KR102316793B1 - Preparation method of needle type metal -silica aerogel composite particle and needle type metal-silica aerogel composite particle prepared by the same - Google Patents

Abstract

The present invention relates to a method for manufacturing a needle-like metal-silica airgel composite particle and a metal-silica airgel composite particle prepared thereby, and the needle-like metal-silica airgel composite particle prepared by increasing the concentration ratio of an acidic solution to a water glass solution. The content of reactive groups that can react with the functionalizing agent in To provide a method for producing a needle-shaped metal-silica airgel composite particle and a metal-silica airgel composite particle prepared thereby.

Description

Needle-type metal-silica airgel composite particle preparation method and needle-type metal-silica airgel composite particle prepared thereby {Preparation method of needle type metal-silica aerogel composite particle and needle type metal-silica aerogel composite particle prepared by the same}

The present invention relates to a method for manufacturing needle-shaped metal-silica airgel composite particles and to needle-shaped metal-silica airgel composite particles prepared thereby.

^{Airgel is an ultra-porous, high specific surface area (≥500 m 2} /g) material with a porosity of about 90 to 99.9% and a pore size ranging from 1 to 100 nm. Since it is a material with a high molecular weight, not only airgel material development research, but also application research in various fields such as insulation materials, ultra-low dielectric thin films for high-integration devices, electrodes for supercapacitors, electrode materials for seawater desalination, catalysts and catalyst carriers, reinforcement materials, filters and coatings, etc. is in progress

Among them, metal-silica airgel composite particles with metal introduced into the airgel are used as additives for polymer resins. Among them, the needle-shaped additive has a certain orientation effect, and the interfacial force between the particles of the additive and the additive There is an advantage in that the mechanical properties can be further improved as the interfacial force between the particles and the polymer resin acts. As such, the needle-shaped metal-silica airgel composite particle can be used as an additive to improve the mechanical properties of the polymer resin, and when used as an additive, to improve the mechanical strength of the needle-shaped metal-silica airgel composite particle, increasing the crystallinity Various methods have been proposed, such as a method, a method of increasing the loading amount of the particles, a method of increasing the aspect ratio of the particles, a method of improving the strength of the particles, and the like.

However, unlike the inorganic material containing silica, the needle-shaped metal-silica airgel composite particle is a kind of organic material in the case of polymer resin. When applied as an additive, there is a disadvantage that it cannot have the effect of improving the mechanical strength of the required level due to the limitation of compatibility due to the different characteristics of the organic and inorganic materials.

Accordingly, in the present invention, in the preparation of needle-shaped metal-silica airgel composite particles used as additives for polymer resins, compatibility with polymer resins is improved, and accordingly, when applied as additives, flexural strength, tensile strength, A novel needle-shaped metal-silica airgel composite particle preparation method that can improve mechanical strength such as impact strength has been developed.

Patent Publication No. 10-2010-0065692 (published on June 17, 2010)

The present invention has been devised to solve the problems of the prior art, and the problem to be solved by the present invention is to improve the compatibility between the needle-shaped metal-silica airgel composite particles and the polymer resin, and when applied as an additive to the polymer resin An object of the present invention is to provide a method for preparing needle-shaped metal-silica airgel composite particles in which mechanical properties such as flexural strength, tensile strength, and impact strength can be improved.

In addition, by using the manufacturing method of the present invention, needle-shaped metal-silica airgel composite particles capable of producing needle-shaped metal-silica airgel composite particles within a short time under mild conditions of low temperature and atmospheric pressure It is to provide a method for producing composite particles.

Another object to be solved by the present invention is to provide a polymer resin comprising needle-shaped metal-silica airgel composite particles prepared by the above manufacturing method.

The present invention is to solve the above problems,

1) adding a water glass solution to the acidic solution in the reactor;

2) forming needle-shaped metal salt particles by adding a solution containing a metal salt after the addition of the water glass solution;

3) preparing a needle-shaped metal-silica wet gel complex by adding a basic catalyst to the solution in which the needle-shaped metal salt particles are precipitated and gelling;

4) drying the needle-shaped metal-silica wet gel composite to prepare needle-shaped metal-silica airgel composite particles; and

5) It provides a method for producing a functionalized needle-shaped metal-silica airgel composite particle comprising the step of reacting the needle-shaped metal-silica airgel composite particle with a functionalizing agent.

In addition, the present invention provides a polymer resin comprising the needle-shaped metal-silica airgel composite particles prepared according to the manufacturing method of the present invention.

In the method for manufacturing the needle-shaped metal-silica airgel composite particles according to the present invention, compatibility with polymer resins and the like can be improved by reacting the needle-shaped metal-silica airgel composite particles with a functionalizing agent. Accordingly, when applied as an additive There is an effect of improving mechanical properties such as flexural strength, tensile strength, and impact strength of polymer resins.

In addition, in the case of the manufacturing method of the present invention, needle-shaped metal-silica airgel composite particles can be manufactured within a short time at low temperature and normal pressure, so the process is simple compared to the conventional manufacturing method, and the production cost is reduced, resulting in productivity and economic efficiency. It has an excellent effect.

The following drawings attached to the present specification illustrate specific embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the above-described content of the present invention, so the present invention is limited to the matters described in such drawings It should not be construed as being limited.
1 is a view schematically showing a binding mechanism of a needle-shaped metal-silica airgel composite particle and a functionalizing agent according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail to help the understanding of the present invention. At this time, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor appropriately defines the concept of the term in order to best describe his invention. Based on the principle that it can be done, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

Functionalized needle-shaped metal-silica airgel composite particle manufacturing method according to an embodiment of the present invention,

1) adding a water glass solution to the acidic solution in the reactor;

2) forming needle-shaped metal salt particles by adding a solution containing a metal salt after the addition of the water glass solution; and

3) preparing a needle-shaped metal-silica wet gel complex by adding a basic catalyst to the solution in which the needle-shaped metal salt particles are precipitated and gelling;

4) drying the needle-shaped metal-silica wet gel composite to prepare needle-shaped metal-silica airgel composite particles; and

5) reacting the needle-shaped metal-silica airgel composite particles with a functionalizing agent.

Hereinafter, the functionalized needle-like metal-silica airgel composite particle manufacturing method of the present invention will be described in detail step by step.

