JP2000309687A - Polyester resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for simply and safely obtaining a resin composition excellent in mechanical characteristics and heat resistance by finely dispersing inorganic particles into a polyester resin. SOLUTION: This method for producing a polyester resin composition containing a thermoplastic polyester resin and inorganic particles comprises a step for kneading the thermoplastic polyester resin with a mixture comprising inorganic particles and water. In the step, the concentration of inorganic particles in the mixture is higher than a concentration obtained when the mixture exhibits liquid limit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polyester resin composition containing a thermoplastic polyester resin and inorganic particles.

[0002]

2. Description of the Related Art Thermoplastic polyester resins are excellent in mechanical properties, heat resistance, electrical properties, chemical resistance and weather resistance, and are used for various purposes such as electric / electronic parts, mechanical parts, OA equipment parts, and home electric appliance parts. Widely used in various structural parts fields. In recent years, as structural parts have become thinner and more complex,
There is a demand for ensuring a high level of balance between mechanical properties, heat resistance, dimensional stability and surface properties.

As a measure for improving the above-mentioned balance of various physical properties, the present inventors disclosed in WO 97/44343 (1997) that a silane compound was introduced into a swellable silicate swollen in a solvent. A technique relating to a polyester resin composition obtained by polymerizing a silane clay composite and a dispersion containing a diol compound such as bishydroxyalkyl terephthalate as an essential component is disclosed. According to this technique, the silane clay composite is uniformly and finely dispersed in the form of a thin plate at the nanometer (nm) level in the polyester resin composition, whereby the mechanical properties and heat resistance are balanced at a high level. However, the preparation and polymerization of the above-mentioned dispersion require a great deal of time and labor, and have caused high costs. Accordingly, there has been a demand for a method for easily and finely dispersing inorganic particles such as swellable silicate to produce a polyester resin composition having excellent physical properties.

In an attempt to easily finely disperse the inorganic particles in the resin, a vent-type molding machine is used. The water and / or the boiling point of the inorganic particles having an average particle size of 0.01 to 5 μm are not more than 200 ° C. (Japanese Unexamined Patent Publication No. 3-115352). According to the above method, the inorganic particles are certainly finely dispersed in the polyester resin, and if the polyester resin is used for a film, characteristics such as slip characteristics can be seen, but even when used as a molding material, an excellent balance of physical properties can be obtained. It is not as effective as it is expressed. In addition, the slurry generally means a fluid obtained by mixing a solid (inorganic particles) and a liquid (solvent) (JIS M0104), that is, a fluid suspension. In this case, the inorganic particles immediately settle and separate due to a difference in specific gravity between the solvent such as water and the inorganic particles, and thus lack storage stability. Therefore, even if a slurry in which the inorganic particles are settled or separated is added to and kneaded with the resin, the inorganic particles are not uniformly dispersed, and in some cases, the quality is reduced by the aggregated particles. Therefore, in order to utilize the above-mentioned conventional technology, it is necessary to stir the slurry and disperse the settling particles immediately before adding and kneading the slurry to the resin, which is problematic in operation.

As another attempt of fine dispersion, a method of melt-kneading a layered silicate and a thermoplastic resin having an interlayer distance of 30 ° or more by swelling with water or the like (Japanese Patent Laid-Open No. 9-12483).
No. 6). Specifically, swellable mica is used as a layered silicate, and swellable mica swelled with water or alkylammonium-treated swellable mica swelled with xylene is biaxially extruded with polypropylene or the like. A technique for performing this is disclosed. However, according to the above technique, the layered silicate is finely dispersed only partially in the resin and is not uniformly dispersed in the entire resin system, so that a resin composition having desired physical properties cannot be obtained. Furthermore, when swellable mica treated with an alkylammonium salt or the like is used, another problem such as deterioration in physical properties or coloring occurs due to deterioration of the polyester resin.

As another attempt, there is a method of kneading a mixture of an organic solvent and a layered silicate with a crystalline thermoplastic resin (JP-A-9-48856).
A technique is disclosed in which swellable mica treated with an organic ammonium salt or the like is used as a layered silicate, trichlorobenzene or the like is used as an organic solvent, and a mixture of the two and polypropylene or the like are biaxially extruded. However, in the above technique, in addition to the problem of resin deterioration due to ammonium salts, depending on kneading conditions, the used organic solvent may remain in the system, and a problem may occur in terms of quality and safety and health of the obtained resin composition. is there.

[0007] As described above, at present, there has not yet been provided a production technique for easily and safely obtaining a resin composition having excellent mechanical properties and heat resistance by finely dispersing inorganic particles in a polyester resin.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to improve the above-mentioned conventional problems, and to reduce the inorganic particles by a simple method without causing problems such as resin deterioration and remaining organic solvent. It is an object of the present invention to provide a method for producing a polyester resin composition which is uniformly finely dispersed in the inside thereof and has an excellent balance of physical properties such as mechanical properties and heat resistance.

[0009]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have reached the present invention.
That is, by increasing the concentration of the inorganic particles in the mixture of water and the inorganic particles to be higher than the concentration at which the mixture exhibits the liquidity limit, the fluidity of the mixture is eliminated and the sedimentation / separation of the inorganic particles is suppressed, We have found a production method in which such a mixture is added to a thermoplastic polyester resin and melt-kneaded.

The method of the present invention is a method for producing a polyester resin composition containing a thermoplastic polyester resin and inorganic particles, comprising a step of kneading a thermoplastic polyester resin with a mixture containing inorganic particles and water. A process for producing a polyester resin composition, wherein the concentration of the inorganic particles in the mixture is higher than the concentration at which the mixture exhibits a liquid limit. Thereby, the above object is achieved.

In one embodiment, the inorganic particles are prepared by adding a swellable silicate swelling in a solvent to the following general formula (1): Y _n SiX _4-n (1) (where n is 0 to 0) X is an integer of 3; Y is an optionally substituted hydrocarbon group having 1 to 25 carbon atoms;
Is a hydrolyzable group and / or a hydroxyl group; n Y and 4-n X may be the same or different.
Is a silane clay composite prepared by introducing a silane compound represented by the formula:

In another aspect, the present invention provides a polyester resin composition containing a thermoplastic polyester resin obtained by the above method and inorganic particles.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

The present invention relates to a method for producing a polyester resin composition containing a thermoplastic polyester resin and inorganic particles, which comprises a step of kneading a thermoplastic polyester resin with a mixture containing inorganic particles and water. Here, a method for producing a polyester resin composition, wherein the concentration of the inorganic particles in the mixture is higher than the concentration at which the mixture exhibits a liquid limit.

