JPH0931299A - Propylene polymer composition and its production - Google Patents

Abstract

PURPOSE: To obtain a propylene polymer composition that excels in mechanical properties, such as rigidity and surface hardness as well as impact resistance. CONSTITUTION: This composition is a propylene polymer composition having a melt flow rate of 0.3-50g/10min., which is substantially composed of an ethylene-propylene block copolymer component having 0.3-10wt.% in ethylene content and a high-molecular-weight propylene polymer component whose isotactic pentad fraction is >=0.90, and in the entire composition, the rate of polymers whose molecular weight is >=5,000,000 is 1-10wt.%, the rate of polymers whose molecular weight is <=10,000, is <=10wt.%.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel polypropylene polymer composition. More specifically, the present invention provides a propylene polymer composition and a method for producing the same, which provides a molded product having significantly improved mechanical properties such as rigidity and surface hardness while maintaining the excellent impact resistance of ethylene-propylene block copolymer. To do.

[0002]

2. Description of the Related Art Ethylene-propylene block copolymers have excellent impact resistance and are used for automobile exteriors, interior applications, container containers and the like. However, there is a defect that rigidity and surface hardness are poor, and improvement is desired.

Conventionally, various methods have been used to improve the rigidity and surface hardness of such ethylene-propylene block copolymers.

For example, there may be mentioned (1) a composition obtained by mixing an ethylene-propylene block copolymer with an inorganic filler. Examples of the inorganic filler include talc, mica, glass fiber, calcium carbonate and the like.

Further, (2) a composition obtained by adding a crystallization nucleating agent to an ethylene-propylene block copolymer can be mentioned. Examples of the crystallization nucleating agent include aluminum benzoate, sodium organic phosphate, and sorbitol derivative.

Further, a composition is known in which (3) an ethylene-propylene block copolymer is mixed with a propylene homopolymer having a usual molecular weight.

Further, (4) as proposed in Japanese Patent Publication No. 4-6725, obtained by a multi-stage polymerization method in which four or more ethylene-propylene block copolymers are connected in series. A composition is mentioned. That is,
In such a composition, at this time, propylene is continuously polymerized in 3 or more of 4 or more polymerization tanks connected in series, and then ethylene-propylene random copolymer is added in the 4th or subsequent polymerization tanks. Obtained by doing.

[0008]

However, although the composition of the above (1) is improved in rigidity by mixing with the inorganic filler, it is one of the features of the ethylene-propylene block copolymer, that is, lightweight. Properties are impaired and impact resistance is reduced. Mixing with metallic fillers has similar drawbacks.

Further, in the composition (2), the drawbacks of incorporating a crystallization nucleating agent are a decrease in impact resistance and an increase in molding shrinkage.

Further, in the composition (3), when a mixture with a propylene homopolymer having a usual molecular weight is used, the improvement in rigidity is achieved, but the impact resistance is lowered. Further, a mixture with a relatively high molecular weight propylene homopolymer, although it is possible to improve the rigidity while maintaining impact resistance, the mixing with the ethylene-propylene block copolymer is not uniform,
Poor appearance due to flow marks and spots. In addition, defects similar to voids may occur due to improper mixing, in which case the impact resistance is greatly reduced.

Further, according to the above (4), an ethylene-propylene block copolymer having excellent rigidity and heat resistance and good impact resistance can be obtained, but it is possible to obtain propylene in a polymerization tank connected in series. Since multi-stage polymerization is performed, it is difficult to make a large difference in the molecular weight of the propylene polymer produced in each stage. Therefore, it is difficult to obtain a high molecular weight polymer involved in the improvement of rigidity and surface hardness, and a polymer having a suitable ratio of the fluidity-related polymer, and a low molecular weight polymer produced by multistage polymerization. The ratio is high, and the improvement of the surface hardness is insufficient.

[0012] Therefore, an object of the present invention is to provide a molding material in which the excellent impact resistance originally possessed by the ethylene-propylene block polymer is maintained or further improved and the rigidity and the surface hardness are improved.

