JP2007161506A - Method for manufacturing manganese dioxide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxidizing agent (particularly manganese dioxide) for a hardening agent of a polysulfide polymer, the agent capable of hardening a polysulfide polymer and giving a hardened product with less expansion or reduction in strength even when the product is immersed in hot water for a long period of time. <P>SOLUTION: The method for manufacturing manganese dioxide is characterized in that manganese dioxide is treated in an acid aqueous solution of 1 N or more concentration at 60°C or higher. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing manganese dioxide that is suitably used as a curing agent for polysulfide polymers.

  Manganese dioxide has long been used as an oxidizing agent for curing polysulfide polymers. Manganese dioxide is activated by treatment in an aqueous sodium hydroxide solution at high temperature and pressure. When activated manganese dioxide is used as a curing agent for polysulfide polymers, the curing rate is increased. In particular, manganese dioxide treated with a high-concentration sodium hydroxide aqueous solution has a high curing rate, and even when the curing agent is stored for a long period of time, the curing rate does not become slow and the storage stability is good. Since the cured product has extremely high weather resistance, oil resistance, and adhesion to metal, it is widely used mainly as a sealing material (see Patent Document 1).

However, manganese dioxide treated with a high-concentration sodium hydroxide aqueous solution contains many alkali components, and when a cured product cured with such manganese dioxide is immersed in hot water at about 80 ° C. for a long time, The water resistance may not be sufficient because it may swell or the strength may decrease.
Japanese Laid-Open Patent Publication No. 9-2117008

  An object of the present invention is to provide a method for producing manganese dioxide, which is obtained by curing a polysulfide polymer, and the obtained cured product has little swelling and a decrease in strength even when immersed in hot water for a long period of time.

  According to the present invention, manganese dioxide treated at a temperature of 60 ° C. or higher in an aqueous acid solution having a concentration of 1 N or higher cures the polysulfide polymer, and the resulting cured product is heated to about 80 ° C. for a long time. There is little swelling and loss of strength even when immersed.

  As a result of diligent research in view of the above-mentioned object, the present inventors cured manganese sulfide treated at a temperature of 60 ° C. or higher in an acid aqueous solution having a concentration of 1 N or higher, and the cured product obtained was It has been found that even if it is immersed in hot water at about 80 ° C. for a long period of time, it does not swell and its strength is not lowered, and the present invention has been achieved.

  Hereinafter, the present invention will be described in detail.

  As the manganese dioxide used in the present invention, natural manganese dioxide or chemically synthesized manganese dioxide can be used. Examples of natural manganese dioxide ore include soft manganese ore, permanganate or hard manganese ore. Manganese dioxide by chemical synthesis includes products obtained by electrolyzing a manganese sulfate solution, products obtained by heating manganese oxide in the presence of oxygen in a furnace, products obtained by heating manganese nitrate, etc. Can be mentioned.

  Furthermore, the manganese dioxide used in the present invention can use manganese dioxide containing an alkali metal, an alkaline earth metal, a transition metal, aluminum, silicon and ions thereof, and compounds thereof in order to increase the curing rate. Specifically, examples of the alkali metal include lithium, sodium, potassium, rubidium, and cesium. Examples of the alkaline earth metal include magnesium, calcium, strontium, and barium. Examples of the transition metal include chromium, cobalt, nickel, and copper. As the compound, oxide, hydroxide, etc. are used. Specifically, lithium oxide, lithium hydroxide, sodium oxide, sodium hydroxide, potassium oxide, potassium hydroxide, rubidium oxide, rubidium hydroxide, cesium oxide, water Cesium oxide, magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, strontium oxide, strontium hydroxide, barium oxide, barium hydroxide, chromium oxide (II), chromium oxide (III), chromium oxide (VI), water Chromium oxide (II), chromium hydroxide (III), cobalt oxide, cobalt hydroxide oxide (II), dicobalt tetroxide monocobalt (II), cobalt hydroxide, nickel oxide (II), nickel hydroxide (II) , Copper oxide (I), copper oxide (II), copper hydroxide (III), aluminum oxide Beam, aluminum hydroxide, silicon monoxide, silicon dioxide, and the like. The content of alkali metal, alkaline earth metal, transition metal, aluminum, silicon and ions thereof, and compounds thereof is preferably 0.1 to 20% by mass, more preferably 1 to 10% by mass. If it is less than 0.1% by mass, the effect of improving the curing rate may not be obtained. If it exceeds 20% by mass, the resulting cured product will be undesirably increased in swelling. Two or more kinds of alkali metals, alkaline earth metals, transition metals, aluminum, silicon and ions thereof, and compounds thereof may be added.

