JPH08120130A - Polypropylene resin composition for extruded film and extruded film produced thereof - Google Patents

Abstract

PURPOSE: To provide a polypropylene resin composition giving a film having excellent transparency, anti-blocking property and scratch resistance and exhibiting high antistaticity at the initial stage after the film-forming process. CONSTITUTION: This polypropylene resin composition for extruded film is composed of a crystalline polypropylene, an antistatic agent and an anti-blocking agent. It can be produced by compounding 100 pts.wt. of a crystalline polypropylene with 0.10-1.0 pts.wt. of an antistatic agent and 0.01-0.5 pts.wt. of an anti-blocking agent consisting of particles of a crosslinked organic polymer compound having an average particle diameter of 1-10μm. A film having an initial intrinsic surface resistivity of <=1×10<13> Ω is produced by the extrusion molding of the polypropylene resin composition for extruded film.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polypropylene resin composition for extruded films. More specifically, the present invention relates to a polypropylene resin composition which is excellent in transparency, antiblocking property and scratch resistance when extruded, and which can give a film having good antistatic property in the early stage after film formation.

[0002]

2. Description of the Related Art Extruded polypropylene films are widely used because they have good physical properties, are inexpensive, and have relatively good heat resistance. However, in general, an extruded film of a polypropylene resin composition is apt to cause so-called blocking between the films. Also, the electrical insulation resistance is large,
As a result, static electricity is easily generated due to friction and accumulates, and the adhesion of dust and the like becomes a problem. As an improvement method, an anti-blocking agent having a BET specific surface area of 200 m ² / g
Hereinafter, inorganic particles such as zeolite and silica having a bulk specific gravity of 0.2 or more (JP-A-56-4642) and O on the particle surface.
It has been proposed to use inorganic particles such as zeolite and silica having an H group content of 200 μmol / g or less (JP-A-4-22044). Further, it is known to add a fatty acid ester of glycerin or the like as an antistatic agent during molding.

[0003]

However, in the above method, when the inorganic particles are added in an amount necessary to obtain a sufficient antiblocking property, the transparency and gloss of the film are deteriorated. Further, there is a problem in that the scratches on the surface due to the rubbing of the films due to the shape and hardness of the surface protrusions of the film, that is, the scratch resistance becomes poor.

If the above-mentioned antistatic agent is added in an amount necessary for obtaining sufficient antistatic property, problems such as deterioration of transparency of the film and embossing occur. The composition in which fine particles such as silica and an antistatic agent are combined has poor antistatic properties in the initial stage after film formation, and further has antiblocking properties, transparency, antistatic properties, slip properties, and scratch resistance. There was a problem that the balance of sex was poor.

An object of the present invention is to provide a resin composition for an extruded film which solves the above-mentioned drawbacks and has a good balance of antiblocking property, transparency, antistatic property, slip property and scratch resistance. To do.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have solved the above problems and have excellent transparency, antiblocking property and scratch resistance, and an extruded film having good antistatic properties in the initial stage after film formation. The present invention has been completed after intensive studies to develop a polypropylene resin composition for use in a car.

That is, the present invention is a polypropylene resin composition for an extruded film comprising crystalline polypropylene, an antistatic agent and an antiblocking agent, wherein the antistatic agent is added in an amount of 0.10 to 100 parts by weight of the crystalline polypropylene.
A polypropylene resin for an extruded film, which is blended with 0.01 to 0.5 part by weight of an anti-blocking agent which is an organic polymer compound particle having 1.0 part by weight and an average particle size of 1 to 10 μm and having a crosslinked structure. It is a composition. In addition, the present invention has an initial surface resistivity of 1 × obtained by extrusion-molding the polypropylene resin composition for an extruded film.
It is a film of 10 ¹³ Ω or less.

In the present invention, the crystalline polypropylene is not particularly limited as long as it is a crystalline polypropylene, but in the case of isotactic polypropylene, ¹³ C-
It is preferable that the isotactic pentad fraction measured by NMR is high stereoregularity of 0.90 or more, and in the case of syndiotactic polypropylene, the syndiotactic pentad fraction measured by ¹³ C-NMR is 0.7.
Those having high stereoregularity of 0 or more can be preferably used.