The content of the thermoplastic polyester resin in the polyester resin composition is preferably 99.5% by weight to 70% by weight, more preferably 99% by weight to 75% by weight, and most preferably 98.5% by weight. ~ 80% by weight. The content of the inorganic particles in the polyester resin composition is preferably 0.5% by weight to 30% by weight, more preferably 1.0% by weight to 25% by weight, and most preferably 1.5% by weight to 25% by weight. 20% by weight.

The thermoplastic polyester resin used in the present invention includes an acid component containing a dicarboxylic acid compound and / or an ester-forming derivative of dicarboxylic acid as a main component,
Any conventionally known thermoplastic polyester resin obtained by reaction with a diol component containing a diol compound and / or an ester-forming derivative of the diol compound as a main component.

Examples of the above dicarboxylic acid compounds include terephthalic acid, isophthalic acid, orthophthalic acid,
2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 4,4′-diphenyletherdicarboxylic acid, 4,4′-diphenylmethanedicarboxylic acid,
4,4'-diphenylsulfonedicarboxylic acid, 4,4 '
Aromatic dicarboxylic acids such as -diphenylisopropylidene dicarboxylic acid; and their substituted products (for example, alkyl group-substituted products such as methyl isophthalic acid) and derivatives (dimethyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, etc.). Such as alkyl ester compounds)
Can also be used. Also, oxyacids such as p-oxybenzoic acid and p-hydroxyethoxybenzoic acid and their ester-forming derivatives can be used. Two or more of these monomers may be used as a mixture. If the amount is small enough not to impair the properties of the obtained polyester resin composition, one or more aliphatic dicarboxylic acids such as adipic acid, azelaic acid, dodecane diacid, sebacic acid and the like are used together with these aromatic dicarboxylic acids. Can be used in combination.

Among the above-mentioned acid components, terephthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4 ′ are preferred in view of the crystallinity, strength and elastic modulus of the obtained thermoplastic polyester resin.
-Biphenyldicarboxylic acids and their ester-forming derivatives are preferred.

Examples of the diol compound include aliphatic glycols such as ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, and neopentyl glycol; and fatty acids such as 1,4-cyclohexanedimethanol. Aromatic diols such as cyclic glycols, 1,4-phenylenedioxydimethanol can be used. Cyclic esters such as ε-caprolactone may also be used. Two or more of these may be used as a mixture. Furthermore, if the amount is small enough not to significantly lower the elastic modulus of the obtained polyester resin, long-chain diol compounds (eg, polyethylene glycol, polytetramethylene glycol), and alkylene oxide addition polymers of bisphenols, etc. For example, an ethylene oxide addition polymer of bisphenol A) may be used in combination.

Among the above-mentioned diol components, ethylene glycol, butylene glycol, 1,4
-Cyclohexanedimethanol is preferred.

The term "main component" means that the proportion of each compound or derivative in the acid component or diol component is 80% or more, and more preferably 90% or more. Of course, it may be 100%.

Specific examples of the thermoplastic polyester resin include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, and polycyclohexane-1,4.
-Dimethyl terephthalate, neopentyl terephthalate, polyethylene isophthalate, polyethylene naphthalate, polybutylene naphthalate, polyhexamethylene naphthalate and the like. Further, a copolymerized polyester produced by using two or more kinds of acid components and / or diol components used for producing these resins may be mentioned.

The above-mentioned thermoplastic polyester resins may be used alone or in combination with polyester resins having different compositions or components and / or polyester resins having different intrinsic viscosities.
More than one species may be used in combination.

Among the above polyester resins, polyethylene terephthalate, polybutylene terephthalate, polycyclohexane-1,4-dimethyl terephthalate, and polyethylene naphthalate are preferred in view of strength, elastic modulus, cost, and the like.

The molecular weight of the thermoplastic polyester resin is preferably such that the logarithmic viscosity measured at 25 ° C. using a phenol / tetrachloroethane (5/5 weight ratio) mixed solvent is preferably 0.3 to 2.0 (dl / g). , More preferably 0.3 to 1.8 (dl / g), still more preferably 0.3 to 1.5 (dl / g), and particularly preferably 0.3 to 1.2 (dl / g). dl / g). 0.3 logarithmic viscosity
(Dl / g), the mechanical properties and impact resistance of the obtained polyester resin composition are low,
If it is larger than (dl / g), the melt viscosity tends to be high and the molding fluidity tends to decrease.

In other words, in the case of polyethylene terephthalate, for example, the viscosity is preferably 25,000 to 200,000, more preferably 25,000 to 180,000, more preferably 25,000 to 180,000 in terms of weight average molecular weight. Is 25,000 to 150,000.

The mixture containing inorganic particles and water (hereinafter referred to as “inorganic particle-water dispersion”) used in the present invention is not particularly limited, and is a mixture of conventionally known inorganic particles and water. It is obtained by doing.

Specific examples of the above-mentioned inorganic particles include swellable silicates such as smectite clay and swellable mica, non-swellable silicates such as talc and kaolinite, silicon oxide compounds, titanium oxide and silicate. Calcium, calcium carbonate, α-, β-, γ-, δ-alumina, iron oxide, zinc oxide, magnesium carbonate, calcium phosphate, barium sulfate, calcium sulfate, and these may be used alone or in combination of two or more. used.

Among the inorganic particles, swellable silicates are preferably used. The swellable silicate used in the present invention is mainly composed of a tetrahedral sheet of silicon oxide and an octahedral sheet of metal hydroxide, and a layered silicate having exchangeable cations between layers. means.

Among the swellable silicates, the smectite group clay is defined by the following general formula (2): X _0.2 to _0.6 Y ₂ to ₃ Z ₄ O ₁₀ (OH) ₂ .nH ₂ O (2) X is K, Na, 1 / 2Ca, and 1 / 2M
g is at least one member selected from the group consisting of
At least one selected from the group consisting of Fe, Mn, Ni, Zn, Li, Al and Cr, and Z is at least one selected from the group consisting of Si and Al. Note that H
₂ O represents water molecules bound to interlayer ions, while n varies significantly depending on interlayer ions and relative humidity. )
It is a natural or synthetic clay represented by Specific examples of the smectite group clay include, for example, montmorillonite, beidellite, nontronite, saponite, iron saponite, hectorite, sauconite, stevensite, bentonite, and the like, or their substituted products, derivatives, and mixtures thereof. . The distance between the bottom surfaces of the smectite group clay in the initial coagulated state is about 10 to 17 °, and the average particle size of the smectite group clay in the coagulated state is about 1000 ° to 1,000,000 °.
It is.

