JPH08208911A - Polypropylene film excellent in transparency - Google Patents

Abstract

PURPOSE: To obtain a polypropylene film excellent in transparency, flexibility and impact resistance. CONSTITUTION: This polypropylene film excellent in transparency comprises 1-99wt.% polypropylene (I) and 1-99wt.% (the total of components I and II being 100wt.%) hydrogenated diene copolymer (II) of a number-average molecular weight of 40000-700000, prepared by hydrogenating an (A)-(B)-(C) block copolymer composed of a polymer block (A) consisting mainly of an aromatic vinyl compound, a polymer block (B) being a polymer based on a conjugated diene and having a content of 1,2-and 3,4-bonds of the conjugated diene of 50% or above and a polymer block (C) of a polybutadiene of a content of 1,2-vinyl bonds of 25% or below so that 70% or above of the double bonds of the conjugated diene part may be saturated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polypropylene film having excellent transparency, impact resistance at low temperature, flexibility and moldability, and more specifically, polypropylene and a specific hydrogenated diene film. The present invention relates to a polypropylene-based film made of a system-based copolymer and having properties suitable for various uses.

[0002]

2. Description of the Related Art Polypropylene films are suitable for various applications because they are inexpensive and have excellent heat resistance and mechanical properties. However, the transparency and impact resistance at low temperature are not sufficient, the flexibility is limited, and the moldability is not sufficient. Therefore, various restrictions are imposed during use. The present invention was developed against the background of such technical problems, and has found a film excellent in transparency, impact resistance, flexibility and molding processability, and completed the present invention.

[0003]

The present invention has been made against the background of the above-mentioned conventional technical problems, and is a novel polypropylene film having excellent transparency, impact resistance, flexibility and molding processability. The purpose is to provide.

[0004]

The present invention relates to a polymer block (A) mainly composed of (a) 1 to 99% by weight of polypropylene and (b) an aromatic vinyl compound, and a polymer mainly composed of a conjugated diene. And a polymer block (B) and 1,2-vinyl bond in which the 1,2- and 3,4-bond content of the conjugated diene portion (hereinafter, referred to as "1,2-bond content etc.") is 50% or more. (A)-(B)-comprising a polybutadiene polymer block (C) having a content of 25% or less
(C) A block copolymer, or a block copolymer in which the block copolymer unit is extended or branched via a coupling agent residue, is hydrogenated, and a double bond of a conjugated diene portion is 70%. The number average molecular weight saturated above is 4 to
A polypropylene film having excellent transparency, which is characterized by comprising 1 to 99% by weight of a hydrogenated diene copolymer of 700,000 (hereinafter sometimes referred to as film (I)).
Is provided. Further, the present invention comprises 1 to 98% by weight of the component (A), 1 to 98% by weight of the component (B), and 1 to 98% by weight of an olefin polymer mainly containing ethylene as the component (C). And a polypropylene film having excellent transparency (hereinafter sometimes referred to as film (II)).

First, the polypropylene (a) used in the present invention is a crystalline polypropylene, and a homopolymer of propylene or an α-olefin such as ethylene, 1-butene or 1-hexene is preferably 15 mol% or less, preferably. Is a polymer containing 0.5 to 10 mol%. The copolymer may be a random copolymer, a blended product with a homopolymer obtained by multistage polymerization, or an ordinary blended product. The density of polypropylene is 0.885.
˜0.915 g / cm ³ , and the melt flow rate (MFR) is 0.1 to 50 g / 10 minutes, preferably 0.1.
It is 2 to 40 g / 10 minutes. As a method for obtaining these polypropylenes, there are a method using a Ziegler-Natta type catalyst, a method using a Kaminsky type catalyst, and the like. As the component (a) of the present invention, polypropylene by any polymerization catalyst is also suitable. Used for. However, the stereoregularity of the propylene unit is preferably isotactic or syndiotactic as the component (a) of the present invention.

