WO2006135010A1

WO2006135010A1 - Functional porous filler and process for production thereof

Info

Publication number: WO2006135010A1
Application number: PCT/JP2006/312043
Authority: WO
Inventors: Katsuhiro Kikuchi; Hiroshi Idei
Original assignee: Akebono Brake Industry Co., Ltd.
Priority date: 2005-06-16
Filing date: 2006-06-15
Publication date: 2006-12-21
Also published as: JP2006348188A

Abstract

Disclosed are a functional porous filler having hydrophobic layered substances each of which has a uniform pore size and which are three-dimensionally bound to each other, and a process for producing the functional porous filler readily and with good reproducibility. A functional porous filler comprising composite materials each having an inorganic substance intercalated between layered substances, the composite materials being three-dimensionally bound to each other to form the filler; and a process for producing the functional porous filler comprising the steps of reacting a layered clay mineral dispersed in a solvent or a powder of the layered clay mineral with a colloidal solution of a precursor of an inorganic substance at room temperature or under heating to prepare an interlayer-crosslinked product of the layered clay mineral and the inorganic substance and form a three-dimensional structure of the thin-layered, platy particles.

Description

Specification

Porous functional filler and method for producing the same

Technical field

[0001] The present invention relates to a structure in which layered substances having hydrophobic and uniform pore diameters are sterically bonded, and can be advantageously used for functional products such as friction materials that require high strength and hydrophobicity, and The present invention relates to a method for manufacturing the structure easily and with high reproducibility.

Background art

[0002] For the purpose of preventing noise generated during braking, various techniques have been developed that utilize a layered material having high water absorption, such as zeolite, as a friction and wear adjusting component to be blended with the raw material of the friction material. For example, Patent Document 1 describes an inorganic material having a planar crystal structure such as fibrous material, My force, and talc as a friction material that can effectively prevent noise during braking while preventing a decrease in braking force as much as possible. Discloses a friction material made of a thermosetting resin containing a granular material and a manufacturing method thereof.

[0003] In addition, Patent Document 2 discloses a friction component that has good squeal performance during braking, good fade resistance and wear resistance, as a fiber component, a thermosetting resin component, and a filler powder component. Disclosed is a friction material comprising resin coated vermiculite. Further, Patent Document 3 discloses a non-asbestos for automobiles that includes high-water-absorbing zeolite as a fiber base material, a binder, and a friction modifier as an automobile brake pad that prevents the generation of noise called creep creep. A brake pad is disclosed.

[0004] Patent Document 1: Japanese Patent No. 2867661

Patent Document 2: Japanese Patent No. 2827140

Patent Document 3: Japanese Patent Laid-Open No. 2000-38571

Disclosure of the invention

Problems to be solved by the invention

[0005] Conventionally, since a layered material generally has high water absorption between layers, when used as a product filler, deformation and cracking occur due to expansion during water absorption. In addition, when a composite material using a layered substance as a filler is compression-molded, plate-like particles with a high aspect ratio are molded. Since it is oriented perpendicular to the pressure direction, the strength in the direction perpendicular to the molding pressure direction decreases. Therefore, from the two points of water absorption and strength reduction, there is a problem that general layered materials are used as a filler for functional products.

In addition, the use of porous materials such as zeolite has a problem that the quality of water-absorbing high-friction materials and other fillers deteriorates, and sufficient humidity control is required for storage security.

[0006] The present invention has been made in view of such a conventional problem, and a structure in which a layered substance having a hydrophobic and uniform pore size is three-dimensionally bonded, and the structure can be obtained simply and easily. The object is to provide a method for manufacturing with good reproducibility.

The invention's effect

[0007] The present invention provides a layered clay mineral by reacting a layered clay mineral or a layered clay mineral powder dispersed in a solvent such as water with a sol (colloid) solution of an inorganic precursor at room temperature or while heating. A three-dimensional framework of thin plate-like particles is formed at the same time that an interlayer crosslinked body of mineral and inorganic material is produced. When the heat treatment is further performed, the wet gelled material on the interlayer and the layer surface undergoes a dehydration condensation reaction depending on the heating conditions to become a mixture of inorganic hydroxide and inorganic oxide or inorganic oxide, and adheres to the surface and interlayer of the clay mineral. Since it becomes the strut between the expanded layers, swelling due to water absorption is suppressed. On the other hand, it acts as an inorganic binder that firmly supports the three-dimensional skeleton. Finally, a structure in which layered substances having hydrophobic and uniform pore sizes are sterically bonded is obtained.

The matters described above are shown in Fig. 1 as an image of the structure. In Fig. 1, 1 is a layered clay mineral and 2 is an inorganic substance.

Means for solving the problem

[0008] The porous functional filler according to the present invention has a structure in which a layered substance having a hydrophobic and uniform pore diameter is sterically bonded to absorb water between layers and a direction of molding pressure during compression molding. Therefore, the problems of water absorption and strength reduction are solved.

