JPH0762097B2 - Crystalline polypropylene resin composition and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a crystalline polypropylene resin composition containing a polymer obtained by polymerizing a specific monomer and a method for producing the same.

[Conventional technology]

Crystalline polypropylene is a general-purpose polymer having relatively high rigidity and excellent transparency, and is used for various purposes. It is also known to copolymerize polypropylene with other α-olefins such as ethylene for the purpose of improving the impact resistance of polypropylene, especially at low temperatures. (For example, Japanese Patent Publication 44-
20621, JP-B-49-24593, JP-B-49-12589, etc.) It is well known to add various nucleating agents for the purpose of improving the properties of crystalline polypropylene, particularly the rigidity, the transparency of molded articles, etc. Among them, the method using a polymeric nucleating agent (for example, JP-A-60-139710, 60-139731, etc.) is excellent in that the addition of a very small amount is effective without the problem that the nucleating agent bleeds from the molded product. Is the way.

[Problems to be solved by the invention]

The method using the above-mentioned polymer nucleating agent is an extremely excellent method, but it is necessary to use a special monomer that is relatively difficult to obtain, and it is desired to use a more effective polymer.

[Means for solving problems]

The present inventors diligently studied an effective polymer nucleating agent,
The present invention was completed by finding that the physical properties of crystalline polypropylene are improved by adding a polymer obtained by polymerizing a specific monomer.

That is, 1 selected from the group consisting of 4,4-dimethylpentene-1,4,4-dimethylhexene-1, indene, trialkylvinylsilane and trialkylallylsilane using a transition metal catalyst and a catalyst composed of an organoaluminum compound. 0.01-1000wtppm polymer obtained by polymerizing seed monomers
It is a crystalline polypropylene resin composition characterized by being contained.

The present invention also provides a manufacturing method suitable for synthesizing the above composition. That is, using a catalyst composed of a transition metal catalyst and an organoaluminum compound, 4,4-dimethylpentene-1,4,4-dimethylhexene-1, indene,
By polymerizing one monomer selected from the group consisting of trialkylvinylsilane and trialkylallylsilane, and then polymerizing propylene, the content of the polymer consisting of one monomer selected becomes polypropylene. On the other hand, 0.1
A polypropylene having a content of .about.10000 wtppm is obtained and then mixed with another crystalline polypropylene so that the content of the polymer composed of one monomer selected in the whole composition is 0.1.
It is a method for producing a crystalline polypropylene resin composition having an amount of 01 to 1000 wtppm.

The transition metal catalyst and the catalyst comprising an organoaluminum compound in the present invention are not particularly limited, and various known catalyst systems which give polypropylene having high stereoregularity can be used. Titanium halide is preferably used as the transition metal catalyst.
A catalyst system comprising titanium trichloride obtained by reduction with hydrogen or organoaluminum or those modified with an electron donating compound and an organoaluminum compound, if necessary, and a stereoregularity improver such as an oxygen-containing organic compound, Alternatively, a catalyst comprising a carrier such as magnesium halide or a product obtained by supporting titanium halide on a carrier obtained by treating them with an electron-donating compound, an organoaluminum compound and optionally a stereoregularity improving agent such as an oxygen-containing compound. The system is exemplified. (For example, various examples are described in the following literature. Ziegler-Natta Catalysts and Polymeriz.
ation by John Boar Jr (Academic Press), Journal o
f Makromolecular Sience-Reviews in Makromolecular
Chemistry and Physics C24 (3) 355-385 (1984)
C25 (1) 57-97 (1985)) Here, oxygen-containing compounds such as ethers, esters, orthoesters, and alkoxysilicons can be preferably used as the stereoregularity improver or electron donor, and alcohol is further used as the electron donor. ,
Aldehydes and water can also be used.

As the organoaluminum compound, trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, and alkylaluminum dihalide can be used, and the alkyl group is exemplified by methyl group, ethyl group, propyl group, butyl group, hexyl group, and the like. Examples of chlorine include bromine and iodine.

Preferred titanium halides are titanium tetrachloride obtained by reducing titanium tetrachloride with aluminum or organoaluminum, modified with ether or ester, or titanium tetrachloride obtained by co-milling magnesium chloride and an organic compound. Or a reaction product of magnesium chloride and alcohol dissolved in a hydrocarbon solvent and then treated with a precipitating agent such as titanium tetrachloride to make it insoluble in the hydrocarbon solvent and, if necessary, electron donating properties such as ester and ether. It is a supported titanium halide obtained by modification with a compound and then with titanium tetrachloride.

