JP6560136B2 - Hydroxide mineral dispersion and method for producing the same - Google Patents

Description

The present invention, functional inorganic filler is a hydroxide mineral dispersion obtained by dispersing a hydroxide minerals in the nonaqueous dispersing medium, and 及 Beauty manufacturing method thereof.

  Hydroxide minerals are inorganic compounds that have a hydroxyl group (OH group) on their surface, obtained from minerals such as diaspore, goethite, water talc, and gibbstone, or obtained by chemical synthesis. Hydroxide minerals are abundant on the earth, are stable and environmentally friendly, have little concern about resource depletion, and are known as safe compounds for the human body. Furthermore, since it is a natural material, it can appeal its superiority as an environmental measure, and it is also a feature that it is an inexpensive material. Examples of the use of such a hydroxide mineral include a reinforcing material, a filler, a flame retardant filler, an adsorbent, a catalyst, and a pharmaceutical. Furthermore, in recent years, use as a flame retardant for heat conductive materials and electromagnetic wave shielding materials has been studied, and optical characteristics have been improved in the electronics field such as electronic parts, electronic devices, semiconductors, and liquid crystal displays. It is being used as a material for

  Various studies and proposals have been made regarding the performance and dispersibility of hydroxide minerals. For example, a highly thermally conductive boehmite having characteristics such as flame retardancy and high filling property and improved thermal conductivity has been proposed (Patent Document 1). Moreover, dispersibility is high when the surface of the inorganic hydroxide is treated with carbodiimide, which is highly dispersible even when highly filled in the resin, and can suppress deterioration of properties such as electrical properties and mechanical properties of the obtained molded product. Flame retardant has been proposed (Patent Document 2). Further, magnesium hydroxide surface-treated with a silicone oil made of a predetermined polysiloxane, which is imparted with flame retardancy while maintaining mechanical properties such as elongation, has been proposed (Patent Document 3).

International Publication No. 2014/073228 JP 2012-254930 A JP 2010-031271 A

  It is difficult to disperse a hydroxide mineral that is a highly hydrophilic inorganic substance in an organic solvent or a thermoplastic resin that is a hydrophobic material. For this reason, in order to disperse the hydroxide mineral easily in the hydrophobic material, various surface modification treatments of the hydroxide mineral have been studied. For example, the affinity of a hydrophilic material for a hydrophobic material such as a dispersion medium as proposed in Patent Documents 2 and 3 is increased by treating the surface of the hydrophilic material, thereby improving the dispersibility in the dispersion medium. Techniques to improve are being studied. However, the methods proposed in Patent Documents 2 and 3 have a problem that the process is complicated. In addition, since the treatment is performed in an organic solvent, there is a problem that the environment is burdened from an industrial point of view even though the hydroxide mineral to be treated is a natural material. Furthermore, there is a problem that it is difficult to sufficiently treat the surface of the hydroxide mineral.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to provide a dispersion stability in which a hydroxide mineral is stably dispersed in a hydrophobic dispersion medium. It is to provide a hydroxide mineral dispersion excellent in the above and a method for producing the same. The subject of the present invention is an organic-inorganic composite material useful as a material for obtaining the hydroxide mineral dispersion and a method for producing the same; and the hydroxide mineral constituting the hydroxide mineral dispersion is hydrophobic. Another object of the present invention is to provide an AB block copolymer useful as a filler dispersant that is stably dispersed in a dispersion medium, and a method for producing the same.

That is, according to the present invention, the following hydroxide mineral dispersion is provided.
[1] A hydroxide mineral dispersion containing a hydroxide mineral, a non-aqueous dispersion medium, and a filler dispersant for dispersing the hydroxide mineral in the non-aqueous dispersion medium, wherein the hydroxide mineral is hydroxylated It is at least one selected from the group consisting of magnesium, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide, and the filler dispersant is derived from a methacrylic acid monomer A polymer block containing 90% by mass or more of units, having a number average molecular weight of 4,000 or more and 20,000 or less, and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 1.6 or less. AB block copolymer comprising a B polymer block, the A polymer block comprising an alkyl methacrylate, a cycloalkyl A structural unit derived from at least one selected from the group consisting of tacrylate, alkylcycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate, cycloalkenoxyalkyl methacrylate, and aryloxyalkyl methacrylate. While containing 80% by mass or more, the number average molecular weight is 3,000 or more and 15,000 or less, and the molecular weight distribution (weight average molecular weight / number average molecular weight) is 1.5 or less. While containing the structural unit derived from the methacrylic acid-type monomer which has a carboxy group, an acid value is 100 mgKOH / g or more and 652 mgKOH / g or less, and the number average molecular weight is the said Or less the number-average molecular weight of the polymer block, wherein the non-aqueous dispersion medium is an aprotic organic solvent solubility in 25 ° C. water is below 20 g / L, or a thermoplastic resin in which hydroxide mineral dispersion.
[2] The content of the filler dispersant is 5 to 50% by mass of the hydroxide mineral, the number average particle diameter of the hydroxide mineral is 500 nm or less, and 100 parts by mass of the hydroxide mineral. The hydroxide mineral dispersion according to [1], in which is 20 to 200 parts by mass.

Furthermore, according to this invention, the manufacturing method of the hydroxide mineral dispersion shown below is provided.
[4] the [1] or [2] A method of manufacturing a hydroxide mineral dispersion according to the organic-inorganic composite material, have a step of dispersing in the nonaqueous dispersing medium, wherein the organic-inorganic The composite material includes a hydroxide mineral and a polymer, and the hydroxide mineral is selected from the group consisting of magnesium hydroxide, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide. And the polymer contains 90% by mass or more of a structural unit derived from a methacrylic acid monomer, has a number average molecular weight of 4,000 to 20,000, and a molecular weight distribution (weight) Average molecular weight / number average molecular weight) is an AB block copolymer containing an A polymer block and a B polymer block, and having the A polymer block The alkyl is selected from the group consisting of alkyl methacrylate, cycloalkyl methacrylate, alkyl cycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate, cycloalkenyloxyalkyl methacrylate, and aryloxyalkyl methacrylate. And a number average molecular weight of 3,000 to 15,000 and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 1.5 or less. The B polymer block contains a structural unit derived from a methacrylic acid monomer having a carboxy group, and has an acid value of 100 mgKOH / g or more and 652 m. KOH / g or less, and, the manufacturing method of the number average molecular weight is a number average molecular weight less der Ru hydroxide mineral dispersion of the A polymer block.

  ADVANTAGE OF THE INVENTION According to this invention, the hydroxide mineral dispersion excellent in the dispersion stability in which the hydroxide mineral was stably disperse | distributed in the hydrophobic dispersion medium, and its manufacturing method are provided. In addition, according to the present invention, an organic-inorganic composite material useful as a material for obtaining the hydroxide mineral dispersion and a method for producing the same; and the hydroxide mineral constituting the hydroxide mineral dispersion as a hydrophobic dispersion medium An AB block copolymer useful as a filler dispersant that is stably dispersed therein and a method for producing the same are provided.

  Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. As a result of intensive studies, the present inventors have found that a polymer having a unique structure formed by living radical polymerization is extremely useful as a filler dispersant that can disperse a hydroxide mineral in a good dispersion state in a non-aqueous dispersion medium. The inventors have found that the present invention has been completed. That is, the hydroxide mineral dispersion of the present invention contains 90% by mass or more of a structural unit derived from a methacrylic acid monomer, has a number average molecular weight of 4,000 to 20,000, and a molecular weight distribution ( The AB block copolymer containing A polymer block and B polymer block whose weight average molecular weight / number average molecular weight) is 1.6 or less is contained as a filler dispersant.

  Hydroxide mineral is an inorganic compound having a hydroxyl group (OH group) on its surface. On the other hand, the AB block copolymer used as a filler dispersant is composed of an A polymer block that is a polymer chain that can be dissolved and compatible with a non-aqueous dispersion medium, and a B polymer block having a carboxy group. The carboxy group in the B polymer block forms an ionic bond with an OH group present on the surface of the hydroxide mineral, or a hydrogen bond with an OH group or an oxygen atom. As a result, the B polymer block is adsorbed on the hydroxide mineral, and it is considered that the adsorption of the B polymer block and the hydroxide mineral is difficult to dissociate in the hydrophobic non-aqueous dispersion medium. In addition, since the A polymer block is a block that dissolves and is compatible with the hydrophobic non-aqueous dispersion medium, the aggregation of the hydroxide mineral is suppressed by steric repulsion, and the dispersion state of the hydroxide mineral is maintained in a good state. be able to. Therefore, the hydroxide mineral dispersion of the present invention containing such an AB block copolymer as a filler dispersant has a low viscosity and a stable dispersibility over a long period of time. Furthermore, since the hydroxide mineral has a high specific gravity, even if it is settled in a liquid medium, it can be easily returned to its original dispersed state by lightly stirring.

