JPH0762162A - Polyolefin resin composition and film - Google Patents

Abstract

PURPOSE:To provide a polyolefin resin compsn. which is excellent in heat resistance, resistance to yellowing during long storage, prevention of metal corrosion, prevention of resinous deposit during processing, and heat sealbility. CONSTITUTION:The title compsn. comprises a polyolefin resin, a phosphorus compd. of the formula wherein R1, R2, and R3 are each a 1-4C hydrocarbon group provided they may be the same or different from each other, a hydrotalcite compd., an antiblocking agent, and a lubricant and/or a surfactant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin resin composition and a film molded therefrom, and particularly to color stability, heat stability, corrosion resistance, blocking property, antistatic property, antifogging property, heat sealing property and the like. Of improved polyolefin compositions and films formed therefrom.

[0002]

2. Description of the Related Art Recently, in order to reduce the cost of a plastic film, the molding speed has been increased and the product has been made thinner. In order to cope with these, the film forming temperature tends to be set higher than in the past. Further, since linear low-density polyethylene has strength even if it is thin, and has excellent heat-sealing properties, it has been widely used as a sealant film in place of branched low-density polyethylene. However, since linear low-density polyethylene has a high viscosity during processing, it must be molded at a higher temperature than branched low-density polyethylene. In this case, the problem is that continuous operation becomes impossible due to heat deterioration of the resin, appearance failure due to fish eye formation, blocking caused by winding the film without being sufficiently cooled, and thinning. In addition, the effects of lubricants, antistatic agents, antifogging agents, etc. may not be fully exhibited.

For this reason, various antioxidants have been widely used for the purpose of preventing thermal deterioration during molding, but polyolefins containing these additives, especially phenolic antioxidants, are It has the drawback of turning yellow after long-term storage. Also, to prevent deterioration during high temperature processing,
A method of adding a phosphorus-containing compound such as phosphite has been proposed (for example, Japanese Examined Patent Publication No. 62-4418). However, a phosphorus compound having a good antioxidation performance is still not sufficient, because it has drawbacks such as being easily absorbed by moisture and difficult to handle, and is likely to cause metal corrosion, and improvement has been desired. Further, depending on the phosphorus compound, the compatibility with the polyolefin is poor, so that it may be leached on the surface and whitened on the surface of the film to deteriorate the transparency.

Various oxides are used to prevent blocking, and those having a large blocking effect deteriorate the transparency of the film, and addition of zeolite is known as an oxide which maintains the transparency relatively. Although it has been described (for example, Japanese Patent Application Laid-Open No. 61-101543), it has a drawback that it has a hygroscopic property and thus produces eye grease during processing.

[0005]

DISCLOSURE OF THE INVENTION The present invention prevents yellowing and high speed during long-term storage due to chemical action of light, oxygen, etc., deterioration during heating at high temperature processing and generation of eye grease, and metal corrosion resistance. It is an object of the present invention to provide a reduced polyolefin composition and to provide a film having less blocking, excellent opening properties, and heat sealing properties.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the present situation, the present inventors have found that a phosphorus compound represented by the following general formula, a hydrotalcite compound, and a blocking agent can be applied to a polyolefin resin. By adding an inhibitor and a lubricant and / or a surfactant, a polyolefin resin composition with excellent heat resistance, prevention of yellowing during long-term storage, prevention of metal corrosion, prevention of eye grease during processing, heat sealability, etc. I found that I could get things.

That is, the present invention relates to "a polyolefin resin, (A) a phosphorus compound represented by the following general formula, and (B)
A polyolefin resin composition obtained by adding at least one selected from the group consisting of hydrotalcites, (C) antiblocking agent and (D) lubricant and surfactant. General formula:

[0008]

[Chemical 2]

[Wherein R ₁ , R ₂ and R ₃ are the same or different hydrocarbon groups having 1 to 4 carbon atoms]. ].