Further, ethylene or α- having 4 or more carbon atoms
Copolymers with olefins can also be used, and both isotactic polypropylene and syndiotactic polypropylene have a content of 6 parts by weight or less as ethylene or other α-olefin having 4 or more carbon atoms in the copolymer. Is preferably used.

As the molecular weight of these crystalline polypropylenes, the melt flow index measured at 230 ° C. is 3.
It is preferable from the viewpoint of the physical properties of the extruded film to use one having a relatively high molecular weight of 0 or less, preferably 20 or less.

As the antistatic agent in the present invention, those generally used for polyolefin films can be used. For example, (1) cationic amines such as primary amine salts, tertiary amines, quaternary ammonium compounds, and pyridine derivatives; (2) sulfated oils, soaps, sulfated ester oils, sulfated amide oils , Sulfates of olefins,
Anionic salts such as fatty alcohol sulfate ester salts, alkyl sulfate ester salts, fatty acid ethyl sulfonate salts, alkylnaphthalene sulfonate salts, alkylbenzene sulfonate salts, succinic acid ester sulfonate salts, and phosphoric acid ester salts, (3) Many Partial fatty acid ester of polyhydric alcohol, ethylene oxide adduct of fatty alcohol, ethylene oxide adduct of fatty acid, ethylene oxide adduct of alkylphenol, ethylene oxide adduct of alkylphenol, ethylene oxide adduct of partial fatty acid ester of polyhydric alcohol In general, nonionic compounds such as polyethylene glycol and amphoteric compounds such as (4) carboxylic acid derivatives and imidazoline derivatives can be used, but particularly nonionic compounds, especially polyoxyethylene alkylamido. Or polyoxyethylene alkyl amides or their fatty acid esters, fatty acid esters of glycerol are preferred. Further, it is more preferable to use an amine antistatic agent or an amide antistatic agent in combination with glycerin fatty acid ester.

Crystalline polypropylene 1 of the above antistatic agent
As an addition ratio with respect to 00 parts by weight, 0.10 to 1.0
Parts by weight. If the amount is less than this, the effect of improving the antistatic property is not obtained, and if the amount is more than that, the effect is not particularly improved, and rather the antiblocking property, the adhesion to the cooling roll, the transparency after aging and the like are lost, which is not preferable. Particularly preferred is 0.20 to 0.8 parts by weight.

In the present invention, the antiblocking agent is an organic polymer compound particle having an average particle diameter of 1 to 10 μm and a crosslinked structure. As such, for example, a radical polymerizable double bond is used as a molecule. Emulsion so that a compound having two or more of them and an acrylic ester and / or a methacrylic ester having one radical-polymerizable double bond can be adjusted to an appropriate particle size by controlling the type and concentration of the dispersant. It is possible to polymerize and produce. A preferable composition is polymer particles in which the content of acrylic acid ester and / or methacrylic acid ester in the polymer of the polymer compound particles is 50 to 95 parts by weight.

The compound having two or more radical-polymerizable double bonds in the molecule has, for example, 1 to 1 carbon atoms.
Acrylic acid ester or methacrylic acid ester, which is a dihydric or trihydric alcohol at 12, specifically,
Examples thereof include divinylbenzene or a nucleus-substituted derivative thereof, ethylene glycol di (meth) acrylate, and trimethylolpropane tri (meth) acrylate. Further, in the production of organic polymer compound particles, it is possible to use in combination with other compounds having a radical-polymerizable double bond in addition to the above compounds, such as styrene or a derivative thereof, α -Methylstyrene or a derivative thereof, acrylonitrile, methacrylonitrile and the like are exemplified.