<Hydroxide mineral dispersion>
The hydroxide mineral dispersion of the present invention contains a hydroxide mineral, a non-aqueous dispersion medium, and a filler dispersant for dispersing the hydroxide mineral in the non-aqueous dispersion medium. Hereinafter, each component which comprises the hydroxide mineral dispersion of this invention is demonstrated in detail.

(Hydroxide mineral)
The hydroxide mineral is at least one selected from the group consisting of magnesium hydroxide, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide. Since these hydroxide minerals are inorganic oxides, they have various crystal forms. For example, α-, β-, γ-, and δ- are known for aluminum hydroxide. In the present invention, any crystal form may be used. Examples of the shape of the hydroxide mineral include acicular, planar, plate-like, scale-like, cube, disc-like, granular, powdery, and spherical shapes. In the present invention, any shape of a mineral hydroxide may be used. Further, the hydroxide mineral may be a natural mineral or may be obtained by chemical synthesis. Chemical synthesis includes neutralization reaction with alkali, precipitation from a supersaturated state, hydrolysis of metal alkoxide, and thermal synthesis of hydroxide.

  Although the number average particle diameter of the hydroxide mineral varies depending on the particle shape and the use of the hydroxide mineral dispersion, it cannot be generally stated, but it is preferably 500 nm or less, more preferably 200 nm or less. When the number average particle size of the hydroxide mineral is within the above range, the performance of the hydroxide mineral can be exhibited well. On the other hand, if the number average particle size of the hydroxide mineral is too large, the appearance tends to be opaque, and it may be difficult to achieve gloss and transparency. The number average particle diameter of the hydroxide mineral can be measured by, for example, microscopic observation or light scattering measurement.

  In addition, complex hydroxide minerals, such as magnesium calcium hydroxide, can also be used as a hydroxide mineral. Such a complex hydroxide mineral can be obtained, for example, by coprecipitation of magnesium chloride and calcium chloride. Moreover, the inorganic filler which surface-treated by providing a hydroxide mineral to the surface of inorganic fillers, such as a titanium oxide, a zinc oxide, a calcium carbonate, a silica, can also be used as needed.

  The content of the hydroxide mineral in the hydroxide mineral dispersion is preferably 5 to 50% by mass, and more preferably 10 to 40% by mass. When the content of the hydroxide mineral is less than 5% by mass, the properties as a filler may be hardly exhibited. On the other hand, when the content of the hydroxide mineral is more than 50% by mass, the viscosity may be too high when the liquid medium is used as the non-aqueous dispersion medium. Moreover, when a thermoplastic resin is used as the non-aqueous dispersion medium, the filling rate may be too high, and kneading may be difficult.

  The content of the filler dispersant with respect to 100 parts by mass of the hydroxide mineral is preferably 20 to 200 parts by mass, and more preferably 25 to 100 parts by mass. When the filler dispersant content is less than 20 parts by mass with respect to 100 parts by mass of the hydroxide mineral, the storage stability of the hydroxide mineral may be insufficient. On the other hand, if the filler dispersant content exceeds 200 parts by mass with respect to 100 parts by mass of the hydroxide mineral, the filler dispersant becomes excessive. For this reason, when a liquid medium is used as the non-aqueous dispersion medium, the viscosity may become too high. Furthermore, the physical properties of the AB block copolymer used as the filler dispersant are remarkably easily expressed, and the desired physical properties of the non-aqueous dispersion medium may be difficult to be exhibited.

(Filler dispersant (AB block copolymer))
The filler dispersant used in the hydroxide mineral dispersion of the present invention is an AB block copolymer containing an A polymer block and a B polymer block. The AB block copolymer contains 90% by mass or more, preferably 95% by mass or more, and most preferably 100% by mass of a structural unit derived from a methacrylic acid monomer. A preferred method for producing the AB block copolymer described below is a polymerization method in which a methacrylic acid monomer is preferably used. In this production method, when a vinyl monomer such as styrene, an acrylate monomer, or a vinyl ether monomer is used, iodine bonded to the polymerization terminal is over-stabilized, and there is a need for heating to dissociate, Alternatively, there is a possibility that inconveniences such as no dissociation occur even when heated. Therefore, if a large amount of a monomer other than a methacrylic acid monomer is used, there is a possibility that a AB block copolymer having a desired specific structure cannot be obtained or a molecular weight distribution is excessively widened. is there. However, a monomer other than the methacrylic acid-based monomer may be used as necessary as long as the object of the present invention is not impaired.

  The number average molecular weight (Mn) of the AB block copolymer is 4,000 or more and 20,000 or less, preferably 5,000 or more and 15,000 or less. When the Mn of the AB block copolymer is less than 4,000, the dispersion stability of the resulting hydroxide mineral dispersion decreases. On the other hand, if the Mn of the AB block copolymer is more than 20,000, when the liquid medium is used as the non-aqueous dispersion medium, the viscosity may become too high or the dispersibility of the hydroxide mineral may be lowered. . In addition, “number average molecular weight (Mn)” in the present specification is a molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  The molecular weight distribution (weight average molecular weight / number average molecular weight) of the AB block copolymer is 1.6 or less, preferably 1.5 or less. When the molecular weight distribution (hereinafter also referred to as “PDI”) of the AB block copolymer is more than 1.6, a polymer that is out of the range of the number average molecular weight (Mn) is likely to be contained. The dispersion stability of the mineral dispersion may be reduced.

  When the AB block copolymer is produced (polymerized), either the A polymer block or the B polymer block may be polymerized first. However, it is preferable to polymerize the B polymer block after polymerizing the A polymer block. When the B polymer block is formed first using a methacrylic acid monomer having a carboxy group, the polymerization rate is low, and if the methacrylic monomer having a carboxy group remains, the carboxy group is easily introduced into the A polymer block. . If a carboxy group is also introduced into the A polymer block, the dispersion stability of the resulting hydroxide mineral dispersion may be insufficient.

[A polymer block]
The A polymer block has a function of affinity and dissolution in a hydrophobic non-aqueous dispersion medium and suppressing aggregation of hydroxide minerals due to steric hindrance and steric repulsion. The A polymer block also has a property of being compatible with other polymers used in pigment dispersions and the like.

  The A polymer block is selected from the group consisting of alkyl methacrylate, cycloalkyl methacrylate, alkyl cycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate, cycloalkenyloxyalkyl methacrylate, and aryloxyalkyl methacrylate. It contains a structural unit derived from at least one kind. The content of the structural unit in the A polymer block is 80% by mass or more, preferably 90% by mass or more. In addition, it is preferable that A polymer block does not contain the structural unit derived from the methacrylic acid type monomer which has a carboxy group contained in B polymer block substantially.

  Specific examples of the monomer constituting the structural unit include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, 2-methylpropane methacrylate, t-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, octyl methacrylate, 2 -Linear or branched alkyl methacrylates such as ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, isodecyl methacrylate, lauryl methacrylate, tetradecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, isostearyl methacrylate; cyclohexyl methacrylate, tricyclodecyl Methacrylate, isobornyl methacrylate Cycloalkyl methacrylates such as t-butylcyclohexyl methacrylate and trimethylsiloxane methacrylate; aryl methacrylates such as phenoxy methacrylate and naphthyl methacrylate; arylalkyl methacrylates such as benzyl methacrylate; Alkoxyalkyl methacrylates such as methoxyethyl methacrylate, ethoxyethyl methacrylate, butoxyethyl methacrylate, and lauroxyethyl methacrylate; cycloalkoxyalkyl methacrylates such as cyclohexyloxyethyl methacrylate; cycloalkenoxy such as dicyclopentenyloxyethyl methacrylate , And the like aryloxyalkyl methacrylate such as phenoxyethyl methacrylate; Le kill methacrylate.

