KR100785652B1 - Manufacture method of ceramic foam which superior to insulating effect - Google Patents

Abstract

A method for producing ceramic foam is provided to obtain a heat insulating and noise-absorbing material maintaining its foamed shape during curing and substituting for styrofoam or polyurethane foam, and to improve the cost efficiency and workability. A method for producing ceramic foam having heat insulating and noise-protecting effects comprises the steps of: diluting an animal or vegetable bubbling agent in water; forming a large amount of microbubbles by dispersing the bubbling agent with a high speed dispersion system or foaming system; mixing the foamed product with ceramic powder and additives to obtain ceramic slurry; gelling the ceramic slurry to form a three-dimensional silica network for maintaining the shape of the foamed ceramic slurry; and heating the foamed ceramic slurry to remove water therefrom and to fuse the water dispersible resin(emulsion resin, powder resin) contained in the ceramic slurry, thereby increasing the water resistance.

Description

Manufacture method of ceramic foam which superior to insulating effect}

1 is a schematic process diagram for preparing a foam ceramic through a gelling step of a ceramic comprising an aqueous solution foamed by a foaming agent, a silicate and an additive.

Figure 2 is a photographic view of the foam ceramic after immersed in water for 30 days to confirm the water resistance of the foam ceramic obtained through an embodiment of the present invention.

The present invention relates to a foamed ceramic manufacturing method excellent in heat insulation and soundproofing effect, and more specifically, to include a vegetable or animal foaming agent in an aqueous solution to foam first, and to add a ceramic powder, silicate and additives to the microporous ceramic When preparing in a slurry state, and providing a gelation step to provide a three-dimensional silica network, foaming ceramics manufacturing method to form a large amount of fine foams by drying and curing while maintaining the original shape of the foam without disappearing foams It is about.

The present application does not require a high temperature process or a long time processing process as in the case of manufacturing a conventional foam ceramic or foam cement (ALC), and provides a solid and uniform foam foam ceramic in a short time even at room temperature, and very economical The present invention relates to a foamed ceramic manufacturing method capable of replacing foamed resins such as synthetic resin styrofoam or foamed polyurethane with excellent insulation and sound absorption effects.

Korea is one of the poorest countries in the world, importing almost all of the energy we need from foreign countries. The amount of energy imports is over US $ 50 billion, which is more than 20% of total imports.

Considering Korea's situation as the world's 12th largest trading power and without special energy resources, improving the efficiency of energy use is essential.

In particular, in our reality, where more than 83% of greenhouse gas emissions are generated from energy consumption, the necessity of energy saving is increasing as the 2005 Kyoto Protocol enters into force.

About 30% of the country's total energy consumption is achieved through buildings, so thorough insulation construction is essential to eliminate energy waste factors through buildings, and noise is psychologically impaired in thinking ability, disturbed rest and sleep, and disturbed conversation. May cause hindrances to healthy daily life, physiologically increased fatigue, impatience, difficulty in mental concentration, increased energy consumption for work, decreased gastric juice secretion, cardiovascular effects, decreased salivation, autonomy Insulation and sound insulation are necessary to maintain a comfortable and comfortable living space because it can affect nerves, endocrine system and sleep disturbance. Minimizing the heat energy required in the process of manufacturing insulation and sound insulation for this purpose is itself. It is worth it.

Conventionally, in order to maximize the thermal insulation effect, ceramics or foamed polymer materials with fine porosity are used alone, or porous ceramics formed with air layers and sound absorbing materials that absorb noise are used together to increase the sound insulation effect. This is because the air layer itself formed on the foamable material has excellent heat insulation and sound absorption effects.

Conventional insulation and sound insulation materials use foamed polystyrene, glass wool, foamed polyethylene, polyurethane foam, vermiculite, perlite, urea foam, cellulose insulation, soft fiber board, phenol foam and aerogel and lightweight cement, but foamed In case of polystyrene, it has high insulation and light weight, and has excellent transport and construction. However, it is weak to high temperature and ultraviolet rays with the highest safety operating temperature of 70 ^o C. It has a high risk of ignition or toxic gas in case of fire. In the case of the air layer sealed between the glass fibers as a heat insulating layer, in addition to heat insulation, non-combustible, sound-absorbing, workability, transportability, there is no fear of reducing the effective thickness due to compression or settlement, and lowering the heat insulation by water, but there is no moisture resistance The problem is that the installation of a moisture-proof layer has a problem, in the case of expanded polyethylene After extrusion foaming by the ethylene resin blended with a blowing agent and a flame retardant with a self-extinguishing fused blowing agent lamination of a cooling plate-shaped heat insulating plate, written as prepared in boontong, thermal insulation because the thermal conductivity 0.039 kcal / mh ^o C or less on the average temperature Although it is excellent in effect, it has the problem that it can be fatal to human body due to the emission of toxic gas in case of fire with the maximum safe working temperature of 80 ^o C.

In case of polyurethane, polyol, polyisocyanate, foaming agent, and additives for flame retardancy are the main raw materials.Thermal insulation and sound insulation of foamed polyurethane foam (independent bubble structure), heat resistance (highest safety use) It is suitable for cold storage materials such as refrigeration equipment because it has better thermal insulation than temperature 100 ^o C), but it has the disadvantage of decreasing volume after construction and lowering thermal conductivity. Also, in case of fire, toxic gas is released like other foaming polymer materials. In the case of vermiculite, it is a mica-based ore, which is a porous inorganic material fired at a temperature of 1000 ^o C or more, and has the advantage of insulation, insulation, non-combustibility, soundproofing, and condensation prevention. 900 ~ 1200 ^o C and then pulverized and then fired to the fired? inflation one to consist of small particles of a light-weight spherical type having fine voids therein Lightweight aggregate, and to utilize a heat-insulating material, but the effect on the thermal insulation, thermal insulation, sound absorption, has a problem that it requires more than 1,000 ^o C high energy in order to foam the same minerals and vermiculite or peorayiteu, a thickness of the case of airgel hair 1 manbun Phosphorus structures are entangled like cotton candy, so that the air hole occupies 95% of the total volume, which has the advantage of excellent insulation and soundproofing effects, but it is limited in some high-tech industries due to its high cost.