[0013]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that a composition obtained by blending an ethylene-propylene block copolymer with a high-molecular-weight propylene polymer having specific characteristics is found. It was found that a composition which can maintain or further improve the excellent impact resistance originally possessed by the ethylene-propylene block copolymer, and which is excellent in the effect of improving rigidity and surface hardness, completes the present invention. Came to.

That is, the present invention has an ethylene content of 0.3 to
10% by weight of an ethylene-propylene block copolymer component and a high-molecular-weight propylene polymer component having an isotactic pentad fraction of 0.90 or more are substantially formed, and in the entire composition, a weight-average molecular weight of 5,000,000 or more is obtained. A propylene polymer composition, characterized in that the proportion of coalesced is 1 to 10% by weight, the proportion of a polymer having a molecular weight of 10,000 or less is 10% by weight or less, and the melt flow rate is 0.3 to 50 g / 10 minutes. is there.

The propylene polymer composition of the present invention comprises an ethylene-propylene block copolymer component having an ethylene content of 0.3 to 10% by weight and a high molecular weight having an isotactic pentad fraction of 0.90 or more. It consists of a propylene polymer component.

In the present invention, the ethylene-propylene block copolymer component is a nuclear magnetic resonance spectrometer (hereinafter NM).
Ethylene content measured by R) is 0.3-10 wt%
And preferably composed of 0.5 to 8% by weight of ethylene-propylene block copolymer. When the ethylene content is less than 0.3% by weight, the molded article of the propylene polymer composition is inferior in impact resistance, and when it exceeds 10% by weight, a propylene polymer composition giving a molded article excellent in rigidity and surface hardness. I can't get things.

The ethylene-propylene block copolymer having an ethylene content of 0.3 to 10% by weight may be one produced by any known method. Generally, it can be produced by various polymerization methods using a Ziegler-type polymerization catalyst and its improved catalyst. Specifically, as a catalyst, a conventionally known titanium compound and an organoaluminum compound can be used in combination, and if necessary, various esters, ethers, and electron donors such as organosilicon compounds. It can also be combined. The polymerization mode may be continuous or batch type, and may be solution polymerization performed in a solution of heptane or the like, slurry polymerization using propylene itself as a solvent, or gas phase polymerization. Polymerization is usually carried out by supplying propylene, ethylene and hydrogen within a temperature range of 0 ° C. to 100 ° C., and after the predetermined polymerization is completed, the polymerization is stopped with isopropyl alcohol or the like. The polymerization apparatus is an apparatus for sequentially polymerizing an ethylene-propylene random copolymer and a propylene polymer in one polymerization tank, or an apparatus in which two or more polymerization tanks are connected in series. After polymerizing the random copolymer, the catalyst retaining activity and ethylene-propylene random copolymer are transferred to the next polymerization tank,
There is no particular limitation on the device for continuously polymerizing the propylene polymer.

In the present invention, the high molecular weight propylene polymer component is composed of a high molecular weight propylene polymer having an isotactic pentad fraction measured by NMR of 0.90 or more, preferably 0.93 or more. . When the isotactic pentad fraction of the high molecular weight propylene polymer is less than 0.90, it is not possible to obtain a propylene polymer composition which gives a molded product having high rigidity and surface hardness.

The above-mentioned high-molecular-weight propylene polymer is preferably a propylene homopolymer, but 1% by weight or less may contain other α-olefin as a copolymerization component. Examples of such other α-olefins include:
Examples thereof include ethylene, 1-butene, 1-pentene, 1-hexene and the like. The copolymer, propylene-ethylene random copolymer, binary random copolymer such as propylene-1-butene random copolymer, ternary random copolymer such as ethylene-propylene-1-butene random copolymer Examples include coalescing.

The high molecular weight propylene polymer used in the present invention may be obtained by any method, but it is preferable to polymerize propylene in the presence of a titanium compound and an organoaluminum compound.

As the above titanium compound, compounds known to be used for the polymerization of α-olefin can be used without any limitation. Among them, a titanium compound having titanium, magnesium and halogen and having a high catalytic activity is preferable, and a titanium halide, particularly titanium tetrachloride supported on various magnesium compounds is particularly preferable.

