JPH0848834A - Polypropylene resin composition and oriented polypropylene film - Google Patents

Abstract

PURPOSE:To obtain a polypropylene resin composition having improved transparency and printability and good processability without problems, in forming an oriented film therefrom, such as sheet edge roughness during raw sheet extrusion, sheet breakage in drawing, and draw unevenness and/or breakage, and to obtain a polypropylene drawn film from the composition. CONSTITUTION:This polypropylene resin composition comprises crystalline polypropylene, 0.1-1,000ppm of a cyclic olefin polymer, e.g. polycyclodentene, polycyclobutene, and 50-4,000ppm of talc with an average particle diameter of 0.1-10mum. The other objective polypropylene film oriented at least uniaxially is obtained from the above resin composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene resin composition and a stretched film comprising the polypropylene resin composition. More specifically, the crystalline polypropylene is made to contain a small amount of a cyclic olefin polymer and talc, and transparency and image clarity are remarkably improved, and at the time of molding of a uniaxially or biaxially stretched film, when a raw sheet is extruded. Polypropylene resin suitable for stretched film that does not cause edge roughening of the sheet, breaks the stretched sheet during longitudinal stretching, does not cause deterioration of thickness accuracy due to uneven stretching of the film during transverse stretching and stretch breakage, etc. The present invention relates to a composition and a stretched film comprising the polypropylene resin composition.

[0002]

2. Description of the Related Art Polypropylene stretched films, particularly polypropylene biaxially stretched films, are widely used for packaging materials and the like because of their excellent mechanical and optical properties. The manufacturing method is generally a sequential biaxial stretching method using a tenter method. However, due to the high crystallinity of polypropylene, these polypropylene stretched films are generally inferior in transparency and image clarity to other highly transparent thermoplastic resins such as polystyrene and polyvinyl chloride.

Several proposals have been made so far in an attempt to improve the transparency and image clarity of a stretched polypropylene film. For example, by adding an organic nucleating agent such as a sorbitol derivative, an alkali metal salt of an aromatic carboxylic acid or an aluminum salt to a polypropylene resin, the melted sheet is cooled during extrusion of the original sheet during film forming. It is known that upon solidification, the spherulites inside the solidified raw sheet become smaller and uniform, and the transparency and image clarity of the stretched film are improved. However, these organic nucleating agents have a problem that they bleed from polypropylene during extrusion and cause roll stains, and that odor is generated during processing. Further, there is a problem that bleeding occurs when a film or the like is stored for a long period of time. Further, in the aromatic carboxylate, there is a problem that the original performance of the additive is deteriorated or the polypropylene resin is colored by reacting with itself or its hydrolyzate with other additives. .

On the other hand, attempts have been made to improve transparency by using a copolymer of propylene and α-olefin (Japanese Patent Publication No. 32324/1985). However, it cannot be said that the image clarity is still sufficient, and when the content of α-olefin increases, the surface of the raw sheet obtained by extrusion during molding of the polypropylene stretched film becomes rough and transparent due to insufficient cooling. Property and image clarity are reduced, and wavy or saw-toothed roughness is generated at the edge of the original sheet, which causes clipping mistakes in tenter stretching and uneven stretching or stretching of the film in transverse stretching. There was a problem of tearing. further,
If the edge portion is roughened in a saw-tooth shape, the stretch breakage of the sheet occurs during the longitudinal stretching, and there is a problem in the formability of the stretched film.

Thus, conventionally, attempts have been made to improve the transparency and image clarity of the polypropylene stretched film by the above-mentioned method, but the moldability of the stretched film is still unsatisfactory. That is, the object of the present invention is to have excellent transparency and image clarity without the above-mentioned drawbacks, and at the time of forming a stretched film, does not cause edge roughness of the sheet at the time of extrusion of the original sheet, and is longitudinal. It is an object of the present invention to provide a polypropylene resin composition and a stretched film which have good moldability and do not cause stretch breakage of a sheet at the time of stretching and stretch unevenness or breakage of a film at the time of transverse stretching.

