JPH0853571A - Thermoplastic resin composition, production thereof, and electromagnetic-shielding molded products therefrom - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition in which a cleavable layer compound disperses in a thermoplastic resin in a finely cleaved state, thus is useful as a material for machine parts and for packaging and the like because of its excellent conductivity and electromagnetic wave absorption. CONSTITUTION:This composition comprises (A) a thermoplastic resin, for example, polypropylene resin or polyamide resin and (B) a conductive and electromagnetic wave-absorbing laminar compound (preferably laminar transition metal oxygen acid salt, graphite) wherein the amount of component B is 0.01-40wt.% calculated as ash, the average thickness is 0.1-500nm and more than 5wt.% of component B have 0.1-50nm thickness. It is preferred that the laminar compound includes an organic compound or molecular compound between these molecular layers and more than 40% of the laminar compound is dispersed in 0.1-10nm thickness. This composition is obtained in a powdery composite form by loading stress and compression force of higher than 500sec<-1> shear rate to a powdery mixture of components A and B simultaneously at a temperature lower than the softening point of component A.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition and its use. More specifically, the present invention relates to a thermoplastic resin composition in which a cleavable layered compound is dispersed in an unprecedented fine cleavage state, and has electrical conductivity or electromagnetic wave absorption, a method for producing the same, and an application thereof.

[0002]

2. Description of the Related Art Conventionally, a filler has been widely added to a molding resin material for the purpose of modifying its physical properties. For example, layered compounds such as talc, mica and glass flakes are added for the purpose of strengthening the finally obtained product and improving the slipperiness of the product film. However, such conventional techniques have drawbacks such as an increase in the specific gravity of the product, a decrease in the surface smoothness of the molded product, and a decrease in the toughness of the molded product. As a remedy for these drawbacks, the aspect ratio of the filler is improved, or fine dispersion,
That is, it is considered that the layered compound can be improved by making it thinner.

As an attempt to reduce the thickness of such a layered compound, a method of adding and dispersing organic bentonite at an arbitrary stage in the production of a polyamide molded article is disclosed in JP-A-48-103653 and JP-A-51-109998. JP 62
JP-A-74957 discloses a composition comprising a polyamide and a cation-exchange layered silicate ionically bonded to the polyamide, and a method for producing the composition. Although the dispersibility in nylon 6 resin can be greatly improved by the methods disclosed in these publications, since the layered compound is a technique limited to cation-exchange layered silicate, The product did not exhibit electromagnetic wave shielding properties.

Further, Japanese Patent Laid-Open No. 5-306370 discloses a composition in which a layered phosphate is dispersed in a polyamide resin at a unit layer level, but it is still insufficient in terms of electromagnetic wave shielding property. It was a thing. On the other hand, a technology for dispersing layered transition metal oxyacid salts, such as layered titanate, layered titanoniobate, and layered niobate, which have the property of absorbing light in the visible to ultraviolet region, into a thermoplastic resin on the nanometer order. , Or a fine dispersion technique of a layered compound having conductivity such as graphite, but having substantially no charge and making it difficult to intercalate an organic compound, has not been heretofore known.

[0005]

SUMMARY OF THE INVENTION In view of the present state of the art of dispersing a layered compound in a thermoplastic resin matrix as described above, an object of the present invention is to disperse the cleavable layered compound in a finely cleaved state which has never been seen before. The present invention provides a thermoplastic resin composition that exhibits electrical conductivity or electromagnetic wave absorption, a method for producing the same, and an application thereof.

[0006]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above-mentioned problems, and as a result, by using a specific fine dispersion technique, a layered compound is dispersed in a finely cleaved state which has never been seen before. Then, it was found that a novel thermoplastic resin composition having an excellent electromagnetic wave shielding property was obtained, and the present invention was completed. In order to solve the above-mentioned problems, the present invention provides a thermoplastic resin composition comprising a thermoplastic resin and a layered compound, wherein the layered compound has conductivity or electromagnetic wave absorption. And having an ash content of 0.01 to 40% by weight,
The average thickness is in the range of 0.1 to 500 nm, and 5% by weight or more of the layered compound has a thickness of 0.1 to 50.
This means that it is dispersed in the range of nm. Further, in the invention according to claim 4, in the powder mixture of the thermoplastic resin powder and the layered compound powder, the shear rate is 500 sec ^-1 or more under a temperature condition lower than the softening temperature of the thermoplastic resin. The means for simultaneously applying the shearing force and the compressive force to form a powder composite, or melt-mixing the powder composite with a thermoplastic resin is taken. Further, the invention according to claim 5 is to take a means to obtain an electromagnetic wave shielding molded product comprising the thermoplastic resin composition according to claim 1.

Hereinafter, the present invention will be described in detail. The thermoplastic resin composition according to the present invention contains two components (a) a thermoplastic resin and (b) a layered compound as essential components. In the present invention, the thermoplastic resin as the component (a) functions as a matrix for finely dispersing the layered compound as the component (b). The type of the thermoplastic resin is not particularly limited, but the layered compound of the component (b) is finely dispersed, and a preferable effect is particularly expected.The component (a) is a polypropylene resin, a polyamide resin, an aromatic polycarbonate. Examples thereof include resins, aromatic polyester resins, polyacetal resins, polyphenylene ether resins, polyarylene sulfide resins, acrylic resins and styrene resins.

