KR100311458B1 - Method of producing organic aerogel microsphere - Google Patents

Abstract

The present invention relates to a method for preparing an organic aerogel in the form of particles, which includes phenolic-peralal, resorcinol-formaldehyde, melamine-formaldehyde, catechol-formaldehyde, phenol-resosocinol-formaldehyde, and fluorolog. Multifunctional monomers such as rucinol-formaldehyde or phenol-formaldehyde are used to prepare sol-emulsion-gel polymerization and solvent substitution in a single process using supercritical carbon dioxide whose solubility varies with temperature and pressure in the vicinity of critical conditions. In addition, the present invention relates to a method for preparing an organic airgel in the form of particles useful as a material for superheat insulation by carrying out the entire process of supercritical drying.

Description

Method for producing organic airgel in the form of particles {Method of producing organic aerogel microsphere}

The present invention relates to a method for producing an organic aerogel in the form of particles, and more particularly, to an organic aerogel such as a phenolic-perforated aerogel, the supercritical carbon dioxide whose solubility varies with temperature and pressure near a critical condition in a reaction continuous phase. To a sol-emulsion-gel method and a method for preparing the particles in a single process through supercritical drying.

Aerogels are materials that have a very large internal surface area due to their low density and high porosity, and were first created by Kistler in 1931. These aerogels can be used as alternative materials, such as conventional CFC blown polyurethane foams or inorganic insulations, which are used as insulation, and can be used as chemical catalysts, ion exchange resins, particle accelerators, noise reduction, piezoelectric elements, insulating glass and release It has a wide range of applications, including controlled pharmaceutical materials.

Conventional foam insulation can not be used for low density of less than 100㎏ / ㎥ because of the relatively high density, because the pore size is limited to lower the thermal conductivity, it was difficult to use as a material for ultra-insulation.

To this end, research into inorganic and organic aerogels is being conducted as a heat insulating material.

Silica-based airgels in inorganic airgels are prepared by supercritical drying through hydrolysis and polycondensation reactions of tetramethoxy silane (TMOS) or tetraethoxy silane (TEOS) under acid or base catalysts.

In the case of using an acid catalyst, linear or slight crosslinked polymers are formed and gels are formed by entanglement thereof, and in the case of a base catalyst, a colloidal gel is formed by the crosslinked polymer.

The silica-based airgel has high porosity and very small pore size (100 nm or less), thereby lowering thermal conductivity.

Among the inorganic airgels, silica airgels with the highest thermal insulation effect have a total thermal conductivity of 0.013 W / m · K at a density of 120 kg / m3 at room temperature and air. Insulation effect is shown.

However, compared with organic aerogels, the thermal insulation performance is generally poor and fragile in terms of structure. In addition, for low density applications, the atomic number should be 8 or less. Silica-based airgel has an atomic number of silicon (Si) of 14, which has higher density and higher thermal conductivity than organic airgel. On the other hand, in the case of aerogels, the atomic number of carbon constituting most of the structure is 6, and the remaining elements of hydrogen and oxygen are 1 and 8, which are suitable for small cell and pore size, and have lower thermal conductivity than inorganic airgel. Because of this, it is more suitable for the application to the super insulation material.

This organic airgel was only recently developed and started in 1984 at the Lawrence Livermore National Laboratory (L.L.N.L) in the United States. Dual resorcinol-formaldehyde aerogels have the most similar structure to inorganic aerogels and use carbon dioxide as a supercritical fluid to extract solvents at low temperature to form aerogels without modification of the structure.

Resorcinol-formaldehyde-based organic aerogels are described in R.W. as disclosed in US Pat. No. 4,873,218 and US Pat. No. 4,997,804. Invented by Pekala, melamine-formaldehyde organic aerogels are also described in R.W. No. 5,081,163, 5,086,085. Invented by Pekala.

A method of preparing such resorcinol-formaldehyde aerogel is briefly shown in FIG. 1A.

U.S. Pat.Nos. 5,476,878 and 5,556,829 disclose organic monogels in monolithic form prepared by the sol-gel method from phenolic-furfural-alcohol solutions.

Since phenolic-perforated aerogels react with carbon dioxide and intimate alcohols, the simplification of the process is omitted by eliminating the process of substituting acetone for the solvent required in the resorcinol-formaldehyde or melamine-formaldehyde reaction as shown in FIG. It can be achieved.