As the above-mentioned organoaluminum compound, compounds known to be used for the polymerization of olefins can be adopted without any limitation.

In the above-mentioned production method, ether, amine, amide, sulfur-containing compound, nitrile, carboxylic acid, acid amide, acid anhydride are used for further improving the isotactic pentad fraction of the high molecular weight propylene polymer obtained. It is preferable to use an electron donor such as an acid ester or an alkoxysilicon compound, and among them, an alkoxysilicon compound is particularly preferable.

The propylene polymer composition of the present invention was measured by gel permeation chromatography (hereinafter also referred to as GPC) in the total composition consisting of the ethylene-propylene block copolymer component and the high molecular weight propylene polymerization component. It is important that the proportion of the polymer having a molecular weight of 5,000,000 or more is 1 to 10% by weight, preferably 1.1 to 8% by weight. That is, when the proportion of the polymer having a molecular weight of 5,000,000 or more is less than 1% by weight, the effects of improving the rigidity, surface hardness, impact resistance and the like of the molded article obtained from the propylene polymer composition are not sufficient, and the present invention Can not achieve the purpose of. Also, the molecular weight is 500000
If the proportion of the polymer of 0 or more exceeds 10% by weight, the molded product obtained from the propylene polymer composition will have poor appearance such as flow marks and lumps, and the fluidity at the time of molding will also decrease.

The proportion of the polymer having a molecular weight of 5,000,000 or more can be adjusted mainly by the weight average molecular weight, the molecular weight distribution and the blending amount of the high molecular weight propylene polymer.

Further, the propylene polymer composition is GPC
It is important that the proportion of the propylene polymer having a molecular weight of 10,000 or less as measured by 1. is 10% by weight or less, preferably 8% by weight or less. That is, when the proportion of the polymer having a molecular weight of 10,000 or less exceeds 10% by weight, not only the surface hardness of the molded product of the propylene polymer composition is lowered and the scratch resistance is lowered, but also the impact resistance of the resulting molded product is lowered. Mechanical properties such as are also deteriorated.

The proportion of the polymer having a molecular weight of 10,000 or less varies depending on the amount of the low molecular weight component derived from the high molecular weight propylene polymer and the ethylene-propylene block copolymer. Most preferably, low molecular weight high molecular weight propylene polymers and ethylene-propylene block copolymers are used.

The composition containing a low molecular weight component exceeding the above range is obtained by washing and removing the low molecular weight component with an appropriate solvent, for example, a hydrocarbon solvent such as n-hexane or n-butane. Although it is possible to use the above composition, it tends to elute the copolymerized portion of the ethylene-propylene block copolymer, resulting in a decrease in impact resistance.

Further, the propylene polymer composition of the present invention has a melt flow rate of 0.3 to 50 g / 10 minutes, preferably 0.5 to 40 g / 10 minutes. When the melt flow rate is less than 0.3 g / 10 minutes, the fluidity is low, and it is difficult to injection-mold a molded product, especially a large molded product.
When it exceeds 50 g / 10 minutes, it becomes difficult to obtain a propylene polymer composition which gives a molded article excellent in surface hardness and impact resistance.

The melt flow rate is controlled by adjusting the weight average molecular weight of the constituent ethylene-propylene block copolymer and the high molecular weight propylene polymer, Mw / M.
It can be performed by changing n and its mixing ratio.

The method for producing the propylene polymer composition of the present invention is not particularly limited, but the most preferable method is as follows. The ethylene content is 0.3 to 10% by weight, the weight average molecular weight is 100,000 to 800,000, and An ethylene-propylene block copolymer having Mw / Mn of 2 to 10, and an isotactic pentad fraction of 0.90 or more,
Weight average molecular weight is 1,000,000 or more, Mw / Mn is 1
A method of mixing with a high molecular weight propylene polymer in which the proportion of the polymer having a molecular weight of 0 to 60 and the molecular weight of 5,000,000 or more is 3% by weight or more, and the proportion of the polymer having a molecular weight of 10,000 or less is 10% by weight or less.