[0008] The polypropylene resin is a polymer obtained by addition polymerization of propylene in the presence of a transition metal catalyst. Such a polymer has a structure in which a methyl group is bonded to every other carbon atom of the methylene chain, and the carbon element to which the methyl group is bonded is an asymmetric center. Therefore, due to the stereoregularity of the chain, syndiotactic , Isotactic, atactic, etc. can be classified. Any of these stereoregular structures may be used, and a plurality of types may be used in combination. Further, the polypropylene resin may have a branched structure. The production method of the polypropylene resin is not particularly limited. The molecular weight of these polypropylene resins is not particularly limited, and those having a melt index in the normal range of 0.1 to 50 are preferably used, and those having a melt index in the range of 0.5 to 30 are particularly preferable.

The polyamide resin is a polymer containing an amide bond (-NHCO-) in the main chain and capable of being heated and melted. Specific examples of the polyamide-based resin that can be used include polytetramethylene adipamide (nylon 46), polycaprolactam (nylon 6), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610). Polyhexamethylene dodecamide (nylon 612), polyundecanolactam (nylon 11), polydodecanolactam (nylon 12) Polyamide obtained from terephthalic acid and / or isophthalic acid and hexamethylenediamine, adipic acid and metaxylyl Polyamide obtained from diamine, terephthalic acid and / or isophthalic acid, polyamide obtained from adipic acid and hexamethylenediamine, terephthalic acid and / or isophthalic acid, adipic acid and metaxylenediamine The obtained polyamide, a copolymerized polyamide containing 1,3-phenylenedioxydiacetic acid as a copolymerization component, a copolymerized polyamide containing a dimerized fatty acid as a copolymerization component, and the like may be used. ) Aromatic polyamide resins may be used.
The polyamide resin may be a single kind or a mixture of two or more kinds.

Among these, nylon 6 and nylon 66
Is preferable because it is excellent in balance between toughness and rigidity. Further, a polyamide obtained from terephthalic acid and / or isophthalic acid and hexamethylenediamine, a polyamide obtained from adipic acid and metaxylylenediamine, a polyamide obtained from terephthalic acid, adipic acid and hexamethylenediamine, and copolymerization Copolyamides containing 1,3-phenylenedioxydiacetic acid as a component are suitable because of their excellent gas barrier properties. The molecular weight of the polyamide-based resin is not particularly limited, but normally, one having a relative viscosity measured in concentrated sulfuric acid of 25 ° C. in the range of 0.5 to 5.0 is preferably used, and from the viewpoint of toughness and moldability. More preferred is 0.
It is in the range of 8 to 4.0.

The aromatic polycarbonate resin is one or more kinds of bisphenols which may contain polyhydric phenols as a copolymerization component, bisalkyl carbonate,
It is a polymer produced by the reaction with carbonic acid esters such as bisaryl carbonate and phosgene. The method for producing the aromatic polycarbonate resin used in the present invention is not limited. For example, (1) an interfacial polymerization method in which an alkali metal salt of a bisphenol and a carbonic acid ester derivative active in a nucleophilic attack are used as raw materials, and a polycondensation reaction is carried out at an interface between an organic solvent that dissolves the produced polymer and alkaline water, ( 2) Pyridine method in which polycondensation reaction is carried out in an organic base such as pyridine using bisphenols and a carbonate derivative active in nucleophilic attack as raw materials, (3) Carbonic esters such as bisphenol carbonate and bisaryl carbonate It may be produced by any conventionally known method such as a melt polymerization method in which the raw materials are and are subjected to melt polycondensation. The aromatic polycarbonate resins may be used alone or in combination of two or more.

The molecular weight of the aromatic polycarbonate resin used in the present invention is not particularly limited, and is usually measured by gel permeation chromatography (GPC) with a tetrahydrofuran (THF) solvent at 40 ° C.
The weight average molecular weight Mw may be 15,000 or more with the monomolecular weight dispersed polystyrene as a control. Considering toughness and moldability, it is preferable to select in the range of 20,000 to 80,000, and most preferable to be 35,000.
It is in the range of 65,000.

The aromatic polyester resin is a polyester having an aromatic ring in its molecular chain, which is obtained by a condensation reaction of a dicarboxylic acid or its ester-forming derivative with a diol or its ester-forming derivative.
Specific examples of the aromatic polyester resin include polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, polyhexamethylene terephthalate, polycyclohexane dimethylene terephthalate and other polyalkylene terephthalates, poly (ethylene terephthalate / ethylene isophthalate) copolymers, Polyalkylene phthalate such as poly (butylene terephthalate / butylene isophthalate) copolymer, polyalkylene naphthalate such as polyethylene naphthalate, polybutylene naphthalate, aliphatic such as poly (butylene terephthalate / butylene dodecadioate) copolymer Examples thereof include polyalkylene terephthalate containing dicarboxylic acid. These may be used alone or in combination of two or more.

Of these, polyalkylene terephthalates such as polyethylene terephthalate, polybutylene terephthalate and polycyclohexane dimethylene terephthalate, and polyalkylene naphthalates such as polyethylene naphthalate and polybutylene naphthalate are preferably used in the present invention. Most preferred are polyethylene terephthalate and polybutylene terephthalate. There is no particular limitation on the molecular weight of the aromatic polyester used in the present invention, and it is preferable to use a mixed solvent of phenol and tetrachloroethane in a weight ratio of 1: 1 at a concentration of 1 g / dl and an intrinsic viscosity measured at 30 ° C. [Η] is
It is in the range of 0.5 to 3.0 dl / g. If the intrinsic viscosity is smaller than this range, the toughness is extremely lowered, and if it is larger than this range, the melt viscosity is too large and molding is hindered, which is not preferable.

