JPH0959076A - Lightweight fiber reinforced ceramics - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide a fiber-reinforced ceramics having excellent fire resistance and achieving weight reduction. (A) Fine powder of metal oxide having a specific particle size,
(B) Specific soluble siloxane polymer, (C) Specific 3
An inorganic fiber product is impregnated with a liquid or sheet of a matrix composition containing a functional silane compound, (D) an organic peroxide, (E) a specific radically polymerizable monomer, and (F) zeolite. It is characterized in that the prepreg formed by heating and permeating is heated and pressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight fiber reinforced ceramics, and more particularly to a lightweight fiber reinforced ceramics which has excellent heat shielding properties and can be reduced in weight to a specific gravity equivalent to that of conventional fiber reinforced plastics.

[0002]

2. Description of the Related Art Conventionally, as an aircraft interior material, for example, a sheet made by impregnating glass fiber with phenol resin as an organic flame-retardant material on the surface of an aramid honeycomb (Nomex, etc.) and curing it is used. An interior material is known which is provided with a film made of polyvinyl fluoride (Tedlar or the like) applied and a film made of transparent polyvinyl fluoride not printed in this order.

[0003] Sheets or films made of such materials are used as surface covering materials because of their excellent flexibility and easy handling.

[0004] However, such interior materials using organic flame retardants have a problem that a large amount of smoke and toxic gas is generated when a fire occurs.

[0005] For example, in the Chinese aircraft accident that occurred at Nagoya Airport in April 1994, it is considered that the fire that occurred in addition to the impact of the crash caused a great deal of casualties. Conventional interior materials composed of organic flame retardants and wallpaper generate a large amount of smoke and toxic gas, which makes it impossible to evacuate quickly.

In recent years, higher fire resistance has been required for aircraft interior materials.

[0007] For example, the latest standards of the Federal Aviation Administration (FAA) for cabin interior materials include standards for smoke density (Ds) in addition to conventional standards such as maximum heat release. Therefore, when retrofitting old interior materials (for example, side panels), it is necessary to satisfy the latest standards. For this purpose, it is conceivable to change all of them to new ones, but there is a great problem in terms of cost. In addition, it is very difficult to satisfy such requirements by a method of further coating a conventional organic material on a surface coating material of an old interior material. Further, it is expected that interior materials will be required to have increasingly higher fire resistance performance in the future due to demands for improved safety.

[0008] Such a demand for improvement in fire resistance performance is not limited to aircraft, and similarly exists for interior materials of other vehicles and buildings.

Application of fiber-reinforced ceramics to these fields has also been considered.

Normal fiber reinforced ceramics are titanium,
Although it is lighter than metals with high heat resistance such as Inconel and Hastelloy, it has the drawback of being heavier than organic flame retardants.

Not only aircraft but also interior materials and heat-resistant members (for aircraft engines, machines such as nozzles and plugs,
It is required that the weight of the equipment (apparatus or device) is much lighter while maintaining heat resistance (fire resistance).

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lightweight fiber reinforced ceramic having excellent fire resistance, especially heat shielding properties.

[0013]

