JP2007290943A - Method for producing modified alumina particle-dispersed sol, method for producing modified alumina particles and thermoplastic resin composition using the sol, and modified alumina particle-dispersed sol, modified alumina particles, and thermoplastic resin composition obtained thereby - Google Patents

Abstract

An object of the present invention is to provide an alumina particle that can be used as a filler for a thermoplastic resin, and to provide a thermoplastic resin composition having improved properties such as strength, elastic modulus, and heat resistance.
When the alumina particles are brought into contact with an organic compound to modify and modify the alumina particles, the alumina particles and the organic compound are contacted at a temperature range of 100 to 400 ° C. As a result, the surface active groups of the alumina particles are sufficiently deactivated, and when blended in a predetermined thermoplastic resin, the effect as a filler is exhibited, and various properties such as strength, elastic modulus, and heat resistance are exhibited. Can improve the thermoplastic resin composition.
[Selection figure] None

Description

  The present invention relates to a method for producing a modified alumina particle-dispersed sol, a method for producing a modified alumina particle and a thermoplastic resin composition using the sol, and a modified alumina particle-dispersed sol, a modified alumina particle, and a thermoplastic resin composition obtained thereby. Related to things.

  Silica and other metal oxide fine particles have recently been recognized for their usefulness and applicability in various industrial fields, but they have a large amount of hydroxyl groups on the surface to form a hydrophilic active surface. There are many. On the other hand, the smaller the particle size, the larger the surface area, and the stronger the interaction, the more likely aggregation occurs. It is not easy to uniformly disperse these as nanoparticles in an organic solvent or resin.

  In order to achieve uniform dispersion of fine metal oxide fine particles corresponding to the above-mentioned nanoparticles in an organic substance, the surface of the metal oxide fine particles is provided with a functional group capable of uniformly dispersing the target compound. It is effective to chemically treat the surface with an organic compound to make it hydrophobic. Thereby, it becomes difficult for fine particles to aggregate and the dispersibility in an organic compound can be improved.

  On the other hand, as a technique to improve various physical properties of organic resins, while maintaining the flexibility, low density and moldability that are the characteristics of organic polymers, the high strength, high elastic modulus, heat resistance, which are the characteristics of inorganic compounds, The development of materials that have both electrical properties has been actively carried out, and composite materials that use metal oxide fine particles as described above in place of conventional glass fiber and reinforced resin such as talc as a method for improving physical properties. A resin composition called a so-called polymer nanocomposite has attracted attention. Examples of such composite materials include “composite materials and manufacturing methods thereof (Patent No. 2519045 / Toyota Chuken)” and “polyamide composite materials and manufacturing methods thereof (Japanese Patent Publication No. 7-47644 / Ube Industries, etc.)”, “Polyolefin-based composite material and production method thereof (Japanese Patent Laid-Open No. 10-30039 / Showa Denko)” and the like.

  Conventionally, metal oxide fine particles such as silicon dioxide, titanium dioxide, and aluminum oxide have been widely used as fillers for thermoplastic resins. In applying inorganic fine particles to this application, if the above-mentioned aggregation can be suppressed, it is preferable that the particle size of the inorganic fine particles is small, and the surface area increases as the particle size is reduced. It is expected to develop characteristics that were not found in

  Among the inorganic fine particles, alumina particles are generally present as coarse micron-order particles, and are used by being pulverized or the like. However, in recent years, nano-order levels can also be synthesized. An example is the ultrafine alumina “AEROXIDE® Alu C” manufactured by Degussa.

Patent No. 2519045 JP 7-47644 Japanese Patent Laid-Open No. 10-30039

  However, when alumina particles are mixed with an organic resin such as a thermoplastic resin, the molecular weight of the thermoplastic resin decreases, and this is accompanied by an appearance and flexibility that should be maintained as a bulk composition or coating film. There is a drawback that the physical properties of the polymer are greatly impaired, such as loss of impact resistance.

  TECHNICAL FIELD The present invention relates to a method for producing a modified alumina particle-dispersed sol that provides alumina particles that can be used as a filler for thermoplastic resins, and has improved properties such as strength, elastic modulus, and heat resistance. An object is to provide a composition.

In order to achieve the above object, the present invention provides:
When the alumina particles are brought into contact with a modifying agent composed of an organic compound or an inorganic compound to modify and modify the alumina particles, the contact between the alumina particles and the modifying agent is performed in a temperature range of 100 to 400 ° C. The present invention relates to a method for producing a modified alumina particle-dispersed sol.

  The present inventors have intensively studied to solve the above problems. As a result, the surface of the alumina particles contains chemically active groups represented by AlOH groups and water (adsorbed water) drawn by the interaction between the active groups. When the alumina particles are blended as a filler, the active groups and adsorbed water attack the relatively weak parts contained in the thermoplastic resin to cause hydrolysis and oxidative degradation. It was. As a result, the molecular weight of the thermoplastic resin is reduced, and various properties such as strength and elastic modulus reduction of the obtained thermoplastic resin composition are deteriorated, and the thermoplastic resin composition is colored. I found a problem.

  Therefore, the present inventors, based on the investigation of the cause described above, when the alumina particles are blended in the thermoplastic resin, an active group present on the surface of the alumina particles so as to suppress the hydrolysis and oxidative degradation described above. Further intensive studies were conducted to seal the. As a result, the inventors have found that the surface of the alumina particles can be modified by bringing the alumina particles into contact with a predetermined modifier at a relatively high temperature, and the above-described surface active groups and adsorbed water can be deactivated. It is a thing.

  The contact between the alumina particles and the modifier is insufficient at a temperature of less than 100 ° C., and needs to be performed at a temperature of 100 ° C. or more. Moreover, the upper limit of the temperature at the time of making it contact is 400 degreeC. Even if the contact is carried out at a temperature exceeding this temperature, the effect of the modification of the alumina particles is not further improved, the handling and the device configuration are complicated due to the high-temperature operation, and the crystals containing the alumina particles themselves in the crystal structure. Phenomena such as the release of water have undesirable effects such as alteration of alumina particles and heterogeneous structure.

  In a preferred embodiment of the present invention, the contact between the alumina particles and the modifier is performed in a liquid phase. In this case, the contact between the alumina particles and the modifier can be reliably performed, and the modification of the alumina particles and the resulting modification can be efficiently performed. When such contact is performed in the liquid phase, a predetermined organic solvent can be used and the reaction can be performed in the organic solvent. However, when the modifier is a liquid, the liquid modification can be performed without using a separate organic solvent. The contact operation can also be performed directly in the agent. Further, a predetermined resin can be used as the liquid phase, and a heated and melted resin can be used as the organic solvent.

  The thermoplastic resin composition of the present invention is characterized by containing the above-mentioned surface active groups, alumina particles deactivated by adsorbed water, and a thermoplastic resin as a base material.