  You may use the other methacrylic acid-type monomer which can be copolymerized with said monomer. However, it is preferable to avoid the use of a monomer that easily reacts with a carboxy group or a highly hydrophilic monomer. Examples of the monomer that easily reacts with a carboxy group include glycidyl methacrylate, methacryloyloxyethyl isocyanate, oxetanyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and t-butylaminoethyl methacrylate. Examples of the highly hydrophilic monomer include phosphonylethyl methacrylate.

  Examples of other methacrylic monomers include, for example, methacrylates having a hydroxyl group such as hydroxyethyl methacrylate and hydroxypropyl methacrylate; halogen-containing methacrylates such as tetrafluoroethyl methacrylate; 2- (4-benzoxy-3-hydroxyphenoxy) ethyl methacrylate, Methacrylate capable of absorbing ultraviolet rays such as 2- (2′-hydroxy-5-methacryloyloxyethylphenyl) -2H-benzotriazole; in addition to silicon-containing methacrylates having trimethoxysilyl groups and dimethylsilicone chains; tetrahydrofurfuryl A methacrylate etc. can be mentioned.

  The number average molecular weight (Mn) of the A polymer block is 3,000 to 15,000, preferably 5,000 to 10,000. If the M of the A polymer block is less than 3,000, the steric repulsion becomes insufficient, and even if the hydroxide mineral is dispersed, it may be easily aggregated. On the other hand, if the Mn of the A polymer block is more than 15,000, the molecular weight is too large. For this reason, when a liquid medium is used as the non-aqueous dispersion medium, the A polymer block may be dissolved to increase the viscosity.

  The molecular weight distribution (PDI) of the A polymer block is 1.5 or less, preferably 1.3 or less. When the PDI of the A polymer block is more than 1.5, a polymer block that is out of the range of the number average molecular weight (Mn) is likely to be included.

[B polymer block]
The B polymer block is a polymer block that adsorbs to a hydroxide mineral containing a structural unit derived from a methacrylic acid monomer having a carboxy group. In the case of an acidic group other than a carboxy group (for example, a sulfonic acid group or a phosphoric acid group), the water resistance of the hydroxide mineral dispersion may decrease. Examples of the methacrylic acid-based monomer having a carboxy group include methacrylic acid; methacrylic acid added with acrylic acid; monomers obtained by ring-opening reaction of several moles of ε-caprolactone using methacrylic acid as an initiation group; Dihydroxy acids such as phthalic acid, cyclohexanedicarboxylic acid, maleic acid, succinic acid, acid anhydrides and acid chlorides thereof are reacted with hydroxyl group-containing methacrylates such as 2-hydroxyethyl and 2-hydroxypropyl methacrylate. Examples thereof include half ester type methacrylates of polyvalent carboxy compounds such as dibasic acid and trimellitic acid; those obtained by reacting glycidyl methacrylate with dibasic acid.

  The acid value of the B polymer block is 100 mgKOH / g or more and 652 mgKOH / g or less. The acid value of the resin is expressed in mg of potassium hydroxide necessary to neutralize 1 g of the resin. The acid value may be a calculated value calculated from the blending ratio of the monomers or an actually measured value. The acid value is measured by acid-base titration using a 0.1% by weight ethanolic potassium hydroxide solution using, for example, a dilution obtained by diluting a resin with toluene or ethanol as a measurement sample and using a phenolphthalein solution as an indicator. Can do. When the acid value of the B polymer block is in the above range, the B polymer block is favorably adsorbed on the hydroxide mineral. When the acid value of the B polymer block is less than 100 mgKOH / g, it is difficult to adsorb to the hydroxide mineral and may be desorbed. Among the methacrylic acid monomers having a carboxy group that can constitute the B polymer block, the compound having the smallest molecular weight is methacrylic acid. When the B polymer block is a homopolymer block of methacrylic acid, the acid value (calculated value) of the B polymer block is “652.7 mgKOH / g”.

  The B polymer block may contain a structural unit (other structural unit) other than the structural unit derived from the methacrylic acid monomer having a carboxy group. As other monomers constituting the structural unit, monomers for constituting the A polymer block are alkyl methacrylate, cycloalkyl methacrylate, alkyl cycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate. , Cycloalkenoxyalkyl methacrylates, and aryloxyalkyl methacrylates.

  The number average molecular weight of the B polymer block is not more than the number average molecular weight of the A polymer block. Further, the number average molecular weight of the B polymer block is preferably half or less of the number average molecular weight of the A polymer block, and more preferably ¼ or less. The number average molecular weight of the B polymer block can be expressed as a value obtained by subtracting the number average molecular weight of the A polymer block from the number average molecular weight of the AB block copolymer. If the number average molecular weight of the B polymer block is too large, excess B polymer block is adsorbed on the hydroxide mineral, and it becomes difficult to finely disperse the hydroxide mineral, or the hydroxide mineral may aggregate.

(Method for producing AB block copolymer)
The AB block copolymer (AB block copolymer of the present invention) used as a filler dispersant in the hydroxide mineral dispersion of the present invention has its number average molecular weight, molecular weight distribution, etc. defined within a specific range. For this reason, it is preferable to produce the AB block copolymer by living radical polymerization because the molecular weight, molecular weight distribution, and the like can be controlled more accurately. More specifically, the method for producing an AB block copolymer of the present invention includes a step (polymerization step) of performing living radical polymerization using the methacrylic acid-based monomer described above in the presence of a polymerization initiating compound and a catalyst. The polymerization initiating compound is at least one of iodine and an iodine compound. The catalyst is at least one compound selected from the group consisting of phosphorus halides, phosphite compounds, phosphinate compounds, imide compounds, phenol compounds, diphenylmethane compounds, and cyclopentadiene compounds.

  Various methods have been proposed for living radical polymerization. For example, a nitroxide method using the dissociation and bonding of amine oxide radicals (Nitroxide mediated polymerization: NMP method); using a heavy metal such as copper, ruthenium, nickel, iron, and a ligand that forms a complex with these heavy metals, halogens Atom transfer radical polymerization (ATRP method), which uses a compound as the starting compound; dithiocarboxylic acid ester or xanthate compound is used as the starting compound, and an addition polymerizable monomer and a radical initiator are used. Reversible addition-fragmentation chain transfer (RAFT method) and MADIX (Macromolecular Design via Interchange of Xanthate); organic tellurium, organic bismuth, organic antimony, antimony halide, organic germanium, Halogenated gel A method of using a heavy metal bromide such as (Degenerative transfer: DT method) and the like.

  However, the conventional methods as described above have a problem in easily and stably obtaining the AB block copolymer used in the hydroxide mineral dispersion of the present invention. For example, in the NMP method, an amine oxide such as a tetramethylpiperidine oxide radical is used, but it is necessary to polymerize under a high temperature condition of 100 ° C. or higher. Further, when a methacrylic acid monomer is used, there is a problem that polymerization does not proceed.

  In addition, the ATRP method requires the use of heavy metals and is a polymerization method involving redox, so that it is necessary to remove oxygen. Furthermore, in the method of polymerizing by forming a complex using an amine compound as a ligand, it is difficult to polymerize an addition-polymerizable monomer having an acid group as it is because formation of the complex is inhibited if an acidic substance is present in the polymerization system. It is. For this reason, it is necessary to polymerize a monomer in which an acid group is protected with a protecting group, and to remove the protecting group after the polymerization. However, the operation is complicated, and it is not easy to introduce the acid group into the polymer block. .

  The RAFT method and the MADIX method require special compounds such as dithiocarboxylic acid esters and xanthate compounds. Since these are sulfur-based compounds, the resulting polymer tends to have an unpleasant sulfur-based odor and may be colored. For this reason, it is necessary to remove an odor and coloring from the obtained polymer. Furthermore, the polymerization of methacrylic acid monomers may not proceed well. In addition, since sulfur esters such as dithiocarboxylic acid esters and xanthate compounds may be decomposed by amino groups, the resulting polymer may have a low molecular weight or generate a sulfur odor.

  In the DT method, it is necessary to use heavy metals as in the ATRP method. For this reason, there is a problem that it is necessary to remove heavy metals from the obtained polymer and to purify waste water containing the generated heavy metals.

  On the other hand, in the method for producing an AB block copolymer of the present invention, it is not necessary to use a heavy metal compound, and thus it is not necessary to purify the obtained polymer. Moreover, even if it does not use a special compound, an AB block copolymer can be easily manufactured only by using a comparatively cheap material. Furthermore, while the polymerization conditions are mild, the polymerization can be performed under the same conditions as in the conventional radical polymerization method. And the monomer which has a carboxy group etc. can be polymerized as it is.