The polyacetal resin is represented by the following formula:-(-O-CHR-) _n- , [wherein R is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and n is a natural number. Is. ] It is a polymer which has the repeating unit of the oxyalkylene structure shown by these as a main. There is no limitation on the production method, and polyoxymethylene is mentioned as a typical structure, and it is usually produced by ring-opening polymerization of trioxane. Further, a polyacetal copolymer in which most of the main chain is composed of an oxymethylene chain can also be used, and those crosslinked or graft-modified by a known method can also be used as long as they have thermoplasticity, and plural kinds of polyacetals can be used. Can also be used together. The molecular weight of the polyacetal resin used in the present invention is not particularly limited, and the melt index can be selected within the range of 1 to 25, and more preferably 5 to 25.

The polyphenylene ether resin is a polymer in which benzene ring residues are linked via an ether bond and can be melted by heating. These are polymers produced from a phenol or a reactive derivative thereof as a raw material by a known method, for example, oxygen using an oxidative coupling catalyst, or oxidative coupling polymerization with an oxygen-containing gas. Specific examples of the phenols and the polymerization catalyst are described in detail, for example, in JP-A No. 4-239029, and typical phenols include phenol and o-
Examples thereof include cresol, 2,6-xylenol, 2,5-xylenol, methylphenols such as 2,3,6-trimethylphenol and the like, and these phenols may be used alone or in combination of two or more kinds. The most common polyphenylene ether resin is poly (2,6-dimethyl-1,4-phenylene) ether,
Alternatively, a copolymer having this as a main structure can be used. The polyphenylene ether resin may be used alone or in combination of two or more kinds. The molecular weight of the polyphenylene ether resin used in the present invention is not particularly limited, and is usually 0.6 g /
The intrinsic viscosity [η] of a dl concentration chloroform solution at 25 ° C. is selected in the range of 0.2 to 0.6 dl / g, and in the range of 0.35 to 0.55 dl / g from the viewpoint of toughness and moldability. It is preferable to select.

Polyarylene sulfide resin is a
A polymer in which aromatic groups are linked via thioether bonds.
Yes, it can be melted by heating. Of these polymer structures
Specific examples and manufacturing methods are described in, for example, JP-A-5-194851.
See the publication for details. Preferably used in the present invention
The main chain structure is represented by the following formula:-(-S-Φ-9) _n 
-, [In the formula, Φ is a phenylene group, and n is a repetition of each structure.
It is a natural number that means shi. ] With a repeating unit of
Liphenylene sulfide and the following formula, namely,-(-S
−Φ−)_m -(-SO₂ −Φ−)_n -, [Where Φ is
The phenylene group, m and n are self-identifying the repeating of each structure.
It is a natural number, and each repeating unit represented by m and n is a random
Either an array of cells or an array of blocks
Is also good. ] Polyphenylene sulph with repeating units
It is a kid-sulphone. These can be used alone or in combination of multiple types.
May be for

The molecular weight of the polyarylene sulfide resin used in the present invention is not particularly limited, and it can be usually selected in the range of 10,000 to 500,000 in terms of weight average molecular weight. From the viewpoint of toughness and formability, the range of 30,000 to 300,000 is preferable. This weight average molecular weight can be determined by gel permeation chromatography (GPC). For example, in the case of polyphenylene sulfide, 1-chloronaphthalene can be used as a developing solvent.

The acrylic resin means acrylic acid or its ester, methacrylic acid or its ester, acrylamide, methacrylamide, acrylonitrile,
It is a homopolymer or copolymer of an acrylic acid derivative such as methacrylonitrile. Such acrylic acid derivatives are described in, for example, Volume 16 of "Plastic Materials Course" published by Nikkan Kogyo Shimbun. As typical examples, methyl acrylate, ethyl acrylate, butyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, phenyl methacrylate, acrylamide, methacrylamide, acrylonitrile, Methacrylonitrile and the like can be mentioned. There is no particular limitation on the production method of the acrylic resin, conventionally known bulk polymerization,
It can be produced by radical polymerization by any polymerization method such as suspension polymerization and emulsion polymerization. A typical acrylic resin is polymethylmethacrylate (PMMA) resin, which may be used alone or in combination of two or more kinds. The molecular weight of the acrylic resin used in the present invention is not particularly limited, and the melt index is usually selected in the range of 1 to 20, and particularly preferably in the range of 5 to 15.

The styrene-based resin means a homopolymer of a styrene derivative and a copolymer resin containing a styrene derivative as a main component and a vinyl compound copolymerizable therewith. Styrene derivatives include styrene, α-methylstyrene,
Aromatic vinyl compounds such as p-chlorostyrene, p-methylstyrene and vinylnaphthalene can be mentioned. A rubber component may be allowed to coexist when the aromatic vinyl compound is polymerized. The method for producing the styrene resin is not particularly limited, and the styrene resin can be produced by radical polymerization by any conventionally known polymerization method such as bulk polymerization, suspension polymerization, bulk-suspension polymerization, or emulsion polymerization.
Typical styrene resins include general-purpose polystyrene (PS resin), rubber-reinforced polystyrene (HIPS), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS).
Resin), acrylonitri-acrylic rubber-styrene copolymer (AAS resin), acrylonitri-EPDM-styrene copolymer (AES resin), and the like, and these may be used alone or in combination of two or more. The molecular weight of the styrene resin used in the present invention is not particularly limited, and the melt index is usually selected in the range of 0.5 to 25, and particularly preferably in the range of 5 to 20.

