JPS6321259A - Manufacture of inorganic layer-form porous body - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for producing an inorganic layered porous material having excellent heat insulation properties.

[Background technology]

As a layered compound having voids, there is an intercalation material in which a different substance such as hydroxide is inserted between the layers of a swellable layered compound (for example, Japanese Patent Application Laid-Open No. 54-588
4 and JP-A-54-16386).

However, since this material has a small glabellar distance of 10 Å or less, it is easily affected by adsorbed water, and it cannot be said to have very good heat insulation properties.

In contrast, we used a mixture of smectite minerals and water-soluble polymer compounds as microporous clay materials.
In addition, intercalation of cationic oxide or polymeric silica has been proposed in JP-A-60-1318.
78, JP 60-137812, JP 60-137813, JP 60-155526
No. 60-166217, etc. According to these methods, the interlayer distance can be increased from 10 Å or less in the case of the above-mentioned intercalation material to about 30. However, with this method, as shown in Figure 8, during firing, the gas generated by the decomposition of organic substances in the components intercalated between the eyebrows spreads between the layers, so-called gas bulges 8. and delamination 9 occur, and the layered compound 6'
The strength and appearance of the product may be significantly impaired. Furthermore, since air convection and radiation are likely to occur inside such a gas bulge, there is also the problem that the heat insulation properties are reduced.

[Purpose of the invention]

This invention was made in view of these circumstances, and provides a method for producing an inorganic layered porous material that prevents gas blistering and delamination, has homogeneous micro-porosity, and has excellent heat insulation properties. is intended to provide.

[Disclosure of the invention]

In order to achieve the above object, the present invention swells a swellable layered compound, inserts at least an inorganic pillar among an inorganic pillar and an organic pillar between the layers, and aligns and dries the compound to form a fine structure between the layers. A method for producing an inorganic layered porous material forming voids, the method comprising the step of forming fine holes for degassing in a swellable layered compound after orientation and before drying. The gist is the manufacturing method.

Hereinafter, embodiments of the present invention will be explained in detail with reference to the accompanying drawings.

As shown in FIG. 1, which schematically shows the structure, the inorganic layered porous material A obtained by the method for producing an inorganic layered porous material of the present invention has an inorganic compound 2 inserted between the layers 1.1 of the inorganic layered compound. Fixed. Therefore, the gap 3 between the layers is maintained between 30 and 600 people.

Examples of the swelling layered compound include Na-montmorillonite,
Examples include Ca-montmorillonite, acid clay, 3-octahedral synthetic smectite, Na-hectolite, lj-hectite, Na-teniolite, Li-teniolite, and synthetic mica (Na-fluorine-tetrasilicon mica). It is not limited to these as long as it is a layered compound. When a swellable layered compound such as Ca-montmorillonite or acid clay is used as the main material, it is difficult to swell unless a strong shearing force is applied, so it is necessary to knead it during swelling.

As the inorganic pillar inserted between the layers of the swellable layered compound, metal alcoholate (hereinafter referred to as "metal alcoholate A") is used.
At least one of a colloidal inorganic compound and a polymer obtained by hydrolyzing .

As metal alcoholate 8, S i (OR) 4
, AI(OR) 3 , and Ge(OR) 4 , and these may be used alone or in combination. Such metal alcoholate A becomes a polymer having a metal-#I elementary bond as its main chain through the hydrolysis, which becomes the inorganic pillar.

Examples of the above metal alcoholate A include:
The following compounds are available, but other compounds can also be used.

Si (OCz Hs)4. Si (OCH3)
a.

Although Qe (QC3H7)s, Ge (QC2H5)4゜ colloidal inorganic compounds are not particularly limited,
A thermally stable oxide or one that expands when heated is preferred. Such compounds include, for example,
Sin□, 5b203. Fe2 o,, A1203,
Examples include TiO2 and ZrO2, and these may be used alone or in combination. Although the particle size of such a colloidal inorganic compound is not particularly limited in the present invention, it is preferably about 50 to 150 particles.