The present invention will be described in detail below. The polyolefin of the present invention includes ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene-1,
Homopolymers of α-olefins such as 1-octene or their interpolymers, ethylene-vinyl ester copolymers such as ethylene-vinyl acetate copolymers, ethylene-unsaturated carboxylic acids or their derivative copolymers, or their copolymers. There are mixtures, etc. Although it is not particularly limited as long as it is a polyolefin, particularly remarkable effects can be obtained when a polyolefin that is polymerized with a Ziegler-based highly active catalyst and has not undergone a catalyst removal step is used.

The Ziegler-based highly active catalyst comprises a solid catalyst component containing at least magnesium and titanium and an organoaluminum compound. Examples of the solid catalyst component include metal magnesium; magnesium hydroxide; magnesium oxide; magnesium salts such as magnesium chloride; silicon, aluminum, calcium; double salts and double oxides containing an element selected from magnesium, magnesium carbonate and magnesium atoms; Carbonates, chlorides, hydroxides, etc .; and inorganic solid compounds containing magnesium such as those obtained by treating or reacting these inorganic solid compounds with oxidative compounds, sulfur-containing compounds, aromatic hydrocarbons, halogen-containing substances In addition, a titanium compound supported by a known method may be mentioned.

Examples of the above oxygen-containing compounds include water; organic oxygen-containing compounds such as alcohols, phenols, ketones, aldehydes, carboxylic acids, esters, polysiloxanes and acid amides; inorganic substances such as metal alkoxides and metal oxychlorides. Examples of the system oxygen-containing compound can be given.

Examples of the sulfur-containing compound include organic sulfur-containing compounds such as thiol and thioether, and inorganic sulfur compounds such as sulfur dioxide, sulfur trioxide and sulfuric acid. As aromatic hydrocarbons, benzene, toluene,
Examples thereof include various monocyclic and polycyclic aromatic hydrocarbon compounds such as xylene, anthracene, and phenanthrene. Examples of the halogen-containing substance include compounds such as chlorine, hydrogen chloride, metal chlorides and organic halides. On the other hand, examples of the titanium compound supported on the inorganic solid compound containing magnesium include titanium halides, alkoxy halides, alkoxides, and halogenated oxides. As the titanium compound, a tetravalent titanium compound and a trivalent titanium compound are preferable, and as the tetravalent titanium compound, specifically, the general formula Ti (OR) _n X _4-n (where R is a carbon number 1 To 20 alkyl groups, aryl groups or aralkyl groups, X represents a halogen atom, and n is an integer of 0 ≦ n ≦ 4), titanium tetrachloride,
Titanium tetrabromide, titanium tetraiodide, monomethoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxymonochlorotitanium, tetramethoxytitanium, monoethoxytrichlorotitanium, diethoxydichlorotitanium, triethoxymonochlorotitanium, tetraethoxytitanium, monoisopropoxy. Trichlorotitanium, diisopropoxydichlorotitanium, triisopropoxymonochlorotitanium,
Examples thereof include tetraisopropoxy titanium, monobutoxy trichloro titanium, dibutoxy dichloro titanium, monopentoxy trichloro titanium, monophenoxy trichloro titanium and tetraphenoxy titanium. The trivalent titanium compound is a trihalogenated compound obtained by reducing titanium tetrahalide such as titanium tetrachloride or titanium tetrabromide with hydrogen, aluminum, titanium or an organometallic compound of Group I to III metal of the periodic table. Examples include titanium. Further, the general formula Ti (OR) _m X _4-m (wherein R represents an alkyl group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, X represents a halogen atom, and m represents 0 ≦ m ≦ 4)
A trivalent titanium compound obtained by reducing a tetravalent halogenated alkoxytitanium represented by the formula (1) with an organometallic compound of a metal of Group I to III of the periodic table.

Of these titanium compounds, tetravalent titanium compounds are particularly preferable.

As another example of the catalyst system, a reaction product of an organomagnesium such as a so-called Grignard compound and a titanium compound can be used as a solid catalyst component.

As another example of the catalyst system, a solid substance obtained by contacting the above-mentioned solid catalyst containing at least magnesium and titanium with an inorganic oxide such as SiO ₂ or Al ₂ O ₃ as a solid catalyst component. The thing used can be mentioned.