The invention according to claim 1 for solving the above-mentioned problems is the following (A) component, (B)
A sheet of a prepreg obtained by impregnating or heat-permeating a liquid or sheet-like material of a matrix composition containing the component, the component (C), the component (D), the component (E), and the component (F) into a product of inorganic fibers. Laminated or molded into a shape, temperature 120 ℃
It is a lightweight fiber reinforced ceramics characterized by being heated and pressed under conditions of ˜250 ° C. and pressure of 2˜10 kg / cm, and (A) component; a metal oxide having an average particle size of 1 μm at the maximum. Fine powder, (B) component; soluble siloxane polymer having double chain structure, (C) component, at least one ethylenically unsaturated double bond
A trifunctional silane compound contained in an individual molecule, (D) component; organic peroxide, (E) component; at least two ethylenically unsaturated double bonds.
Radical-polymerizable monomer in individual molecule, (F) component; zeolite The invention according to claim 2 is such that the compounding amount of the (A) component in the matrix composition is 50 to 250 parts by weight, ( B)
80 to 170 parts by weight of the components, 25 to 125 parts by weight of the component (C), and 1 to 4 of the component (D).
4. The lightweight fiber-reinforced ceramics according to claim 1, wherein the amount of the component (E) is 25 to 125 parts by weight, and the amount of the component (F) is 250 to 450 parts by weight. In the invention, the inorganic fiber is glass fiber,
The lightweight fiber according to any one of claims 1 and 2, which is at least one selected from the group consisting of alumina fibers, silica fibers, tyranno fibers, and various fibers containing alumina and / or silica as a main component. It is reinforced ceramics, The invention of Claim 4 is a lightweight fiber reinforced ceramics in any one of the said Claims 1-3 whose product of the said inorganic fiber is either a tow alignment product or knitted fabric. .

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

The matrix composition used in the production of the lightweight fiber-reinforced ceramics according to the present invention comprises the following components (A), (B), (C) and (D):
It contains the component (E) and the component (F).

Component (A); fine powder of metal oxide having a maximum average particle size of 1 μm; component (B); soluble siloxane polymer having a double chain structure; component (C); ethylenically unsaturated double bond. At least 1
A trifunctional silane compound contained in an individual molecule, (D) component; organic peroxide, (E) component; at least two ethylenically unsaturated double bonds.
Radical-polymerizable monomer in individual molecule, component (F); zeolite.

As the metal oxide which is the component (A),
Single oxides such as silica, alumina, titanium oxide, lithium oxide, zinc oxide, tin oxide, calcium oxide, magnesium oxide, boron trioxide, zirconia, partially stabilized zirconia, vanadium pentoxide, barium oxide, yttria and ferrite And complex oxides such as mullite, steatite, forsterite, cordierite, aluminum titanate, barium titanate, strontium titanate, potassium titanate and lead zirconate titanate. One of these can be used alone, or two or more of them can be used in combination.

Among these metal oxides, the preferable one is
Alumina, silica, titanium oxide and the like are preferred, and alumina is more preferred.

The average particle size of the metal oxide used in the present invention is 1 μm at the maximum, preferably 0.5 μm at the maximum. The fine powder of the metal oxide having such a fine particle size is densely packed by the component (B) in the three-dimensional network mainly formed by the components (C), (D) and (E). It is included in a joined state. Therefore, when a metal oxide having the above-mentioned average particle size is used, a lightweight fiber reinforced ceramic excellent in properties such as fracture toughness can be obtained. On the other hand, if a metal oxide having an average particle size of more than 1 μm is used, a lightweight fiber reinforced ceramic having good strength cannot be obtained.

The metal oxide fine powder that has been exposed to the atmosphere has a hydroxyl group on at least a part of its surface, and therefore effectively functions in the bonding effect described later. In contrast,
Fine powders of metal nitrides, metal carbides and the like cannot be used for producing the lightweight fiber-reinforced ceramics of the present invention because they do not have sufficient hydroxyl groups on a part of their surfaces.

The soluble siloxane polymer having a double chain structure which is the component (B) may be a homopolymer or a copolymer. This component (B) functions as a binder for the metal oxide.

In general, a so-called ladder-type organic polymer having a double-chain structure is superior in heat resistance to a linear organic polymer, is rigid and has a small heat shrinkage. However, organic polymers, even ladder-type,
It is not preferable for the production of the lightweight fiber-reinforced ceramics of the present invention because it is thermally decomposed or contracted when heated to a temperature of ℃ or more and a large amount of gas is generated.