The above-mentioned inorganic pillars may be inserted as they are between the layers of the swellable layered compound, but the surface of the inorganic pillars is a cationic inorganic compound and a metal alcoholate other than the metal alcoholate A (hereinafter referred to as "metal alcoholate"). BJ) may be modified and then inserted between the layers.

Cationic inorganic compounds used to modify the surface of the inorganic pillars include titanium compounds, zirconium compounds, and hepheme compounds.

Examples include iron-based compounds, copper-based compounds, chromium-based compounds, nickel-based compounds, zinc-based compounds, aluminum-based compounds, manganese-based compounds, phosphorus-based compounds, boron-based compounds, and the like. Such cationic inorganic compounds include T
Examples include metal chlorides such as i CI 4, metal oxychlorides such as ZrOCl2, or nitrate compounds, but other materials may also be used.

Moreover, as metal alcoholate B used for the same purpose, T i (OR) 4 , Z r (OR
) 4.

Examples include PO(OR)3 and B(OR)3. These may be used alone or in combination.

Examples of the above-mentioned metal alcoholate B include:
Some of the compounds are listed below, but others can also be used.

Ti (QC3 H7)a, Zr (QC3H?
)4, PO(OCH3)4, PO(QC2H5)4
.

B(OCH3)4. B(OC2H5)46 Furthermore, in the present invention, in addition to the above inorganic pillars, at least one of a water-soluble polymer compound and a quaternary ammonium salt is used as an organic pillar, and the layer 1 of the swellable layered compound is formed.
, 1 can also be inserted.

Various water-soluble polymer compounds can be considered, such as polyvinyl alcohol.

Polyethylene glycol, polyethylene oxide, methylcellulose, carboxymethylcellulose, polyacrylic acid, sodium polyacrylate.

Preferred examples include polyvinylpyrrolidone.

Various types of quaternary ammonium salts can be considered, but among them, those having groups such as octadecyl group, hexadecyl group, tetradecyl group, and dodecyl group are preferred. Such quaternary ammonium salts include the following compounds, which help the insertion of the inorganic pillars by expanding the space between the layers, are vaporized by firing and leave a gap between the eyebrows, and have the ability to Other materials may also be used as long as they are compatible.

Octadecyltrimethylammonium salt, dioctadecyldimethylammonium salt, hexadecyltrimethylammonium salt, dioctadecyldimethylammonium salt, tetradecyltrimethylammonium salt, dioctadecyldimethylammonium salt.

Next, the method for manufacturing the inorganic layered porous body of the present invention will be explained in detail based on drawings schematically showing one embodiment thereof.

Substances such as swellable clay minerals, as shown in Figure 2,
It is made up of a collection of swellable layered compounds A1. This compound A1, which is the main material, is mixed with a solvent such as water (kneaded if necessary), and as shown in FIG. A layered compound A2 is obtained. As the solvent, water is used for -a, but other polar solvents such as methanol, DMF, DMSO, etc. may be used alone or in combination.

Next, as the inorganic pillar 21, metal alcohol-1-A
When using a polymer, dissolve metal alcoholate A by adding a solvent such as ethanol or isopropanol,
Water and a reaction catalyst (hydrolysis catalyst) such as hydrochloric acid are added and mixed to cause a hydrolysis reaction. This hydrolysis reaction is preferably carried out at a temperature of about 70°C, although it is not particularly limited. Also, when the hydrolysis reaction of the inorganic pillar 21 has progressed to some extent and the nucleus has grown, metal alcoholate B or a cationic inorganic compound is added to the reaction solution, and these compounds are added to the nucleus. If a colloidal inorganic compound is used as the inorganic pillar 21, it can be used as is. Alternatively, the metal alcoholate B or the cationic inorganic compound may be added to the dispersion of the colloidal inorganic compound, and these compounds may be added to the surface of the inorganic pillar 21 in the same manner as in the previous case. Similarly, the reaction product 21' shown in FIG. 4 is obtained.

The inorganic pillars 21 and reactants 21' thus formed are mixed with the swelling layered compound that has been swollen in advance, and inserted (intercalated) between the layers 1 and 1 of the layered compound. Although the temperature during mixing is not particularly limited in the present invention, it is preferably around 60 to 70'C. A water-soluble polymer compound, a quaternary ammonium salt, or the like may be inserted between these layers as organic pillars 5, if necessary.