Specific examples of the organoaluminum compound to be combined with the above solid catalyst component include the general formulas R ₃ Al, R ₂ AlX, RAlX ₂ , R ₂ AlOR, R.
Organoaluminum compounds of Al (OR) X and R ₃ Al ₂ X ₃ (wherein R represents an alkyl group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, X represents a halogen atom, and R is the same or May be different) are preferred, triethyl aluminum, triisobutyl aluminum, trihexyl aluminum,
Examples include trioctylaluminum, diethylaluminum chloride, diethylaluminum ethoxide, ethylaluminum sesquichloride and mixtures thereof.

Although the amount of the organoaluminum compound used is not particularly limited, it is usually 0.1 to 1, relative to the titanium compound.
It can be used in a molar amount of 000.

The polymerization reaction is carried out in the same manner as the polymerization reaction of olefins using a conventional Ziegler type catalyst. That is, all the reactions are carried out in a gas phase or in the presence of an inert solvent or in a liquid phase using the monomer itself as a solvent, in a state where oxygen and water are substantially removed. The polymerization reaction of olefin is usually 20 to 300 ° C., preferably 40 to 200 ° C., and the pressure is normal pressure to 70 kg / cm ² G, preferably 2 kg / c.
It is carried out at m ² G to 60 kg / cm ² G. The molecular weight can be adjusted to some extent by changing the polymerization conditions such as the polymerization temperature and the molar ratio of the catalyst, but it is effectively performed by adding hydrogen to the polymerization system. Of course, it is possible to carry out a two-step or more multi-step polymerization reaction with different polymerization conditions such as hydrogen concentration and polymerization temperature without any trouble.

The polyolefin used in the present invention is clearly distinguished from a polyolefin obtained by using a conventional solid catalyst component mainly containing vanadium as a solid catalyst component. Even if both have the same monomers constituting the copolymer and have the same density, the _Tm by DSC is higher in the polyolefin of the present invention. The C ₆ insoluble content is 10% by weight or more in the copolymer of the present invention, whereas when the vanadium-containing catalyst is used, the C ₆ insoluble content is not present or is extremely small.

The phosphorus compound of the present invention has the general formula:

[0022]

[Chemical 3]

It is an organic phosphonite compound represented by:

In the formula, R ₁ , R ₂ , and R ₃ are the same or different hydrocarbon groups having 1 to 4 carbon atoms, and C _n H
An alkyl group represented by _{2n + 1} is preferable, and _{one having} R ₁ or R ₂ having 1 or 4 carbon atoms has excellent hydrolysis resistance and antioxidant performance.

The amount of the above components used in the present invention is usually 0.005 to 100 parts by weight of the polyolefin.
It is 5 parts by weight, preferably 0.01 to 2 parts by weight.

A typical example of the hydrotalcites used in the present invention is a double salt compound represented by the following formula. (M ²⁺ ) _1-x Al _x (OH) ₂ (A ⁿ⁻ ) _{x / n} ·
mH ₂ O (wherein 0 <x ≦ 0.5, m: real number M ^2+: n-valent anion: Mg, Ca or ^{Zn, A n-)} is also used Izure of natural products and synthetic products as the compound but especially ^{M 2+} is ^{Mg, a n-is} _CO ^{3 2-} is a synthetic desirable. The blending amount of the above components used in the present invention is usually 0.
The amount is 01 to 1 part by weight, preferably 0.02 to 0.08 part by weight. By blending this component, the antioxidant performance is greatly and synergistically improved as compared with the case of adding the phosphorus compound alone.

Examples of antiblocking agents for preventing blocking during high speed molding include silicon oxide, amorphous aluminosilicate compounds, talc and metal carbonates.