The proportion of acrylic acid ester and / or methacrylic acid ester in the polymer is preferably 50 to 95 parts by weight, and 50 parts by weight of acrylic acid ester and / or methacrylic acid ester in the polymer. If it is smaller, the transparency and scratch resistance will be poor. The amount of the compound having two or more radically polymerizable double bonds in the molecule is preferably 5 to 50 parts by weight in the polymer, and if less than 5 parts by weight, the heat resistance is insufficient.
If the amount is more than the amount by weight, the particle hardness increases and the scratch resistance becomes poor, which is not preferable.

The proportion of the anti-blocking agent, which is the above-mentioned polymer compound particles, used is 0.01 to 0.5 part by weight per 100 parts by weight of crystalline polypropylene. If it is less than this range, there is no blocking preventing effect, and if it is more than that, it is not particularly improved, and transparency is lost, which is not preferable. Especially preferred is 0.05 to 0.3
Parts by weight.

What is important in the present invention is that the main effect can be obtained by using an antiblocking agent which is a polymer compound particle and an antistatic agent in combination.

In the present invention, the above-mentioned composition can be obtained by uniformly dispersing it by any known method. For example, an extrusion melt blending method, a Banbury blending method, and the like. Also, it may be added as a masterbatch.

Further, generally used additives such as slip agents, stabilizers and nucleating agents can be appropriately added to the composition of the present invention as needed.

The extruded film of the present invention is an unstretched film formed by a known method such as the T-die method or the inflation method. The thickness of the film is not particularly limited, but it is preferably 5 to 150 μm, more preferably Is 15 to 60 μm.

The extruded film of the present invention is dry laminated or extruded with other films such as biaxially oriented polypropylene film, unstretched nylon film, stretched nylon film, stretched polyethylterephthalate film, aluminum foil, papers and the like. It can be used as a composite film formed by a known method such as laminating or a coextruded composite film by a T-die method or an inflation method, and the thickness of the unstretched film layer is not particularly limited, but is 5 to 150 μm. Preferably, more preferably 1
It is 5-60 micrometers.

The film obtained by extrusion molding using the composition of the present invention has a good antistatic property in the initial stage after film formation, and has transparency, slipperiness, scratch resistance between films, and so-called resistance. The film has an antistatic property such that the scratch resistance is good and the initial surface specific resistance represented by the index of the antistatic property is 1 × 10 ¹³ Ω or less.

Since the extruded film of the present invention exhibits extremely stable antistatic property in the initial stage after film formation, it is economically extremely stable without causing troubles due to static electricity in the secondary processing step and the packaging step. It is a film.

The extruded film of the present invention can be subjected to surface treatment such as corona discharge treatment or flame treatment by a method usually adopted in industry.

[0025]

EXAMPLES In order to explain the present invention in more detail, the following examples are shown, but the present invention is not limited to these. In the examples, each measurement item was measured according to the following method. (1) Melt flow index: ASTM D-12
38. (2) Haze: According to ASTM D-1003. (3) Anti-blocking property: Two films cut into a predetermined size are stacked, weighted to 20 g / cm ² , left in a constant temperature chamber at 50 ° C., then taken out from the constant temperature chamber, and the adhesion area ratio of the film is adjusted. It was visually determined. (4) Antistatic property: After film formation, after conditioning for 72 hours at 23 ° C. and 60% relative humidity, a SM-10E type ultra-ultra-insulator manufactured by Toa Denpa Kogyo Co., Ltd. was used and JIS −
The surface resistivity was measured according to K6911. (5) Embossing: After film formation, the haze was measured after 20 days of treatment in a circulation type constant temperature bath heated to 50 ° C. (6) Coefficient of friction (tan θ): ASTM D-1894
Compliant with. After film formation, heat treatment was carried out for 24 hours in a circulation type constant temperature bath heated to 35 ° C., taken out to room temperature, and 1 hour later, the slip property was measured. (7) Scratch resistance: Two rolls of polypropylene film were superposed on each other, rubbed 3 times with a 2 kg iron block as a load, and the haze of two samples was measured by the method (2) and rubbed. The difference from the haze of two samples before being combined (Δ haze) was obtained and judged.