  As the acid used in the present invention, various mineral acids, organic acids and aqueous solutions thereof can be used. As the mineral acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrobromic acid, hydrofluoric acid and the like can be used. As the organic acid, acetic acid, oxalic acid, butyric acid, benzoic acid, yoshiphatic acid, monochloroacetic acid, trifluoroacetic acid and the like can be used. Of these, nitric acid and sulfuric acid are preferred because of their high treatment effect.

  The concentration of the acid used in the present invention is 1 N or more. If it is less than 1 standard, the effect of treatment cannot be obtained sufficiently. The concentration of the acid used in the present invention is preferably 1 N or more and 16 N or less, more preferably 2 N or more and 12 N or less.

    The amount of acid relative to manganese dioxide is not particularly limited, but is preferably 5 to 200 times that of manganese dioxide on a volume basis. When the amount is less than 5 times, the effect of the treatment may not be sufficiently obtained, and when the amount is 200 times or more, the productivity may be deteriorated. The amount of acid relative to manganese dioxide is particularly preferably 5 to 100 times.

    As a method for treating manganese dioxide with an acid, an immersion treatment in which manganese dioxide is added to the acid, a treatment in which an acid is passed through a filler of manganese dioxide, or the like can be used. When immersion treatment is used, the treatment effect can be enhanced by shaking and stirring the liquid. Processing temperature is 60 degreeC or more. The treatment temperature is preferably 60 ° C to 140 ° C, more preferably 80 ° C to 120 ° C. Moreover, the process of 100 degreeC or more can also be performed in a pressure-resistant container. The treatment time usually varies depending on the treatment temperature, but is preferably 30 minutes to 24 hours, particularly preferably 1 to 6 hours.

    After treating manganese dioxide with an acid, the acid is typically removed. The acid is removed using a treatment liquid after filtration. As the treatment liquid, water, an aqueous solution of alcohols or an aqueous solution of ketones can be used alone or in combination. Methanol or ethanol can be used as alcohols, and acetone or the like can be used as ketones.

    The treated manganese dioxide can be dried to remove moisture as necessary. Drying is preferably performed at 50 to 150 ° C, more preferably 70 to 100 ° C. After drying, it may be crushed as necessary.

  Manganese dioxide is obtained by the above production method. The obtained manganese dioxide is used for dry batteries, ferrite, match raw materials, glass industry (coloring and decoloring), bleaching powder raw materials, manganese-containing copper, oxygen gas, manganese compound manufacturing pharmaceuticals, fireworks, special alloys, enameled iron wires (dark black, black and black Metallic luster), rubber tackifier, electrolysis (zinc and copper surfaces), fabrics, fertilizers, paints (linoleum or resin, various drying oils, pigment desiccants), dyes (purine production from alizarin, blood cells), It can be used as an intermediate (production of oxidizing agent, hydroquinone, production of benzaldehyde and benzoic acid from toluene), acetylene detergent, enamel, water removal, glaze, denitration catalyst, and oxidizing agent. In particular, when used as an oxidizing agent for polysulfide polymers, it has excellent characteristics.

When the manganese dioxide of the present invention is used as an oxidizing agent for a polysulfide polymer, it is advantageous for improving the economic efficiency, workability when applying the composition, and physical properties after curing, calcium carbonate, talc, clay, titanium oxide, silica. , Zeolite, perlite, ceramic balloon, glass balloon, silica balloon, shirasu balloon, alumina balloon, filler such as hollow microspheres such as plastic balloon, phthalate ester, butylbenzyl phthalate, chlorinated paraffin, hydrogenated terphenyl, A plasticizer such as a xylene resin described in JP-A-10-60261, an acrylate copolymer described in Japanese Patent Application No. 2002-327747, a hydrocarbon plasticizer described in Japanese Patent Application No. 2002-214958, and JP-A 2000-344853 Fatty acid ester described in JP UV absorbers described in JP 001-64504, -S in one molecule described in JP 2001-220423 _x - (where, x is an integer of 2 or more) can be an organic polysulfide compound having only one.