Step 1)

Step 1) according to an embodiment of the present invention is a step for adding the silica precursor of the needle-shaped metal-silica airgel composite particles, characterized in that the water glass solution is added to the acidic solution.

According to an embodiment of the present invention, in particular, sulfuric acid (H ₂ SO ₄ ) may be used as the acidic solution, and in the present invention, more specifically, a 60% aqueous solution of sulfuric acid may be used.

In one embodiment of the present invention, the silica precursor is a water glass solution, tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS) or methyl triethyl orthosilicate (methyl triethyl orthosilicate) ) may be used, but in the present invention, a water glass solution may be used more specifically.

The water glass solution of the present invention represents a diluted solution in which distilled water is added to water glass and mixed _{, and sodium silicate (Na 2} SiO ₃ ) aqueous solution, which is an alkali silicate salt obtained by melting _{silica (silicon dioxide, SiO 2 ) and alkali.} means

On the other hand, in the added water glass solution, the pH is too low due to the acidic solution, so that the gelation reaction does not occur, and the gelation reaction occurs by the basic catalyst added later. It is possible to form particles of type metal-silica composite airgel.

According to an embodiment of the present invention, the concentration ratio of the acidic solution and the water glass solution may be 1:0.1 to 1:0.8, preferably 1:0.2 to 1:0.8, even more preferably 1:0.6 to 0.8 can be In this case, the concentration ratio of the acidic solution and the water glass solution may mean the concentration of the acidic solution: the concentration of the water glass solution, and the concentration of the water glass solution means the concentration of the water glass in the water glass solution, that is, the water glass solution is the concentration ratio in the numerical range. As may be one containing water glass.

According to the present invention, by satisfying the concentration ratio of the acidic solution and the water glass solution, excellent functionalization effect can be seen even with a small amount of functionalizing agent, so that compatibility and dispersibility are improved when applied as an additive to a polymer resin, etc. As the compatibility is improved, mechanical properties such as tensile strength, flexural strength, and impact strength of the polymer resin are improved. On the other hand, when the concentration ratio of the acidic solution and the water glass solution is less than 1:0.1, the content of the water glass solution that can induce the gelation reaction is small. As a result, a lot of surface functional groups capable of reacting with the functionalizing agent are not bound to the surface of the needle-shaped metal-silica airgel composite particles, so a problem of lowering the degree of bonding with the functionalizing agent may occur, and the acid solution and water glass solution When the concentration ratio exceeds 1:0.8, the needle-shaped metal-silica airgel composite particles do not exist in a needle-like shape due to aggregation of the needle-shaped metal-silica airgel composite particles due to excessive gelation in the gelation reaction step described later. There may be a problem that the particles cannot be manufactured.

In addition, the present invention relates to a needle-shaped metal-silica airgel prepared as the concentration ratio of the acidic solution and the water glass solution satisfies the above numerical range, that is, as the concentration ratio of the water glass solution increases, that is, as the concentration of the water glass solution increases compared to the concentration of the acid solution. Since many surface functional groups of the composite particles are formed, it is easy to combine with the functional groups of the functionalizing agent, so that when applied as an additive to a polymer resin, the compatibility and dispersibility are improved, so that the mechanical strength of the polymer resin can be improved. In particular, when the concentration ratio is 1:0.6 to 1:0.8, the above-described effect can be improved with a more significant difference.

In the present specification, the functional group of the functionalizing agent may mean a functional group that reacts with the needle-shaped metal-silica airgel composite particles, for example, may be a reactive functional group derived from an alkoxy group of the functionalizing agent, specifically, FIG. 1 As in, the functionalizing agent may be a hydroxyl group (-OH) generated by hydrolysis.

In addition, in the present specification, the surface functional group of the needle-shaped metal-silica airgel composite particle is a functional group capable of reacting with the hydrolyzed functionalizing agent, specifically, a hydroxyl group (-OH) as shown in FIG. 1 .

Step 2)

Step 2) according to an embodiment of the present invention is a step for forming needle-shaped metal salt particles. After adding a water glass solution to the acidic solution, a solution containing a metal salt is added to increase the ion exchange reaction and reaction temperature. It is characterized in that the crystallization precipitation reaction is performed through the supersaturation step.

Specifically, the acidic solution of step 1), for example, a solution containing a metal salt due to the strong ion exchange ability of an aqueous solution of _{sulfuric acid (H 2} SO _{4 ), for example, a calcium chloride (CaCl 2} ) solution formed by reacting with an insoluble metal salt particle, one example The solubility of calcium sulfate (CaSO ₄ ) decreases as the reaction temperature increases, thereby forming needle-shaped intermediate crystal nuclei.

In the present invention, the needle-shaped metal salt particles prepared by reacting the acidic solution with a solution containing a metal salt may be needle-shaped insoluble metal salt particles. Alternatively, the solution containing the metal salt of the present invention contains the soluble metal salt, and since it is a soluble salt, it may exist in a solution formulation.

On the other hand, with respect to the addition method of the solution containing the metal salt, when a large amount is added at once, _{the concentration of SO 4} ^2- ions in sulfuric acid is rapidly reduced, so sufficient time to generate and grow crystal nuclei cannot be secured. Since it is disadvantageous to the formation of needle-shaped metal salt particles, it is preferable to add it in a dropwise manner.

In addition, in the present invention, the solution containing the metal salt means a solution in which the metal salt is dissolved in a solvent, and the solvent is not particularly limited as long as it can sufficiently dissolve the metal salt. For example, a polar solvent such as distilled water or ethanol may be used. can

Here, the metal salt is a metal chloride, bromide, iodide, nitrate, nitrite, sulfate, acetate, sulfite, acetyl It may include at least one selected from the group consisting of acetonate salt (acetylacetoante) and hydroxide, and the metal is not particularly limited, but may include calcium (Ca), for example, the metal salt is calcium chloride 2 It may include a hydrate (CaCl ₂ 2H ₂ O, aqueous calcium chloride solution). When calcium chloride is used as a solution containing a metal salt, there is an advantage advantageous in the ion exchange reaction rate for forming the initial needle-shaped metal salt particles compared to using other compounds. In addition, the needle-type additive based on calcium (Ca) is harmless to the human body and has eco-friendliness despite its crystalline structure, unlike other needle-type additives. Therefore, it is also used as an alternative exterior material for asbestos and is used as an additive in various fields due to its excellent thermal stability, chemical stability, and dimensional stability. It can be used as a thickener of various materials, and the calcium has a variety of application fields due to its excellent physical properties.