In the case of lightweight cement, it is possible to provide an economical foam because it uses low-cost cement as a binder, but may cause respiratory diseases and carcinogenesis caused by hexavalent chromium (Cr ^{6 +} ) contained in cement. In order to manufacture lightweight cement, curing must be done in a high-temperature, high-pressure reactor (autoclave), which not only increases the economic burden on the installation cost for manufacturing lightweight cement, but also requires high thermal energy to cure the foamed cement. There is a problem that a long time is required for curing the cement.

As such, the foam material, which has been developed and provided as a heat insulating material and a soundproof material, has a high risk of causing fatal harm to the human body due to the release of toxic gases in the event of a fire, as well as accelerating environmental pollution. In the case of lightweight cement, a large-scale facility system is required, and a high-temperature process or a long-term treatment process is required for the manufacturing process, so that the energy loss is large and the productivity is lowered.

In particular, in the case of foamed ceramics, a large amount of equipment cost is required for forming a mold in order to perform compression molding, or it has a disadvantage of using expensive raw materials such as aerogels. And as a soundproofing material is being applied to a limited number of fields.

In order to solve the above problems, the prior art data that have been studied to provide a porous lightweight structure for insulation and soundproofing materials have been studied. In Korean Patent Laid-Open Publication No. 2006-0099979, acid or amphoteric acid in a liquid sodium silicate is disclosed. Ceramic foam molded by using incomplete gel silicate silica prepared by adding a cargo or amphoteric hydroxide as a binder is proposed a method of manufacturing a structure having a hollow portion formed therein, Korean Patent Laid-Open No. 2006-0092782 One or more kinds of inorganic adhesives including gypsum, pearlite, obsidian, and pine stone alone or in combination, including gypsum, cement, clay, sodium silicate, unfinished gel silicate, and sodium silicate cement. Mixed with other reinforcing materials such as steel fibres, fiber crushed water, paper crushed products (including powder), Produced by mixing the lysosomes (glass wool) or by mounting a wire mesh or synthetic resin network inside to provide a method for providing a durable ceramic foam molding, US Patent Publication 2006-0151903 to provide porosity based on silicate as a main component It discloses a technical configuration to provide a foam by blowing oxygen, nitrogen, air, carbon monoxide, carbon dioxide gas as a carrier gas, Korean Patent Laid-Open Publication No. 2003-0086955 by heating the natural vermiculite at high temperature to expand the pores formed Using a vermiculite and a lauryl alkylbenzene sulfonate-based material, which is a surfactant, the air density is adjusted to about 40 to 50 kg / cm ² , and the resulting bubbles, cement slurry, and expanded vermiculite are mixed and burned in a fire. Non-flammable, lightweight foamed concrete considering the exterior finish and insulation of building without toxic gas emission Propose a sandwich panel.

In Korean Patent Laid-Open Publication No. 2006-0099979 of the patent publication, it is possible to increase the sound-absorbing, sound-absorbing, and heat insulating properties by reducing the weight of the foamed molding, but to provide a ceramic foaming material by using incomplete gel silicate silica having a hollow formed therein as a binder. In this case, an incomplete gel silicate, which is an incomplete gel-like (colloidal) material prepared by adding an acid, an amphoteric oxide or an amphoteric hydroxide to sodium silicate, is simply used as a binder to prepare a general ceramic foam molding. Technological advances aren't great because they're just things to do.

In addition, in 2006-0092782 proposed above, it is possible to provide heat insulation by the air layer included in the ceramic, but in order to manufacture foamed ceramics, various rocks including natural materials such as vermiculite, pearlite, obsidian, and pine stone are crushed to a desired size. In addition, since the pulverized particles must be heated to a high temperature of 800 to 1400 ^o C, a large amount of thermal energy is required to manufacture the foamed ceramics, and a lot of equipment costs are required to prepare the foamed ceramic particles. The technical progress is not so great because it is only a mixture of inorganic adhesives including gypsum, cement, clay, sodium silicate, unfinished gel silicate, and sodium silicate cement.

US Patent Publication No. 2006-0151903 of the above patents do not specifically propose any target material, such as ceramic foam, as well as simply carrier gas in the gaseous state, such as oxygen, nitrogen, air, carbon monoxide, carbon dioxide, etc. It is a technical construction that uses an inorganic binder that blows into the medium to form a foam by gas. Therefore, a large-scale facility is required and economic application is difficult.

Korean Patent Laid-Open Publication No. 2003-0086955 of the above patent provides excellent foaming power by surfactants and economics by using cement as an inorganic binder. However, the curing time for forming a cured body of lightweight cement is shown in the examples. This takes a long time of 1-2 days, so productivity is very low and it is also difficult to apply economically.

Therefore, the present inventors are a product for replacing the foaming resin, which is a petrochemical product, with a conventional heat insulating material and a sound absorbing material, by mixing ceramic powder containing silicate and the foaming agent in a predetermined shape in order to avoid fatal injury to the toxic gas during fire. It is an object of the present invention to provide a foamed ceramic article having a structure in which a foaming step is provided, and a gelation step of providing a three-dimensional silica network is provided so that the foamed foam does not disappear at all and the foamed shape is kept intact.

The foamed ceramic article of the present application provides a large amount of fine foamed ceramics in a certain form in a state where high temperature processes are not required as in the case of manufacturing a conventional foamed article, and thus, the foamed ceramics can be manufactured by a simple manufacturing process with excellent insulation effect. It is intended to provide a method.

The present application confirms the results of research that can increase productivity while enhancing the physical properties of foamed ceramics compared to the inventions applied in the process of applying the applicant's prior application (name of the invention: foamed ceramic manufacturing method) to various fields. And the subsequent application, the present invention does not require high temperature during the process of manufacturing a lightweight ceramic foam, and has a good insulation and sound insulation effect that can replace the conventional petrochemical foam resin by a simple manufacturing process in a short time The invention is completed by confirming that a foamed ceramic article can be obtained.

Still another object of the present invention is to use the foamed ceramic article of the present application in the construction field requiring a lightweight support while requiring physical properties of the ceramic and insulation and sound insulation.