As a result of various studies on the binder of fine powder of metal oxide, the present inventors have found that the siloxane homopolymer or siloxane copolymer having a double chain structure has a high second-order transition point (glass transition point). It has been found that it has a good bonding effect with respect to oxides, and most of it is converted to a ceramic composition after pyrolysis, so that it is optimal as a binder for metal oxide fine particles used in the present invention. The soluble siloxane polymer having a double-chain structure in the present invention includes what is called an oligomer.

A raw material for preparing a siloxane polymer having a double-chain structure is represented by the chemical formula R'Si (OR) ₃
(Wherein R is an alkyl group such as a methyl group or an ethyl group,
R ′ represents an aliphatic, alicyclic, or aromatic substituent such as an alkyl group, a phenyl group, a vinyl group, a cyclopentyl group, a cyclohexyl group, and a methacryloyl group. )).

As this trialkoxysilane, methyltriethoxysilane, methyltrimethoxysilane, propyltrimethoxysilane, methyltriisopropoxysilane, methyltributoxysilane, octyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane and the like can be mentioned.

The soluble siloxane polymer having a double chain structure which is the component (B) is, for example, JFB Brown et at., J.
Polymer Sci., Part C No. 1 p. 83 (1963), prepared by hydrolyzing one or more trialkoxysilanes using an acid catalyst and condensing them by a known method described in (1963). be able to. These are also called polysilsesquioxanes and are generally represented by the following chemical formula.

[0027]

Embedded image

However, R ₁ represents a hydrogen atom or R in the chemical formula R′Si (OR) ₃ , and R ₂ and R ₃ represent R ′ in the chemical formula R′Si (OR) ₃ .

Examples of the polysilsesquioxane include polymethylsilsesquioxane, polyphenylsilsesquioxane, polyvinylmethylsilsesquioxane, polyphenylmethylsilsesquioxane, polyphenylpropylsilsesquioxane and polymethyl. Examples thereof include -n-hexylsilsesquioxane and polyphenylmethacryloxypropylsilsesquioxane.

Of these, polyphenylsilsesquioxane, polyphenylmethylsilsesquioxane and polyphenylethylsilsesquioxane are preferable. In the case of a copolymer, the molar ratio of phenyl group to methyl group or ethyl group (phenyl group / methyl group or ethyl group) is preferably 2/1 to 1/2. These are because the heat shrinkage rate during heating is small and the production is easy.

The molecular weight of the siloxane polymer which is preferable as the binder is not particularly limited, but is usually 1,000 to 10,000, particularly 1,500 to 5,000.
It is preferably 0.

For example, polyphenylsilsesquioxane is soluble in a solvent, can form a tough film from the solution, and has a glass transition point Tg of 300.
To 400 ° C., so that thermal deformation during curing can be minimized.

The siloxane polymer does not undergo main chain scission even when heated to 900 ° C., and is converted into a ceramic structure such as amorphous silicone oxycarbide (Si--C--O) in high yield. To do. On the other hand, when an organic polymer is used as a binder, the organic polymer is thermally decomposed in the process of baking at normal pressure, the bonding strength between metal oxides is lost, and cracks are generated.

As is clear from the above description, the soluble siloxane polymer having a double chain structure in the present invention is
When used as a binder, shrinkage is small even when heated to a high temperature, and the heat-resistant protective sheet shrinks less because it is itself ceramicized. Therefore, the soluble siloxane polymer having a double-chain structure is particularly advantageous for a calcination operation under normal pressure and under unrestricted conditions. Here, the normal pressure includes a case where the operation of increasing or decreasing the pressure is not intentionally performed.

In the present invention, among the soluble siloxane polymers having a double-chain structure, those having a silanol group or an alkoxy group at the molecular end are particularly advantageous. The soluble siloxane polymer having a silanol group or an alkoxy group at a molecular terminal has an affinity for the component (A) having a hydroxyl group on at least a part of its surface, that is, fine particles of metal oxide and the soluble siloxane polymer, Easily inter-dispersed. Further, they react and bond with each other during the heating and pressurizing treatment, and are integrally ceramicized during the firing.

