JP2909871B2 - Method for producing modified propylene-based random copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a modified propylene-based random copolymer and a molded article. More specifically, a method for producing a modified propylene-based random copolymer, which has a high melt tension, is excellent in moldability, and can be recycled after being used as a molded article and then re-melted, The present invention relates to a molded article using the obtained modified polypropylene random copolymer.

[0002]

2. Description of the Related Art Polypropylene is widely used in various molding fields because it has excellent mechanical properties, chemical resistance and the like, and is extremely useful in balance with economic efficiency. However, since the melt tension is small, moldability such as hollow molding, foam molding, and extrusion molding is poor.

As a method for increasing the melt tension and the crystallization temperature of polypropylene, a method of reacting an organic peroxide and a crosslinking assistant with polypropylene in a molten state (JP-A-59-93711, JP-A-61-1986) −152754
However, there is a problem that an odor remains in the modified polypropylene obtained by using the crosslinking aid. In addition, the melt tension is not sufficiently improved, and if the amount of the organic peroxide and the crosslinking aid is increased to increase the melt tension, a gel will be generated. It was impossible to do that.

Japanese Patent Application Laid-Open No. 5-19459 discloses that a random copolymer of propylene and 1,9-decadiene exhibits a high melt tension.
JP-A-121222 and JP-A-5-222122 disclose polypropylene having a high melt tension by polymerizing propylene using a catalyst which has been subjected to a prepolymerization treatment by random copolymerization of propylene or ethylene with 1,9-decadiene. Have been disclosed. However, when the present inventors conducted additional tests based on these disclosed technologies using 1,9-decadiene, the obtained polypropylene had a certain degree of improvement in melt tension at the powder stage, but the granulated pellets had In the state, the improvement of the melt tension was insufficient.

Japanese Patent Publication No. 44-29742 does not mention the melt tension, but propylene and ethylene and 1,7-octadiene tertiary random copolymer or the tertiary random copolymer is used as a block segment. A method for modifying a propylene copolymer for melting and kneading one block copolymer and an organic peroxide to improve impact resistance at a low temperature is disclosed. According to the results of studies by the present inventors, the improvement in melt tension was extremely insufficient with the diene content and the amount of organic peroxide in the copolymers shown in the examples of the publication.

On the other hand, JP-A-57-98534 and JP-A-4-28706 disclose 1,4-dienes and random copolymers of propylene and 7-methyl-1,6-octadiene with propylene. A technique for obtaining a crosslinked product having a high gel fraction using an oxide or an electron beam has been disclosed.However, polypropylene obtained by the disclosed technique has an improved melt tension, but has a high gel fraction. After being used as a molded article, it was impossible to re-melt and reuse it.

[0007]

As described above, the polypropylene obtained by the method of the prior art is not sufficient in improving the melt tension, but also has an odor and contains a gel. There was a problem that it was not possible to re-melt and reuse the product after using it as a product.

The present inventors have intensively studied to solve the problems of the prior art and to invent a method for producing polypropylene suitable for hollow molding, foam molding, extrusion molding and the like. As a result, a modified propylene-based random copolymer is obtained by heat-treating a random copolymer of propylene and polyene, and, if necessary, an olefin other than propylene and an organic peroxide under specific conditions. It has been found that the use of a high-molecular-weight propylene-based random copolymer as a molded article solves the above-mentioned problems of the prior art, and has led to the present invention.

As is apparent from the above description, the object of the present invention is to provide a modified product having an extremely high melt tension, excellent moldability, and, after being used as a molded article, can be re-melted and recycled. An object of the present invention is to provide a method for producing a propylene-based random copolymer.

[0010]

The present invention has the following configuration (1). (1) A propylene system having a propylene content of 99.9 to 70 mol%, a polyene content of 0.1 to 10 mol%, and an olefin content of 2 to 12 carbon atoms other than propylene having a content of 0 to 20 mol%. Random copolymer 100
0.001 to 1 part by weight of an organic peroxide is added to and mixed with the parts by weight, and the resulting mixture is heat-treated at 80 to 350 ° C. to (A) melt tension at 230 ° C. (M
S) and the intrinsic viscosity [η] measured at 135 ° C. in tetralin are such that log (MS)> 4.24 × log [η].
A method for producing a modified propylene-based random copolymer, which has a relationship represented by -0.915 and (B) a boiling xylene extraction residual ratio of 1% by weight or less.