The present invention relates to a foamed ceramic manufacturing method excellent in heat insulation and soundproofing effect, and more specifically, to include a vegetable or animal foaming agent in an aqueous solution to foam first, and to add a ceramic powder, silicate and additives to the microporous ceramic When preparing in a slurry state, and providing a gelation step to provide a three-dimensional silica network, foaming ceramics manufacturing method to form a large amount of fine foams by drying and curing while maintaining the original shape of the foam without disappearing foams Has a technical idea of

One embodiment of the present invention for implementing the above technical concept is briefly mentioned, first of all, in order to prepare a foam, a mixture of vegetable or animal foam is mixed with water to dilute and disperse a large amount of the mixture in the mixture. A preliminary foaming step of forming microbubbles; A gelation step of forming a three-dimensional silica network so as to mix silicate, ceramic powder and additives with the preliminary foam to obtain a ceramic slurry mixture in a slurry state so that the mixture maintains the foam shape; In the gelation step, a large amount of micro-bubbles are formed to remove moisture in the foamed ceramic mixture having a predetermined foaming shape, and the water-dispersible resin (emulsion resin, powdered resin) contained in the foamed ceramic is fused by a heat source for water resistance. A heating step for raising; It characterized by comprising a, characterized in that the manufacturing method for obtaining a foamed ceramic excellent in thermal insulation and soundproofing effect.

Hereinafter, a detailed application example for implementing the technical idea of the present application will be described in detail.

The foaming agent that can be used in the preparation of the foam is diluted with water alone or after mixing a foaming agent based on an amino acid system called an animal foaming agent and an alkylbenzene sulfonate type or a sodium lauryl sulfate and an ester thereof called a vegetable foaming agent. Can be used.

At this time, tap water, groundwater, and industrial water may be used without particular limitation, except for water containing a large amount of alkaline earth metals, which may react with silicate in the mixing step as described below.

The foaming agent may be advantageous to use an animal foaming agent in order to maintain the foamed foam for a long time without foaming, it may be advantageous to use a vegetable foaming agent to avoid the odor generated by the foaming agent itself during the foaming process.

The addition amount of the foaming agent may be added 0.1 to 10 parts by weight based on 100 parts by weight of water, preferably 0.25 to 8.5 parts by weight, more preferably from 0.5 to 7.5 parts by weight, it is advantageous to mix the foaming agent When the content is less than 0.1 parts by weight, the foaming power is low, so it is unlikely that a fine porous bubble is formed. When the foaming agent is diluted to more than 10 parts by weight, a large amount of fine bubbles can be formed, but the foaming agent is Since it is composed of organic materials, not only the bonding strength with ceramic powder is lowered, but also a large amount of toxic gas may be generated due to thermal decomposition of the foaming agent in the event of a fire.

The foaming step is not particularly limited, and it is irrelevant if the solution provided by the foaming agent dilution step can generate a fine amount of bubbles. The foaming step may use a foaming method using a dispersing force of the rotary blades mounted from the shaft of the motor or a foamer equipped with a compressor. If a small amount of foaming agent is required, foaming using the rotary blades mounted from the shaft of the motor is required. It is advantageous to use the process, and it is advantageous to use a foamer equipped with a compressor if a large amount of foaming agent is required.

When using a rotor blade mounted from the shaft of the motor, a rotation speed of 500 to 12,000 rpm can be used, and a mixer, a resolver, a home mixer may be included, and a compressor ( When using a foaming machine equipped with a compressor, it is possible to use a large amount of uniform and fine air, which can be used by adjusting the density of air bubbles generated by applying air pressure by the compressor.

The mixing step does not place a large limit except that the bubbles formed in the pre-expanding step is uniformly mixed with the ceramic powder, silicate and additives, and is uniformly mixed so as to remain in the slurry state by the mixer. When the ceramic powder is based on 100 parts by weight, it is advantageous to mix 20 to 160 parts by weight of silicate, preferably 40 to 140 parts by weight, and most preferably 60 to 110 parts by weight. When contained in parts by weight, even if the gelation step of providing a three-dimensional silica network provides a low bonding strength, it is highly likely that the foamed ceramic foam to sink to the original slurry, 140 parts by weight of silicate If it contains more than that, it can provide foam ceramic with excellent bonding strength. It is preferable to add it in the above ratio because of the low economic efficiency.

At this time, the slurry state is advantageous to maintain the viscosity of 5,000 ~ 200,000 cps, preferably 15,000 ~ 180,000 cps, more preferably 35,000 ~ 160,000 cps, most preferably 50,000 ~ 150,000 cps Advantageously, when the viscosity is 5,000 cps or less has the advantage that the low viscosity, finely foamed ceramic slurry is likely to flow into the mold complex shape, but because of the low viscosity it is highly likely to be defoamed, the technical idea of the present invention If the viscosity is not more than 200,000 cps, the fluidity is low, and it is preferable to maintain the above-mentioned viscosity range because it does not provide a slurry mixed at the corners of the mold shape and also cannot provide a large amount of microfoam. .

The silicate is not particularly limited except that it is dissolved in water or dispersed uniformly, and is selected from one to four types of solution sodium silicate or powdered sodium silicate, calcium silicate, lithium silicate, and sodium aluminum silicate. It is advantageous to use 1 type or 1 type or more, and it is advantageous to use 1 type-4 types of solution type sodium silicate, potassium silicate, or sodium aluminum silicate, More preferably, 1 type-4 types Sodium silicate and sodium aluminum silicate are advantageous, and most preferably it is advantageous to use three kinds of sodium silicate. Potassium silicate and lithium silicate generally have excellent bonding strength and water resistance when the final foamed ceramic of the present invention is prepared. It can provide excellent foamed ceramics, but has the disadvantage of being expensive, and is generally used for sodium aluminum silicate. Although it is inexpensive, the silicate is a combination of aluminum and silicon together, so the relative silica content is reduced, so it is somewhat less than the technical idea to provide a foam ceramic having excellent bonding strength of the present invention, and powdered sodium silicate is clearly dissolved in water. The heat source is required for a long time or for a long time, and one type of sodium silicate (mole ratio of SiO ₂ / Na ₂ O: 2.1 to 2.3) of one to four types of solution sodium silicate has a viscosity of 100,000 cps or more. As it is very large, there is a disadvantage in that the binding force may be relatively low as water must be supplied in order to adjust the slurry state. In particular, in winter, the workability is very high and the workability is very low. sodium silicate two kinds of (SiO ₂ / Na ₂ O of the mole ratio: 2.4 ~ 2.6) provide more than one kinds of the amount of silica sol when the May, but the viscosity is high as substantially to 10,000 ~ 50,000 cps 2 jong also difficult to control the flow of accurate silicate, sodium silicate four kinds of (SiO ₂ / Na ₂ O of the mole ratio: 3.4 ~ 3.6) In case of the large amount It is possible to create three-dimensional silica network, and it is very convenient to control ceramic minerals in slurry state due to its relatively low viscosity, but it is difficult to purchase because it is not produced domestically, and it is expensive. Sodium silicate 3 species (mole ratio of SiO ₂ / Na ₂ O: 3.15 ～ 3.30) is not easy to buy because it is inexpensive and is the most silicate produced by domestic silicate manufacturers. Therefore, in consideration of economics and productivity, it is most preferable to use three kinds of sodium silicate.