The thermoplastic resin as the component (a) is a granular material such as beads, crumbs, powders, etc., and preferably has an average particle diameter in the range of 0.5 to 1,000 μm. Above all, 0.
5 to 500 μm, more preferably 0.5 to 10 μm
The range is 0 μm, and the most preferable range is 0.5 to 10 μm. The thermoplastic resin as the component (a) may be used alone or in combination of two or more kinds. Further, the component (a) is not limited to those exemplified above, and other thermoplastic resins not exemplified can be used together unless the gist of the present invention is impaired.

In the present invention, the layered compound as the component (b) is dispersed in the matrix of the above-mentioned component (a) and has the function of imparting conductivity or electromagnetic wave absorption to the thermoplastic resin composition of the present invention. Each effect when imparting conductivity or electromagnetic wave absorption to the thermoplastic resin composition,
The higher the degree of fine dispersion of the cleavable layered compound dispersed in the matrix, the better.

The layered compound as the component (b) may be any cleavable layered compound having conductivity or electromagnetic wave absorption, and the kind thereof is not limited. Here, “cleavability” means that a layered compound is newly added with 10 n by external stress such as shearing.
It means the property of forming a layered structure having a thickness of m or less. Therefore, the cleavable layered compound used in the thermoplastic resin composition of the present invention has a repeating unit length of a periodic structure of 10 or less.
It is preferable that the periodic structure is less than or equal to nm, and it is most preferable that the periodic structure is maintained by an interaction having a relatively small dissociation energy, such as van der Waals force, ionic bond, and hydrogen bond. The layered compound as the component (b) preferably has a particle size that facilitates the formation of a cleavage structure, and from this viewpoint, the average particle size is preferably 0.5 to 100 μm. Above all 0.5
The range is 10 μm, and more preferably the range is 0.5 to 2 μm. The particle size of the layered compound is preferably smaller than the particle size of the thermoplastic resin.

The electrically conductive layered compound of the present invention is
The in-plane specific resistance is 10 ³ Ω · cm or less, preferably 10
Ω · cm or less, more preferably 1 Ω · cm or less. Specific examples include graphite. The graphite is not limited in its degree of graphitization as long as it has a cleavage property. Functional groups such as a hydroxyl group, a carboxyl group and a formyl group can be introduced into the layered compound by a chemical treatment such as ozone treatment, fluorine treatment and electrolytic oxidation treatment. From the viewpoint of reducing the electric resistance of the resin composition, it is preferable that the unit layer has a large spread of the pi-electron conjugated system.

The layered compound having an electromagnetic wave absorbing property of the present invention means a compound having a property of absorbing an electromagnetic wave in a wavelength range of 50 to 10-11 μm. Specific examples thereof include transition metal-containing compounds such as layered transition metal oxyacid salts and transition metal chalcogenides. Examples of the layered transition metal oxygenates include tetratitanates such as K ₂ Ti ₄ O ₉ and KTiNbO.
Examples include titanoniobates such as ₅ ; niobates such as K ₄ Nb ₆ O _17; vanadium pentoxide gel;

As the transition metal chalcogenide, TiS is used.
₂ , ZrS ₂ , NbS ₂ , MoS ₂ , TiSe ₂ , Nb
Se _{2 and} other formulas, that is, MX ₂ [wherein, M represents a transition metal, and X represents S, Se, or Te. ] A transition metal dichalcogenide represented by, TiS ₃ , NbS ₃ , T
aS ₃ , ZrSe ₃ , NbSe ₃ , TaSe ₃ , HfS
The following formulas such as e _{3 and the} like, that is, MX ₃ [wherein M represents a transition metal, and X represents S, Se, or Te. ] The transition metal trichalcogenide etc. which are shown by these can be illustrated. The cleavable layered compound may be a natural product or a synthetic product, and may be used alone or as a mixture of two or more kinds.

In the layered compound of the present invention, when another substance is inserted between the layers of the layered compound, that is, when intercalation is carried out in advance, the layer dispersion becomes extremely good, and the properties of this dispersed layer are extremely effectively exhibited. Therefore, it is preferable.
Preferable examples of the layered compound having the intercalation ability include the layered transition metal oxyacid salts, transition metal chalcogenides and graphite described above. In such a case, 40% by weight or more of the dispersed dispersion layer has a thickness of 1
It is desirable to exhibit a dispersed state of 0 nm or less, and this ratio is preferably 60% by weight or more, and most preferably 70% by weight or more. The compound (hereinafter referred to as “guest”) introduced between layers by intercalation is preferably an organic compound or a molecular compound. Here, the organic compound means a compound containing a carbon atom, and the molecular compound means a compound not containing a carbon atom but capable of forming a molecule.

The above-mentioned guest acts to inhibit the cleavage of the layer,
For example, the type is not limited as long as it does not have a cross-linking action due to a strong chemical bond between layers. Because the main role of this guest is the force between layers to resist the cleavage of layers,
This is because, for example, ionic bonds, hydrogen bonds, coordination bonds, pi-electron interactions, van der Waals forces, etc. between layers are attenuated or substantially eliminated. Specific examples of such guests include organic onium ions and organic compounds such as amines for layered transition metal oxyacid salts; organic onium ions for transition metal chalcogenides; sulfuric acid and bromine for graphite. Molecular compounds such as aluminum chloride, manganese chloride iron chloride, nickel chloride,
Examples thereof include metal chlorides having molecular properties such as copper chloride and cobalt chloride, and metal fluorides having molecular properties such as arsenic pentafluoride and antimony pentafluoride.