As such, according to an embodiment of the present invention, by reacting an acidic aqueous solution of sulfuric acid with a calcium chloride solution containing a metal salt, needle-shaped calcium sulfate (CaSO ₄ ) particles can be prepared. That is, the needle-shaped metal salt particles of the present invention may preferably be calcium sulfate.

On the other hand, in order to maximize the effect of the present invention as an additive for polymer resin by taking advantage of the acicular shape of the metal-silica airgel composite particle of the present invention, the concentration of the solution containing the reactant acid solution, water glass solution and metal salt need to be properly adjusted. This is because, when the metal-silica composite airgel particles are prepared using an appropriate concentration of the reactant, needle-shaped particles having an aspect ratio more favorable to the polymer resin additive can be formed.

Accordingly, the concentration of the acidic solution and the solution containing the metal salt in the present invention may be each independently 0.5 M to 2.8 M, preferably 0.8 M to 2.0 M, and more preferably 0.8 M to 1.2 M. .

When the concentration of the solution containing the acidic solution and the metal salt is too low, less than 0.5 M, the rate of supersaturation and/or ion exchange reaction with increasing temperature decreases, and the rate of supersaturation or ion exchange reaction is As it slows down, _{non-acicular intermediates such as Ca(OH) 2} may be produced, and the growth of the nuclei of the needle-shaped metal salt particles becomes difficult, so there may be a problem in that uniform needle-shaped metal salt particles cannot be formed, and also , when the concentration exceeds 2.8 M, the higher the concentration, the larger the size of the needle-shaped metal salt particles formed due to the agglomeration phenomenon, and the size of the metal-silica airgel composite particle, which is the final product, also increases. A problem of lowering mechanical properties may occur, and the generation of crystal nuclei of the particles is more dominant than the growth of crystal nuclei, so the needle-shaped morphological advantage can be obtained without maintaining the needle-like shape and forming spherical particles. Problems may arise that do not work.

In addition, the concentration ratio of the acidic solution and the solution containing the metal salt may be 1:0.5 to 1:2, specifically 1:0.8 to 1:1.2, and more specifically 1:1, where the acidic solution The concentration ratio of the solution containing the metal salt and the concentration ratio of the acid solution may mean the concentration of the solution containing the metal salt. In the present invention, it is possible to synthesize the optimal needle-shaped particles when the above concentration ratio is satisfied.

Step 3)

Step 3) according to an embodiment of the present invention is a step for preparing a needle-shaped metal-silica wet gel complex, and a basic catalyst is added to the needle-shaped metal salt particles prepared in step 2).

In one embodiment of the present invention, the basic catalyst may serve to promote and complete the gelation reaction by increasing the pH of the water glass solution added to the reactor.

In the present invention, gelation may be to form a network structure from a silica precursor material, and the network structure is a planar network-shaped structure in which a specific polygon is connected with one or more kinds of atomic arrangement or a specific It may indicate a structure in which a three-dimensional skeletal structure is formed by sharing vertices, edges, faces, etc. of a polyhedron.

Meanwhile, in step 3), as the pH in the reactor is improved, a gelation reaction occurs so that the silica airgel is uniformly bound or coated on the surface of the needle-shaped metal salt particles to form a needle-shaped metal-silica wet gel complex.

At this time, the pH in step 3) may be 4 to 10, preferably 7 to 9, and if it is out of the numerical range, gelation is not easy, or the gelation rate is excessively slow, so there is a risk of lowering fairness, In particular, when a high pH exceeding 10 is formed, there may be a problem in that independent spherical silica airgel particles are formed rather than silica airgel on the surface of the needle-shaped metal salt particles.

In addition, the basic catalyst of the present invention is specifically sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH) ₂ ), barium hydroxide (Ba(OH) ₂ ), ammonium hydroxide (NH ₄ OH), sodium carbonate (Na ₂ CO ₃ ) and magnesium hydroxide (Mg(OH) ₂ ) At least one selected from the group consisting of may be used, and in the present invention, more specifically, ammonium hydroxide, that is, aqueous ammonia solution may be used.

This is because, when a strong base is used, the pH is rapidly increased, so that spherical silica airgel particles are more likely to be formed rather than silica airgel formed on the surface of needle-shaped metal particles. Therefore, in the present invention, ammonium hydroxide having a relatively small base dissociation constant (K) is used to suppress a rapid increase in pH so that the silica airgel is uniformly bonded or coated on the surface of the needle-shaped metal salt particles.

On the other hand, as in the present invention, the gelation reaction of water glass is induced on the surface of the needle-shaped metal salt particles for the following three reasons.

First, when the actual needle-shaped metal is applied to the polymer resin as an additive, if the additive is acidic, it cannot be used because it affects the physical properties of the polymer resin. In order to solve this problem, the additive is made basic by inducing the gelation of water glass on the surface of the needle-shaped metal.

Second, in order to improve the strength of the needle-shaped metal particles in order to reduce the problem that the additive particles are broken by a certain shear force during compounding application, the gelation of the water glass is induced on the surface.

Third, in the case of a needle-like metal, an advantageous effect due to the specific surface area property cannot be obtained, whereas when a gelation reaction is induced on the surface, an advantageous effect due to the specific surface area property can also be secured.

Therefore, the present invention is to prepare a needle-shaped metal-silica airgel composite in which silica airgel is uniformly bound to needle-shaped metal salt particles in order to prepare needle-shaped metal-silica airgel composite particles suitable for use as an additive for polymer resins.

On the other hand, the bond means a chemical bond and/or a physical bond, and preferably, most of the bonds may be made of a physical bond. As an example, the needle-shaped metal-silica airgel composite particle of the present invention may be one in which silica airgel is attached to the surface of the needle-shaped metal particle, in the form of a coating, or the like.

However, when the silica airgel is bonded to the surface of the needle-shaped metal salt particles as in the present invention, when the functionalizing agent is introduced to improve the compounding properties of the polymer resin, etc., the surface of the needle-shaped metal-silica airgel composite particle is mixed with the functionalizing agent. There may be a problem in that the degree of binding is low and an excess of the functionalizing agent is required.

