer having each MFR and each isotactic pentad fraction shown in Table 1 below. Predetermined amounts of each were blended and melt-kneaded according to Examples 1 to 3 to obtain pellets. The test pieces used for rigidity and heat resistance stiffness tests were obtained by heating the pellets at a resin temperature of 250°C and a mold temperature of 50°C.
It was prepared by injection molding. Using the obtained test piece, rigidity and heat-resistant rigidity were evaluated by the above-mentioned test method. These results are shown in Table 1. Examples 4 to 6, Comparative Examples 11 to 20 Sodium-based compound A was added to 100 parts by weight of a powdered crystalline propylene homopolymer having each MFR and each isotactic pentad fraction shown in Table 2 below. 2,2'-methylene-bis-(4,
6-di-t-butylphenyl) phosphate,
Predetermined amounts of particulate talc with an average particle size of 2 to 3μ as an inorganic filler and other additives were placed in a Hensel mixer (trade name) at the mixing ratios listed in Table 2 below, and after stirring and mixing for 3 minutes. The mixture was melt-kneaded at 200°C using a single-screw extruder with a diameter of 40 mm to form pellets. In addition, as Comparative Examples 11 to 20, additives listed in Table 2 below were added to 100 parts by weight of powdered crystalline propylene homopolymers having each MFR and each isotactic pentad fraction shown in Table 2 below. Predetermined amounts of each were blended and melt-kneaded according to Examples 4 to 6 to obtain pellets. The test pieces used for rigidity and heat resistance stiffness tests are the pellets obtained at a resin temperature of 250°C and a metal temperature of 50°C.
It was prepared by injection molding. Using the obtained test piece, rigidity and heat-resistant rigidity were evaluated by the above-mentioned test method. The results are shown in Table 2. The compounds and additives according to the present invention shown in Tables 1 and 2 are as follows. Compound A: Sodium-2,2'-methylene-bis-(4,6-di-t-butylphenyl) phosphate (MARK manufactured by Adeka Argus Chemical Co., Ltd.)
NA-11) Nucleating agent 1; Aluminum pt-butylbenzoate Nucleating agent 2; 1,3,2,4-dibenzylidene sorbitol Nucleating agent 3; Sodium-bis-(4-t-butylphenyl)phos Phatephenol antioxidant 1; 2,6-di-t-butyl-p-cresol phenolic antioxidant 2; Tetrakis[methylene-3-(3',5'-di-t-butyl-4') -Hydroxyphenyl)propionate] Methanophosphorus antioxidant; Tetrakis (2,4-di-t
-butylphenyl)-4,4'-biphenylene-di-phosphonite Ca-St; Calcium stearate Inorganic filler; Talc (average particle size 2-3μ)

【table】

【table】

【table】

[Table] Each practical example and each comparative example listed in Table 1 is a propylene-based polymer.
This is the case when crystalline propylene homopolymers having MFR and various isotactic pentad fractions are used. As can be seen from Table 1, Examples 1-
Examples 1 to 3 are compounds in which Compound A is blended with a crystalline propylene homopolymer having an isotactic pentad fraction within the range of the present invention.
Comparing with Comparative Examples 1 to 4 (in which Compound A and other nucleating agents were blended with a crystalline propylene homopolymer having an isotactic pentad fraction outside the range of the present invention), it was found that It can be seen that Examples 1 to 3 have excellent rigidity and heat resistance rigidity. Furthermore, when comparing Comparative Examples 5 to 7 in which no organic nucleating agent was used for a crystalline propylene homopolymer having an isotactic pentad fraction within the scope of the present invention and Examples 1 to 3, Comparative Examples Nos. 5 to 7 are still not sufficiently effective in improving rigidity and heat resistance rigidity. Furthermore, Comparative Examples 8 to 10 and Examples 1 to 3 in which an organic nucleating agent consisting of a compound other than Compound A was used in a crystalline propylene homopolymer having an isotactic pentad fraction within the scope of the present invention. Comparatively, Comparative Examples 8 to 10 show considerable improvement in stiffness and heat-resistant stiffness, but are still not sufficient. Examples 1-3 have significantly superior stiffness and heat-resistant stiffness, and the use of Compound A significantly It can be seen that a synergistic effect is observed. That is, the stiffness and heat-resistant stiffness obtained in the present invention are due to the unique effects observed when Compound A is used in a crystalline propylene homopolymer having an isotactic pentad fraction within the range limited in the present invention. You can say that. Table 2 shows the results in which Compound A and talc as an inorganic filler were used in combination with the propylene polymer used in Table 1, and the same effect as described above was confirmed with this as well. This shows that the composition of the present invention is significantly superior in terms of rigidity and heat-resistant rigidity compared to conventionally known compositions made by blending a nucleating agent with a crystalline propylene homopolymer. The remarkable effects of the composition of the present invention were confirmed.

Claims (1)

[Claims] 1. The relationship between the isotactic pentad fraction P and the melt flow rate (MFR) is 1.00≧P≧
logMFR+0.955, and the isotactic pentad fraction P of extracts extracted sequentially with boiling n-hexane and boiling n-heptane is 0.450, respectively.
~0.700 and 0.750 ~ 0.930 per 100 parts by weight of crystalline propylene homopolymer, a phosphonate compound represented by the following general formula [1] (hereinafter referred to as
It is called compound A. ) A highly rigid propylene homopolymer composition containing 0.01 to 1 part by weight. (However, in the formula, R ₁ is a direct bond, sulfur, a methylene group, or an alkylidene group having 2 to 4 carbon atoms,
R ₂ and R ₃ are each hydrogen or carbon number 1 to 8
the same or different alkyl groups, M is monovalent to
n represents a trivalent metal atom, and n represents an integer of 1 to 3. ) 2 In general formula [1], R ₁ is a methylene group,
The highly rigid propylene homopolymer composition according to claim 1, wherein R ₂ and R ₃ are t-butyl groups. 3 Sodium-2,2'-methylene-bis-(4,6-di-t-butylphenyl) as compound A
The highly rigid propylene homopolymer composition according to claim 1, which contains phosphate. 4. The highly rigid propylene homopolymer composition according to claim 1, which contains an inorganic filler. 5 Talc, mica, clay, as inorganic fillers
Claims using one or more selected from wollastonite, zeolite, asbestos, calcium carbonate, aluminum hydroxide, magnesium hydroxide, barium sulfate, calcium silicate, glass fiber, carbon fiber, or potassium titanate. 5. Highly rigid propylene homopolymer composition according to item 4.