Of these, from the viewpoint of maintaining the toughness of the resin composition and thermal stability during melt processing, the preferred guest chemical structure is a layer formed by a strong chemical bond such as a monofunctional ionic bond or covalent bond. Which can be fixed to the cation-exchangeable layer, specifically, an ionic-bonding one such as an organic onium ion for a layer having a cation exchange capacity, which contains a large amount of a hydrophobic structure, more specifically, having 12 or more carbon atoms. Those having an alkyl group can be mentioned. This is because the guest fixed to the layer improves the wettability of the interface with the matrix resin, and relaxes the stress concentration at the interface when stress is applied,
It is presumed that this is due to the effect of maintaining the toughness of the resin composition and the effect that the guest is fixed to the layer and is less likely to be released even when the resin composition is heated and melted.

In the thermoplastic resin composition of the present invention, the higher the degree of fine dispersion of the cleavable layered compound dispersed in the thermoplastic resin of the matrix, the higher the conductivity or electromagnetic wave absorption. According to the experiments conducted by the present inventors, it was found that the content of the cleavable layered compound should be selected in the range of 0.01 to 40% by weight as the ash content. Here, the "ash content" of the layered compound means that about 1.5 g of a sample is precisely weighed,
In a nitrogen atmosphere, heat at 650 ° C for 2 hours to decompose,
It is calculated from the weight of the residue. However, due to the decomposition residue of pure thermoplastic resin previously measured under these conditions,
This is the corrected value. When the content of the layered compound is less than 0.01% by weight as ash content, sufficient conductivity or electromagnetic wave absorption cannot be exhibited, and when it exceeds 40% by weight, the specific gravity becomes large or molding Since the toughness of the product may decrease, neither is preferable. From the viewpoint of imparting functions such as conductivity or electromagnetic wave absorption and reducing the weight, the range of 0.5 to 30% by weight is preferable, more preferably 1 to 20% by weight, and most preferably 2 to 10% by weight. It is a range.

In the thermoplastic resin composition of the present invention, the amount of the cleavable layered compound in the total thermoplastic resin composition should be adjusted so that the ash content of the layered compound is in the range of 0.01 to 40% by weight. It may be selected in the range of 0.01 to 80% by weight. Within this range, the range of 0.5 to 50% by weight is preferable, the range of 0.5 to 30% by weight is more preferable, and the range of 0.5 to 20% by weight is most preferable. When the powder composite is used as a diluting masterbatch, the amount of the cleavable layered compound in the total thermoplastic resin composition is in the range of 10 to 80% by weight, preferably 2%.
It is preferable to select in the range of 0 to 80% by weight, and most preferably 30 to 80% by weight.

In order to effectively achieve the object of the present invention, according to the experiments by the present inventors, the above-mentioned layered compound has an average thickness in the range of 0.1 to 500 nm, and It was found that 5% by weight or more needs to be dispersed in the thickness range of 0.1 to 50 nm. When the average thickness of the layered compound is 500 nm or less, the added layered compound is finely dispersed to more effectively form a conductive path or improve the transmittance of light rays in the ultraviolet region to the infrared region. If it exceeds 500 nm, the effect of imparting such a function and the toughness and surface smoothness of the molded article are deteriorated, which is not preferable. The average thickness of the layered compound is more preferably 0.1 to 200 nm, still more preferably 0.1 to 100 nm within the above range.

In order to effectively achieve the object of the present invention, according to the experiments by the present inventors, further, 5% by weight or more of the whole layered compound is dispersed in a thickness range of 0.1 to 50 nm. I found it necessary to If the amount of the dispersion having a particle size of 50 nm or less is less than 5% by weight, the conductive path is not formed more effectively, and the effect of imparting the function of improving the light transmittance of the ultraviolet region to the infrared region is deteriorated. The layered compound content in the thickness range of 0.1 to 50 nm is preferably 10% by weight or more, and more preferably 30% by weight or more.

In the thermoplastic resin composition of the present invention,
Among the cleavable layered compounds, a conductive compound such as graphite is particularly excellent for the purpose of imparting conductivity, an electromagnetic wave shielding effect and the like. For the purpose of manifesting photochromism and electroism by absorbing electromagnetic waves of a specific wavelength,
Type semiconductors, and tetratitanate, titanoniobate, niobate, etc., which exhibit a behavior similar to titania that absorbs light in the visible region to ultraviolet region having a wavelength shorter than about 415 nm to generate excited electrons, are particularly excellent. ing. The matrix resin in this case is preferably excellent in transparency, and examples of the matrix resin in this case include aromatic polycarbonate resins, acrylic resins, and styrene resins.

When the thermoplastic resin composition of the present invention has conductivity, the electrical resistance is 5 × 1 as a volume specific resistance value.
It is preferably 0 ¹⁴ Ω · cm or less, more preferably 5 × 10 ¹⁰ Ω · cm or less, further preferably 5 × 10 ⁸ Ω · cm or less from the viewpoint of the antistatic effect, from the viewpoint of the electromagnetic wave shielding effect. Is preferably 5 × 10 ⁸ Ω · cm or less.

