JP2006176706A - Thermoplastic resin composition and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the hydrolysis resistance of a thermoplastic resin composition comprising a thermoplastic resin and a phosphorous type antioxidant. <P>SOLUTION: The thermoplastic resin composition contains the following (A)-(D) and contains, based on 100 pts.wt. of the thermoplastic resin (A), 0.001-1 pt.wt. of the antioxidant (B), 0.001-5 pts.wt. of an inorganic antiblocking agent(C) and 0.001-1 pt.wt. of a neutralizer (D). Herein, the (B) is an antioxidant having at least a phosphite structure or a phosphonite structure in the molecule, the (C) is an inorganic antiblocking agent whose amount of solid acids exceeds 100 μmol/g, and the (D) is at least one neutralizer selected from the group consisting of hindered piperidine compounds, carboxylic acid amide compounds, hydrotalcites, metal hydroxides and carboxylic acid metal salts. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermoplastic resin composition containing a thermoplastic resin, an antioxidant, an inorganic antiblocking agent and a neutralizing agent, and a method for producing the same.

Patent Document 1 describes a thermoplastic resin composition containing a polyethylene resin, an antioxidant having a phosphite structure and a hindered phenol structure in the same molecule, and an inorganic antiblocking agent such as aluminosilicate or kaolin. Has been.
Patent Document 2 discloses that 100 parts by weight of a polyolefin-based resin; vacuum-dried at 120 ° C. for 2 hours, and allowed to cool to room temperature in a silica gel desiccator; Into the flask, 40 ml of dehydrated toluene was added, and the inside of the flask was replaced with dry nitrogen gas. Then, an 11 vol% toluene solution of triethylaluminum was added with stirring, and the reaction was caused by the reaction between the —OH group on the surface of the antiblocking agent and triethylaluminum. Quantify ethane gas and use the following formula: n ′ = P′V / RTW
[Wherein n ′ is the amount of surface-OH groups (mol / g), P ′ is pressure (atm), V is ethane gas generation amount (l), R is gas constant (atm · l / mol · degree K), T represents temperature (degree K) and W represents sample weight (g). ]
And 0.01 to 3.0 parts by weight of an inorganic antiblocking agent having a surface —OH group amount of 200 μmol or less per gram calculated in step 1; and 0.01 to 0.3 parts by weight of an organic fatty acid amide. A polyolefin-based resin composition for film is described.

JP 2003-253061 A (refer to paragraph number 0034 and paragraph numbers 0037 to 0050) JP-A-4-220443 (see claims, paragraph number 0007 and paragraph number 0008)

Thermoplastic resins are used in a wide range of applications such as films for packaging materials. When processing a thermoplastic resin into a film for packaging material, an antioxidant having a phosphite structure or a phosphonite structure in the molecule is used for the purpose of preventing thermal oxidation of the thermoplastic resin in melt kneading at a high temperature. An anti-blocking agent is blended to prevent the films formed and adhered to each other (blocking).
However, a thermoplastic resin, an antioxidant having a phosphite structure or a phosphonite structure in the molecule (hereinafter sometimes referred to as “phosphorus antioxidant”), and an inorganic antiblocking having a relatively high acid strength The thermoplastic resin composition such as pellets containing an agent absorbs moisture while being stored in a warehouse or the like, and as a result of hydrolysis of the antioxidant, it is melt-processed at a high temperature, for example, into a film or the like after storage. However, there was a problem that the thermoplastic resin deteriorated.

In order to solve the above problems, a thermoplastic resin composition such as a pellet containing a thermoplastic resin, a phosphorus-based antioxidant, and the above-mentioned inorganic antiblocking agent is not immediately stored in a warehouse or the like, but immediately the thermoplastic resin. However, in this method, it is necessary to produce pellets in accordance with the timing of producing the film, and there is a problem that the production efficiency deteriorates.
Further, after processing the thermoplastic resin composition into pellets, measures are taken to fill the pellets with moisture-proof packaging materials and store them, but with this method, the cost for moisture-proofing the packaging materials described above is taken. There was a problem that it was excessively bulky.
In addition, thermoplastic resin compositions such as pellets containing a thermoplastic resin, a phosphorus-based antioxidant, and an inorganic antiblocking agent having a relatively small solid acid amount are relatively hygroscopic even when stored in a warehouse or the like. As a result, the antioxidant is hardly hydrolyzed. As a result, the thermoplastic resin is stabilized even after the storage is completed, for example, when the film is melt-processed at a high temperature, and a high-quality film can be produced. However, since it is necessary to use an inorganic antiblocking agent having a relatively small amount of solid acid, there is a problem in that the selection range of the inorganic antiblocking agent is narrow.

An object of the present invention is to provide a thermoplastic resin composition having good hydrolysis resistance even when an inorganic antiblocking agent having a solid acid amount exceeding 100 μmol per g is used, and a method for producing the same.
Another object of the present invention is to improve the hydrolysis resistance of the phosphorus-based antioxidant, so that the thermoplastic resin composition does not lose its quality even if it is stored for a long time after the thermoplastic resin composition is produced. The object is to provide a resin composition.
Another object of the present invention is to provide a method for producing an inexpensive thermoplastic resin composition that does not require the moisture-proof packaging material described above.
Moreover, the subject other than the above of the present invention is that when a thermoplastic resin composition such as a pellet containing a thermoplastic resin, a phosphorus-based antioxidant and the above-mentioned inorganic antiblocking agent is immediately processed into a thermoplastic resin film. It is providing the method of producing said thermoplastic resin composition efficiently.

