JPH08217924A - Polyolefin resin composition - Google Patents

Abstract

PURPOSE: To obtain a polyolefin resin composition excellent in transparency, colorability and processing stability by mixing a polyolefin resin with a specified organic phosphite compound, a specified sorbitol compound and a specified Al compound. CONSTITUTION: This polyolefin resin composition is obtained by mixing 100 pts.wt. polyolefin resin with 0.001-5 pts.wt. organic phosphite compound (A) of formula I (wherein R1 is t-butyl or t-amyl; R2 is 1-8C alkyl; and R3 is H or 1-8C alkyl), 0.001-5 sorbitol compound (B) of formula II (wherein R4 is H, halogen, 1-8C alkyl, alkoxy or OH; 1 is 0 or 1; and m and n are each 0-5) and 0.001-5 pts.wt. Al compound (C) selected from among a basic inorganic Al compound and an Al salt of an 8-30C aliphatic carboxylic acid. This composition is freed from an antagonism effect caused by use of both of compounds A and B by addition of compound C, and therefore it is markedly excellent in stability and transparency.

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 more specifically, it contains a diarylpentaerythritol diphosphite compound, a sorbitol compound and a specific aluminum compound, and has transparency, coloring property,
The present invention relates to a polyolefin resin composition having excellent processing stability.

[0002]

2. Description of the Related Art Polyolefin resins such as polyethylene and polypropylene have excellent mechanical strength,
Due to its properties such as chemical resistance, it is used as films, sheets or various molded products. However, these polyolefin resins have a drawback that they are inferior in stability during high temperature processing or under severe use conditions, resulting in deterioration of physical properties,
It is known to be colored.

It is known to use an organic phosphite compound in order to improve the stability at the time of high temperature processing or under severe usage conditions, and in particular, the diarylpentaerythritol diphosphite compound is highly effective. Are known.

Further, the polyolefin resin is generally insufficient in transparency, and it is necessary to improve the transparency by using various nucleating agents in order to use it for food packaging films, clothes cases and the like. As the nucleating agent, aluminum-pt-butylbenzoate, aromatic phosphoric acid ester metal salt, amino acid metal salt, sorbitol compound, and the like are known. In particular, the sorbitol compound exhibits an excellent effect in improving transparency. It is known.

It is expected that a polyolefin resin composition having excellent processing stability and transparency will be provided by adding a phosphorus antioxidant and a sorbitol compound to the polyolefin resin, and JP-A-63-95246 and Japanese Patent Application Laid-Open No. 1-38454 proposes to use a phosphorus-based antioxidant and a sorbitol compound in combination with polypropylene.

However, when the above-mentioned diarylpentaerythritol diphosphite compound and the sorbitol compound are used in combination, an improvement effect is observed in the processing stability and transparency of the polyolefin resin, but they are compared with each other. As a result, the improvement effect was small, and it was not possible to achieve both processing stability and transparency sufficiently. As described above, since the diarylpentaerythritol diphosphite compound and the sorbitol compound have an antagonistic action, it is not possible to obtain a product having both stability and transparency with these combinations, and the diarylpentaerythritol diphosphite compound cannot be obtained. It has been strongly desired to prevent the antagonism of the combined use of a sorbitol compound and a sorbitol compound.

JP-A-60-90238 proposes to use a sorbitol compound, a phosphite compound and a catalyst deactivator such as hydrotalcite together with a polypropylene resin having a catalyst residue. As the compound, only a compound that shows no or little antagonistic action with the sorbitol compound is described, and the specific diarylpentaerythritol diphosphite compound of the present invention is not specifically described, but is specified as the sorbitol compound. No mention is made of the antagonism of the diarylpentaerythritol diphosphite compound. Further, as the catalyst deactivator, a compound such as calcium stearate containing an aluminum compound may be used, and it is not suggested that the aluminum compound suppresses the antagonistic action.

Further, in JP-A-61-133251 and JP-A-1-20249, it is possible to improve the stability of a polyolefin resin by using a pentaerythritol diphosphite compound in combination with hydrotalcites. However, it is not specifically described that the specific sorbitol compound of the present invention is used in combination, and the prevention of the antagonism of the phosphite compound and the sorbitol compound by the hydrotalcites is also completely avoided. Not listed.