The (b) hydrogenated diene copolymer used in the present invention is composed of an aromatic vinyl compound and a conjugated diene. As the aromatic vinyl compound used here, styrene, α-methylstyrene, p-methylstyrene, t-butylstyrene, divinylbenzene, N, N
-Dimethyl-p-aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene, vinyl pyridine and the like can be mentioned, and among these, styrene and α-methylstyrene are preferable, and styrene is particularly preferable. Further, as the conjugated diene, 1,3-butadiene, isoprene,
2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3
-Hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene and the like, but hydrogenated diene-based copolymers that are industrially applicable and have excellent physical properties 1,3-Butadiene, isoprene and 1,3-pentadiene are preferred, and 1,3-butadiene and isoprene are particularly preferred.

The (b) hydrogenated diene-based copolymer of the present invention is
A polymer block (A) mainly composed of an aromatic vinyl compound, a polymer block (B) mainly composed of a conjugated diene and having a 1,2-bond content of the conjugated diene portion of 50% or more; 1,2-vinyl bond content is 25
% Of polybutadiene polymer block (C) or less (A)-(B)-(C) block copolymer.

The block (A) in the component (B) of the present invention
Is a polymer block mainly composed of an aromatic vinyl compound, specifically, a homopolymer block of an aromatic vinyl compound, or a copolymer of an aromatic vinyl compound and a conjugated diene, wherein the aromatic vinyl compound is A polymer block in which 70% or more of the conjugated diene portion of the polymer block having 90% by weight or more is hydrogenated is preferable.

The block (B) in the component (B) is preferably a conjugated diene homopolymer or an aromatic vinyl compound-conjugated diene copolymer. That is, as the structure after hydrogenation, for example, when the conjugated diene is butadiene, a structure similar to a rubber-like ethylene-1-butene copolymer block or an aromatic vinyl compound-ethylene-1-butene copolymer is shown. Polymer blocks are preferred as block (B). The preferred amount of the aromatic vinyl compound used in the block (B) is 35% by weight of the monomer constituting the block (B).
The content is more preferably 30% by weight or less, further preferably 25% by weight or less, and if it exceeds 35% by weight, the glass transition temperature of the block (B) increases, resulting in poor impact resistance and flexibility. The preferred 1,2-bond content of the conjugated diene moiety before hydrogenation of the block (B) is 50 to 95%,
It is more preferably 60 to 95%, and if less than 50% or more than 95%, by hydrogenation, for example, in the case where the conjugated diene is butadiene, a crystal structure derived from a polyethylene chain or a polybutene-1 chain is exhibited, and resinous As a result, the flexibility is poor and the impact resistance is also low.

The block (C) in the component (B) of the present invention
Becomes a crystalline polymer block having a structure similar to that of ordinary low density polyethylene by hydrogenation. Preferred polybutadiene before hydrogenation in block (C) 1,
The 2-vinyl bond content is usually 25% or less, more preferably 20% or less, most preferably 15% or less. When the 1,2-vinyl bond content of the polybutadiene before hydrogenation in the block (C) exceeds 25%, the crystal melting point after hydrogenation is remarkably lowered, the heat sealing property is deteriorated, and the impact resistance is lowered. Is also inferior. In the component (b) of the present invention, the content of the block (A) is preferably 1 to 70.
% By weight, more preferably 2 to 60% by weight, further preferably 3 to 55% by weight, the content of the block (B) is preferably 10 to 95% by weight, more preferably 20 to 90% by weight, further preferably 30 to 80% by weight, the content of block (C) is preferably 5 to 90% by weight, more preferably 5 to 70% by weight, further preferably 5 to 50% by weight.
Is. When the content of block (A) is less than 1% by weight,
The transparency of the obtained film is lowered due to the deterioration of the surface appearance, and when it exceeds 60% by weight, moldability and flexibility are insufficient. Further, when the content of the block (B) is less than 10% by weight, the transparency is lowered, and when it exceeds 95% by weight, the moldability is lowered. Further, when the content of the block (C) is less than 5% by weight, impact resistance is lowered, while when it exceeds 90% by weight, flexibility is deteriorated.