  As a result of intensive studies, the present inventor has completed the present invention.

  That is, the present invention (i) contains the following (A), (B), (C) and (D), and the antioxidant of (B) is 0.1 per 100 parts by weight of the resin of (A). 001 to 1 part by weight, (C) inorganic antiblocking agent is 0.001 to 5 parts by weight, and (D) neutralizing agent is 0.001 to 1 part by weight A plastic resin composition is provided.

(A) Thermoplastic resin (B) Antioxidant having at least a phosphite structure represented by the following formula (1) or a phosphonite structure represented by the following formula (2) in the molecule

［式中、Ｑは２価の炭化水素残基を表す。］
（Ｃ）固体酸量が、１ｇ当たり１００μｍｏｌを超える無機アンチブロッキング剤
（Ｄ）ヒンダードピペリジン化合物、カルボン酸アミド系化合物、ハイドロタルサイト類、金属水酸化物及びカルボン酸金属塩からなる群より選ばれる少なくとも一種の中和剤

[Wherein Q represents a divalent hydrocarbon residue. ]
(C) Inorganic anti-blocking agent whose solid acid amount exceeds 100 μmol per gram (D) Selected from the group consisting of hindered piperidine compounds, carboxylic acid amide compounds, hydrotalcites, metal hydroxides and carboxylic acid metal salts At least one neutralizing agent

Further, (ii) of the present invention comprises 100 parts by weight of the thermoplastic resin (A), 0.001 to 1 part by weight of the following antioxidant (B) and 0.001 of the inorganic antiblocking agent (C). The present invention provides a method for producing a thermoplastic resin composition, comprising blending ˜5 parts by weight and 0.001 to 1 part by weight of a neutralizing agent (D), and melt-kneading.
(A) Thermoplastic resin (B) Antioxidant having at least a phosphite structure represented by the following formula (1) or a phosphonite structure represented by the following formula (2) in the molecule

[Wherein Q represents a divalent hydrocarbon residue. ]
(C) Inorganic anti-blocking agent whose solid acid amount exceeds 100 μmol per gram (D) Selected from the group consisting of hindered piperidine compounds, carboxylic acid amide compounds, hydrotalcites, metal hydroxides and carboxylic acid metal salts At least one neutralizing agent

According to (i) of the present invention, the hydrolysis resistance of the phosphorus-based antioxidant is improved, and the quality of the thermoplastic resin composition can be maintained even if it is stored for a long time after the thermoplastic resin composition is produced. Is not impaired. Further, according to (i) of the present invention, moisture absorption is relatively small even during storage in a warehouse or the like, and the antioxidant is hardly hydrolyzed. Thereby, after completion | finish of storage, even when melt-processing a film etc. at high temperature, stabilization of a thermoplastic resin is achieved and a high quality film can be manufactured.
Moreover, according to (ii) of this invention, deterioration of the thermoplastic resin at the time of melt-kneading can be prevented. Further, according to (ii) of the present invention, the moisture-proof packaging material described above is unnecessary, and the thermoplastic resin composition can be produced at a low cost. Moreover, according to (ii) of the present invention, the thermoplastic resin composition can be efficiently produced even when the thermoplastic resin composition such as the pellet is immediately processed into a thermoplastic resin film. . Moreover, according to (ii) of the present invention, it is possible to provide a method for producing a thermoplastic resin composition having improved hydrolysis resistance even when an inorganic antiblocking agent having a solid acid amount exceeding 100 μmol per gram is used. it can.

Hereinafter, the present invention will be described in detail.
Examples of the thermoplastic resin (A) used in (i) and (ii) of the present invention include the following.
(1) Polyethylene, for example, high density polyethylene (HD-PE), low density polyethylene (LD-PE), linear low density polyethylene (LLDPE), (2) polypropylene, (3) methylpentene polymer, (4) EEA (Ethylene / ethyl acrylate copolymer) resin, (5) ethylene / vinyl acetate copolymer resin, (6) polystyrenes such as polystyrene, poly (p-methylstyrene) and poly (α-methylstyrene), (7) AS (acrylonitrile / styrene copolymer) resin, (8) ABS (acrylonitrile / butadiene / styrene copolymer) resin, (9) AAS (special acrylic rubber / acrylonitrile / styrene copolymer) resin, (10) ACS (acrylonitrile / chlorine) Polyethylene / styrene copolymer) resin,

(11) Chlorinated polyethylene, polychloroprene and chlorinated rubber, (12) polyvinyl chloride and polyvinylidene chloride, (13) methacrylic resin, (14) ethylene / vinyl alcohol copolymer resin, (15) fluororesin, (16 ) Polyacetal, (17) grafted polyphenylene ether resin and polyphenylene sulfide resin, (18) polyurethane, (19) polyamide, (20) polyester resin such as polyethylene terephthalate and polybutylene terephthalate, (21) polycarbonate, (22) poly Acrylate, (23) polysulfone, polyetheretherketone and polyethersulfone, (24) aromatic polyester resin, (25) diallyl phthalate prepolymer, (26) silicone resin, (27) 1,2-poly Butadiene, (28) polyisoprene, (29) styrene / butadiene copolymer, (30) butadiene / acrylonitrile copolymer, (31) ethylene / propylene copolymer, (32) ethylene / MMA (methyl methacrylate) copolymer Coalescence.