In the present invention, the mutual affinity with the component (A) and the component (B) and the component (E) which is an organic substance is increased to facilitate the formation of a strong network structure in the matrix and to form the matrix substance. None of the known silane coupling agents can be used in order to achieve the action and effect of enhancing the bondability with the inorganic fiber.

In the present invention, a trifunctional silane compound having at least one ethylenically unsaturated double bond in the molecule is used as the component (C). The component (C) easily bonds to the molecular terminals of the soluble siloxane polymer having a double-chain structure, which is the component (B), and the metal oxide fine particles. These bonds are formed by dehydration condensation of hydroxyl groups upon heating. In addition, the trifunctional silane compound as the component (C) easily reacts with the surface hydroxyl group of the inorganic fiber, so that the bonding property between the matrix composition and the inorganic fiber can be improved. Therefore, in this regard, oxide-based inorganic fibers are preferable to nitride-based inorganic fibers and carbide-based inorganic fibers. Further, the ethylenically unsaturated double bond contained in the component (C) reacts with the radical catalyst as the component (D) and is incorporated into a network structure.

Examples of the trifunctional silane compound having at least one ethylenically unsaturated double bond in the molecule include vinyltris (β-methoxyethoxy) silane, vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyl. Examples thereof include trimethoxysilane and γ-methacryloxypropyltriethoxysilane. Among them, γ-methacryloxyalkyl trialkoxysilane is preferable, and γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropyltriethoxysilane are particularly preferable.

A cross-linking agent is required to form a network structure in the cured product. In the present invention, the organic peroxide as the component (D) is effective as a crosslinking agent.

In the present invention, in order for the organic peroxide to act effectively, it is not preferable that the organic peroxide decomposes to generate radicals during the work before curing, and therefore the temperature for obtaining the half-life of 10 hours is required. Is preferably 100 ° C. or higher.

Examples of such organic peroxides include dicumyl peroxide, t-butylcumyl peroxide,
Di-t-butyl peroxide, α, α-bis (t-butylperoxyisopropyl) benzene, di-t-butylperoxydiisopropylbenzene, 2,5-dimethyl-2,5-di (t-butylperoxy ) Hexin-
3,1,1-bis (t-butylperoxy) -3,3,3
Examples thereof include 5-trimethylcyclohexane, 2,2-bis (t-butylperoxy) butane, and 2,2-bis (t-butylperoxy) octane.

The matrix composition in this invention is
In addition to the organic peroxide which is a cross-linking agent as the component (D), a radical polymerizable monomer having at least two, preferably three ethylenically unsaturated double bonds as the component (E) is contained. . This component (E), as a co-crosslinking agent, contributes to the formation of a stronger three-dimensional network structure by curing. The matrix composition containing the component (E) contains fine particles of metal oxide and changes to a network structure having an effective and sufficient chain length that does not deform when heated.

As the component (E), ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, ethylene glycol diitaconate, tetramethylene glycol diitaconate, ethylene glycol dicrotonate, ethylene glycol di Examples thereof include maleate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and the like. In the above example,
The expression (meth) acrylate refers to both acrylate and methacrylate.

Among these, radical polymerization is excellent,
Di (meth) acrylates of polyhydric alcohols and / or tri (meth) acrylates of polyhydric alcohols, such as trimethylolpropanetriene, provide an effective chain length and excellent tackiness to a prepreg as described below. (Meth) acrylates are preferred.

Examples of the zeolite as the component (F) include natural zeolite and synthetic zeolite,
Synthetic zeolites are preferred over natural zeolites.

In the present invention, whether a natural zeolite or a synthetic zeolite is used, a zeolite having a bulk specific gravity of 0.3 to 0.7 is preferable. When the bulk specific gravity is within the above range, the weight reduction and heat shielding property of the fiber-reinforced ceramics obtained by using the matrix composition containing the components (A) to (F) can be well achieved, while If the specific gravity is less than 0.3, it may be difficult to impregnate the inorganic fiber product with the ceramic composition.