In the hydrogenated diene-based copolymer used as the component (b) in the present invention, the polymer molecular chain represented by the following general formula is extended or branched by adding a coupling agent. The block copolymer may be a prepared block copolymer. [(C)-(B)-(A)] n-Z or [(C)-
(B)-(A)] Z [(A)-(B)] [(wherein (A), (B), and (C) are the same as above. N is an integer of 2 to 4, Z is a cup) A ring agent residue is shown.] Examples of the coupling agent at this time include diethyl adipate, divinylbenzene, methyldichlorosilane, tetrachlorosilane, butyltrichlorosilane, tetrachlorotin, butyltrichlorotin, dimethylchlorosilane, and tetrachlorogermanium. 1,2-dibromoethane, 1,4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidized linseed oil, tolylene diisocyanate, 1,2,4-benzenetriisocyanate, and the like.

The hydrogenated diene polymer used as the component (b) in the present invention may be modified with a functional group, such as an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group and an epoxy group. The unsaturated compound having at least one functional group selected from the above can be used for modification with a kneader, a mixer, an extruder or the like. The (b) hydrogenated diene-based copolymer used in the present invention has at least 70%, preferably 80% of the double bonds of the conjugated diene moieties in the block (A), the block (B) and the block (C). As described above, more preferably 90% or more is required to be hydrogenated and saturated, and if less than 70%, the transparency, heat sealability, and moldability of the obtained film are insufficient, which is not preferable.

The number average molecular weight of the hydrogenated diene-based copolymer (b) of the present invention is preferably 4 to 700,000, more preferably 1
If it is from 0 to 600,000 and below 40,000, the impact resistance of the resulting film will be poor, and if it exceeds 700,000, the moldability will be poor. A blend of two or more hydrogenated diene-based polymers is also suitably used as the component (b) of the present invention. The (b) hydrogenated diene-based copolymer used in the present invention is, for example, JP-A-2-133406.
It can be obtained by the method disclosed in JP-A-5-170844 and the like.

In the film (I) of the present invention, (a)
1 to 99% by weight, preferably 10 to 99% by weight,
More preferably 30 to 99% by weight, the component (B) is 1 to 9
It is 9% by weight, preferably 1 to 90% by weight, and more preferably 1 to 70% by weight [(A) + (B) = 100% by weight]. If the amount of the component (a) is less than 1% by weight and / or the amount of the component (b) exceeds 99% by weight, moldability is deteriorated. When the amount of the component (b) is less than 1% by weight and / or the amount of the component (a) exceeds 99% by weight, the transparency, impact resistance and flexibility are poor. The film of the present invention (I
(I) is a film (I) further added with an olefin polymer mainly containing ethylene as the component (C). With the addition of this component (c), transparency, flexibility,
In addition to impact resistance, it is possible to obtain a film having excellent heat sealability.

The (c) ethylene-based olefin polymer used in the film (II) is a polymer having ethylene in excess of 15 mol%, and is a linear or branched olefin polymer. is there. As a typical example of this linear or branched olefin polymer,
Examples thereof include ethylene-α-olefin-based copolymers and high-pressure low-density polyethylene. Here, as the α-olefin in the ethylene-α-olefin-based copolymer,
Those having 3 to 12 carbon atoms are general, and specifically, propylene, 1-butene, 2-butene, 2-methyl-1-propene, 1-pentene, 2-methyl-1-butene, 1-
Hexene, 4-methyl-1-pentene, 2-methyl-1
-Pentene, 3-methyl-1-pentene, 1-heptene, 5-methyl-1-hexene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 1-octene, 1-decene, and These mixtures are mentioned.
Among these α-olefins, propylene, 1-butene, 1-hexene and 1-octene are preferred, of which 1-butene is most preferred, propylene and 1-octene are preferred, and 1-hexene is then preferred. That is, as the component (c), an ethylene-1-butene copolymer is most preferable, then an ethylene-propylene copolymer and an ethylene-1-octene copolymer are preferable, and then an ethylene-1-hexene copolymer is preferable. preferable.

If desired, the component (c) may be copolymerized with a non-conjugated diene. Examples of the non-conjugated diene that may be used as the component (c) include dicyclopentadiene, tricyclopentadiene, 5-methyl-2,5-
Norbonadiene, 5-methylene-2-norbornene, 5
-Ethylidene-2-norbornene, 5-isopropenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5- (1-butenyl) -2-norbornene,
Cyclooctadiene, vinylcyclohexene, 1,5
9-cyclododecatriene, 1,4-hexadiene,
1,6-octadiene, 1,7-octadiene, 1,8
-Nonadiene, 1,9-decadiene, 3,6-dimethyl-1,7-octadiene and the like, and preferably 5
-Ethylidene-2-norbornene, dicyclopentadiene. These may be used alone or in combination of two or more.