As the thermoplastic resin in the present invention (i) and (ii), the above-exemplified resins can be used alone or as a mixture.
In (i) and (ii) of the present invention, polyolefins such as polyethylene (for example, HD-PE, LD-PE, LLDPE) and polypropylene; copolymers such as ethylene and vinyl acetate; copolymers such as ethylene and MMA An engineering resin such as polyamide, polyethylene terephthalate, polybutylene terephthalate or polycarbonate is preferably used.

The method for producing the polyolefin is not particularly limited. For example, it may be obtained by radical polymerization, and a catalyst containing a metal of Group IVb, Group Vb, Group VIb or Group VIII of the periodic table is used. It may be produced by polymerization.
The metal-containing catalyst may be a metal complex having one or more ligands, for example, an oxide coordinated by a π bond or a σ bond, a halogen compound, an alcoholate, an ester, an aryl, These complexes may be used as they are or may be supported on a base material such as magnesium chloride, titanium chloride, alumina, or silicon oxide.
As polyolefin, what was manufactured, for example using a Ziegler Natta catalyst, a metallocene catalyst, a Philips catalyst etc., is used preferably.

Also, the engineering resin is not particularly limited.
For example, any polyamide resin may be used as long as it has an amide bond in the polymer chain and can be melted by heating. The method for producing the polyamide resin is also not limited, and for example, it may be produced by a method such as a condensation reaction of diamines and dicarboxylic acids, a condensation reaction of aminocarboxylic acids, or ring-opening polymerization of lactams.
Typical examples of the polyamide resin include nylon 66, nylon 69, nylon 610, nylon 612, poly-bis (p-aminocyclohexyl) methane dodecamide, nylon 46, nylon 6, nylon 12, nylon 66 and nylon 6 Examples thereof include a copolymer such as nylon 66/6, nylon 6/12, and the like.
Any polyester resin may be used as long as it has an ester bond in the polymer chain and can be melted by heating.
Specific examples of the polyester resin include homopolyesters and copolyesters obtained by polycondensation of dicarboxylic acids and dihydroxy compounds.
Any polycarbonate resin may be used as long as it has a carbonate bond in the polymer chain and can be melted by heating.
Examples of such polycarbonate resins include phosgene and diphenyl carbonate in the presence or absence of a small amount of a polyhydroxy compound in the presence or absence of a solvent, an acid acceptor or a molecular weight modifier. The polycarbonate obtained by making a carbonate precursor react is mentioned.
The polycarbonate resin may be linear or branched, and may be a copolymer.

  In (i) and (ii) of the present invention, as an antioxidant having at least a phosphite structure represented by the above formula (1) or a phosphonite structure represented by the above formula (2) in the molecule, for example, The compounds represented by the following formulas (I) to (IV) are preferably used.

（Ｉ）
［式中、Ｒ^１、Ｒ^２、Ｒ^４及びＲ^５は、それぞれ独立に水素原子、炭素数１〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表し、Ｒ^３は水素原子又は炭素数１〜８のアルキル基を表す。Ｘは単結合、硫黄原子又は−ＣＨＲ⁶−基を表す。Ｒ⁶は水素原子、炭素数１〜８のアルキル基又は炭素数５〜８のシクロアルキル基を表す。
Ａは炭素数２〜８のアルキレン基又は＊−ＣＯＲ⁷−基を表し、Ｒ⁷は単結合又は炭素数１〜８のアルキレン基を表し、＊は式（Ｉ）におけるフォスファイト構造の酸素原子に結合していることを表す。
Ｙ及びＺは、いずれか一方がヒドロキシル基、炭素数１〜８のアルコキシ基又は炭素数７〜１２のアラルキルオキシ基を表し、他方が水素原子又は炭素数１〜８のアルキル基を表す。
但し、Ｙがヒドロキシル基であるときは、Ｒ^４及びＲ^５の一方は炭素数３〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表す。
また、式（Ｉ）における２個のＲ^１は互いに同一でもよく、異なってもよい。さらに、式（Ｉ）における２個のＲ^２は互いに同一でもよく、異なってもよい。そして、式（Ｉ）における２個のＲ^３は互いに同一でもよく、異なってもよい。］

(I)
[Wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcyclohexane having 6 to 12 carbon atoms. An alkyl group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group is represented, and R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom or a —CHR ⁶ — group. R ⁶ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms.
A represents an alkylene group having 2 to 8 carbon atoms or * —COR ⁷ — group, R ⁷ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and * represents an oxygen atom of the phosphite structure in formula (I) Indicates that it is bound to.
One of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
However, when Y is a hydroxyl group, one of R ⁴ and R ⁵ is an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, carbon It represents an aralkyl group or a phenyl group of formula 7-12.
Moreover, two R < ¹ > in Formula (I) may mutually be same, and may differ. Furthermore, two R ² in the formula (I) may be the same or different. And two R < ³ > in Formula (I) may mutually be same, and may differ. ]

（ＩＩ）
（式中、Ｒ^８及びＲ^９は、それぞれ独立に水素原子、炭素数１〜９のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表す。）

(II)
(Wherein, ^{R 8} and ^{R 9} are each independently a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, cycloalkyl group having 5 to 8 carbon atoms, alkylcycloalkyl group having 6 to 12 carbon atoms, 7 carbon atoms Represents -12 aralkyl groups or phenyl groups.)