The ceramic powder is elvan, loess, olive, kaolin, silicate, silica mineral, diatomite, wollastonite, pyrophyllite, dolomite, lithium minerals. ), Magnesite, Bauxite, Bentonite, Pumice, Borate, Serpentine, Acid clay, Iron Oxide, Garnet ), Carbonate Minerals, Attapulgite, Sepiolite, Nephrite, Apatite, Illite-Mica, Feldspar, Perlite , Vermiculite, Zeolite, Barite, Talc, Diatomaceous earth, Graphite, Hectorite, Clay Minerals, Zirconium Minerals ), Titanium minerals, tourmaine (tourmaline), fume silica, Aerogel, fly ash, blast furnace slag powder may be configured to use one or more selected from one or more selected.

The particle size of the ceramic mineral is advantageously as small as possible in order to provide a fine foam between the ceramic particles and the particles, it is possible to use a size of 5 nm ~ 400 ㎛, preferably a particle size of 20 nm ~ 250 ㎛ It is advantageous, and most preferably, the particle size of 50 nm to 50 μm is advantageous, and the size of 5 nm or less is unlikely to produce fine particles of several nm using a grinder except for aerogels, and also has a raw material cost. Due to its high price, its price competitiveness is low, so it can be used only in some special fields. Ceramic powder with a size of 400 μm or more has a small specific surface area, which decreases the bonding strength due to the gelation step, and at the same time, a large amount between powder and powder. Using a ceramic mineral having a particle size in the above range because the rate of formation of fine foams is low It is preferred.

The additive may include a sound absorbing material having a strength reinforcing agent to enhance the strength of the foamed ceramic or a water reinforcing material for increasing the water resistance, and a metal oxide or fiber may be used as the sound absorbing material having a strength reinforcing agent, and to increase water resistance. Water-resistant reinforcing agent may be added to water-dispersible polymer resin or polymer resin powder bar, the strength enhancer of the metal oxide does not need to be intentionally added because the expanded ceramic of the present invention consists of a metal oxide, ceramic powder and powder The fiber is filled in between and can further enhance the bonding force, as well as the sound-absorbing effect by the sound absorbing material of the fibrous form.

Strength reinforcing agent in the present invention, since the foam is formed at room temperature, there is no big limitation except that it is composed of fibers to further increase the strength of the foam, any of natural fibers or artificial fibers can be used, in the case of natural fibers May include cellulose-based fibers (seedling fibers, bast fibers, salt fiber, fruit fibers), staples, or filament-like protein-based or mineral-based fibers, artificial fibers are organic fibers (regenerated fibers, semi-synthetic fibers, synthetic fibers) ) And inorganic fibers (metal fibers, glass fibers, rock fibers, slag fibers, carbon fibers) may be included.

The fiber thickness of the sound absorbing material having the above-mentioned strength reinforcing agent is advantageously 3 to 50 µm, preferably 5 to 25 µm in thickness, and most preferably 5 to 10 µm in thickness, having a thickness of 3 µm or less. Although the fiber has the advantage of being smoother in appearance and softer to the touch due to the characteristics of the fiber, it has excellent physical properties and high value in use.In addition to glass fiber, the fiber produced from natural fiber and artificial fiber has a thickness of 3 μm or more. Since it has a disadvantage of lacking the option to add fiber, fiber having a thickness of 50 μm or more has a disadvantage in that it is not smooth in appearance and generally has a disadvantage in that it is inferior in strength to fine fibers. Preference is given to using fibers.

The fiber length of the sound absorbing material having a strength reinforcing agent is advantageously 1 to 50 mm, more preferably 5 to 35 mm, and most preferably 10 to 25 mm, and the fiber length is 1 mm or less. The length of the fiber connection between the microporous ceramic powder of the three-dimensional silica network formed in the gelling step of the invention has a disadvantage that the bonding strength is not so large, uniformly with the ceramic of the fiber and slurry form in the mixing step Although it should be dispersed, it is preferable to use fibers having a length in the above range because the fibers are entangled with each other when they are 50 mm or more and thus inhibit the physical properties of the foamed ceramics.

The amount of fiber added as a sound absorbing material having a strength enhancer of the foamed ceramic is preferably 1 to 20 parts by weight based on 100 parts by weight of ceramic powder, more preferably 2.5 to 15 parts by weight. , It is advantageous to include 5.0 to 10 parts by weight most preferably, the addition of less than 1 part by weight has the disadvantage that the reinforcing effect of the foamed ceramic structure is not high, and when more than 20 parts by weight is added, the reinforcing effect is relatively Although it has an advantage of increasing, it is difficult to uniformly mix the ceramic powder and the fiber in the mixing step, and it is preferable to add the amount in the above range because it has a disadvantage in that the economy is inexpensive since the fiber is generally expensive.

The water reinforcing agent to increase the water resistance can be used to include water dispersible polymer resin or fine powder polymer resin bar, in the case of water dispersible polymer resin does not have a big limitation except that the polymer resin is uniformly dispersed in water And, water-dispersible acrylic, vinyl acetate, alkyd, melamine resin, styrene butadiene rubber (Solution Styrene Butadiene Rubber) may be included, the amount of the water-dispersible polymer resin is 1.0 ~ based on 100 parts by weight of ceramic powder It is preferable to include 25 parts by weight, more preferably 2.5 to 25 parts by weight, most preferably it is advantageous to add 5.0 to 15 parts by weight, when added to 1.0 parts by weight or less between the particles of the foamed ceramic It has a disadvantage in that the water resistance is not large because the role of seeding sufficient polymer film is small. 2 When added to more than 5 parts by weight has the advantage that the water resistance considerably increases, but it is advantageous to add the proper concentration suggested above because it has the disadvantage that it can be fatal to the human body by releasing a large amount of toxic gas due to polymer decomposition in the event of fire. Do.