In the present invention, first, one monomer selected from the group consisting of 4,4-dimethylpentene-1,4,4-dimethylhexene-1, indene, trialkylvinylsilane and trialkylallylsilane using the above catalyst. Is polymerized to produce a polymer. Examples of trialkylvinylsilane and trialkylallylsilane include methyl residues such as methyl, ethyl, propyl, butyl, pentyl, and hexyl groups. The polymerization is carried out in the presence or absence of an inert medium (eg, butane, pentane, hexane, heptane, octane, nonane, decane, etc., or a mixture) at 0 ° C to 100 ° C, usually at room temperature to 80 ° C.

The composition according to the present invention may also be obtained by polymerizing propylene subsequent to the above polymerization so that the polymer consisting of the selected monomer in the polymer becomes 0.01 to 1000 wtppm, or by the above method. Obtained, the polymer consisting of the selected monomer can also be obtained by simply mixing so as to be 0.01 to 1000 wtppm, preferably, by polymerizing propylene following the polymerization of the selected monomer, By obtaining polypropylene such that the content of the polymer composed of the selected monomer is 0.1 to 10000 wtppm, and then mixing with other crystalline polypropylene, the composition of the selected monomer in the entire composition is obtained. The polymer content should be 0.01-1000wtppm.

Here, the polymerization of propylene is usually carried out under the same conditions as those used in the polymerization of the monomer selected earlier, under normal pressure to
In the polymerization of propylene, which is carried out under a pressure of 50 kg / cm ² -Geesi, it is also possible to carry out the polymerization in the presence of an α-olefin such as ethylene, butene-1, pentene-1, hexene-1 if necessary. As the crystalline polypropylene used for mixing, not only a propylene homopolymer but also a random or block copolymer with an α-olefin such as ethylene, butene-1, pentene-1, hexene-1 can be exemplified. These can be produced, for example, by polymerizing by a known method using the above-mentioned transition metal catalyst and a catalyst comprising an organoaluminum compound. When mixing, the method adopted for blending ordinary polymers, namely Henschel mixer, Brabender Banbury mixer,
It can be performed using an apparatus such as an extruder.

The content of the polymer composed of the monomer selected here is required to be 0.01 to 1000 wtppm in the crystalline polypropylene resin composition, and if it is less than 0.01 wtppm, there is almost no effect on the improvement of physical properties and it is used more than 1000 wtppm. However, on the contrary, due to the effect of improving the physical properties, on the contrary, the appearance of the molded article becomes poor, which is not preferable. Further, the content of the polymer of the selected monomer used in the polypropylene in the mixing is preferably 0.1 to 10000 wtppm, and when it is less than 0.1 wtppm, the proportion of the other crystalline polypropylene used increases,
In terms of operation, it becomes difficult, and if it is more than 10000 wtppm, the proportion of other crystalline polypropylene used becomes too small,
It is difficult to mix uniformly, which is not preferable.

〔Example〕

 The present invention will be further described below with reference to examples.

Reference Example 1 A vibration mill equipped with four grinding pots with an internal volume of 4 containing 9 kg of steel balls having a diameter of 12 mm is prepared. 300 g magnesium chloride and tetraethoxysilane in a nitrogen atmosphere in each pot
60 ml and 45 ml of α, α, α-trichlorotoluene were added and crushed for 40 hours.

300 g of the above co-ground product was placed in a flask of 5 and titanium tetrachloride was added.
1.5, toluene and 1.5 were added and the mixture was stirred at 100 ° C. for 30 minutes. Then, the mixture is allowed to stand and the supernatant is removed. Similarly, titanium tetrachloride (1.5) and toluene (1.5) are added, and the mixture is stirred at 100 ° C for 30 minutes. Then, the supernatant is removed and the solid content is further added using n-heptane (4). The solid catalyst slurry thus obtained was repeatedly washed 10 times, and 1 part of the solid catalyst slurry was sampled to analyze the titanium content, which was 1.9 wt%.

Using an autoclave with an internal volume of 5, 30m of the above solid catalyst
g, diethyl aluminum chloride 0.128 ml, p-methyl methyltoluate 0.08 ml, triethylaluminum 0.10 ml, propylene 1.5 kg and hydrogen 3.3N are added and polymerized at 75 ° C for 2 hours to purge unreacted propylene and take out powder to dry. This gave 540 g of polypropylene. The intrinsic viscosity measured with a 135 ° C. tetralin solution was 1.62, and it was extracted with boiling n-heptane using a Soxhlet extractor for 6 hours. The extraction residual rate (hereinafter abbreviated as II) was 96.5%.