To produce the thermoplastic resin composition of the present invention, a mixture of a powdery thermoplastic resin and a powdery layered compound is added to a mixture under a temperature condition below the softening temperature of the thermoplastic resin.
It is necessary to apply a shearing force and a compressive force at a shear rate of 500 sec ^-1 or more at the same time. Here, the softening temperature of the thermoplastic resin means the melting point in the case of a crystalline resin, and the glass transition temperature in the case of an amorphous resin. As described above, the thermoplastic resin may be a single kind or a mixture of plural kinds, but in the latter case, the softening temperature of the resin having the lowest softening temperature must be adopted. Further, as the thermoplastic resin, the softening temperature in the case of polyphenylene ether and polyamide, polyolefin and polyamide, aromatic polyester and aromatic polycarbonate, aromatic polyester and polyolefin, polyphenylene ether and polystyrene, etc. usually forms a continuous phase. It means the softening temperature of an ingredient.

The temperature condition lower than the softening temperature of the thermoplastic resin is selected in such a manner that the raw material thermoplastic resin is heated in a range that does not melt and the surface or surface layer of the heated powdery thermoplastic resin is The purpose is to deposit highly cleaved layered compounds. However, the powder composite does not need to have the entire amount of the cleaved layered compound attached to the surface of the thermoplastic resin powder.

A predetermined amount of each of the powdery raw material thermoplastic resin and the powdery layered compound is weighed, and both are well mixed. Then, under heating and stirring, while applying shearing and compressing force at the same time, they are mixed to form a powder composite. An example of a device suitable for this operation is disclosed in Japanese Patent Laid-Open No. 3-42054. In the production of the powder composite, various resin additives, for example, inorganic fillers, metal powders, non-thermoplastic components such as thermosetting resins, etc., within a range not impairing the object of the present invention, A heat stabilizer, an ultraviolet absorber, a pigment, an antioxidant, a plasticizer, an antistatic agent and the like can be added.

The preferred strength and application time during shearing / compression in the production of the powder composite are as follows: type of raw material thermoplastic resin, shape, cleavage of layered compound, average particle size, mixing ratio of the two, Although it varies depending on the temperature conditions and the like, according to the experiments conducted by the present inventors, it was found that a shearing rate and a compressive force of a shearing rate of 500 sec ^-1 or more are required. When the shear rate is less than 500 sec ^-1 , the layered compound is not preferably cleaved, and a powder composite uniformly dispersed and adhered to the surface or surface layer of the thermoplastic resin powder is not preferred. The shear rate range of 500 sec ^-1 or more is preferably 1,000 to 50,000 sec ^-1 ,
More preferably, it is in the range of 5,000 to 40,000 sec ^-1 , and most preferably 8,000 to 35,000 se.
It is in the range of c ⁻¹ . However, excessive shearing and application of compressive force are not preferable because the phase structure of the layered compound may be excessively destroyed and the objects of the present invention such as gas barrier properties may not be effectively achieved.

The powder composite obtained by the above method can be used as it is for the production of the desired molded article. However, the powder composite is further mixed and melted with a thermoplastic resin to produce the desired molded article. Can be used as a thermoplastic resin composition. In the latter case, the above-mentioned various resin additives can be blended within a range that does not impair the object of the present invention. This mixing step is intended to disperse the cleaved layered compound already contained in the powder composite in the thermoplastic resin matrix, not to promote further cleavage by vigorous shear mixing. Because. However, since a better mixing and dispersion is consistent with the gist of the present invention, it is desirable to adopt a method involving relatively strong shearing, such as a twin-screw extruder or Brabender.

Since the thermoplastic resin composition according to the present invention contains a specific layered compound, it has an excellent balance of mechanical strength, elastic modulus, toughness, etc., and has excellent gas barrier properties, surface smoothness of molded products, etc. A molded product can be obtained. Further, when the layered compound has conductivity, a molded product exhibiting conductivity, antistatic effect and electromagnetic wave shielding effect can be obtained. Furthermore, when the layered compound absorbs an electromagnetic wave having a specific wavelength, the coloring property to be developed is smaller than the conventional amount,
Deterioration resistance to electromagnetic waves such as ultraviolet rays and wavelength conversion effect are achieved.

In order to produce a desired molded article from the thermoplastic resin composition according to the present invention, compression molding, injection molding,
A molding technique conventionally known as a molding technique for a thermoplastic resin, such as extrusion molding, blow molding, or calendar molding, can be used. The thermoplastic resin composition according to the present invention,
It has a wide range of uses such as mechanical parts materials, automobile parts materials, electrical equipment housing materials, electromagnetic wave shielding film materials, packaging materials, liquid container materials, optical equipment materials, etc. to manufacture various molded products. Can be useful.

[0043]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In the examples, all transmission electron microscopes (H7000 manufactured by Hitachi, Ltd.)
Type), the thickness of the layered compound (average thickness, and the ratio of the dispersion having a thickness of 0.1 to 50 nm) can be quantified by image analysis by a computer of an image with a magnification of 40,000 to 150,000 (public domain software). NIH Image). The amount of ash was measured by heating and decomposing a sample in which about 1.5 g was precisely weighed for 2 hours at a temperature of 650 ° C. in a nitrogen atmosphere and calculated from the weight of the residue. However, the amount of decomposition residue of pure aromatic polycarbonate was measured and corrected in advance under the same conditions.