The configuration and effect of the present invention will be described in detail below. The modified propylene-based random copolymer obtained by the method of the present invention has the following two essential requirements. That is, (A) the melt tension (MS) at 230 ° C. and the intrinsic viscosity [η] measured in tetralin at 135 ° C.
g (MS)> 4.24 log [η] −0.915, and (B) the boiling xylene extraction residual ratio satisfies 1% by weight or less.

As described above, the melt tension of the modified propylene-based random copolymer required to achieve the object of the present invention is determined by measuring the melt tension at 230 ° C. (MS) and the intrinsic tension measured at 135 ° C. in tetralin. Viscosity [η] is log
(MS)> 4.24 log [η] −0.915, more preferably log (MS)> 4.24 log
It is necessary to have a relationship represented by g [η] −0.740, most preferably a relationship represented by log (MS)> 4.24 log [η] −0.615.

Here, the melt tension at 230 ° C. (M
S) uses a melt tension tester type 2 manufactured by Toyo Seiki Seisaku-Sho, Ltd. to heat the polymer to 230 ° C. in the apparatus and feed the molten polymer from a 2.095 mm diameter nozzle at a speed of 20 mm / min. The strand was extruded into the atmosphere at 23 ° C. to form a strand, and the tension of the filamentous polymer when the strand was taken off at a speed of 3.14 m / min was measured, and the melt tension (M
S).

The modified propylene random copolymer obtained by the method of the present invention also has a boiling xylene extraction residual ratio as a measure of gel content of 1% by weight or less, more preferably 0.7% by weight, as described above. Below, it is most preferable that the content be 0.5% by weight or less. If the extraction residual ratio is large, the moldability at the time of molding a molded article using the obtained modified propylene random copolymer is deteriorated, and after using the modified propylene random copolymer as a molded article, It becomes extremely difficult to re-melt and recycle.

The boiling xylene extraction residue was determined by placing 1 g of the polymer in a 200-mesh wire net using a Soxhlet extractor, extracting the mixture with boiling xylene using 200 ml of p-xylene for 6 hours, and drying and weighing the extraction residue. , (Weight of extraction residue / weight before extraction) × 100%.

Next, a method for producing the modified propylene-based random copolymer of the present invention having the above-mentioned characteristic requirements will be described. The propylene random copolymer used in the method for producing a modified propylene random copolymer of the present invention is a random copolymer of propylene and polyene, or propylene, polydiene, and an olefin having 2 to 12 carbon atoms other than propylene. A random copolymer with an olefin having an intrinsic viscosity [η] of 0.5 to 6 dl / g measured at 135 ° C. in tetralin, particularly preferably 0.7 to 5 d
1 / g is preferred from the viewpoint of moldability.

The polyene used in the production of the propylene-based random copolymer according to the present invention is a compound having at least two carbon-carbon double bonds in the molecule. Is mentioned. 1,4-hexadiene, 1,5-hexadiene, 1,6-heptadiene, 1,6-octadiene, 1,7-octadiene,
1,8-nonadiene, 1,9-decadiene, 1,5,9
Linear aliphatic polyenes such as -decatriene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 5-methyl-1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 6-methyl-1,5-octadiene, 6-methyl-1,6-octadiene, 5,6-dimethyl-1,
6-octadiene, 7-methyl-1,6-octadiene, 7-methyl-1,6-decadiene, 7-ethyl-
Branched aliphatic polyene such as 1,6-decadiene, vinylcyclohexene, vinylnorbornene, ethylidene norbornene, dicyclopentadiene, cyclooctadiene, 2,5-norbornadiene, 1,3-divinylcyclopentane, 1,3-divinylcyclohexane, 1,4
-Divinylcyclohexane, 1,5-divinylcyclooctane, 1-allyl-4-divinylcyclohexane,
Alicyclic polyenes such as 1,4-diallylcyclohexane, 1,5-diallylcyclooctane, 1,3,4-trivinylcyclohexane, 1-isopropenyl-4-vinylcyclohexane, divinylbenzene and vinylisopropenylbenzene; And aromatic polyene.

These polyenes can be used alone or in combination of two or more. Further, among these polyenes, polyenes having 7 or more carbon atoms are more preferably used.

