阅读说明：本技术 载有活性材料的气凝胶及水凝胶和气凝胶的复合物 (Aerogels loaded with active materials and hydrogel and aerogel composites ) 是由 金泰源 于 2019-01-21 设计创作，主要内容包括：提供一种载有活性材料的气凝胶,以及水凝胶和气凝胶的复合物。根据本发明的复合物的制备方法包括以下步骤：制备在孔中具有活性材料的多个气凝胶颗粒；制备将聚合物溶解在水溶性溶剂中的聚合物溶液；在将气凝胶颗粒混合到所述聚合物溶液中之后,通过均质化来制备气凝胶/聚合物分散体,并通过将所述分散体与交联剂溶液混合来制备气凝胶/水凝胶复合载体。根据本发明,通过制备其中分散有多个气凝胶颗粒的水凝胶复合物,可以提供其中可以同时载有油和水分而没有任何表面活性剂的复合载体。此外,可以制备具有改善的性质,例如低密度、高强度、高组分含量和稳定解吸的复合载体。(Aerogels loaded with active materials, and composites of hydrogels and aerogels are provided. The preparation method of the compound according to the invention comprises the following steps: preparing a plurality of aerogel particles having an active material in the pores; preparing a polymer solution in which a polymer is dissolved in a water-soluble solvent; after mixing the aerogel particles into the polymer solution, an aerogel/polymer dispersion is prepared by homogenization, and an aerogel/hydrogel composite carrier is prepared by mixing the dispersion with a crosslinker solution. According to the present invention, by preparing a hydrogel composite in which a plurality of aerogel particles are dispersed, it is possible to provide a composite carrier in which both oil and moisture can be carried without any surfactant. In addition, composite carriers having improved properties, such as low density, high strength, high component content, and stable desorption, can be prepared.)

1. A method of making an aerogel/hydrogel composite, comprising:

preparing a plurality of aerogel particles comprising aerogel particles having particle clusters and pores formed in a porous network of the particle clusters, and an active material supported in the pores;

preparing a polymer solution in which a polymer is dissolved in a water-soluble solvent;

mixing the plurality of aerogel particles into the polymer solution, and then homogenizing the mixture to produce an aerogel/polymer dispersion; and

the dispersion is mixed with a crosslinker solution to prepare an aerogel/hydrogel composite support.

2. The method of claim 1, wherein, in the step of preparing the plurality of aerogel particles, 1 to 10 parts by weight of the active material is mixed with 1 part by weight of the aerogel particles.

3. The method of claim 1, wherein the active material is a natural extract, a natural extract oil, an alcohol having 1 to 40 carbon atoms, an alkane, or an organic compound having an ester functional group having 4 to 40 carbon atoms.

4. The method of claim 1, wherein the polymer is dissolved in a water-soluble solvent and the cross-links are formed by the cross-linking agent in the cross-linking agent solution.

5. The method of claim 1, wherein 0.1 to 10 parts by weight of the gel particles are mixed with 10 parts by weight of the polymer solution.

6. The method according to claim 1, wherein, when preparing the aerogel/hydrogel composite carrier, the aerogel/polymer dispersion is dropped into the crosslinker solution to form the carrier having a spherical shape.

7. The method of claim 6, wherein the aerogel/hydrogel composite support comprises a hydrogel having a three-dimensional network structure formed by cross-linking the polymer and a plurality of aerogel particles dispersed in the network structure.

8. An aerogel/hydrogel composite, comprising:

a hydrogel having a three-dimensional network structure; and

a plurality of aerogel particles having aerogel particles comprising particle clusters and pores formed in a porous network of the particle clusters, and an active material supported in the pores.

9. The aerogel/hydrogel composite of claim 8, wherein the active material is a natural extract, a natural extract oil, an alcohol having 1 to 40 carbon atoms, an alkane, or an organic compound having an ester functional group having 4 to 40 carbon atoms.