[0006]

From these viewpoints, the present inventors have made earnest studies on a polypropylene stretched film having improved transparency, image clarity, and stretched film moldability, and as a result, surprisingly, crystalline polypropylene was obtained. By a simple method of containing a small amount of cyclic olefin polymer and talc in the transparency of the polypropylene stretched film,
The inventors have found that the image clarity is remarkably improved, and that the sheet is excellent in moldability without causing edge roughness of the sheet during molding of the stretched film, and completed the present invention.

That is, the present invention relates to crystalline polypropylene,
Cyclic olefin polymer 0.1 to 1000 ppm, and talc 50 to 400 having an average particle size of 0.1 to 10 μm
A polypropylene resin composition comprising 0 ppm and a polypropylene stretched film comprising the polypropylene resin composition and stretched at least uniaxially.

Examples of the crystalline polypropylene used in the present invention include homopolymers of propylene, random copolymers of propylene and other α-olefins, and mixtures thereof. Examples of the α-olefin include ethylene, 1-butene, 1-pentene,
1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 4-methyl-1-pentene and the like can be mentioned, and the content of these α-olefins is 10 mol% or less. Are preferred for maintaining crystallinity.

The crystalline polypropylene used in the present invention is not particularly limited to the melt flow rate, but in consideration of moldability for various stretched films, it is usually in the range of 0.01 to 100 g / 10 min. What is used is, and it is preferable that it is in the range of 0.1 to 50 g / 10 min.

The crystalline polypropylene used in the present invention is crystalline and has an isotactic pentad fraction of 0.85 or more. The isotactic pentad fraction as used in the present invention means A. Zambilli et al., Macromolecules, 6 , 925 (19
23), that is, the fraction in which 5 propylene units are continuously bonded to meso as measured by ¹³ C-NMR.

The molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the crystalline polypropylene used in the present invention is not particularly limited, Considering the case of film formation, it is preferably 6 to 20 in order to increase melt tension and improve workability. The molecular weight distribution is a value measured by a gel permeation chromatography method (hereinafter, also referred to as GPC) using o-dichlorobenzene as a solvent, and a calibration curve calibrated with standard polystyrene is used.

In the present invention, the cyclic olefin polymer is a polymer of monomers having a polymerizable double bond in the ring, and known compounds can be used without any limitation as long as they are such compounds. In the present invention, the carbon number is 4
-20 homopolymers of cyclic olefin monomers, copolymers of the above cyclic olefin monomers, 50 mol% or more of the above cyclic olefin monomers and 50 m of other monomers
A copolymer with ol% or less can be preferably used. In particular, cyclobutene, cyclopentene, cyclopentadiene, 4-methylcyclopentene, 4,4 can be specifically mentioned as the cyclic olefin monomer which can be preferably used in the present invention.
-Dimethylcyclopentene, cyclohexene, 4-methylcyclohexene, 4,4-dimethylcyclohexene,
1,3-dimethylcyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, cycloheptene, 1,3-cycloheptadiene, 1,3,5-cycloheptatriene, cyclooctene, 1,5-cycloocta Diene, cyclododecene, etc. can be mentioned. Further, the ring of these cyclic olefins may be further substituted with a linear or branched alkyl group.

The cyclic olefin polymer having such stereoregularity is generally crystalline. Therefore, when the cyclic olefin polymer is measured by X-ray diffraction, a diffraction peak derived from the crystallinity of the polymer is observed. For example, the polycyclopentene used in Example 1 which will be described later is 2θ = 19.4 °, 16.0 °, 24.0 by X-ray diffraction measurement.
A diffraction peak appears at an angle of 34.5 ° with an integrated intensity of 28: 14: 2: 1. The cyclic olefin polymer in the present invention has a tendency that the higher the degree of crystallinity representing the degree of crystallinity, the higher the transparency-improving effect and the transparency-improving effect.
The crystallinity is preferably 10% or more, more preferably 30% or more, and most preferably 50% or more. As the cyclic olefin polymer having such a high crystallinity, a homopolymer of the above-mentioned cyclic olefin monomer, or a block copolymer of cyclic olefin monomers with each other or with α-olefin can be preferably used.