Specifically, 1,6-heptadiene, 1,
6-octadiene, 1,7-octadiene, 1,9-decadiene, 1,5,9-decatriene, 4-methyl-
1,4-hexadiene, 5-methyl-1,4-hexadiene, 6-methyl-1,5-heptadiene, 6-methyl-1,5-octadiene, 6-methyl-1,6-octadiene, 7-methyl- 1,6-octadiene, 1,3-
Divinylcyclopentane, 1,4-divinylcyclohexane, 1,5-divinylcyclooctane, 1-allyl-
4-divinylcyclohexane, 1,4-diallylcyclohexane, 1,3,4-trivinylcyclohexane and divinylbenzene.

Of these, more preferred are those having 8 carbon atoms.
Among the above polyenes, polyenes having 9 or more carbon atoms are particularly preferable, and specific examples thereof include 1,9-decadiene and 7-methyl-1,6-octadiene.

The propylene-based random copolymer according to the present invention has a carbon number of 2 to 1 other than propylene used in the production.
Examples of the olefin 2 include the following olefins. Ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4,
4-dimethyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 3-ethyl-1
-Hexene, 4-ethyl-1-hexene, styrene and the like. These olefins can be used alone or in combination of two or more.

The content of each component in the propylene random copolymer used in the present invention is as follows: propylene content is 99.9 to 70 mol%, polyene content is 0.1 to 10 mol%, and propylene is Other than 2 to 1 carbon atoms
Suitably, the olefin content of No. 2 is in the range of 0 to 20 mol%. Preferably, the propylene content is between 99.5 and 85.
Mole%, polyene content of 0.5 to 5 mole%, and olefin content of 2 to 12 carbon atoms other than propylene of 0 to 10 mole%. Most preferably, the propylene content ranges from 99.5 to 95 mol% and the polyene content ranges from 0.5 to 5 mol%.

If the polyene content is less than 0.1 mol%, the resulting modified propylene-based random copolymer cannot sufficiently improve the melt tension, and the object of the present invention cannot be achieved. Also,
If the polyene content exceeds 10 mol%, the productivity of the propylene-based random copolymer itself is poor, and the propylene-based random copolymer and the modified propylene-based random copolymer become tacky or have heat resistance or heat resistance. It is not preferable because the rigidity is reduced and a gel is easily generated in the modified propylene-based random copolymer.

The content of the olefin having 2 to 12 carbon atoms other than propylene, which is used if necessary, is preferably 0 to 10 mol%. Suitably 0 to 5 mol% is preferred. Further, from the viewpoint of the rigidity and heat resistance of the obtained modified propylene-based random copolymer, it is preferable that the olefin other than propylene is not contained. If the content of the olefin other than propylene exceeds 10 mol%, the heat resistance and rigidity of the propylene-based random copolymer and the modified propylene-based random copolymer decrease, and the inherent properties of polypropylene are lost.

The above-mentioned propylene random copolymer used in the present invention comprises a catalyst component of an organometallic compound containing a catalyst component of a transition metal compound and a metal selected from Groups 1 to 3 of the Periodic Table; And a propylene-based random copolymer obtained by copolymerizing propylene and a polyene, and if necessary, an olefin other than propylene using a catalyst comprising an electron donor.

Examples of the catalyst component of the transition metal compound include compounds containing a transition metal selected from Groups 3 to 8 of the periodic table. Specifically, Ti, Z
1 selected from r, Hf, Nb, Ta, Cr and V
Compounds containing more than one transition metal are included.

Examples of such a transition metal compound catalyst component include known catalyst components for olefin polymerization. Specific examples include a titanium compound, a magnesium compound, and, if necessary, oxygen and nitrogen in the molecule. , Phosphorus, a supported catalyst component obtained by contacting an electron donor containing at least one of sulfur, titanium, magnesium, halogen and, if necessary, an electron donor, and reduction of titanium tetrachloride. And a titanium trichloride-based catalyst component obtained by contacting the obtained titanium trichloride composition with a tetravalent titanium compound and / or an electron donor. Further, a metallocene compound obtained by contacting a cyclopentadienyl compound with a transition metal compound can also be used. As the metallocene compound, an inorganic compound such as SiO ₂ or Al ₂ O ₃ or a compound supported on a polymer compound such as polyethylene or polypropylene can be used.