The ethylene-propylene block copolymer used in the present invention has an ethylene content of 0.3 as described above.
10 to 10% by weight and a weight average molecular weight of 1000
00-800000, preferably 120000-700
000 and Mw / Mn of 2 to 10, preferably 4
~ 8 are used.

When the weight average molecular weight of the ethylene-propylene block copolymer is higher than 800,000,
The resulting propylene polymer composition has low fluidity,
It becomes difficult to use it for the purpose of obtaining a molded product, especially a large molded product by injection molding. On the other hand, when the weight average molecular weight of the ethylene-propylene block copolymer is less than 100,000, the amount of the low molecular weight polymer in the obtained propylene polymer composition increases, and the amount of the polymer having a molecular weight of 10,000 or less increases. The effect of improving the impact resistance and surface hardness of the molded article obtained by using the propylene polymer composition cannot be obtained.

Further, ethylene-propylene block copolymers having an Mw / Mn of less than 2 are not only difficult to produce, but also have poor compatibility when mixed with high molecular weight polypropylene, resulting in an effect of improving the surface height. Can't get enough. On the other hand, when the Mw / Mn of the ethylene-propylene block copolymer exceeds 10, the amount of the low molecular weight polymer in the obtained propylene polymer composition increases and the amount of the polymer having a molecular weight of 10,000 or less increases. However, the effect of improving the impact resistance and surface hardness of the molded product obtained by using the propylene polymer composition cannot be sufficiently obtained.

The melt flow rate of the ethylene-propylene block copolymer is 0.3 to 60 g / 10 minutes,
It is particularly preferably in the range of 0.5 to 50 g / 10 minutes.

The high molecular weight propylene polymer used in the present invention has an isotactic pentad fraction of 0.90.
In addition to the above, the weight average molecular weight is 1,000,000 or more, preferably 1100000 or more, and Mw / Mn is 10
To 60, more preferably 12 to 50, and the proportion of the polymer having a molecular weight of 5,000,000 or more is 3% by weight or more,
It is preferably 4 to 15% by weight and has a molecular weight of 10,000.
The following polymer is used in an amount of 10% by weight or less, preferably 8% by weight or less.

That is, when the weight average molecular weight of the high molecular weight propylene polymer is less than 1,000,000, it is difficult to adjust the proportion of the polymer having a molecular weight of 5,000,000 or more in the obtained propylene polymer composition within the above range. It becomes difficult to sufficiently exert the effects of improving the rigidity and surface hardness of the molded product obtained from the polymer composition. Although the upper limit of the weight average molecular weight of the high molecular weight polypropylene polymer is not particularly limited, it is generally 4,000,000.
It is about 3,000,000, particularly preferably 3,000,000.

Further, Mw / of the high molecular weight propylene polymer
When Mn is less than 10, the compatibility in mixing with the ethylene-propylene block copolymer is not sufficient, and the effect of improving rigidity is insufficient in the molded product obtained from the propylene polymer composition, and the molded product is also insufficient. The appearance defects such as flow marks and spots occur.

On the other hand, if Mw / Mn exceeds 60, the proportion of the polymer having a low molecular weight becomes too large, and the amount of the polymer having a molecular weight of 10,000 or less increases in the obtained propylene polymer composition. The effect of improving the impact resistance and surface hardness of the resulting molded article cannot be sufficiently obtained.

In the above high molecular weight propylene polymer,
When the amount of the polymer having a molecular weight of 5,000,000 or more is less than 3% by weight, the rigidity and surface hardness of the molded product of the propylene polymer composition are not sufficiently improved. The molecular weight of 50,000
If the amount of the polymer of 00 or more is too large, defective appearance such as flow marks and spots is likely to occur in the molded product. Therefore, it is preferable to use a polymer in the above preferable range.

In the above-mentioned high molecular weight propylene polymer, when the polymer having a molecular weight of 10,000 or less exceeds 10% by weight, the surface hardness of the obtained propylene polymer composition molded article decreases.