（ＩＩＩ）
（式中、Ｒ¹⁰は水素原子又はメチル基を表す。但し、式（ＩＩＩ）における複数のＲ¹⁰は互いに同一でもよく、異なってもよい。）

(III)
(In the formula, R ¹⁰ represents a hydrogen atom or a methyl group. However, a plurality of R ¹⁰ in formula (III) may be the same as or different from each other.)

（ＩＶ）
［式中、Ｒ¹¹及びＲ^１2は、それぞれ独立に水素原子、炭素数１〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表し、ｎは０〜２の整数を表す。
但し、式（ＩＶ）におけるｎが１〜２の整数を表し、且つ、Ｒ¹¹が炭素数１〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表すときは、式（ＩＶ）における複数のＲ¹¹は互いに同一でもよく、異なってもよい。また、式（ＩＶ）におけるｎが１〜２の整数を表し、且つ、Ｒ^1２が炭素数１〜８のアルキル基、炭素数５〜８のシクロアルキル基、炭素数６〜１２のアルキルシクロアルキル基、炭素数７〜１２のアラルキル基又はフェニル基を表すときは、式（ＩＶ）における２個のＲ^1２は互いに同一でもよく、異なってもよい。］

(IV)
[Wherein, R ¹¹ and R ¹² each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or 7 carbon atoms. -12 represents an aralkyl group or phenyl group, and n represents an integer of 0-2.
However, n in formula (IV) represents an integer of 1 to 2 and R ¹¹ is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When it represents a group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, a plurality of R ¹¹ in formula (IV) may be the same as or different from each other. N in Formula (IV) represents an integer of 1 to 2 and R ¹² is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When a group, an aralkyl group having 7 to 12 carbon atoms or a phenyl group is represented, the two R ¹² in the formula (IV) may be the same or different. ]

In (i) of the present invention, R ¹ and R ² in the compound represented by the formula (I) are an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcyclohexane having 6 to 12 carbon atoms. R ⁴ is preferably an alkyl group, and R ⁴ is an i-propyl group, i-butyl group, sec-butyl group, t-butyl group, t-pentyl group, i-octyl group, t-octyl group, cyclohexyl group, 1 - is preferably a methyl cyclohexyl group or 2-ethylhexyl group, ^{R 5} is a hydrogen atom, a methyl group, an ethyl group, n- propyl group, i- propyl, n- butyl group, i- butyl group, sec- butyl It is preferably an alkyl group having 1 to 5 carbon atoms such as a group, t-butyl group or t-pentyl group.
R ³ is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.
The divalent group X is preferably a single bond, a sulfur atom or a methylene group.
The divalent group A is a propylene group, * -CO- group or * -CO-CH ₂ CH ₂ group (-CO- marked with * indicates that it is bonded to an oxygen atom of a phosphite structure). Preferably there is.
Y is preferably a hydroxyl group, and Z is preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

In (i) of the present invention, R ⁸ and R ⁹ in the compound represented by the formula (II) are preferably a linear or branched alkyl group having 3 to 9 carbon atoms.

In (i) of the present invention, R ¹¹ in the compound represented by the formula (IV) is preferably a linear or branched alkyl group having 3 to 9 carbon atoms or an aralkyl group having 7 to 12 carbon atoms. .
R ¹² is preferably a hydrogen atom or a methyl group, and n is preferably 2.

Among the above phosphorus antioxidants, preferred compounds are exemplified below.
Tris (2,4-di-t-butylphenyl) phosphite [B-1]
6- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propoxy] -2,4,8,10-tetra-t-butyldibenz [d, f] [1,3,2] di Oxaphosphepine [B-2]
Tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene-diphosphonite [B-3]
Tetrakis (2,4-di-t-butyl-5-methylphenyl) -4,4'-biphenylene-diphosphonite [B-4]
Bis (2,4-di-t-butylphenyl) pentaerythrityl diphosphite [B-5]
Bis (2,6-di-t-butyl-4-methylphenyl) pentaerythrityl diphosphite [B-6]

In producing (i) of the present invention, 0.001 to 1 part by weight of at least one phosphorous antioxidant is contained per 100 parts by weight of the thermoplastic resin. The content of the phosphorus-based antioxidant is more preferably 0.01 to 0.5 parts by weight, and particularly preferably 0.05 to 0.2 parts by weight.
A composition having a phosphorus antioxidant content of less than 0.001 part by weight per 100 parts by weight of the thermoplastic resin cannot provide sufficient antioxidant performance during melt-kneading. On the other hand, even if it exceeds 1 part by weight of the phosphorus-based antioxidant per 100 parts by weight of the thermoplastic resin, the antioxidant performance does not change, which is economically disadvantageous.
In (ii) of the present invention, the method of mixing the phosphorus antioxidant is not particularly limited, but a method of directly mixing the phosphorus antioxidant and the thermoplastic resin, a high concentration of the phosphorus antioxidant in advance. A method of mixing the blended master batch with the thermoplastic resin, a method of kneading and mixing the heated and melted phosphorus antioxidant directly into the thermoplastic resin through the side feeder of an extruder, and the like are preferable.