Here, the bottom surface interval value means the distance between the bottom surfaces of the unit layers of the swellable silicate or the obtained silane clay composite. Specifically, the bottom surface interval can be confirmed by small angle X-ray diffraction (SAXS) or the like. That is, an X-ray diffraction peak angle value of a dispersion comprising a dispersion medium and a swellable silicate (or a swellable silicate in an aggregated state before being added to the dispersion medium) is measured by SAXS, and the peak angle is measured. By substituting the value into Bragg's formula 2 dsin θ = nλ (where d is the bottom surface interval in the crystal, θ is the incident angle, n is a positive integer, and λ is the wavelength of the X-ray),
Find the base spacing value. Similarly, by measuring the initial distance between the bottom surfaces of the layered silicate and comparing the two values, it is possible to confirm the enlargement of the distance between the bottom surfaces.

In the present specification, the initial distance between the bottom surfaces of the swellable silicate means the distance between the bottom surfaces of the swellable silicate in which unit layers are stacked and aggregated before being added to the dispersion medium. .

The swellable mica is represented by the following general formula (3): X _0.5 to _1.0 Y ₂ to ₃ (Z ₄ O ₁₀ ) (F, OH) ₂ (3) (where X is Li, Na , K, Rb, Ca, Ba, and Sr, and Y is at least one selected from the group consisting of Mg, Fe, Ni, Mn, Al, and Li; Is Si, Ge, Al,
At least one selected from the group consisting of Fe and B. ) Is a natural or synthetic mica. These have the property of swelling in water, a polar solvent compatible with water at an arbitrary ratio, and a mixed solvent of water and this polar solvent,
Specific examples include, for example, lithium-type teniolite, sodium-type teniolite, lithium-type tetrasilicon mica, sodium-type tetrasilicon mica, and the like, or a substituted product, a derivative, or a mixture thereof. The distance between the bottom surfaces of the swellable mica in the initial aggregation state is approximately 10 to 17 °, and the average particle size of the swellable mica in the aggregation state is about 1000 to 1,000,000 °.

Some of the above-mentioned swellable mica have a structure similar to that of vermiculites, and such equivalents of vermiculites can also be used in the present invention. As the vermiculite such equivalent, there are three octahedral type and dioctahedral the following general formula (4) (Mg, Fe, Al) 2 ~ 3 (Si 4-x Al x) O 10 (OH) 2 (M ⁺ , M ²⁺ _1/2 ) _x · nH ₂ O (4) (where M is an exchangeable cation of an alkali or alkaline earth metal such as Na or Mg, and x = 0. 6-0.
9, n = 3.5 to 5). In the initial state of aggregation of the above vermiculite-equivalent product, the interval between the bottom surfaces is approximately 10 to 17 °, and the average particle size in the aggregated state is approximately 1000 to 5,000,000 °.

The crystal structure of the swellable silicate is desirably high in purity, which is regularly stacked in the c-axis direction. However, a so-called mixed layer mineral in which the crystal cycle is disordered and a plurality of types of crystal structures are mixed is also used. Can be used.

The swellable silicate may be used alone,
Two or more kinds may be used in combination. Among these, montmorillonite, bentonite, hectorite, and swellable mica having sodium ions between layers are preferable in terms of availability, dispersibility, and an effect of improving physical properties.

From the viewpoint of the affinity with the polyester resin and the dispersibility in the resin, a silane-based compound is added to the swellable silicate which is swollen in a solvent as inorganic particles which can be particularly preferably used in the present invention. Silane clay complexes prepared by introduction.

As the above-mentioned silane-based compound, any compound generally used can be used, and is a compound represented by the following general formula (1) Y _n SiX _4-n (1). N in the general formula (1) is an integer of 0 to 3, and Y is a group having 1 carbon atom which may have a substituent.
~ 25 hydrocarbon groups. Examples of the substituent when the hydrocarbon group having 1 to 25 carbon atoms has a substituent include, for example, a group bonded by an ester bond, a group bonded by an ether bond, an epoxy group, an amino group, and a carboxyl group. Group, a group having a carbonyl group at a terminal, an amide group, a mercapto group, a group bonded by a sulfonyl bond, a group bonded by a sulfinyl bond, a nitro group, a nitroso group, a nitrile group, a halogen atom and a hydroxyl group. Can be
The hydrocarbon group may be substituted with one kind of these substituents or two or more kinds. X is a hydrolyzable group and / or a hydroxyl group. Examples of the hydrolyzable group include an alkoxy group, an alkenyloxy group,
Examples include a ketoxime group, an acyloxy group, an amino group, an aminoxy group, an amide group, and a halogen atom. In the general formula (1), when n or 4-n is 2 or more, n Y or 4-n X may be the same or different.

As used herein, the term "hydrocarbon group" refers to a linear or branched (ie, having a side chain) saturated or unsaturated monovalent or polyvalent aliphatic hydrocarbon group or aromatic hydrocarbon group. It means a hydrogen group and an alicyclic hydrocarbon group, and examples thereof include an alkyl group, an alkenyl group, an alkynyl group, a phenyl group, a naphthyl group, and a cycloalkyl group. In the present specification, the “alkyl group” is intended to include a polyvalent hydrocarbon group such as an “alkylene group” unless otherwise specified. Similarly, the alkenyl, alkynyl, phenyl, naphthyl, and cycloalkyl groups include alkenylene, alkynylene, phenylene, naphthylene, cycloalkylene, and the like, respectively.