In the case of fine powder polymer resin, polyethylene terephthalate (PET), low or high density polyethylene (PE), vinyl chloride resin (PVC), polymethyl methacrylate (PMMA), polystyrene (PS), polypropylene (PP), ethylene vinyl Preferably, the powder selected from acetate (EVA), polyurethane (PU), and polycaprolacton contains 0.5 to 15 parts by weight based on 100 parts by weight of ceramic powder, and more preferably 2.5 to 12 parts by weight. It is advantageous to add, and most preferably, it is advantageous to add 5.0 to 10 parts by weight. When it is added to 0.5 parts by weight or less, it has a disadvantage in that the water resistance is not large because the role of seeding sufficient polymer film between the particles of the foamed ceramic is small. However, when added to more than 15 parts by weight has the advantage that the water resistance considerably increases, but the water-dispersible polymer resin As it has a disadvantage in that a large amount of toxic gas due to the decomposition of the polymer may be fatal to the human body in the event of a fire, it is advantageous to add the proper concentration suggested above. Particles of the fine powder polymer resin may be a fine powder capable of a size, specifically, a powder in the range of 0.1 μm to 0.5 mm may be used, preferably in the range of 0.5 μm to 0.1 mm, more preferably 5 to 50 mm. It is advantageous to maintain the range of μm. If the size of the powder particles is less than 0.1 μm, the specific surface area becomes larger and the possibility of dispersing in water increases, but it is inconvenient to work due to the dust by fine particles, and the water resistance for fine powder polymers. As a reinforcing agent to increase the viscosity, it has a disadvantage of low economical efficiency, and if it exceeds 0.5 mm, the specific surface area is small and the size of the particles is large, which causes a relatively low probability of uniformly fusion to the ceramic powder. Therefore, it is advantageous to use a powder resin having the size of the proposed particle.

The gelation step of the present application is a process for providing a three-dimensional silica network to the ceramic slurry of the micro-bubbles already formed in the foaming step and the mixing step, the foam does not disappear at all and is cured while maintaining the foamed shape as it is, a large amount of fine The foam is formed so that a high temperature is not required as in the case of manufacturing a conventional foam ceramic, and it is possible to provide a foam ceramic having a constant shape.

The method for forming a three-dimensional silica network herein comprises a slurry of silicate and ceramic in a slurry form containing carbon dioxide (CO ₂ ), a source of acid, bicarbonate, glyoxal , Ethylene glycol diacetate (ethylene glycol diacetate) can be formed by mixing or depositing, a detailed example of the gelling step is as follows.

When carbon dioxide (CO ₂ ) or dry ice is penetrated uniformly into the foamed slurry-type mineral ceramics, the foamed mineral ceramics already containing silicates react with acid (acid), carbon dioxide (carbonic acid gas) and bicarbonate gas. As the chemical balance is broken in the sol state as in the case of 1 to 3, the particles are entangled with each other to form a network of three-dimensional silica due to the gelation of silicate and at the same time maintain the solid state, and the inorganic binder (Binder) As it serves as it will maintain the foamed shape.

M ₂ O · nSiO ₂ + CO ₂ ----> nSiO ₂ (silica gel form) + M ₂ CO ₃

(M = Na, K, Li)

(n = 2 to 4)

M ₂ O · nSiO ₂ + H ₂ SO ₄ ----> nSiO ₂ (silica gel form) + M ₂ SO ₄

(M = Na, K, Li)

(n = 2 to 4)

M ₂ O · nSiO ₂ + LHCO ₃ ----> nSiO ₂ (silica gel form) + M ₂ CO ₃ + LOH

(L = Na, K, NH ₄ )

(M = Na, K, Li)

(n = 2 to 4)

When carbon dioxide is a source for forming a three-dimensional silica network, carbon dioxide gas or dry ice stored in a gas cylinder can be used. When using carbon dioxide gas stored in a gas cylinder, the amount of carbon dioxide injected can be arbitrarily controlled by a pressure regulator. It can be injected at high pressure, which is advantageous when the foam forms a three-dimensional silica network in a thick or short time, and is relatively thin in foam or dry ice to form a three-dimensional silica network over a long time. However, when using dry ice as a source, care should be taken to avoid direct contact with the foam, since moisture-containing foam may break the network of three-dimensional silica due to freezing or reduce the bonding strength.The.

If the source for forming a three-dimensional silica network is an acid, the silicate-containing foam may be deposited in an acid diluted with water or mixed with a slurry in the form of a slurry containing silicate. When deposited on a dilute acid solution diluted for 2 to 10 seconds, neutralization is formed and a network of three-dimensional silica is formed. In this method, the rate at which acid penetrates into finely foamed ceramic slurry is increased. As relatively slow, slurries of up to 1 cm are suitable for forming a three-dimensional network.

When mixing acid with porous slurry of silicate and acid, three-dimensional silica network can be formed within 10 seconds. For this, it is possible when the pH range of slurry mixed with acid is 5-9, and 1 minute. When the above three-dimensional silica network is required, it is possible if the pH is outside the range of 5-9, and the acid used here is hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, citric acid, maleic acid, oleic acid. Among them, one or more acids are selected, and it is advantageous to use sulfuric acid, acetic acid and citric acid, which are inexpensive and can minimize environmental pollution. The dilution amount of the acid is the total weight of water. Is preferably from 2 to 25 parts by weight of dilute acid, more preferably from 2.5 to 20 parts by weight, most preferably 4.0 Since 15 parts by weight is advantageous, when acid is diluted to 2 parts by weight or less, it takes a long time to gel the alkaline silicate contained in the foam while neutralizing, and the acidity exceeds 25 parts by weight. When it is high, it is difficult to control the three-dimensional silica network, and rather it inhibits gelation formation by acid, and in the process of drying the excess acid remaining in the foam during the drying process of the present invention, It is appropriate to mix the above-mentioned addition amount because it causes respiratory diseases.