  The xylene resin is a pale yellow transparent water tank-like resin obtained by reacting xylene or mesitylene and formalin in the presence of a strong acid catalyst. Xylene is a raw material that is a xylene formaldehyde resin, and has three isomers of xylene. Of these, meta-xylene is the most reactive. Also, mesitylene formaldehyde resin is obtained by using mesitylene as a starting material. The viscosity and composition of these resins can be adjusted by changing the molar ratio of xylene or mesitylene and formalin. The obtained resin has a polymolecular structure in which the xylene nucleus or mesitylene nucleus is mainly linked by a methylene, acetal or ether bond, and the terminal has a xylene nucleus or mesitylene nucleus and some methylol groups or methoxymethyl groups. It is an oligomer having a number average molecular weight of about 250 to 700.

  The acrylic ester copolymer is a yellow transparent water-like resin obtained by polymerizing various acrylic ester monomers, and the acrylic ester monomers include methyl acrylate, ethyl acrylate, acrylic acid. Propyl, isopropyl acrylate, butyl acrylate, isobutyl acrylate, s-butyl acrylate, t-butyl acrylate, neopentyl acrylate, 2-ethylhexyl acrylate, isodecyl acrylate, lauryl acrylate, tridecyl acrylate and acrylic acid Examples include stearyl, cyclohexyl acrylate, isobornyl acrylate, tricyclodecynyl acrylate, 2-methoxyethyl acrylate, phenoxyethyl acrylate, and the like. It is an oligomer having a number average molecular weight of about 500 to 2500. The monomer can be used not only alone but also two or more simultaneously.

  Examples of the hydrocarbon plasticizer include diarylalkane type compounds such as JP-B-56-14705, JP-B-56-15440, JP-B-57-56511, and the like, and triaryl dialkanes. High boiling point aromatic hydrocarbons (trade name “Nisseki Hysol SAS-LH” manufactured by Nippon Petrochemical Co., Ltd.) consisting of a reaction product of a compound of the type, a styrene 2-3 polymer and an alkylbenzene. Hydrocarbon plasticizers are preferred because of their low hygroscopicity and good gas barrier properties.

  As the fatty acid ester, a wax composed of a fatty acid and a monovalent or divalent alcohol, or a fatty acid glycerin ester (hereinafter referred to as fatty acid glyceride) composed of a fatty acid and glycerin can be used, and the acid group is a saturated fatty acid and / or unsaturated. Fatty acids may be used. Saturated fatty acids include butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, melicic acid, Saturated fatty acids include succinic acid, lindelic acid, tzuic acid, succinic acid, myristoleic acid, zomarinic acid, petrothelic acid, oleic acid, vaccenic acid, gadoleic acid, whale oil acid, erucic acid, shark oil acid, linoleic acid, Examples include hiragoic acid, eleostearic acid, bunic acid, tricosanoic acid, linolenic acid, moloctic acid, parinaric acid, arachidonic acid, sardine acid, hiragasic acid, and nisic acid.

  Of the above fatty acid esters, fatty acid glycerides are particularly preferred, and specifically, stearic acid monoglyceride, stearic acid monodiglyceride whose acid group is a saturated fatty acid, oleic acid monoglyceride, oleic acid monodiglyceride whose acid group is an unsaturated fatty acid, Examples thereof include oleic acid stearic acid monodiglyceride in which these acid groups are mixed.

  Examples of the ultraviolet absorber include benzophenone series, benzotriazole series, phenyl salicylate series, triazine series, nickel salt and nickel complex series. Particularly preferred ultraviolet absorbers are benzotriazole-based, nickel salt, and nickel complex-based ultraviolet absorbers, and benzotriazole-based ultraviolet absorbers are particularly preferable. Specifically, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- [2-hydroxy-3 (3,4,5,6-tetra-hydrophthalimidomethyl) -5-methylphenyl] benzo Triazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-4-octylphenyl) benzotriazole, 2- (2-hydroxy-3 , 5-t-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-t-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5-t-octylphenyl) benzotriazole 2- (2-hydroxy-3,5-di-t-amylphenyl) benzotriazole, nickel dibutyldithiocarbamate DOO, [2,2'-thiobis (4-t-octyl phenolate)] - 2-ethylhexylamine - such as nickel and the like.