As a preferred embodiment of the above-mentioned high-molecular-weight propylene polymer, the shape of the molecular weight distribution curve measured by GPC does not show the shape of two or more peaks that can be clearly discriminated. It is preferable to reduce the amount. Here, the molecular weight distribution curve exhibits two or more peaks that can be clearly distinguished, in which a horizontal axis represents a molecular weight represented by a common logarithm and a vertical axis represents an elution amount of a propylene polymer. It means that a valley portion having a height of 0.8 times or less of the height of another peak is present between the other adjacent or smaller peaks.

The melt flow rate of the high molecular weight propylene polymer is 0.01 to 1 g / 10 minutes, preferably 0.05 to 0.8 g / 10 minutes. It is preferable in order to prevent generation of seeds and to sufficiently improve rigidity and surface hardness.

In the above-mentioned method for producing a high-molecular-weight propylene polymer, as a method for obtaining a polymer having the above-mentioned properties, known methods can be adopted without particular limitation.

For example, a molecular weight modifier can be used during the polymerization. An example of a molecular weight regulator is hydrogen.
The method for adding the molecular weight modifier is, at the initiation of the polymerization of the polypropylene of the present invention, or at the initiation of the polymerization of the low molecular weight polypropylene, a method of adding the entire amount at once, a method of gradually adding it within a certain period of time, or There is no particular limitation such as a method of increasing the amount of addition stepwise at regular intervals, and the amount of addition is preferably within the range where the hydrogen concentration in the gas phase is 0 to 60 mol%.

Polymerization of the high-molecular-weight propylene polymer can be carried out batchwise or continuously in one polymerization vessel or in two or more polymerization vessels connected in series. It is preferable that the propylene polymer having a relatively high molecular weight and the propylene polymer having a relatively low molecular weight have a large difference in molecular weight.

For the polymerization of the high molecular weight propylene polymer, slurry polymerization, bulk polymerization, gas phase polymerization or the like can be used without any limitation.

The polymerization conditions are not particularly limited, and the polymerization temperature, the polymerization pressure and the polymerization time may be appropriately controlled so as to obtain the above high molecular weight propylene polymer.

The mixing ratio of the above-mentioned ethylene-propylene block copolymer and high-molecular weight polypropylene may be appropriately mixed so that the composition of the above-mentioned propylene polymer composition is obtained. In general, ethylene-propylene is used. 10 to 200 parts by weight, preferably 15 to 200 parts by weight of a high molecular weight propylene polymer, relative to 100 parts by weight of the block copolymer.
It is preferable to mix 150 parts by weight to form the propylene polymer composition of the present invention.

Any method may be used for mixing the ethylene-propylene block copolymer and the high molecular weight propylene polymer. For example, a method of blending the ethylene-propylene block copolymer and the high-molecular weight propylene polymer with a Henschel mixer or the like, a method of melt-kneading with an extruder, a method of directly forming a polymerization composition in a polymerization vessel, and the like can be mentioned.

The propylene polymer composition of the present invention contains heat stabilizers, weather stabilizers, crystallization nucleating agents, fillers, pigments, lubricants, etc., which have been conventionally used, within the range that does not significantly impair the properties thereof. Additives can be added.

The propylene polymer composition of the present invention can be molded into various shapes by various molding methods such as injection molding, extrusion molding and compression molding. If it exerts a remarkable effect.

The high molecular weight polypropylene provided by the present invention, that is, the isotactic pentad fraction is 0.90 or more and the weight average molecular weight is 1000, as described above.
000 or more, Mw / Mn of 10 to 60, molecular weight of 5,000
A high-molecular-weight propylene polymer in which the proportion of the polymer of 000 or more is 3% by weight or more and the proportion of the polymer of which molecular weight is 10,000 or less is 10% by weight or less, is particularly preferable for the surface hardness of the ethylene-propylene block copolymer and It is extremely useful as a rigidity modifier.

[0054]

INDUSTRIAL APPLICABILITY The propylene polymer composition of the present invention has excellent mechanical properties such as rigidity, surface hardness and impact resistance of the obtained molded product, and is free from flow marks and spots and has good fluidity. It is something. Therefore, the propylene polymer composition of the present invention is easy to mold in a normal injection molding machine, an extrusion molding machine, and the like, mechanical strength is required for the roller, mechanical parts such as pipes and propellers, timing gears, It can be used as automobile parts such as inner panels and various housing materials.