However, the manufacturing of phenolic-perforated aerogels in the form of particles rather than in the monolithic form has many advantages, for example, in the form of particles in energy storage applications can increase the mechanical elasticity of the composite electrode, By using a suitable binder, it can be applied to a low voltage, single cell, such as a 'jelly roll' cell similar to the existing 'AA', 'C', 'D' cells. It can also be used in air filtration and medical applications.

In addition, unlike the monolithic form produced in the batch process, the particle form can be produced through the batch and semicontinuous process, which is advantageous for the actual process application, and the flowability is excellent due to the excellent flowability. It is easy.

The object of the present invention is to prepare organic aerogels in the form of particles rather than monolithic particles through the sol-emulsion-gel method, using supercritical carbon dioxide, which is an environmentally friendly solvent, as a solvent, unlike conventional organic airgel production methods using solvents that are harmful to the environment. It is to provide a method of manufacturing.

It is also aimed at establishing a process in which sol-emulsion-gel polymerization, solvent substitution, and supercritical drying are continuously possible in a single process by using solubility change according to temperature and pressure above the critical condition of supercritical carbon dioxide.

Figure 1a is a schematic process diagram for preparing the conventional resorcinol-formaldehyde airgel particles,

1B is a schematic diagram illustrating a method for preparing phenolic-perforated airgel particles according to the present invention,

Figure 2 is a schematic diagram of the overall experiment of Example 1 of the present invention, ① sol-emulsion-gel polymerization step (80 ℃, 1200 psi, 12 hours), ② solvent replacement step (40 ℃, 2000 psi, 10 times), ③ supercritical drying Step (maintained at 40 ° C, 2000psi for 2 hours, then release carbon dioxide over 1 hour), ④ temperature drop step

3 is a scanning micrograph (× 1500) of organic airgel particles prepared according to Example 1 of the present invention.

4 is a scanning micrograph (× 100000) of an internal structure of organic airgel particles prepared according to Example 1 of the present invention.

In order to achieve the above object, the method for preparing an organic aerogel in the form of particles of the present invention is to add an acid catalyst and a stabilizer to a multifunctional monomer in a high pressure reactor, and then to continuously react supercritical carbon dioxide at 80 to 120 ° C. and 1200 to 1500 psi pressure. Phase to sol-emulsion-gel polymerization for 4 to 24 hours to form an organic gel, cured for 10 to 72 hours, pressurized fresh supercritical carbon dioxide (2000 to 4000 psi) and the temperature to 40 to 60 ℃ It lowers and replaces the alcohol in the gel particles with supercritical carbon dioxide, characterized in that to produce an organic aerogel by discharging the substituted supercritical carbon dioxide.

The present invention will be described in more detail as follows.

In the present invention, the environmentally harmful solvent was replaced with supercritical carbon dioxide, an environmentally friendly solvent, to synthesize phenolic-perforated aerogel particles in the form of particles through a sol-emulsion-gel technique. As a stabilizer, polydimethylsiloxane used in the supercritical polymerization field was used.

The sol-emulsion-gel technique is described in detail as follows. The phenolic-peralal-alcohol solution is suspended in supercritical carbon dioxide and then dispersed using a stabilizer. The advantage of this technique is that, unlike conventional methods, the reaction product does not need to be washed, and there is no need to remove the solvent since there is no solvent participating in the reaction.

The preparation of the organic aerogels according to the invention is carried out continuously in a single process by sol-emulsion-gel polymerization, solvent substitution and supercritical drying.

In the sol-emulsion-gel polymerization step, the solubility of the disperse phase (a mixture of phenolic novolac, peripheral, alcohol, acid catalyst) in supercritical carbon dioxide must be low to disperse to form a gel. On the other hand, in the solvent substitution step, the alcohol inside the gel must be highly soluble in supercritical carbon dioxide so that the alcohol in the gel is replaced with supercritical carbon dioxide, and the aerogel having a three-dimensional continuous phase structure is formed by the supercritical drying of the next step. It can be produced continuously in the process.

In order to achieve the above object, the present invention is characterized by using supercritical carbon dioxide as a reaction continuous phase.

Supercritical fluids are generally defined as materials above the critical temperature T _c and the critical pressure P _c . One of the important advantages of using supercritical fluids in a continuous phase is that the properties of the solvent, such as dielectric constant and solubility, can be controlled by simply changing the temperature or pressure of the system. In addition, supercritical fluids have properties between liquid and gas. Therefore, supercritical fluids, in particular, have the same density as liquid and the same viscosity as gas.