[0009]

[Means for Solving the Problems] In view of the present situation, the present inventors have made diligent studies to find a third component that prevents an antagonistic action when a diarylpentaerythritol diphosphite compound and a sorbitol compound are used in combination. As a result, they have found that the antagonism can be prevented without adversely affecting other properties when a specific aluminum compound is used in combination, and have reached the present invention.

That is, the present invention relates to a polyolefin resin 10
0 to 5 parts by weight of (a) 0.001 to 5 parts by weight of the organic phosphite compound represented by the following general formula (I), and (b) 0.001 of the sorbitol compound represented by the following general formula (II).
1-5 parts by weight and (c) 0.001-5 parts by weight of a basic inorganic aluminum compound and 0.001-5 parts by weight of at least one aluminum compound selected from aluminum salts of aliphatic carboxylic acids having 8 to 30 carbon atoms. It is to provide things.

[0011]

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[0012]

[Chemical 4]

The synthetic resin composition of the present invention will be described in detail below.

In the above general formula (I) used in the present invention, the number of carbon atoms represented by R ₂ and R ₃ is 1
Examples of the alkyl group of ~ 8 include methyl, ethyl,
Propyl, isopropyl, butyl, isobutyl, tert-butyl, amyl, tert-amyl, octyl, isooctyl,
Examples thereof include tertiary octyl and the like, and a compound having an alkyl group having 1 to 5 carbon atoms is particularly preferable.

Therefore, specific examples of the organic phosphite compound represented by the above general formula (I) include, for example, bis (2,4-ditertiarybutylphenyl) pentaerythritol diphosphite and bis (2-second). Tributyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-ditertiary amylphenyl) pentaerythritol diphosphite, bis (2,4-ditertiary butyl-5-
Methylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2-
Tert-Butyl-4,6-dimethylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis (2,4,6-tri-tertiary Butylphenyl)
Pentaerythritol diphosphite, bis (2,6-
Examples include ditertiary amyl-4-methylphenyl) pentaerythritol diphosphite.

These compounds correspond to polyolefin resin 1
0.001 to 5 parts by weight, preferably 0.
01 to 3 parts by weight are added. If the addition amount is less than the above range, the effect of improving stability is insufficient, and if the addition amount is more than the above range, the effect is not improved any more and is wasted.

In the above general formula (II), the alkyl group having 1 to 8 carbon atoms represented by R ₄ is, for example, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl or tert-butyl. , Pentyl, tertiary pentyl, hexyl, heptyl, octyl, isooctyl, tertiary octyl, 2-ethylhexyl and the like, and the alkoxy group includes methoxy, ethoxy, propoxy, isopropoxy, butoxy, tertiary butoxy, pentaoxy, octyl. Oxy etc. are mentioned. Halogen atoms include chlorine and bromine.

Therefore, specific examples of the sorbitol compound represented by the above general formula (II) are, for example, 1,3,2
4-dibenzylidene sorbitol, 1-3-benzylidene-2,4-p-methylbenzylidene sorbitol,
1.3-benzylidene-2,4-p-ethylbenzylidenesorbitol, 1.3-p-methylbenzylidene-2
-4-benzylidene sorbitol, 1-3-p-ethylbenzylidene-2,4-benzylidene sorbitol, 1
-3-p-methylbenzylidene-2,4-p-ethylbenzylidene sorbitol, 1.3-p-ethylbenzylidene-2,4-p-methylbenzylidene sorbitol,
1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p-ethylbenzylidene) sorbitol, 1,3,2,4-di (pn-propylbenzylidene) ) Sorbitol, 1,3,2,4-di (p-i-propylbenzylidene) sorbitol, 1
3,2,4-di (pn-butylbenzylidene) sorbitol, 1,3,2,4-di (ps-butylbenzylidene) sorbitol, 1,3,2,4-di (pt-) Butylbenzylidene) sorbitol, 1,3,2,4-di (2 ', 4'-dimethylbenzylidene) sorbitol,
1,3,2,4-di (p-methoxybenzylidene) sorbitol, 1,3,2,4-di (p-ethoxybenzylidene) sorbitol, 1,3-benzylidene-2,4-
p-Chlorobenzylidene sorbitol, 1.3-p-Chlorobenzylidene sorbitol-2,4-benzylidene sorbitol, 1.3-p-Chlorobenzylidene sorbitol-2,4-p-methyl benzylidene sorbitol, 1.3-p-Chlorobenzylidene- 2,4-p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-p-
Examples thereof include chlorobenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol, and 1,3,2,4-di (p-chlorobenzylidene) sorbitol.