As the silicon oxide, diatomaceous earth as a raw material is pulverized, classified and then calcined, or synthetic silica produced by neutralizing sodium silicate with an acid, or acid clay is treated with an acid. Amorphous silica, fumed silica produced by a combustion hydrolysis method of silicon halide, and the like are used. The antiblocking effect and the transparency of the film differ depending on the shape and size of the particles. The diatomaceous earth silica, which has a jagged surface on the surface when pulverized, has a large blocking-preventing effect, but conversely has poor transparency. Synthetic silica having a nearly spherical shape can maintain transparency, but tends to cause blocking. The larger the particle size, the greater the blocking effect, but the poorer the transparency. In view of the balance between transparency and blocking, the silica is nearly spherical and has a particle size of 10 μm or less, preferably 2 to
Those having a size of 6 μm are preferably used. The amount used is usually 0.05 to 2.0 parts by weight, preferably 0.1 to 1.0 part by weight, based on 100 parts by weight of the polyolefin.

The crystalline aluminosilicate salt having a zeolite structure has a relatively large antiblocking effect,
It is an anti-blocking agent that is usually used because it maintains transparency, but it has a drawback of foaming during extrusion molding and sticking of die to the die because it contains about 24% of water in the equilibrium state. . It was found that this defect was ameliorated by using an amorphous aluminosilicate compound, and a film having good blocking and transparency was obtained. The amorphous aluminosilicate compound is obtained by subjecting a usual crystalline zeolite to acid treatment and then dehydration by heating, and is substantially amorphous having no crystal peak by X-ray diffraction, It exists as particles having a uniform morphology. The starting crystalline zeolite is A
Type, X type, P type, Y type and the like, and the acid used may be an inorganic acid or an organic acid, but usually hydrochloric acid, sulfuric acid, nitric acid,
Phosphoric acid or the like is used. An acid is added to an aqueous slurry of crystalline zeolite, and it is desirable to neutralize the acid under conditions such that the final pH is 7.0 to 3.0. At pH higher than this range, the alkali in the zeolite is not sufficiently removed,
It becomes an insufficient amorphous aluminosilicate salt, which causes deterioration of the transparency of the film. Further, at a pH lower than this range, the alumina component in the zeolite is eluted and the cubic shape of the particles cannot be maintained, and the blocking effect becomes insufficient. This amorphous aluminosilicate salt is filtered,
An amorphous aluminosilicate salt can be obtained by washing with water, drying or baking. Examples of other amorphous aluminosilicate compounds include P-type crystalline zeolite ion-exchanged with a divalent metal represented by Group II of the periodic table,
Some are obtained by firing. Ion exchange of Na contained in the P-type zeolite with Ca, Mg, Ba, Zn, etc. facilitates amorphization and further reduces hygroscopicity. Therefore, there is less eye blemishes and foaming during extrusion. Further, since it is modified into a weak alkali, the hue of the blended polyolefin becomes stable. Further, this zeolite has a refractive index closer to that of polyolefin as a result of being substituted with a divalent metal, so that the transparency of the film is maintained. The ion exchange treatment is a method of stirring an aqueous divalent metal salt solution, for example, an aqueous solution of chloride or nitrate and P-type zeolite in an aqueous slurry state, or bringing the zeolite into contact with the aqueous metal salt solution in a fixed bed or a fluidized bed. Done by A contact temperature of 30 ° C to 70 ° C is suitable, and the higher the temperature, the shorter the treatment time. The processing time is usually 0.5 to 3 hours. The treated exchanged zeolite is washed with water after solid-liquid separation.
After drying, baking is performed. The calcination temperature is selected at a temperature at which the exchanged zeolite becomes substantially amorphous, and is generally 200 to 70.
Baking at 0 ° C.

The particle size of these amorphous aluminosilicate compounds is usually 10 μm or less, preferably 1 to 5 μm. The blending amount is based on polyolefin
Usually 0.05 to 2.0 parts by weight, preferably 0.1 to 1.
Used in 0 parts by weight.

As talc, natural talc is generally used after being crushed and classified. Since silicon oxide has a high hardness, if it is mixed in a large amount, the film may have fine scratches and white spots, resulting in poor transparency.However, talc is soft and also has slipperiness, so blocking may occur. The effect is large and transparency is maintained. Particle size is 10 μm or less, especially 2-5
Those having a size of μm are preferably used. The compounding amount is usually 0.05 to 3.0 parts by weight, preferably 0.1 to 1.0 part by weight, based on the polyolefin.