The above-mentioned various olefin polymers mainly composed of ethylene are preferably used alone or as the component (c), but may be a blend of two or more polymers. Examples of the blend include a blend of two polymers, a blend of linear polymers, a blend of branched polymers, and a blend of linear polymers and branched polymers. Any combination of blends is suitable as component (C).

In the film (II) of the present invention,
The component (a) is 1 to 98% by weight, preferably 10 to 98% by weight, more preferably 30 to 98% by weight, further preferably 40 to 98% by weight, particularly preferably 50 to 98% by weight, and the component (B). Is 1 to 98% by weight, preferably 1 to 90
% By weight, more preferably 1 to 70% by weight, further preferably 1 to 60% by weight, particularly preferably 1 to 50% by weight,
The component (c) is 1 to 98% by weight, preferably 1 to 90% by weight, more preferably 1 to 70% by weight, further preferably 1 to 60% by weight, particularly preferably 1 to 50% by weight [however, ) + (B) + (c) = 100% by weight].
When the content of the component (a) is less than 1% by weight, the molding processability is deteriorated, and when it exceeds 98% by weight, the transparency and impact resistance of the obtained film are deteriorated. Further, if the content of the component (b) is less than 1% by weight, the transparency and impact resistance of the obtained film will be poor, and if it exceeds 98% by weight, the moldability will be insufficient. Further, when the content of the component (c) is less than 1% by weight, the heat sealability is not sufficiently improved, and when it exceeds 98% by weight, moldability, transparency, impact resistance and flexibility are deteriorated. .

The polypropylene film of the present invention comprises
Additives used for ordinary thermoplastic materials can be added as required. For example, plasticizers or reinforcing agents such as phthalates, fillers for rubber such as paraffin oil, fillers such as silica, talc and calcium carbonate, antioxidants, ultraviolet absorbers, antistatic agents, lubricants,
Antibacterial agents, flame retardants, foaming agents, colorants, pigments, carbon fibers, metal fibers, glass beads, crosslinking agents, crosslinking aids, etc., or mixtures thereof can be added. Further, as the components constituting the film of the present invention, the above (a) to (c)
Thermoplastic materials other than components and rubbery polymers, such as polybutene, propylene-1-butene copolymer, poly-4
Polymethylpentenes such as -methyl-1-pentene,
Ethylene-ethylene olefin copolymers such as norbornene copolymers, hydrogenated terpene resins, petroleum resins,
Polyisobutylene, polystyrene, polymethyl acrylate, polyacrylic acid alkyl ester such as polyethyl acrylate, polymethyl methacrylate, polymethacrylic acid alkyl ester such as polyethyl methacrylate, polybutadiene polymer and / or hydrogenated product thereof, Styrene-butadiene copolymer, styrene-isoprene copolymer, butadiene-isoprene copolymer and / or hydrogenated product thereof, ethylene-vinyl acetate copolymer, ethylene-
Vinyl alcohol copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, acrylic Rubber, ethylene ionomer, etc. may be blended, and a thermosetting polymer such as epoxy resin, phenol resin, silicone resin, etc. may be blended within a range not impairing the properties of the film of the present invention. Is.

The film of the present invention can be easily molded by a conventionally known method such as T-die molding, inflation molding and calender molding. Further, the film of the present invention,
It is also possible to perform a stretching process. As a method for performing the stretching treatment, known uniaxial stretching methods such as roll stretching, roll rolling, and tenter transverse uniaxial stretching, and known biaxial stretching methods such as tenter biaxial stretching and tubular biaxial stretching can be adopted. . When performing the stretching treatment, the stretching temperature is preferably room temperature to the melting point of polypropylene or less, and the stretching ratio is preferably 2 to 10 times. However, the MD and TD stretch ratios do not necessarily have to be balanced, and can be arbitrarily selected according to the respective applications. In addition, depending on the purpose, the films of the present invention, or by laminating the film of the present invention and a film of a polyolefin resin or an ethylene-α-olefin resin or a mixture thereof, a film having further excellent properties. It is possible to obtain. It is also possible to laminate with a material such as ethylene-vinyl acetate copolymer, ethylene-unsaturated carboxylic acid copolymer or its derivative copolymer, ethylene-vinyl alcohol copolymer, and these films and By laminating with the film of the invention, it is possible to obtain a film for various purposes. As a method for obtaining these laminates, a coextrusion T-die molding method, a coextrusion inflation molding method and the like are exemplified, but the method is not particularly limited.