In addition, when a water-soluble polymer compound or a quaternary ammonium salt is blended as the organic pillar 5, as shown in FIG. At the same time, it slows down the movement of the inorganic pillars 21 and serves to hold them between the layers 1 and 1.The held inorganic pillars 21 thereby hold the gap between the layers 1 and 1 while being expanded. .Also, this inorganic pillar 21
is a reactant 21' whose surface is modified, as shown in FIG.
It is thought that it is electrically coupled to the negative portion of the surface, thereby making it possible to maintain the gap between the layers 1 and 1 more widely. The swellable layered compound in this state is A3
It is called.

After the reaction solution as described above is dehydrated by a method such as centrifugation or filtration, it is oriented into a plate shape using a spatula or the like (FIG. 6).

Then, as shown in the circle in FIG. 6, a plate-like material 6 is obtained in which the swellable layered compound A3 is oriented in the longitudinal direction of the plate-like material.

Next, as shown in FIG. 7, fine holes 7 for degassing are made with a needle or the like in a direction perpendicular to the oriented swellable layered compound A3, that is, in the thickness direction of the plate material 6.・Form. Although the diameter of the hole 7 is not particularly limited in the present invention, it is preferably about 0.05 to 0.3 mm, more preferably about 0.05 to Q, l vs * mm. The intervals at which the holes 7 are formed are not particularly limited in the present invention, and may be formed at intervals depending on the situation in which gas blisters occur. The appropriate distance between the holes 7 under normal conditions is about 5 to 15 mm.

In addition, when forming the holes 7 as described above, if the water content of the layered compound is too high, there is a risk that the layered compound will move during drying and firing and close the holes 7. For this reason, it is preferable that the water content be as low as possible when forming the holes 7, but if the water content is too low, there is a risk that the workability etc. will deteriorate on the contrary. Therefore, when forming the holes 7, the water content of the layered compound is preferably about 60 to 130% by weight.

After drying the plate material 6 as described above by hot air drying or the like at a temperature of about 60°C, it is further dried at a temperature of 300 to 600°C.
Preferably it is fired at 450-550°C. By this firing, trace amounts of organic substances contained in the inorganic pillars 21 and reactants 21', organic pillars 5, etc. are removed from CO□, NH3,
Hz O, etc., and is removed through the holes 7... to obtain a plate-shaped inorganic layered porous material in which the inorganic compound 2 is inserted between the layers, as shown in FIG. .

The inorganic layered porous material obtained in this way has no gas blisters or interlayer spacing, and more than 40% of the total layer spacing is 30 to 600. There is little heat conduction due to convection or radiation, and the heat insulation properties in the direction of arrow B in Figure 1 are extremely excellent.

In addition, in this invention, the inorganic pillar or reactant and the organic pillar may be mixed and then inserted between the layers of the swellable layered compound, or separately inserted between the layers. good. Further, in the illustrated embodiment, a case is shown in which organic pillars are blended, but as described above, in the present invention, this organic pillar does not need to be blended.

Next, examples of the present invention will be described together with comparative examples.

(Example 1) As an inorganic pillar, a 20% by weight aqueous solution of silica sol (manufactured by Nissan Chemical Industries, Ltd. (Snowtex QXS, average particle size 50-60)), which is a colloidal inorganic compound, was used, and this was mixed with metal alcoholate B. T! (OC3H7
) The mixture was thoroughly mixed with the 2N hydrochloric acid solution of a and reacted to obtain an aqueous solution of the reactant.

The molar ratio of T i (OCff H7>4 and 2N hydrochloric acid) was 0.071:1.

The reaction solution was added to a 0.8 wt% aqueous solution of Na-montmorillonite (Nipia F manufactured by Kunimine Kogyo Co., Ltd.) that had been swollen with water in advance, and a linear combination reaction was carried out at about 60°C for 5 hours. , at this time, Na-montmorillonai 1~
．． The molar ratio of silica sol and Ti (QC3I]7) was 1:10:1.