The polymerization method of the cyclic olefin polymer used in the present invention is not particularly limited as long as the effects of the present invention are not impaired, and for example, the following polymerization methods are used. First, the catalyst is a metallocene-based catalyst, a vanadium-based catalyst, titanium trichloride or titanium tetrachloride, which is generally composed of a metallocene compound using a transition metal of Group IV of the periodic table and a coexisting system of methylaluminoxane or alkylaluminum or alkylaluminum halide. Examples of the catalyst include a titanium-based catalyst, an anionic polymerization catalyst, a radical polymerization catalyst, and the like, each of which is supported on a magnesium compound such as magnesium chloride, and these may be used alone or in combination. Among these, preferable catalysts are metallocene catalysts, vanadium catalysts, and titanium catalysts.
The method of polymerization is not particularly limited, such as gas phase polymerization, solution polymerization and bulk polymerization.

The polymer binding mode of the cyclic olefin polymer is not particularly limited, but the cyclic olefin polymer obtained by the metallocene catalyst used in this example is S. Collin
s et al. (Scott Collins and
W. Mark Kelly, Macromolecule
es, 25 , 233 (1992)) ¹³ C-NMR
It was found to be a "cis-1,3" bond as measured by.

The content of the cyclic olefin polymer used in the present invention in the crystalline polypropylene is 0.1 to 1000.
must be in the ppm range, 0.5-500 ppm
Is more preferable, and further more preferably 1 to 200 ppm. When the content of the cyclic olefin polymer is less than 0.1 ppm, the effect of improving the transparency and image clarity is not observed. On the other hand, when it exceeds 1000 ppm, the surface of the sheet is roughened and the edges are roughened in the extrusion process of the original sheet, and the transparency of the stretched film,
Problems such as a decrease in image clarity, uneven stretching, and broken stretching occur. When a copolymer of a cyclic olefin monomer and another monomer is used as the cyclic olefin polymer, the weight of the polymerization component based on the cyclic olefin monomer needs to be within the above range. In the present invention, ppm is based on weight.

The average particle size of talc used in the present invention must be in the range of 0.1 to 10 μm, and 0.5 to
The thickness is preferably 8.0 μm, and more preferably 1.0 to 7.
It is more preferably 0 μm. If the average particle size of talc is less than 0.1 μm, talc undergoes secondary agglomeration to increase the agglomerated particle size, resulting in a decrease in transparency and fish eyes, which deteriorates the appearance of the film, which is not preferable. . On the other hand, if the average particle size exceeds 10 μm, voids are often generated during stretching of the film, and the transparency of the film decreases, which is not preferable. The method for measuring the average particle size of talc used in the present invention is not particularly limited,
A method using a Coulter counter, an electron microscope or the like is exemplified. Further, as the talc used in the present invention, known ones such as crushed products of natural products or synthetic products are used without limitation. However, considering the nucleating effect on polypropylene, the talc has high crystallinity. It is suitable.

The content of talc in the crystalline polypropylene used in the present invention must be in the range of 50 to 4000 ppm, preferably 80 to 2000 ppm, and more preferably 100 to 1000 ppm. If the talc content is less than 50 ppm,
The sufficient nucleation effect of talc cannot be obtained, and the edge of the raw sheet is roughened. On the other hand, when it exceeds 4000 ppm, the transparency of the film is lowered and the appearance is deteriorated due to the generation of voids.