Examples of the organometallic compound catalyst component containing a metal selected from Groups 1 to 3 of the periodic table include, specifically, trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, and aluminoxane. Organoaluminum compounds are preferably used.

Further, as the electron donor used as required, any one of oxygen, nitrogen, phosphorus and sulfur can be used in the molecule.
Examples include compounds containing at least one or more species, and specifically, organosilicon compounds having an Si-O bond, esters, ethers, and the like are preferably used.

Using a catalyst obtained by combining the above transition metal compound catalyst component, an organometallic compound catalyst component containing a metal selected from Groups 1 to 3 of the periodic table, and, if necessary, an electron donor. Propylene and polyene by a slurry polymerization in which the polymerization is carried out in an inert solvent, a bulk polymerization using the monomer itself as a solvent, a gas phase polymerization mainly using a monomer gas, or a known polymerization method combining these,
Further, a propylene-based random copolymer obtained by further polymerizing an olefin other than propylene as necessary is used in the present invention.

Since the propylene random copolymer needs to be mixed with an organic peroxide, the propylene random copolymer may be in a state immediately after completion of the polymerization step obtained by the above-described various methods and before pelletization. Is a preferred form.

The organic peroxide used in the present invention is:
Usually, a known organic peroxide can be used.
Specifically, when the half-life is 1 minute, the decomposition temperature is 80-2.
An organic peroxide exhibiting about 70 ° C., i-butyl peroxide (1 minute half-life temperature: 89 ° C., the same applies hereinafter),
2,4-dichlorobenzoyl peroxide (111
° C), o-chlorobenzoyl peroxide (111
° C), o-methylbenziyl peroxide (113
° C), bis-3,5,5-trimethylhexanoyl peroxide (114 ° C), lauroyl peroxide (116 ° C), benzoyl peroxide (130 ° C).
C), p-chlorobenzoyl peroxide (132
C)), 2,4,4-trimethylpentyl-2-hydroperoxide (190
° C), di-i-propylbenzene halide drop (252 ° C), t-butyl hydroperoxide (255 ° C), cumene hydroperoxide (264).
° C), tris- (t-butylperoxy) triazine (174 ° C), dicumyl peroxide (179 ° C), 2,5-dimethyl-2,5-
G (t-butylperoxy) -hexane (181
C), 1,3-bis- (t-butylperoxy-i-propyl) -benzene (183C), t-butylcumyl peroxide (183C), di-t-butylperoxide (192C), 2,5-dimethyl-2,5-di-
(T-butylperoxy) -hexyne-3 (193 ° C.)
Dialkyl peroxides such as 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane (152 ° C.), 1,1-di-t-butylperoxycyclohexane (156 ° C.), 2-di- (t-butylperoxy) -butane (161 ° C.), 2,2-bis-
(4,4-di-t-butylperoxycyclohexyl)
A peroxyketal such as propane (181 ° C.), α-
Cumyl peroxy neodecanoate (86 ° C), 2,
4,4-trimethylpentyl peroxy neodecanoate (91 ° C.), 2,4,4-trimethyl pentyl peroxyphenoxy acetate (96 ° C.), t-butyl peroxy neodecanoate (99 ° C.), t- Butyl peroxy neohexipivalate (112 ° C), 2,4,4-trimethylpentylperoxy-2-ethylhexanoate (124 ° C), t-amyl peroxy-2-ethylhexanoate (127 ° C) , T-butyl peroxy-2
-Ethylhexanoate (133 ° C), t-butylperoxy-i-butylate (133 ° C), di-t-butylperoxyhexahydroterephthalate (142 ° C),
Di-t-butyl peroxyazelate (157 ° C.), t
Alkyl peresters such as -butylperoxy-3,5,5-trimethylhexoate (159 ° C), t-butylperoxyacetate (163 ° C) and t-butylperoxytrimethyladipate (169 ° C); 3-
Methoxybutyl peroxydicarbonate (85 ° C),
Bis (4-di-t-butylcyclohexyl) peroxydicarbonate (92 ° C), di-i-propylperoxydicarbonate (93 ° C), t-butylperoxy-
and percarbonate such as i-propyl carbonate (156 ° C.).