The inorganic antiblocking agent in (i) and (ii) of the present invention is not particularly limited as long as the solid acid amount exceeds 100 μmol per gram, but if it exceeds 200 μm, the hydrolysis resistance improving effect Is big. Moreover, the inorganic antiblocking agent whose average particle diameter is the range of 0.1-30 micrometers is preferable.
Examples of inorganic antiblocking agents include silica, clay, diatomaceous earth, feldspar, talc, zeolite, kaolinite, wollastonite, sericite, aluminosilicate, calcium silicate, sodium aluminosilicate, sodium calcium aluminosilicate, and the like.

The amount of the solid acid of the inorganic antiblocking agent is, for example, in accordance with the method described in “Studies on pigment dispersion medium resins” (Toshikatsu Kobayashi, etc.) in “Coloring Materials, 61 [12] 692-698 (1988)”. Use the calculated value.
Specifically, 2 g of the above-mentioned inorganic antiblocking agent was placed in a centrifugal sedimentation tube, 30 ml of 0.01 N diethanolamine methylisobutylketone solution was added and ultrasonic dispersion was performed for 1 hour, and the resulting solution was centrifuged at 13000 rpm for 30 minutes. 10 ml of the obtained supernatant was collected, and the collected supernatant was diluted with 100 ml of methyl isobutyl ketone, and back-titration was performed with a methyl isobutyl ketone solution of 0.01 N perchloric acid to obtain the inorganic antiblocking agent. The solid acid amount (μmol) per gram is calculated.
The inorganic antiblocking agent used in (i) and (ii) of the present invention has a solid acid amount per gram exceeding 100 μmol.

The amount of the inorganic antiblocking agent used in (i) and (ii) of the present invention is in the range of 0.01 to 5 parts by weight and in the range of 0.05 to 2 parts by weight per 100 parts by weight of the thermoplastic resin. It is preferable.
When the amount of the inorganic antiblocking agent used is less than 0.01 parts by weight per 100 parts by weight of the thermoplastic resin, the antiblocking effect when the thermoplastic resin composition is formed into a film is not sufficient. On the other hand, even when the amount of the inorganic antiblocking agent used exceeds 5 parts by weight per 100 parts by weight of the thermoplastic resin, no improvement in the antiblocking effect commensurate with the amount used is observed.
In (i) of the present invention, the method of mixing the inorganic anti-blocking agent is not particularly limited, but a method of mixing the anti-blocking agent with a thermoplastic resin as it is or a master batch in which the inorganic anti-blocking agent is blended at a high concentration in advance. A method of mixing with a thermoplastic resin is preferred.
The neutralizing agent in (i) of the present invention may be one or more selected from the group consisting of hindered amine compounds, hydrotalcites, metal hydroxides and carboxylic acid amides.
Preferred neutralizing agents include synthetic hydrotalcite, natural hydrotalcite, calcium hydroxide (hereinafter abbreviated as D-1); erucic acid amide (hereinafter abbreviated as D-2), stearic acid amide, olein Acid amide, behenic acid amide, N-stearyl butyric acid amide, N-stearyl lauric acid amide, N-stearyl stearic acid amide, N-stearyl behenic acid amide, N-oleyl oleic acid amide, N-oleyl behenic acid amide, N -Butyl erucic acid amide, N-octyl erucic acid amide, N-lauryl erucic acid amide, ethylene bis stearic acid amide, ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N'-dioleyl adipic acid amide and N , N′-dioleoyl sebacic acid amide; bis (2,2, , 6-tetramethyl-4-piperidyl) sebacate, dimethyl oxalate 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate (hereinafter referred to as D-3) Abbreviated) and poly [{6- (1,1,3,3, -tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetra Methyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] and the like.