The method of incorporating the cyclic olefin polymer and talc into the crystalline polypropylene is not particularly limited.
Specifically, a cyclic olefin polymer obtained by prepolymerization and talc are simultaneously added to crystalline polypropylene, and a screw extrusion kneader such as a single screw extruder or a twin screw extruder, a Banbury mixer, a continuous mixer. , A method of mixing using a mixing roll, etc., after prepolymerizing a cyclic olefin, and then adding talc after forming a crystalline polypropylene resin composition containing a cyclic olefin polymer by a block copolymerization method for main polymerization of propylene A method etc. can be mentioned.

Further, after obtaining a composition with crystalline polypropylene containing a high concentration of a cyclic olefin polymer by the method as described above, the composition is diluted with another crystalline polypropylene as a masterbatch. Magnification 2-1000
Diluted in the range of twice (the cyclic olefin polymer content is
It is possible to obtain the desired content of the cyclic olefin polymer by diluting the mixture to 0.001 times). The dilution ratio of the masterbatch is generally about 20 times, but in the present invention, the transparency and image clarity of the stretched film can be sufficiently improved even though it depends on the masterbatch concentration.

The thickness of the polypropylene stretched film of the present invention is not particularly limited, but it is usually 3 to 150 μm in the case of a biaxially stretched film and 10 to 25 in the case of a uniaxially stretched film.
It is preferably 4 μm. The polypropylene stretched film of the present invention is stretched in at least a uniaxial direction. Of course, it may be biaxially stretched. Although the stretching ratio is not particularly limited, it is generally 4 to 10 times in the uniaxial direction, and in the case of biaxial stretching, it is generally stretched in the range of 4 to 15 times in the direction perpendicular thereto. Is.

In the polypropylene resin composition and the polypropylene stretched film of the present invention, if necessary, an antioxidant, a chlorine scavenger, a heat stabilizer, an antistatic agent, an antifogging agent, an ultraviolet absorber, a lubricant, an antiblocking agent. Agents, pigments,
Additives such as other resins and fillers may be added as long as the effect is not impaired.

If necessary, one or both surfaces of the polypropylene stretched film of the present invention may be subjected to surface treatment such as corona discharge treatment. Further, for the purpose of imparting a function such as heat sealability, a layer made of another resin having a lower melting point than the crystalline polypropylene of the present invention may be laminated on one side or both sides. The method for laminating other resins is not particularly limited, but a coextrusion method, a laminating method, etc. are preferable.

As the method for producing the polypropylene stretched film of the present invention, known methods can be adopted without any limitation. For example, as a method for producing a stretched film by a sequential biaxial stretching method by a tenter method, the polypropylene resin composition is molded into a sheet or film by a T-die method, an inflation method or the like, and then supplied to a longitudinal stretching device, Longitudinal stretching 4 to 10 times at a heating roll temperature of 120 to 170 ° C., and then using a tenter, a tenter temperature of 13
A method of transversely stretching 4 to 15 times at 0 to 180 ° C. is preferable, and a method of heat treatment at 80 to 180 ° C. while allowing a relaxation of 0 to 25% in the transverse direction as needed can be mentioned. Of course, the stretching may be performed again after these stretchings, and in the longitudinal stretching, stretching methods such as multi-stage stretching and rolling can be combined. Also, a stretched film can be obtained by stretching only uniaxially.

[0025]

According to the present invention, the transparency and image clarity of a polypropylene stretched film are improved, and the surface of the sheet is not roughened or the edges are roughened in the process of forming a raw sheet when molding the stretched film. It is possible to obtain a polypropylene stretched film having excellent processability without problems such as breakage of stretching of the sheet, deterioration of thickness accuracy due to uneven stretching of the film, and breakage of stretching.

In the present invention, it is not clear why the inclusion of a small amount of talc improves the moldability of a crystalline polypropylene containing a cyclic olefin polymer into a stretched film. From the analysis results, we think as follows.