Of these organic peroxides, when the heat treatment described below is carried out at a temperature at which the propylene-based random copolymer maintains the particle shape, that is, at a temperature lower than the melting point of the copolymer, One-minute half-life temperature of 80 to 150
The organic peroxide of 80 degreeC is preferable, and the organic peroxide of 80-120 degreeC is especially preferable. It is also an aspect of the present invention that the same heat treatment is performed at a temperature at which the copolymer is in a molten state. In this case, the one-minute half-life temperature is 150 to 270 ° C. Organic peroxides are preferred, especially 1
Organic peroxides at 50-250 ° C are preferred.

In the method of the present invention, first, an organic peroxide is added to and mixed with the propylene random copolymer described above. The mixing ratio of the propylene random copolymer 1
The organic peroxide is 0.001 to 1 part by weight relative to 00 parts by weight, more preferably the propylene random copolymer 1
0.005 to 0.5 parts by weight of organic peroxide per 100 parts by weight, most preferably propylene random copolymer 10
The amount of the organic peroxide is 0.005 to 0.25 parts by weight based on 0 parts by weight. In addition, when the propylene random copolymer uses a linear aliphatic polyene as the polyene, a gel is easily generated in the obtained modified propylene random copolymer. Is 0.003 to 0.2 parts by weight of an organic peroxide per 100 parts by weight of a propylene-based random copolymer, and most preferably 0.003 to 0.2 parts by weight of an organic peroxide per 100 parts by weight of a propylene-based random copolymer. 08 parts by weight. If the addition ratio of the organic peroxide is small, the melt tension of the modified propylene random copolymer obtained is insufficiently improved, and if the addition ratio of the organic peroxide is too large, the modified propylene random copolymer obtained is too large. The polymers now include gels, both of which are outside the scope of the present invention.

When adding and mixing the organic peroxide to the modified propylene-based random copolymer, toluene, xylene, isoparaffin,
It is also possible to use those diluted with an inert medium represented by a hydrocarbon solvent such as octane or decane or an inorganic substance such as calcium carbonate. The concentration of organic peroxide in the medium is 1
Those having about 0% by weight or more are used.

The addition and mixing of the organic peroxide to the propylene-based random copolymer is usually carried out by a known method. For example, it can be carried out using a stirring and mixing device such as a Henssel mixer (trade name) and a super mixer. The temperature during the addition and mixing is desirably 40 ° C or lower and 0 ° C or higher.

In the present invention, the mixture of the propylene-based random copolymer and the organic peroxide is subsequently added in an amount of from 80 to 3%.
Heat treatment at 50 ° C. Various modes are possible as the heat treatment in the present invention, and are not particularly limited, but the following modes are more preferable. The first is a heat treatment under a temperature condition in which the propylene-based random copolymer maintains the particle shape,
The second is a heat treatment under a temperature condition at which the propylene-based random copolymer becomes a molten state. It is also one of the preferred embodiments of the present invention to combine the second embodiment after the first embodiment. Particularly preferred is the second embodiment.

In the first embodiment, the heat treatment performed under the temperature condition that the propylene random copolymer keeps the particle shape is 80 ° C. or more and the melting point of the propylene random copolymer or less. More preferably 80 to 15
It is carried out at 0 ° C., particularly preferably at 80 to 140 ° C.
The heat treatment time is from 5 minutes to 5 hours, preferably from 10 minutes to 3 hours. The heat treatment is preferably performed in an inert gas atmosphere.

In the second embodiment, the heat treatment performed under the temperature condition at which the propylene random copolymer according to the present invention is in a molten state is not less than the melting point of the propylene random copolymer and not more than 350 ° C. Temperature, more preferably 190 to 300 ° C, particularly preferably 200 to 280
Performed at ° C. For the heat treatment, a method using a melt kneader is simple, and a known ordinary melt kneader is used as the melt kneader. For example, single screw extruder, twin screw extruder,
Extruders, Brabenders, Banbury mixers, etc. combining these with a gear pump. The melt-kneading time varies depending on the melt-kneader and is not specified, but usually about 20 seconds to 30 minutes is sufficient. Usually, after melt-kneading, it is subsequently cut into granules and pelletized.

In the case of melt kneading, an antioxidant, an ultraviolet absorber, an antistatic agent, a nucleating agent, a lubricant, a flame retardant, an antiblocking agent, a colorant, an inorganic or organic Various additives such as a filler can be blended.