That is, the present invention has the following configuration in order to achieve the above object. (1) A porous functional filler, which is a composite material in which an inorganic substance is inserted between layers of a layered substance and has a structure in which the composite material is sterically bonded.

(2) A layered clay mineral and an inorganic cross-linked material are produced by reacting a layered clay mineral dispersed in a solvent, or a colloidal solution of a layered clay mineral and an inorganic precursor at room temperature or while heating. A method for producing a porous functional filler, characterized in that a composite material is produced by three-dimensionalizing thin-layered plate-like particles.

[0010] (3) The layered clay mineral is at least one of natural clay minerals or artificial synthetic clays having a cation exchange capacity such as kaolinite, smectite, vermiculite, mica, brittle mica, chlorite and the like. A method for producing a porous functional filler according to (2), characterized in that:

(4) Inorganic strength Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V, Y, As, Sc, Cr, Nb, Mo, Ca, Mg, Pb, Sr, Zn, Cu, Ni, Co, Mn, Be, Ba force As described in (2) above, characterized in that it is an oxide of one or more metals and metalloids or a mixture of oxide and hydroxide. A method for producing a porous functional filler.

(5) The colloidal solution of the inorganic precursor is Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V, Y, As, Sc, Cr, Nb, Mo, Ca, Mg, Pb, Sr, Zn, Cu, Ni, Co, Mn, Be, Ba force One or more kinds of organic compounds such as metal and metalloid alkoxides, organic salts, halides, inorganic or organic one kind A porous material as described in (2) above, which is dissolved or dispersed in a solvent or a mixed solvent of two or more of the solvents, or hydrolyzed through aging after dissolution or dispersion A method for producing functional fillers.

(6) Colloidal solution strength of the above-mentioned inorganic precursor In the solution, polybutyl alcohol, polyvinyl butyral, acetate acetate, butyl chloride, methacryl, acrylic, styrene, polyethylene, polypropylene, polyamide, cellulose, The method for producing a porous functional filler according to (2) above, wherein the thermoplastic resin of isobutylene or vinyl ether is dissolved or dispersed.

Brief Description of Drawings

FIG. 1 is an image view showing a structure of a porous functional filler of the present invention.

Explanation of symbols [0012] 1 layered clay mineral

2 Inorganic

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, as the layered clay mineral, for example, natural clay minerals having artificial cation exchange ability such as kaolinite, smectite, vermiculite, mica, brittle mica, chlorite and artificial synthetic clay are used.

In the present invention, the inorganic substance includes Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V, Y, As, Sc, Cr, Nb, Mo, Ca, Mg, Pb, Sr. One or more metal and metalloid oxides selected from the group consisting of Zn, Cu, Ni, Co, Mn, Be, and Ba, or a mixture of oxide and hydroxide are used.

[0014] The sol (colloid) solution of the inorganic precursor is Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V, Y, As, Sc, Cr, Nb, Mo, Ca, Mg, Pb, Sr, Zn, Cu, Ni, Co, Mn, Be, Ba force One or more kinds of organic compounds such as metal and metalloid alkoxides, organic salts, halides, inorganic or organic 1 A solvent that is dissolved or dispersed in a mixed solvent of two or more kinds of solvents, or that is hydrolyzed through aging after dissolution or dispersion is used.

Furthermore, if necessary, the solution may contain polybutyl alcohol, polybutyl butyral, butyl acetate, chlor chloride, methacryl, acrylic, styrene, polyethylene, polypropylene, polyamide, cellulose, isobutylene, A solution obtained by dissolving or dispersing a butyl ether thermoplastic resin is used.

These inorganic precursor colloidal solutions (sols) are formed in the form of ceramic precursors and metal oxides in the composite material having the structure shown in FIG.

[0015] The solvent for dispersing the layered clay mineral is one kind of inorganic or organic solvent, or a mixed solvent of two or more kinds of solvents, and a mixture of acid, neutral and alkaline solvents is used. . Preferable solvents include ethanol from the viewpoints of safety in work environment and low cost.

Example

[0016] Hereinafter, the present invention will be described in detail and specifically by way of examples. The embodiment is not limited in any way.

[0017] Example 1 and comparative examples:! To 2

10 g of synthetic fluorine mica was added to 600 ml of distilled water and stirred well. Dilute 23 g of tetraethoxysilane with 200 ml of ethanol, add 20 g of acetic acid and 8 g of distilled water, concentrate at a temperature of 80 ° C or lower until the volume reaches 125 ml, and then add it to the synthetic fluoric mica dispersion. After stirring for 5 hours at C, ripening treatment was performed for 2 hours in a heating furnace at 200 ° C. The filler of the present invention was obtained through washing with water, filtration, drying and pulverization. In the above operation, when acetic acid and distilled water are added to an ethanol solution of tetraethoxysilane, tetraethoxysilane is hydrolyzed to form silica zonole, which is concentrated to obtain a concentrated silica sol solution.

