JPH09124836A - Thermoplastic resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition improved in mechanical property and heat property and capable of becoming industrially useful material by melting and kneading a thermoplastic resin with a laminar silicic acid salt previously swollen by a solvent. SOLUTION: This resin composition contains (A) a thermoplastic resin and (B) a laminar silicic acid salt in an amount of 0.01-10 pts.wt. based on 100 pts.wt. of the component A, and the component B dispersed in the component A has 25-1000Å average layer thickness and 20-300 average aspect ratio as a ratio of average particle diameter to average layer thickness. The component B includes preferably a synthetic mica, montmorillonite or vermiculite. The composition can be obtained by melting and kneading, e.g. the component B whose interlayer distance is increased to >=30Å by swelling with water with the component A.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic resin composition comprising a thermoplastic resin and a layered silicate having improved mechanical properties and thermal properties, and a method for producing the thermoplastic resin composition.

[0002]

2. Description of the Related Art Conventionally, in order to improve various properties of a thermoplastic resin, particularly mechanical properties and thermal properties, it has been practiced to mix and knead an inorganic filler. However, if these inorganic fillers are simply melt-kneaded, the dispersion of the inorganic filler in the resin and the interfacial adhesion will be poor, and there will be problems such as reduced impact resistance and poor appearance. Therefore, in order to increase the affinity or binding force between the thermoplastic resin and the inorganic filler, there is a method of subjecting the surface of the inorganic filler to a coupling treatment such as organic silane to improve the dispersion of the filler in the resin. However, the degree of compatibility between the resin and the inorganic filler is improved, and sufficient improvement has not been achieved. Further, with a normal filler, it is necessary to increase the filling amount in order to obtain sufficient strength, which causes a problem that the obtained resin composition has a high specific gravity.

Clay minerals, which are a type of inorganic layered compound, have been used for a long time as fillers, but in ordinary mixing and kneading, secondary agglomeration occurs and the clay minerals are uniformly dispersed in the resin. It was difficult to disperse. Therefore, Japanese Patent Laid-Open No. 63-215775 discloses polymerizing a polymer between layers of clay minerals, but it is still difficult to uniformly disperse the resin and the clay minerals, and the method is also used. There are problems that the type of resin is limited and the process is complicated. In addition, JP-A-6-9313
No. 3 and JP-A-6-41346 disclose that a clay mineral is dispersed in a solvent, while a thermoplastic resin is dissolved in the solvent, and both are mixed in a solution. However, the resin and the clay mineral are also disclosed. It is difficult to disperse the particles uniformly and the process becomes complicated.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that in a thermoplastic resin composition comprising a thermoplastic resin and a layered silicate,
A layered silicate is swollen in advance with a solvent and melt-kneaded with a thermoplastic resin to obtain a thermoplastic resin composition in which the layered silicate is uniformly finely dispersed, and the obtained thermoplastic resin composition. The present inventors have found that the mechanical properties and thermal properties of are greatly improved and have reached the present invention.

That is, in the present invention, (b) layered silicate 0.01 to 1 is added to 100 parts by weight of the thermoplastic resin (a).
In the thermoplastic resin composition containing 0 part by weight, the layered silicate has an average layer thickness of 25 to 1000Å and an average aspect ratio, which is a ratio of the average particle diameter to the average layer thickness, of 20 to 30.
The thermoplastic resin composition is characterized in that it is dispersed at 0, and a layered silicate having an interlayer distance of 30 Å or more is used, and the thermoplastic resin is melt-kneaded with the thermoplastic resin composition. It is a method of manufacturing a product. In particular, it is a method for producing a thermoplastic resin composition, which comprises swelling a layered silicate with water to make the interlayer distance 30 Å or more and melt-kneading the layered silicate with a thermoplastic resin. Furthermore,
A method for producing a thermoplastic resin composition, which comprises swelling a layered silicate with a solvent while applying ultrasonic waves to make an interlayer distance of 30 Å or more and melt-kneading the layered silicate with a thermoplastic resin.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. <Thermoplastic Resin (a)> The thermoplastic resin used in the present invention is not particularly limited as long as it can be melted and molded. As an example, polyamide, polyolefin, polyester, polyacetal,
Examples thereof include polyphenylene sulfide, aromatic vinyl compound polymer, polyphenylene ether, polycarbonate, polysulfone, and liquid crystal polymer.