Reference Example 2 Using the solid catalyst obtained in Reference Example 1, a propylene block copolymer was produced. 30 mg of solid catalyst, 0.128 ml of diethylaluminum chloride, in an autoclave with an internal volume of 5,
Methyl p-toluate 0.08 ml, triethylaluminum
Add 0.04 ml and add 1.5 kg of propylene and 3.3 N of hydrogen and add 75 ° C.
Polymerize for 2 hours, then lower the internal temperature to 40 ° C, add 5 kg / cm ² -gauge of ethylene, and add 0.3 ml of triethylaluminum so that the ethylene partial pressure becomes 5 kg / cm ² -gauge. Polymerization was carried out for 60 minutes while adding ethylene. Unreacted propylene and ethylene were purged and dried to obtain 620 g of a block copolymer having an ethylene content of 8.5 wt%.

Examples 1 to 5, Comparative Examples 1, 2 and 3 Using the solid catalyst obtained in Reference Example 1 in an autoclave with an internal volume of 2 0.5 g of solid catalyst, diethylaluminum chloride
1.2 ml and 0.6 ml of methyl p-toluate were added, and hexane 20 was added.
0 ml and 4,4-dimethylpentene-1 (Example 1), 4,4-
2 ml each of dimethylhexene-1 (Example 2), indene (Example 3), trimethylallylsilane (Example 4) and trimethylvinylsilane (Example 5) were added, and the mixture was heated to 50 ° C.
After reacting for 1 hour at room temperature, 1 ml of triethylaluminum was added and 1 of heptane was added.
Then, 200 g (Examples 1, 2, and 3) and 20 g (Examples 4 and 5) of propylene were charged.

The obtained polymer was filtered and dried. The content of 4,4-dimethylpentene-1 etc. in each polymer was 140
wtppm (Example 1), 110wtppm (Example 2), 30wtppm
(Example 3), 1100 wtppm (Example 4), 980 wtppm (Example 5).

In Examples 1, 2 and 3, the polypropylene 100 obtained in Reference Example 1 was mixed at a ratio of 10 (weight ratio), and
In Comparative Example 1, the polymer obtained in Reference Example 1 alone was granulated by adding 10/10000 weight ratio of the phenolic stabilizer and 15/10000 weight ratio of calcium stearate, respectively.
Regarding 5, the ratio was 1 weight ratio to 100 of the polypropylene block copolymer obtained in Reference Example 2, in Comparative Example 2 the block copolymer of Reference Example 2 alone, and in Comparative Example 3 Reference Example 2 The block copolymer was added at a ratio of 1/10000 and granulated in the same manner. The melt flow index was measured for each, an injection sheet having a thickness of 1 mm was prepared, and the following physical properties were measured.

Melt flow index ASTM D1238 (230 ° C) Tensile Strength ASTM D638-64T (20 ° C) Bending Rigidity ASTM D747-63 (20 ° C) was measured, and further Izod (with notch) for Examples 4 and 5 and Comparative Examples 2 and 3. Impact strength ASTM D256-5
6 (20 ℃, -10 ℃), DuPont impact strength JIS K6718 (20
Table 1 shows the results of measurement of (° C, -10 ° C).

[Effect]

The composition according to the present invention is a crystalline polypropylene resin composition having an excellent physical property balance, which is of great industrial significance, and according to the present invention, a crystalline polypropylene resin composition having an excellent physical property balance can be easily prepared. It can be manufactured and is of great industrial value.

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Claims (2)

[Claims] 1. A 4,4-dimethylpentene-1,4,4-using a catalyst comprising a transition metal catalyst and an organoaluminum compound.
0.01-1000wt of polymer obtained by polymerizing one kind of monomer selected from the group consisting of dimethylhexene-1, indene, trialkylvinylsilane and trialkylallylsilane.
A crystalline polypropylene resin composition characterized by containing ppm. 2. A 4,4-dimethylpentene-1,4,4-using a catalyst comprising a transition metal catalyst and an organoaluminum compound.
Polymerization of one kind of monomer selected from the group consisting of dimethylhexene-1, indene, trialkylvinylsilane and trialkylallylsilane, and then polymerization of propylene to form one kind of monomer selected. A polypropylene having a polymer content of 0.1-10000 wtppm with respect to polypropylene was obtained and then mixed with another crystalline polypropylene to obtain a polymer consisting of one monomer selected in the entire composition. A method for producing a crystalline polypropylene resin composition having a content of 0.01 to 1000 wtppm.