The modified propylene-based random copolymer obtained by the production method of the present invention can be obtained by the above method. To achieve the object of the present invention, the modified propylene-based random copolymer is prepared by the method described above (MS ) And [η] must have two characteristic requirements. In other words, even within the range of the above production method, the obtained modified propylene-based random copolymer necessarily has two characteristic requirements,
Therefore, the appropriate combination of the amount of the organic peroxide and the heat treatment conditions according to the combination of the types of the propylene random copolymer and the organic peroxide to be used is determined in the production conditions of the present invention described above. You need to choose from.

Thus, the modified propylene random copolymer obtained by the method of the present invention has an extremely high melt tension and excellent moldability, and can be used again as a molded article and then re-melted for recycling. Therefore, particularly suitable for hollow molding, foam molding, extrusion molding, but not limited to the molding field, by injection molding, T-die molding, thermoforming, etc., various containers such as hollow containers, films, sheets, It can be used for various molded products such as pipes and fibers.

[0043]

Next, the present invention will be described specifically with reference to examples. Definitions of terms used in Examples and Comparative Examples and measurement methods are as follows. (1) Polyene content: Measured using ¹³ C-NMR. (Unit: mol%) (2) Intrinsic viscosity: [η], measured by the method described above.
(Unit: dl / g) (3) Melt tension: (MS), measured by the method described above. (Unit: gf)

Example 1 A magnesium chloride-supported titanium catalyst component and triethylaluminum obtained by the method described in Example 1 of JP-A-62-104812 were mixed with the titanium catalyst component and triethylaluminum in the titanium catalyst component. 200 moles per mole of titanium and diisopropyldimethoxysilane as the third component
Using a catalyst combining 20 moles per mole, n-
An intrinsic viscosity [η] obtained by slurry polymerization of propylene and 7-methyl-1,6-octadiene in hexane in the presence of hydrogen as a molecular weight controlling agent has an intrinsic viscosity [η] of 2.94 dl /
g, 7-methyl-1,6-octadiene content is 3.1.
A propylene-7-methyl-1,6-octadiene random copolymer powder having an average particle diameter of 450 μm and a mole percentage of 1% was used as the propylene random copolymer used in the present invention.
0 kg, and 2,5-dimethyl- as an organic peroxide.
2,5-di- (t-butylperoxy) -hexane 12
g, and tetrakis [methylene-3-
(3′-5′-di-t-butyl-4′-hydroxyphenyl) propionate] 10 g of methane and 10 g of calcium stearate were charged into a Hensel mixer (trade name) having an internal volume of 801. Subsequently, the mixture was stirred and mixed at 25 ° C. for 2 minutes. Further, the mixture was melt-kneaded at 230 ° C. using an extrusion granulator having a screw diameter of 40 mm to obtain pellets of the modified propylene-based random copolymer of the present invention.

Examples 2 and 3 and Comparative Examples 1 to 4 In Example 1, the content and intrinsic viscosity of 7-methyl-1,6-octadiene of the propylene-based random copolymer used as the raw material, and the organic peroxide The pellets were obtained in the same manner as in Example 1 except that the amount of 2,5-dimethyl-2,5-di- (t-butylperoxy) -hexane was changed as shown in Table 1. Was.

Examples 1 to 3 and Comparative Examples 1 to 4
Table 1 shows the conditions and results.

[0047]

[Table 1]

Example 4 In Example 1, propylene containing 0.84 mol% of 1,9-decadiene instead of 7-methyl-1,6-octadiene and having an intrinsic viscosity [η] of 1.77 dl / g was used. 1-g dicumyl peroxide instead of 2,5-dimethyl-2,5-di- (t-butylperoxy) -hexane as an organic peroxide
Pellets were obtained in the same manner as in Example 1, except that they were used and the melt-kneading temperature was set to 220 ° C.

Comparative Examples 5 and 6 Pellets were obtained in the same manner as in Example 4 except that the amount of dicumyl peroxide was changed to the amount shown in Table 2.

Comparative Example 7 In Example 4, a propylene homopolymer was used in place of the propylene random copolymer used as a raw material.
Pellets were obtained in the same manner as in Example 4, except that the other conditions were changed as shown in Table 2.