  As described above, according to the present invention, the surface active groups of the alumina particles and the adsorbed water are modified with the use of a modifying agent so as to be deactivated. Therefore, the alumina particles are blended in the thermoplastic resin as a filler. Even in this case, the thermoplastic resin is not hydrolyzed or oxidized. Accordingly, the molecular weight reduction of the thermoplastic resin can be suppressed, and various properties such as strength, elastic modulus, and heat resistance of the obtained thermoplastic resin composition can be effectively improved as a filler for the alumina particles. It becomes like this. Moreover, the coloring etc. resulting from the said oxidative degradation of the said thermoplastic resin composition can be suppressed.

  Therefore, the production method of the modified alumina particle-dispersed sol of the present invention can provide alumina particles that can be put to practical use as a filler, and various properties such as strength, elastic modulus, and heat resistance can be obtained by blending the filler. Can be provided.

  Hereinafter, other features and advantages of the present invention will be described in detail based on the best mode for carrying out the invention.

(Alumina particles)
The alumina particles used in the present invention can be arbitrarily selected from commercially available ones, but are desirably alumina particles having a major axis of 5 to 500 nm. The major axis here is the length of the longest axis in anisotropic particles, that is, the length of the major axis. For isotropic particles such as regular octahedrons and spherical particles, there is no distinction between major and minor axes. It corresponds to the diameter. When the major axis is larger than 500 nm, the surface area becomes small and the interaction becomes insufficient, and the effect of improving the physical properties with respect to the thermoplastic resin cannot be obtained satisfactorily, or the product becomes brittle. If the thickness is less than 5 nm, the production process becomes complicated, aggregation tends to proceed, and this is industrially disadvantageous.

  The shape of the alumina fine particles in the present invention is not particularly limited, and not only a general polyhedron but also a rectangular parallelepiped, a plate shape, and a needle shape can be used.

  The method for producing the alumina particles is not particularly limited, and is obtained by an arbitrary method such as a gas phase method, a sol-gel method, a colloidal precipitation method, a molten metal spray oxidation method, or an arc discharge as long as the particle size can be controlled. However, as a commercially available product with relatively high anisotropy, for example, a product such as “Cataloid-AS-3” manufactured by Catalytic Chemical Industry Co., Ltd. may be mentioned.

  Among the alumina particles, particularly remarkable effect of the present invention is crystalline alumina hydrate in the form of boehmite. “Essentially” as used herein means that it is difficult industrially to obtain boehmite having a purity of 100% in the alumina synthesis process, and therefore different crystal systems other than about 5% boehmite are mixed. This means that it can be regarded as boehmite as a whole and called boehmite.

  Of the various hydrates of alumina, trihydrates such as gibbsite and vialite substantially correspond to aluminum hydroxide rather than alumina hydrate, and the high temperature reforming / inactivation treatment is performed. In many cases, the damage to the thermoplastic resin cannot be suppressed because there are many equivalents of OH groups retained as crystal water. Further, α-alumina having no water of crystallization generally has a large particle size, and it is somewhat difficult industrially to make the major axis finer to less than 500 nm. Therefore, in order to expect the interaction with the polymer, it is somewhat disadvantageous compared to boehmite.

  Furthermore, as an alumina with a small amount of water of crystallization and a large surface area, Degussa's ultrafine particulate alumina “AEROXIDE (registered trademark) Alu C”, which is δ-alumina, is mentioned. This alumina has already undergone a combustion hydrolysis process, Since coarse grains are included, it is somewhat disadvantageous compared to boehmite.

  The modifier used in the present invention is an organic compound or an inorganic compound, and is not particularly limited as long as it modifies the surface of the alumina particles described above and deactivates the surface active groups. Each may be used alone or in combination.

(Modifier)
In the case of using an organic compound, the modifier used in the present invention preferably has a solubility parameter (δ) of 15 to 35 (MPa) ^1/2 and a boiling point of 90 ° C. or higher at atmospheric pressure. The solubility parameter (δ) here is J. Brandrup, E.M. H. Immergut, E.M. A. Grulke; Polymer Handbook, 4th edition (1999, published by John Wiley & Sons, USA, Volume 1: 0-47936-5, Volume 2: 0-47936-6) Volume 2 VII / 688-VII / 694 It is a numerical value of various solvents in the table described in alphabetical order on the page. Solvent values not listed in the table are determined by the method described in Chapter VII of the publication.

When the modifier does not satisfy the solubility parameter (δ) of 15 to 35 (MPa) ^1/2 , the dispersion of the modified alumina particles in the resin when the resin composition is produced using the modified alumina sol of the present invention May decrease. Therefore, the lower limit value of the solubility parameter (δ) is preferably 18, more preferably 19, and the upper limit value thereof is preferably 32, more preferably 30.

  Such modifiers can be used singly or in combination, but in the case of a mixture of a plurality of types, it is preferable for the same reason that the solubility parameter (δ) of the mixture also satisfies the solubility parameter (δ). In the case of such a mixture, the numerical value of the sum of products obtained by multiplying the solubility parameter of each modifier (usually selected from the solvents in the table of the Polymer Handbook) by the respective mole fractions is used.

  Next, the boiling point at atmospheric pressure, which is the second requirement, will be described. The boiling point here is the boiling point of the component having the lowest boiling point among the components of the mixture when the modifier is a mixture of a plurality of types. If this is less than 100 ° C., modification effects (such as dispersibility in the resin composition and thermal stability) may be reduced. The boiling point is preferably 110 ° C. or higher, more preferably 130 ° C. or higher, and most preferably 150 ° C. or higher. On the other hand, the upper limit is not limited as long as undesirable side reactions (thermal decomposition, etc.) due to heat at the time of use do not become a problem and can be removed by distillation (may be reduced in pressure if necessary) The boiling point at a reduced pressure of 50 mmHg is usually 300 ° C., preferably 250 ° C., more preferably 220 ° C.

  The step of causing the modifier to act on the alumina particles may be performed in a pressurized state in a closed reaction vessel such as an autoclave for the purpose of increasing the temperature.

  The modifying agent is preferably an organic compound having any one of an oxygen atom, a nitrogen atom, a phosphorus atom, and a sulfur atom (hereinafter sometimes collectively referred to as a hetero atom) in the molecular structure. This is because the heteroatom has a strong solvating ability due to the property of donating a lone pair of electrons to the positively charged center (for example, hydrogen bondability and coordination bondability to a transition metal atom). This is because the ability to stabilize dispersion is estimated to be high. Specific examples of chemical structures include chemical structures having only single bonds with carbon atoms such as ether bonds and tertiary amino groups, ketone groups, aldehyde groups, carboxyl groups or their esters, carbonate bonds, urethane bonds, amide bonds, etc. And a chemical structure having a carbonyl group, an aromatic ring containing a hetero atom (such as a pyridine ring or a pyrrole ring), a sulfonic acid group or an ester thereof, a phosphoric acid group or an ester thereof, a phosphorous acid group or an ester thereof.