Therefore, when inducing gelation with the water glass solution, in order to form a large number of surface functional groups of the needle-shaped metal-silica airgel composite particles that react with the functional groups of the functionalizing agent, the concentration ratio of the acidic solution and the water glass solution specified above in the present invention is satisfied. it is preferable

According to an embodiment of the present invention, the needle-shaped metal-silica airgel composite particles prepared by the method of the present invention may contain silica in an amount of 10 to 30 wt% based on the total weight. When silica is included at an appropriate level as described above, it may be advantageous because there is an effect of increasing mechanical strength and facilitating density control.

On the other hand, the gelation reaction of step 3) may be accomplished through stirring, and the stirring speed may be 100 rpm to 300 rpm, preferably 150 rpm to 200 rpm.

When the stirring speed is less than 100 rpm, aggregation occurs between the water glass solutions, which may cause a problem that gelation is not performed evenly on the needle-shaped metal salt particles, and when the stirring speed exceeds 300 rpm, sufficient growth time Due to this deficiency, a form with a low aspect ratio is synthesized, and the gelation of the water glass solution is independently performed rather than gelation on the needle-shaped surface, and through this, independent spherical silica can remain.

In addition, in the case of the production method of the present invention, the ion exchange reaction or supersaturation reaction to form needle-shaped metal salt particles in steps 1) and 2) of the present invention and the gelation reaction in step 3) of the present invention are subjected to conditions of high temperature and high pressure. Unlike the required conventional manufacturing method, needle-shaped metal-silica airgel composite particles can be prepared within a short time under conditions of low temperature and atmospheric pressure.

More specifically, the production method of the present invention is 50 to 100 ℃, more specifically 60 to 90 ℃ reaction temperature and atmospheric pressure, more specifically 1 to 5 hours at a pressure condition of 1 to 1.2 bar, more specifically It is characterized in that the needle-shaped metal-silica airgel composite particles are synthesized within a short time of 1 to 3 hours.

On the other hand, 'normal pressure' refers to normal pressure or atmospheric pressure, and refers to the pressure when a high-pressure device such as a separate autoclave is not used, or when the pressure is not reduced or increased.

When an acidic solution of a specific concentration, a solution containing a metal salt, and a water glass solution are used as in the production method of the present invention, it is easier to synthesize needle-shaped particles that can maximize the morphological advantages, so that the needle-shaped particles can be synthesized even under mild conditions of low temperature and atmospheric pressure. This is because it is possible to significantly reduce the overall process time required to prepare metal-silica airgel composite particles of the same type.

Therefore, in the case of the manufacturing method of the present invention, high temperature and high pressure equipment such as a separate autoclave is not required, so production costs can be reduced, and productivity and economy are improved because production is possible by a simple and safer process. When used as an additive for polymer resins by an excellent, uniformly coated silica airgel, dispersibility is increased and a separate surface modifier is not required, thereby reducing production costs.

On the other hand, when the reaction temperature of the production method of the present invention is less than 50 ℃, there may be a problem in that the needle-shaped particles are not properly synthesized or the synthesis rate is too slow, the reaction time increases than the time desired by the present invention, and the reaction temperature When is greater than 100 ℃, the process is complicated and the cost increases, and thus the needle-shaped metal-silica airgel composite particles having excellent productivity and economical efficiency may not be met.

In addition, when the reaction pressure is carried out at a pressure lower than normal pressure, there may be a problem in that the needle-shaped particles are not synthesized properly or the synthesis rate is too slow, the reaction time increases than the time desired by the present invention, and the reaction at high pressure When this is performed, the process is complicated because expensive equipment of high pressure is required, so that the manufacturing cost increases, production efficiency may decrease, and there may be a problem in terms of stability due to the use of dangerous equipment of high pressure.

In addition, the present invention is intended to strengthen the structure of the airgel, and after the completion of the gelation reaction, a basic catalyst is added and left at an appropriate temperature, so that a chemical change can be performed additionally, an aging step can be additionally performed.

In the case of performing the aging step, the basic catalyst induces Si-O-Si bonding in the airgel to the maximum to make the network structure of the silica airgel more robust to further enhance the mechanical stability of the needle-shaped metal-silica airgel composite particles. can In this case, there is an effect of more easily maintaining the pore structure in the drying process to be performed later.

In addition, the aging should be performed in an appropriate temperature range in order to optimally strengthen the pore structure.

Aging of the present invention may be carried out by leaving it at a temperature of 30 to 70 ℃. If the aging temperature is less than 30 ℃, there may be a problem that the aging time is excessively long, leading to an increase in the overall process time, and thereby decreasing productivity. However, there may be a problem in that the cost of raw materials increases.

Step 4)

Step 4) according to an embodiment of the present invention may be a step of preparing the needle-shaped metal-silica airgel composite particles by drying the needle-shaped metal-silica wet gel composite prepared in step 3).

The drying step of the present invention is a step for forming needle-shaped metal-silica airgel composite particles by removing the solvent from the needle-shaped metal-silica wet gel composite, and under a temperature condition of 100 to 190 ° C., atmospheric pressure for 1 to 4 hours. It may be carried out by drying. The atmospheric drying process does not require special high-pressure equipment for high-pressure reaction conditions and supercritical drying, so the process is simple and economical.

In the present invention, the needle-shaped metal-silica airgel composite particles are needle-shaped metal-silica airgel composite particles immediately after drying the wet gel composite, and the needle-shaped metal-silica airgel composite particles before reacting with a functionalizing agent may be.

In addition, the needle-shaped metal-silica airgel composite particles may be, for example, in a powder formulation, and in the case of a powder formulation, excellent reactivity with the functionalizing agent can be secured in the step of reacting with the functionalizing agent to be described later. Specifically, when reacting with the functionalizing agent to be described later, when the needle-shaped metal-silica airgel composite particles are in powder form, they can be most evenly dispersed in the functionalizing agent dispersion, so that the reactivity can be improved.

In addition, the needle-shaped metal-silica airgel composite particles that have undergone step 4) according to an embodiment of the present invention can obtain pores from which moisture is removed through drying, and react with a functional group formed after hydrolysis of the functionalizing agent. Since the surface functional groups of the composite particles may be exposed to the outside, there is an effect of ensuring smooth reactivity when reacting with the functionalizing agent. On the other hand, as the wet gel of step 3) before drying contains a large amount of moisture, the reactor is not sufficiently exposed and side reactions may occur, so that the reactivity between the needle-shaped metal-silica airgel composite particles and the functionalizing agent is reduced Problems can arise.