Since the film of the present invention is excellent in transparency, flexibility and impact resistance, for example, various clothing such as shirts and stockings, bedding such as futons and pillows, and the like,
Used for various food packaging, daily sundries packaging, industrial material packaging, laminating various rubber products / resin products / leather products, elastic tapes used for paper diapers, industrial products such as dicing films, building materials and steel plate protection. Sheets such as protect film, meat and fish trays, fruit and vegetable packs, frozen dessert food containers, home electric appliances such as TVs, stereos, vacuum cleaners, bumper parts, body panels, automotive interior and exterior parts such as side seals, road paving materials ,
It can be used for a wide range of applications such as waterproof / water-proof sheets, civil engineering packing, and other daily necessities, leisure items, toys, industrial items, furniture items, writing instruments, medical instruments, and the like.

[0021]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples as long as the gist of the present invention is not exceeded. In the examples, parts and% are by weight unless otherwise specified. In addition, evaluation of various physical properties in the examples was performed by the following methods. Vinyl bond content of conjugated diene Calculated by Hampton method using infrared analysis. Hydrogenation rate Using tetrachloroethylene as a solvent, 100 MHz, ¹ H-N
It was calculated from the MR spectrum. The number average molecular weight of hydrogenated diene copolymer trichlorobenzene was used as a solvent, and it was determined in terms of polystyrene using gel permeation chromatography (GPC) at 135 ° C. Molding workability The workability during film molding was evaluated as follows. ◯: Workability during molding is good and film can be formed under a wide range of extrusion conditions and take-off conditions. △: Film can be formed, but extrusion conditions and take-off conditions are narrow. For example, transparency is inferior in workability during molding. The total haze was measured in accordance with JIS K6782 and used as an index of transparency. Impact resistance The film punching strength was measured according to JIS Z1707 and used as an index of impact resistance. Flexibility Young's modulus was measured according to JIS K7127 and used as an index of flexibility. Heat-sealability The peel strength of the heat-sealed portion was measured according to JIS Z1707 and used as an index of heat-sealability.

Reference Example Various components used in the formulations shown in Examples and Comparative Examples are as follows. Polypropylene PP-1 [Chisso Petrochemical Co. FM821] density ^{0.9g / cm 3, MFR 7g /} 10 min PP-2 [manufactured by Mitsui Toatsu Chemicals Inc. EFL-200] Density 0.9 g / cm ³ , MFR 6 g / 10 min PP-3 [Mitsubishi Chemical Corp. FX-4] density ^{0.9g / cm 3, MFR 7g /} 10 min PP-4 [manufactured by Sumitomo Chemical Co., Ltd. FL6315G] density 0.9g / cm ^3, MFR 6g / 10 min PP-5 [Chisso Petrochemical Co. FM831-B] density ^{0.9g / cm 3, MFR 6.5g /} 10 minutes PP-6 [manufactured by Mitsubishi Chemical Corporation 3501F ] density 0.9 g / cm ^3, the microstructure shown in MFR 7 g / 10 min hydrogenated diene copolymer table 1, the number-average molecular weight, hydrogenated diene copolymer hydrogenation ratio (Q-1~Q- 9).