  Of these modifiers, it is preferable to use a modifier containing an oxycarbonyl group in the molecular structure and a modifier represented by an organic acid or an ester thereof. Examples of the modifying agent containing an oxycarbonyl group in the molecular structure include glycolic acid, lactic acid, hydroacrylic acid, glyceric acid, malic acid, tartaric acid, citric acid, and mandelic acid.

  Moreover, as a modifier represented by an organic acid or an ester thereof, for example, an organic group-substituted derivative of sulfonic acid, carboxylic acid, or phosphoric acid is desirable. These organic compounds have a hydroxyl group, a carbonyl group, a nitrogen atom, a phosphorus atom, a sulfur atom, and the like, and thereby have functional groups such as an S = O bond, a P = O bond, a C = O bond, and an OH group. Have a group.

  Therefore, strong coordination occurs with respect to AlOH groups, which are representative active groups on the surface of alumina particles, and the AlOH groups are substantially irreversible by a dehydration reaction through high-temperature treatment described in detail below. X = S, P, C) type ions are modified (ion bonds are formed). As a result, the surface modification of the alumina particles can be performed more effectively, and the surface active groups can be deactivated more efficiently. Furthermore, as a result of the deactivation of the AlOH group, the adsorbed water present on the particle surface can be removed firmly by interaction such as hydrogen bonding on the particle surface.

  As will be described in detail below, the two types of water generated as described above are volatilized from the reaction vessel, so that the drying of the alumina particles proceeds.

  On the other hand, some esters do not have OH groups in the initial state, but as a result of hydrolysis through high-temperature treatment described in detail below, many OH groups will be generated in the ester. . Therefore, with this OH group, as described above, the AlOH group, which is a typical active group on the surface of alumina particles, is reformed into substantially irreversible Al-OX (X = S, P, C) type ions. (Ion bonds are formed). As a result, the surface modification of the alumina particles can be performed more effectively, and the surface active groups can be deactivated more efficiently.

  In the organic group-substituted derivative described above, the organic group may be appropriately selected according to the type of organic component including the polymer mixed in the latter stage. For example, in the thermoplastic resin described in detail below, On the other hand, it is selected from aminoalkyl groups, epoxyalkyl groups, phenyl groups, methyl groups, ethyl groups, propyl groups, butyl groups, octyl groups, isocyanate alkyl groups, and the like.

  Specific examples of the modifier include, in the case of sulfonic acid derivatives, alkyl sulfonic acids such as methane sulfonic acid and ethane sulfonic acid, aromatics such as benzene sulfonic acid, p-toluene sulfonic acid, styrene sulfonic acid, and alkyl benzene sulfonic acid. Group sulfonic acids, esters thereof with these lower alcohols, alkali metal salts, and ammonium salts.

  In the case of carboxylic acid derivatives, acetic acid, propionic acid, butyric acid, valeric acid, stearic acid, linoleic acid, lactic acid, malonic acid, adipic acid, maleic acid, fumaric acid, acrylic acid and other alkyl carboxylic acids, benzoic acid, phthalic acid Examples include isomers, aromatic carboxylic acids such as salicylic acid, polymer carboxylic acids such as polyacrylic acid, and esters with these lower alcohols, alkali metal salts, and ammonium salts.

  In the case of phosphoric acid derivatives, phosphoric acid mono / di / trialkyl esters such as tributyl phosphate, diethyl phosphate and methyl phosphate, phosphoric acid aryl esters such as triphenyl phosphate, phosphonic acid esters such as dimethylphenyl phosphonite, tributyl phosphate Phosphites such as phyto, triphenyl phosphite, phosphine oxides such as triphenylphosphine oxide, cyclic phosphites such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, methyl Phosphonic acids such as phosphonic acid, ethyl phosphonic acid, and phenyl phosphonic acid, phosphinic acids such as methyl phosphinic acid, ethyl phosphinic acid, phenyl phosphinic acid, and diphenyl phosphinic acid, and lower alcohols thereof. Esters of alkali metal salts, ammonium salts.

  Of these specific examples, tributyl phosphite, for example, is a liquid under the conditions of the high-temperature treatment described in detail below, so that the contact between the alumina particles and the modifier described in detail below is performed in the liquid phase. It will be. In this case, the contact between the alumina particles and the modifier can be reliably performed, and the modification of the alumina particles and the resulting modification can be efficiently performed.

  In addition to the above organic compounds, organic acid anhydrides and hydrolyzable organic compounds can also be used. These reagents first remove water adsorbed to the active OH groups on the particle surface by hydrogen bonds first, and then the organic groups of the organic acid anhydrides and hydrolyzable organic compounds are the active groups. It acts on AlOH groups and deactivates them to obtain modified alumina particles. Examples of the organic acid anhydride include carboxylic anhydride and sulfonic anhydride. More specific examples include acetic anhydride, benzoic anhydride, maleic anhydride, phthalic anhydride, benzenesulfonic anhydride, and paratoluenesulfone anhydride. Such as acids. Examples of the hydrolyzable organic compound include compounds having a carbonate bond in the molecule, such as dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate, in addition to the ester compound having hydrolyzability described above. Other examples include orthoesters such as trimethyl orthoformate, triethyl orthoformate, and trimethyl orthoacetate.

(Inorganic compounds)
In the case of using an inorganic compound, the modifier used in the present invention is preferably an inorganic acid or an inorganic dehydrating reagent. As the inorganic acid, an inorganic acid or a chloride thereof can be selected. Specific examples of the inorganic acid include sulfuric acid, hydrochloric acid, nitric acid, chloric acid, chlorous acid, perchloric acid, hypochlorous acid, and phosphoric acid. Examples of the chloride are sulfate, nitrate, chloride, sulfite, nitrite, chlorate, chlorite, perchlorate, hypochlorite, phosphate. Examples thereof include sodium sulfate, calcium sulfate, sodium alum, sodium nitrate, sodium chloride, calcium chloride, potassium chlorate, and calcium phosphate. Sulfate ion, chloride ion, nitrate ion, chlorate ion, chlorite ion, perchlorate ion, and hypochlorite ion contained in these are similar to the above-mentioned organic compounds with respect to the active group AlOH group. By acting at a high temperature, the OH group can be inactivated by reforming (forming ionic bonds) to irreversible Al-OX (X = sulfate ion, chloride ion, etc.) ions. Similarly, as a result of deactivation of AlOH groups, interactions such as hydrogen bonding on the particle surface disappear, and water adsorbed on the particle surface can be easily dehydrated, resulting in dry modified alumina particles. be able to.