10. The aerogel/hydrogel composite of claim 9, wherein the composite is a spherical support.

11. An aerogel comprising:

aerogel particles having particle clusters and pores formed in a porous network of the particle clusters; and

an active material supported in the pores.

12. The aerogel of claim 11, wherein the aerogel particles are hybrid aerogel particles.

13. The aerogel of claim 12, wherein the hybrid aerogel particles have, in addition to Si-O-Si groups, Si-CH groups on the infrared spectrum of the fourier transform₃Radicals and OH radicals.

Technical Field

The present invention relates to an aerogel, and more particularly, to an aerogel loaded with an active material and a composite of the hydrogel and the aerogel.

Background

Aerogels were first developed in 1931 and were formed by replacing the liquid portion of the gel with gas. It is an ultra-light porous material known to be made of metal oxides, such as silica, alumina, titania, zirconia, iron oxide; carbon; or agar. Aerogels can be used in a variety of fields, such as construction, industry, cosmetics, and biochemistry.

These aerogels have characteristics of heat insulation, sound insulation, and electromagnetic wave shielding due to their high microporosity, and thus can be used in various industrial fields such as buildings, building thermal insulation materials, and sound insulation materials (US6,136,216 and US 2010/0275617).

Disclosure of Invention

Technical problem

The problem to be solved by the present invention is to provide a composite carrier capable of supporting oil and moisture without using a surfactant, and a method for manufacturing the same. In addition, the present invention provides a composite carrier having improved properties such as low density, high strength, high component content and stable desorption.

Another problem to be solved by the present invention is to provide an aerogel composite capable of further improving the performance of an active material having a function such as fragrance diffusion.

Technical scheme

One aspect of the present disclosure provides a method of making an aerogel composite. The method of making an aerogel composite comprises: preparing a plurality of aerogel particles having aerogel particles comprising particle clusters and pores formed by a porous network of the particle clusters, and an active material supported in the pores; preparing a polymer solution in which a polymer is dissolved in a water-soluble solvent; mixing the plurality of aerogel particles into the polymer solution, and then homogenizing the mixture to produce an aerogel/polymer dispersion; the dispersion is mixed with a crosslinker solution to prepare an aerogel/hydrogel composite support.

In the step of preparing the plurality of aerogel particles, 1 to 10 parts by weight of the active material may be mixed with 1 part by weight of the aerogel particles. The active material may be a natural extract, a natural extract oil, an alcohol having 1 to 40 carbon atoms, an alkane, or an organic compound having an ester functional group having 4 to 40 carbon atoms.

The polymer may be dissolved in the water-soluble solvent and cross-links are formed by the cross-linking agent in the cross-linking agent solution. 0.1 to 10 parts by weight of the aerogel particles may be mixed with 10 parts by weight of the polymer solution. When the aerogel/hydrogel composite carrier is prepared, the aerogel/polymer dispersion may be dropped into the crosslinker solution to form the spherical carrier. The aerogel/hydrogel composite support comprises a hydrogel having a three-dimensional network structure formed by cross-linking the polymer and a plurality of aerogel particles dispersed in the network structure.

Another aspect of the invention provides an aerogel composite. The aerogel composite includes a hydrogel having a three-dimensional network structure, and a plurality of aerogel particles having aerogel particles comprising particle clusters and pores formed in a porous network of the particle clusters, and an active material supported in the pores.

The active material may be a natural extract, a natural extract oil, an alcohol having 1 to 40 carbon atoms, an alkane, or an organic compound having an ester functional group having 4 to 40 carbon atoms. The complex may be a spherical support.

Another aspect of the invention provides an aerogel. The aerogel comprises: aerogel particles having particle clusters and pores formed in a porous network of the particle clusters; and an active material supported on the aperture. The aerogel particles can be hybrid aerogel particles. The mixed aerogel particles exhibit Si-O-Si groups, Si-CH groups on Fourier transform infrared spectroscopy₃Groups and OH groups.