  In the polymerization step, iodine radicals dissociate when heat or light is applied to iodine or iodine compound used as the polymerization initiating compound. When the monomer is inserted in a state in which the iodine radical is dissociated, the iodine radical immediately binds again to the polymer terminal radical and stabilizes, and the polymerization reaction proceeds while preventing the termination reaction.

  Specific examples of the iodine compound include alkyl iodides such as 2-iodo-1-phenylethane and 1-iodo-1-phenylethane; 2-cyano-2-iodopropane, 2-cyano-2-iodobutane, 1 Cyano group-containing iodides such as cyano-1-iodocyclohexane, 2-cyano-2iodo-2,4-dimethylpentane, 2-cyano-2-iodo-4-methoxy-2,4-dimethylpentane, etc. Can be mentioned.

  As these iodine compounds, commercially available products may be used as they are, but those prepared by a conventionally known method can also be used. For example, an iodine compound can be obtained by reacting an azo compound such as azobisisobutyronitrile with iodine. In addition, the iodine compound can be obtained by reacting an organic halide obtained by substituting iodine of the above iodine compound with a halogen atom such as bromine or chlorine with an iodide salt such as quaternary ammonium iodide or sodium iodide and exchanging the halogen. Can be obtained.

  In the polymerization step, a catalyst capable of extracting iodine of the polymerization initiating compound is used together with the polymerization initiating compound. Examples of catalysts include phosphorus compounds such as phosphorus halides, phosphite compounds, and phosphinate compounds; nitrogen compounds such as imide compounds; oxygen compounds such as phenol compounds; diphenylmethane compounds and cyclopentadiene compounds. The following hydrocarbon compounds are used.

  Specific examples of the phosphorus compound include phosphorus triiodide, diethyl phosphite, dibutyl phosphite, ethoxyphenyl phosphinate, and phenylphenoxy phosphinate. Specific examples of the nitrogen compound include succinimide, 2,2-dimethylsuccinimide, maleimide, phthalimide, N-iodosuccinimide, and hydantoin. Specific examples of the oxygen-based compound include phenol, hydroquinone, methoxyhydroquinone, t-butylphenol, catechol, and di-t-butylhydroxytoluene. Specific examples of the hydrocarbon compound include cyclohexadiene and diphenylmethane. The amount of the catalyst used (number of moles) is preferably less than the amount of use of the polymerization initiating compound (number of moles). If the amount of the catalyst used (number of moles) is too large, the polymerization is too controlled and the polymerization may not proceed easily.

  The temperature at the time of living radical polymerization (polymerization temperature) is preferably 30 to 100 ° C. If the polymerization temperature is too high, iodine at the polymerization terminal may be decomposed, and the terminal may not be stable and living polymerization may not be performed. Further, iodine is bonded to the polymerization terminal, and it is preferable that the terminal obtained by dissociating iodine as a radical is stable. When the monomer is an acrylate or vinyl monomer, the terminal is a secondary iodide, which is relatively stable, the iodine radical does not dissociate, the polymerization reaction does not proceed, or the molecular weight distribution may be widened. Although it is possible to dissociate iodine radicals by raising the temperature, it is preferable in terms of environment and energy to perform moderate polymerization in the above temperature range. For this reason, it is preferable to use a tertiary iodide that is easy to generate radicals and is relatively stable.

  In the polymerization step, a polymerization initiator that can generate radicals is usually added. As the polymerization initiator, conventionally known azo initiators and peroxide initiators can be used. Among them, it is preferable to use a polymerization initiator that generates radicals sufficiently within the above polymerization temperature range. Examples of such polymerization initiators include azo initiators such as 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile). The amount of the polymerization initiator used is preferably 0.001 to 0.1 mol times, more preferably 0.002 to 0.05 mol times with respect to the monomer. If the amount of the polymerization initiator used is too small, the polymerization reaction may not proceed sufficiently. On the other hand, if the amount of the polymerization initiator used is too large, a normal radical polymerization reaction that is not a living radical polymerization reaction may proceed as a side reaction.

  Living radical polymerization may be bulk polymerization that does not use an organic solvent, but is preferably solution polymerization that uses an organic solvent. The organic solvent used can be used as it is as a solvent for the filler dispersant. The organic solvent is preferably one that can dissolve components such as a polymerization initiator compound, a catalyst, a monomer component, and a polymerization initiator. The organic solvent used in the living radical polymerization can be removed, and the formed polymer can be taken out as a solid content. The method for taking out the polymer is not particularly limited, and examples thereof include a method of depositing in a poor solvent, filtering and drying; and taking out only the polymer by drying.

  In the case of solution polymerization, the solid content concentration (monomer concentration) of the polymerization solution is preferably 5 to 80% by mass, more preferably 20 to 60% by mass. When the solid content concentration of the polymerization liquid is less than 5% by mass, the polymerization may not be completed. On the other hand, if the solid content concentration of the polymerization liquid is more than 80% by mass or bulk polymerization, the viscosity of the polymerization liquid is too high, so that stirring becomes difficult and the polymerization yield tends to decrease. Living radical polymerization is preferably carried out until the monomer runs out. The polymerization time is preferably 0.5 to 48 hours, and more preferably 1 to 24 hours. The polymerization atmosphere is not particularly limited, and may be an atmosphere in which oxygen exists within a normal range or a nitrogen stream atmosphere. Moreover, the material (monomer etc.) used for superposition | polymerization may use what removed the impurity by distillation, activated carbon treatment, an alumina treatment, etc., and may use a commercial item as it is. Furthermore, polymerization may be performed under light shielding, or polymerization may be performed in a transparent container such as glass.

The molecular weight of the main chain of the resulting AB block copolymer is controlled by adjusting the relationship (molar ratio) between the amount of the methacrylic acid monomer used in the living radical polymerization and the amount of the polymerization initiating compound used. Can do. That is, by appropriately setting the number of moles of the monomer relative to the number of moles of the polymerization initiating compound, an AB block copolymer whose main chain is controlled to an arbitrary molecular weight can be obtained. For example, when 500 mol of a monomer having a molecular weight of 100 is used for 1 mol of the polymerization initiating compound, a polymer having a theoretical molecular weight of “1 × 100 × 500 = 50000” can be obtained. That is, the theoretical molecular weight of the main chain polymer can be calculated by the following formula (1). The above “molecular weight” is a concept including both the number average molecular weight (Mn) and the weight average molecular weight (Mw).
“Theoretical molecular weight of main chain polymer” = “1 mol of polymerization initiating compound” × “molecular weight of monomer” × “number of moles of monomer / number of moles of polymerization initiating compound” (1)

  The polymerization process may be accompanied by bimolecular termination and disproportionation side reactions, and a polymer having a main chain of the above theoretical molecular weight may not be obtained, so that the polymerization proceeds without these side reactions occurring. It is preferable. The polymerization rate may not be 100%. Furthermore, once the polymerization is completed, a polymerization initiating compound or a catalyst may be added, and the remaining monomer may be consumed to complete the polymerization.

(Non-aqueous dispersion medium)
In general, a hydroxide mineral is hydrophilic and therefore easily dispersed in a hydrophilic medium. However, a hydrophobic medium hardly wets the surface and is difficult to disperse. The dispersion medium that is effective in the hydroxide mineral dispersion of the present invention is a non-aqueous dispersion medium in which it is generally difficult to disperse the hydroxide mineral. The non-aqueous dispersion medium used for the hydroxide mineral dispersion of the present invention is an aprotic organic solvent having a solubility in water at 25 ° C. of 20 g / L or less, or a thermoplastic resin. Specific examples of the aprotic organic solvent include hydrocarbon solvents such as hexane, heptane, dodecane, isoparaffin, cyclohexane, naphthenic solvent, ethylbenzene, styrene; alkyl ketones such as methyl ethyl ketone and methyl isobutyl ketone other than acetone; acetic acid Ester solvents such as ethyl, butyl acetate and methyl butyrate; vinyl monomers used for ultraviolet or electron beam curable inks such as butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate and butyl methacrylate; diethyl Examples include ether solvents such as ether; silicone solvents such as dimethylsiloxane.