In the present invention, at least 2 of its own weight
Zeolites that adsorb 0%, preferably 20-30% water are preferred. Zeolite that adsorbs 20% or more of water absorbs heat of evaporation of water when desorbing water from zeolite and heat of 210 cal or more as an endothermic amount when desorbing zeolite. Therefore, at the time of fire, the lightweight fiber-reinforced ceramics containing such a zeolite can exhibit an excellent heat shielding effect of absorbing a large amount of heat and delaying heat conduction.

Among these, zeolites such as synthetic zeolite (for example, aluminosilicate) are preferable because they have good endothermic reactivity and low specific gravity.

The synthetic zeolite is represented by the following composition formula, for example.

M _{X / n.} [(AlO ₂ ) _X. (SiO ₂ ).
_Y ] · ZH ₂ O However, M is a metal cation having a valence of n, the sum of X and Y is the number of tetrahedra per unit lattice, and Z is the number of moles of water molecules.

Examples of the metal cation in the synthetic zeolite include alkali metals such as K and Na, alkaline earth metals such as Mg and Ca, and the like.

The preferred synthetic zeolite has a pore size of 3 to 9Å, preferably 4 to 7Å and an average particle size of 1
Is about 4 μm, and the internal metal is at least one selected from the group consisting of K, Na, Mg, and Ca, preferably Ca.

As the synthetic zeolite, Zeostar KA-1 manufactured by Nippon Kagaku Kogyo Co., Ltd., in which K is a cation, is used.
00P, Zeostar KA-110P, Zeostar KA-
110L, Zeostar KA-112L, Zeostar NA-100P with Na as a cation, Zeostar NA-1
10P, Zeostar NA-110L, Zeostar NA-
112L, Zeostar NX-100P, Zeostar NX
-110P, Zeostar NM-100P, Zeostar N
M-110L, Zeostar NM-112L, Zeostar NM-110S, Zeostar NM-112S, Zeostar GA-100P with Mg as cation, Zeostar CX-100P with Ca as cation, Zeostar CX-
Commercial products such as 110P are listed.

Each component constituting the matrix composition described above is dissolved or dispersed in an organic solvent.

The type of solvent may be appropriately selected depending on the type of each constituent and the mixing ratio thereof. Solvents suitably used in the present invention are selected from alcohols, aromatic hydrocarbons, alkanes, ketones, nitriles, esters, glycol esters and the like. Preferably, the solvent is completely removed prior to curing, and thus a solvent such as, but not limited to, acetone with a low boiling point is preferred. These solvents may be used alone or in combination of two or more.

In the present invention, the above-mentioned component (A)
The component (F) is preferably dissolved or dispersed in the solvent as evenly as possible so as to give the lightweight fiber-reinforced ceramics a dense structure. for that purpose,
Dissolving each of the component (B), the component (C), the component (D), the component (E) and the component (F) with stirring,
The component (A) may be added to the obtained solution and stirring may be continued until each component is uniformly dispersed. Alternatively, all of the components (A) to (F) may be mixed in a solvent at the same time. The effect of the present invention can also be achieved by employing a method of adding to the above and stirring sufficiently. Further, a trace amount of a dispersion stabilizer such as a known surfactant may be added. Furthermore, as long as the properties of the matrix composition are not impaired, addition of known additives is not prevented.

The ratio of each component in the matrix composition is
It is appropriately selected depending on the type of each component and the performance of the lightweight fiber reinforced ceramics combined with it. In many cases, the matrix composition has the following component proportions.