Among supercritical fluids, carbon dioxide has been used as a highly effective continuous phase in many fields for many advantages.

The most direct reason for using a supercritical fluid as a reaction continuous phase that can replace a conventional organic solvent is the chemical and environmental stability of supercritical fluids, especially supercritical carbon dioxide. In addition, carbon dioxide is abundant in its source, which can be said to be infinite.

In addition to the advantages such as stability and economics when the supercritical fluid is used in the reaction continuous phase, it includes the following technical possibilities or innovations; First, the solubility of water or other organic solvents with respect to certain substances is fixed as the system is determined, but for supercritical fluids it can vary considerably with temperature and pressure. It is easy to control the properties of solvents such as dielectric constants by slight changes in pressure or temperature in the vicinity of critical conditions. Unlike ordinary reactions at normal pressure, it is possible to control the physical and chemical properties of the reaction series or to develop a programmable reaction system. It means you can.

Secondly, it is well known that many polymers are swollen by supercritical carbon dioxide, although the solubility to dissolve the synthesized polymer material is not seen. This means that reaction by-products, residual monomers, catalysts, and the like can be effectively removed by a polymerization process and a continuous process. Secondly, it is possible to easily separate these removals from carbon dioxide, thereby improving the environment-friendly environment. This advantage is that in the case of condensation polymer synthesis, if the condensation releasing agent can be dissolved in the supercritical fluid, the condensation reaction of the condensation polymer can be easily and economically produced in a high-molecular weight unlike the general condensation reaction through the complex process by the gel effect. It means that there is.

Third, by introducing a high pressure reaction system to the synthesis of polymers or organic materials prepared through atmospheric pressure reaction, it presents the possibility of synthesizing new polymers different from those produced through atmospheric pressure reaction such as stereoregularity.

In the reaction apparatus used in the present invention, since carbon dioxide is used as a supercritical solvent, a siphon tube is mounted in a carbon dioxide container to eject liquid carbon dioxide, and the liquid carbon dioxide is completely liquefied by passing it through a cooler to pressurize using a high pressure liquid pump. Allow liquid carbon dioxide to enter.

The high pressure reactor is equipped with a jacketed portion of which pressure is sealed up to 4000 psi and a proportional integral derivative controller capable of temperature control from -20 ° C to 200 ° C, a stirrer capable of stirring the thermometer, heater, pressure gauge, safety valves and reactants and the following speeds. It is equipped with a regulator, a tachometer to measure the speed, and a pressurizer to pressurize the new supercritical carbon dioxide at the solvent replacement stage.

In the present invention, phenolic-perforated aerogel particles in the form of particles are synthesized through sol-emulsion-gel technology and supercritical drying using supercritical carbon dioxide, which is an environmentally friendly solvent as a solvent.

More specifically, first, the multifunctional monomer is placed in a high pressure reactor, and an acid catalyst and a stabilizer are added thereto.

Multifunctional monomers include phenolic-peralal, resorcinol-formaldehyde, melamine-formaldehyde, catechol-formaldehyde, phenol-resosocinol-formaldehyde, fluoroglucinol-formaldehyde (Phloroglucinol-formaldehyde), phenol-formaldehyde is selected from one.

The stabilizer may be selected from polydimethylsiloxanes and polydihydroperfluorooctyl acrylates, and the content thereof is preferably 2 to 20% based on the supercritical fluid.

As the acid catalyst, one selected from paratoluene sulfonic acid and phosphoric acid is used. The content of the acid catalyst is preferably 5 to 40% with respect to the monomer.

Then, sol-emulsion-gel polymerization is performed for 4 to 24 hours at 1200 to 1500 psi pressure at 80 to 120 ° C with supercritical carbon dioxide as the reaction continuous phase.

If the reaction temperature is higher than the boiling point of the alcohol, a problem of boiling the reactant may occur. When the reaction pressure is low and the reaction temperature is high, the solubility of phenolic novolac in supercritical carbon dioxide deteriorates, which facilitates dispersion. On the other hand, if the reaction temperature is too low, there is a disadvantage in that it takes a long time to gel. In addition, when the reaction time is shorter than the gelation time of the reactant, a problem may occur in that the sol-emulsion-gel reaction cannot proceed completely.