  As the inorganic dehydrating reagent, an inorganic acid anhydride and an inorganic dehydrating agent are used. These reagents first remove preferentially the adsorbed water adsorbed to the active OH groups on the particle surface by hydrogen bonds or the like due to the dehydrating ability of the reagents, and then the organic groups and ions of the reagents have been described above. In the same manner as described above, it can act on AlOH groups which are active groups and can be deactivated by high-temperature treatment to obtain dried modified alumina particles. Examples of the inorganic acid salt anhydride include anhydrous sodium sulfate, anhydrous magnesium sulfate, and anhydrous sodium nitrate. The inorganic dehydrating agent can be used as a so-called desiccant for organic solvents, and examples thereof include molecular sieves, calcium hydride, and sodium metal. However, these inorganic dehydrating agents have the ability to remove adsorbed water on the particle surface, water dissolved in organic solvents and resins, but have little effect on AlOH groups which are active groups. Use in combination with a modifier is preferred.

(Contact between alumina particles and modifier)
In the present invention, the above-described modifier is brought into contact with the above-described surface active group of the alumina particles when deactivated. At the time of this contact, the environmental temperature is set in a range of 100 to 400 ° C. Such a temperature range is sufficient to effectively modify the surface of the alumina particles to effectively deactivate the surface active groups, avoid high temperature operation, simplify the handling and apparatus configuration, and the alumina particles themselves. It is set to suppress structural change and heterogeneity of the material.

  When the alumina particles and the modifier are brought into contact with each other, it is preferably performed in a liquid phase in order to further improve the contact effect. When the contact in the liquid phase is performed, when the modifier is liquid in the temperature range of 100 to 400 ° C. and the pressure range of the reaction system used in the contact, the alumina particles are contained in the modifier. It is carried out by dispersing. In addition, as a modifier which can be preferably used in the present invention and exhibits a liquid in a temperature range of 100 to 400 ° C. under normal pressure, among the organic compounds exemplified above, tributyl phosphite, triphenyl phosphite, Mention may be made of cresyl phosphite and phenylphosphinic acid.

  It should be noted that, regardless of whether or not the above-described modifier is a liquid, a specific organic solvent is separately used, and the alumina particles and the modifier are dispersed and blended in the organic solvent. Can be contacted under liquid phase.

  As such an organic solvent, a solvent which is liquid in a temperature range of 100 to 400 ° C. and in a pressure range of a reaction system used for contact is used. Examples of the organic solvent that exhibits a liquid at 100 to 400 ° C. under normal pressure and can be preferably used in the present invention include aromatic hydrocarbon solvents such as toluene (boiling point 111 ° C.) and xylene (boiling point 140 ° C.), butyl acetate. Ester solvents such as (boiling point 125 ° C), ketone solvents such as cyclohexanone (boiling point 155 ° C), ether solvents such as 1,4-dioxane (boiling point 101 ° C) and ethylene glycol and its ethers, n-butanol (boiling point) 118 ° C), alcohol solvents such as cyclohexanol (boiling point 160 ° C), halogen solvents such as syn-tetrachloroethane (boiling point 146 ° C), N, N-dimethylformamide (boiling point 153 ° C), dimethyl sulfoxide (boiling point 189 ° C) And aprotic polar solvents such as

  However, the alumina particles may be in the form of a sol that has already been dispersed in another solvent including water before being dispersed in these high-boiling solvents, and the boiling point of the solvent in this case is not particularly limited.

  Moreover, when making the said alumina particle contact with a modifier | denaturant, it is preferable to prepare to the density | concentration of 2 to 50 weight% with respect to the total amount of a modifier | denaturant and / or an organic solvent. When the concentration of alumina particles is less than 2% by weight, the actual throughput per reactor is reduced, which is industrially disadvantageous. When the concentration of alumina particles exceeds 50% by weight, the fluidity is inferior, so that the contact operation cannot be performed stably and uniform surface treatment cannot be performed, resulting in modification and inactivation. May not be sufficient.

  As described above, when the contact between the alumina particles and the modifier is performed in a liquid phase, the form of the alumina particles may be powder, suspension dispersion, or cake, but the powder is preferable for handling. Desirably, the modification and deactivation time through contact can be shortened. In the case of a suspension or cake, it may take a long time for modification and deactivation.

  Specific examples of the operation for bringing the alumina particles into contact with the modifying agent include the following.

  As a reaction vessel, a general reaction vessel equipped with a cooling pipe and equipped with a heating device can be used. When an organic solvent is not used, (i) untreated alumina particles are deactivated on the surface active groups as described above. (Ii) Next, the obtained dispersion solution is set in the reaction vessel equipped with the heating device and held at 100 to 400 ° C. for 1 to 24 hours. (iii) During this time, the upper end of the cooling pipe is kept open so that it can be volatilized if there is water generated. (iv) Next, the inside of the reaction vessel is returned to room temperature in a nitrogen or dry air atmosphere, and (v) filtration and drying are performed as necessary. The obtained alumina particles are stored hermetically until composition.

  Moreover, when using an organic solvent, it implements as follows. (i) Untreated alumina particles are dispersed in a solvent exhibiting a liquid at 100 to 400 ° C. under normal pressure (having a boiling point at a temperature range of 100 to 400 ° C. or higher), and surface active groups are added. The above-described organic compound to be deactivated is dispersed. (Ii) Next, the obtained dispersion solution is set in the reaction vessel equipped with the heating device and held at 100 to 400 ° C. for 1 to 24 hours. (iii) During this time, the upper end of the cooling pipe is kept open so that it can be volatilized if there is water generated. (iv) Next, the inside of the reaction vessel is returned to room temperature in a nitrogen or dry air atmosphere, and (v) filtration and drying are performed as necessary. The obtained alumina particles are stored hermetically until composition.

  When the alumina particles are stored, the alumina particles are in the form of a sol dispersed in a predetermined organic solvent through contact with the above-described modifier. Therefore, the alumina particles are stored in the form of such an alumina particle-dispersed sol. To be able to.

  Further, it is possible to perform solvent substitution as appropriate, disperse the surface-modified and deactivated alumina particles in another organic solvent to form a sol, and store it in the form of an alumina particle-dispersed sol. Examples of such organic solvents include toluene, xylene, butyl acetate, cyclohexanone, 1,4-dioxane, ethylene glycol and its ether, butanol, cyclohexanol, tetrachloroethane, N, N-dimethylformamide, and dimethyl sulfoxide. An organic solvent selected from two or more is desirable.

  However, in the latter case, solvent replacement is performed, which is disadvantageous in terms of industrial cost. Therefore, it is preferably stored in the form of an alumina particle-dispersed sol obtained by contact with an organic compound.

  Moreover, a compatibilizing agent, a surfactant, an organic solvent, and the like can be added to the above-described alumina particle-dispersed sol as necessary.

(Thermoplastic resin composition)
The thermoplastic resin composition of the present invention contains alumina particles surface-modified and deactivated as described above and a predetermined thermoplastic resin.