In addition, the manufacturing method of the present invention may further include any one or more steps of washing and solvent replacement between steps 3) and 4).

The washing of the present invention is to prepare high-purity needle-shaped metal-silica airgel composite particles by removing impurities generated during the reaction. It may be carried out by dilution and stirring for a period of time, and distilled water or alcohol may be used as the washing solvent.

In addition, the present invention may include a step of replacing the solvent before drying in order to prevent shrinkage or collapse of the pore structure in the drying process in addition to the aging step.

Silica wet gel prepared using water glass takes a form in which the pores are filled with water as a solvent, and when the solvent is simply dried and removed, the liquid solvent is vaporized into a gas phase and the high surface tension of water at the gas/liquid interface Due to the capillary force and the difference in solvent extraction rate, it is easy to contract and crack the pore structure, which causes a decrease in the surface area and a change in the pore structure. Therefore, in order to maintain the pore structure of the wet gel, it is necessary to replace water having a high surface tension with an organic solvent having a relatively low surface tension. Accordingly, the present invention may further perform solvent replacement with a polar organic solvent such as ethanol, methanol or isopropanol before drying.

Step 5)

The step 5) according to an embodiment of the present invention is a step of reacting the needle-shaped metal-silica airgel composite particles of step 4) with a functionalizing agent, to prepare the functionalized needle-shaped metal-silica airgel composite particles. , a step of inducing binding of the needle-shaped metal-silica airgel composite particle with the functionalizing agent by reacting the functional group formed after hydrolysis of the functionalizing agent with the surface functional group of the needle-shaped metal-silica airgel composite particle. Metal-silica airgel composite particles may be formed.

In the present invention, the functionalized needle-like metal-silica airgel composite particle may mean a needle-like metal-silica airgel composite particle to which a functionalizing agent-derived group is bonded by reacting with a functionalizing agent, specifically, the needle-like type of step 4) It may mean a needle-shaped metal-silica airgel composite particle functionalized by binding a functionalizing agent-derived group to the surface of the metal-silica airgel composite particle.

In the present invention, the functionalizing agent serves as a coupling agent to improve compatibility with a polymer resin, etc., and the derived group of the functionalizing agent binds to the surface of the needle-shaped metal-silica airgel composite particle to form the composite particle as an additive to a polymer resin, etc. When applied, compatibility with polymer resins, etc. is improved, so that mechanical strength of polymer resins and the like can be improved.

The functionalizing agent according to an embodiment of the present invention is not particularly limited as long as it is a commonly used functionalizing agent, and may be, for example, an alkoxysilane-based functionalizing agent, and more specifically, may be represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1,

R ¹ is a single bond or a substituted or unsubstituted divalent hydrocarbon group,

R ² and R ³ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms,

X is any one substituent selected from the group consisting of a vinyl group, an epoxy group, a glydoxy group, an amino group, a (meth)acryl group, a (meth)acryloxy group, a halogen group and a mercapto group,

a is an integer from 1 to 3.

In Formula 1, the functional group X is a reactive functional group capable of bonding with an organic resin such as polymer resin, and the alkoxy group (-OR ² ) bonded to the silyl group is hydrolyzed and then bonded to the surface of the needle-shaped metal-silica airgel composite particle. It is a reactive functional group that can

Here, the (meth)acryl group may be a methacryl group and/or an acryl group, and the (meth)acryloxy group may be a methacryloxy group and/or an acryloxy group.

Specifically, R ¹ may be a single bond or an alkylene group having 1 to 20 carbon atoms, an arylene group having 1 to 30 carbon atoms, an arylalkylene group having 1 to 30 carbon atoms, or an alkylarylene group having 1 to 30 carbon atoms, and more specifically It may be an alkylene group having 1 to 10 carbon atoms.

In addition, specifically, R ² and R ³ may each independently be an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

In addition, specifically, X may be any one substituent selected from the group consisting of a vinyl group, an epoxy group, an amino group, and a (meth)acryl group.

The functionalizing agent is, for example, vinyl trimethoxysilane, vinyl tris(2-methoxyethoxy)silane, vinyl (3,4-epoxycyclohexyl)ethyltrimethoxysilane, glycidoxy propyl trimethoxysilane, glycidyl Cydoxy propyl methyldiethoxysilane, glycidoxy propyl triethoxysilane, methacryloxy propyl methyldimethoxysilane, methacryloxy propyl trimethoxysilane, methacryloxy propyl methyldiethoxysilane, N-(amino ethyl) -amino propyl methyldimethoxysilane, N-(amino ethyl)-amino propyl trimethoxysilane, N-(amino ethyl)-amino propyl triethoxysilane, amino propyl trimethoxysilane, amino propyl triethoxysilane, It may include one or more selected from N-phenyl-amino propyl trimethoxysilane, chloro propyl trimethoxysilane, and mercapto propyl trimethoxysilane.

The binding mechanism of the functionalizing agent is, as shown in FIG. 1, after the functionalizing agent introduced first is hydrolyzed to convert all alkoxy groups bound to the silyl group into hydroxyl groups (-OH), and then the hydroxyl groups are needle-shaped metal- As silica is hydrogen-bonded with a hydroxyl group present on the surface of the airgel composite particle, the functionalizing agent in which the substituent is converted to a hydroxyl group is adsorbed to the surface of the needle-shaped metal-siliga airgel composite particle. The functionalizing agent in which the substituent is converted to the adsorbed hydroxyl group undergoes a dehydration condensation reaction through a drying process, so that a strong chemical bond can be formed between the functionalizing agent-derived group and the needle-shaped metal-silica airgel composite particle.

According to an embodiment of the present invention, in step 5), 0.1 to 5 parts by weight of the functionalizing agent may be added based on 100 parts by weight of the needle-shaped metal-silica airgel composite particles, and preferably 0.5 to 3 parts by weight may be added. . When the functionalizing agent is less than 0.1 parts by weight, the content of the functionalizing agent is insignificant, and the possibility of contacting the surface of the needle-shaped metal-silica airgel composite particles is low, so binding with the composite particles may not be easy, and when it exceeds 5 parts by weight, the content of the functionalizing agent Even if this is increased, the amount of the functionalizing agent bound to the surface of the needle-shaped metal-silica airgel composite particle does not increase significantly, so unnecessary costs may be consumed due to excessive use, thereby reducing the economic feasibility of the entire manufacturing process.