  A conventionally well-known thermoplastic resin can be used as a thermoplastic resin. Specific examples of the thermoplastic resin include olefin resins that are polymers of hydrocarbon monomers such as polyethylene, polypropylene, polybutene, polyethylene propylene, polystyrene, polycyclodecene, polycyclopentadiene, polyisoprene; polyvinyl chloride, poly Polyvinyl resins such as vinylidene chloride, polytetrafluoroethylene, polymethyl methacrylate, polyvinyl acetate, polyacrylonitrile, polyacrylamide, and polychloroprene; polyamide resins such as nylon 66, nylon 6, and nylon 12; bisphenol A polycarbonate, etc. Polycarbonate resin; Polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate; From diisocyanate and diol Diisocyanate, a diamine, a polyurethane urea resin comprising a diol; cellulose resins such as triacetyl cellulose; polydimethylsiloxanes, silicone resin such as polyphenyl methyl siloxane may be mentioned polyurethane resins that. A copolymer of polyolefin and polyvinyl may also be used. Examples of such a copolymer include polyethylene vinyl acetate, polyethylene vinyl alcohol, polyethylene ethyl acrylate, and acrylonitrile butadiene styrene polymer.

  Moreover, the oligomer before thermosetting a thermosetting resin can be used as a dispersion medium as needed. Examples of such oligomers include epoxy resin raw materials such as bisphenol A glycidyl ether; unsaturated polyester; natural rubber, butadiene rubber, and silicone rubber before crosslinking (vulcanization).

(Additives, etc.)
In the hydroxide mineral dispersion of the present invention, conventionally known additives may be contained as necessary within a range not impairing the effects of the present invention. Examples of additives that can be used include compatibilizers, antioxidants, light stabilizers, ultraviolet absorbers, leveling agents, lubricants, antifoaming agents, leveling agents, antiseptics, antibacterial agents, perfumes, and antistatic agents. , Conductive agents, antifogging agents, metal powders, dyes, pigments, surfactants, nanofibers, viscosity modifiers, heat transfer agents, magnetic materials, glass powders, natural materials such as clay and wood chips, plasticizers, flame retardants , Infrared absorbers, far-infrared absorbers, heat ray reflectors, sparingly soluble inorganic salts, glass fibers, carbon fibers, and the like.

(Preparation of hydroxide mineral dispersion)
The hydroxide mineral dispersion of the present invention can be prepared by mixing and dispersing each component by a conventionally known method using a disperser or the like. When a liquid medium is used as the non-aqueous dispersion medium, examples of the disperser include kneaders such as a kneader, two rolls, three rolls, and Miracle KCK (trade name, manufactured by Asada Steel); ultrasonic disperser; micro Fluidizer (Mizuho Kogyo Co., Ltd., trade name), Nanomizer (Yoshida Kikai Kogyo Co., trade name), Starburst (Sugino Machine Co., trade name), G-Smasher (Rix Co., trade name) A high pressure homogenizer or the like can be used. Moreover, when using bead media, such as glass and a zircon, a ball mill, a sand mill, a horizontal media mill disperser, a colloid mill, etc. can be used.

  Also, to obtain a mineral hydroxide dispersion with the desired particle size and particle size distribution, reduce the size of the grinding media; increase the filling rate of the grinding media; increase the processing time; slow the discharge speed; It is preferable to employ a technique such as classification using a centrifuge or a centrifuge. The prepared hydroxide mineral dispersion may be used as it is, but it is preferable to remove coarse particles by treating with a centrifuge or passing through a filter. As described above, a hydroxide mineral dispersion in which the non-aqueous dispersion medium is a liquid medium can be obtained.

  The viscosity of the hydroxide mineral dispersion obtained as described above, in which the non-aqueous dispersion medium is a liquid medium, is preferably 1 to 100 mPa · s, more preferably 3 to 20 mPa · s. However, the preferred viscosity differs depending on the amount (concentration) of the hydroxide mineral used and the application of the hydroxide mineral dispersion, and is not particularly limited.

  On the other hand, when a thermoplastic resin is used as the non-aqueous dispersion medium, each component may be kneaded with, for example, a mixing roll, a Banbury mixer, a kneader, a kneader ruder, a single screw extruder, a multi-screw extruder, or the like. The kneading temperature and time are not particularly limited because they vary depending on the type of thermoplastic resin. The hydroxide mineral dispersion in which the non-aqueous dispersion medium is a thermoplastic resin obtained as described above may be cut into a sheet, for example, or pelletized with a pelletizer.

<Organic inorganic composite material>
Next, the organic-inorganic composite material of the present invention will be described. The organic-inorganic composite material of the present invention contains a hydroxide mineral and a polymer. The hydroxide mineral is the same as that used for the above-mentioned hydroxide mineral dispersion, and is selected from the group consisting of magnesium hydroxide, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide. At least one kind selected. The polymer is an AB block copolymer used as a filler dispersant in the above-described hydroxide mineral dispersion.

  The organic-inorganic composite material of the present invention is a composite material (composition) formed by adsorbing a carboxy group of a B polymer block constituting an AB block copolymer to a hydroxide mineral that is an inorganic compound. As described above, the hydroxide mineral dispersion of the present invention can be produced by mixing and dispersing each component such as a hydroxide mineral, a filler dispersant, and a non-aqueous dispersion medium. However, the mineral mineral dispersion is more finely dispersed by dispersing the organic-inorganic composite material prepared beforehand by treating the hydroxide mineral with a filler dispersant (AB block copolymer) in a non-aqueous dispersion medium. The produced hydroxide mineral dispersion can be easily produced. In addition, it is preferable that it is 20-200 mass parts, and, as for content of AB block copolymer with respect to 100 mass parts of hydroxide minerals, it is more preferable that it is 25-100 mass parts.

  The organic-inorganic composite material of the present invention can be produced, for example, by a method of treating a hydroxide mineral by precipitating an AB block copolymer by phase transition or pH conversion. Among them, (i) after obtaining a slurry by dispersing a hydroxide mineral in an aqueous medium in the presence of an alkali neutralized AB block copolymer; (ii) adding an acid to the obtained slurry It is preferable to produce an organic-inorganic composite material by a so-called acid precipitation method in which an AB block copolymer is precipitated.

  Since the AB block copolymer contains a high acid number B polymer block having a carboxy group in its molecular structure, it is dissolved in an aqueous medium by neutralization with an alkali. On the other hand, the A polymer block is insoluble in water. For this reason, when the AB block copolymer is neutralized with an alkali in an aqueous medium, a nano-sized dispersion or emulsion can be obtained. Examples of the alkali used for neutralization include ammonia; organic amines such as triethylamine, diethanolamine, dimethylaminoethanol, and aminomethylpropanol; hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide. . These alkalis may be used in an equimolar amount with the carboxy group in the B polymer block, or in an excess or deficiency. The content (concentration) of the AB block copolymer in the obtained dispersion or emulsion is not particularly limited. Further, the dispersion or emulsion may contain a water-soluble solvent other than water.

  If a hydroxide mineral is dispersed in an aqueous medium in the presence of an alkali neutralized AB block copolymer, a hydroxide mineral slurry can be obtained. The content of the hydroxide mineral in the slurry is preferably 10% by mass or less, and more preferably 5% by mass or less. In obtaining a hydroxide mineral slurry, a conventionally known stirring device or disperser can be used. Further, the mixture may be mixed and stirred using a stirrer, a stirrer with a motor, a high-speed dissolver, or a homomixer, or may be mixed again after being dispersed using a dispersing machine such as a bead mill or a high-pressure homogenizer.

  When the resulting slurry is stirred and an acid is added to deionize the ionized carboxy groups of the AB block copolymer, the AB block copolymer is insolubilized and precipitated, and dispersed in the slurry. Wrapping and covering the hydroxide mineral. Thereby, the target organic-inorganic composite material is formed. Examples of the acid that can be used include inorganic acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, and phosphoric acid; and organic acids such as acetic acid and lactic acid. It is preferable to add the acid diluted with water. When a high concentration acid is added to the slurry, the AB block copolymer may be easily precipitated locally. For this reason, it is preferable to add an aqueous acid solution having a concentration of 10% by mass or less to the slurry. Further, the acid may be added at once, or may be added to the slurry by dropping or spraying. Furthermore, it is preferable to add an acid until the slurry is sufficiently acidic. Specifically, it is preferable to add the acid until the pH of the slurry is 4 or less, and it is more preferable to add the acid until the pH is 3 or less.