  The thermoplastic resin is selected from arbitrary thermoplastic polymers. Particularly, the effect of the present invention is remarkable, and the chemical structure of the skeleton includes an ester bond, an ether bond, an amide bond, an imide bond, a urethane bond, a sulfide. Examples of the polymer include a bond and a sulfone bond. It is considered that active chemical species on the surface of alumina particles attack the relatively weak parts such as ester bonds and ether bonds contained in these thermoplastic resins in the high temperature environment during resin molding, causing hydrolysis and oxidative degradation. It is done.

  Examples of the thermoplastic resin include polycarbonate resin (PC), acrylic resin such as PMMA and PMA, polyester resin such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyarylate (PAR), polyphenylene ether (PPE), and polysulfone. (PSU), polyethersulfone (PES), polyetheretherketone (PEEK), phenoxy resin, nylon resin, polyimide resin, urethane resin, polyacetal, polyvinyl acetal, and the like.

  The concentration of the alumina particles in the thermoplastic resin composition is preferably in the range of 1 to 70% by weight as the solid content. If it is less than 1% by weight, it is difficult to recognize improvement in various properties such as mechanical strength. If it exceeds 70% by weight, an increase in specific gravity cannot be ignored, and a decrease in impact strength cannot be ignored. In general, when a large amount of inorganic fine particles are blended with a polymer, the impact strength is reduced. However, since the composition of the present invention is a uniform dispersion of nano-order alumina fine particles, the decrease in impact strength is practically small, but 70% by weight. If it exceeds, this cannot be ignored. More preferably, the content is 3 to 30% by weight.

(Method for producing thermoplastic resin composition)
As a manufacturing method of the said thermoplastic resin composition, it can select suitably according to the kind of thermoplastic resin to be used. In the case of the simplest direct kneading method, a general resin kneader may be used. For example, from a small machine such as a twin screw extruder, a vacuum microkneader extruder, a lab blast mill to a large machine, it can be used on a production scale. Select accordingly. In this example, when such a kneading method is used, the target thermoplastic resin composition is obtained by mixing the alumina particle-dispersed sol and the thermoplastic resin, which have been stored as described above, and melt-kneading. obtain.

  Another method for producing a thermoplastic resin composition is a solvent dispersion method. This method is a method in which a mixture containing a thermoplastic resin and alumina particles is used as an organic solvent dispersion, sufficiently mixed with stirring, and then the solvent is distilled off to obtain a composition. In this example, the alumina particle-dispersed sol has been prepared in advance as described above. Therefore, the thermoplastic resin is blended and dissolved in this sol, and only the solvent is distilled off under high temperature and reduced pressure to achieve the desired heat. A plastic resin composition is obtained.

  In this method, since it is necessary to dissolve the thermoplastic resin in the alumina particle-dispersed sol, the solvent constituting the sol needs to be composed of a material that can dissolve the thermoplastic resin. Specific examples include polycarbonate, tetrahydrofuran, chloroform, methylene chloride, 1,4-dioxane, cyclohexanone, tetrachloroethane, and the like.

  Examples of other methods for producing a thermoplastic resin composition include a solution polymerization method and a melt polymerization method. In the former case, the desired thermoplastic resin composition is prepared by dissolving a monomer in an alumina particle-dispersed sol prepared and stored in advance, allowing polymerization to proceed with a radical initiator, and pouring into a poor solvent after completion of the reaction. Is obtained by precipitation. This method is effective when a vinyl polymer such as an acrylic resin is used as the matrix thermoplastic resin. For example, in the case of methyl methacrylate, the composition can be precipitated by radical polymerization in toluene and pouring into hexane.

  In the latter melt polymerization method, a condensable monomer is blended and dispersed in an alumina particle-dispersed sol that has been prepared and stored in advance, and the condensation polymerization of the monomer proceeds while the solvent is distilled off while stirring under reduced pressure. And removing the resulting condensation by-product yields the desired thermoplastic resin composition. For example, in the case of polyethylene terephthalate, after mixing terephthalic acid, ethylene glycol, and alumina particle-dispersed sol, if the water produced by condensation with the solvent of the sol is distilled off by stirring, heating, and vacuum distillation, a nano composition can be obtained. Can do.

Examples are given below, but the present invention is not limited thereto.

Examples 1 to 5: High temperature reforming and inactivation of alumina particles
Example 1
“Aluminum sol-10D” (10% boehmite alumina DMF (dimethylformamide) solution) manufactured by Kawaken Fine Chemicals Co., Ltd., which is a boehmite type alumina particle dispersion (major axis length 30 nm, minor axis length 10 nm, solid content 10 wt%) 500 g of cyclohexanol was added to 500 g, and high temperature reforming / inactivation (deactivation) was performed as follows. (i) The alumina particle dispersion was placed in a glass container and stirred with a stirring blade and a three-one motor (BL300R manufactured by HEIDON). (Ii) As a modified organic compound, 10 g of phenylphosphonic acid was added and further stirred. (iii) The glass container was heated with stirring, and the temperature was raised to 150 ° C. (iv) Moisture generated from around 100 ° C. was guided to an ester trap set above the container and distilled off without returning to the system. (v) The modification was carried out for 16 hours as it was to sufficiently inactivate the surface of the alumina particles. (vi) The temperature was returned to room temperature while supplying dry air. Through this series of operations, a high temperature modified / inactivated boehmite type alumina particle cyclohexanol / DMF (dimethylformamide) dispersion was obtained.

Example 2
Example 1 except that 500 g of cyclohexanone was used instead of 500 g of cyclohexanol in Example 1 and 10 g of ethyl acid phosphate (trade name “JP-502”) manufactured by Johoku Chemical was used instead of 10 g of the modifier phenylphosphonic acid. A cyclohexanone / DMF (dimethylformamide) dispersion of boehmite-type alumina particles that had been modified and inactivated at high temperature was obtained.

Example 3
Example 1 except that 1000 g of dimethyl sulfoxide instead of 500 g of cyclohexanol in Example 1 and 10 g of ethanesulfonic acid made by Aldrich instead of 10 g of phenylphosphonic acid modifier were used and the reaction temperature was raised to 180 ° C. A dimethyl sulfoxide dispersion of boehmite-type alumina particles that had been subjected to the same operation as that described above and which had been modified and inactivated at high temperature was obtained.

Example 4
330 g of “Nanotech Alumina-Alcohol Dispersion” manufactured by C-I Kasei Co., Ltd. as an alumina particle dispersion instead of the “Aluminum Sol-10D” solution manufactured by Kawaken Fine Chemical Co., Ltd. in Example 1 (particle size 31 nm, solid content 15%) The same procedure as in Example 1 was conducted except that 1000 g of xylene was used instead of 1000 g of cyclohexanol, 10 g of benzoic acid manufactured by Wako Pure Chemical Industries was used instead of 10 g of the modifier phenylphosphonic acid, and the reaction temperature was 140 ° C. And a xylene dispersion of alumina particles subjected to high temperature reforming and inactivation was obtained.