Since the needle-shaped metal-silica airgel composite particles according to the present invention have a large amount of surface functional groups capable of increasing the reactivity with the hydroxyl groups of the functionalizing agent on the surface, the degree of bonding may be high even with a relatively small amount of the functionalizing agent, Accordingly, when applied as an additive to a polymer resin, the compounding properties are improved.

In addition, step 5) may be performed for 1 to 2 hours at 40 to 60° C. and atmospheric pressure. In the above temperature range, the reaction of the needle-shaped metal-silica airgel composite particles and the functionalizing agent may be smoothly performed.

On the other hand, according to an embodiment of the present invention, in step 5), the functionalizing agent is hydrolyzed, it is put into a high-speed stirring mixer, and the needle-shaped metal-silica airgel composite particle is added and stirred to perform a reaction. (dry treatment method), or, after dispersing the functionalizing agent in a solvent, the reaction may be carried out by adding needle-shaped metal-silica airgel composite particles to the dispersion (wet treatment method), preferably the latter method. have. Specifically, the step 5), 5-1) dispersing the functionalizing agent in a solvent; and 5-2) adding and reacting the needle-shaped metal-silica airgel composite particles to the dispersion in which the functionalizing agent is dispersed.

Specifically, in the step of reacting the needle-shaped metal-silica airgel composite particles with the functionalizing agent, the functionalizing agent is first dispersed in a solvent, and then the needle-shaped metal-silica airgel composite particles are all dried in the dispersion in which the functionalizing agent is dispersed. A reaction using a wet treatment method can be made by adding the .

Here, the solvent is not particularly limited as long as it is a solvent that disperses the functionalizing agent and the needle-shaped metal-silica airgel composite particles and allows the functionalization agent to be hydrolyzed smoothly, but preferably includes water. When water is included as a solvent, hydrolysis of the functionalizing agent is smoothly performed, and there is an effect that the alkoxy group of the functionalizing agent is easily converted into a hydroxyl group.

The surface coating method, which is one of the methods for binding the functionalizing agent, is a method of coating the surface of the inorganic material with a functionalizing agent before adding the inorganic material such as an additive to the organic resin such as polymer resin. There is an advantage of higher efficiency compared to the method of adding at the same time.

The surface coating method is divided into a dry treatment method and a wet treatment method as described above. In the dry treatment method, a solution containing a functionalizing agent is added dropwise or sprayed while stirring at high speed, but the reaction takes a long time, so the efficiency is relatively low. In addition, since a mixing device capable of high-speed stirring is essential, additional manufacturing costs are high, and the degree of binding of the functionalizing agent may vary depending on the mixing device.

The wet treatment method is a method in which an inorganic material is added to a dispersion in which a functionalizing agent in a solvent is dispersed to induce binding to a functionalizing agent-derived group. Since it is to react with the needle-shaped metal-silica airgel composite particle, which is an inorganic material, there is no device limit because a separate device is not required, and the process is relatively simple, resulting in economic synergy. In addition, according to an embodiment of the present invention, when the functionalized needle-shaped metal-silica composite particles are prepared by the wet treatment method, when applied as an additive to a polymer resin, the flexural strength, tensile strength, and impact of the polymer resin, etc. Mechanical properties such as strength may be further improved.

On the other hand, according to an embodiment of the present invention, a drying process may be additionally performed on the functionalized needle-shaped metal-silica airgel composite particles prepared after the functionalizing agent-derived group is adsorbed as described above, and the drying process is described above. It may proceed in the same way as the drying process. During the drying process, moisture may be removed and a dehydration condensation reaction may proceed, thereby forming a chemical bond between the functionalizing agent-derived group and the needle-shaped metal-silica airgel composite particle.

According to an embodiment of the present invention, when manufactured according to the above manufacturing method and included as an additive in the polymer resin, the flexural strength of the polymer resin is 27 MPa or more, the tensile strength is 18 MPa or more, and the impact strength is 45 J Needle-shaped metal-silica airgel composite particles that can be /m or more can be prepared.

Specifically, when the needle-shaped metal-silica airgel composite particles are included as an additive, the flexural strength of the polymer resin is 28 MPa or more, more specifically 30 to 39 MPa, and the tensile strength is 20 MPa or more, more specifically is 20 to 23 MPa, and the needle-shaped metal-silica airgel composite particles that can have an impact strength of 48 to 60 J/m can be prepared.

The needle-shaped metal-silica airgel composite particles can increase dispersibility when applied as an additive to an organic resin by uniformly binding the functionalizing agent, and accordingly, the flexural strength, tensile strength and impact of organic resins such as polymer resins, which are additives Mechanical properties such as strength may be improved.

In addition, according to an embodiment of the present invention, the needle-shaped metal-silica airgel composite particles prepared according to the above manufacturing method and having an aspect ratio of 3 to 30, preferably 5 to 25 may be prepared. In the above aspect ratio, the morphological advantage of the needle-like shape can be best maintained.

In addition, according to an embodiment of the present invention, the needle-shaped metal-silica airgel composite particles prepared by the above manufacturing method are included, and the flexural strength is 27 MPa or more, the tensile strength is 18 MPa or more, and the impact strength is 45 J A polymer resin of /m or more may be provided.

Specifically, the polymer resin has a flexural strength of 28 MPa or more, more specifically 30 to 39 MPa, a tensile strength of 20 MPa or more, more specifically 20 to 23 MPa, and an impact strength of 48 to 60 J/ m, and the flexural strength, tensile strength and impact strength of the polymer resin may be expressed from the needle-shaped metal-silica airgel composite particles prepared according to the manufacturing method of the present invention.