  Examples of the organic polysulfide compound having only one —Sx— (wherein x is an integer of 2 or more) in one molecule include linear or cyclic compounds having aliphatic and / or aromatic groups. Specifically, dimethyl disulfide, di-t-butyl disulfide, dithiodiglycolic acid, dithiopropionic acid, dithiopropionic acid ester, dithiobenzoic acid, dithiosalicylic acid, di-t-nonyl polysulfide, di-t-dodecyl Examples thereof include polysulfide, diphenyl disulfide, dibenzyl disulfide, lenthionine, and sporidesmin. A particularly preferred example is di-t-dodecyl polysulfide having a low odor.

  Furthermore, an adhesion-imparting agent can be added to the curable composition of the present invention in order to improve the adhesion to a material part such as glass or aluminum after construction.

  Specifically, a silane coupling agent is used. As silane coupling agents, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropylmethoxysilane, γ-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxy Examples thereof include silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-gridoxypropyldimethoxysilane, and γ-gridoxypropylmethyldiethoxysilane. Also, a terminal trimethoxysilane-modified polysulfide polymer synthesized by reacting the polysulfide polymer “thiocol LP-3” described in JP-A-6-271833 with γ-gridoxypropyltrimethoxysilane can be used as a silane coupling agent. Can do. Two or more of these silane coupling agents may be used.

  The invention is illustrated in more detail by the following examples.

Example 1
10 g of manganese dioxide (manganese dioxide (powder) chemical use: manufactured by Junsei) was added to 1 L of 1N sulfuric acid aqueous solution, and the temperature was raised to 100 ° C. with stirring. The mixture was stirred for 2 hours while maintaining the same temperature, cooled to room temperature, and filtered under reduced pressure. Manganese dioxide was produced by washing with distilled water and drying at 70 ° C. for 24 hours.

Example 2
In Example 1, it manufactured like Example 1 except having used 1N nitric acid instead of sulfuric acid aqueous solution.

Comparative Example 1
In Example 1, it manufactured like Example 1 except having used distilled water instead of sulfuric acid aqueous solution.

Comparative Example 2
To 1 L of 1N aqueous nitric acid solution, 10 g of manganese dioxide (manufactured by manganese dioxide (powder) chemical: manufactured by Junsei) was added and allowed to stand at room temperature for 2 days. After filtering by reduced pressure filtration, it was washed with distilled water and dried at 70 ° C. for 24 hours to produce manganese dioxide.

Using the manganese dioxide treated as described above, it was blended according to the formulation shown in Table 1 and mixed. The mixture was molded into a 30 mm × 30 mm sheet having a thickness of 2 mm and cured by heating at 70 ° C. for 24 hours. Using the obtained cured product, the volume swelling ratio in water was measured. The mass of the sheet-like cured product is (A), the mass of the sheet-like cured product in 20 ° C. water is (B) the density (N) of water at 20 ° C.
V = (A−B) / N
Was used to determine the volume (V) of the sheet-like cured product.

  Furthermore, after the sheet-like cured product was immersed in water at 80 ° C. for 10 days, the volume after water aging was similarly determined, and the volume change rate before and after water aging was taken as the volume swelling rate. The results are shown in Table 2.

実施例に記載の二酸化マンガンは長期間熱水に浸しても膨れが小さく良好であった。

Manganese dioxide described in the examples was good even if it was immersed in hot water for a long period of time.

Claims (6)

A method for producing manganese dioxide, comprising treating manganese dioxide in an acid aqueous solution having a concentration of 1 N or higher at a temperature of 60 ° C or higher. The method for producing manganese dioxide according to claim 1, wherein the manganese dioxide contains at least one substance selected from the group consisting of alkali metals, alkaline earth metals, transition metals, aluminum, and silicon. The method for producing manganese dioxide according to claim 1, wherein the manganese dioxide contains at least one compound of an alkali metal, an alkaline earth metal, a transition metal, aluminum, and silicon. 3. The manganese dioxide according to claim 1, wherein the manganese dioxide contains at least one substance selected from alkali metals, alkaline earth metals, transition metals, aluminum, and silicon in an amount of 0.1 to 20 wt% with respect to manganese dioxide. Manufacturing method of manganese dioxide. The manganese dioxide contains at least one compound selected from alkali metal, alkaline earth metal, transition metal, aluminum, and silicon compounds in an amount of 0.1 to 20% by weight based on manganese dioxide. The manufacturing method of manganese dioxide as described. 6. The method for producing manganese dioxide according to claim 1, wherein the acid is sulfuric acid and / or nitric acid.