Advantageous effects

As described above, according to the present invention, by manufacturing a hydrogel composite in which a plurality of aerogel particles are dispersed in a hydrogel, a composite carrier that can support oil and moisture without a surfactant can be provided. In addition, a composite carrier having improved properties such as low density, high strength, high component content, and stable desorption can be provided.

In accordance with the present invention, there is provided an aerogel composite comprising an aerogel having both hydrophobic and hydrophilic properties and an active material supported therein to improve the functionality of the active material, particularly the fragrance diffusion properties.

Advantageous effects of embodiments of the present invention are not limited to the above-described advantageous effects, and other advantageous effects of the present invention may be clearly understood from the following description.

Drawings

Fig. 1 is a schematic view (a) schematically showing an aerogel of a first embodiment of the present invention, and a schematic view (b) showing (a) in an enlarged scale.

Fig. 2 is a flow chart sequentially illustrating a method of manufacturing an aerogel/hydrogel composite according to a second embodiment of the present invention.

Fig. 3 is a schematic diagram of step S30 of the method of fig. 2.

Fig. 4(a) is a sectional view showing a section of an aerogel/hydrogel composite particle according to a first embodiment of the present invention, and fig. 4(b) is an enlarged view of fig. 4 (a).

Fig. 5a to 5c are graphs respectively showing the results of measurement of the powders obtained in aerogel surface modification examples 1 to 3 by Fourier-transform infrared spectroscopy (FT-IR spectroscopy).

Fig. 6 is a photograph of an aerogel/hydrogel composite carrier according to preparation example 2.

Fig. 7 is a graph showing the daily evaporation amount (g) in the results of experimental example 1.

Fig. 8 is a graph showing the cumulative evaporation amount (g) in the results of experimental example 1.

Fig. 9 is a graph showing the evaporation rate (%) in the results of experimental example 1.

Fig. 10 is a graph showing the daily evaporation amount (g) in the results of experimental example 2.

Fig. 11 is a graph showing the cumulative evaporation amount (g) in the results of experimental example 2.

Fig. 12 is a graph showing the evaporation rate (%) in the results of experimental example 2.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. However, it is not intended to limit the invention to the particular forms disclosed, but, to the invention, the invention includes all modifications, equivalents, and alternatives falling within the spirit of the invention as defined by the claims.

Aerogels loaded with active materialsPreparation of

Fig. 1 is a schematic view (a) schematically showing an aerogel of a first embodiment of the present invention, and a schematic view (b) showing (a) in an enlarged scale.

Referring to fig. 1(a), the aerogel of the present invention has a plurality of aerogel particles (10), and the aerogel particles (10) may have a structure in which a plurality of nano-sized pores are dispersed and an active material (13) is supported in the pores.

Specifically, referring to fig. 1(b), aerogel particles (10) can comprise a porous network of particle clusters (11) and pores (12) in the network. The aerogel particles (10) can be formed by aggregation of the particle clusters (11), and the overall shape thereof can be irregular. Here, the diameter of the aerogel particles (10) may be the diameter of an outer sphere (circumscript sphere), and the diameter may be micrometer-sized. For example, the aerogel particles (10) can have a diameter of 0.1 to 1000 μm, in particular a few μm to a few tens of μm, for example 1 to 40 μm.

The surface area of the aerogel particles (10) by the BET method can be 300 to 2000m²A/g, in particular from 500 to 1000m²(iv)/g, which may have a density of 0.03 to 0.5g/cc, a porosity of 70 to 99%, and a pore diameter of 5 to 50 nm. For example, the aerogel particles (10) can be silica aerogel particles.