Polyamide, which is an example of a thermoplastic resin, is
It has a -CO-NH- bond in the polymer main chain and can be melted by heating. A typical example is nylon-
4, nylon-6, nylon-6,6, nylon 4,
6, Nylon-12, Nylon-6, 10 and the like, and other low crystalline polyamides containing a known aromatic diamine, aromatic dicarboxylic acid and other monomer components can also be used. Polyolefin, which is an example of a thermoplastic resin, is a homopolymer of α-olefin, a copolymer of these α-olefins, or a main component of these α-olefins (a plurality of kinds may be used), and if necessary, other unsaturated compounds. Examples thereof include copolymers containing a monomer (a plurality of kinds may be used) as an accessory component. Here, the copolymer may be any type of copolymer such as block, random, graft or composite thereof. Further, these olefin polymers include those modified by chlorination, sulfonation, carbonylation and the like.

The above-mentioned α-olefins are, for example, ethylene, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, and the like, having 2 to 8 carbon atoms because of easy availability. Is preferred. The unsaturated monomer is, for example, an unsaturated organic acid such as (meth) acrylic acid, (meth) acrylic acid ester, maleic acid or the like, or an ester thereof, an anhydride, an unsaturated aliphatic cyclic olefin, or the like. Is mentioned. Specific examples of these polyolefins include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, polybutene, poly-4-methyl-pentene-1, propylene-ethylene block or random copolymer, ethylene and other copolymers. Examples thereof include copolymers with polymerizable monomers.

The polyester, which is an example of the thermoplastic resin, is, for example, a dicarboxylic acid or a lower alkyl ester thereof, an acid halide or an acid anhydride derivative thereof, and a glycol or a dihydric phenol, which are condensed by a conventional method. A thermoplastic polyester produced by the above is included. Specific examples of aromatic or aliphatic dicarboxylic acids suitable for producing this polyester include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid,
Isophthalic acid, p, p'-dicarboxydiphenyl sulfone, p-carboxyphenoxyacetic acid, p-carboxyphenoxypropylene acid, p-carboxyphenoxybutyric acid, p-carboxyphenoxyvaleric acid, 2,6-naphthalene dicarboxylic acid or 2,7. -Naphthalene dicarboxylic acid and the like or a mixture of these carboxylic acids.

As the aliphatic glycol suitable for producing polyester, a straight chain alkylene glycol having 2 to 12 carbon atoms such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol. , 1,12-dodecamethylene glycol and the like are exemplified. Examples of aromatic glycol compounds include p-xylylene glycol, and examples of dihydric phenols include pyrocatechol, resorcinol, hydroxynone, and alkyl-substituted derivatives of these compounds. Other suitable glycols include 1,4-
Also included is cyclohexane dimethanol.

Other preferable polyesters include polyesters obtained by ring-opening polymerization of lactone. For example, polypivalolactone, poly (ε-caprolactone)
And so on. Further, as still another preferable polyester, a polymer (Thermo that forms a liquid crystal in a molten state) is used.
tropic Liquid Crystal Pol
There is polyester as a ymer; TLCP). Typical examples of the polyesters that fall into these categories are X7G manufactured by Suestman Kodak, Xydar (Zyder) manufactured by Dartco, Econol manufactured by Sumitomo Chemical Co., and Vectra manufactured by Celanese.

Among the thermoplastic polyesters mentioned above, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polynaphthalene terephthalate (PEN), poly (1,4-cyclohexanedimethylene terephthalate) (PCT) or liquid crystallinity. Polyester and the like are polyesters suitable for the present invention. The polyacetal which is an example of the thermoplastic resin includes, for example, a high molecular weight polyacetal homopolymer produced by polymerization of formaldehyde or trioxane. The acetal resin produced from formaldehyde has a high molecular weight and has a structure represented by the following formula.