When the orientation mode of the polypropylene crystals of the crystalline polypropylene raw sheet containing the cyclic olefin polymer is analyzed in detail by the wide-angle X-ray diffraction method, the growth axis of the polypropylene crystals, that is, the a * axis is perpendicular to the sheet surface ( It was found that the orientation was strong in the sheet thickness direction). That is, while rotating the original sheet at a high speed around an axis perpendicular to the sheet surface, X
When a line is made incident and the diffraction intensity is measured, 040 reflection (2θ = 17.1 °) from the polypropylene crystal is strongly observed. Peak separation of the measured X-ray diffraction profile was performed, and 040 reflection and 111 reflection (2θ = 21.4 °)
The peak intensity ratio I (040) / I (111) of 2 is calculated to be 2 to 5, and this peak intensity ratio increases as the content of the cyclic olefin polymer increases. Z. Mencik (Z.
Mencik, Journalof Macromol
eculer Science, Physics B
6 , 101 (1972)), the peak intensity ratio is I (040) / I (111) = 1.52 when the polypropylene crystals are perfectly randomly oriented. From this,
It can be seen that in the crystalline polypropylene raw sheet containing the cyclic olefin polymer, the (040) plane of the polypropylene crystal is perpendicular to the sheet surface, that is, the b axis of the crystal is strongly oriented parallel to the sheet surface. Also, the crystal c-axis (polypropylene molecular chain axis) is oriented in the extrusion direction (parallel to the sheet surface), so the a * axis, which is the crystal growth direction, is oriented perpendicular to the sheet surface (sheet thickness direction). It turned out.

From the above, when the cyclic olefin polymer is contained in the crystalline polypropylene, the polypropylene crystals grow in the thickness direction of the sheet from the cooling roll side when the molten resin is cooled and solidified during the forming of the raw sheet. At this time, the shrinkage ratio between the cooling roll side and the surface opposite to the cooling roll, the difference in internal stress, etc. become large, so that the adhesion between the original sheet and the cooling roll deteriorates, causing uneven cooling and roll separation, It is considered that the sheet surface becomes rough and the edge condition deteriorates.

On the other hand, when talc known as an inorganic nucleating agent for polypropylene is contained, on the contrary, 040
The peak intensity ratio I (040) / I (111) between reflection and 111 reflection is 1
Below, the peak intensity ratio decreases with increasing talc content. It can be seen that in the crystalline polypropylene original sheet containing talc, the (040) plane of the polypropylene crystal is parallel to the sheet surface, that is, the b axis of the crystal is strongly oriented perpendicular to the sheet surface. Therefore, it was found that the a * axis which is the crystal growth direction is oriented in the direction parallel to the sheet surface (in the plane of the sheet). It is known that talc also has a nucleating effect on polypropylene, but in the case of talc-containing crystalline polypropylene, even if a nucleating effect such as a rise in crystallization temperature similar to that of a cyclic olefin polymer is observed, Roughness does not occur at the edge of the original sheet. This is because in the talc-containing system, polypropylene crystals grow in the sheet surface when the molten resin is cooled and solidified during the forming of the original sheet, so that there is little shrinkage or change in stress in the thickness direction. It is considered that the adhesion between the cooling roll and the cooling roll becomes good, and the state of the edge portion does not deteriorate.

Therefore, when the cyclic olefin polymer and talc are contained in the crystalline polypropylene, it is possible to control the orientation of the polypropylene crystals in the sheet, that is, the crystal growth direction, by the content and the ratio of the both. all right.

Based on the results of the above analysis, the present inventors have made talc contained in crystalline polypropylene containing a cyclic olefin polymer to allow growth of polypropylene crystals in the sheet thickness direction when forming a raw sheet. It has been found that the suppression suppresses the edge roughness of the original sheet and enables stable sheet formation. Furthermore, it is considered that the spherulites inside the original sheet are made smaller and uniform by the nucleating effect of both the cyclic olefin polymer and talc, and the transparency and image clarity of the obtained stretched film are further improved.