In addition, the polymer resin may be, for example, a thermoplastic resin, and the thermoplastic resin is not particularly limited as long as it is a thermoplastic resin generally used in the industrial field. For example, it may be a polyolefin-based resin such as polyethylene resin or polypropylene resin. , preferably a polypropylene resin.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

Example 1

A 0.2 M water glass solution is added dropwise to a 1.0 M aqueous sulfuric acid solution in the reactor, followed by stirring. Then, 1.0 M calcium chloride dihydrate (CaCl ₂ ·2H ₂ O) was slowly added dropwise to perform an ion exchange reaction. After confirming that a white precipitate (acicular metal salt particles) is generated within several tens of seconds, an aqueous ammonia solution (NH ₄ OH, about 30% solution) as a base catalyst is slowly added dropwise so that the pH in the reactor becomes about 7.5, and the needle-shaped metal salt A needle-like metal-silica wet gel composite was prepared by inducing a gelation reaction on the particle surface. Meanwhile, the ion exchange reaction and the gelation reaction were performed at 80° C. and 1.0 bar for 1 hour.

Thereafter, it was washed with distilled water 4 times to remove impurities, the solvent was replaced with ethanol, and then dried under atmospheric pressure at a temperature of 150° C. for 2 hours to prepare needle-shaped metal-silica airgel composite particles.

After reacting by adding 2 parts by weight of 3-APS (3-aminopropyltriethoxysilane) to water (distilled water) with respect to 100 parts by weight of the prepared needle-shaped metal-silica airgel composite particles, the reaction temperature was about 50° C. The needle-shaped metal-silica airgel composite particles were added to react, and the functionalized agent-derived group was combined to obtain a functionalized needle-shaped metal-silica airgel composite particle.

Examples 2 to 7

In Example 1, except that only the conditions described in Table 1 were changed, functionalized needle-shaped metal-silica airgel composite particles were prepared by binding with a functionalizing agent-derived group in the same manner as in Example 1.

Example 8

A 0.3 M water glass solution was added dropwise to a 1.0 M sulfuric acid aqueous solution in the reactor, followed by stirring. Then, 1.0 M calcium chloride dihydrate (CaCl ₂ ·2H ₂ O) was slowly added dropwise to perform an ion exchange reaction. After confirming that a white precipitate (acicular metal salt particles) is generated within several tens of seconds, an aqueous ammonia solution (NH ₄ OH, about 30% solution) as a base catalyst is slowly added dropwise so that the pH in the reactor becomes about 7.5, and the needle-shaped metal salt A needle-like metal-silica wet gel composite was prepared by inducing a gelation reaction on the particle surface. Meanwhile, the ion exchange reaction and the gelation reaction were performed at 80° C. and 1.0 bar for 1 hour.

Thereafter, it was washed with distilled water 4 times to remove impurities, the solvent was replaced with ethanol, and then dried under atmospheric pressure at a temperature of 150° C. for 2 hours to prepare needle-shaped metal-silica airgel composite particles.

3-APS (3-aminopropyltriethoxysilane) was added to water (distilled water) in 2 parts by weight based on 100 parts by weight of the prepared needle-shaped metal-silica airgel composite particles to prepare a 3-APS dispersion.

Thereafter, the prepared needle-like metal-silica airgel composite particles are put into a high-speed stirrer, and the prepared 3-APS dispersion is added dropwise while stirring at high speed, stirred uniformly, and then dried and functionalized by binding the functionalizing agent-derived group. Acicular metal-silica airgel composite particles were obtained.

Examples 9 and 10

In Example 8, functionalized needle-shaped metal-silica airgel composite particles were prepared by binding a functionalizing agent-derived group in the same manner as in Example 8, except that only the conditions described in Table 1 were changed.

Comparative Examples 1 to 3

In Example 1, functionalized needle-shaped metal-silica airgel composite particles were prepared in the same manner as in Example 1, except that only the conditions described in Table 1 were changed without adding a functionalizing agent.

Experimental Example 1: Polymer resin blending properties

Based on the weight of polypropylene resin (PP resin, MI: 25g/10min), 10% by weight of needle-shaped metal-silica airgel composite particles of Examples and Comparative Examples were added and injection-extruded with an extruder (SM Twin Screw Extruder, Ø40) to have a needle-like shape. A PP resin specimen containing metal-silica airgel composite particles was prepared, and the following compounding properties were measured and described in Table 1 below.

1) Flexural strength measurement

The flexural strength of the PP resin specimens of Examples and Comparative Examples was measured using a method of supporting the specimen at two points and bending it by applying a load to the middle point (three-contact bending method). Specifically, the PP resin specimens of Examples and Comparative Examples were placed on two supports 2 inches apart, and a force was applied in the vertical direction to the center of the specimen at a predetermined speed to measure the force (flexural strength) at the breaking point.

2) Tensile strength measurement

The tensile strength of both ends of the PP resin specimens of Examples and Comparative Examples was measured according to the measurement method of ASTM D638 using an Instron tensile tester.

3) Impact strength measurement

The PP resin specimens of Examples and Comparative Examples were measured for impact strength according to the IZOD impact strength measurement method, and are shown in Table 1 below.

4) Dispersibility test (ASH test)

The PP resin specimens of Examples and Comparative Examples were put in a furnace at 700° C., and the weight of the ash remaining after heat treatment was performed for 240 minutes was measured, and the content ratio based on the weight of the polypropylene resin is shown in Table 1 below.

At this time, the closer the ASH content ratio to the content ratio (10% by weight) of the initially introduced needle-shaped metal-silica airgel composite particles, the better the dispersibility of the needle-shaped metal-silica airgel composite particles in the polypropylene resin.

concentration of reactant 3-APS input amount (parts by weight) flexural strength
(MPa) tensile strength
(MPa) impact strength
(J/m) ASH (wt%) Acid solution (M) Solution with metal salt (M)
water glass solution (M) Concentration ratio of water glass solution/acid solution Example 1 One One 0.2 0.2 2 30 20 48 7.8 Example 2 One One 0.3 0.3 2 32 21 50 7.5 Example 3 One One 0.4 0.4 2 34 21 53 7.6 Example 4 One One 0.5 0.5 2 36 22 55 7.4 Example 5 One One 0.6 0.6 2 37 23 60 7.5 Example 6 One One 0.7 0.7 2 39 23 59 7.3 Example 7 One One 0.8 0.8 2 39 23 60 7.7 Example 8 One One 0.3 0.3 2 27 18 45 7.3 Example 9 One One 0.5 0.5 2 29 18 45 7.2 Example 10 One One 0.8 0.8 2 30 19 49 7.4 Comparative Example 1 One One 0.2 0.2 - 27 17 44 7.1 Comparative Example 2 One One 0.4 0.4 - 28 18 44 6.6 Comparative Example 3 One One 0.6 0.6 - 25 17 41 6.9

As shown in Table 1, Examples 1 to 10 of the present invention have excellent flexural strength, tensile strength and impact strength of the polypropylene resin compared to Comparative Examples 1 to 3 in which no functionalizing agent is added, and the content ratio of ASH Since it is closer to the content ratio (10% by weight) of the needle-shaped metal-silica airgel composite particles that were initially introduced, it can be seen that the needle-shaped metal-silica airgel composite particles applied as an additive in the polypropylene resin are well dispersed. .