In producing the thermoplastic resin composition of the present invention (i), 0.001 to 1 part by weight of at least one neutralizing agent described above is contained per 100 parts by weight of the thermoplastic resin.
The content of the neutralizing agent is preferably in the range of 0.01 to 0.5 parts by weight, more preferably in the range of 0.05 to 0.2 parts by weight per 100 parts by weight of the thermoplastic resin. .
A composition having a neutralizer content of less than 0.001 part by weight per 100 parts by weight of the thermoplastic resin cannot provide sufficient antioxidant performance during melt-kneading. On the other hand, even if the content of the neutralizing agent exceeds 1 part by weight per 100 parts by weight of the thermoplastic resin, the antioxidant performance of the thermoplastic resin does not change, which is economically disadvantageous.
In the present invention (ii), the method for mixing the neutralizing agent is not particularly limited. For example, a method of directly mixing a neutralizing agent and a thermoplastic resin, a method of mixing a master batch in which a neutralizing agent is mixed at a high concentration in advance with a thermoplastic resin, or a kneading and mixing of a neutralizing agent directly to a thermoplastic resin through a side feeder. And the like.
Moreover, in this invention (ii), the order which mix | blends phosphorus antioxidant, an inorganic antiblocking agent, and a neutralizing agent with resin is not specifically limited. For example, phosphorous antioxidant, inorganic antiblocking agent and neutralizing agent are combined into resin; inorganic antiblocking agent and neutralizing agent are premixed in thermoplastic resin and then phosphorus antioxidant is blended And the like. A method of blending an inorganic antiblocking agent and a neutralizing agent in advance with a resin and then blending a phosphorus-based antioxidant is preferred.

In (i) and (ii) of the present invention, in addition to the thermoplastic resin, phosphorus antioxidant and inorganic antiblocking agent, at least one antioxidant other than the phosphorus antioxidant, light stabilizer Further, a lubricant, an antistatic agent, an antifogging agent and the like can be blended.
Examples of antioxidants, light stabilizers, lubricants, antistatic agents and pigments other than the above-described phosphorus antioxidants that can be used in (i) and (ii) of the present invention include the following.
<Antioxidants other than the above phosphorus antioxidants>
2,6-di-tert-butyl-4-methylphenol, n-octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, pentaerythrityl tetrakis (3- (3,5- Di-t-butyl-4-hydroxyphenyl) propionate), triethylene glycol bis (3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate), 1,3,5-trimethyl-2, 4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 3,9-bis (2- (3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy) -1,1-dimethylethyl) -2,4,8,10-tetra Oxaspiro [5 · 5] undecane, 2,2′-methylenebis (6-tert-butyl-4-methylphenol), 4,4′-butylidenebis (6-tert-butyl-3-methylphenol), 4,4 ′ -Thiobis (6-t-butyl-3-methylphenol), 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2- (1 -(2-hydroxy-3,5-t-amylphenyl) ethyl) -4,6-di-t-amylphenyl acrylate, dialkyl (C12-18) 3,3'-thiodipropionate, pentaerythrityl tetrakis (3-lauryl thiopropionate) and the like.
<Light stabilizer>
2-hydroxy-4-n-octoxybenzophenone, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzo Triazole, 2,4-di-t-butylphenyl 3,5-di-t-butyl-4-hydroxybenzoate and the like.
<Lubricant>
Paraffin, polyethylene wax, stearic acid, butyl stearate, hydrogenated castor oil, stearyl alcohol, calcium stearate, etc.
<Antistatic agent>
Cationic antistatic agents such as primary amine salts, tertiary amine salts, quaternary amine salts and pyridine derivatives; sulfated oils, soaps, sulfated ester oils, sulfated amide oils, sulfated ester salts of olefins Anionic antistatic agents such as fatty alcohol sulfates, alkyl sulfates, fatty acid ethyl sulfonates, alkyl naphthalene sulfonates, alkyl benzene sulfonates, oxalate sulfonates and phosphate ester salts; Partial fatty acid ester of alcohol, ethylene oxide adduct of fatty alcohol, ethylene oxide adduct of fatty acid, ethylene oxide adduct of fatty amino or fatty acid amide, ethylene oxide adduct of alkylphenol, ethylene of partial fatty acid ester of polyhydric alcohol Oxide adducts and polymers Nonionic antistatic agents such as ethylene glycol; carboxylic acid derivatives and amphoteric antistatic agents such as imidazoline derivatives <antifogging agent>
Stearic acid monoglyceride, oleic acid monoglyceride, polyglycerin oleate, sorbitan monolaurate, sorbitan monostearate, etc.

In the production method of the present invention (ii), examples of the apparatus used for producing the thermoplastic resin composition include a mixer such as a tumbler blender, a Henschel mixer or a super mixer; a single-screw or multi-screw extruder; a kneader or a banbury. A mixer etc. are mentioned.
The thermoplastic resin composition comprises a thermoplastic resin, a phosphorus-based antioxidant, an inorganic antiblocking agent having a solid acid amount exceeding 100 μmol per gram, and an oxidation other than the above-described phosphorus-based antioxidant used as necessary. Inhibitors, light stabilizers, lubricants, antistatic agents, pigments, etc. are mixed uniformly in advance using a mixer such as a tumbler blender, Henschel mixer or super mixer, and then melted using a single screw extruder or multi-screw extruder. A method of kneading and granulating; a method of granulating using an extruder after melt-kneading with a kneader, a Banbury mixer or the like.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further in detail, this invention is not limited by these examples.

[Inorganic anti-blocking agent used in each example]
C-3: “Insulite MC-6” (aluminosilicate) manufactured by Mizusawa Chemical Co., Ltd.
C-4: “Dikalite WF” (diatomaceous earth) manufactured by Grefco Co., Ltd.
C-5: “Mizukasil P-707” (synthetic silica) manufactured by Mizusawa Chemical Co., Ltd.