These compounds correspond to polyolefin resin 1
0.001 to 5 parts by weight, preferably 0.
01 to 3 parts by weight are added. If the added amount is less than the above range, the effect of improving transparency is insufficient, and if the added amount is more than the above range, the effect is not improved any more and is wasted. The ratio of these compounds to the organic phosphite compound is not particularly limited, but generally 0.5 to 20 times the weight of the organic phosphite compound is used.

The aluminum compound used in the present invention is selected from basic inorganic aluminum compounds and aluminum salts of aliphatic carboxylic acids having 8 to 30 carbon atoms. Here, the basic inorganic aluminum compound is an inorganic aluminum compound having an ability to adsorb an acidic substance, and examples thereof include aluminum oxide, aluminum hydroxide, aluminum carbonate, and hydrotalcites represented by the following formula, It can be used regardless of the particle size and the presence or absence of crystal water. Further, as the aluminum salt of an aliphatic carboxylic acid, for example, carbon such as octylic acid, neooctylic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, ricinoleic acid, behenic acid, and triacontanoic acid. Examples thereof include aluminum salts of aliphatic carboxylic acids having 8 to 30 atoms, and these may be basic or neutral salts.

[0021]

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These aluminum compounds are added in an amount of 0.001 to 5, preferably 0.01 to 3 parts by weight, based on 100 parts by weight of the polyolefin resin. In particular, the total amount of the above organic phosphite compound and sorbitol compound is added. On the other hand, it is preferable to add 20 to 300% by weight. If the amount added is less than the above range of addition to the polyolefin resin, the effect of preventing antagonism will be insufficient, and addition of more than the above range will not improve the effect any more and will be wasted.

As the polyolefin resin used in the present invention, for example, high density, low density and linear low density polyethylene, isotactic and syndiotactic polypropylene, polybutene-1, poly-3-methyl-
Examples include α-olefin homopolymers and copolymers such as 1-pentene, poly-4-methyl-1-pentene, ethylene-vinyl acetate copolymers, ethylene-propylene random and block copolymers.

The definition of the polyolefin resin in the present invention is broad, and for example, an elastomer such as an ethylene-propylene copolymer elastomer, an ethylene-propylene-ethylidene norbornene copolymer elastomer, or a mixture of these and another thermoplastic resin is also included in the present invention. Included in polyolefin resin.

In the present invention, the component (a) is prepared by adding the organic phosphite compound as the component (a), the sorbitol compound as the component (b) and the aluminum compound as the component (c) to the above polyolefin resin. While improving the stability and transparency while preventing the antagonism of the component (b) and (b), other conventional additives can be added together therewith.

Particularly preferred as these additives are phenol-based antioxidants, thioether-based antioxidants, phosphorus-based antioxidants other than the component (a) of the present invention, ultraviolet absorbers,
Examples thereof include hindered amine light stabilizers.