[Reference Example] [Preparation of catalyst] A vibration mill equipped with four grinding pots having an inner volume of 4 liters and containing 9 kg of steel balls having a diameter of 12 mm is prepared. 300 g of magnesium chloride, 115 ml of diisobutyl phthalate, and 60 ml of titanium tetrachloride were added to each pot in a nitrogen atmosphere and pulverized for 40 hours.

A 200 ml flask was charged with 5 g of the co-ground product, 100 ml of toluene was added, the mixture was stirred at 114 ° C. for 30 minutes, and then allowed to stand to remove the supernatant. Then n
-The solid content was washed with 100 ml of heptane three times at 20 ° C, and then dispersed in 100 ml of n-heptane to obtain a transition metal catalyst slurry. The resulting transition metal catalyst contained 1.8 wt% titanium and 18 w diisobutyl phthalate.
It contained t%.

[Production of Propylene-Ethylene Copolymer]
Preparation of polymerization was carried out by charging 25 kg of propylene into a jacketed autoclave having an internal volume of 100 liters, which was sufficiently dried and purged with nitrogen, and further purged with propylene.
On the other hand, n-heptane 500m in a 1 liter flask
1, triethylaluminum 1.5 ml, cyclohexylmethyldimethoxysilane 2.2 ml and 0.30 g of the transition metal catalyst obtained by the above catalyst preparation as a solid content were mixed, and the mixture was pressed into the prepared autoclave having the internal volume of 100 liters. . Then, after charging a predetermined amount of hydrogen and ethylene, warm water was passed through the jacket so that the internal temperature was 70 ° C. and the gas phase concentrations of hydrogen and ethylene were 3.0 mol% and 3.0 mol%, respectively. While charging, propylene was continuously charged at 5 kg / h for polymerization, and after 3 hours, diethylene glycol monoisopropyl ether 6.0
ml was press-fitted, and the mixture was further stirred at 60 ° C. for 30 minutes to complete the polymerization.

[Post-treatment] The obtained copolymer slurry is
The inner diameter of the slender part is 15 cm, the inner diameter of the thick part of the upper part is 30 cm, the length of the slender part is 5 m, and the length of the thick part of the upper part is 1 m. Is a propylene washing liquid introduced at a rate of 100 kg / h, a counter washing tower is 110 kg / h of washing liquid, and a copolymer slurry washed from below is 40 kg / h.
Take out with h. The taken out copolymer slurry was discharged into a cyclone kept at atmospheric pressure through a double tube which can be heated through an outer tube having an inner diameter of 20 cm and a length of 60 m through a steam of 1 kg / cm ² gauge, and the obtained powder was Further, it was dried at 50 ° C. and 60 mmHg for 10 hours to give 13.3.
kg of propylene / ethylene copolymer was obtained. The melt flow index (hereinafter referred to as MFI) of the copolymer thus obtained was 8.3 g / 10 min.

Example 1 100 parts by weight of the propylene / ethylene copolymer obtained in Reference Example was added with 0.11 part by weight of a phosphorus antioxidant, 0.08 part by weight of a phenolic antioxidant, and an amide-based antioxidant as an antistatic agent. Armostat TM310 (manufactured by Lion Akzo Co., Ltd.)
Is 0.1 part by weight, glycerin fatty acid ester-based liquemal 100A (manufactured by Riken Vitamin Co., Ltd.) is 0.25 part by weight, and an anti-blocking agent (hereinafter referred to as AB agent) is methylmethacrylate / divinylbenzene / hydroxypropyl. 0.3 parts by weight of cross-linked polymer particles having an average particle diameter of 2.2 μm at a weight ratio of methacrylate = 90/5/5 were mixed with a 20 liter Henschel for 2 minutes and granulated with a 65 mmφ extruder. The pellets are melt extruded with a 40 mmφT die at a resin temperature of 240 ° C. to a thickness of 30 μm.
An unstretched film of was obtained. Table 1 shows the evaluation results.

Example 2 AB agent was methyl methacrylate / divinylbenzene / styrene / hydroxypropyl methacrylate = 70/5
Example 1 was repeated except that 0.3 parts by weight of crosslinked polymer particles having an average particle size of 2.2 μm were used at a weight ratio of / 20/5. Table 1 shows the evaluation results.