That is, the compounding amount of the component (A) is 50 to 2
50 parts by weight, preferably 50 to 150 parts by weight, the blending amount of component (B) is 80 to 170 parts by weight, preferably 100 to
150 parts by weight, the amount of the component (C) is 25 to 125 parts by weight, preferably 30 to 80 parts by weight, the amount of the component (D) is 1 to 4 parts by weight, preferably 1.5 to 3 parts by weight, (E)
The blending amount of the components is 25 to 125 parts by weight, preferably 25 to 125 parts by weight.
The amount of 100 parts by weight and the component (F) is 250 to 45.
It is 0 part by weight, preferably 350 to 450 parts by weight.

The tackiness of the prepreg is adjusted by the amount of the component (E) in combination with other components. Therefore, the role of the component (E) plays an important role not only in forming a network structure but also in forming tackiness, which is an important effect of the present invention.

As will be described later, the matrix composition used in the present invention can be used while having a solvent, or can be used as a sheet by removing the solvent.

The prepreg used in the present invention is produced by impregnating or heating and impregnating a liquid or sheet of the above matrix composition into a tow of inorganic fiber or its product.

The inorganic fiber may be heated to at least 500 ° C. or lower, preferably 1,000 ° C. or lower, and more preferably 1,200 ° C. or lower in either an inert atmosphere or an oxidizing atmosphere such as air. It is preferable to keep the strength for practical use. Examples of materials satisfying such conditions include nitride-based inorganic fibers, carbide-based inorganic fibers, oxide-based inorganic fibers, and carbon fibers. These inorganic fibers have sufficient heat resistance and reinforcing effect required in the present invention.

Preferred inorganic fibers are glass fibers,
Alumina fiber, silica fiber, Tyranno fiber (Si-Ti-
CO), and oxide-based inorganic fibers composed of various fibers containing alumina and / or silica as a main component.

In the present invention, glass fibers such as E glass fiber and S glass fiber are particularly preferable, and E glass fiber is particularly preferable. In general, glass fibers have higher room temperature strength than other oxide-based inorganic fibers, so that thin lightweight fiber-reinforced ceramics can be obtained while maintaining a constant fracture toughness, and therefore suitable for curved surfaces of interior materials, for example. Can be used for

When a commercially available product is used as the inorganic fiber,
It is preferable that the sizing agent attached is removed before use. The inorganic fiber is used as a towed product, or as a knitted or woven fabric.

The prepreg according to the present invention includes a solvent method (also referred to as a wet method) and a hot melt method (also referred to as a dry method), which are used in the production of conventional epoxy resin prepregs. It can be manufactured using similar techniques.

In the method according to the solvent method, the inorganic fiber tow or its product is dipped in the liquid of the matrix composition,
After squeezing out excess liquid, by blowing hot air or passing through a dryer to remove the solvent,
A prepreg is obtained.

In the hot melt method, a sheet-like material having a predetermined basis weight (this term includes a film-like material as a concept) is formed from a liquid of a matrix composition, and a tow of inorganic fibers or an inorganic fiber is formed. By laminating the sheet-like material on one side or both sides of the product, or by alternately laminating the sheet-like material with a tow of inorganic fibers or a product of inorganic fibers, and heating the same to a temperature of 120 ° C. or less. A prepreg can be obtained by impregnating the matrix composition between the inorganic fibers while reducing the viscosity of the sheet material. The prepreg thus obtained has sufficient tackiness and drapeability for forming a laminate, and sufficient outtime performance in operation.

The prepreg thus manufactured is
The sheet is formed into a sheet by a known laminating method or a filament winding method, and then subjected to a heating and pressing treatment, that is, a curing treatment. It should be noted that in the present invention, the curing reaction is sufficiently completed by the one-stage curing, so that the two-stage curing (including the preliminary curing) and the three-stage curing (including the preliminary curing and the post-curing) are not required. That is. However, in some cases, these pre-curing and post-curing may be performed.

The heating / pressurizing condition is that the heating temperature is 1
20-250 ° C., preferably 130-180 ° C., pressure 2-10 kg / cm ² , preferably 3-5 kg / cm <sup>2
2. The</sup> processing time is 10 to 60 minutes, preferably 15 to 30 minutes.