[0013]

Embedded image H—O— (CH ₂ —O—CH ₂ —O) _x —H

Wherein the end groups are derived from a controlled amount of water and x represents a large number (preferably about 1500) of formaldehyde units linked in the form of a head-to-tail bond. In order to increase heat resistance and chemical resistance, it is common practice to convert the terminal group into an ester group or an ether group. The term polyacetal resin also includes polyacetal copolymers. Examples of these copolymers are formaldehyde and monomers or prepolymers of other substances capable of providing active hydrogen, such as alkylene glycols, polythiols, vinyl acetate-acrylic acid copolymers or reduced butadiene. -Block copolymers with acrylonitrile polymers. Formaldehyde and trioxane can be copolymerized with other aldehydes, cyclic ethers, vinyl compounds, ketene, cyclic carbonates, epoxide isocyanurates and ethers. Specific examples of these compounds include ethylene oxide, 1,3
-Dioxane, 1,3-dioxepene, epichlorohydrin, propylene oxide, isobutylene oxide and styrene oxide. Polyphenylene sulfide, which is an example of a thermoplastic resin, has the following structural formula

[0015]

Embedded image

A crystalline resin containing a repeating unit represented by as a main constituent element. Polyphenylene sulfide can be polymerized by polymerizing p-dichlorobenzene in the presence of sulfur and sodium carbonate, or in a polar solvent in the presence of sodium sulfide or sodium hydrosulfide and sodium hydroxide or hydrogen sulfide and sodium hydroxide. Examples of the method include polymerization and self-condensation of p-chlorothiophenol. A method of reacting sodium sulfide and p-dichlorobenzene in an amide solvent such as N-methylpyrrolidone or dimethylacetamide or a sulfone solvent such as sulfolane. Is appropriate. In the present invention, those having the above repeating unit as a main constituent element, that is, a homopolymer comprising the above repeating unit, or a main constituent component (80 mol% or more) thereof, for example, one or two kinds of the following repeating units Copolymers having the above in a proportion of 20 mol% or less can be used.

[0017]

Embedded image

(In the formula, Y represents an alkyl group.) Polyphenylene ether, which is an example of a thermoplastic resin, has the following general formula.

[0019]

Embedded image

(Wherein Q¹Are halogen atom and primary
Alternatively, secondary alkyl group, aryl group, aminoalkyl group
Group, hydrocarbon oxy group or halohydrocarbon oxy group
Then Q ^TwoAre hydrogen atom, halogen atom, primary or young
Is a secondary alkyl group, aryl group, haloalkyl group, charcoal
Represents a hydrogenated oxy group or a halohydrocarbonoxy group, m is
Homopolymerization having a structure represented by a number of 10 or more)
It is a body or a copolymer. Q¹And Q^TwoThe primary alkyl
Suitable examples of groups are methyl, ethyl, n-propyl, n-
Butyl, n-amyl, isoamyl, 2-methylbutyl,
n-hexyl, 2,3-dimethylbutyl, 2-, 3-young
It is preferably 4-methylpentyl or heptyl. Second grade
Suitable examples of the alkyl group include isopropyl and sec-butyl.
Or 1-ethylpropyl. Often Q¹Is
Alkyl or phenyl groups, especially alkyl having 1 to 4 carbon atoms
Is a base, Q^TwoIs a hydrogen atom.

Suitable homopolymers of polyphenylene ether are, for example, those composed of 2,6-dimethyl-1,4-phenylene ether units. Suitable copolymers include the above units and 2,3,6-trimethyl-1,
It is a random copolymer composed of a combination with a 4-phenylene ether unit. Many suitable homopolymers or random copolymers are described in patents and literature. Also suitable are, for example, polyphenylene ethers containing molecular moieties that improve properties such as molecular weight, melt viscosity and / or impact strength. An aromatic vinyl compound polymer, which is an example of a thermoplastic resin, has the following general formula

[0022]

Embedded image

(Wherein R represents hydrogen, a lower alkyl group or halogen, Z represents hydrogen, a lower alkyl group,
It represents chlorine or a vinyl group, and n represents an integer of 1 to 5. ) Is a polymer derived from a compound having a structure represented by As an example, polystyrene, rubber-reinforced polystyrene, styrene-acrylonitrile copolymer,
Examples thereof include acrylonitrile-butadiene-styrene copolymer, styrene-maleic anhydride copolymer, styrene-maleimide copolymer and the like.

Examples of the polycarbonate which is an example of the thermoplastic resin include aromatic polycarbonate, aliphatic polycarbonate, and aliphatic-aromatic polycarbonate.
Among them, aromatic polycarbonates composed of bisphenols such as 2,2-bis (4-oxyphenyl) alkane type, bis (4-oxyphenyl) ether type, bis (4-oxyphenyl) sulfone, sulfide or sulfoxide type are preferable. Further, if necessary, a polycarbonate resin composed of bisphenols substituted with halogen can also be used. The molecular weight of polycarbonate is not limited, but generally 10,000 or more,
It is preferably 20,000 to 40,000. Polysulfone, which is an example of a thermoplastic resin, has the structure

[0025]

[Chemical 6]

(T in the formula is an oxygen atom, a sulfur atom, or an aromatic diol residue.) And has at least some units.