Examples of the above-mentioned phenolic antioxidant include 2,6-di-tert-butyl-4-methylphenol, stearyl- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, distearyl- (3,5-di-tert-butyl-4-hydroxybenzyl) phosphonate,
2-tert-butyl-4-methyl-6- (2-acryloyloxy-3-tert-butyl-5-methylbenzyl) phenol, thiodiethylenebis [(3,5-ditert-butyl-
4-hydroxyphenyl) propionate], 1,6-
Hexamethylene bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,6-hexamethylene bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionamide], 3,5-Dioxaoctane-1,8-diylbis (3-tert-butyl-4-
Hydroxy-5-methylphenyl) propionate),
3,9-Bis [1,1-dimethyl-2-((3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxyethyl)]-2,4,8,10-tetraoxaspiro [5 .5] undecane, 4,4'-thiobis (2-tert-butyl-5-methylphenol), 2,2 '
-Methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 2,2'-ethylidenebis (4,
6-di-tert-butylphenol), 2,2'-ethylidenebis (4-tert-butyl-6-tert-butylphenol),
4,4'-butylidene bis (2-tert-butyl-5-methylphenol), bis [2-tert-butyl-4-methyl-
6- (2-hydroxy-3-tert-butyl-5-methylbenzyl) phenyl] terephthalate, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3 , 5-tris (3,5-ditert-butyl-4-hydroxybenzyl) isocyanurate,
1,3,5-tris (2,6-dimethyl-3-hydroxy-5-tert-butylbenzyl) isocyanurate, 1,
3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,
3,5-Tris (3,5-di-tert-butyl-4-hydroxyphenylpropionyloxyethyl) isocyanurate, tetrakis [methylene-3- (3 ', 5'-di-tert-butyl-4-hydroxyphenyl) propionate ] Methane etc. are mentioned.

Examples of the thioether antioxidant include dialkylthiodipropionate compounds such as dilauryl thiodipropionate, dimyristyl and distearyl, and polyols such as tetrakis [methylene (3-dodecylthio) propionate] methane. A β-alkyl mercaptopropionic acid ester compound may be mentioned.

Examples of phosphorus antioxidants other than the above-mentioned component (a) include, for example, tris (nonylphenyl) phosphite, tris (2,4-ditert-butylphenyl) phosphite, octyldiphenylphosphite, Di (tridecyl) phenyl phosphite, tetra (tridecyl) bisphenol A diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane triphosphite, 2, 2'-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, tetrakis (2,4-
Examples include ditertiary butylphenyl) biphenylene diphosphonite.

Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone and 2-hydroxy-.
2-hydroxybenzophenone compounds such as 4-octoxybenzophenone and 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone); 2- (2-hydroxy-5-methylphenyl) benzotriazole,
2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-3,
5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-
Methylphenyl) -5-chlorobenzotriazole, 2
-(2-Hydroxy-3-tert-butyl-5-carboctoxyethylphenyl) benzotriazole, 2- (2
-Hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole, 2,2'-methylenebis (4-tertiaryoctyl-6-benzotriazolyl) 2-hydroxyphenylbenzotriazole compounds such as phenol); 2,4-diphenyl-6- (2-hydroxy-4)
-Methoxyphenyl) -s-triazine, 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-octoxyphenyl) -s-triazine and other triazine compounds; phenyl salicylate, resorcinol mono Benzoate, 2,4-ditert-butylphenyl-3,5
-Di-tert-butylbenzoate, hexadecyl-3,5-
Benzoate compounds such as ditertiary butyl benzoate; 2
-Ethyl-2'-ethoxyoxanilide, 2-ethoxy-4'-dodecyloxanilide and other substituted oxanilide compounds; ethyl-α-cyano-β, β-diphenylacrylate, methyl-α-cyano-β-methyl -Β- (p-
Examples include cyanoacrylate compounds such as methoxyphenyl) acrylate.