Example 5
In place of 10 g of the modifying agent benzoic acid in Example 4, 7.5 g of concentrated sulfuric acid manufactured by Wako Pure Chemical Industries, Ltd. was used as the modified inorganic compound, and the same operation as in Example 1 was performed to perform high temperature modification / inactivation. A xylene dispersion of the resulting boehmite type alumina particles was obtained.

Example 6
500 g of the xylene dispersion of alumina particles that had been modified and deactivated at high temperature prepared in Example 4 was placed in (i) a glass container and stirred with a magnetic stirrer. (Ii) As an additional modifier, 5 g of anhydrous paratoluenesulfonic acid was added and further stirred. (Iii) The glass container was heated with stirring, and the temperature was raised to 140 ° C. (Iv) Heating and reforming were carried out for 3 hours as they were. (V) It returned to room temperature, supplying dry air. Through this series of operations, a xylene dispersion of alumina particles modified with two kinds of modifiers was obtained.

Example 7
The same operation as in Example 1, except that 1000 g of cyclohexanol and 1000 g of the modifier phenyl phosphonic acid in Example 1 were used instead of 1000 g of tributyl phosphite as a solvent and modifier and the reaction temperature was 250 ° C. To obtain boehmite-type alumina particles that have been modified and deactivated at high temperature, and then filtered through a membrane filter and re-dispersed in 1000 g of dimethylformamide to obtain a dimethylformamide dispersion of boehmite-type alumina particles. Obtained.

Examples 8 to 16: Alumina particle-containing resin composition
Example 8 (solution mixing)
In 500 g of the boehmite type alumina particle dispersion (solid content: about 5%) prepared in Example 1, 75 g of polycarbonate “Novalex 7025A” (weight average molecular weight 54000) manufactured by Mitsubishi Engineering Plastics Co., Ltd. was dissolved in 400 g of methylene chloride. Things were added to make a uniform solution. The solvent is removed while gradually increasing the degree of vacuum. Finally, the solvent is distilled off at 100 ° C. under a reduced pressure of 1 Torr or less for 4 hours, and the mixture is further manufactured by Imoto Seisakusho “Vacuum microkneading extruder IMC-1170B type”. And kneaded at 260 ° C. for 15 minutes to obtain a resin composition. The ash content of the product was 23.5 wt%, and it was confirmed that the added alumina particles were almost entirely composed.

  This product had a colorless and almost transparent appearance, was not yellowed, and retained toughness. The impact strength (Izod) was 339 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 49700, and the initial molecular weight was almost maintained. When this composition was made into a 5% dimethylformamide solution and cast to a thickness of about 100 μm on a flat glass plate, a highly transparent and strong film was obtained.

Example 9 (solution mixing)
The same operation as in Example 8 was performed using 500 g of the boehmite-type alumina particle dispersion (solid content: about 5%) prepared in Example 2. The ash content of the product was 22.7 wt%, and it was confirmed that the added alumina particles were almost entirely composed. This product had a colorless and almost transparent appearance, was not yellowed, and retained toughness. The impact strength (Izod) was 274 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 47900, and the initial molecular weight was almost maintained.

Example 10 (melt polymerization)
In Example 3, zinc acetate 18 mg (0.1 mmol) was added as a catalyst to Kanto Chemical Co., Ltd. ethylene glycol 124.1 g (2 mol) and Kanto Chemical Co., Ltd. dimethyl terephthalic acid 194.2 g (1 mol). 240 g of the adjusted boehmite type alumina particle dispersion (solid content: about 5%) is added, the temperature is gradually raised to 195 ° C. while gradually increasing the degree of vacuum, and the solvent and water generated are sufficiently removed, and the transesterification proceeds. Then, the mixture was polymerized at 280 ° C. under a reduced pressure of 3 mTorr or less for 3 hours, and further kneaded at 280 ° C. for 15 minutes to obtain a resin composition.

  The ash content of the product was 5.0 wt%, and it was confirmed that almost all of the added alumina was composed. This composition was colorless and translucent, did not yellow, and had toughness. The impact strength (Izod) was 88 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 58,000, and a sufficient high molecular weight was maintained.

Example 11 (Solution polymerization)
In 400 mL of toluene, 100.1 g (1 mol) of methyl methacrylate manufactured by Kanto Chemical Co., Ltd., and 12.2 g (0.05 mol) of V-40 manufactured by Wako Pure Chemical Industries, Ltd. as a radical initiator were added. 900 g of the alumina particle dispersion (solid content: about 5%) prepared in Example 4 was added, the temperature was raised to 90 ° C. to initiate radical reaction, and polymerization was continued for 3 hours while stirring. After the reaction, the reaction solution was poured into 2 L of hexane, subjected to high temperature reforming / inactivation at 80 ° C. under reduced pressure of 1 Torr or less for 4 hours, and then kneaded at 200 ° C. for 15 minutes to obtain a resin composition.

  The ash content of the product was 32.2 wt%, and it was confirmed that the added alumina was almost entirely composed. This composition was colorless and transparent, did not yellow, and had some toughness. The impact strength (Izod) was 37 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 66000, and a sufficient high molecular weight was maintained.

Example 12 (solution mixing)
The same operation as in Example 8 was performed using 500 g of boehmite-type alumina particle dispersion (solid content: about 5%) prepared in Example 5 and 75 g of methacrylic resin “Acrypet Standard Grade V” manufactured by Mitsubishi Rayon Co., Ltd. The ash content of the product was 21.2 wt%, and it was confirmed that the added alumina particles were almost entirely composed. This product had a colorless and almost transparent appearance, was not yellowed, and retained toughness. The impact strength (Izod) was 240 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 70000, and the initial molecular weight was almost maintained.

Example 13 (solution mixing)
The same operation as in Example 8 was performed using 500 g of the boehmite-type alumina particle dispersion (solid content: about 5%) prepared in Example 6 and 75 g of methacrylic resin “Acrypet Standard Grade V” manufactured by Mitsubishi Rayon Co., Ltd. The ash content of the product was 23.5 W%, and it was confirmed that the added alumina particles were almost entirely composed. This product had a colorless and almost transparent appearance, was not yellowed, and retained toughness. The impact strength (Izod) was 270 J / m.
When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 78000, and the initial molecular weight was almost maintained.

Example 14 (solution mixing)
The same operation as in Example 8 was performed using 500 g of the boehmite-type alumina particle dispersion (solid content: about 5%) prepared in Example 5. The ash content of the product was 25.1 wt%, and it was confirmed that the added alumina particles were almost entirely composed. This product had a faint yellow, almost transparent appearance and retained toughness. The impact strength (Izod) was 374 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 50100, and the initial molecular weight was almost maintained.