The aerogel particles (10) can be hydrophobic aerogel particles having a hydrophobic surface, hydrophilic aerogel particles having a hydrophilic surface, or hybrid aerogel particles having both a hydrophobic surface and a hydrophilic surface. Hydrophobic aerogel particles can have a hydrophobic surface in the pores within the particle in addition to the outer surface of the particle, and hydrophilic aerogel particles can have a hydrophilic surface in the pores within the particle in addition to the outer surface of the particle. In addition to this, the hybrid aerogel particles can have hydrophobic and hydrophilic surfaces in the pores inside the particles as well as in the outer surface of the particles.

In one embodiment, the aerogel particles (10) can be a mixture comprising hydrophilic aerogel particles, hydrophobic aerogel particles, and mixed aerogel particles. In the mixture, about 25 to 40 wt% of mixed aerogel particles can be contained, about 25 to 40 wt% of hydrophilic aerogel particles can be contained, and about 25 to 40 wt% of hydrophobic aerogel particles can be contained. In one embodiment, the ratio of 1: 1: 1 comprises mixed aerogel particles, hydrophilic aerogel particles, and hydrophobic aerogel particles.

The hydrophobic aerogel particles can have predominantly hydrophobic functional groups, such as hydrogen, C1-C18 linear or branched alkyl groups, silyloxy groups, or combinations thereof. The hydrophilic aerogel particles can have predominantly hydrophilic functional groups, such as hydroxyl (-OH) groups, on their surfaces. The mixed aerogel particles can have hydrophobic functional groups and hydrophilic functional groups on their surfaces.

Specifically, the mixed aerogel particles may be those in which a hydrophilic functional group and a hydrophobic functional group (R) are bonded to Si atoms as components of the aerogel particles. The hydrophilic functional group may be a hydroxyl group (-OH). The hydrophobic functional group (R) may be hydrogen, a C1-C18 linear or branched alkyl group, a siloxy group represented by the following chemical formula 1, or a combination thereof.

[ chemical formula 1]

*-OSiH_(3-n)R¹ _n

In chemical formula 1

R¹Is C1-C18 straight chain or branched chain alkyl,

n is an integer between 0 and 3,

denotes bonds to Si in the aerogel particles.

When n is an integer of 1 to 3, the functional group represented by chemical formula 1 may be referred to as an alkylsiloxy group. The C1-C18 linear or branched alkyl group can be a C1-C6 linear alkyl group, or the C1-C6 linear alkyl group can be a saturated linear alkyl group, such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, or n-hexyl. For example, the C1-C6 linear alkyl groups can be methyl or ethyl groups. In one embodiment, the mixed aerogel particles can have a particle size distribution on their surface of 7: 3 to 3: 7 has a hydrophobic functional group (R) and a hydrophilic functional group (OH).

The active material (13) may be absorbed in the aerogel particles (10), and in particular, may be supported in the pores (12) of the aerogel particles (10) to exhibit functionality, and may be a liquid material at room temperature. Here, the functionality of the active material (13) may refer to, for example, fragrance supply, nutrition supply, skin protection, treatment, medicine, etc., but is not limited thereto, and the active material (13) may be a hydrophobic active material or a hydrophilic active material, but is not limited thereto if having the above-described function.

The active material may be a natural extract or natural extract oil, such as alfalfa extract, algae extract, almond oil, arnica oil, borage oil, or mineral oil.

The active material may be an alcohol having 1 to 40 carbon atoms, such as methanol, ethanol, propanol, isopropanol, ethylene glycol, butylene glycol, glycerol; alkanes having 4 to 40 carbon atoms, such as isodecane, isohexadecane, liquid paraffin, hydrogenated polyisobutene, polyalkylene oxides, in particular polyethylene glycol; or organic compounds having an ester functional group, such as isopropyl myristate, alkyl benzoate, capric triglyceride, isopropyl palmitate, polymethyl methacrylate.