Specifically, when compared to Example 1 and Comparative Example 1 in which the concentration of the water glass solution is the same as the concentration of the acidic solution, it can be confirmed that the values of flexural strength, tensile strength and impact strength are all improved, and the ASH content ratio is also 10% by weight As it can be confirmed that it is closer to have.

In addition, Example 3 and Comparative Example 2, Example 5, and Comparative Example 3 also show similar differences for the same reason as in Example 1 and Comparative Example 1. In this case, as the concentration of the water glass solution increases compared to the concentration of the acidic solution, the difference It can be seen that the larger

In addition, when referring to Examples 1 to 10, a relatively high concentration of water glass solution was added to prepare needle-shaped metal-silica airgel composite particles, and reacted with a functionalizing agent when used as an additive to a polymer resin. It can be seen that the flexural strength, tensile strength and impact strength are further improved.

In addition, when referring to Examples 1 to 10, the particles of Examples 1 to 7 in which the functionalizing agent was dispersed in a solvent and reacted by adding needle-shaped metal-silica airgel composite particles to the dispersion were added to the polymer resin It can be seen that the mechanical strength can be further improved.

The above description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (15)

1) adding a water glass solution to the acidic solution in the reactor;
2) forming needle-shaped metal salt particles by dropwise adding a solution containing a metal salt after the addition of the water glass solution;
3) preparing a needle-shaped metal-silica wet gel complex by adding a basic catalyst to the solution in which the needle-shaped metal salt particles are precipitated and gelling;
4) drying the needle-shaped metal-silica wet gel composite to prepare needle-shaped metal-silica airgel composite particles; and
5) A method for producing a functionalized needle-shaped metal-silica airgel composite particle comprising the step of reacting the needle-shaped metal-silica airgel composite particle with a functionalizing agent.
According to claim 1,
The functionalizing agent is a method for producing a functionalized needle-shaped metal-silica airgel composite particles represented by the following formula (1).
[Formula 1]

In Formula 1,
R ¹ is a single bond or a substituted or unsubstituted divalent hydrocarbon group,
R ² and R ³ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms,
X is any one substituent selected from the group consisting of a vinyl group, an epoxy group, a glydoxy group, an amino group, a (meth)acryl group, (meth)acryloxy, a halogen group and a mercapto group,
a is an integer from 1 to 3.
According to claim 1,
The functionalizing agent is vinyl trimethoxysilane, vinyl tris(2-methoxyethoxy)silane, vinyl (3,4-epoxycyclohexyl)ethyltrimethoxysilane, glycidoxy propyl trimethoxysilane, glycidoxy Propyl methyldiethoxysilane, glycidoxy propyl triethoxysilane, methacryloxy propyl methyldimethoxysilane, methacryloxy propyl trimethoxysilane, methacryloxy propyl methyldiethoxysilane, N-(amino ethyl)-amino Propyl methyldimethoxysilane, N-(amino ethyl)-amino propyl trimethoxysilane, N-(amino ethyl)-amino propyl triethoxysilane, amino propyl trimethoxysilane, amino propyl triethoxysilane, N- A method for producing a functionalized needle-like metal-silica airgel composite particle comprising at least one selected from phenyl-amino propyl trimethoxysilane, chloro propyl trimethoxysilane and mercapto propyl trimethoxysilane.
According to claim 1,
The functionalizing agent is the needle-shaped metal-silica airgel composite particles functionalized by adding 0.1 to 5 parts by weight relative to 100 parts by weight of the needle-shaped metal-silica airgel composite particles.
According to claim 1,
The functionalizing agent is the needle-shaped metal-silica airgel composite particles functionalized by adding 0.5 to 3 parts by weight based on 100 parts by weight of the needle-shaped metal-silica airgel composite particles.
According to claim 1,
The concentration ratio of the acidic solution and the water glass solution is 1:0.1 to 1:0.8.
According to claim 1,
The concentration ratio of the acidic solution and the water glass solution is 1:0.6 to 1:0.8.
According to claim 1,
Step 5) is,
5-1) dispersing the functionalizing agent in a solvent; and
5-2) A method for producing a functionalized needle-shaped metal-silica airgel composite particle comprising the step of adding and reacting the needle-shaped metal-silica airgel composite particle to the dispersion in which the functionalizing agent is dispersed.
9. The method of claim 8,
The solvent is a method for producing a functionalized needle-shaped metal-silica airgel composite particles comprising water.
According to claim 1,
The concentration of the solution containing the acidic solution and the metal salt is each independently 0.5 M to 2.8 M of the functionalized needle-like metal-silica airgel composite particle production method.
According to claim 1,
The concentration ratio of the acidic solution and the solution containing the metal salt is 1:0.5 to 1:2 of the functionalized needle-shaped metal-silica airgel composite particle production method.
According to claim 1,
The solution containing the metal salt is a functionalized needle-shaped metal containing calcium (Ca) as a metal - a method for producing a silica airgel composite particles.
According to claim 1,
The acidic solution is a sulfuric acid (H ₂ SO ₄ ) aqueous solution of a functionalized needle-shaped metal-silica airgel composite particle production method.
According to claim 1,
The needle-shaped metal-silica airgel composite particles are functionalized needle-shaped metal-silica airgel composite particles in which silica airgel is bonded to the surface of the needle-shaped metal salt particles.
A functionalized needle-like metal-silica airgel composite particle prepared according to any one of claims 1 to 14,
Flexural strength of 27 MPa or more,
Tensile strength of 18 MPa or more,
A polymer resin with an impact strength of 45 J/m or more.

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