  The organic-inorganic composite material deposited in the aqueous medium is filtered and washed as necessary. In order to increase the filtration rate, it is preferable to aggregate the organic-inorganic composite material deposited by heating the slurry. If ions and organic substances are removed by filtration and washing, a water paste of an organic-inorganic composite material can be obtained. The obtained water paste can be used as it is. Moreover, the solidified body obtained by drying a water paste can also be grind | pulverized as needed.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

<Synthesis of polymer (filler dispersant)>
(Synthesis Example 1)
In a 2 L separable flask equipped with a stirrer, a reverse flow condenser, a thermometer, and a nitrogen introduction tube, 385.8 parts of diethylene glycol mono-n-butyl ether (BDG), 5.1 parts of iodine, 2,2′-azobis (4 -Methoxy-2,4-dimethylvaleronitrile) (V-70) 18.5 parts, diphenylmethane (DPM) 0.9 part, and methyl methacrylate (MMA) 250.3 parts are added and heated to 45 ° C. And stirred for 2 hours. Since the brown color of iodine disappeared, it was confirmed that V-70 reacted with iodine and an iodine compound as a polymerization initiating compound was formed. After polymerization at 45 ° C. for 3 hours, a part of the reaction solution was sampled and the solid content was measured and found to be 41.5%. Further, the polymerization rate calculated based on the measured solid content was almost 100%. As described above, a solution of A polymer block was obtained. The number average molecular weight (Mn) of the A polymer block measured by GPC using tetrahydrofuran (THF) as a developing solvent was 5,700, and the molecular weight distribution (PDI) was 1.25. A differential refractive index detector was used as a GPC detector.

After the temperature of the obtained A polymer block solution was lowered to 40 ° C., 43.1 parts of methacrylic acid (MAA), 64.7 parts of MMA, and 3.2 parts of V-70 were added. Polymerization was carried out at 40 ° C. for 4 hours to form a B polymer block, and a solution of AB block copolymer was obtained. The acid value (calculated value) of the B polymer block was 260.5 mgKOH / g. The acid value of the B polymer block was calculated as follows. First, the amount of MAA per part of B polymer block is determined from the following formula.
43.1 / (43.1 + 64.7) = 0.3998 (part)

Next, the MAA molecular weight is 86.1, the KOH molecular weight is 56.1, and the acid value of the B polymer block can be calculated from the following formula.
(0.3998 / 86.1) × 56.1 × 1000 = 260.5 (mgKOH / g)

  The resulting AB block copolymer solution had a solid content of 50.0% and a polymerization rate of almost 100%. The AB block copolymer had an Mn of 8,300, a PDI of 1.29, and a peak top molecular weight of 10,700. It is considered that an AB block copolymer was formed due to an increase in Mn. The Mn of the B polymer block was calculated to be 2,600 because it was a value obtained by subtracting the Mn of the A polymer block from the Mn of the AB block copolymer. After the AB block copolymer obtained with toluene and ethanol was diluted, acid-base titration using a 0.1% ethanolic potassium hydroxide solution was performed using a phenolphthalein solution as an indicator. As a result, the acid value (actual value) of the AB block copolymer was 78.3 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 33.4 parts of 28% aqueous ammonia and 159.5 parts of ion-exchanged water was added to the obtained AB block copolymer solution. It stirred until it became uniform and the resin solution (MAP-1) containing an AB block copolymer was obtained. The resulting resin solution MAP-1 had a solid content of 40.1%.

(Synthesis Example 2)
In a flask similar to that used in Synthesis Example 1 above, BDG 439.6 parts, 5.1 parts iodine, 18.5 parts V-70, 0.9 parts DPM, 100.1 parts MMA, and cyclohexyl methacrylate (CHMA). ) 252.5 parts was added, heated to 45 ° C. and stirred for 2 hours. After polymerization at 45 ° C. for 5 hours, a part of the reaction solution was sampled and the solid content was measured to find 46.0%. Further, the polymerization rate calculated based on the measured solid content was almost 100%. As described above, a solution of A polymer block was obtained. The M of the A polymer block was 8,800, and the PDI was 1.26.

  After the temperature of the obtained A polymer block solution was lowered to 40 ° C., 43.1 parts of MAA, 17.6 parts of benzyl methacrylate (BzMA), and 1.8 parts of V-70 were added. Polymerization was carried out at 40 ° C. for 4 hours to form a B polymer block, and a solution of an AB block copolymer was obtained. The acid value (calculated value) of the B polymer block was 462.6 mgKOH / g. The resulting AB block copolymer solution had a solid content of 49.9% and a polymerization rate of almost 100%. The AB block copolymer had an Mn of 11,500, a PDI of 1.33, and a peak top molecular weight of 15,300. The Mn of the B polymer block was calculated to be 2,700. The acid value (actual value) of the AB block copolymer was 67.8 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 33.4 parts of 28% aqueous ammonia and 186.4 parts of ion-exchanged water was added to the resulting AB block copolymer solution. The mixture was stirred until uniform to obtain a resin solution (MAP-2) containing an AB block copolymer. The solid content of the obtained resin solution MAP-2 was 40.0%.

(Synthesis Example 3)
In a flask similar to that used in Synthesis Example 1 above, BDG 655.5 parts, 5.1 parts iodine, 18.5 parts V-70, 0.9 parts DPM, 352.4 parts BzMA, butyl methacrylate (BMA) 71.1 parts and 74.4 parts of 2-ethylhexyl methacrylate (EHMA) were put, and it heated and stirred at 45 degreeC. After polymerization at 45 ° C. for 5 hours, a part of the reaction solution was sampled and the solid content was measured to find 44.1%. Further, the polymerization rate calculated based on the measured solid content was almost 100%. As described above, a solution of A polymer block was obtained. Mn of A polymer block was 13,500, and PDI was 1.31.

  After the temperature of the obtained A polymer block solution was lowered to 40 ° C., 129.2 parts of MAA and 3.9 parts of V-70 were added. Polymerization was carried out at 40 ° C. for 4 hours to form a B polymer block, and a solution of an AB block copolymer was obtained. The acid value (calculated value) of the B polymer block was 651.6 mgKOH / g. The resulting AB block copolymer solution had a solid content of 40.0% and a polymerization rate of almost 100%. The AB block copolymer had an Mn of 16,000, a PDI of 1.43, and a peak top molecular weight of 21,300. The Mn of the B polymer block was calculated to be 2,500. The acid value (actual value) of the AB block copolymer was 134.5 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 100.2 parts of 28% aqueous ammonia and 227.6 parts of ion-exchanged water was added to the resulting AB block copolymer solution. It stirred until it became uniform and the resin solution (MAP-3) containing an AB block copolymer was obtained. The solid content of the obtained resin solution MAP-3 was 39.9%.

(Synthesis Example 4)
In a flask similar to that used in Synthesis Example 1 above, 490.7 parts of BDG, 5.1 parts of iodine, 18.5 parts of V-70, 0.9 parts of DPM, dicyclopentenyloxyethyl methacrylate (product name “FA -512M "(FA-512M), manufactured by Hitachi Chemical Co., Ltd.) 393.0 parts was added, and the mixture was heated to 45 ° C and stirred. After polymerization at 45 ° C. for 5 hours, a part of the reaction solution was sampled and the solid content was measured, and it was 45.9%. Further, the polymerization rate calculated based on the measured solid content was almost 100%. As described above, a solution of A polymer block was obtained. The A polymer block had a Mn of 9,700 and a PDI of 1.28.

  After the temperature of the obtained A polymer block solution was lowered to 40 ° C., 71.1 parts of MAA and 2.1 parts of V-70 were added. Polymerization was carried out at 40 ° C. for 4 hours to form a B polymer block, and a solution of an AB block copolymer was obtained. The acid value (calculated value) of the B polymer block was 651.6 mgKOH / g. The resulting AB block copolymer solution had a solid content of 49.8% and a polymerization rate of almost 100%. The AB block copolymer had an Mn of 10,800, a PDI of 1.32, and a peak top molecular weight of 14,300. The Mn of the B polymer block was calculated to be 1,100. The acid value (actual value) of the AB block copolymer was 99.6 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 55.2 parts of 28% aqueous ammonia and 190.2 parts of ion-exchanged water was added to the resulting AB block copolymer solution. The mixture was stirred until uniform to obtain a resin solution (MAP-4) containing an AB block copolymer. The solid content of the obtained resin solution MAP-4 was 40.2%.