As calcium carbonate, limestone is crushed,
Classified so-called heavy calcium carbonate and light calcium carbonate obtained by crushing and burning limestone to produce quick lime, hydrated to make lime milk, and further reacting with carbon dioxide gas generated from the firing furnace. Is usually used. Further, in order to improve the compatibility with the polyolefin, those surface-treated with a fatty acid, a metal soap, a silane coupling agent, a titanate coupling agent or the like may be used. Calcium carbonate slightly deteriorates the surface haze, but since it has a large blocking effect, the compounding amount can be reduced, and therefore the influence on the haze can be suppressed to a low level. It also has the characteristic that vitiligo does not easily occur. It is preferable that the particle size is small, and usually, the particle size is 5 μm or less, preferably 0.05 to 3 μm.
The compounding amount is usually 0.5 to 3.0 parts by weight, preferably 0.
1 to 1.0 parts by weight. The above blocking inhibitors may be used alone or in combination of two or more.

A fatty acid amide is usually used as a lubricant to be added to the film for imparting lubricity. Examples of the fatty acid amide include higher fatty acid amide having 8 to 22 carbon atoms, ethylene bis fatty acid amide having 16 and 18 carbon atoms, stearyl erucamide, oleyl palmitoamide and the like. The selection of these lubricants depends on the molding temperature of the polyolefin. Amide having a low melting point is used for the one having a low molding temperature, and saturated fatty acid amide having a high melting point is used for the one having a high molding temperature. For example, oleic acid amide and the like are preferably used for low density polyethylene, and erucic acid amide and behenic acid amide and the like are preferably used for linear low density polyethylene and polypropylene. The compounding amount is usually 0.02 to 1.0 part by weight, preferably 0.03 to 0.5 part by weight. When the amount is less than 0.02 part by weight, the slipping effect is insufficient and the mouth opening becomes insufficient, and when the amount is more than 1.0 part by weight, blocking tends to occur rather easily due to bleeding after amide.

As the lubricant, fatty acid metal salts, hydroxy fatty acid metal salts and fatty acids can be used, but these are preferably used in combination with the above lubricants. Examples of fatty acid metal salts, hydroxy fatty acid metal salts, and fatty acids include fatty acid metal salts such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid, and lithium, sodium, magnesium, Examples thereof include salts with metals such as calcium and zinc, and calcium stearate is particularly desirable. It is also preferred to use mixtures of these metal salts with fatty acids in order to improve the color stability. Examples of the fatty acid include the above fatty acids, and a mixture of stearic acid and calcium stearate is most preferably used. The amount of the above components used in the present invention is usually 0.05 to 5 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the polyolefin.
2 parts by weight.

The surfactant is added to the polyolefin film to add antistatic property and antifogging property. A nonionic surfactant is preferably used as the surfactant. Specific examples thereof include sorbitan fatty acid ester,
Propylene glycol fatty acid ester, saccharose fatty acid ester, pentaerythritol fatty acid ester, trimethylolpropane fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl Ether, N, N bis (2
-Hydroxyethyl) alkylamine, N, N bis (2
-Hydroxyethyl) alkyl amide, a condensate of a fatty acid and diethanolamine, etc. are exemplified. Examples of the anionic surfactant include alkyl sulfonate, sodium dicyclohexyl sulfosuccinate, polyoxyethylene alkyl phosphate and the like. Examples of the cationic surfactant include quaternary ammonium chloride, and examples of the amphoteric surfactant include alkyl betaine, alkyl imidazoline, and alkyl alanine. These surfactants are usually used in an amount of 0.03 to 1 part by weight, preferably 0.1 to 0.1 parts by weight, based on the polyolefin resin.
~ 0.5 parts by weight are blended. When it is less than 0.03%, the effect is insufficient, and when it is blended in an amount of more than 1 part by weight, the surface bleeding is deteriorated due to excessive surface bleeding. The lubricant and the surfactant may be used alone or in combination.

In the present invention, it is preferable to further improve the thermal stability by adding a phenol type antioxidant and / or a thioether type antioxidant.