Example 3 AB agent was methyl methacrylate / divinylbenzene / styrene / hydroxypropyl methacrylate = 55/5
Example 1 was repeated except that 0.3 part by weight of crosslinked polymer particles having an average particle diameter of 2.2 μm was used at a weight ratio of / 35/5. Table 1 shows the evaluation results.

Example 4 Agent AB was methyl methacrylate / divinylbenzene / styrene / hydroxypropyl methacrylate = 20/5
Example 1 was repeated except that 0.3 part by weight of crosslinked polymer particles having an average particle diameter of 2.2 μm was used at a weight ratio of / 70/5. Table 1 shows the evaluation results. As can be seen from Table 1, as compared with Examples 1 to 3 using a crosslinked polymer having a methyl methacrylate content in the range of 50 to 95 parts by weight, the initial specific surface resistivity and the embossment were the same, but the haze was the same. Was bad.

Example 5 Example 3 was repeated except that the AB agent was 0.12 parts by weight of crosslinked polymer particles having an average particle diameter of 2.2 μm at a weight ratio of methyl methacrylate / divinylbenzene / hydroxypropyl methacrylate = 90/5/5. Same as Example 1. Table 1 shows the evaluation results.

Comparative Example 1 Sylysia 7 having an average particle diameter of 3.0 μm as an inorganic AB agent
Example 1 was repeated except that 0.30 part by weight of 30 (manufactured by Fuji Silysia Chemical Ltd.) was used. Table 1 shows the evaluation results.

Example 6 0.05% of Ammostat TM310 as an antistatic agent
The same procedure was performed as in Example 1 except that 0.15 parts by weight of Rikemar-100A was used. Table 1 shows the evaluation results.

Example 7 0.20 of Ammostat TM310 as an antistatic agent
The same procedure as in Example 1 was carried out except that 0.5 part by weight of Rikemar-100A was used. Table 1 shows the evaluation results.

Comparative Example 2 Aromastat TM310 0.02 was used as an antistatic agent.
The same procedure as in Example 1 was carried out except that 0.05 part by weight of Rikemar-100A was used. Table 1 shows the evaluation results.

Comparative Example 3 0.40 of Ammostat TM310 was used as an antistatic agent.
The same procedure as in Example 1 was performed except that 1.0 part by weight of Rikemar-100A was used. Table 1 shows the evaluation results.

[0040]

[Table 1]

[0041]

EFFECTS OF THE INVENTION By using an antiblocking agent, which is the polymer compound particles of the present invention, and an antistatic agent together, the transparency, antiblocking property and scratch resistance of the molded product are good, and it is possible to improve the transparency in the initial stage after film formation. A polypropylene resin composition capable of giving a film having good antistatic properties is obtained, which is industrially superior.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location C08L 33:08) B29K 23:00 (72) Inventor Tadashi Asanuma 1-6 Takasago, Takaishi-shi, Osaka Mitsui Toatsu Inside Chemical Co., Ltd.

Claims (3)

[Claims] 1. A polypropylene resin composition for an extruded film, comprising a crystalline polypropylene, an antistatic agent and an antiblocking agent, wherein 0.10 to 1.0 part by weight of the antistatic agent is added to 100 parts by weight of the crystalline polypropylene. , An anti-blocking agent which is an organic polymer compound particle having an average particle diameter of 1 to 10 μm and having a crosslinked structure is added in an amount of 0.01 to 0.
A polypropylene resin composition for an extruded film, comprising 5 parts by weight. 2. Organic polymer compound particles are composed of a compound having two or more radically polymerizable double bonds in the molecule and at least one compound selected from acrylic acid ester and methacrylic acid ester. The composition according to claim 1, which is a coalesced product and has a content of acrylic acid ester and / or methacrylic acid ester in the polymer of 50 to 95 parts by weight. 3. A film having an initial surface resistivity of 1 × 10 ¹³ Ω or less, which is obtained by extrusion molding the polypropylene resin composition for an extruded film according to claim 1.