In the above general formula (1), Y represents 1 carbon atom.
Examples of the silane compound in the case of a hydrocarbon group of from 25 to 25 include a compound having a linear long-chain alkyl group such as decyltrimethoxysilane, a compound having a lower alkyl group such as methyltrimethoxysilane, and 2 Those having an unsaturated hydrocarbon group such as hexenyltrimethoxysilane, those having an alkyl group having a side chain such as 2-ethylhexyltrimethoxysilane, those having a phenyl group such as phenyltriethoxysilane, 3 -Β-
Examples include those having a naphthyl group such as naphthylpropyltrimethoxysilane, and those having an aralkyl group such as p-vinylbenzyltrimethoxysilane. Examples of the silane compound when Y is a vinyl group among hydrocarbon groups having 1 to 25 carbon atoms include vinyltrimethoxysilane, vinyltrichlorosilane, and vinyltriacetoxysilane. When Y is a hydrocarbon group substituted by a group bonded by an ester bond, examples of the silane compound include γ-methacryloxypropyltrimethoxysilane. Examples of the silane-based compound when Y is a hydrocarbon group substituted with a group linked by an ether bond include γ-polyoxyethylenepropyltrimethoxysilane and 2-ethoxyethyltrimethoxysilane. Can be
When Y is a hydrocarbon group substituted with an epoxy group, examples of the silane-based compound include γ-glycidoxypropyltrimethoxysilane. Examples of the silane compound when Y is a hydrocarbon group substituted with an amino group include γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, and γ-aniline. Linopropyltrimethoxysilane. When Y is a hydrocarbon group substituted with a group having a terminal carbonyl group, examples of the silane-based compound include γ-ureidopropyltriethoxysilane. When Y is a hydrocarbon group substituted with a mercapto group, examples of the silane-based compound include γ-mercaptopropyltrimethoxysilane. When Y is a hydrocarbon group substituted with a halogen atom, examples of the silane-based compound include γ-chloropropyltriethoxysilane. When Y is a hydrocarbon group substituted with a group bonded by a sulfonyl bond, examples of the silane-based compound include γ-phenylsulfonylpropyltrimethoxysilane. When Y is a hydrocarbon group substituted with a group bonded by a sulfinyl bond, examples of the silane compound include γ-phenylsulfinylpropyltrimethoxysilane. Examples of the silane-based compound when Y is a hydrocarbon group substituted with a nitro group include γ
-Nitropropyltriethoxysilane. Y
Is a hydrocarbon group substituted with a nitroso group, examples of the silane-based compound include γ-nitrosopropyltriethoxysilane. When Y is a hydrocarbon group substituted with a nitrile group, examples of the silane-based compound include γ-cyanoethyltriethoxysilane and γ-cyanopropyltriethoxysilane.
When Y is a hydrocarbon group substituted with a carboxyl group, examples of the silane-based compound include γ- (4-carboxyphenyl) propyltrimethoxysilane. In addition to the above, silane compounds in which Y is a hydrocarbon group having a hydroxyl group can also be used. Such an example includes N, N-di (2-hydroxyethyl) amino-3-
Propyltriethoxysilane. Hydroxyl groups can also be in the form of silanol groups (SiOH). Substitutes or derivatives of the above silane compounds may also be used. These silane compounds can be used alone or in combination of two or more.

The method for preparing the above-mentioned inorganic particle-water dispersion is not particularly limited, and may be carried out using, for example, a conventionally known wet stirrer. As the wet stirrer, a high-speed stirrer in which stirring blades rotate at high speed and stir, a wet mill for wet-milling a sample in a gap between a rotor and a stator under high shearing speed, and a hard medium were used. Examples include mechanical wet pulverizers and wet collision pulverizers that collide a sample at a high speed with a jet nozzle or the like. In order to perform the mixing efficiently, the rotation speed of the stirring is preferably 500 rpm
m or a shear rate of 300 (1 / s) or more. Preferably, the upper limit of the number of revolutions is 2500
0 rpm, and the upper limit of the shear rate is preferably 50 rpm.
0000 (1 / s). Even if the stirring is performed at a value larger than these upper limits, the mixing effect does not tend to be further improved. Therefore, it is not necessary to perform the stirring at a value larger than the upper limit.

In the inorganic particle-water dispersion, if it does not cause deterioration of the thermoplastic polyester resin,
If necessary, a polar solvent compatible with water at any ratio may be contained. Examples of the polar solvent include, for example, alcohols such as methanol, ethanol, and isopropanol;
Ethylene glycol, propylene glycol, 1,4-
Examples include glycols such as butanediol, ketones such as acetone and methyl ethyl ketone, ethers such as diethyl ether and tetrahydrofuran, amide compounds such as dimethylformamide, and other solvents such as dimethyl sulfoxide and 2-pyrrolidone. These polar solvents may be used alone or in combination of two or more.

When a silane clay composite is used as the inorganic particles, the preparation of the inorganic particle-water dispersion containing the silane clay composite and water is performed in water or a mixed solvent of water and the above-mentioned polar solvent. The swellable silicate can be formed by expanding the bottom interval of the swellable silicate to a swollen state, and then mixing the above-mentioned silane compound. The method of mixing is not particularly limited, and is performed using, for example, a conventionally known wet stirrer as described above.

The introduction of the silane-based compound into the swellable silicate which is in a swollen state due to an increase in the distance between the bottom surfaces is performed by combining the hydroxyl group present on the surface of the swellable silicate with the hydrolyzable group of the silane-based compound. (Or) by reacting with a hydroxyl group.

When the silane compound introduced into the swellable silicate further has a reactive group such as a hydroxyl group, a carboxyl group, an amino group, an epoxy group or a vinyl group, It is also possible to further add a compound capable of reacting with such a reactive group and react the compound with the reactive group. In this way,
The length of the functional group chain of the silane compound introduced into the swellable silicate and the polarity can be changed. In this case, as the compound to be added, the above-mentioned silane-based compound itself can be used, but is not limited thereto, and any compound can be used depending on the purpose.
Examples include an epoxy group-containing compound, an amino group-containing compound, a carboxyl group-containing compound, an acid anhydride group-containing compound, and a hydroxyl group-containing compound.

The above reaction proceeds sufficiently at room temperature, but may be heated if necessary. The maximum temperature during heating can be arbitrarily set as long as it is lower than the decomposition temperature of the silane compound used and lower than the boiling point of the dispersion medium.

The amount of the silane compound used depends on the dispersibility of the silane clay composite in the inorganic particle-water dispersion, the affinity between the silane clay composite and the thermoplastic polyester resin, and the amount of the silane compound in the polyester resin composition. It can be adjusted so that the dispersibility of the silane clay composite is sufficiently enhanced. If necessary, a plurality of silane compounds having different functional groups may be used in combination. Therefore, the addition amount of the silane-based compound is not necessarily limited to a numerical value, but the swellable silicate 100
Parts by weight, preferably 0.1 to 200 parts by weight, more preferably 0.2 to 180 parts by weight,
Even more preferably 0.3 to 160 parts by weight,
Particularly preferred is 0.4 to 140 parts by weight, most preferred 0.5 to 120 parts by weight. If the amount of the silane compound is too small, the effect of finely dispersing the obtained silane clay composite tends to be insufficient. Further, even if it is added more than necessary, the effect of finely dispersing is not further improved, so it is not necessary to add more than necessary.