[0055]

EXAMPLES The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

Prior to the examples, the measuring method used in the examples will be described.

(1) Ethylene content FT-NMR 270 MHz apparatus was used for measurement. The ethylene content was determined by assigning peaks according to the method described in Polymer, Volume 29 (1988), page 1848, and then using Macromolecules (Macrom).
olecules) Volume 10 (1977) p. 773.

(2) Isotactic Pentad Fraction It was measured using an FT-NMR 270 MHz apparatus. The isotactic pentad fraction is found in Macromolecules, Volume 8 (1975).
, Pp. 697, and after assigning peaks, Macromolecules (Macromolecules)
es) Calculated by the method described in Volume 6 (1973), page 925.

(3) Measurement of average molecular weight of propylene polymer The apparatus used and the measurement conditions are GPC- manufactured by Waters Corporation.
Model 150C, temperature 135 ° C., solvent ortho-dichlorobenzene, used column was TSK GMH6-HT manufactured by Tosoh Corporation, gel size 10 to 15 μm. The weight average molecular weight of 950, 2900, and 1 is used as a standard sample of molecular weight.
10,000, 50,000, 49.8 million, 2.7 million, 6.75 million, 2060
The molecular weight was calibrated using 10,000 monodisperse polystyrenes.

(4) Mw / Mn The ratio of the weight average molecular weight (Mw) measured by GPC and the number average molecular weight (Mn) was determined.

(5) Measurement of ratio of propylene polymer having molecular weight of 5,000,000 or more and molecular weight of 10,000 or less It was determined from a curve obtained by integrating a molecular weight distribution curve obtained by measurement with GPC-150C manufactured by Waters Corporation.

(6) Bending elastic modulus Using an injection molding machine with a mold clamping force of 150 tons, heating cylinder temperature of 220 ° C., 128 mm × 12.7 mm × 3.1
mm test piece was prepared, and according to ASTM: D-790, 2
The flexural modulus at 3 ° C. was measured.

(7) Surface hardness Using a tester specified by JIS: K5401, a load of 1
The pencil scratch hardness was measured on the bending test piece at 00 g.

(8) Izod impact value An injection molding machine with a mold clamping force of 150 tons was used to prepare notched test pieces at a heating cylinder temperature of 220 ° C.
It was measured at 23 ° C. according to TM: D256.

(9) Surface Impact Strength Using an injection molding machine with a mold clamping force of 150 tons, a flat plate test piece of 100 × 100 × t2 mm was prepared at a heating cylinder temperature of 220 ° C., and a tip end was manufactured according to JIS: K7211. Radius 7
The 50% breaking height with a weight of 1000 mm and a weight of 1000 g was measured. The occurrence of cracks was judged to be destruction.

(10) Heat Deformation Temperature Regarding bending test pieces, according to ASTM: D-648, 0.
The heat distortion temperature under a load of 45 MPa was measured.

(11) Flow mark The test piece used for measuring the flexural modulus was visually observed and the following three-stage evaluation was performed. ◯: Almost no flow mark is seen. Δ: Some flow marks are seen. X: Many flow marks are seen.

(12) Butts The test piece used for measuring the flexural modulus was visually observed and the following three-stage evaluation was performed. ○: Almost no spots are seen. Δ: Some spots are seen. X: Many spots are seen.