Thus, when the multifunctional monomer is suspended in supercritical carbon dioxide and dispersed using a stabilizer, there is no need to wash the polymer.

The sol-emulsion-gel polymerization was carried out as described above, followed by curing for 10 to 72 hours, pressurizing the new supercritical carbon dioxide, and lowering the temperature to 40 to 60 ° C. After substitution over 20 times, supercritical carbon dioxide is slowly discharged under isothermal conditions.

In the present invention, after the curing process, pressurize a separate supercritical carbon dioxide, and the process of substituting the alcohol in the organic gel particles formed by lowering the temperature to carbon dioxide, by performing solvent replacement for 10 to 20 times the inside of the gel By replacing the alcohol with supercritical carbon dioxide and drying, an aerogel having a three-dimensional continuous phase structure can be formed inside the gel.

In general, in the preparation of the organic airgel, the solvent inside the gel must be changed to a carbon dioxide atmosphere for supercritical drying. To this end, the conventional resorcinol-formaldehyde aerogel preparation (FIG. 1a) has to fill the liquid carbon dioxide inside the gel, but in the present invention is characterized by filling the supercritical carbon dioxide inside the gel.

Slowly discharging supercritical carbon dioxide under isothermal conditions after the completion of the reaction is to prevent the internal structure of the prepared organic aerogels from being broken, and the discharge time of the supercritical fluid is preferably 0.5 to 5 hours depending on the size of the reactor.

The present invention synthesized a phenolic-perforated aerogel in the form of particles, a method of synthesizing aerogels using supercritical carbon dioxide in the reaction continuous phase. In addition, sol-emulsion-gel polymerization, solvent substitution and supercritical drying were made possible continuously in a single process.

The present invention utilizes the properties of supercritical fluids whose solubility varies with temperature and pressure near critical conditions to form organic gels in a sol-emulsion-gel process on supercritical fluids, continuously dissolving solvents and super As a method for producing solid particles for synthesizing desired organic airgel particles through critical drying, the prepared organic airgel particles have a particle size of 500 nm to 100 µm and a particle size distribution of 90% or more of particles having a particle size of 1-10 µm. The organic airgel particles have a density of 0.03 to 1.0 g / cc, and the internal surface area of the organic airgel is 300 to 1000 m 2 / g.

Looking specifically at the manufacturing method of the phenolic-perforated airgel of the organic airgel according to the present invention, first, phenolic novolac, peroxide, alcohol, acid catalyst and stabilizer are mixed in the high pressure reactor to make a mixed solution.

In this case, one alcohol is selected from heptyl alcohol, octyl alcohol, normal propanol, isopropanol, ethanol and methanol. At this time, the solid content ratio of the mixed solution is preferably 10 to 70% by weight.

Then, the reaction mixture is stirred, it is preferable that the stirring speed is 100 to 500rpm, and the average particle size, particle size distribution, and particle shape vary depending on the type of the stirrer.

After stirring, supercritical carbon dioxide was used as a continuous reaction phase, and pressurized and heated to conduct a sol-emulsion-gel reaction. The reaction temperature was 80 to 120 ° C, and the reaction pressure was preferably 1200 to 1500psi. It should be 4 to 24 hours so that the conversion rate is 70% or more.

It was then cured for 10 to 72 hours, pressurized supercritical carbon dioxide through a pressurizer (pressure 2000-4000 psi), lowered the temperature to 40-60 ° C. and replaced the alcohol in the gel 10-20 times with supercritical carbon dioxide. And, when the supercritical carbon dioxide is slowly discharged, a phenolic-perforated aerogel according to the present invention can be obtained.

A manufacturing process of the phenolic-perforated organic airgel particles according to the present invention is schematically shown in FIG. 1B, and a schematic diagram of the entire experimental conditions of the present invention is shown in FIG. 2.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited by the Examples.

Example 1

After dissolving 13.6 g of phenol resin and 13.6 g of perol in 70 g of heptyl alcohol solvent, the mixture was placed in a high pressure reactor. 2.8 g of a catalyst for producing hydrogen chloride (paratoluenesulfonic acid, manufactured by Junsei, Japan) and 20 g of polydimethylsiloxane as a stabilizer were added thereto, followed by sol-emulsion-gel reaction for 12 hours using supercritical carbon dioxide at 80 ° C as a continuous reaction phase. Then, it was cured for one day to form organic gel particles (pressure 1200 psi). The carbon dioxide was pressurized through a pressurizer (pressure 2000 psi) while the temperature was lowered to 40 ° C. to replace the alcohol contained in the formed organic gel with supercritical carbon dioxide 10 times. Then, supercritical carbon dioxide was slowly discharged into the atmosphere over 1 hour to prepare phenolic-perforated aerogel particles.