[0027]

Embedded image

Those having any one of the repeating units of Among these thermoplastic resins, polyamides, polyesters, polyolefins, polyphenylene sulfides, polyphenylene ethers, polycarbonates and aromatic vinyl compound polymers are preferable, and polyolefins and polyphenylene ethers are more preferable. In addition, these thermoplastic resins may be used alone or in combination of two or more kinds.

The thermoplastic resin used in the present invention is 25
The melt viscosity measured at ⁰ to 300 ° C. and a shear rate of 100 to 1000 SEC ⁻¹ is preferably 3000 Poise or less, or 10000 Poise or more, more preferably 2000 Poise or less, or 30000.
Poise or higher, particularly preferably 1000 Pois
e or less, or 50,000 Poise or more.

<Layered silicate (b)> The layered silicate used in the present invention may be a layered phyllosilicate mineral composed of a layer of magnesium silicate or aluminum silicate. Specific examples include smectite clay minerals such as montmorillonite, savonite, beidellite, nontronite, hectorite, and stevensite, mica, talc, vermiculite, and virosite, and these are natural. It may be a synthesized one. Among these, synthetic mica, montmorillonite and vermiculite are preferable.

The layered silicate used in the present invention is
Those treated with a swelling agent are preferred in order to facilitate swelling in a solvent. Examples of the swelling agent of the present invention include ammonium salts, pyridinium salts and sulfonium salts, which are onium salts having an onium ion group in the molecule. More specifically, those having octadecyl ammonium ion, monomethyl octadecyl ammonium ion, dimethyl octacyl ammonium ion, dodecyl ammonium ion, 6-amino-n-caproate ion, 12-aminododecanoate ion can be exemplified. However, when swelling with water, untreated layered silicate swells more easily, so it is preferable not to treat with a swelling agent.

In the present invention, the swelling means a phenomenon that the layered silicate absorbs the solvent to increase the volume thereof, and the preferable combination for the swelling is the swelling degree of 1 cc /
g or more of a combination of a layered silicate and a solvent. There are various methods for measuring the degree of swelling, and the degree of swelling may be determined by the ratio of the volume obtained by the sedimentation volume method (clay handbook, page 513) and the weight of the layered silicate in an absolutely dry state. If the swelling properties of the layered silicate and the solvent are very good, the layered silicate will be super-dispersed in the solvent and will not sediment due to gravity, making measurement impossible. Of course, also in this case, the combination of the layered silicate and the solvent which swells very well.

Here, the solvent used for swelling the layered silicate is
Any liquid may be used at room temperature, and there is no particular limitation. For example, aromatic hydrocarbons such as benzene, toluene, xylene; chain and cyclic aliphatic hydrocarbons such as heptane, cyclohexane; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene, trichlorobenzene, dichloromethane; dioxane, diethyl ether, etc. Ethers; acetone, cyclohexanone, methyl ethyl ketone, acetophenone, etc. ketones; ethyl acetate, propiolactone, etc. esters; acetonitrile, benzonitrile, etc. nitriles; methanol, ethanol, propanol, butanol, ethylene glycol, diethylene glycol, etc. Alcohols; other than these, water, nitrobenzene, sulfolane, dimethylformamide, dimethylsulfoxide and the like can be mentioned. These may be used alone or as a mixture. Preferably aromatic hydrocarbon, halogenated hydrocarbon,
Alcohols and water, particularly preferred are solvents such as xylene, toluene, dichlorobenzene, trichlorobenzene, methanol, ethanol and water, and particularly preferred are water.

Here, the amount of the solvent used for swelling the layered silicate is a weight ratio of the layered silicate; the solvent is 1: 0.5.
˜1: 100, more preferably 1: 2 to 1:80, and even more preferably 1: 4 to 1:60.
It is. If it is less than 1: 0.5, the swelling is insufficient and the interlayer distance is short, and if it exceeds 1: 100, melt-kneading is difficult.
In the present invention, the interlayer distance of the swollen layered silicate is preferably 30 Å or more, and more preferably 50.
It is Å or more, more preferably 70 Å or more, and particularly preferably 90 Å or more. When the interlayer distance is less than 30Å, the layered silicate is not evenly dispersed in the resin.