[0032]

EXAMPLES In order to describe the present invention more specifically, examples and comparative examples will be described below, but the present invention is not limited to these examples. The polypropylene stretched films obtained in the following examples and comparative examples were evaluated by the following methods.

(1) Haze Measured according to JIS K 6714.

(2) Image value An optical comb of 0.1 was used using an image measuring device manufactured by Suga Test Instruments Co., Ltd.
Using 25 mm, the comb direction was made parallel to the transverse stretching method of the biaxially stretched film, and the image value was measured.

Example 1 (Polymerization of cyclopentene) In a glass reactor equipped with a 2000 ml stirrer, under a nitrogen atmosphere, 500 m of toluene.
1, methylaluminoxane 500 mmol and dimethylsilylene bisindenyl zirconium dichloride 0.5
The mmol was introduced and the temperature in the system was raised to 60 ° C. The polymerization is started by adding 100 ml of cyclopentene,
Polymerization was carried out at 60 ° C. for 4 hours. The reaction mixture containing the produced solid was added to a large amount of acidic methanol to terminate the polymerization.
The obtained solid was filtered and dried under reduced pressure to obtain 63.
5 g of polycyclopentene was obtained. The crystallinity determined by X-ray diffraction was 64%.

(Granulation) 100 parts by weight of the homopolypropylene powder shown in Table 1 was mixed with 2,6-
0.1 parts by weight of di-t-butylhydroxytoluene, 0.1 parts by weight of calcium stearate as a chlorine scavenger, 100 ppm of polycyclopentene obtained above, and 300 ppm of talc having an average particle size of 4.2 μm were added. After mixing for 5 minutes with a mixer, screw diameter 65m
The raw material pellets were obtained by extruding the pellets at 230 ° C. using an mφ extrusion granulator.

(Molding of Biaxially Stretched Film) A molding experiment of a biaxially stretched film was carried out by the following method using the obtained polypropylene resin composition pellets. The polypropylene resin composition pellets were extruded at 280 ° C. using a T-die sheet extruder having a screw diameter of 90 mmφ, and a sheet having a thickness of 2 mm was formed with a cooling roll at 30 ° C. Then
This raw sheet was longitudinally stretched 4.6 times in the longitudinal direction at 150 ° C. by using a tenter type sequential biaxial stretching device, and subsequently transversely stretched 10 times in the lateral direction in a tenter at 165 ° C. with a mechanical magnification. After that, heat treatment is performed with 8% relaxation to a thickness of 50.
A μm biaxially oriented polypropylene film was molded at a speed of 16 m / min.

The state of the edge roughness of the original sheet at the time of film formation was visually evaluated. As an evaluation standard, ◎ when the edge of the sheet is in close contact with the cooling roll and is linear and very good, ∘ when it is slightly separated from the cooling roll but does not cause a problem in film forming, ○, when it is wavy, Δ, saw When the blade was rough, it was marked with x.

The influence of uneven drawing on the thickness accuracy was evaluated by the thickness pattern of the film measured using an infrared thickness measuring machine WEB GAGE manufactured by Yokogawa Electric Co., Ltd. installed between the tenter and the winder. As an evaluation standard for film thickness accuracy, ◎ is less than ± 1 μm, and ± 1 μm or more is 1.5
Less than μm is ◯, ± 1.5 μm or more and less than 2 μm is △, ± 2
μm or more was defined as x.

Further, continuous operation was carried out for 5 hours, and the number of breaks in the longitudinal stretching of the sheet and the number of breakage of the film in the tenter was evaluated. Further, the obtained film was measured for haze and image value 48 hours after molding. The results are shown in Table 1.

Examples 2-5 Using the same homopolypropylene and talc as in Example 1,
Example 1 was repeated except that the amount of polycyclopentene obtained in Example 1 was changed to that shown in Table 1. The results are shown in Table 1.