When the source for forming the three-dimensional silica network is bicarbonate, any one selected from sodium bicarbonate, potassium bicarbonate, and ammonium bicarbonate, or a mixture thereof may be used, and the solution of the bicarbonate itself in powder or water is diluted. Can be mixed with or deposited with the ceramic slurry provided in the foaming step. In the case of ammonium bicarbonate in the bicarbonate, the poisonous odor of ammonia gas or ammonia water is leaked after the final reaction, which is harmful to the human body, and the price of potassium bicarbonate is bicarbonate. Since it is more expensive than sodium, it is advantageous to use sodium bicarbonate, which is as inexpensive as possible and does not cause environmental problems, and the amount of bicarbonate used is a stoichiometric amount that can react with the silicate contained in the foam and cause gelation. Soluble in water or shaking When used, gelation can be induced by a uniform three-dimensional silica network.

Glyoxal and ethylene glycol diacetate are suitable when the source for forming a three-dimensional silica network is relatively needed. For example, the reaction between ethylene glycol diacetate and silicate can be seen. Same as 4.

The slurry in the form of a slurry containing silicate is cured through a first reaction and a second reaction. The first reaction is a hydrolysis reaction, in which EGDAc (ethylene glycol diacetate) is used in the presence of alkali in silicate (1). Hydrolyzes to form ethylene glycol (EG) and acetic acid.

H ₃ C-COO-CH ₂ -CH ₂ -OCO-CH ₃ (EGDAc) + 2H ₂ O → OH-CH ₂ -CH ₂ -OH (EG) + 2CH ₃ COOH (acetic acid)-(1)

Subsequently, as shown in Equation (2), a three-dimensional silica network is gradually developed by gelation reaction. That is, the silicate reacts with acetic acid, producing sodium acetate and an insoluble silicate gel.

M ₂ O · nSiO ₂ + 2CH ₃ COOH → 2CH ₃ COOM + nSiO ₂ (silica gel form) + H ₂ O- (2)

(M = Na, K, Li), (n = 2 to 4)

In the heating step, the water-dispersible polymer resin or fine powder polymer resin of the water-reinforcement agent is removed on the foamed ceramic surface of the three-dimensional silica network to remove water contained in the foamed lightweight ceramics formed up to the gelation step or to improve the water resistance. As a step of coating by fusion, there is no particular limitation except that the moisture in the finely foamed large amount of foam is efficiently bonded to the ceramic surface by heat while efficiently removing as quickly as possible without physical change of the foam. Foamed ceramics that have undergone the gelation step can be dried at room temperature by air, heated by hot air by oven, or rapidly heated by microwave (aka: microwave oven). It is suitable for manufacturing foamable ceramics that do not require much water resistance, and it has the advantage of reducing fuel costs required for the heat drying process by stacking a wide range of foams and drying them with air wind. The disadvantage is that space is required and productivity is low.

The microwave heating method has the advantage that when 2,450 MHz microwave is applied, the water of polar water rises by vibrating heat as much as microwave, and the moisture contained in the object can be removed very quickly. However, it has a disadvantage that a lot of equipment cost is required to dry a large material such as a heat insulating material, it is advantageous to use the hot air heating method by the oven which is most used in the industrial field and the heating temperature using the microwave or hot air heating method Is preferably heated to a temperature of 80 to 250 ^o C, more preferably 90 to 220 ^o C, most preferably 100 to 200 ^o C bar is preferred, heating to a temperature of 80 ^o C In this case, the removal rate of the water contained up to the foaming step is not very high and the water dispersibility for improving the water resistance The polymer resin or the powdered polymer resin has a disadvantage in that it cannot be thermally fused by a heat source on the ceramic surface foamed in the foaming step. When the heating temperature exceeds 250 ^° C., moisture can be rapidly increased. However, since it is much higher than the melting point of fine powder polymer resin, it has the advantage of being easily heat-sealed on the ceramic surface in a short time, so that its water resistance is greatly increased. It is desirable to maintain the proposed heating temperature because it has the disadvantage of weakening.

Hereinafter, the present invention will be described in more detail with reference to the following examples, which are not intended to limit the present invention.

Example 1

As a foaming agent, 2% of water weight is added to the animal foaming agent purchased from Korea Industrial Co., Ltd., a foamed aqueous solution is prepared using a homomixer, and 250 g of ocher powder purchased from Hwangto Myeongga is collected there. 150 g of three kinds of water silica (sodium silicate) purchased from Samhwa Industrial Co., Ltd. were mixed, and a foamed ocher slurry containing silicate was prepared by adding a thickening agent CMC to a viscosity of about 100,000 cps. CO ₂ gas line was inserted therein, and the carbon dioxide gas was purged for 2 minutes to solidify by gelation, and heated and dried in an oven at 100 ^° C. for 2 hours to prepare a foamed ceramic.

Example 2

As a foaming agent, Hanilcon Co., Ltd. vegetable foaming agent (trade name Infomer) was added in the same manner as in Example 1 except that 2% of the water weight was added.

Example 3

Animal foaming agent purchased from Korea Industrial Co., Ltd. is added 4% of water weight, foaming solution is prepared using bubble generator, and 200g of fume silica powder of Dongyang Steel Chemical Co., Ltd. is collected here. 130 g of potassium silicate purchased from Samhwa Industrial Co., Ltd. was mixed therein, and a fumed silica slurry containing silicate was prepared by adding a thickening agent CMC to a viscosity of about 150,000 cps. 50 ml of a 10% sodium bicarbonate solution was added thereto, and the mixture was uniformly mixed at a very high speed. The slurry was solidified by gelation within 13 minutes, heated and dried in a microwave oven for 30 minutes to prepare a foamed ceramic.

Example 4

After making foamed aqueous solution with 4% of the weight of water by using Hanilcon's vegetable foaming agent (trade name infomer), 250 g of ocher powder purchased from Ocher Myeongga Co., Ltd., Samhwa Industrial Co., Ltd. 150 g of three kinds of sodium silicate, 7.5 g of fiber purchased from Dintex Korea, and 5 g of water-dispersible acrylic resin (emulsion acrylic resin) of Ogong Bond Co., Ltd. A yellow clay slurry containing silicate was prepared by adding a thickening agent CMC to 100,000 cps. 100 ml of sulfuric acid solution diluted to 10% concentration was deposited therein for 15 seconds to solidify by gelation, and heated and dried in an oven at 100 ^° C. for 2 hours to prepare a foamed ceramic.