Example 1 An ethylene-propylene block copolymer (C) was manufactured by
Tokuyama block PP (grade name: MS684S)
Was used and its ethylene content and melt flow rate are shown in Table 1. The high molecular weight propylene polymer (K) was polymerized according to the method described in Japanese Patent Application No. 6-136007. Table 2 shows the isotactic pentad fraction, the weight average molecular weight and Mw / Mn of the obtained high molecular weight propylene polymer, the proportion of the polymer having a molecular weight of 5,000,000 or more, and the proportion of the polymer having a molecular weight of 1,000 to 10,000. Next, 100 parts by weight of ethylene-propylene block copolymer and 30 parts by weight of high molecular weight propylene polymer were dry blended with a Henschel mixer and then melt-kneaded with an extruder having a heating cylinder temperature of 230 ° C. to obtain a propylene polymer composition. It was Molecular weight of propylene polymer composition 5
The proportion of polymers above 000000 and the molecular weight is 100
Table 3 shows the proportions of polymers of not more than 00 and the melt flow rate. Using this propylene polymer composition,
Injection molding was carried out for the production of bending test pieces and flat plates.
The bending elastic modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained test piece are shown in Table 3.
Table 3 shows the results of judging flow marks and spots on the bending test pieces.

Comparative Example 1 Injection-molding was carried out to prepare a bending test piece and a flat plate without mixing the ethylene-propylene block copolymer (C) in Example 1 with the high-molecular-weight propylene polymer. The bending elastic modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained test piece are shown in Table 3. Table 3 shows the results of judging flow marks and spots on the bending test pieces.

Comparative Example 2 An ethylene-propylene block copolymer (H) having the same melt flow rate as that of the propylene polymer composition in Example 1 (block PP (grade name: MS750) manufactured by Tokuyama Corp.) was used. Injection molding was carried out for the production of bending test pieces and flat plates. The bending elastic modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained test piece are shown in Table 3. Table 3 shows the results of judging flow marks and spots on the bending test pieces.

Comparative Example 3 Without using the ethylene-propylene block copolymer in Example 1, injection molding was carried out only for the high molecular weight propylene polymer (K) to prepare a bending test piece and a flat plate. The bending elastic modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained test piece are shown in Table 3. Table 3 shows the results of judging flow marks and spots on the bending test pieces.

Example 2 and Comparative Example 4 The ethylene-propylene block copolymer (C) in Example 1 is shown in Table 1. The ethylene-propylene block copolymer (B) (block PP manufactured by Tokuyama Corp. (grade name) : RS525)) or (A) (Homo PP manufactured by Tokuyama Corp. (grade name: MJ160)), but in the same manner as in Example 1 to obtain a propylene polymer composition. Flexural modulus of elasticity of the obtained propylene polymer composition, Izod impact value, surface impact strength, heat distortion temperature,
And the surface hardness is shown in Table 3. Table 3 shows the results of judging flow marks and spots on the bending test pieces.

Example 3, Comparative Example 5 The high-molecular-weight propylene polymer (K) in Example 1 was replaced with the high-molecular-weight propylene polymer (M) or (L) shown in Table 2, and an ethylene-propylene block copolymer was used. 100 parts by weight and 70 parts by weight of the high molecular weight propylene composition were melt-kneaded in the same manner as in Example 1 to obtain a propylene polymer composition. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Examples 4-5, Comparative Examples 6-7 Except that the mixed composition of the ethylene-propylene block copolymer (C) and the high molecular weight propylene polymer (K) in Example 1 was changed to that shown in Table 3. A propylene polymer composition was obtained in the same manner as in Example 1. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Example 6 A propylene polymer composition was prepared in the same manner as in Example 1 except that 100 parts by weight of the ethylene-propylene block copolymer (F) and 100 parts by weight of the high molecular weight propylene polymer (O) were used. I got a thing. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Example 7 The high-molecular-weight propylene polymer (K) in Example 1 was replaced with the high-molecular-weight propylene polymer (T) shown in Table 2, and the mixed composition with an ethylene-propylene block copolymer is shown in Table 3. A propylene polymer composition was obtained in the same manner as in Example 1 except that the conditions shown were changed. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determining flow marks and spots.
It was shown to.