The phenolic-perforated aerogel particles produced were dark brown and had a density of 0.03 to 1.0 g / cc. Other solvents may be used isopropanol, normal propanol, ethanol, methanol, octanol. However, when the solvent is different as above, the curing temperature should be different.

The average particle diameter and particle size distribution of the prepared phenolic-perforated airgel particles were measured with a scanning electron microscope (SEM, S-4200, Hitachi, Japan). The measurement result was 90% of the particle distribution with an average particle diameter of 3.5 micrometers and a particle size distribution of 2-5 micrometers.

In addition, the internal surface area was measured with a nitrogen adsorption-desorption apparatus (BET, Sorptomatic 1990, FISONS, UK) of the produced phenolic-perforated airgel particles. The measurement result was an internal surface area of 607.2 m 2 / g.

Example 2

After dissolving 9.09 g of phenol resin and 9.09 g of perol in 80 g of octyl alcohol solvent, the mixture was placed in a high pressure reactor. 1.82.g of a catalyst for producing hydrogen chloride (phosphate, Junsei Co., Ltd.) and 10 g of polydimethylsiloxane as a stabilizer were added thereto, followed by sol-emulsion-gel reaction for 18 hours using supercritical carbon dioxide at 80 ° C as a continuous phase. The particles were prepared and then cured for one day to form organic gel particles (pressure 1200 psi). The alcohol contained in the organic gel formed by pressing supercritical carbon dioxide through a pressurizer (pressure 3000 psi) while lowering the temperature to 40 ° C. was replaced with supercritical carbon dioxide 10 times. The supercritical carbon dioxide was then slowly released to the atmosphere over one hour.

The average particle diameter of the prepared organic airgel particles was 3.2 μm, and the particle size distribution was 1.1% to 5 μm.

The inner surface area of the prepared organic airgel particles was 576.5 m 2 / g.

Example 3

Organic airgel particles were prepared by changing the stabilizer content to 20% with respect to the supercritical fluid using the same process as in Example 1.

The particle size and particle size distribution of the prepared phenolic-perforated aerogels were measured by scanning electron microscope, and the inner surface area was measured by nitrogen adsorption-desorption apparatus.

Example 4

Organic airgel particles were prepared by changing the content of the acid catalyst to 30% with respect to the phenolic novolac using the same process as in Example 1.

The particle size, particle size distribution and internal surface area of the prepared phenolic-perforated airgel particles were measured.

Example 5

Using the same process as in Example 1, the reaction temperature was changed to 120 ° C., the reaction pressure was changed to 1500 psi, and the sol-emulsion-gel reaction was carried out for 12 hours, followed by curing for one day.

The particle size, particle size distribution and internal surface area of the prepared phenolic-perforated airgel particles were measured.

Example 6

Using the same process as in Example 1, 8g of resorcinol and 12g of formaldehyde were dissolved in 223g of propanol and then placed in a high pressure reactor. 1.6 g of a catalyst for producing hydrogen chloride (paratoluene sulfonic acid, Junsei Co., Ltd.) and 20 g of polydimethylsiloxane as a stabilizer were added thereto, and a sol-emulsion-gel reaction was performed at 80 ° C. and 1200 psi for 24 hours, and then cured for one day. Formaldehyde gel particles were prepared. Supercritical oxygen dioxide was pressurized (pressure 2500 psi) while lowering the temperature to 40 ° C., and the alcohol in the formed organic gel was replaced with supercritical carbon dioxide, and slowly discharged into the atmosphere over 2 hours. At this time, the prepared resorcinol-formaldehyde airgel particles showed reddish brown color.

Example 7

Using the same process as in Example 1, 21.44 g of melamine monomer and 18.86 g of formaldehyde were dissolved in 156.64 g of ethanol and then placed in a high pressure reactor. Here, 9.5 g of a catalyst for producing hydrogen chloride (paratoluenesulfonic acid, manufactured by Junsei Co., Ltd.) and 20 g of polydimethylsiloxane as a stabilizer were added thereto, followed by a sol-emulsion-gel reaction at 80 ° C. and 1200 psi for 24 hours, followed by curing for 2 days. Formaldehyde gel particles were prepared. Melamine-formaldehyde airgel particles were prepared by substituting supercritical carbon dioxide (pressure 3500 psi) and lowering the temperature to 40 ° C. to replace alcohol formed in the organic gel with supercritical carbon dioxide and slowly discharging it into the atmosphere over 2 hours. The prepared melamine-formaldehyde airgel particles showed white color.