Specific examples of the phenolic antioxidant include 2,6-tert-butyl-4-methylphenol, 2-
Tertiary butyl-4-methoxy-phenol, n-octadecyl-3- (3,5-di-tertiary butyl-4-hydroxyphenyl) propionate, 2,2'-ethylidene-bis (2,4-tertiary butylphenol ), 4,4'-thiobis (3-methyl-6-tert-butylphenol), 1,
3,5, -Trimethyl-2,4,6-tris (3,5,5
-Di-tert-butyl-4-hydroxybenzyl) benzene,
Tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, Tris (4-tert-butyl-)
2,6-Dimethyl-3-hydroxybenzyl) isocyanurate, tetrakis- [methylene-3- (3 ', 5'
-Di-tert-butyl) -4'-hydroxy-phenyl) propionate] methane, 3,9-bis [1,1-di-methyl-2- {β- (3-tert-butyl-4-hydroxy- 5-Methylphenyl) propionyloxy} ethyl]
-2,4,8,10-Tetraoxazaspiro [5,5] undecane, 4,4'-thio-bis- (3-methyl-6-
Tertiary butylphenol) and the like. These antioxidants are usually added in an amount of 0.01 to 0.15 part by weight.

Examples of thioether type antioxidants include dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate and dimyristyl-
Examples include 3,3′-thiodipropionate, pentaerythritol-tetrakis- (β-lauryl-thiopropionate), 2-mercapto-5-methylbenzimidazole and the like. These antioxidants are usually 0.01
~ 0.15 parts by weight are added.

The composition of the present invention further comprises an ultraviolet absorber,
The weather resistance can be improved by adding a light stabilizer such as a hindered amine compound.

Specific examples of the ultraviolet absorber include 2,4-
2-hydroxybenzophenones such as dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone and 5,5'-methylenebis (2-hydroxy-4-methoxybenzophenone), 2- (2 ′ -Hydroxy-5 ′
-Methylphenyl) benzotriazole, 2- (2'-
Hydroxy-5'-tertiary octylphenyl) benzotriazole, 2- (2-hydroxy-3 ', 5'-ditertiary
Butylphenyl) -5-chlorobenzotriazole, 2
-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2,
Benzotriazoles such as 2'-methylenebis (4-tertiary octyl-6-benzotriazol) phenol, resorcinol monobenzoate, 2,4-di-tertiary butylphenyl-3'-5'-ditertiary butyl- Examples thereof include benzoates such as 4'-hydroxybenzoate and hexadecyl-3-5-di-tert-butyl-4-hydroxybenzoate.

The hindered amine type light stabilizers include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1. , 2,3,4-butane tetracarboxylate, bis (1,2,2,6,
6-pentamethyl-4-piperidyl) .di (tridecyl) -1,2,3,4-butanetetracarboxylate, 1- (2-hydroxyethyl) -2,2,6,6-
Polycondensation product of tetramethyl-4-piperidinol and diethyl succinate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane and 2,4-dichloro-6-tertiary octyl Examples thereof include polycondensation products of amino-s-triazine.

In addition, if necessary, the composition of the present invention contains a heavy metal deactivator, a nucleating agent, a metal soap, an acid absorbent, a pigment,
A filler, a plasticizer, an epoxy compound, a foaming agent, a flame retardant, a processing aid, a polar group-containing polyolefin, etc. can be contained.

The film of the present invention can be formed by any conventionally known method, but an air-cooled or water-cooled inflation molding method is preferably used for general-purpose applications such as a dust bag, a shopping bag, a standard bag and a cleaning bag. In the case of molding LLDPE, it is desirable to use a screw exclusively for LLDPE, which suppresses heat generation, instead of the full-flight type screw which is usually used because it has a high viscosity during processing. Further, since the molding temperature is as high as about 200 ° C., it is desirable to attach and mold an air ring that is sufficiently cooled. In the case of LLDPE which is molded at a high temperature and the polypropylene film which is molded by a water cooling method as described above, the composition of the present invention is preferably used because heat resistance is required and blocking is likely to occur.