After the reaction, a quaternary ammonium salt, octadecyltrimethylammonium chloride (Ninozan Cation AB, manufactured by NOF Corporation) was added to the reaction solution with Na-
Added at a ratio of 1 mole to 1 mole of montmorillonite, 6
After reacting for 1 hour at 0°C, this was heated to 180×18
It was placed in a mold of 0.times.100 mm, water was filtered, and a certain amount of water was removed by pressing. The pressing method was to gradually increase the pressure while checking the degree of dehydration until the maximum pressure was 100 kg/cJ.

The moisture content of the Na-montmorillonite plate-shaped body thus dehydrated was 80% by weight.

Next, holes with a diameter of 0.2 inch were formed in the thickness direction of this plate-shaped molded body at intervals of approximately IQ mm using a jig with steel needles placed at intervals of approximately 10 mm. . After forming the holes, this plate-shaped molded body was pressed again at 20 kg/cn+ to smooth out the unevenness that occurred on the surface when forming the holes. and,
This was dried with hot air at 60° C. to an absolutely dry state, and then fired in an electric furnace at 500° C. for 2 hours to obtain a plate-like inorganic layered porous material sample with a thickness of 3 mm. The obtained sample of the plate-like inorganic layered porous material was free from gas blistering and delamination. Note that when the holes were observed after firing, they could hardly be visually confirmed.

(Example 2) A plate was prepared in the same manner as in Example 1, except that polyvinyl alcohol, a water-soluble polymer compound, was used instead of octadecyltrimethylammonium chloride, and the water content at the time of hole formation was 120% by weight. A sample of an inorganic layered porous material was obtained. The obtained sample of the plate-like inorganic layered porous material was free from gas blistering and delamination.

(Example 3) A plate-like inorganic layered porous material sample was obtained in the same manner as in Example 1 except that the hole interval was set to 201. The obtained plate-like inorganic layered porous material sample had no delamination and only slight gas blistering occurred.

(Example 4) Hectorite (
A plate-like inorganic layered porous material sample was obtained in the same manner as in Example 1, except that a material (manufactured by Topy Industries, Ltd.) was used. The obtained sample of the plate-like inorganic layered porous material was free from gas blistering and delamination. Further, when the holes were observed after firing, as in Example 1, almost no holes could be visually confirmed.

(Example 5) A plate-shaped inorganic layered porous material sample was obtained in the same manner as in Example 1, except that the water content at the time of hole formation was changed to 180 ml. In the plate-like inorganic layered porous material sample obtained, many of the holes were closed due to pressing and drying after hole formation, but gas blistering caused by firing was slight.

(Comparative Example 1) An inorganic layered porous material sample was obtained in the same manner as in Example 1 except that no holes were formed. The obtained plate-like inorganic layered porous material sample had many gas blisters and was inferior in both appearance and performance.

(Comparative Example 2) An inorganic layered porous material sample was obtained in the same manner as in Example 2 except that no holes were formed. In the plate-like inorganic layered porous material sample obtained, large gas blisters occurred, and delamination also occurred in the negative part.

The porosity, interlayer distance, density, and thermal conductivity of the plate-like inorganic layered porous material samples obtained in these Examples and Comparative Examples were measured, and the results were compared to the two comparative examples of gypsum board and sand molding. It is also shown in Table 1. Note that the porosity is obtained by the following formula. The specific surface area is BE in the nitrogen adsorption method.
The average interlayer distance (pore distribution) was obtained using the CI method in the nitrogen adsorption method, respectively. The nitrogen adsorption device used was Autosorb 6 manufactured by Quantachrome. For thermal conduction measurement, a thermal conductivity measuring device using a heat flow meter method was used.