The active material may be a fragrance oil, such as cottonseed oil, lavender essential oil, vanilla oil, cinnamon oil, citronella oil, medlar fragrance oil, orange oil, tangerine oil, apple seed oil, caraway oil, cedar oil, sandalwood oil, juniper oil, nutmeg oil, anise oil, patchouli oil, rose oil, clove oil, saffron oil, lavender oil, rosemary oil, sage essential oil, lemon oil, peppermint oil, sweet basil oil, bergamot oil, camellia oil (or tea seed oil), chamomile oil, catmint oil, bay leaf oil, citrus oil, coffee essential oil, coconut oil, oregano oil, ylang oil, orange flower essential oil, bergamot essential oil, rose petal oil, jasmine essential oil, vetiver essential oil, citrus essential oil, olive essential oil, orange leaf oil, sweet orange oil, myrrh essential oil, canola oil, or milk sesame oil.

For example, the active material (13) may be a hydrophobic active material, in particular an oil, more particularly an oil capable of evaporating aromatic components, i.e. a fragrant oil.

For example, the aerogels of the present invention may be used as fragrance products themselves. Aerogels can further improve flavor characteristics, such as flavor performance and flavor longevity, compared to previously used fragrance oils.

For example, the aerogel of the present invention is a mixed aerogel comprising mixed aerogel particles (10) having both hydrophobicity and hydrophilicity and an active material (13) carried or supported by the mixed aerogel particles (10). The active material (13) may be a hydrophobic active material, in particular an oil, more particularly an oil capable of evaporating (evaporate) fragrance components, i.e. an oil whose fragrance is smelled. The hybrid aerogel has both hydrophobic and hydrophilic characteristics, and thus the evaporation rate (evaporation rate) can be adjusted and the fragrance durability can be improved, compared to the case of using the fragrant oil alone. In addition, the flavor property and flavor duration can be further improved as compared with the case of using the hydrophobic aerogel. In addition, by controlling the amount and fraction (fraction) of the mixed aerogel particles and fragrance oil in the mixed aerogel composite, the fragrance performance and fragrance longevity can be further improved.

The active material loaded aerogel composites of the present invention can be made by preparing aerogel particles and mixing the aerogel particles with the active material.

The method of making the hybrid aerogel particles can be as follows. However, it is not limited thereto. First, a hydrophobic aerogel powder having hydrophobic aerogel particles can be prepared. Hydrophobic aerogel powders can be prepared by modifying the surface of a hydrogel to be hydrophobic, followed by drying and milling.

The hydrophobic aerogel powder can be heat treated to partially modify the surface of the outer surface of the particles in the powder as well as the surface of the inner pores of the particles. In particular, the hydrophobic surface functional groups of at least some of the particles provided in the hydrophobic aerogel powder can be changed to hydrophilic surface functional groups. Specifically, hydrophobic surface functional groups such as hydrogen, alkyl groups or siloxy groups, in particular siloxy groups, can be converted into hydroxyl groups by thermal treatment. At the same time, residual moisture in the aerogel powder can be at least partially or completely removed.

The heat treatment of the hydrophobic aerogel powder may include a temperature-raising step of gradually raising the temperature of the hydrophobic aerogel powder, and a sintering step of maintaining the hydrophobic aerogel powder in a heated state for a predetermined time to sinter the hydrophobic aerogel powder.

Thus, as described above, at least some of the particles of the hydrophobic aerogel powder can be converted into hybrid aerogel particles having a hydrophobic surface and a hydrophilic surface, and some other particles can be converted into hydrophilic aerogel particles having a hydrophilic surface, while some other particles can remain as hydrophobic aerogel particles that retain a hydrophobic surface. As a result, an aerogel powder comprising a mixture of all hydrophilic aerogel particles, hydrophobic aerogel particles, and mixed aerogel particles can be obtained.

When the hydrophobic aerogel includes alkyl groups (CH)₃) When compared to hydrophilic aerogels, hydrophobic aerogels have larger particle sizes, smaller pore volumes, and smaller pore surface areas. As the alkyl group is oxidized to form a hydroxyl group, the size of the aerogel particles decreases as the size of the functional group decreases, and the pore volume and the surface area of the pores increase. Therefore, the hydrophilicity can be increased by increasing the space capable of absorbing moisture.