Further, in the case of forming a raw film for lamination or a wide film, a cast film forming method using a T-die is preferably used. In this case, the composition of the present invention is preferably used in which not only blocking but also the metal roll and the film are attached during molding, which may make it difficult to peel off, and a lubricant which is the component (d).

[0045]

EXAMPLES AND COMPARATIVE EXAMPLES The present invention will be specifically described below based on Examples and Comparative Examples, but the present invention is not limited thereto. The properties were measured in the examples and comparative examples by the following methods.

(Sample) Polyolefin Resin Using a solid catalyst obtained from substantially anhydrous magnesium chloride, 1,2-dichloroethane and titanium tetrachloride and a catalyst consisting of triethylaluminum, ethylene and 1-butene were co-produced. It was polymerized to obtain an ethylene / 1-butene copolymer. This ethylene / α-olefin copolymer has a 1-butene content of 4 mol% and a density of 0.922 g / cm 3.
³ , MFR 2g / 10min.

(Initial Hue) After blending various additives with the polyolefin resin, a press sheet having a thickness of 2 mm was prepared, and its yellowness (according to JISK7103) was measured to obtain the initial hue.

(Color Stability) In a composition containing a phenolic antioxidant, yellowing of pellets or molded products after long-term storage is a practical problem. In Examples in which a phenolic antioxidant was used in combination, an accelerated test was conducted to estimate the degree of yellowing during long-term storage. That is, a press sheet having a thickness of 2 mm prepared from the prepared composition is
After being exposed to a thermo-hygrostat having a temperature of 80 ° C. and a relative humidity of 90% for 2 weeks, the yellowness (according to JIS K7103) was measured.

(Thermal stability) As a measure of thermal stability when the composition was melt-kneaded, the oxygen induction period until thermal deterioration in an oxygen stream was measured. That is, using a differential calorimeter manufactured by Seiko Denshi Kogyo Co., Ltd., a heating rate of 20
° C / min. Then, the temperature was raised to the measurement temperature (200 ° C.), and after reaching the measurement temperature, the time until the electromotive force was rapidly increased after switching to oxygen was measured, and the oxygen induction period was determined.
(Oxygen flow rate 100 ml / min.). A 0.2 mm sheet was prepared by hot pressing from the prepared composition and subjected to measurement.

(Corrosion resistance) A phosphorus compound was placed in a petri dish, an iron piece was left on the powder, and exposed to a constant temperature and humidity bath at a temperature of 30 ° C. and a relative humidity of 90% for a period of time until rust was generated. It was measured.

(Film molding) Using a 50 mm LLDPE dedicated film molding machine, a die with 100 mmφ and a lip gap of 2 mm was attached, and a thickness of 3 was obtained under the following molding conditions.
A 0 μm film was molded. Since it is difficult to form a film with LLDPE alone, MFR 2.0 and density 0.9
22 branched polyethylene (Nisseki polyethylene F31N)
Was blended in an amount of 20% by weight to form a film.

(Evaluation of Film Performance) Optical properties, blocking strength, lubricity and antistatic performance of the film were evaluated by the following methods. Optical properties: Haze measurement by ASTM D1003 Blocking strength: Two films are overlaid, 60 ° C
After forcing to block in the oven for 5 hours, 500 mm / min. The peeling strength due to rubbing was measured at the pulling speed. Lubricity: The coefficient of static friction between the film surfaces was measured. Antistatic performance: Surface resistivity was measured.

Examples 1 to 10 and Comparative Examples 1 to 6 Various additives were dry blended with the additive-free powder of the above polyolefin, and then kneaded by an extruder and pelletized. The additives used in Examples and Comparative Examples are shown below. Component (a): Phosphorus compound in which R1 and R3 are t-butyl groups and R2 is a methyl group Component (c): C-1, amorphous aluminosilicate (Shilton JC-30 manufactured by Mizusawa Chemical Co., Ltd.), C-2 , Diatomaceous earth (John Manville super floss), C-3, talc (Hayashi Kasei Micron White 5000)
S), C-4, calcium carbonate Component (d): D-1, erucic acid amide, D-2, behenic acid amide, D-3, stearic acid monoglyceride, D-4, N, N-bis (2-) Hydroxyethyl) stearylamine Component (e): e-1, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, e-2, dilaurylthiodipropionate Other phosphorus compounds : P-1, tetrakis (2,4-di-t
-Butylphenyl) -4,4'-biphenylenediphosphonite p-2, tris (2,4-di-t-butylphenyl) phosphonite Other antiblocking agents: Z-1, crystalline zeolite (manufactured by Kosei) CS-100)