Examples of the hindered amine light stabilizer include, for example, 2,2,6,6-tetramethyl-4-
Piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, N- (2,2,
6,6-Tetramethyl-4-piperidyl) dodecyl succinimide, 1-[(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] -2,
2,6,6-tetramethyl-4-piperidyl- (3,5
-Di-tert-butyl-4-hydroxyphenyl) propionate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) Sebacate, screw (1,
2,2,6,6-pentamethyl-4-piperidyl) -2
-Butyl-2-3,5-di-tert-butyl-4-hydroxybenzylmalonate, N, N'-bis (2,2,6,6
-Tetramethyl-4-piperidyl) hexamethylenediamine, tetra (2,2,6,6-tetramethyl-4-piperidyl) butane-1,2,3,4-tetracarboxylate, tetra (1,2,2) , 6,6-Pentamethyl-
4-piperidyl) butane-1,2,3,4-tetracarboxylate, bis (2,2,6,6-tetramethyl-
4-piperidyl) -di (tridecyl) butane-1,2,
3,4-tetracarboxylate, bis (1,2,2,
6,6-Pentamethyl-4-piperidyl) -di (tridecyl) butane-1,2,3,4-tetracarboxylate, 3,9-bis [1,1-dimethyl-2- (tris (2,2,2 6,6-Tetramethyl-4-piperidyloxycarbonyl) butylcarboxy) ethyl] -2,4
8,10-tetraoxaspiro [5.5] undecane,
3,9-bis [1,1-dimethyl-2- (tris (1,
2,2,6,6-Pentamethyl-4-piperidyloxycarbonyl) butylcarboxy) ethyl] -2,4
8,10-tetraoxaspiro [5.5] undecane,
1,5,8,12-Tetrakis [4,6-bis (N-
(2,2,6,6-tetramethyl-4-piperidyl)-
N-Butylamino) -s-triazin-2-yl]-
1,5,8,12-tetraazadodecane, 1,5,8,
12-tetrakis [4,6-bis (N- (1,2,2
6,6-Pentamethyl-4-piperidyl) -N-butylamino) -s-triazin-2-yl] -1,5,8,
12-tetraazadodecane, 2-tertiary octylamino-
4,6-dichloro-s-triazine / N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, 1- (2-hydroxyethyl) -2,2 , 6,6-Tetramethyl-4-piperidinol / dimethyl succinate condensate, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine / dibromoethane condensate, etc. Can be mentioned.

In addition, if necessary, bis (4-tert-butylphenyl) phosphate alkali metal salt, 2,2 '
-Methylenebis (4,6-di-tert-butylphenyl) phosphate Alkali metal salt, nucleating agent such as aluminum bis (4-tert-butylbenzoate); Calcium stearate, zinc stearate, etc. Higher alcohols such as; heavy metal deactivators; plasticizers; epoxy compounds; foaming agents; antistatic agents; flame retardants;
A filler, a colorant, a lubricant and the like can be added.

The present invention comprises the component (a) of the present invention,
The component (b), the component (c) and, if necessary, the above-mentioned other components are added to the polyolefin resin,
The addition method is not particularly limited, a method of individually adding each additive to the polyolefin resin, a method of adding each additive to the synthetic resin as a mixture or a high concentration of the additive in advance called a masterbatch Any of the methods of preparing the polyolefin resin composition contained in the above and adding it to the polyolefin resin can be adopted.

Further, the polyolefin resin composition of the present invention is not limited by its processing method, and can be formed into a sheet, a film or a fiber by a known processing method such as extrusion processing, calender processing, injection molding, blow molding or inflation molding. It can be processed into various molding materials.

[0035]

The present invention will be described in more detail with reference to the following examples. However, the invention is not limited by these examples.

Example 1 Polypropylene homopolymer 1
To 100 parts by weight of tetrakis [methylene-3-
(3 ', 5'-di-tert-butyl-4-hydroxyphenyl) propionate] methane 0.1 part by weight, dilaurylthiodipropionate 0.2 part by weight, and bis (2,6-di-diene) as an organic phosphite compound. Tert-butyl-4-methylphenyl) pentaerythritol diphosphite 0.1
Parts by weight, as the nucleating agent sorbitol compound, 1,3,2
-0.5 parts by weight of 4-dibenzylidene sorbitol and the aluminum compound shown in Table 1 were added and mixed by a raker. After that, extrusion processing was repeated at 280 ° C., and changes in the melt flow rate (MFR) at the first extrusion processing and the fifth extrusion processing (fifth time / first time) were measured. Moreover, the haze value of the composition of the first extrusion process was measured. For comparison, the case where the organic phosphite compound was changed to distearyl pentaerythritol diphosphite (Comparative compound 1) and the nucleating agent was changed to aluminum-pt-butylbenzoate (Comparative compound 2). Also conducted a similar test. The results are shown in Table-1.

In polypropylene, the main chain is cleaved at the time of processing to increase the MFR. Therefore, when the change in MFR is close to 1, the processing stability is excellent. A smaller haze value is preferable, and a smaller haze value indicates better transparency.