The average particle size, particle size distribution and internal surface area of the phenolic-perforated airgel prepared according to Examples 1 to 7 are shown in Table 1 below.

Example Average particle diameter Particle Size Distribution (㎛) Internal surface area (㎡ / g) One 3.5 2 to 5 607.2 2 3.2 1.1 to 5 576.5 3 2.5 0.5 to 4 563.4 4 3.1 0.9-5 487.5 5 3.4 0.5 to 4.5 351.3 6 40 10-100 791.0 7 35 10 to 90 438.6

On the other hand, scanning micrographs of the outer shape (× 1500) and the internal structure (× 100000) of the phenolic-perforated airgel particles prepared according to Example 1 are shown in FIGS. 3 and 4, respectively.

The organic aerogels prepared by the sol-emulsion-gel method and supercritical drying using supercritical carbon dioxide as a reaction continuous phase according to the present invention from the results of Table 1 and the attached FIGS. 3 and 4 are supercritical fluids in the form of spherical particles. As the stabilizer content increased, the average particle diameter decreased, and the average particle diameter of the aerogels was almost the same even if the acid catalyst content or the reaction pressure and temperature were changed for the phenolic novolac. In addition, the use of resorcinol-formaldehyde or melamine-formaldehyde as the multifunctional monomer showed a larger average particle diameter than that of phenolic-peral. In addition, the organic airgel prepared in the present invention has an internal surface area of 350 to 800 m 2 / g and has a three-dimensional continuous phase structure.

As described in detail above, in the case of preparing organic aerogel particles such as phenolic-perforated aerogels through the sol-emulsion-gel method and supercritical drying using supercritical carbon dioxide as a reaction continuous phase according to the present invention, the form is It can be produced in a single process as a particle form, there is an effect that does not need to separately wash the result. In addition, since the solubility changes with temperature and pressure near the critical conditions of the supercritical carbon dioxide, which is a continuous reaction phase, all processes such as polymerization, solvent substitution, and drying are performed in a single process, thereby simplifying the process. It can shorten the time and reduce the process running cost. In addition, by preparing the organic airgel in the form of particles can be produced through a batch and semi-continuous process, it is advantageous to the actual process application, excellent flowability, easy to transport, and various application parts. The present invention offers the possibility of using supercritical carbon dioxide in a continuous phase for other condensation polymerizations.

Claims (4)

Dissolving a multifunctional monomer in a solvent in a high pressure reactor, and adding an acid catalyst and a stabilizer thereto to prepare a mixed solution; Sol-emulsion-gel polymerizing the mixed solution for 4 to 24 hours at 80 to 120 ° C. and 1,200 to 4,000 psi pressure using supercritical carbon dioxide as a reaction continuous phase; Curing for 10 to 72 hours to produce organic gel particles; Substituting the solvent in the organic gel particles for 10-20 times at 40-60 ° C., 2000-4000 psi pressure using supercritical carbon dioxide; And Method for producing an organic airgel in the form of particles comprising the step of discharging the supercritical carbon dioxide. The method of claim 1, The multifunctional monomer is selected from among phenolic-peralal, resorcinol-formaldehyde, melamine-formaldehyde, catechol-formaldehyde, phenol-resosocinol-formaldehyde, fluoroclosinol-formaldehyde and phenol-formaldehyde. Method for producing an organic airgel in the form of particles, characterized in that at least one selected. The method of claim 1, Paratoluene sulfonic acid or phosphoric acid is used as an acid catalyst so as to be 5 to 40% with respect to the monomer, and as a stabilizer, it is selected from polydimethylsiloxanes or polydihydroperfluorooctyl acrylates and is 2 to 20% with respect to the supercritical fluid. Method for producing an organic airgel in the form of a particle, characterized in that it is used to. The method of claim 1, The organic airgel has a particle size of 500 nm to 100 μm, a particle size distribution of 1 to 10 μm, 90% or more of particles, and an internal surface area of 300 to 1000 m 2 / g.