The heat treatment may be performed using an electric furnace, and may be performed in a state where the temperature is increased to 300 to 500 ℃ for 0.5 to 24 hours. In addition, the heat treatment may be performed in an oxidizing atmosphere, particularly an air atmosphere. For example, only some of the hydrophobic surface functional groups of the hydrophobic aerogel can be changed to hydrophilic surface functional groups by heat treatment at about 345 to 355 ℃, particularly 347 to 353 ℃. Hydrophilic aerogels in which all the hydrophobic surface functional groups of the hydrophobic aerogel have been changed to hydrophilic surface functional groups can be formed by heat treatment at about 356 to 365 ℃, particularly 357 to 363 ℃.

The aerogel composite can be prepared by physically mixing, e.g., mixing the aerogel particles (10) and the active material (13) in a bowl or the like. For example, 1 to 10 parts by weight, specifically 2 to 9 parts by weight, more specifically 3 to 8 parts by weight, more specifically 4 to 7 parts by weight of the active material (13) can be mixed with 1 part by weight of the aerogel. When the aerogel particles (10) have both hydrophilicity and hydrophobicity, the aerogel particles (10) can be easily mixed with each of the hydrophobic active material or the hydrophilic active material. An active material (13), such as a hydrophobic active material, specifically an oil, more specifically a scented oil, may be supported in the pores (12) of the aerogel particles (10).

Preparation of aerogel/hydrogel composites

Fig. 2 is a flowchart sequentially illustrating a method of manufacturing an aerogel/hydrogel composite according to a second embodiment of the present invention, and fig. 3 is a schematic view of step S30 of the method of fig. 2.

Referring to fig. 2 and 3, aerogel particles loaded with an active material may be prepared according to the above-described embodiment described with reference to fig. 1 (S10). A polymer (S11) may be provided. The polymer may be a hydrophilic polymer, and in particular, the polymer may be prepared as a polymer solution in which the polymer is dissolved in a water-soluble solvent such as water.

A polymer may be used as long as it can be dissolved in a water-soluble solvent, and a cross-link can be formed between chains of the polymer by a cross-linking agent. For example, the polymer may be a natural hydrophilic polymer such as pectin, gelatin, cellulose (especially carboxymethyl cellulose (CMC)), collagen, dextran, elastin, chitin, chitosan, sodium alginate; or synthetic hydrophilic polymers such as polyacrylic acid (PAA), polyvinyl alcohol, polyethylene glycol, polyvinylpyrrolidone, polyurethane, polyhydroxyethylmethacrylate, silicone; or any combination thereof. For example, the polymer may be sodium alginate.

An aerogel/polymer dispersion (21) can be prepared in which aerogel particles are mixed in a polymer solution, specifically, a plurality of aerogel particles are loaded with an active material (S20). The mixing may be, for example, stirring using a high-speed mixer or a ball mill to uniformly disperse the aerogel particles in the polymer solution. Therefore, a plurality of aerogel particles can be uniformly mixed without being coagulated in the hydrophilic polymer solution.

For example, the aerogel particles can be mixed in an amount of 0.1 to 10 weight, specifically 0.1 to 5 weight, and more specifically 0.1 to 1 weight, based on 10 weight of the aqueous polymer solution. The stirring speed may be 10rpm to 200rpm, specifically, 50rpm to 150rpm, more specifically, 80rpm to 100 rpm.

The aerogel/polymer dispersion (21) may be mixed with the crosslinker solution (22) to form the aerogel/hydrogel composite carrier (100) (S30). The crosslinking agent solution (22) may be a solution in which the crosslinking agent is dissolved in a solvent, particularly a water-soluble solvent such as water.