[Preparation of Resin Composition of Example 1]
To 100 parts by weight of unstabilized polyethylene powder, 0.1 part by weight of C-5 and dimethyl oxalate 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine 0.1 parts by weight of the polycondensate was blended with a lab plast mill. Thereafter, 0.2 part by weight of the above B-1 was added, and the thermoplastic resin composition was kneaded to obtain a uniform resin composition. The resin composition was finely cut to obtain pellets.

[Measurement example 1 of solid acid amount of inorganic antiblocking agent]
1 g of the above C-5 was placed in a centrifugal sedimentation tube, 50 ml of a 0.02N diethanolamine methyl isobutyl ketone solution was added, and ultrasonic dispersion was performed for 1 hour. The liquid obtained after ultrasonic dispersion was centrifuged at 13000 rpm for 30 minutes, and 10 ml of the obtained supernatant was collected. The collected supernatant was diluted with 100 ml of methyl isobutyl ketone. This diluted solution was subjected to back titration with a methyl isobutyl ketone solution of 0.01N perchloric acid, and the amount of solid acid (μmol) per 1 g of Sample C-5 was calculated.

[Measurement example 2 of solid acid amount of inorganic antiblocking agent]
2 g of the above C-3 was placed in a centrifugal sedimentation tube, and 30 ml of a 0.01 N diethanolamine methyl isobutyl ketone solution was added, followed by ultrasonic dispersion for 1 hour. The liquid obtained after ultrasonic dispersion was centrifuged at 13000 rpm for 30 minutes, and 10 ml of the obtained supernatant was collected.
The collected supernatant was diluted with 100 ml of methyl isobutyl ketone. This diluted solution was subjected to back titration with a methyl isobutyl ketone solution of 0.01N perchloric acid, and the amount of solid acid (μmol) per 1 g of Sample C-3 was calculated.

[Storage stability test]
The pellets obtained in the preparation examples of the thermoplastic resin composition were stored at 50 ° C. and 80% relative humidity. After storage, the liquid containing phosphorus antioxidant obtained by Soxhlet extraction was analyzed by gas chromatography or liquid chromatography to determine the content of antioxidant in the pellets. The content after completion of storage when the content of phosphorus-based antioxidant in the pellet at the start of storage was taken as 100 was expressed as a residual rate (%).

Examples 1-4, Comparative Example 1, and Reference Examples 1-3
In Examples 2 to 4 and Comparative Examples 1 to 4, pellets were produced according to the preparation of the resin composition of Example 1. Moreover, the solid acid amount in the inorganic antiblocking agent used in Examples 1-4 and Comparative Example 1 was measured according to the measurement example 1 of the solid acid amount. The amount of solid acid per gram of the inorganic antiblocking agent used in Comparative Examples 2 to 3 was measured according to Measurement Example 2 for the amount of solid acid.

* 1. Number of parts added per 100 parts by weight of thermoplastic resin (weight)

The thermoplastic resin obtained by this invention is used for uses, such as a film for packaging materials, for example.

Claims (10)

The following (A), (B), (C) and (D) are contained, and the antioxidant of (B) is 0.001 to 1 part by weight per 100 parts by weight of the resin of (A), ( A thermoplastic resin composition, wherein the inorganic antiblocking agent (C) is 0.001 to 5 parts by weight, and the neutralizing agent (D) is 0.001 to 1 parts by weight.
(A) Thermoplastic resin (B) Antioxidant having at least a phosphite structure represented by the following formula (1) or a phosphonite structure represented by the following formula (2) in the molecule

[Wherein Q represents a divalent hydrocarbon residue. ]
(C) Inorganic anti-blocking agent whose solid acid amount exceeds 100 μmol per gram (D) Selected from the group consisting of hindered piperidine compounds, carboxylic acid amide compounds, hydrotalcites, metal hydroxides and carboxylic acid metal salts At least one neutralizing agent The antioxidant having at least a phosphite structure represented by the formula (1) in the molecule is a compound having the phosphite structure and a hindered phenol structure represented by the following formula (3) in the same molecule. Item 2. The thermoplastic resin composition according to Item 1.

[Wherein, A represents an alkylene group having 2 to 8 carbon atoms or **-COR ⁷ -group (R ⁷ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and ** is represented by formula (1). It shows bonding to any one of three oxygen atoms in the phosphite structure.
R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or an aralkyl having 7 to 12 carbon atoms. Represents a group or a phenyl group.
One of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
However, when Y is a hydroxyl group, one of R ⁴ and R ⁵ is an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, carbon It represents an aralkyl group or a phenyl group of formula 7-12. ] 3. The heat according to claim 2, wherein the compound having a phosphite structure represented by the formula (1) and a hindered phenol structure represented by the formula (3) in the same molecule is a compound represented by the following formula (I). Plastic resin composition.