〔Effect of the invention〕

Since the method for manufacturing the inorganic layered porous material of this invention is configured as described above, there is no occurrence of gas blistering or delamination, and
It becomes possible to reliably obtain an inorganic layered porous body having homogeneous microscopic voids and excellent heat insulation properties.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view of an inorganic layered porous material, Fig. 2 is a schematic side view of a swellable layered compound, Fig. 3 is an explanatory diagram explaining the state leading to swelling, and Fig. 4 is a colloidal compound. An explanatory diagram illustrating a state in which the surface of an inorganic pillar formed by hydrolyzing an inorganic compound or metal alcoholate A is modified,
Figure 5(a) is an explanatory diagram illustrating a state in which an inorganic pillar and an organic pillar are inserted between the eyebrows of a swellable layered compound, and Figure 5fb) shows a reaction product obtained by modifying the surface of an inorganic pillar and an organic pillar. FIG. 6 is an explanatory diagram illustrating the state in which the swellable lamellar compound is inserted between the layers of the swellable layered compound, FIG. 6 is an explanatory diagram illustrating the state in which the swellable lamellar compound is oriented after the insertion reaction, and FIG. FIG. 8 is an explanatory view for explaining a state in which holes are formed in the layered compound, and FIG. 8 is an explanatory view for explaining a state in which the oriented swelling layered compound is fired without forming holes. A...Inorganic layered porous material AI...Swellable inorganic layered compound 1...Layer 2...Inorganic compound 3...Void 5...Organic pillar 7...Hole 21.21'...
・Inorganic Pillar Agent Patent Attorney Takehiko Matsumoto Figure 1 Figure 2 Figure 5 Figure 4 Figure 7 Figure 8

Claims (10)

[Claims] (1) An inorganic layered porous material in which a swellable layered compound is swollen, at least one of an inorganic pillar and an organic pillar is inserted between the layers, and fine voids are formed between the layers by orientation and drying. 1. A method for producing an inorganic layered porous material, the method comprising the step of forming fine holes for degassing in a swellable layered compound after orientation and before drying. (2) The swelling layered compound is Na-montmorillonite,
Ca-montmorillonite, acid clay, 3-octahedral synthetic smectite, Na-hectorite, Li-hectite, Na-teniolite, Li-teniolite, and
The method for producing an inorganic layered porous material according to claim 1, which is at least one selected from the group consisting of synthetic mica. (3) The method for producing an inorganic layered porous material according to claim 1 or 2, wherein the inorganic pillar is at least one of a colloidal inorganic compound and a hydrolyzate of a metal alcoholate. (4) The colloidal inorganic compound is SiO_2, Sb_2
O_3, Fe_2O_3, Al_2O_3, TiO_2
The metal alcoholate, which is at least one selected from the group consisting of , and ZrO_2 and becomes a hydrolyzate, is
Si(OR)_4, Al(OR)_3, and Ge(
The method for producing an inorganic layered porous material according to claim 3, which is at least one selected from the group consisting of OR)_4. (5) The inorganic layered porous structure according to any one of claims 1 to 4, wherein the inorganic pillar has a surface modified with at least one of a cationic inorganic compound and a metal alcoholate. How the body is made. (6) The cationic inorganic compound is a titanium-based compound, a zirconium-based compound, a hafnium-based compound, an iron-based compound,
Copper compounds, chromium compounds, nickel compounds, zinc compounds, aluminum compounds, manganese compounds,
At least one selected from the group consisting of phosphorus-based compounds and boron-based compounds, and the metal alcoholate used for modification is Ti(OR)_4, Zr(OR)_4
, PO(OR)_3, and B(OR)_3. The method for producing an inorganic layered porous material according to claim 5. (7) The method for producing an inorganic layered porous material according to any one of claims 1 to 6, wherein the organic pillar is at least one of a water-soluble polymer compound and a quaternary ammonium salt. (8) The water-soluble polymer compound is polyvinyl alcohol,
At least one selected from the group consisting of polyethylene glycol, polyethylene oxide, methylcellulose, carboxymethylcellulose, polyacrylic acid, sodium polyacrylate, and polyvinylpyrrolidone, and the quaternary ammonium salt is an octadecyl group, a hexadecyl group, 8. The method for producing an inorganic layered porous material according to claim 7, which has at least one group selected from the group consisting of a tetradecyl group and a dodecyl group. (9) After drying, the first claim further includes firing.
A method for producing an inorganic layered porous material according to any one of Items 1 to 8. (10) The method for producing an inorganic layered porous material according to any one of claims 1 to 9, wherein the voids are 30 to 600 Å.