The crosslinking agent may form three-dimensional crosslinks (represented by C in fig. 3) by chemically bonding with the polymer. The crosslinking agent may be, for example, calcium chloride, calcium sulfate, calcium nitrate, zinc chloride, zinc sulfate, ammonium persulfate, or glutaraldehyde. The crosslinking agent is not limited thereto, and may vary depending on the type of the polymer. The polymer can be converted into a hydrogel by such a crosslinking agent.

For example, cross-linking of the polymer may be formed by ionic bonding of calcium ions in the cross-linking agent. For example, the crosslinker solution (22) may be an aqueous solution of calcium chloride. For example, in the crosslinking agent solution (22), the crosslinking agent may be mixed in a weight of 0.01 to 0.1 based on 10 weight of the solvent.

Mixing can be carried out by dropping the aerogel/polymer dispersion (21) into the crosslinker solution (22). Specifically, the dispersion (21) may be set in a storage device (40) such as a pipette, and may be dropped at a constant size and dropped at a constant speed into the crosslinking agent solution (22) through a nozzle (41). Thus, the aerogel/polymer dispersion (21) can be cured by reacting with the crosslinker solution (22) to form a spherical support, i.e., the aerogel/hydrogel composite support 100. For example, the aerogel/hydrogel composite support 100 can have an average diameter of 100 μm to 10 mm.

Fig. 4(a) is a sectional view illustrating a section of an aerogel/hydrogel composite particle according to an embodiment of the present invention. Fig. 4(b) is an enlarged view of fig. 4 (a).

Referring to fig. 4(a) and 4(b), the aerogel/hydrogel composite (100) of the present invention comprises a hydrogel (20) having a three-dimensional network structure and a plurality of aerogel particles dispersed in the network (10). The aerogel particles (10) can contain active materials (13) in their pores (12).

Specifically, as described above with reference to fig. 3, when the aerogel/polymer dispersion (21 in fig. 3) is dropped dropwise into the crosslinker solution (22 in fig. 3), the polymer in the aerogel/polymer dispersion (21 in fig. 3) can be crosslinked by the crosslinker. For example, the carboxyl group contained in sodium alginate as an example of the polymer may form an ionic bond with a calcium ion of a crosslinking agent such as calcium chloride. Thus, from the surface of the dispersion droplets to the inside direction, the polymer may be gradually crosslinked, i.e., gelled to form a hydrogel having a three-dimensional network structure, thereby forming a support having an approximately spherical shape. At this time, the plurality of aerogel particles (10) uniformly dispersed in the dispersion (21) can be uniformly distributed in the network structure of the hydrogel (20).

In other words, the aerogel/hydrogel composite (100), i.e., the aerogel/hydrogel composite support 100, of the present invention can have a plurality of aerogel particles (10) within a network structure of the hydrophilic hydrogel (20), the aerogel particles (10) cannot aggregate with each other, and can be uniformly dispersed in the hydrogel (20). Specifically, the plurality of aerogel particles can be uniformly dispersed in the polymer solution by the above-mentioned high-speed stirring, and the plurality of aerogel particles can be maintained in a uniformly dispersed state in the network structure of the hydrogel (20) formed by crosslinking by the crosslinking agent, particularly crosslinking by calcium ions (C) in the crosslinking agent, without being aggregated with each other.

Thus, the aerogel/hydrogel composite carrier (100) can absorb or contain a large amount of moisture through the hydrogel (20), and can include an active material (13), particularly a hydrophobic active material exhibiting functionality, absorbed and contained in the pores (12) of the aerogel (10). Therefore, the active material (13) can be uniformly dispersed in the network structure of the hydrogel (20).

In addition, the stability of the network structure of the hydrogel (20) in the composite carrier (100) can compensate for the low mechanical properties of the aerogel particles (10), and can stably contain both water and oil in the aerogel/hydrogel composite carrier. Thus, a composite carrier (100) may be provided having improved properties, such as low density, high strength, high component content and stable desorption.