The method for swelling the layered silicate with a solvent is not particularly limited, and various methods can be used. As an example, a method of mixing both using a stirring tank, a method of mixing both using a blender, a method of mixing both using a high speed mixer such as a Henschel mixer, and the like can be used. Further, at this time, it is preferable to mix while applying ultrasonic waves in order to increase the degree of swelling and to make the layered silicate uniformly dispersed. As an example, the layered silicate and the solvent can be stirred for 2 to 10 hours using the closed tank with the ultrasonic oscillator shown in FIG.

<Composition ratio of constituents> Thermoplastic resin (a)
The amount of the layered silicate (b) is 0.0 with respect to 100 parts by weight.
The amount is 1 to 10 parts by weight, preferably 0.02 to 9 parts by weight, and particularly preferably 0.03 to 7 parts by weight. The layered silicate (b) was added to 100 parts by weight of the thermoplastic resin (a).
If it is less than 0.01 parts by weight, the rigidity and heat resistance are unsatisfactory, and if it exceeds 10 parts by weight, moldability and appearance are difficult.

<Form of Composition> In the present invention, the layered silicate in the thermoplastic resin composition has an average layer thickness of 25 to 10
00Å, average aspect ratio 20 to 300 are dispersed, preferably average layer thickness 25 to 500 Å, average aspect ratio 30 to 200, more preferably average layer thickness 25 to 300 Å, average aspect ratio 50 to 100. . If the average layer thickness exceeds 1000Å and the average aspect ratio is less than 20, the effect of improving mechanical properties and thermal properties is insufficient. If the average layer thickness is less than 25Å and the average aspect ratio exceeds 300, it is difficult to produce. .

<Additional component> Other additional components can be added to the thermoplastic resin composition according to the present invention.
For example, known antioxidants, weather resistance improvers, nucleating agents, flame retardants, impact resistance improvers, plasticizers, flow improvers; or organic / inorganic fillers other than layered silicates, reinforcing agents, especially Addition of glass fiber, potassium titanate, calcium carbonate, silica, etc. is effective in improving rigidity, heat resistance, dimensional accuracy, and the like. For practical use, various colorants and dispersants thereof may be known ones.

<Manufacturing and Molding Method of Composition> As the melt-kneading machine for obtaining the thermoplastic resin composition of the present invention, a kneading machine generally used for thermoplastic resins can be applied. For example, a single-screw or multi-screw kneading extruder, a roll, a Banbury mixer, etc. may be used.

In the present invention, it is preferable that the kneading machine is provided with a ventro and the ventro is kept at a reduced pressure during the melt kneading. At least a part of the resin in the kneader should be melted in the front part of the ventro so that it can be vacuum-sealed. If the resin in the kneading machine is held in a molten state for a long time before reaching the ventro, the impact resistance is deteriorated. Therefore, it is preferable to melt the resin immediately before reaching the ventro as far as possible. The vacuum device directly connected to the ventro may have its capability selected depending on the degree of pressure reduction of the ventro, and its type and the like are arbitrary.

The pressure of the ventro is preferably 200 Torr or less, more preferably 100 Torr or less, and particularly preferably 50 Torr or less. Bentoro pressure is 200
If it is larger than torr, heat resistance and molding appearance are unsatisfactory. The content of the solvent in the final composition is preferably 1% by weight or less, more preferably 0.9% by weight or less, and particularly preferably 0.5% by weight or less. If the solvent in the final composition exceeds 1% by weight, heat resistance and appearance are unsatisfactory. The order of kneading may be to knead all the components at the same time, or to knead using a preliminarily kneaded blend, or to feed and knead each component sequentially from the middle of the extruder. In particular, when the property of the layered silicate / solvent mixture is liquid, it is preferable to feed it from the middle of the extruder using a liquid addition pump.

[0042] In the present invention, the shear rate at the extruder is preferably 200 sec ^-1 or more, more preferably 300 sec ^-1 or more, more preferably 4
00 SEC ^-1 or more, particularly preferably 500 SEC ^-1
That is all. The molding method of the thermoplastic resin composition of the present invention is not particularly limited, and molding methods generally used for thermoplastic resins, that is, injection molding, hollow molding, extrusion molding, sheet molding, thermoforming, rotation Molding methods such as molding, lamination molding and press molding can be applied.