[Example 1] Temperature 40 ° C, TH as a solvent
The weight average molecular weight measured by GPC method using F is 4
5,000 aromatic polycarbonate powder (particle size is 250 μm or less), and graphite (KS-15, manufactured by Lonza Co., Ltd.)
The ash content is 1.03% by weight) and 98.5 /
Dry blended at 1.5 (wt%). The obtained dry blend was subjected to a treatment (hereinafter referred to as MF treatment) in which shearing and compressive force were simultaneously applied by a mechanofusion system AM-15F manufactured by Hosokawa Micron Co., Ltd. to obtain a powder composite. The maximum temperature of MF treatment is 1
The temperature was 90 ° C., the time was 20 minutes, and the shear rate was 18,200 sec ⁻¹ . The obtained powder complex was subjected to 280 by a counter-rotating twin screw extruder (Labo Plastomill manufactured by Toyo Seiki Co., Ltd.).
Melt extrusion is performed at a temperature of ℃ (screw rotation = 30 rp
m), pellets were obtained. Using this pellet, a thickness of 2 was obtained by hot pressing (280 ° C. × 3 minutes, pressure: 50 kg / cm ² ).
A 00 μm film was made. The obtained film was measured with an oxygen transmission rate measuring device (OX-TRAN10 / 50H) manufactured by US Modern Control Co., at a temperature of 23 ° C.,
The oxygen transmission rate was measured under the condition of% RH.

Further, a film having a thickness of 870 μm was prepared by the same hot pressing, and the obtained film was Yokogawa-
Using a high resistance meter 4329A manufactured by Hewlett-Packard Co. and a resistance cell 16008A manufactured by the same company, volume specific resistance (unit: Ω · c) after applying voltage for 5 minutes at a temperature of 23 ° C. and an applied voltage of 10V.
m) was measured. Thickness 1 made from hot pressed film
A dumbbell test piece of JIS-K7311 standard is punched out from the mm sheet, and the pulling speed is 20 mm for this test piece.
Tests such as tensile strength and elongation were performed under the condition of / min. The results are shown in Table-1. When the dispersed state of graphite in the matrix resin was observed with a transmission electron microscope, the average thickness of the graphite layer was 350 nm, and the ratio of the graphite layer having a thickness of 0.1 to 50 nm was 10% by weight. The surface of the pressed film was smooth.

[Comparative Example 1] In the example described in Example 1, melt extrusion was performed without MF treatment, and evaluation tests such as tensile strength and elongation were performed in the same procedure as in Example 1 (graphite ash). The amount is 1.05% by weight). The results are shown in Table 1. Further, when the dispersed state of graphite in the matrix resin was observed with a transmission electron microscope, the average thickness of the graphite layer was 950 nm.

[Comparative Example 2] In the example described in Example 1, the same evaluation test was conducted by the same procedure as in the same example except that graphite was not added. The results are shown in Table 1. Further, the powdery aromatic polycarbonate was melt-extruded into resin pellets in the same manner as in Example 1, and then the same hot pressing as in Example 1 was performed to obtain a film having a thickness of 0.1 mm. For the obtained film, when the absorption spectrum of light in the visible region to ultraviolet region of the film was measured,
No absorption was observed in the visible region, and only absorption in the shorter wavelength region than around 300 nm which is a light ray in the ultraviolet region was confirmed.

[0048]

[Table 1] a) The resistance value increased sharply immediately after the voltage was applied, and became infinite in about 15 seconds.

[Example 2] In the example described in Example 1, the mixing ratio of the aromatic polycarbonate powder and graphite (the ash content of graphite is 4.67% by weight) was 95.5 / 4.5.
A hot press film was produced by pelletizing in the same procedure as in the same example except that the content was changed to (wt%). The volume resistivity of the obtained film was measured by the same procedure as in the example, and the result was 4.3 × 10 ⁸ Ω · cm. When the dispersion state of graphite in the matrix resin was observed with a transmission electron microscope, the average thickness of the graphite layer was 250 nm, and the proportion of the graphite layer having a thickness of 0.1 to 50 nm was 20% by weight.

Example 3 Potassium tetratitanate was prepared according to the method described in J.
Ceram. Soc. Japan, Vol. 88,1
It was prepared by the method of Ohta et al. Described in (1980). When a wide-angle X-ray scattering spectrum of this potassium tetratitanate was measured, no peak derived from an impurity crystal was observed. Add this potassium tetratitanate to 4
The procedure of stirring in 1N hydrochloric acid at 0 ° C. for 16 hours, allowing to stand still for one day and then filtering off was repeated 3 times, and then sufficiently washed with water until chloride ions were not detected by the silver nitrate test. The solid thus obtained was confirmed to be tetratitanic acid by flame photo analysis, and was presumed to be tetratitanic acid.

This tetratitanic acid was dispersed in a large excess amount of saturated hydrated dimethyloctylamine, enclosed in an autoclave equipped with a stirring blade, the inside was replaced with nitrogen, and then stirring was continued at a temperature of 120 ° C. for 1 week. The product was thoroughly washed with acetone and air dried. The amine-modified tetratitanic acid thus obtained was subjected to thermogravimetric analysis under a nitrogen stream at a temperature of 450 ° C.,
Since a weight loss of about 30% by weight was observed, it was speculated that dimethyloctylamine was intercalated. This amine-modified tetratitanic acid (ash content is 3.7
7 wt%) 5 wt% and aromatic polycarbonate powder 95
By dry blending with wt%, MF treatment was performed in the same manner as in Example 1 to obtain a powder composite. However, the conditions for the MF treatment are the maximum treatment temperature of 210 ° C., the treatment time of 40 minutes,
The shear rate was 22,100 sec ^-1 .