(Synthesis Example 5)
In a flask similar to that used in Synthesis Example 1 above, 578.1 parts BDG, 5.1 parts iodine, 18.5 parts V-70, 0.9 parts DPM, and 338.6 parts stearyl methacrylate (SMA). And heated to 45 ° C. and stirred. After polymerization at 45 ° C. for 5 hours, a part of the reaction solution was sampled and the solid content was measured and found to be 37.5%. Further, the polymerization rate calculated based on the measured solid content was almost 100%. As described above, a solution of A polymer block was obtained. The A polymer block had an Mn of 8,400 and a PDI of 1.21.

  After the temperature of the obtained A polymer block solution was lowered to 40 ° C., 208.7 parts of 2-methacryloyloxyethylphthalic acid (PAMA) and 6.3 parts of V-70 were added. Polymerization was carried out at 40 ° C. for 4 hours to form a B polymer block, and a solution of an AB block copolymer was obtained. The acid value (calculated value) of the B polymer block was 201.6 mgKOH / g. The resulting AB block copolymer solution had a solid content of 49.8% and a polymerization rate of almost 100%. The AB block copolymer had an Mn of 13,500, a PDI of 1.27, and a peak top molecular weight of 17,100. The Mn of the B polymer block was calculated to be 5,100. The acid value (actual value) of the AB block copolymer was 76.7 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 50.1 parts of 28% aqueous ammonia and 239.0 parts of ion-exchanged water was added to the resulting AB block copolymer solution. The mixture was stirred until uniform to obtain a resin solution (MAP-5) containing an AB block copolymer. The solid content of the obtained resin solution MAP-5 was 40.2%.

(Comparative Synthesis Example 1)
455.1 parts of BDG was placed in the same flask as that used in Synthesis Example 1 and heated to 70 ° C. Monomer containing 250.3 parts of MMA in which 10 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) (V-65) dissolved in a separate container and 43.1 parts of MAA were dissolved The solution was added dropwise to the flask over 1.5 hours. After completion of the dropping, polymerization was further performed at 70 ° C. for 5 hours to obtain a polymer solution. The polymer solution obtained had a solid content of 40.3%. The polymer Mn in the polymer solution was 9,300, the PDI was 2.03, and the acid value (actual value) was 95.8 mgKOH / g.

  An aqueous ammonia solution obtained by mixing 33.4 parts of 28% aqueous ammonia and 229.4 parts of ion-exchanged water was added to the resulting polymer solution. It stirred until it became uniform and the resin solution (RM-1) containing a polymer was obtained. The obtained resin solution RM-1 had a solid content of 30.0%.

  Table 1 summarizes the composition and physical properties of the filler dispersants (polymers) obtained in Synthesis Examples 1 to 5.

<Preparation of organic-inorganic composite material>
( Reference Example 1)
In a 3 L beaker, 100 parts of aluminum hydroxide oxide (trade name “DISPERAL”, manufactured by SASOL, number average particle diameter 10 nm) and 1,750 parts of ion-exchanged water were stirred and mixed using a dissolver. Next, 99.8 parts of MAP-1 prepared in Synthesis Example 1 was added and mixed well at 2,000 rpm for 30 minutes to obtain an aluminum hydroxide oxide slurry. The resulting slurry had a pH of 8.3. Thereafter, 50.2 parts of a 10% aqueous acetic acid solution (1.5 times the acid value of the AB block copolymer in MAP-1) was added. It was confirmed that the whole slurry was remarkably thickened during the addition of the acetic acid aqueous solution, and aluminum hydroxide oxide was precipitated together with the resin. The pH of the thickened slurry after addition of the acetic acid aqueous solution was 4.6. The thickened slurry was heated in a water bath to adjust the internal temperature to 70 ° C. and maintained for 30 minutes to sufficiently aggregate the precipitate. After filtering with Nutsche, the resin-treated aluminum hydroxide oxide paste was obtained by washing 3 times with 1 L of ion exchange water. The paste obtained using a dryer was dried at 80 ° C. for 24 hours, then pulverized with a pulverizer, passed through 50 mesh to remove coarse particles, and an organic-inorganic composite material (VA-1) was obtained.

( Reference Examples 2 to 5, Comparative Examples 1 and 2)
An organic-inorganic composite material was prepared in the same manner as in Reference Example 1 except that the formulation shown in Table 3 was used. In Table 3, the numbers in parentheses of the hydroxide mineral indicate the number average particle diameter (nm).

<Preparation of Hydroxide Mineral Dispersion-1>
(Examples 6 to 11 and Comparative Example 3)
Each component of the kind and amount (parts) shown in Table 4 was blended and stirred for 2 hours using a dissolver. After confirming that there was no lump of hydroxide mineral, dispersion treatment was performed using a horizontal media disperser to obtain a hydroxide mineral dispersion. The meanings of the abbreviations in Table 4 are shown below.
PGMAc: Propylene glycol monomethyl ether (water solubility (25 ° C.): 16 g / L)
Isopar M: Isoparaffin hydrocarbon (manufactured by ExxonMobil, water solubility (25 ° C.): 1 g / L or less)
MMA: Methyl methacrylate (water solubility: 1 g / L or less)

<Evaluation of Hydroxide Mineral Dispersion-1>
Table 5 shows the measurement results of the number average particle size of the hydroxide mineral in the prepared hydroxide mineral dispersion. Further, Table 5 shows the measurement results of the initial viscosity of the hydroxide mineral dispersion and the viscosity (viscosity after storage) after the hydroxide mineral dispersion was left at 45 ° C. for 1 day. In addition, the viscosity of the hydroxide mineral dispersion was measured using an E-type viscometer under the conditions of 60 rpm and 25 ° C.

  As shown in Table 5, it was found that the number average particle size of the hydroxide mineral in the hydroxide mineral dispersions of Examples 6 to 11 was in the range of 84 to 120 nm, and the hydroxide mineral was finely dispersed. . Moreover, the initial viscosity of these hydroxide mineral dispersions was 10 mPa · s or less. Furthermore, when the initial viscosity and the viscosity after storage were compared, it was found that there was almost no change in viscosity and the initial viscosity was maintained. From the above, it is clear that the hydroxide mineral dispersions of Examples 6 to 11 have excellent dispersion stability.

  On the other hand, the hydroxide mineral dispersion of Comparative Example 3 had a high initial viscosity and almost no fluidity, so the viscosity could not be measured. That is, it was found that the dispersibility of the hydroxide mineral dispersion of Comparative Example 3 was insufficient. This is because the adsorption power of the polymer to the hydroxide mineral was weak because the hydroxide mineral was treated with a polymer having a random structure (Comparative Synthesis Example 1) in which adsorption portions to the hydroxide mineral were scattered throughout. it is conceivable that.

<Preparation of filler dispersant (resin powder)>
( Reference Example 12)
In a 3 L beaker, 249.4 parts of MAP-1 prepared in Synthesis Example 1 and 1,750.6 parts of ion-exchanged water were mixed and stirred using a dissolver to obtain an aqueous solution having a solid content of 5%. The pH of the obtained aqueous solution was 8.6. 125.6 parts of 10% aqueous acetic acid solution was added to this aqueous solution to obtain a resin slurry. In addition, it was confirmed that the entire slurry remarkably thickened during the addition of the acetic acid aqueous solution, and the resin was precipitated. The pH of the obtained resin slurry was 4.7. The resin slurry was heated in a water bath to set the internal temperature to 70 ° C. and maintained for 30 minutes to sufficiently agglomerate the deposited resin. After filtration with Nutsche, the resin paste was obtained by washing 3 times with 1 L of ion exchange water. The obtained resin paste was dried at 80 ° C. for 24 hours to obtain Resin Powder-1.

  A stirrer chip, 30 parts of resin powder-1 and 70 parts of PGMAc were placed in a 200 mL beaker and stirred to obtain a PGMAc solution (PM-1) of resin powder-1. The solid content of the obtained PM-1 was 30.0%. Further, a stirrer chip, 30 parts of resin powder-1 and 70 parts of MMA were placed in a 200 mL beaker and stirred to obtain an MMA solution (PM-2) of resin powder-1. The solid content of the obtained PM-2 was 29.9%.

<Preparation of Hydroxide Mineral Dispersion-2>
(Examples 13 and 14)
Each component of the kind and amount (part) shown in Table 6 was blended and stirred for 2 hours using a dissolver. After confirming that there was no lump of hydroxide mineral, dispersion treatment was performed using a horizontal media disperser to obtain a hydroxide mineral dispersion.