[Table 1] Olefin-based polymer R-1 [ethylene-1-butene copolymer: 1-butene content 20%, MFR 6.6 g / 10 min] R-2 [ethylene-1-butene copolymer: 1 -Butene content 20%, MFR 0.9 g / 10 min] R-3 [ethylene-1-butene copolymer: 1-butene content 21%, MFR 6.5 g / 10 min] R-4 [ethylene-propylene copolymer : Propylene content 22%, MFR 3.5 g / 10 min] R-5 [ethylene-propylene copolymer: propylene content 23%, MFR 0.8 g / 10 min] R-6 [ethylene-1-octene copolymer: 1 -Octene content 24%, MFR 9.5 g / 10 min]

Examples 1 to 13 and Comparative Examples 1 to 7 Compositions having the formulations shown in Tables 2 and 3 were used, and the caliber was 50 mm and L / D3.
The mixture was kneaded at 180 to 240 ° C. using the extruder of No. 6 and supplied to the T die, and the die temperature was 210 to 230 ° C. and the thickness was 50 μm
Of polypropylene film was produced. Tables 2 and 3 show the results of evaluation of the molding processability during film production and the physical properties of the obtained film.

[Table 2]

[Table 3] As is clear from the results of Examples 1 to 6, the film (I) of the present invention is excellent in transparency and impact resistance, has good flexibility, and is also excellent in moldability. I understand. Further, as is clear from the results of Examples 7 to 13, the film (II) of the present invention has extremely good heat sealability in addition to transparency, impact resistance, flexibility and moldability. I understand. On the other hand, Comparative Example 1 is an example using only the component (a), but is inferior in transparency and impact resistance as compared with the film of the present invention, and is insufficient in flexibility and heat sealability. I know there is. Comparative Examples 2 to 4 are examples in which the structure of the hydrogenated diene-based copolymer is out of the scope of the present invention. Among these, Comparative Example 2 and Comparative Example 4 are inferior in both transparency and heat sealability, and in particular Comparative Example 2 is inferior in flexibility. In Comparative Example 3, the transparency and flexibility are good, but the heat sealability is insufficient and the impact resistance is poor. Comparative Examples 5 to 7 do not use the component (b) but only the components (a) and (c). Both of them have insufficient transparency and flexibility, and further, Comparative Example 5 does not have sufficient impact resistance at low temperature, and Comparative Example 6 and Comparative Example 7
Then, it is understood that not only the low temperature impact resistance is not sufficient but also the heat sealability is inferior.

[0024]

INDUSTRIAL APPLICABILITY The present invention provides a film made of polypropylene and a specific hydrogenated diene-based copolymer, and is superior in impact resistance, flexibility, heat sealability, etc. to conventional films. It is possible to provide a film having excellent properties. The film of the present invention can widely meet various demands from the industrial world due to the above excellent properties. Specifically, it is used for packaging various clothing such as shirts and stockings, bedding such as bedding and pillows, various food packaging, daily sundries packaging, industrial material packaging, various rubber products, resin products, leather products, etc. Elastic tape used for laminates, paper diapers, etc., film applications such as dicing film, meat and fish trays,
It can be used in a wide range of applications such as fruit and vegetable packs, sheets for frozen dessert food containers, home appliances, automotive interior and exterior parts, waterproof sheets, leisure products, toys, industrial products, furniture products, writing instruments, medical instruments, etc. it can.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kaname Fujimaki, 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd. (72) Kazumi Ogaki, 2-1-211 Tsukiji, Chuo-ku, Tokyo No. Japan Synthetic Rubber Co., Ltd. (72) Inventor Toru Shibata 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (2)

[Claims] 1. A polymer block (A) mainly comprising (a) 1 to 99% by weight of polypropylene and (b) an aromatic vinyl compound, a polymer mainly comprising a conjugated diene, wherein 50% of 2- and 3,4-bond content
(A)-(B)-(C) block copolymer comprising the above polymer block (B) and the polybutadiene polymer block (C) having a 1,2-vinyl bond content of 25% or less, or The block copolymer unit is hydrogenated with a block copolymer extended or branched via a coupling agent residue, and the double bond of the conjugated diene moiety is 70
% Of the hydrogenated diene-based copolymer having a number average molecular weight of 40,000 to 700,000 and having a saturation ratio of 1 to 99% by weight, and having excellent transparency. 2. An olefin-based polymer 1-9 containing (a) component 1 to 98% by weight, (b) component 1 to 98% by weight and ethylene as a main component (c) as claimed in claim 1.
A polypropylene film having excellent transparency, which is characterized by comprising 8% by weight [(a) + (b) + (c) = 100% by weight].