[Examples and Comparative Examples] The present invention will be described in detail below with reference to Examples. The components used are as follows. Thermoplastic resin (a) (a-1) Polybutylene terephthalate (Mitsubishi Chemical Co., trade name: Novadour 5010) (a-2) Polyamide 6 (Mitsubishi Chemical Co., trade name: Novamid 1020) (a-3) Polypropylene ( Mitsubishi Chemical Co., Ltd. product name: Nobrene TA8) (a-4) Poly (2,6-dimethyl-1,4-phenylene ether) (Nippon Polyether Co., Ltd., intrinsic viscosity of 0.44 dl / measured in chloroform at 30 ° C.) g)

Layered silicate (b) (b-1) Synthetic mica (trade name of Corp Chemical)
ME100 Swelling agent untreated) (b-2) Synthetic mica (manufactured by Corp Chemical)
MAE swelling agent treatment)

Other Filler Talc (Fuji Talc Co., Ltd. product name: KT300) Swelling solvent xylene Commercially available xylene (reagent grade) water Pure water In addition, for evaluation, each physical property value and various characteristics were measured by the following methods, The results are shown in Table-1.

(1) Interlayer distance of layered silicate The layered silicate was attached to an aluminum powder sample holder,
An X-ray diffractometer (rotor flex) manufactured by Rigaku Denki Co., Ltd. is used to measure the diffraction intensity at a diffraction angle of 0 to 10 degrees using CuKα as a radiation source. Corresponding to the distance between layers (00
1) plane diffraction peak position (6.5 for unswelled layered silicate)
The layer distance was calculated using the formula of Black). The measurement conditions were: tube voltage: 40 kV, tube current: 250 mA, slit system: 1 / 2-1 / 2-0.1.
5 degrees.

(2) Dispersion morphology A part of the molded product was cut out, an ultrathin section was prepared using an ultramicrotome, and observed with a transmission electron microscope (JEM2010) manufactured by JEOL Ltd. The dispersed morphology of the layered silicate was confirmed. From the observed photograph, the size in the thickness direction of the silicate dispersed in the resin and the size in the direction perpendicular to it are calculated by an image analyzer (Spica 2 manufactured by Nippon Avionisque), and the aspect ratio is calculated from the ratio. It was These values were measured for 100 or more silicates dispersed in the resin, and a number average value was obtained for each.

(3) Flexural Modulus ISO R178-1974 Procedure 1
According to 2 (JIS K7203), it measured using the Instron tester. (4) Heat distortion temperature Using an HDT tester manufactured by Toyo Seiki Seisakusho, JIS
It was measured according to K7207 under a load of 18.6 kg. (5) Density The water density was measured according to JIS K7112.

[Example-1] The components (b) and the solvent were sufficiently mixed and stirred in an autoclave in the proportions shown in Table 1 while applying ultrasonic waves to swell the components (b) in the solvent.
Next, the layered silicate swollen in the above step was sufficiently mixed and stirred with the thermoplastic resin (a) at a compounding ratio shown in Table 1 using a super mixer. Next, this is T made by Japan Steel Works
Using an EX44 twin-screw extruder, melt kneading under a kneading condition of a set temperature of 230 ° C. and a screw rotation speed of 350 rpm, and melt kneading under a reduced pressure condition (ventro pressure 10 Torr) with a ventro installed downstream from the kneading part. Then, the composition was prepared and pelletized.

From the pellets of the above resin composition, an in-line screw type injection molding machine (J100 manufactured by Japan Steel Works, Ltd.) was used.
Mold), cylinder temperature 280 ° C., mold cooling temperature 6
Injection molding was performed at 0 ° C to prepare a test piece. During injection molding, use a vacuum dryer until immediately before,
It was dried for 48 hours under the conditions of 0.1 mmHg and 80 ° C. The injection-molded test pieces were placed in a desiccator immediately after molding, allowed to stand at 23 ° C. for 4 to 6 days, and then evaluated, and the results are shown in Table 1.

[Example-2] [Example-] except that polybutylene terephthalate (a-1) was used as the thermoplastic resin and the cylinder temperature of the injection molding machine was 260 ° C.
The same operation as 1) was performed. The results are shown in Table 1. [Example-3] Polyamide (a-
The same operation as in [Example-1] was performed except that 2) was used. The results are shown in Table 1.