The spacing between the bottom surfaces of the silane clay composite obtained as described above can be enlarged compared to the initial spacing between the bottom surfaces of the swellable silicate due to the presence of the introduced silane compound. For example, a swellable silicate dispersed in a dispersion medium and having an increased bottom surface interval, when the silane-based compound is not introduced, when the dispersion medium is removed, the layers return to a state in which the layers are aggregated again. For example, by introducing the silane compound after expanding the bottom surface interval, even after removing the dispersion medium, the obtained silane clay composite can exist in a state where the bottom surface interval is expanded without the layers being aggregated. . The distance between the bottom surfaces of the silane clay composite is preferably at least 1.3 times, more preferably at least 1.5 times, still more preferably at least 1.7 times, as compared with the initial distance between the bottom surfaces of the swellable silicate. Particularly preferably, the magnification is at least twice. As described above, the affinity between the silane clay composite and the resin can be increased by introducing the silane-based compound and by increasing the distance between the bottom surfaces.

The introduction of the silane compound into the swellable silicate can be confirmed by various methods. As a method for confirmation, for example, the following method can be mentioned.

First, by simply washing the silane clay complex using an organic solvent such as tetrahydrofuran or chloroform, the adsorbed silane compound is simply washed and removed. After washing the silane clay complex into powder in a mortar or the like, it is sufficiently dried. Next, this silane clay composite is sufficiently mixed with a window material such as powdered potassium bromide (KBr) at a predetermined ratio to form a pressurized tablet, and a transmission method using Fourier transform (FT) -IR. The absorption band derived from the silane compound is measured by the method described above. When more accurate measurement is desired, or when the amount of the introduced silane compound is small, a sufficiently dried powdery silane clay composite is directly subjected to a diffuse reflection method (DRIFT).
It is desirable to measure with.

It can be confirmed by various methods that the distance between the bottom surfaces of the silane clay composite is larger than that of the swellable silicate. As a method for confirmation, for example, the following method can be mentioned.

That is, in the same manner as described above, the adsorbed silane-based compound is simply removed from the silane-clay composite by washing with an organic solvent, and after drying, the small-angle X-ray diffraction method (S
AXS). In this method, the X-ray diffraction peak angle value derived from the (001) plane of the powdery silane clay composite is measured by SAXS, and the angle is applied to Bragg's formula to calculate the bottom surface interval. Similarly, by measuring the base spacing of the initial swellable silicate and comparing the two, the expansion of the base spacing can be confirmed.

After washing with an organic solvent as described above,
The absorption band derived from the added silane compound is determined by FT-IR
By measuring with SAXS or the like that the distance between the bottom surfaces is larger than the swellable silicate of the raw material, it can be seen that a silane clay complex has been formed.

It is necessary that the concentration of the inorganic particles contained in the aqueous dispersion of inorganic particles used in the present invention is higher than the concentration of the inorganic particles when the inorganic particle-water dispersion exhibits a liquid limit. is there.

Here, “liquid limit” in the present specification means, for example, those defined in JISA1205. That is, a sample obtained by sufficiently mixing inorganic particles and water was placed in a measuring dish such as a brass dish, and the dish containing the sample was dropped 25 times twice a second from a height of 1 cm. Occasionally, it refers to the water content when a portion of a sample divided by a groove tool flows out from both sides of the groove and joins over a length of about 1.5 cm. Therefore, the concentration at which the liquid property limit is indicated means the content of inorganic particles contained in the sample at that time.

The concentration of the inorganic particles when the inorganic particle-water dispersion exhibits a liquid limit varies depending on the type, form, particle size, etc. of the inorganic particles used. For example, when swellable silicate such as smectite clay or swellable mica is used as the inorganic particles, the concentration depends on the swellability, cation exchange capacity, length of one side of the layer, etc. Although not limited, for example, it is approximately 5 to 8% by weight. Further, when a silane clay composite is used as the inorganic particles, the concentration thereof depends on the treatment amount and type of the silane-based compound, and thus is not specified unconditionally. For example, when Y in the above general formula (1) is an amino group About 5 to 8 when the hydrocarbon group is substituted with
% By weight, and when Y is a hydrocarbon group substituted with a group linked by an ether bond, it is approximately 7 to 12%.
% By weight, and when Y is a hydrocarbon group substituted by a group bonded by an ester bond, a hydrocarbon group substituted by an epoxy group, or a hydrocarbon group substituted by a phenyl group, 10 to 15% by weight,
It is not limited to these.

If the concentration of the inorganic particles in the aqueous dispersion of inorganic particles is higher than the concentration of the inorganic particles at the time of exhibiting the liquid limit, the inorganic particles in the aqueous dispersion of inorganic particles do not settle and separate. By kneading with the resin, the inorganic particles can be easily and finely dispersed in the resin.

On the other hand, when the concentration of the inorganic particles in the inorganic particle-water dispersion is lower than the concentration of the inorganic particles at the time when the liquidity limit is exhibited, the dispersion becomes a slurry, that is, a fluid.
In such cases, the inorganic particles in the dispersion settle easily,
They tend to separate. Even if a slurry in which the inorganic particles are precipitated and separated is added to and kneaded with the resin, the inorganic particles may not be uniformly dispersed in the resin. Further, in order to prevent sedimentation / separation, it may be necessary to stir until just before kneading with the resin, which complicates the manufacturing apparatus.

The upper limit of the concentration of the inorganic particles in the inorganic particle-water dispersion is not particularly limited, but is preferably 90% by weight.
, More preferably 80% by weight, and even more preferably 70% by weight. If it is too high, the dispersibility of the inorganic particles in the polyester composition may be impaired.

In the present invention, water is used to disperse the inorganic particles. When water is not used, there is a disadvantage that the dispersibility of the inorganic particles in the polyester composition is impaired.

In the present invention, kneading of the thermoplastic polyester resin and the inorganic particle-water dispersion can be carried out by a commonly used known melt kneading machine. Examples of such a melt kneader include kneaders capable of giving a high shearing force to the system, such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, and a roll. In particular, a meshing twin-screw extruder having a kneading disk portion and a deaeration port is preferable, and the deaeration port can be maintained under reduced pressure to remove water and the like.

As described above, according to the method for producing the polyester resin composition of the present invention, the inorganic particles do not settle or separate before kneading, and the inorganic particles are uniformly dispersed in the thermoplastic polyester resin by a simple method of kneading. It can be finely dispersed. This makes it possible to easily produce a polyester resin composition excellent in various physical properties such as mechanical properties, heat resistance, dimensional stability, and surface appearance.