The obtained powder composite was melt-extruded into resin pellets by the same procedure as in Example 1, and then the pellets were hot-press molded in the same manner as in Example 1 to give a thickness of 0.1 mm. A transparent film was obtained.
When the absorption spectrum of light rays in the visible region to the ultraviolet region of this film was measured, absorption in a wavelength region shorter than around 400 nm was confirmed. Further, when the dispersion state of graphite in the matrix resin was observed by a transmission electron microscope, the average thickness of the dispersion was 40 nm, and the thickness was 0.1 to 5
The proportion of the 0 nm dispersion was 98% by weight, and the proportion of the dispersion having a thickness of 10 nm or less was 80% by weight.

Comparative Example 3 In the example described in Example 3, the amine-modified tetratitanic acid and the aromatic polycarbonate powder were melt-extruded without MF treatment, and the same film forming and evaluation were carried out (amine-modified). The ash content of tetratitanic acid is 3.
75% by weight). As a result, solid particles that can be visually confirmed were scattered on the film, and further, no absorption was observed in the visible light region, and only absorption in the shorter wavelength region than around 300 nm which is the ultraviolet region was confirmed. Further, when observed by a transmission electron microscope in the same manner as in Example 3, only a dispersion having a thickness of about several μm was recognized, which was 5
No dispersed structure of 0 nm or less was observed.

Example 4 Potassium niobate was prepared according to the method described in J. E
retrochem. Soc. , Vol. 116,3
48 (1969) by the method of Nassau et al. This was stirred and dispersed in a large excess of trimethyldodecyl ammonium chloride aqueous solution at a temperature of 60 ° C., and cation exchange was performed for about 1 week. The formed solid was separated by filtration, thoroughly washed with water and air-dried until chloride ion was not detected by the silver nitrate test. 5% by weight of the thus obtained ammonium-modified niobate (ash content: 3.75% by weight) and 95% by weight of an aromatic polycarbonate powder were dry-blended, and MF treatment was carried out by the same procedure as described in Example 3.
Melt extrusion, film forming, and optical absorption spectrum measurement were performed. As a result, the film had a transparent feeling, and absorption of light rays in the visible region to the ultraviolet region similar to that in Example 3 was confirmed. Furthermore, when the resin composition was observed with a transmission electron microscope, the dispersion was obtained. Has an average thickness of 45 nm
The proportion of the dispersion having a thickness of 0.1 to 50 nm was 95% by weight, and the proportion of the dispersion having a thickness of 10 nm or less was 80% by weight.

[Comparative Example 4] In the example described in Example 4, the ammonium-modified niobate (ash content was 3.71% by weight) and the aromatic polycarbonate powder were melt extruded without MF treatment. Film formation and evaluation were carried out in the same procedure as in. As a result, solid particles that can be visually confirmed were scattered on the film, and further, no absorption was observed in the visible region, and absorption of light rays in a wavelength region shorter than around 300 nm which is the ultraviolet region was only confirmed. Further, according to a transmission microscope observation, only a dispersion having a thickness of about several μm was observed, and a dispersion structure of 50 nm or less was not seen.

[0056]

INDUSTRIAL APPLICABILITY The present invention has the following special advantageous effects, and its industrial utility value is extremely large. (1) Since the thermoplastic resin composition according to the present invention contains a specific layered compound, it has an excellent balance of mechanical strength, elastic modulus, toughness, etc., and is excellent in gas barrier properties, surface smoothness of molded products, etc. A molded product can be obtained. (2) When the layered compound has conductivity, a molded product exhibiting conductivity, antistatic effect and electromagnetic wave shielding effect can be obtained. (3) Furthermore, when the layered compound absorbs an electromagnetic wave of a specific wavelength, the coloring property to be expressed with a smaller addition amount than before,
Deterioration resistance to electromagnetic waves such as ultraviolet rays and wavelength conversion effect are achieved.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H05K 9/00 M

Claims (5)

[Claims] 1. A thermoplastic resin composition comprising a thermoplastic resin and a layered compound, wherein the layered compound has conductivity or electromagnetic wave absorption and has an ash content of 0.01 to 40.
Included in the range of wt%, the average thickness is 0.1 to 500n
The thermoplastic resin composition is characterized in that it is in the range of m, and 5% by weight or more of the layered compound is dispersed in the range of 0.1 to 50 nm in thickness. 2. The thermoplastic resin composition according to claim 1, wherein the layered compound is a layered transition metal oxyacid salt or graphite. 3. The layered compound has an organic compound or a molecular compound between layers, and 40% by weight or more of the layered compound is dispersed in a thickness range of 0.1 to 10 nm. Item 3. The thermoplastic resin composition according to Item 1 or 2. 4. A powder mixture of a thermoplastic resin powder and a layered compound powder is subjected to shearing and compression forces of a shearing rate of 500 sec ⁻¹ or more at the same time under a temperature condition lower than the softening temperature of the thermoplastic resin. A method for producing a powder composite or a thermoplastic resin composition, which comprises melt-mixing a thermoplastic resin with the powder composite. 5. An electromagnetic wave shielding molded product formed from the thermoplastic resin composition according to claim 1.