  In the comparative example, a case where sufficient heating operation was not performed in the high temperature reforming / inactivation of the alumina particles in the above example is described.

Example 15 (Surface modification and resin composition)
30 g of polycarbonate “Novalex 7025A” manufactured by Mitsubishi Engineering Plastics Co., Ltd. was added to “IMC-1170B type vacuum micro-kneading extruder IMC” manufactured by Imoto Seisakusho, and kneaded at 260 g for 3 minutes. Clay-like solids concentrated with 100 g of “Aluminum sol-10” (10% boehmite alumina aqueous solution) manufactured by Kawaken Fine Chemical Co., Ltd., a boehmite-type alumina particle dispersion prepared in advance, and butoxy manufactured by Johoku Chemical 2 g of ethyl acid phosphate (trade name “JP-506H”) was added and kneaded for 10 minutes under vacuum to obtain a resin composition. The ash content of the product was 23.0 wt%, and it was confirmed that the added alumina particles were almost entirely composed. The impact strength (Izod) was 35 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 49000, and the initial molecular weight was almost maintained.

Example 16 (Surface modification and resin composition)
(Inc.) Imoto Seisakusho "vacuum micro-kneading extruder IMC-1170B type" 30 g of the resin composition obtained in Example 8 and 4 g of diphenyl carbonate as an additional modifier are placed in a vacuum for 250 minutes. The resin composition was obtained by kneading at ° C. The ash content of the product was 20.0 wt%, and the impact strength (Izod) was 40 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 48000.

Comparative Example 1.
1-1: Alumina particle-dispersed boehmite type alumina particle dispersion “Aluminum Sol-10D” (10% boehmite alumina DMF (dimethylformamide) solution) (major axis length 30 nm, minor axis length) manufactured by Kawaken Fine Chemical Co., Ltd. (10 nm, solid content 10 wt%) 500 g of cyclohexanol was added and the following operation was performed. (i) The alumina particle dispersion was placed in a glass container and stirred with a stirring blade and a three-one motor (BL300R manufactured by HEIDON). (ii) As a modifier, 10 g of phenylphosphonic acid was added and further stirred. (iii) The glass container was heated with stirring, and the temperature was raised to 80 ° C. (iv) Mixing was continued for 16 hours. (v) Moisture was distilled off with a vacuum pump at 80 ° C., and at the same time, while distilling off cyclohexanol, the distillation was continued until almost no water was left in the system. (vi) The temperature was returned to room temperature while supplying dry air. Through this series of operations, a cyclohexanol dispersion of non-high temperature modified alumina particles was obtained.

1-2: Composition (solution mixing)
Using 300 g of the alumina particle dispersion liquid (solid content: about 5%) prepared in 1-1 above, 85 g of polycarbonate “Novalex 7025A” (weight average molecular weight 54000) and resin composition were obtained by the same solution mixing operation as in Example 8. Materialized. The ash content of the product was 14.2 wt%. This product had a yellowish amber appearance and poor toughness, and even a 2 mm thick sample plate could be broken by hand. The impact strength (Izod) remained at 14 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 9600, which was greatly reduced from the initial molecular weight.

Comparative Example 2.
2-1: Alumina particle dispersion In the same manner as in Example 2, 1000 g of cyclohexanone was used as a solvent, and 10 g of ethyl acid phosphate (trade name “JP-502”) manufactured by Johoku Chemical was used as a modifier. A cyclohexanone dispersion of non-high temperature modified alumina particles was obtained by performing an operation suppressed to ℃.

2-2: Composition (solution mixing)
Using the dispersion liquid of Comparative Example 2-1, a resin composition was prepared so as to have a polycarbonate “NOVAREX 7025A” (weight average molecular weight of 54000) and a solid content of 15 wt% in the same manner as in 1-2 above. The ash content of the product was 14.6 wt%. The product had a brown appearance, poor toughness, and impact strength (Izod) remained at 26 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 14,000, which was greatly reduced from the initial molecular weight.

Comparative Example 3.
3-1: Alumina particle dispersion As in Example 3, 1000 g of dimethyl sulfoxide was used as the solvent, 10 g of ethanesulfonic acid manufactured by Aldrich was used as the modifier, and the operation was suppressed to 80 ° C. as in Comparative Example 1, A dimethyl sulfoxide dispersion of non-high temperature modified alumina particles was obtained.

3-2: Composition (solution polymerization)
As in Example 11, 100.1 g (1 mol) of methyl methacrylate and 12.2 g (0.05 mol) of a radical initiator were added to 400 mL of toluene, and the alumina particle dispersion prepared in Comparative Example 3-1 above. 900 g of (solid content of about 5%) was added to form a composition by radical polymerization. This product had a yellowish pale brown appearance and poor toughness, and even a 2 mm thick sample plate could be easily broken by hand. The impact strength (Izod) remained at 10 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 22,000, which was significantly lower than the molecular weight of Example 11.

Comparative Example 4.
4-1: Alumina Particle Dispersion As in Example 4, 1000 g of xylene was used as the solvent, 10 g of benzoic acid manufactured by Aldrich was used as the modifier, and the operation was suppressed to 80 ° C. as in Comparative Example 1, and the temperature was not high. A xylene dispersion of modified alumina particles was obtained.

4-2: Composition (solution polymerization)
As in Example 11, 100.1 g (1 mol) of methyl methacrylate and 12.2 g (0.05 mol) of a radical initiator were added to 400 mL of toluene, and the alumina particle dispersion prepared in Comparative Example 4-1 above. 900 g of (solid content of about 5%) was added to form a composition by radical polymerization. This product had a yellowish reddish brown appearance and extremely poor toughness, and even a sample plate having a thickness of 3 mm could be easily broken by hand. The impact strength (Izod) remained at 9 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 19000, which was significantly lower than the molecular weight of Example 11.

Comparative Example 5
5-1: Alumina Particle Dispersion As in Example 7, 1000 g of tributyl phosphite was used as a solvent and modifier, and as in Comparative Example 1, the operation was suppressed to 80 ° C., and filtration and solvent replacement were performed. A dimethylformamide dispersion of high temperature modified alumina particles was obtained.

5-2: Composition (solution mixing)
Using the dispersion liquid of Comparative Example 5-1, in the same manner as in Comparative Example 1-2, a resin composition was prepared so as to have a polycarbonate “Novalex 7025A” (weight average molecular weight 54000) and a solid content of 15 wt%. The ash content of the product was 15.3 wt%. The product had a light brown appearance, poor toughness, and impact strength (Izod) remained at 46 J / m. When the matrix polymer content of the composition was extracted and analyzed by GPC, the weight average molecular weight was 13,000, which was significantly lower than the initial molecular weight.