This heating / pressurizing treatment is performed in an autoclave after a vacuum bag or by using a hot press. The latter is advantageous because sheets having a uniform thickness can be produced.

The lightweight fiber-reinforced ceramics thus obtained can be used to process various so-called thick products having a large wall thickness, and by utilizing this, so-called thin products having a small wall thickness can be used. It can also be processed into various products.
When manufacturing a thick product, the lightweight fiber-reinforced ceramics usually has a thickness of 0.1 to 5 mm, preferably 0.1 to 3 mm. When the thickness is within the above range, sufficient fire resistance can be given to the interior material, a certain degree of flexibility is ensured, and the specific gravity equivalent to that of the conventional fiber-reinforced plastic is maintained, so that the conventional fiber Lighter than reinforced ceramics.

As a result, the lightweight fiber-reinforced ceramics can be applied not only to interior materials for vehicles and buildings but also to general heat-resistant members such as nozzles and plugs in aircraft engines and piping for high temperature gas reactors.

[0074]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described more specifically below with reference to embodiments of the present invention. It goes without saying that the present invention is not limited to the following embodiments.

(Example 1) <Preparation of matrix composition> Alumina powder (average particle size; 0.4 μm) was placed in a ball mill containing ceramic balls.
m) 100 parts by weight, synthetic zeolite (Nippon Kagaku Kogyo KK; Zeostar CA-100P, water absorption 20%, bulk specific gravity 0.4) 400 parts by weight, polyphenylmethylsilsesquioxane (molecular weight 2,300, phenyl) / Methyl ratio = 6/4) 125 parts by weight, γ-methacryloxypropyltrimethoxysilane 40 parts by weight, trimethylolpropane trimethacrylate 50 parts by weight, 2,5-dimethyl-
2,5-di (t-butylperoxy) -hexyne-3
Add 2 parts by weight and 250 parts by weight of acetone, mix by rotating the ball mill for 1 hour, and dissolve uniformly,
A dispersed liquid matrix composition was obtained.

<Preparation of Specimen> 181 style glass fiber fabric (KS1581;
Kanebo Glass Co., Ltd.), and then use a squeeze roll to remove excess matrix,
5 minutes in a hot air circulating dryer to evaporate the acetone,
A fiber reinforced prepreg having a matrix composition content of 50% by weight was produced.

Using one layer of this prepreg,
A lightweight fiber-reinforced ceramics having a thickness of 0.32 mm was manufactured by hot pressing for 15 minutes under the condition of 3.5 kg / cm ² .

When the specific gravity of the test piece was measured by the Archimedes method using ethanol, it was 1.95.
Met.

Since the conventional glass fiber and / or phenol resin has a specific gravity of about 1.9, it was confirmed that the specific gravity of the lightweight fiber reinforced ceramic sheet is equivalent to that of the fiber reinforced plastic.

<Heat Shielding Test> The opening shown in FIG. 1 is covered with a shielding plate, and the opening of the electric furnace 1 which has been heated to 800 ° C. in advance is closed instead of the shielding plate. As described above, the light-weight fiber-reinforced ceramic sheet (hereinafter simply referred to as a cured body) 2 was attached. At this time, as shown in FIG. 1, the thermocouple A is attached so as to be in contact with the surface of the hardened body 2 opposite to the electric furnace 1, and the other thermocouple B is attached to the hardened body 2 of the electric furnace 1. I set it aside so that it would touch the surface.

Immediately after closing the opening of the electric furnace 1 with the hardened material 2, the temperature change inside the electric furnace 1 and outside the electric furnace 1 was measured by the thermocouple A and the thermocouple B.

The measurement results are shown in FIG.