Example 5 In Example 1, the propylene random copolymer used as a raw material had an intrinsic viscosity [η] of 2.73 dl /
g, 7-methyl-1,6-octadiene content is 1.3.
Example 1 except that a propylene-7-methyl-1,6-octadiene-1-butene random copolymer powder having 5 mol% and a 1-butene content of 0.5 mol% was used.
A pellet was obtained in the same manner as described above.

Table 2 shows the conditions and results of Examples 4 and 5 and Comparative Examples 5 to 7 described above.

[0053]

[Table 2]

Use Example 1 0.1 part by weight of talc as a foam nucleating agent was added to 100 parts by weight of a mixture of a propylene-based random copolymer, an organic peroxide and an additive obtained in the same manner as in Example 1. And the mixture was fed to a single screw extruder set to a screw diameter of 65 mm and an extruder temperature of 230 ° C. Then, 22 parts by weight of 1,1,2,2-tetrafluorodichloroethane was injected as a foaming agent in the middle of the extruder. Extrusion foam molding was performed at a mold temperature of 155 ° C. using a nozzle-shaped mold having a diameter of 5 mm attached to the extruder. The surface of the obtained foam was smooth, and no abnormal air bubbles were observed, and the foam had uniform air bubbles.

Comparative Use Example 1 Extrusion foaming was carried out in the same manner as in Use Example 1 except that no organic peroxide was added, and the resulting foam had outgassing and was poor in appearance. Moreover, there was a large nest, which was unsatisfactory and could not be used.

Use Example 2 Extrusion sheeting of the modified propylene-based random copolymer pellets obtained in the same manner as in Example 1 was performed at 260 ° C. using an extruder having a T-die and a screw diameter of 65 mm. Then, a sheet having a thickness of 0.5 mm was obtained. Next, in order to modelly evaluate the heat vacuum formability of the sheet,
The sheet was fixed in a 40 cm square frame, placed in a constant temperature room at 210 ° C., and observed for behavior. The center of the sheet began to hang down due to the heating, and when the sheet hanged down by 35 mm, the hang was stopped and, conversely, the hang down was raised. When 12 seconds had elapsed after the suspension of the drooping, the sheet began to droop again, and thereafter only drooped. The amount of droop was small and the time until the start of re-droop was as long as 12 seconds, indicating that the sheet was extremely excellent in heat vacuum formability.

Comparative Use Example 2 The same procedure as in Use Example 2 was carried out except that the pellets obtained in the same manner as in Comparative Example 1 were used instead of the modified propylene random copolymer pellets obtained by the method of the present invention. To obtain a sheet. When the heating behavior of the sheet was observed in the same manner as in Example 9, the sheet stopped drooping at 40 mm, and the time until the start of re-droop was as short as 5 seconds. The heat vacuum formability was poor.

Use Example 3 A modified propylene random copolymer pellet obtained in the same manner as in Example 1 was used at a molding temperature of 230 ° C. and a mold temperature of 20 ° C. using a direct blow molding machine having a screw diameter of 65 mm. When a kerosene tank having an inner volume of 100 l was blow-molded, a homogeneous blow-molded product with no unevenness in thickness was obtained without drawdown of the parison. Subsequently, the hollow molded product was pulverized into a pulverized product. A propylene random copolymer composition comprising 10% by weight of the thus obtained molded product and 90% by weight of a modified propylene random copolymer pellet obtained in the same manner as in Example 1 was used. When a kerosene tank having an inner volume of 100 l was hollow-molded in the same manner as described above, a homogeneous hollow molded article having a parison without drawdown and without unevenness in thickness was obtained.

[0059]

As is clear from the above-described embodiment,
The modified propylene-based random copolymer of the present invention has an extremely high melt tension and excellent moldability, and can be used in a wide range of applications limited by conventional polypropylene.

Claims (1)

(57) [Claims] 1. The propylene content is 99.9 to 70 mol%, the polyene content is 0.1 to 10 mol%, and the olefin content of 2 to 12 carbon atoms other than propylene is 0 to 20 mol%. To 100 parts by weight of the propylene-based random copolymer, 0.001 to 1 part by weight of an organic peroxide was added and mixed.
(A) The melt tension (MS) at 230 ° C. and the intrinsic viscosity [η] measured in tetralin at 135 ° C. are logarithmic.
(MS)> 4.24 * log [η] −0.915, and (B) a modified propylene-based random having a boiling xylene extraction residual ratio of 1% by weight or less. A method for producing a copolymer.