[0038]

[Table 1]

Example 2 Polypropylene homopolymer 1
To 100 parts by weight of tetrakis [methylene-3-
(3 ', 5'-di-tert-butyl-4-hydroxyphenyl) propionate] methane 0.1 part by weight, dilaurylthiodipropionate 0.2 part by weight, and bis (2,6-di-diene) as an organic phosphite compound. Tert-butyl-4-methylphenyl) pentaerythritol diphosphite 0.1
Parts by weight, 0.3 parts by weight of anhydrous aluminum oxide and Table-
0.5 part by weight of the nucleating agent described in 2 was added and mixed by a raker machine. Then, extrusion processing at 280 ° C. was repeatedly performed, and the change in MFR and the haze value were measured in the same manner as in Example 1. The results are shown in Table-2.

[0040]

[Table 2]

Example 3 With respect to 100 parts by weight of high-density polyethylene resin (Hi-Zex 2200J (density 0.965): manufactured by Mitsui Petrochemical Co., Ltd.), stearyl-3-
0.1 parts by weight of (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,2,4-di (p-
0.3 parts by weight of methylbenzylidene) sorbitol, 0.3 parts by weight of aluminum oxide and 0.2 parts by weight of the organic phosphite compound shown in Table 3 were added and mixed with a Henschel mixer at 1100 rpm for 3 minutes. After making pellets with a single screw extruder at 230 ℃, 150 ℃ × 180
A 1 mm-thick test piece was prepared by compression molding for Kg / cm ² × 5 minutes.

A test piece obtained by compression-molding MFR using the produced pellets was kept in a thermo-hygrostat having a relative humidity of 100% × 40 ° C. for 7 days, and then the presence or absence of bloom was observed by observing the surface with a microscope. Evaluation was made on a scale of 5 (1 has no bloom, 3 has partial bloom, and 5 has full bloom). In addition, the presence or absence of the odor of aldehyde produced by the decomposition of the sorbitol compound was determined by the pellet 20
g was put in a sample bottle, and after 60 hours at 60 ° C., it was measured by an average value of a 5-step evaluation (1 is odorless, 3 is a slight aldehyde odor, and 5 is a strong aldehyde odor) by 10 testers. The results are shown in Table-3.

Since polyethylene causes cross-linking during processing to lower the MFR, a change in MFR closer to 1 indicates better processing stability.

[0044]

[Table 3]

As is clear from the results of the respective examples, the diarylpentaerythritol diphosphite compound, which is the component (a) of the present invention, is a stabilizer that prevents deterioration of the resin under severe conditions such as during processing. Great effect,
Further, the sorbitol compound as the component (b) has a large transparency improving effect, but when both are used in combination, both the stabilizing effect and the transparency improving effect are significantly reduced.

Such a phenomenon (antagonism) is hardly observed when an organic phosphite compound other than the component (a) and / or a nucleating agent other than the component (b) is used.
This is a very specific phenomenon that appears only when the components (a) and (b) of the present invention are used together.

Further, when an organic phosphite compound other than the component (a) and / or a nucleating agent other than the component (b) is used, even if the specific aluminum compound as the component (c) is used in combination, its stability is improved. Although the curing effect and the transparency are hardly improved, when the components (a), (b) and (c) are used in combination, the components (a) and (b)
It is clear that the antagonism when the components are used in combination is prevented, and it is clear that the effect of the combination of the present invention is extremely remarkable and specific.

[0048]

Effects of the Invention By adding an organic phosphite compound represented by the general formula (I), a sorbitol compound represented by the general formula (II) and a specific aluminum compound to a polyolefin resin, the organic phosphite compound and sorbitol are added. It is possible to obtain a polyolefin resin composition which prevents the antagonistic action of a compound and is excellent in stability and transparency.

Claims (2)

[Claims] 1. To 100 parts by weight of a polyolefin resin, (a) 0.001 to 5 parts by weight of an organic phosphite compound represented by the following general formula (I), and (b) the following general formula (I)
0.001 to 5 parts by weight of the sorbitol compound represented by I) and at least one aluminum compound selected from (c) basic inorganic aluminum compounds and aluminum salts of aliphatic carboxylic acids having 8 to 30 carbon atoms.
A synthetic resin composition containing 001 to 5 parts by weight. Embedded image Embedded image 2. The synthetic resin composition according to claim 1, wherein the basic inorganic aluminum compound is aluminum hydroxide, aluminum oxide or hydrotalcites.