Examples 6 to 8 The same procedures as in Example 1 were carried out except that the same homopolypropylene and polycyclopentene as in Example 1 were used and the talc used in Example 1 was changed to the compounding amount shown in Table 1. The results are shown in Table 1.
It was shown to.

Examples 9 and 10 Example 1 except that talc having an average particle size of 1.2 μm was used (Example 9) and talc having an average particle size of 6.1 μm was used (Example 10). The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out without adding polycyclopentene (cyclic olefin polymer) and talc, and the results are shown in Table 1.

Comparative Example 2 The same procedure as in Example 1 was carried out without adding polycyclopentene (cyclic olefin polymer), and the results are shown in Table 1.

Comparative Example 3 The same procedure as in Example 1 was carried out without adding talc, and the results are shown in Table 1.

Comparative Examples 4 and 5 Using homopolypropylene and talc as in Example 1,
Example 1 was repeated except that the amount of polycyclopentene obtained in Example 1 was changed to that shown in Table 1. The results are shown in Table 1.

Comparative Examples 6 and 7 The same homopolypropylene as in Example 1 was used, and Example 1 was used.
Example 1 was repeated except that the polycyclopentene obtained in 1 above and the talc used in Example 1 were mixed in the amounts shown in Table 1.
The results are shown in Table 1.

Example 11 The same procedure as in Example 1 was carried out except that a random copolymer powder having a melt flow rate of 1.8 g / 10 min and an ethylene content of 0.5 mol% was used, and the addition amount of polycyclopentene was 10 ppm. The results are shown in Table 1.

Examples 12 and 13 A powder of a random copolymer having a melt flow rate of 1.2 g / 10 min and an ethylene content of 1.0 mol% was used (Example 12), and a melt flow rate of 2.0 g / 10 min. Example 1 except that a powder of a random copolymer of butene-1 and propylene having a butene-1 component content of 0.5 mol% was used (Example 13).
The same procedure as in Example 1 was performed, and the results are shown in Table 1.

Examples 14 and 15 Using the same crystalline polypropylene as in Example 11, the polycyclopentene content was 100 ppm, the average particle size of talc was 2.0 μm, and the content was 500 ppm (Example 14). Also, the polycyclopentene content should be 1 pp
m, talc average particle size 2.0 μm, content 100 p
The same procedure as in Example 11 was carried out except that pm was used (Example 15), and the results are shown in Table 1.

Comparative Example 8 The crystalline polypropylene of Example 11 was subjected to the same procedure as in Example 1 without adding polycyclopentene (cyclic olefin polymer) and talc, and the results are shown in Table 1.

Comparative Examples 9 and 10 The amount of polycyclopentene added was 0.01 ppm (Comparative Example 9), and the amount of polycyclopentene added was 50.
Example 15 except that it was set to 00 ppm (Example 10).
The results are shown in Table 1.

Comparative Examples 11 and 12 Talc having an average particle size of 13.6 μm was used (Comparative Example 1).
The same procedure as in Example 11 was performed except that 1) and talc having an average particle size of 0.08 μm was used (Comparative Example 12), and the results are shown in Table 1.

Example 16 (Synthesis of catalyst component containing polycyclopentene) 500 ml
100m hexane in a glass reactor equipped with a stirrer
1, 50 mmol of methylaluminoxane and 0.05 mmol of dimethylsilylenebis (methylindenyl) zirconium dichloride were introduced, and the temperature of the system was raised to 60 ° C. Polymerization was started by adding 7.7 g of cyclopentene, and the polymerization was carried out at 60 ° C. for 1 hour. The produced solid part was separated by decantation and 200 ml of hexane
Washed with 5 times with polycyclopentene 1.6
g, aluminum 40 mmol, zirconium 0.04
A solid catalyst component containing 5 mmol was obtained. The crystallinity due to polycyclopentene determined by X-ray diffraction is 64%.
Met.