(I)
[Wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcyclohexane having 6 to 12 carbon atoms. An alkyl group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group is represented, and R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom or a —CHR ⁶ — group. R ⁶ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms.
A is an alkylene group or a * -COR ⁷ 2 to 8 carbon atoms - group. R ⁷ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and —CO— marked with * represents that it is bonded to an oxygen atom of the phosphite structure in formula (I).
One of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
However, when Y is a hydroxyl group, one of R ⁴ and R ⁵ is an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, carbon It represents an aralkyl group or a phenyl group of formula 7-12.
Moreover, two R < ¹ > in Formula (I) may mutually be same, and may differ. Furthermore, two R ² in the formula (I) may be the same or different. And two R < ³ > in Formula (I) may mutually be same, and may differ. ] The thermoplastic resin composition according to claim 1, wherein the antioxidant having a phosphite structure represented by the formula (1) in the molecule is a compound represented by the following formula (II) or (IV).

(II)
[Wherein R ⁸ and R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or 7 carbon atoms. Represents -12 aralkyl groups or phenyl groups. ]

(IV)
[Wherein, R ¹¹ and R ¹² each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or 7 carbon atoms. -12 represents an aralkyl group or phenyl group, and n represents an integer of 0-2.
However, n in formula (IV) represents an integer of 1 to 2 and R ¹¹ is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When it represents a group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, a plurality of R ¹¹ may be the same or different. In formula (IV), n represents an integer of 1 to 2, and R ¹² is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When it represents a group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, a plurality of R ¹² may be the same or different. ] The thermoplastic resin composition according to claim 1, wherein the antioxidant having a phosphonite structure represented by the formula (2) in the molecule is a compound represented by the following formula (III).

(III)
[Wherein, R ¹⁰ represents a hydrogen atom or a methyl group. However, several R < ¹⁰ > in Formula (III) may mutually be same, and may differ. ] 100 parts by weight of the thermoplastic resin (A), 0.001 to 1 part by weight of the following antioxidant (B), 0.001 to 5 parts by weight of the inorganic antiblocking agent (C) and a neutralizing agent (D ) In an amount of 0.001 to 1 part by weight, and melt-kneading.
(A) Thermoplastic resin (B) Antioxidant having at least a phosphite structure represented by the following formula (1) or a phosphonite structure represented by the following formula (2) in the molecule

[Wherein Q represents a divalent hydrocarbon residue. ]
(C) Inorganic antiblocking agent whose solid acid amount is 100 μmol or less per gram (D) Selected from the group consisting of hindered piperidine compounds, carboxylic acid amide compounds, hydrotalcites, metal hydroxides and carboxylic acid metal salts At least one neutralizing agent The antioxidant having at least a phosphite structure represented by the formula (1) in the molecule is a compound having the phosphite structure and the hindered phenol structure represented by the following formula (3) in the same molecule. Item 7. A method for producing a thermoplastic resin composition according to Item 6.

[In the formula, A represents an alkylene group having 2 to 8 carbon atoms or **-COR ⁷ — group (R ⁷ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and ** is represented by formula (1). It shows bonding to any one of three oxygen atoms in the phosphite structure.
R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or an aralkyl having 7 to 12 carbon atoms. Represents a group or a phenyl group.
One of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
However, when Y is a hydroxyl group, one of R ⁴ and R ⁵ is an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, carbon It represents an aralkyl group or a phenyl group of formula 7-12. ] 8. The heat according to claim 7, wherein the compound having a phosphite structure represented by the formula (1) and a hindered phenol structure represented by the formula (3) in the same molecule is a compound represented by the following formula (I). A method for producing a plastic resin composition.

(I)
[Wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcyclohexane having 6 to 12 carbon atoms. An alkyl group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group is represented, and R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom or a —CHR ⁶ — group. R ⁶ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms.
A is an alkylene group or a * -COR ⁷ 2 to 8 carbon atoms - group. R ⁷ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and —CO— marked with * represents that it is bonded to an oxygen atom of the phosphite structure in formula (I).
One of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
However, when Y is a hydroxyl group, one of R ⁴ and R ⁵ is an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, carbon It represents an aralkyl group or a phenyl group of formula 7-12.
Moreover, two R < ¹ > in Formula (I) may mutually be same, and may differ. Furthermore, two R ² in the formula (I) may be the same or different. And two R < ³ > in Formula (I) may mutually be same, and may differ. ] The method for producing a thermoplastic resin composition according to claim 6, wherein the antioxidant having a phosphite structure represented by the formula (1) in the molecule is a compound represented by the following formula (II) or (IV).

(II)
[Wherein R ⁸ and R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or 7 carbon atoms. Represents -12 aralkyl groups or phenyl groups. ]

(IV)
[Wherein, R ¹¹ and R ¹² each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, or 7 carbon atoms. -12 represents an aralkyl group or phenyl group, and n represents an integer of 0-2.
However, n in formula (IV) represents an integer of 1 to 2 and R ¹¹ is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When it represents a group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, a plurality of R ¹¹ may be the same as or different from each other. In formula (IV), n represents an integer of 1 to 2, and R ¹² is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl having 6 to 12 carbon atoms. When it represents a group, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group, a plurality of R ¹² may be the same or different. ] The method for producing a thermoplastic resin composition according to claim 6, wherein the antioxidant having a phosphonite structure represented by the formula (2) in the molecule is a compound represented by the following formula (III).

(III)
[Wherein, R ¹⁰ represents a hydrogen atom or a methyl group. However, several R < ¹⁰ > in Formula (III) may mutually be same, and may differ. ]