The dispersion state of the inorganic particles in the polyester resin composition obtained by the production method of the present invention includes, for example, the equivalent area circle diameter [D], the number of dispersed particles [N], the aspect ratio (layer length) described below. / Layer thickness ratio), average layer thickness or maximum layer thickness.

First, the equivalent area circle diameter [D] is defined as the diameter of a circle having an area equal to the area on this image of individual inorganic particles dispersed in various shapes in an image obtained by a microscope or the like. Defined to be. In that case, among the inorganic particles dispersed in the polyester resin composition, the equivalent area circle diameter [D]
Is preferably not less than 20%, more preferably not less than 35%, still more preferably not less than 50%, particularly preferably not less than 65%. Further, the average value of the equivalent area circle diameter [D] of the inorganic particles in the polyester resin composition is preferably 5000 ° or less, more preferably 450 ° or less.
0 ° or less, more preferably 4000 ° or less, particularly preferably 3500 ° or less. Although there is no particular lower limit, it is preferably about 100 °.

In the measurement of the equivalent area circle diameter [D], an arbitrary region containing 100 or more inorganic particles is selected on an image photographed using a microscope or the like, and imaged using an image processing device or the like. It can be quantified by computer processing.

The value [N] of the number of dispersed particles is defined as the number obtained by dividing the number of particles present in an area of 100 μm ² of the resin composition by a, where a is derived from the above-mentioned layered silicate. The [N] value of the inorganic particles in the polyester resin composition, which is a numerical value when the ash ratio of the resin composition to be expressed by weight%,
It is preferably 30 or more, more preferably 40 or more, still more preferably 50 or more, and particularly preferably 60 or more. There is no particular upper limit, but preferably 1
It is about 000. The [N] value can be obtained, for example, as follows. That is, the polyester resin composition is cut into an ultra-thin section having a thickness of about 50 μm to 100 μm, and on a picture taken with a transmission electron microscope (TEM) or the like, inorganic particles existing in an arbitrary area having an area of 100 μm ² are obtained. Can be determined by dividing the number of particles by the weight ratio of the inorganic particles used. Alternatively, on a TEM image, 100
Select an arbitrary area (area is measured beforehand) in which more than one particle is present, divide the number of particles present in this area by the weight ratio of the inorganic particles used, and convert the value into an area of 100 μm ^2. [N] value may be used. Therefore, the [N] value is determined by the TE value of the polyester resin composition obtained by the production method of the present invention.
It can be quantified by using an M photograph or the like.

Here, the ash ratio refers to a weight ratio of inorganic particles remaining when the polyester resin composition is heated and ashed at about 620 ° C. to the resin, for example, JIS K
It is measured according to 7052.

When a swellable silicate or a silane clay composite is used as the inorganic particles, the dispersion state of the inorganic particles in the polyester resin composition depends on the average aspect ratio, the average layer thickness, or the maximum layer thickness. Can be represented.

The average aspect ratio is defined as the average value of the ratio of the layer length / layer thickness of the swellable silicate or silane clay composite dispersed in the polyester resin composition. The average aspect ratio is preferably 10 to 300, more preferably 15 to 300, and still more preferably 2 to 300.
0 to 300. There is no particular upper limit for the average aspect ratio, but it is preferably about 300.

The average layer thickness is defined as the average value of the layer thickness of the swellable silicate or silane clay composite dispersed in a thin plate shape. The upper limit of the average layer thickness is preferably 5
00 ° or less, more preferably 450 ° or less, and even more preferably 400 ° or less. The lower limit of the average layer thickness is not particularly limited, but is preferably about 10 °.

Further, the maximum layer thickness is defined as the maximum value of the layer thickness of the swellable silicate or silane clay composite dispersed in a thin plate shape in the polyester resin composition. The upper limit of the maximum layer thickness is preferably 2000 ° or less, more preferably 1800 ° or less, and even more preferably 1500 ° or less. The lower limit of the maximum layer thickness is not particularly limited, but is preferably about 10 °.

The layer thickness and the layer length were determined by heating and melting the polyester resin composition obtained by the production method of the present invention.
A film obtained by hot press molding or stretch molding,
In addition, a thin molded product or the like obtained by injection molding of a molten resin can be obtained from an image photographed using a microscope or the like.

That is, first, a test piece of a film prepared by the above-described method or a thin flat injection-molded product having a thickness of about 0.5 to 2 mm is placed. Then
Approximately 50 μm to 100 μm in a direction perpendicular to the surface direction of the test piece.
A layer thickness and a layer length can be determined by cutting out an ultrathin section having a thickness of μm and observing the section at a high magnification of about 4 to 100,000 or more using a transmission electron microscope or the like. Measurement, on the image of the transmission electron microscope obtained by the above method, select any area containing 100 or more swellable silicate or silane clay complex, image with an image processing device and the like, It can be quantified by computer processing. Alternatively, it can also be obtained by measuring using a ruler or the like.

The polyester resin composition obtained from the production method of the present invention may contain, if necessary, polybutadiene, butadiene-styrene copolymer, acrylic rubber, ionomer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer. Polymers, natural rubber, chlorinated butyl rubber, homopolymers of α-olefins, and copolymers of two or more α-olefins (including any copolymers such as random, block, and graft, and mixtures thereof) Or an impact modifier such as an olefin-based elastomer. These modifiers may be modified with an acid compound such as maleic anhydride or an epoxy compound such as glycidyl methacrylate.

Further, the polyester resin composition includes:
Within a range that does not impair properties such as mechanical properties and moldability, 1
Any other thermoplastic or thermosetting resin, such as unsaturated polyester resin, polyester carbonate resin, liquid crystal polyester resin, polyolefin resin, polyamide resin, rubbery polymer reinforced styrene resin, polyphenylene sulfide resin, A polyphenylene ether resin, a polyacetal resin, a polysulfone resin, a polyarylate resin, or the like may be added.

Further, depending on the purpose, the polyester resin composition may contain a pigment or a dye, a heat stabilizer, an antioxidant,
Additives such as ultraviolet absorbers, light stabilizers, lubricants, plasticizers, flame retardants, and antistatic agents can be added. The polyester resin composition obtained in the present invention may be molded by injection molding, hot press molding, or the like, and can also be used for blow molding. The resulting molded article is excellent in appearance, excellent in mechanical properties, heat-resistant deformation properties, etc., and is therefore suitably used, for example, in automobile parts, household electric parts, household daily necessities, packaging materials, and other general industrial materials.

[0077]

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

The main raw materials used in the following Examples and Comparative Examples are summarized below. Unless otherwise specified, the raw materials were not purified.