[0018] A test piece containing 25% by volume of phenol resin, 55% by volume of calcium carbonate, and 20% by volume of the filler of the present invention was prepared by compression molding, and a water absorption test, a strength test, and a porosity measurement were performed. . As a comparative example 1, a synthetic fluorine mica was prepared, and as a comparative example 2, a test piece to which calcium carbonate was added was prepared and subjected to the same test.

[0019] (Water absorption test)

When the water absorption was confirmed by leaving it in an atmosphere with a temperature of 50 ° C and humidity of 95% for 72 hours, the test piece using synthetic fluorine mica (Comparative Example 1) was expanded and cracked. The test piece to which the above filler was added did not show cracking with small expansion similar to that to which calcium carbonate (Comparative Example 2) was added.

[0020] (Strength test)

In the strength test when sheared in the direction perpendicular to the molding pressure, the test piece to which the filler of the present invention was added was about twice as strong as the test piece to which the synthetic fluorinated mica (Comparative Example 1) was added. The test piece to which Comparative Example 2) was added showed about 1.5 times the strength. The strength of the test piece to which the filler of the present invention was added when the bending test was performed in the same direction as the molding pressure was about twice that of the test piece to which calcium carbonate (Comparative Example 2) was added. The test piece to which Comparative Example 1) was added showed the same strength. Table 1 shows the results of these experiments.

[0021] (Measurement of porosity) The test piece to which the filler of the present invention is added is about twice as large as the test piece to which the pore strength of synthetic fluorine mica (Comparative Example 1) is added, and the test piece to which calcium carbonate (Comparative Example 2) is added. On the other hand, the porosity of several lOnm level was close to 0.

[Table 1] Table 1 Strength test results

[0023] The present invention has been described in detail and with reference to specific embodiments. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. .

This application is based on a Japanese patent application filed on June 16, 2005 (Japanese Patent Application No. 2005-176655), the contents of which are incorporated herein by reference.

Industrial applicability

[0024] Since the porous functional filler of the present invention is a composite material having a structure in which an inorganic substance is inserted between layers of a layered substance and is sterically bonded, a three-dimensional structure having a hydrophobic and uniform pore size is provided. The characteristics of the layered material with a structurally bonded structure are exhibited, and the disadvantages of the conventional layered material, such as water absorption between layers and orientation perpendicular to the molding direction during compression molding, are suppressed and eliminated. It is a useful filler (filler) that has wide applicability as a friction material for brakes, structural adhesives, structural members, and molding materials for automobiles, railway vehicles, and industrial machinery.

Claims

The scope of the claims

[1] A porous functional filler, which is a composite material in which an inorganic substance is inserted between layers of a layered substance and has a structure in which the composite material is sterically bonded.

[2] Layered clay mineral and inorganic layered cross-linked material are prepared by reacting layered clay mineral dispersed in solvent or colloidal solution of layered clay mineral and colloidal solution of inorganic precursor at room temperature or while heating. A method for producing a porous functional filler, characterized in that a composite material is produced by three-dimensionalizing thin plate-like particles.

[3] The layered clay mineral is one or more of natural clay minerals or artificial synthetic clays having a cation exchange ability such as kaolinite, smectite, vermiculite, mica, brittle mica, chlorite and the like. The method for producing a porous functional filler according to claim 2.

[4] The inorganic substance is Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V, Y, As, Sc, Cr, Nb

, Mo, Ca, Mg, Pb, Sr, Zn, Cu, Ni, Co, Mn, Be, Ba, one or more metal and metalloid oxides or a mixture of oxide and hydroxide 3. The method for producing a porous functional filler according to claim 2, wherein the porous functional filler is provided.

[5] Colloidal solution force of the inorganic precursor Si, Ti, Zr, Sn, Ge, Al, B, Fe, Ga, P, V

, Y, As, Sc, Cr, Nb, Mo, Ca, Mg, Pb, Sr, Zn, Cu, Ni, Co, Mn, Be, Ba force, etc. Organic compounds, organic salts, and halides are dissolved or dispersed in one kind of inorganic or organic solvent, or a mixed solvent of two or more kinds of such solvents, or hydrolyzed through aging after dissolution or dispersion. 3. The method for producing a porous functional filler according to claim 2, wherein the porous functional filler is used.

[6] Colloidal solution strength of the above-mentioned inorganic precursor In the solution, polybulualcohol, polybutybutyral, acetic acid butyl, chlorinated butyl, methacrylic, acrylic, styrene, polyethylene, polypropylene, polyamide, cellulose 3. The method for producing a porous functional filler according to claim 2, wherein a thermoplastic resin of isobutylene type or butyl ether type is dissolved or dispersed.