Example 1 shows an example of using the phosphorus compound of the present invention as the component (a). Comparative Examples 1 to 3 show examples in which P-1 which is another phosphorus compound was added. The compounds of Examples are superior to the Comparative Examples in antioxidant performance and do not generate rust.

Examples 1 and 2 to 4 show examples in which the antiblocking agent of the present invention was added as the component (c).
Comparative Example 2 shows an example not containing the component (c), and Comparative Example 3 shows an example in which a crystalline zeolite which is another antiblocking agent was added as the component (c). In Comparative Example 2 containing no component (c), the film was strongly blocked and did not open at all. Further, in Comparative Example 3 in which zeolite containing 24% water as the equilibrium water content was mixed, the grease was generated during the extrusion, and continuous operation could not be performed. Furthermore, the transparency was excellent,
Blocking occurred. The ones of the examples also have less eye grease,
I'm not blocking either.

Examples 5 to 7 show examples in which a lubricant or a surfactant was blended as the component (d). Example 5 has less blocking, and Examples 6 and 7 containing a surfactant have a smaller surface specific resistance than Comparative Example 1 and have an antistatic effect.

Examples 8 to 10 show examples in which another antioxidant was added as the component (e) to the phosphorus compound of the present invention. Comparative Example 4 shows an example in which only the component e-1 was added. Further, Comparative Examples 5 and 6 show examples in which another phosphorus compound and the component e-1 were added. Comparing Examples 8 to 10 with Comparative Example 4, even if the total amount of antioxidant added is the same,
The combined use of the phosphorus compound and the other antioxidant synergistically improves the antioxidant performance. Further, in Comparative Example 4, the hue changes to yellow with the passage of time and cannot be practically used, but the composition of the Example has a stable color. In Comparative Example 5 in which p-1, which is another phosphorus compound, was added, the antioxidant performance was almost the same as that of the Example, but generation of rust due to hydrolysis was observed. Further, in Comparative Example 6 in which p-2 was added, not only the antioxidative performance was inferior to that in the Examples, but also the film became cloudy and the transparency was poor.

[0058]

[Table 1]

[0059]

[Effect] Heat resistance by blending a specific phosphorus compound, hydrotalcite, an antiblocking agent and a lubricant or a surfactant into the polyolefin as described above,
It is possible to obtain a polyolefin resin composition and a film which are excellent in corrosion resistance, anti-blocking property and the like, do not generate greas during processing, and do not yellow with time.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C08K 5/20 KEW 5/37 KFE 5/5393

Claims (7)

[Claims] 1. A polyolefin resin comprising a group consisting of (A) a phosphorus compound represented by the following general formula, (B) hydrotalcites, (C) an antiblocking agent, and (D) a lubricant and a surfactant. A polyolefin resin composition comprising at least one selected. General formula: [In formula, R < ₁ >, R < ₂ >, R < ₃ > is the same or different C1-C4 hydrocarbon group, respectively. ] 2. The polyolefin resin composition according to claim 1, further comprising at least one selected from the group consisting of (E) a hindered phenol-based antioxidant and a thioether-based antioxidant. 3. The polyolefin resin composition according to claim 1, wherein the polyolefin resin is polymerized by using a highly active Ziegler catalyst and has not undergone a deashing step. 4. The antiblocking agent is silicon oxide,
2. At least one selected from the group consisting of amorphous aluminosilicate compounds, talc and carbonates.
4. The resin composition according to any one of 3 to 3. 5. The polyolefin resin composition according to claim 1, wherein the lubricant contains fatty acid amide as an essential component. 6. The polyolefin resin composition according to claim 1, wherein the surfactant is a nonionic surfactant. 7. A film molded using the resin composition according to claim 1.