Comparative Example 1 <Preparation of Matrix Composition> Instead of using 100 parts by weight of alumina powder and 400 parts by weight of zeolite,
A matrix composition was obtained in the same manner as in Example 1 except that 400 parts by weight of alumina powder (average particle size: 0.4 μm) and 200 parts by weight of titanium oxide powder (average particle size: 0.4 μm) were used.

<Preparation of Specimen> An inorganic fiber reinforced prepreg having a matrix content of 60% was prepared in the same manner as in Example 1 using the matrix composition, and the inorganic fiber reinforced prepreg was used to carry out the above operation. A ceramic sheet was prepared in the same manner as in the example, and the same evaluation test as in Example 1 was conducted.

When the specific gravity of the test piece was measured by the Archimedes method using ethanol, it was 2.46.
Met.

<Heat Shielding Test> A heat shielding test was conducted on the ceramic sheet in the same manner as in Example 1.

The test results are shown in FIG.

According to FIGS. 2 and 3, the temperature difference between the outside and inside of the electric furnace was 210 ° C. in Example 1 and 170 ° C. in Comparative Example 1.

From the above, it was confirmed that the lightweight fiber-reinforced ceramics of the present invention have excellent heat shielding properties.

[0090]

According to the present invention, it is possible to provide a lightweight fiber reinforced ceramic having a high heat shielding property and being as lightweight as a conventional glass fiber reinforced resin.

Since the lightweight fiber-reinforced ceramics of the present invention have been reduced in weight to the same extent as the conventional glass fiber-reinforced resin (FRP), it is difficult to apply the fiber-reinforced ceramics due to the problem of increased weight in the prior art. By applying this lightweight fiber-reinforced ceramics to existing heat-resistant members or devices, such members,
It is possible to reduce the weight of a device such as a nozzle of an aircraft engine or a plug of an aircraft engine.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a cross section of an electric furnace used for measurement in an example of the present invention.

FIG. 2 is a graph showing measurement results of a heat shield property test in Example 1 of the present invention.

FIG. 3 is a graph showing a measurement result of a heat shielding property test in Comparative Example 1 of the present invention.

[Explanation of symbols]

1 ... Electric furnace, 2 ... Hardened body, A ... Thermocouple, B
···thermocouple

Claims (4)

[Claims] 1. The following components (A), (B) and (C)
Prepreg obtained by impregnating or heat infiltrating a liquid or sheet of a matrix composition containing the component, the component (D), the component (E), and the component (F) into a product of inorganic fibers or laminating it in a sheet form or Molded, temperature 120 ℃ ~ 25
A lightweight fiber-reinforced ceramics, characterized by being heated and pressed under conditions of 0 ° C. and a pressure of 2 to 10 kg / cm. (A) component; fine powder of metal oxide having an average particle size of 1 μm at the maximum; (B) component; soluble siloxane polymer having a double chain structure; (C) component; at least ethylenically unsaturated double bond 1
A trifunctional silane compound contained in an individual molecule, (D) component; organic peroxide, (E) component; at least two ethylenically unsaturated double bonds.
Radical-polymerizable monomer in individual molecule, component (F); zeolite 2. The (A) in the matrix composition.
The blending amount of the components is 50 to 250 parts by weight, the blending amount of the component (B) is 80 to 170 parts by weight, and the blending amount of the component (C) is 25 to
125 parts by weight, the compounding amount of the component (D) is 1 to 4 parts by weight,
25 to 125 parts by weight of component (E), and (F)
The lightweight fiber-reinforced ceramics according to claim 1, wherein the blending amount of the components is 250 to 450 parts by weight. 3. The inorganic fiber is at least one selected from the group consisting of glass fiber, alumina fiber, silica fiber, tyranno fiber, and various fibers containing alumina and / or silica as a main component. And the lightweight fiber-reinforced ceramics according to claim 2. 4. The lightweight fiber-reinforced ceramics according to claim 1, wherein the inorganic fiber product is a tow aligned product or a knitted fabric.