Example 4 Polypropylene (a-3) was used as the thermoplastic resin, and the layered silicate and the solvent were
1, except that the temperature of the twin-screw extruder was set to 180 ° C., the cylinder temperature of the injection molding machine was set to 220 ° C., and the mold cooling temperature was set to 40 ° C. went. The results are shown in Table 1.

[Example-5] The components (b) and the solvent were sufficiently mixed and stirred in a supermixer in the proportions shown in Table 1 to swell the components (b) in the solvent. Then, using a TEX44 twin-screw extruder manufactured by Japan Steel Works, a set temperature of 18
Adjusted in the above step while melt-kneading the thermoplastic resin under kneading conditions of 0 ° C. and screw rotation speed of 350 rpm,
The swollen layered silicate was added directly to the kneading part using a pump, melt-kneaded under the condition of a pressure of 10 V tontro installed downstream from the kneading part to form a composition, and then pelletized. Molding evaluation is [Example-4]
The same was done. The results are shown in Table-1.

[Comparative Example-1] The procedure of [Example-1] was repeated except that no solvent was used. The results are shown in Table 1. [Comparative Example-2] The same procedure as in [Example-1] was performed except that ultrasonic waves were not applied when the component (b) was swollen with a solvent. The results are shown in Table 1.

[Comparative Example-3] The procedure of Example-3 was repeated, except that talc was used as an inorganic filler instead of the component (b) and no solvent was used. Table 1 shows the results. [Comparative Example-4] The same procedure as in [Example-4] was carried out except that talc was used as an inorganic filler instead of the component (b) and no solvent was used. Table 1 shows the results.

[Comparative Example-5] The same procedure as in [Example-5] was carried out except that the amounts of solvent were changed to those shown in Table-1. The results are shown in Table 1. [Comparative Example-6] Except that the amount of solvent was changed to the amount shown in Table-1,
It carried out like [Example-5]. Melt kneading was impossible.

[Comparative Example-7] The same components (a) and (b) as in [Example-1] were mixed in a solution of 200 parts by weight of a xylene solvent and sufficiently stirred, and then xylene as a solvent was removed. After the solvent was added to form the composition, the mass of the composition was crushed by a crusher to give pellets having a diameter of 2 to 3 mm. Thereafter, molding and evaluation were performed in the same manner as in [Example-1]. Table 1 shows the results.

[Comparative Example-8] The same procedure as in [Example-5] except that a layered silicate treated with a swelling agent (dimethyl distearyl ammonium chloride salt) was used as the component (b) and water was used as the solvent. Molding and evaluation were performed. The results are shown in Table 1.

[0059]

[Table 1]

[0060]

From the results of the above evaluation test, the composition of the present invention is excellent in rigidity and heat resistance, and according to the production method of the present invention, the layered silicate is extremely finely dispersed in the thermoplastic resin, It can be seen that the obtained thermoplastic resin composition has a significantly improved mechanical and thermal properties with a small amount of filler. Therefore, according to the present invention, low specific gravity and high rigidity,
A high heat resistant thermoplastic resin composition can be produced, its use is wide, and it can be an industrially useful material.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a closed tank with an ultrasonic oscillator used in the present invention. (Material: SUS304, capacity 2
Liter, pressure resistance: 2 kg / cm ² )

[Explanation of symbols]

 1 sample inlet 2 stirrer 3 safety valve and pressure gauge 4 jacket 5 PZT oscillator

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hironari Sano 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Chemical Co., Ltd. Yokkaichi Research Institute

Claims (4)

[Claims] 1. A thermoplastic resin composition containing 0.01 to 10 parts by weight of a layered silicate (b) per 100 parts by weight of a thermoplastic resin (a), wherein the layered silicate has an average layer thickness. Is 25 to 1000Å, and the average aspect ratio, which is the ratio of the average particle size to the average layer thickness, is dispersed at 20 to 300. 2. The method for producing a thermoplastic resin composition according to claim 1, wherein a layered silicate having an interlayer distance of 30Å or more is used as the component (b), and the thermoplastic resin is melt-kneaded. . 3. The thermoplastic resin composition according to claim 2, wherein the component (b) is swollen with water to have an interlayer distance of 30 Å or more and the thermoplastic resin is melt-kneaded. Production method. 4. The component (b) is swollen with a solvent while applying an ultrasonic wave so that the interlayer distance is 30 Å or more,
The method for producing a thermoplastic resin composition according to claim 2, wherein this and a thermoplastic resin are melt-kneaded.