(Raw materials) Polyethylene terephthalate: PBK manufactured by Kanebo Co., Ltd.
2. Logarithmic viscosity (η _inh ) = 0.63 (dl / g) (hereinafter referred to as PET) was used. -Inorganic particles: Swellable silicate, Wenger HVP (Bentonite, bottom surface interval = 13 °, hereinafter referred to as Wenger HVP) from Toyshun Yoko Co., Ltd. was used. -Γ- (2-aminoethyl) aminopropyltrimethoxysilane: A-1120 of Nippon Unicar Co., Ltd. (hereinafter A1
120). Γ- (polyoxyethylene) propyltrimethoxysilane: A-1230 of Nippon Unicar Co., Ltd. (hereinafter A1
230).

The evaluation methods in the following examples and comparative examples are summarized below.

(Liquidity Limit) The measurement of the liquidity limit of the inorganic particle-water dispersion was performed according to JISA1205. That is, the inorganic particle-water dispersion was placed in a sample dish of a liquid property limiter, stabilized for 1 hour while preventing evaporation, and then the sample was divided into two minutes with a squeezing jig. Next, the sample dish was dropped 25 times at a rate of 2 times per second from a height of 1 cm, and the time when the sample of the divided portion merged over 1.5 cm was defined as the liquid limit, and the content of inorganic particles at that time was determined. It was the concentration of the inorganic particles at the liquid limit.

(Measurement of Dispersion State) The dispersion state of the inorganic particles in the polyester resin composition was determined by measuring the thickness of a test piece obtained by molding this composition from 50 to 100.
The measurement was performed using an ultra-thin section of μm. Using a transmission electron microscope (TEM; JEOL JEM-1200EX), the dispersion state of the inorganic particles was observed and photographed at an acceleration voltage of 80 kV and a magnification of 40,000 to 1,000,000 times. In a TEM photograph, an arbitrary region where 100 or more dispersed particles are present is selected, and the number of particles ([N] value) and the equivalent area circle diameter [D] are manually measured using a graduated ruler or interquest. The measurement was performed by processing using an image analysis device PIASIII manufactured by the company. In particular, regarding the measurement of the [N] value, first, the number of inorganic particles present in the selected region was determined on the TEM image. Separately, the ash content of the resin composition derived from the inorganic particles was measured. For example, if the ash content is a wt%,
The value obtained by dividing the number of particles by a and converting it to an area of 100 μm ² was defined as an [N] value.

When the size of the dispersed particles is large and observation with a TEM is inappropriate, the [N] value is obtained by an optical microscope (optical microscope BH-2 manufactured by Olympus Optical Co., Ltd.) in the same manner as described above. Was. However, if necessary, the sample was melted at 250 to 290 ° C. using a hot stage THM600 manufactured by LINKAM, and the state of the dispersed particles was measured in the molten state.

The average aspect ratio was a number average value of the ratio between the layer length and the layer thickness of each layered silicate.

The [N] value was measured as follows. First, on the TEM image, the number of layered silicate particles present in the selected region was determined. Separately, the ash content of the resin composition derived from the layered silicate was measured. The value obtained by dividing the number of particles by the ash content and converting the result to an area of 100 μm ² was defined as the [N] value.

The average layer thickness was the number average of the layer thicknesses of the individual layered silicates, and the maximum layer thickness was the maximum value among the layer thicknesses of the individual layered silicates.

The aspect ratio of the dispersed particles which are not dispersed in a thin plate shape was a value of major axis / minor axis. Here, the long diameter is assumed to be a rectangle having the smallest area among the rectangles circumscribing the target particle in a microscope image or the like, and the long side of the rectangle is intended. In addition, the minor axis is intended to be the short side of the rectangle having the minimum area.

(FT-IR) Silane clay composite 1.0 g
Is added to 50 ml of tetrahydrofuran (THF), and 2
After stirring for 4 hours to wash and remove the adsorbed silane compound, the mixture was centrifuged to separate the supernatant. This washing operation was repeated three times. After washing, about 1 mg of the sufficiently dried silane clay complex and about 200 mg of KBr powder were sufficiently mixed using a mortar, and a KBr disk for measurement was prepared using a tabletop press. Next, FT-IR was measured by a transmission method using an infrared spectrometer (manufactured by Shimadzu Corporation, 8100M) to confirm an absorption band derived from the silane compound. M detector cooled with liquid nitrogen
Using a CT detector, the resolution was 4 cm ^-1 and the number of scans was 100.

(Measurement of Bottom Spacing by Small-Angle X-Ray Diffraction Method (SAXS)) X-ray Generator (RU-R, manufactured by Rigaku Corporation)
200B), target CuKα ray, Ni filter, voltage 40 kV, current 200 mA, scanning angle 2θ =
Under the measurement conditions of 0.2 to 16.0 ° and a step angle of 0.02 °, the bottom interval of the silane clay composite was measured. The distance between the bottom surfaces was calculated by substituting the small-angle X-ray diffraction peak angle value into the Bragg equation.

(Mechanical Properties) The polyester resin composition obtained by the production method of the present invention is dried (140 ° C., 5 hours).
did. Injection molding machine with a mold clamping pressure of 75t (manufactured by Toshiba Machine Co., Ltd.
Using IS-75E), injection molding was performed under the conditions of a resin temperature of 250 to 280 ° C., a gauge pressure of about 10 MPa, and an injection speed of about 50% to produce a test piece having a size of about 10 × 100 × 6 mm. The flexural strength and flexural modulus of the obtained test piece were determined by A
Measured according to STMD-790. The larger the values of the flexural strength and the flexural modulus, the more preferable.

(Surface properties) Using the test piece prepared in the above (mechanical properties), a surface roughness meter "surf" manufactured by Tokyo Seimitsu Co., Ltd. was used.
The center line roughness was measured using a COM1500A. The smaller the value is, the smoother the surface is, which is preferable.

(Ash content) The ash content of the polyester resin composition derived from the inorganic particles was measured according to JIS K7052.

(Evaluation Example 1) Deionized water, Wenger HV
By stirring and mixing P and A1120 (4.2 parts by weight based on Wengel HVP), an inorganic particle-water dispersion was obtained. The liquid property limit of the obtained inorganic particle-water dispersion was measured by the above method. The concentration of the inorganic particles at the liquid property limit of the inorganic particle-water dispersion was about 6% by weight.