(Synthesis of Masterbatch) 3000 ml of toluene and 30 mmol of triisobutylaluminum were introduced into a 5000 ml pressure resistant reactor, and the temperature inside the system was raised to 40 ° C. Then, the above polycyclopentene-containing solid catalyst component was introduced into the 0.01 mmol system as zirconium,
Polymerization was started by pressurizing propylene to 3 kgG / cm ² , and the polymerization was carried out at 40 ° C. for 1 hour. The reaction mixture was added to acidic methanol to stop the polymerization, and the obtained solid was filtered and dried under reduced pressure to obtain 330 g of a polymer. The polycyclopentene content in the polymer was 1100 ppm as a result of calculation from the polycyclopentene contained in the solid catalyst component.

The polycyclopentene thus produced was blended with the homopolypropylene shown in Table 1 using a masterbatch containing 1100 ppm to obtain a polypropylene resin composition having a polycyclopentene content of 11 ppm, and shown in Table 1. Talc was added. The results are shown in Table 1.
It was shown to.

[0058]

[Table 1]

Example 17 (Polymerization of cyclobutene) In a glass reactor equipped with a 2000 ml stirrer, under a nitrogen atmosphere, 500 ml of toluene,
Methylaluminoxane 500 mmol and dimethylsilylene bisindenyl zirconium dichloride 0.5 mm
was introduced and the temperature inside the system was raised to 60 ° C. The polymerization was started by adding 200 ml of cyclobutene, and the polymerization was carried out at room temperature for 2 hours. The reaction mixture containing the produced solid was added to a large amount of acidic methanol to terminate the polymerization. The obtained solid was filtered and dried under reduced pressure to obtain 135 g of polycyclobutene. The crystallinity determined by X-ray diffraction was 68%.

The same procedure as in Example 1 was carried out except that the homopolypropylene and talc shown in Table 2 were used and the polycyclobutene obtained above was used in the blending amount shown in Table 2. The results are shown in Table 2.

Examples 18 and 19 The same procedures as in Example 1 were carried out except that the homopolypropylene and talc shown in Table 2 were used and the polycyclobutene obtained in Example 17 was used in the blending amount shown in Table 2. The results are shown in Table 2.

Comparative Examples 13 and 14 The same procedures as in Example 1 were carried out except that the homopolypropylene shown in Table 2 was used and the polycyclobutene obtained in Example 17 was used in the blending amount shown in Table 2. The results are shown in Table 2.

Examples 20 and 21 The same procedures as in Example 19 were carried out except that the same homopolypropylene and polycyclobutene as in Example 19 were used and the talc used in Example 19 was changed to the blending amount shown in Table 2. The results are shown in Table 2.

[0064]

[Table 2]

[Procedure amendment]

[Submission date] December 9, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

The crystalline polypropylene used in the present invention is crystalline and has an isotactic pentad fraction of 0.85 or more. The isotactic pentad fraction as used in the present invention means A. Zambelli et al., Macromolecules, 6 , 925 (19
73) , that is, the fraction in which 5 propylene units are continuously bonded to meso as measured by ¹³ C-NMR.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

The molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the crystalline polypropylene used in the present invention is not particularly limited, Considering the case of film formation, it is preferably 6 to 20 in order to increase melt tension and improve workability. The molecular weight distribution is o- dichlorobenzene was used as a solvent gel permeation chromatography method (hereinafter, also referred to as GPC.) In measured values, calibration curve is used which is calibrated by standard polystyrene.

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Claims (2)

[Claims] 1. A crystalline polypropylene, a cyclic olefin polymer of 0.1 to 1000 ppm, and an average particle size of 0.1.
A polypropylene resin composition comprising 1 to 10 μm of talc of 50 to 4000 ppm. 2. A polypropylene stretched film comprising the polypropylene resin composition according to claim 1 and stretched at least uniaxially.