Example 5

After making foamed aqueous solution with 4% of the weight of water by using Hanilcon's vegetable foaming agent (trade name infomer), 250 g of ocher powder purchased from Ocher Myeongga Co., Ltd., Samhwa Industrial Co., Ltd. 150 g of three kinds of sodium silicate, 7.5 g of fiber purchased from Dintex Korea, and 5 g of water-dispersible acrylic resin (emulsion acrylic resin) of Ogong Bond Co., Ltd. A yellow clay slurry containing silicate was prepared by adding a thickening agent CMC to 100,000 cps. As soon as 50 ml of 10% diluted sulfuric acid solution was mixed, the mixture was uniformly mixed at a very high speed and solidified within 8 seconds by gelation, followed by heating and drying in an oven at 100 ^° C. for 2 hours to prepare a foamed ceramic. It was.

Example 6

Animal foaming agent purchased from Korea Industrial Co., Ltd. is added 4% of water weight, foaming solution is prepared by using bubble generator, and 200g of blast furnace slag powder of basic material is collected here and Samhwa Industrial Co., Ltd. 100 g of sodium silicate purchased from Co., Ltd. was mixed, and a blast furnace slag slurry containing silicate was prepared by adding a thickening agent CMC to a viscosity of about 200,000 cps. After adding 25 ml of glyoxal (40%) solution to the mixture, the mixture was uniformly left to stand for 15 minutes, the blast furnace slag slurry was solidified by gelation, and then heated and dried in a microwave oven for 30 minutes to prepare a foamed ceramic. .

Comparative Examples 1-2.

The same procedure as in Examples 1 and 2 was carried out except that the three-dimensional silica network was not formed by CO ₂ .

Comparative Example 3.

The same procedure as in Example 2 was carried out except that three-dimensional silica network gelation with sodium bicarbonate was not performed.

Comparative Example 4.

The same procedure as in Example 4 was carried out except that the sulfuric acid solution diluted to 10% concentration was not deposited for 15 seconds to form a three-dimensional silica network.

Comparative Example 5.

The same procedure as in Example 5 was carried out except that 50 ml of diluted sulfuric acid solution diluted to 10% concentration was not mixed to form a three-dimensional silica network.

Comparative Example 6.

The same procedure as in Example 6 was performed except that 25 ml of glyoxal (40%) solution was not added to form a three-dimensional silica network.

According to Comparative Examples 1 to 6 and Examples 1 to 6, the results for examining the effect of the foamed ceramic having excellent thermal insulation and soundproofing effects of the present invention are shown in Table 1, and in particular, durability of the three-dimensional silica network while maintaining water resistance. In order to examine the put the foamed ceramics of the result obtained in the embodiment of the present invention in water for 30 days was checked for injury.

Experiment Item Water resistance Whether foamed Density (g / cm ³ ) Injury in water (30 days) Example 1 Great Generation of fine bubbles 0.25 30 days or more Example 2 Great Generation of fine bubbles 0.22 30 days or more Example 3 Great Generation of fine bubbles 0.18 30 days or more Example 4 Very good Generation of fine bubbles 0.24 30 days or more Example 5 Very good Large amount of finer 0.23 30 days or more Example 6 Great Large amount of finer 0.25 30 days or more Comparative Example 1 Low No bubble 2.3 Sinking directly into the water Comparative Example 2 Low No bubble 2.4 Sinking directly into the water Comparative Example 3 Low No bubble 1.4 Submerged after 35 minutes Comparative Example 4 Low No bubble 2.4 Sinking directly into the water Comparative Example 5 Low No bubble 2.4 Sinking directly into the water Comparative Example 6 Low No bubble 2.5 Sinking directly into the water

As shown in Table 1, although the silicate is contained in a large amount of fine foamed aqueous solution formed by the blowing agent as in Comparative Examples 1 to 6, the foam disappears unless the gelation step is provided to provide a three-dimensional silica network. While the ceramic structure of the present invention is not made, if the gelation step of providing a three-dimensional silica network in the state of a ceramic slurry containing a silicate of the embodiments 1 to 6 of the present invention in a uniform shape, the foam does not disappear as it is As it was cured while maintaining the foamed shape, a large amount of micro-foams were formed to form a fine air layer between the ceramic structures, thereby confirming that foam ceramics capable of sufficiently exhibiting low-density thermal insulation and sound insulation effects could be confirmed. In addition, even though acrylic resin, which is a water dispersible resin for improving water resistance, is included as in Comparative Examples 4 to 5, when the three-dimensional silica network is not formed, the foamed ceramic slurry is deflected and immediately sinks. Although it was confirmed that the fine air of Al was hardly formed, in Examples 4 to 5, the gel was formed by the three-dimensional network and dried, and the acrylic resin was coated on the ceramic surface, and the water resistance was rapidly increased. It was found that an excellent effect on durability can be exerted by adding.

The present invention is capable of manufacturing a large amount of fine ceramic foam in a variety of shapes to excellent thermal insulation effect, to minimize the damage to life due to the release of toxic gases in the event of a fire, to minimize the manufacturing process and costs to provide a thermal insulation and sound insulation material that is beneficial to the environment It is to obtain a foamed ceramic article having excellent insulation and sound insulation.

The technical idea of the present application does not require a high heat source of 900 ~ 1,300 ^° C in order to manufacture a conventional foam ceramic, and a lot of facility costs such as mold and pressure device for maintaining a constant shape for extrusion, molding It is not necessary to provide an improvement method that does not require much foaming time to form a uniform porous shape, and can provide a foamed ceramic article having excellent insulation and soundproofing effect while minimizing the manufacturing process, as well as further manufacturing process. It is possible to shorten the effect has the effect of providing a foam ceramic that can replace the insulation and sound absorbing material of the conventional petrochemical product Styrofoam or polyurethane foam.

As described above, in the case of manufacturing a conventional foamed ceramic, a high temperature of 1,000 ^o C or more is required, and a huge equipment by extrusion and molding is required, and workability and economic efficiency are very low, whereas animal or vegetable foaming agents are used according to the present invention. After diluting and mixing with water to form a large amount of micro-bubbles, and then mixed with silicate, ceramic powder and additives to provide a slurry state, the gelation step to provide a three-dimensional silica network and to remove the water contained in the micro-foaming body When the heating step is provided, the foam does not disappear even at room temperature and is cured while maintaining a foamed shape, and a large amount of micro-foams are uniformly formed to provide a foamed ceramic having a uniform shape, which is excellent in insulation and sound absorption effect. Economical to replace foaming resins such as polyurethane Of course, the workability is remarkably excellent and there is a very big advantage in producing a foam ceramic excellent in insulation and soundproofing effect.