(Evaluation Example 2) Deionized water, Wenger HV
By stirring and mixing P and A1230 (10 parts by weight based on Wengel HVP), an inorganic particle-water dispersion was obtained. The liquid property limit of the obtained inorganic particle-water dispersion was measured by the above method. The concentration of the inorganic particles at the liquid property limit of the inorganic particle-water dispersion was about 13% by weight.

Table 1 summarizes Evaluation Examples 1 and 2.

[0096]

[Table 1]

(Example 1) 2100 g of ion-exchanged water,
180 g of Wengel HVP (inorganic particles) and 7.5 g
A1120 was stirred and mixed for 90 minutes. Then, by heating to remove 900 g of water, a silane clay composite (inorganic particle-water dispersion) containing about 13% by weight of inorganic particles was obtained. The confirmation of the silane clay composite was performed by measuring the distance between the bottom surfaces and the absorption band of the functional group derived from the silane compound by the above method. Less than,
In Examples 2 to 4, similarly, the obtained silane clay composite was confirmed. Table 2 shows the results.

Next, the obtained inorganic particle-water dispersion was added to 4
It was left for 8 hours. After standing, the inorganic particles did not settle or separate at all. Twin screw extruder (Nippon Steel Corporation, LABO
TEX30), the above-mentioned inorganic particle-water dispersion, 25
00 g PET resin, 5.0 g hindered phenol-based stabilizer (Adeka Stab AO60 from Asahi Denka Co., Ltd.
O60) was melt-kneaded under the conditions of a set temperature of 260 to 280 ° C. and a rotation speed of 100 rpm to obtain a polyester resin composition. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.

(Example 2) 2100 g of ion-exchanged water,
180 g of Wengel HVP and 7.5 g of A1120
Was stirred for 90 minutes to obtain an inorganic particle-water dispersion containing about 7.9% by weight of inorganic particles. The obtained inorganic particle-water dispersion was allowed to stand for 48 hours, but the inorganic particles did not settle or separate at all. This inorganic particle-water dispersion and the PET resin were melt-kneaded in the same manner as in Example 1 to obtain a polyester resin composition. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.
Shown in

(Example 3) 2100 g of ion-exchanged water,
180 g of Wengel HVP and 18 g of A1230
Was stirred and mixed for 60 minutes. Then, heat to 1600
g of water to remove about 26.5 inorganic particles.
An inorganic particle-water dispersion containing about 10% by weight was obtained. The obtained inorganic particle-water dispersion was allowed to stand for 48 hours, but the inorganic particles did not settle or separate at all. The inorganic particles-water dispersion and the PET resin were melt-kneaded in the same manner as in Example 1,
A polyester resin composition was obtained. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.

(Example 4) 2100 g of ion-exchanged water,
180 g of Wengel HVP and 18 g of A1230
Was stirred for about 60 minutes. Then heat to 1200g
By removing water, an inorganic particle-water dispersion containing about 16.7% by weight of inorganic particles was obtained. The obtained inorganic particle-water dispersion was allowed to stand for 48 hours, but the inorganic particles did not settle or separate at all. This inorganic particle-water dispersion and the PET resin were melt-kneaded in the same manner as in Example 1 to obtain a polyester resin composition. Table 3 shows the composition of this composition.
Shown in This composition was evaluated according to the method described above. Table 4 shows the results.

Comparative Example 1 5000 g of ion-exchanged water
180 g of Wengel HVP and 7.5 g of A1230
Is stirred for 90 minutes to reduce the inorganic particles to about 3.
An aqueous dispersion of inorganic particles containing 5% by weight was obtained. When the obtained inorganic particle-water dispersion was allowed to stand for 48 hours, the inorganic particles settled and separated. This inorganic particle-water dispersion and the PET resin were melt-kneaded in the same manner as in Example 1 to obtain a polyester resin composition. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.
Shown in

Comparative Example 2 2500 g of ion-exchanged water
180 g of Wengel HVP and 18 g of A1230
Was stirred for about 60 minutes to obtain an inorganic particle-water dispersion containing about 6.7% by weight of inorganic particles. When the obtained inorganic particle-water dispersion was allowed to stand for 48 hours, the inorganic particles settled and separated. This inorganic particle-water dispersion and PET
The resin was melt-kneaded in the same manner as in Example 1 to obtain a polyester resin composition. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.

Comparative Example 3 2500 g of PET resin and 5
g of AO60 was kneaded in the same manner as in Example 1 to obtain a polyester resin composition. Table 3 shows the composition of this composition. This composition was evaluated according to the method described above. Table 4 shows the results.

[0105]

[Table 2]

[0106]

[Table 3]

[0107]

[Table 4]

As can be seen from Tables 2 to 4, in Examples 1 to 4, the dispersion in which the inorganic particles were not settled or separated was added and kneaded with the polyester resin. Therefore, the inorganic particles were uniformly finely dispersed in the polyester resin. It can be seen that an excellent property improving effect was obtained. In Comparative Examples 1 and 2, the dispersion in which the inorganic particles were settled and separated was added and kneaded with the polyester resin. Therefore, in the obtained polyester resin composition, there were many portions where the inorganic particles were not uniformly dispersed, and the physical properties were improved. It can be seen that the effect of is small.

[0109]

As described in detail above, according to the present invention,
Inorganic particles containing inorganic particles and water-by increasing the concentration of the inorganic particles in the aqueous dispersion, higher than the concentration when showing the liquidity limit, to suppress the fluidity of the inorganic particles-aqueous dispersion. Sedimentation and separation of inorganic particles can be prevented. Thereby, the inorganic particles can be uniformly and finely dispersed in the polyester resin by a simple method such as melt-kneading, and a polyester resin composition having an excellent balance of physical properties such as mechanical properties and heat resistance can be produced.

Claims (3)

[Claims] 1. A method for producing a polyester resin composition containing a thermoplastic polyester resin and inorganic particles, comprising a step of kneading a thermoplastic polyester resin and a mixture containing inorganic particles and water. Wherein the concentration of the inorganic particles in the mixture is higher than the concentration at which the mixture exhibits a liquid property limit. 2. The swellable silicate in which the inorganic particles are swollen in a solvent has the following general formula (1): Y _n SiX _4-n (1) (where n is an integer of 0 to 3) Y is a hydrocarbon group having 1 to 25 carbon atoms which may have a substituent;
Is a hydrolyzable group and / or a hydroxyl group; n Y and 4-n X may be the same or different.
The method according to claim 1, which is a silane clay composite prepared by introducing a silane compound represented by the following formula: 3. A polyester resin composition containing a thermoplastic polyester resin and inorganic particles, obtained by the method according to claim 1 or 2.