  The characteristic values of the thermoplastic resin compositions obtained through Examples and Comparative Examples are summarized in Table 1.

  As is clear from Table 1, when Examples 6 to 10 are compared with the corresponding Comparative Examples 1 to 5, respectively, the same organic solvent and the same modified organic compound are used for the alumina particles. Nevertheless, it can be seen that for those treated at a temperature of 80 ° C., which is outside the scope of the present invention, the weight average molecular weight is greatly reduced and the impact strength is also greatly reduced. That is, in the examples carried out according to the present invention, the modification of the surface of the alumina particles by the modified organic compound has sufficiently progressed, and the surface active groups have been sufficiently deactivated. When the surface modification of the alumina particles is performed at (low temperature), it can be seen that the surface modification is not sufficiently performed and the surface active groups are not sufficiently deactivated.

  The present invention has been described in detail above with reference to specific examples. However, the present invention is not limited to the above contents, and various modifications and changes can be made without departing from the scope of the present invention.

  For example, the thermoplastic resin composition of the present invention optionally contains an antioxidant and a heat stabilizer (for example, including hindered phenol, hydroquinone, thioether, phosphites, and their substituted products and combinations thereof), UV absorbers (for example, resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants, mold release agents (for example, silicon resin, montanic acid and its salts, stearic acid and its salts, stearyl alcohol, stearylamide, etc.), dyes (for example, nitrocin) Etc.), colorants including face departments (for example, cadmium sulfide, phthalocyanine, etc.), additive additives (for example, silicone oil), crystal nucleating agents (for example, talc, kaolin, etc.), etc. Can do.

  Specifically, in order to improve thermal stability, partially acrylated polyphenols represented by hindered phenols such as Irganox 1010 and 1076 (manufactured by Ciba-Geigy), Sumilizer GS, and GM (manufactured by Sumitomo Chemical Co., Ltd.) An appropriate amount of a heat stabilizer such as a phosphorus compound typified by phosphites such as Irgafos 168 (manufactured by Ciba Geigy) may be added.

  According to the present invention, since the surface active groups of the alumina particles are sufficiently deactivated, the alumina particles can be blended as a filler without adversely affecting the intended resin composition. Therefore, the mechanical strength and dimensional stability of the obtained (nano) thermoplastic resin composition can be improved by the various properties inherent to the thermoplastic resin and the interaction of the alumina particles as a filler. It becomes like this. As a result, it can be suitably used for electronic parts, optical parts, interior / exterior materials for automobiles, and transparent members / equipment / furniture used for home appliances and houses, which are subjected to heat cycle load. In addition, by using a thin film or a coating agent, durability, weather resistance, and abrasion resistance are improved, so that it can be suitably used for home appliances, housing equipment, electrical / electronic components, and optical components.

Claims (21)

  The modified alumina particle dispersion is characterized in that, when the alumina particles are modified and modified by bringing the alumina particles into contact with a modifying agent, the contact between the alumina particles and the modifying agent is performed in a temperature range of 100 to 400 ° C. A method for producing a sol.   The method for producing a modified alumina particle-dispersed sol according to claim 1, wherein the contact between the alumina particles and the modifier is performed in a liquid phase.   The method for producing a modified alumina particle-dispersed sol according to claim 1 or 2, wherein the contact between the alumina particles and the modifier is performed in a predetermined organic solvent.   The said modifier is a liquid in a temperature range of 100 to 400 ° C. under normal pressure, and the alumina particles are brought into contact with the modifier by mixing and dispersing in the modifier. Or 3. A method for producing a modified alumina particle-dispersed sol according to 3.   The method for producing a modified alumina particle-dispersed sol according to claim 1, wherein the contact between the alumina particles and the modifier is performed in a predetermined molten resin. 6. The method according to claim 1, wherein the modifier is an organic compound, the solubility parameter (δ) is 15 to 35 (MPa) ^1/2 , and the boiling point at atmospheric pressure is 90 ° C. or higher. A method for producing a modified alumina particle-dispersed sol according to claim 1.   The method for producing a modified alumina particle-dispersed sol according to claim 6, wherein the modifying agent contains an oxycarbonyl group in the molecular structure.   The method for producing a modified alumina particle-dispersed sol according to claim 6, wherein the modifier is an organic acid or an ester thereof.   The method for producing a modified alumina particle-dispersed sol according to any one of claims 1 to 5, wherein the modifier is an inorganic compound and is an inorganic acid and / or an inorganic dehydrating reagent.   10. The modified alumina particle-dispersed sol according to claim 9, wherein the inorganic agent is at least one selected from the group consisting of nitric acid, sulfuric acid, hydrochloric acid, chloric acid, perchloric acid, and hypochlorous acid. Production method.   The method for producing a modified alumina particle-dispersed sol according to claim 9, wherein the dehydrating reagent is an inorganic acid salt anhydride or an organic solvent desiccant.   The modification according to any one of claims 1 to 11, wherein at least a part of the active substance existing on the surface of the alumina particles is deactivated by bringing the alumina particles into contact with the modifying agent. A method for producing an alumina particle-dispersed sol.   The method for producing a modified alumina particle-dispersed sol according to any one of claims 1 to 12, wherein the alumina particles are essentially crystalline alumina-hydrate in the form of boehmite.   A method for producing modified alumina particles, which is obtained from the modified alumina particle-dispersed sol according to any one of claims 1 to 13.   A modified alumina particle obtained from the modified alumina particle-dispersed sol according to any one of claims 1 to 13.   A thermoplastic resin composition is produced by mixing the alumina particle-dispersed sol obtained by the production method according to any one of claims 1 to 13 and the thermoplastic resin, and melt-kneading the mixture. A method for producing a thermoplastic resin composition.   A thermoplastic resin composition is obtained by dispersing and mixing a thermoplastic resin in the alumina particle-dispersed sol obtained by the production method according to any one of claims 1 to 13, and distilling off only the solvent under high temperature and reduced pressure. The manufacturing method of the thermoplastic resin composition characterized by manufacturing.   A thermoplastic resin composition is produced by blending a monomer of a thermoplastic resin in the alumina particle-dispersed sol obtained by the production method according to any one of claims 1 to 13 and polymerizing the monomer. The manufacturing method of the thermoplastic resin composition characterized by the above-mentioned.   The repeating unit of the chemical structure of the thermoplastic resin includes at least one selected from the group consisting of an ester bond, an ether bond, an amide bond, an imide bond, a urethane bond, a sulfide bond, and a sulfone bond. Item 19. A method for producing a thermoplastic resin composition according to any one of Items 16 to 18.   The thermoplastic resin composition according to any one of claims 16 to 19, wherein the concentration of the alumina particles in the thermoplastic resin composition is 1 to 70% by weight as a solid content. Production method.   A thermoplastic resin composition obtained by the method for producing a thermoplastic resin composition according to any one of claims 16 to 20.