Claims (16)

In the manufacturing method of foam ceramic having a heat insulation and sound insulation effect, A first mixing step of diluting the animal foaming agent or the vegetable foaming agent in water as a preparation process for achieving foaming; A second foaming step of dispersing the foaming agent obtained in the first mixing step by using a high speed disperser or a foaming machine to form a large amount of fine bubbles; A third foaming slurrying step for obtaining ceramic slurry by mixing silicate, ceramic powder, and additive with the second foaming material; A fourth gelling step of providing a three-dimensional silica network to maintain the shape of the foamed ceramic slurry obtained in the third step; A fifth heating step of removing internal moisture of the ceramic slurry foamed into a predetermined shape through a fourth gelling step and increasing water resistance by fusing the water dispersible resin (emulsion resin, powder resin) contained in the ceramic slurry; Method for producing a foamed ceramic, characterized in that comprises a. The method of claim 1, The foaming agent used in the first mixing step is an animal foaming agent of amino acid type, or is selected from the alkyl foaming agent based on alkylbenzene sulfonate or sodium lauryl sulfate type or ester thereof, the method of producing foamed ceramics, characterized in that used . The method of claim 1, In order to rapidly disperse the foaming agent in the second foaming step, a mixer having a rotational speed of 500 to 12,000 rpm, a dissolver, a homo mixer, or a compressor equipped with a compressor is selected. Method for producing a foamed ceramic, characterized in that to obtain a large amount of fine bubbles by using a device. The method of claim 1, The silicate used in the third foaming sludge stage is selected from one to four kinds of sodium silicate, powdered sodium silicate, potassium silicate, lithium silicate, sodium aluminum silicate, and the method for producing foamed ceramics. The method of claim 1, The ceramic powders used in the third foaming sludge stage include elvan, ocher, olivine, kaolin, silicate mineral, diatomite, wollastonite, pyrophyllite, and dolomite. Dolomite, Lithium Minerals, Magnesite, Bauxite, Bentonite, Pumice, Borate, Serpentine, Acid clay , Iron Oxide, Garnet, Carbonate Minerals, Attapulgite, Sepiolite, Nephrite, Apatite, Illite-Mica Feldspar, Perlite, Vermiculite, Zeolite, Barite, Talc, Diatomaceous earth, Graphite, Hectorite, Clay minerals Clay Minerals, Zirconium Minerals, Titanium Minerals, Tourmarines ne; tourmaline), fume silica, Aerogel, Fly ash, blast furnace slag powder, the particle size of 5 nm ~ 400 ㎛ characterized in that it is used as a powder having a Method for producing foamed ceramics. The method of claim 1, The additive used in the third foaming sludge stage is selected from natural fibers or artificial fibers having a thickness of 3 to 50 μm and a length of 1 to 50 mm, and is used as a strength reinforcing agent that combines strength and sound absorption of the foamed ceramic. Method for producing a foamed ceramic to be. The method of claim 1, The additive used in the third foaming sludge step is selected from water dispersible polymer resin or fine powder polymer resin for water reinforcement of the foamed ceramic. The method of claim 1, Method for producing a foamed ceramic material, characterized in that provided to maintain the viscosity of 5,000 ~ 200,000 cps in the mixing step to provide a slurry (slurry) state by mixing the silicate, ceramic powder and additives in the third foam sludge. The method of claim 1, Stoichiometric amount of gaseous carbon dioxide, solid dry ice, bicarbonate, glyoxal, ethylene glycol diacetate, organic acid, corresponding to the silicate used in the foaming step to provide a three-dimensional silica network in the fourth gelling step A method for producing a foamed ceramic, characterized by mixing and gelling a raw material selected from inorganic acids. The method of claim 1, In the fifth heating step is selected from the room temperature drying with air, hot air drying with an oven (Oven), heating drying using microwaves provided manufacturing method of the foam ceramic. The method of claim 7, wherein The water-dispersible polymer resin used in the third foaming sludge step is selected from water-dispersible resins of acryl, vinyl acetate, alkyd, melamine, styrene butadiene rubber. The method of claim 7, wherein The fine powdered polymer resin used in the third foamed sludge stage is polyethylene terephthalate (PET), low or high density polyethylene (PE), vinyl chloride resin (PVC), polymethyl methacrylate (PMMA), polystyrene (PS). ), Polypropylene (PP), ethylene vinyl acetate (EVA), polyurethane (PU), polycaprolactone (Polycaprolacton) is a method for producing a foamed ceramic, characterized in that it is used The method of claim 9, Bicarbonate used in the foaming step is selected from sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate is a method for producing a foamed ceramic, characterized in that used The method of claim 9, The organic or inorganic acid used in the foaming step is an acid (acid) selected from hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, citric acid, maleic acid, oleic acid is used. The method according to claim 10, Hot air drying by the oven (Oven) or microwave drying heating method is a method for producing a foamed ceramic, characterized in that the drying temperature is provided at 80 ~ 250 ^° C. In the foamed ceramic having insulation and sound insulation effect, A first mixing step of diluting a foaming agent selected from a vegetable foaming agent based on an alkylbenzene sulfonate type or sodium lauryl sulfate type or an ester thereof using an animal foaming agent of an amino acid type to achieve foaming; A second foaming step of dispersing the foaming agent obtained in the first mixing step by using a high speed disperser or a foaming machine to form a large amount of fine bubbles; A third foaming slurrying step for obtaining ceramic slurry by mixing silicate, ceramic powder and additives with the foamed product obtained through the second foaming step; Stoichiometric amount of gaseous carbon dioxide, solid dry ice corresponding to the silicate used in the third foamed slurrying step to provide a three-dimensional silica network to maintain the shape of the foamed ceramic slurry obtained in the third step Gelling step of mixing and gelling a raw material selected from bicarbonate, glyoxal, ethylene glycol diacetate, organic acid and inorganic acid; By removing the internal moisture of the ceramic slurry foamed to a predetermined shape through the fourth gelling step, and the water-dispersible resin contained in the ceramic slurry is fused to provide a fifth heating step for increasing the water resistance to form a foamed shape Foamed ceramics that are cured while being retained.

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