(Evaluation of Hydroxide Mineral Dispersion-2)
Table 7 shows the measurement results of the number average particle diameter of the hydroxide mineral in the prepared hydroxide mineral dispersion. Table 7 shows the measurement results of the initial viscosity of the hydroxide mineral dispersion and the viscosity (viscosity after storage) after the hydroxide mineral dispersion was left at 45 ° C. for 1 day. In addition, the viscosity of the hydroxide mineral dispersion was measured using an E-type viscometer under the conditions of 60 rpm and 25 ° C.

  As shown in Table 7, the number average particle size of the hydroxide mineral in the hydroxide mineral dispersions of Examples 13 and 14 was in the range of 85 to 90 nm, and it was found that the hydroxide mineral was finely dispersed. . Moreover, the initial viscosity of these hydroxide mineral dispersions was 10 mPa · s or less. Furthermore, when the initial viscosity and the viscosity after storage were compared, it was found that there was almost no change in viscosity and the initial viscosity was maintained. As described above, according to the filler dispersant of the present invention, the hydroxide mineral is excellent in dispersion stability even when it is used directly as a dispersant without preparing the organic-inorganic composite material by treating the hydroxide mineral. It is clear that dispersions can be prepared.

<Application to resin kneading>
(Application 1)
10 parts of VA-1 obtained in Reference Example 1 and 132.8 parts of pellets of methyl methacrylate resin (specific gravity 1.5, MFR 2 g / min) were mixed, and then sufficiently melt mixed at 250 ° C. using a small kneader. did. Subsequently, after extruding using a twin screw extruder, granulation was performed to obtain pellets containing 5% of aluminum hydroxide oxide. Using a laboratory molding machine, a plate was prepared using the obtained pellets. When the surface and cross section of the prepared plate were cut thinly and observed with an electron microscope, it was confirmed that the aluminum hydroxide oxide was uniformly dispersed.

(Application example 2)
10 parts of VC-1 obtained in Reference Example 4 and 233.3 parts of low density polyethylene (specific gravity 0.918, MFR 12 g / min) were processed using a twin screw extruder (Nippon Steel Works, TEX 30 mm). The mixture was melt-kneaded at a temperature of 180 ° C. and granulated to obtain pellets. Using an inflation molding machine, a film sheet containing 2.0% calcium hydroxide was molded using the obtained pellets. This film sheet was pressed with a press machine to produce a sheet having a thickness of about 20 μm. When the produced sheet was observed with an optical microscope, no aggregate of calcium hydroxide was observed, and it was confirmed that the sheet was uniformly dispersed.

(Application 3)
Except that VA-2 obtained in Reference Example 5 was used, a film sheet containing 2.0% aluminum hydroxide oxide was molded and a sheet having a thickness of about 20 μm, in the same manner as Application Example 2 described above. Was made. When the produced sheet was observed with an optical microscope, no aggregates of aluminum hydroxide oxide were observed, and it was confirmed that the sheets were uniformly dispersed.

  From the results of Application Examples 1 to 3, the filler dispersant of the present invention clearly separates the adsorbed portion on the hydroxide mineral and the site compatible with the non-aqueous dispersion medium, and each function is sufficiently exhibited. As a result, it was found that excellent dispersibility was exhibited even in the resin.

(Comparative Application Example 1)
A film sheet containing 2.0% calcium hydroxide was molded and a sheet having a thickness of about 20 μm was formed in the same manner as in Application Example 2 except that RVC-1 obtained in Comparative Example 2 was used. Produced. When the produced sheet was observed with an optical microscope, many aggregates of about 50 μm were observed. This is because the adsorption power of the polymer to calcium hydroxide was weak because calcium hydroxide was treated with a polymer (RM-1) having a random structure in which adsorption portions to the hydroxide mineral were scattered throughout. Conceivable.

<Application to resin molding by bulk polymerization>
(Application 4)
While flowing nitrogen gas through the reaction vessel, 49.5 parts of DA-3 obtained in Example 11 and 0.5 part of V-65 were added. Bulk polymerization was performed at 70 ° C. for 5 hours to obtain a polymethyl methacrylate (PMMA) molded product having a size of about 1.5 cm square. No cracks were generated in the obtained molded body even when volume shrinkage caused by polymerization occurred. Further, the polymerization proceeded without breaking the dispersion, and no aggregation occurred in the middle.

  The hydroxide mineral dispersion and the organic-inorganic composite material of the present invention are excellent in dispersibility, dispersion stability, and fillability, as well as flame retardancy, thermal conductivity, transparency, insulation, mechanical properties, and optics. Characteristics such as characteristics can be imparted to the resin or the like. For this reason, the hydroxide mineral dispersion of the present invention includes, for example, automobile members; housings for electrical appliances such as televisions, telephones and watches; housings for mobile communication devices such as mobile phones; printing equipment, copiers, and sports equipment. It is useful as a structural material such as a casing, a material for paints, inks, coating agents, and ultraviolet curable inks, and can also be used for building materials.

Claims (3)

A hydroxide mineral dispersion containing a hydroxide mineral, a non-aqueous dispersion medium, and a filler dispersant for dispersing the hydroxide mineral in the non-aqueous dispersion medium,
The hydroxide mineral is at least one selected from the group consisting of magnesium hydroxide, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide;
The filler dispersant contains 90% by mass or more of a structural unit derived from a methacrylic acid monomer, has a number average molecular weight of 4,000 to 20,000, and a molecular weight distribution (weight average molecular weight / number average). An AB block copolymer comprising an A polymer block and a B polymer block having a molecular weight of 1.6 or less,
The A polymer block is selected from the group consisting of alkyl methacrylate, cycloalkyl methacrylate, alkyl cycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate, cycloalkenyloxyalkyl methacrylate, and aryloxyalkyl methacrylate. While containing 80% by mass or more of structural units derived from at least one selected, the number average molecular weight is 3,000 or more and 15,000 or less, and the molecular weight distribution (weight average molecular weight / number average molecular weight) is 1. 5 or less,
The B polymer block contains a structural unit derived from a methacrylic acid monomer having a carboxy group, has an acid value of 100 mgKOH / g or more and 652 mgKOH / g or less, and has a number average molecular weight of the number of the A polymer block. Below the average molecular weight,
A hydroxide mineral dispersion in which the non-aqueous dispersion medium is an aprotic organic solvent having a solubility in water at 25 ° C. of 20 g / L or less, or a thermoplastic resin. The content of the hydroxide mineral is 5 to 50% by mass,
The number average particle size of the hydroxide mineral is 500 nm or less,
2. The hydroxide mineral dispersion according to claim 1, wherein a content of the filler dispersant is 20 to 200 parts by mass with respect to 100 parts by mass of the hydroxide mineral. A method for producing a hydroxide mineral dispersion according to claim 1 or 2 ,
The organic-inorganic composite material, have a step of dispersing in the nonaqueous dispersing medium,
The organic-inorganic composite material contains a hydroxide mineral and a polymer,
The hydroxide mineral is at least one selected from the group consisting of magnesium hydroxide, calcium hydroxide, aluminum hydroxide oxide, aluminum hydroxide, iron oxide hydroxide, and iron hydroxide;
The polymer contains 90% by mass or more of a structural unit derived from a methacrylic acid monomer, has a number average molecular weight of 4,000 to 20,000, and a molecular weight distribution (weight average molecular weight / number average molecular weight). Is an AB block copolymer comprising an A polymer block and a B polymer block, wherein
The A polymer block is selected from the group consisting of alkyl methacrylate, cycloalkyl methacrylate, alkyl cycloalkyl methacrylate, aryl methacrylate, arylalkyl methacrylate, alkoxyalkyl methacrylate, cycloalkoxyalkyl methacrylate, cycloalkenyloxyalkyl methacrylate, and aryloxyalkyl methacrylate. While containing 80% by mass or more of structural units derived from at least one selected, the number average molecular weight is 3,000 or more and 15,000 or less, and the molecular weight distribution (weight average molecular weight / number average molecular weight) is 1. 5 or less,
The B polymer block contains a structural unit derived from a methacrylic acid monomer having a carboxy group, has an acid value of 100 mgKOH / g or more and 652 mgKOH / g or less, and has a number average molecular weight of the number of the A polymer block. method for producing a Ru der average molecular weight of less hydroxide mineral dispersion.