Examples 8 to 10 and Comparative Examples 8 to 9 Various high molecular weight propylene polymers (O) whose high molecular weight propylene polymers (K) in Example 1 are shown in Table 2
A propylene polymer composition was obtained in the same manner as in Example 1 except that (Q), (R), (N) or (P) was used. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Example 11 The ethylene-propylene block copolymer (C) used in Example 1 is shown in Table 1. Ethylene-propylene block copolymer (E) (Block PP manufactured by Tokuyama Corporation (grade name: MS835)). Instead of the above, a propylene polymer composition was obtained in the same manner as in Example 1 except that the mixed composition was changed to 15 parts by weight of a high molecular weight propylene polymer with respect to 100 parts by weight of an ethylene-propylene block copolymer. Table 3 shows the flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition.
It was shown to. Table 3 shows the results of determination of flow marks and spots.

Example 12 100 parts by weight of the ethylene-propylene block copolymer (C) used in Example 1 was mixed with 0.13 of 1,3-bis- (t-butylperoxyisopropyl) benzene as a peroxide. 03 parts by weight was added, and melt kneading was performed with an extruder at 220 ° C. to obtain an ethylene-propylene block copolymer (F) having a melt flow rate of 55 g / 10 min. A propylene polymer composition was obtained in the same manner as in Example 1 except that this ethylene-propylene block copolymer (F) was used. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Comparative Example 10 An ethylene-propylene block copolymer (D) was produced in the same manner as the ethylene-propylene block copolymer in Example 1 so that the ethylene content and melt flow rate shown in Table 1 were obtained. did. A propylene polymer composition was obtained in the same manner as in Example 1, except that the ethylene-propylene block copolymer (D) was used instead of the ethylene-propylene block copolymer (C). The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3.
Table 3 shows the results of determination of flow marks and spots.

Comparative Example 11 The same method as in Example 10 was repeated except that the amount of the peroxide used in Example 10 was 0.05 part by weight based on 100 parts by weight of the ethylene-propylene block copolymer. An ethylene-propylene block copolymer (G) having a melt flow rate of 68 g / 10 min was obtained. A propylene polymer composition was obtained in the same manner as in Example 1 except that this ethylene-propylene block copolymer (G) was used.
The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determination of flow marks and spots.

Comparative Example 12 The high molecular weight propylene polymer (K) in Example 1 was replaced with the high molecular weight propylene polymer (S) shown in Table 2, and the mixed composition with the ethylene-propylene block copolymer is shown in Table 3. A propylene polymer composition was obtained in the same manner as in Example 1 except that the conditions shown were changed. The flexural modulus, Izod impact value, surface impact strength, heat distortion temperature, and surface hardness of the obtained propylene polymer composition are shown in Table 3. Table 3 shows the results of determining flow marks and spots.
It was shown to.

[0084]

[Table 1]

[0085]

[Table 2]

[0086]

[Table 3]

Claims (3)

[Claims] 1. An ethylene-propylene block copolymer component having an ethylene content of 0.3 to 10% by weight, and a high molecular weight propylene polymer component having an isotactic pentad fraction of 0.90 or more, In all compositions, the proportion of polymers having a molecular weight of 5,000,000 or more is 1 to 10% by weight, and the proportion of polymers having a molecular weight of 10,000 or less is 10% by weight.
The melt flow rate is 0.3 to 50 g / 10 or less
Is a propylene polymer composition. 2. An ethylene content of 0.3 to 10% by weight, a weight average molecular weight of 100,000 to 800,000, and a ratio (M) of the weight average molecular weight (Mw) to the number average molecular weight (Mn).
w / Mn) of 2 to 10 and an ethylene-propylene block copolymer, an isotactic pentad fraction of 0.90 or more, a weight average molecular weight of 1,000,000 or more,
The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) is 10 to 60, the ratio of the polymer having a molecular weight of 5,000,000 or more is 3% by weight or more, and the molecular weight is 10
The method for producing a propylene polymer composition according to claim 1, wherein a high molecular weight propylene polymer in which the proportion of the polymer of 000 or less is 10% by weight or less is mixed. 3. The isotactic pentad fraction is 0.9.
0 or more, weight average molecular weight 1,000,000 or more, ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw /
A surface hardness modifier comprising a high molecular weight propylene polymer having a Mn) of 10 to 60, a polymer having a molecular weight of 5,000,000 or more in a proportion of 3% by weight or more, and a polymer having a molecular weight of 10,000 or less in a proportion of 10% by weight or less.