The composite carrier (100) may be applied to various fields such as food, cosmetics, biochemistry and medicine, and may be used as, for example, a diffuser (diffuser), perfume, cosmetics and nutraceuticals.

Hereinafter, preferred embodiments are provided to aid understanding of the present invention. However, the following experimental examples are only for helping understanding of the present invention, and the present invention is not limited by the following experimental examples.

< preparation of aerogel carrying active Material >

Preparation example 1: preparation of aerogels loaded with active Material (Mixed aerogel particles)

Having a trimethylsiloxy (-OSi (CH) group on the surface₃)₃) The hydrophobic aerogel of (a) was placed in an electric furnace in an oxidizing atmosphere, heated to 345 ℃, and then sintered for 1 hour in a state where the temperature was maintained, thereby preparing a mixed aerogel. 0.5g of the prepared aerogel blend and 4.375g of essential oil (peach essential oil) were mixed in a bowl.

Preparation example 2: preparation of aerogels loaded with active Material (hydrophobic aerogel particles)

An active material-loaded aerogel was prepared in the same manner as in preparation example 1, except that 1.0g of hydrophobic aerogel was mixed instead of the mixed aerogel and 3.5g of essential oil.

< preparation example of aerogel/hydrogel composite >

A clear aqueous sodium alginate solution was prepared by mixing 5g of sodium alginate with 95g of water at 80 ℃ for 3 hours using an electronic stirrer. Aerogel particles were prepared by mixing 1g of crushed silica aerogel powder in a bowl with 3g of lavender oil. The aqueous sodium alginate solution and aerogel particles were mixed using a ball mill for 3 hours to prepare an aerogel/sodium alginate dispersion. Meanwhile, a transparent calcium chloride aqueous solution was prepared by mixing 5g of calcium chloride and 200g of water using an electronic stirrer. Thereafter, the aerogel/sodium alginate dispersion was dropped into the aqueous calcium chloride solution by a pipette. When the aerogel/sodium alginate dispersion is dropped into the calcium chloride solution, it solidifies to produce an aerogel/hydrogel composite carrier having a perfume function.

< example 1 for modifying aerogel surface >

Having a trimethylsiloxy (-OSi (CH) group on the surface₃)₃) The hydrophobic aerogel powder of (a) was placed in an electric furnace in an oxidizing atmosphere, heated to 340 ℃, and sintered for 1 hour while maintaining the temperature.

< example 2 for modifying aerogel surface >

Hydrophobic aerogel powder was sintered in the same manner as in aerogel surface modification example 1, except that it was sintered at 350 ℃.

< example 3 for modifying aerogel surface >

Hydrophobic aerogel powder was sintered in the same manner as in aerogel surface modification example 1, except that it was sintered at 360 ℃.

Fig. 5a to 5C are graphs showing the results of fourier transform infrared spectroscopy (FT-IR spectroscopy) measurement of the powders obtained in aerogel surface modification examples 1 to 3, respectively.

Referring to FIG. 5a, it can be seen that the aerogel according to aerogel surface modification example 1 shows Si-CH in addition to Si-O-Si groups inherent to silica (silica)₃Groups, which indicates that the aerogel remains as a hydrophobic aerogel having a hydrophobic surface even after heat treatment.

Referring to FIG. 5b, it can be seen that the aerogel according to aerogel surface modification example 2 showed Si-CH in addition to Si-O-Si groups inherent to silica₃Groups and OH groups, indicating that the aerogel is a mixed aerogel formed by partially modifying a hydrophobic surface to a hydrophilic surface by heat treatment.

Referring to FIG. 5c, it can be seen that the aerogel according to aerogel surface modification example 3 showed OH groups in addition to Si-O-Si groups inherent to silica, and the observed corresponding to Si-CH before surface modification₃The peak of the group completely disappeared, indicating that the aerogel had converted into a hydrophilic aerogel formed by completely modifying the hydrophobic surface into a hydrophilic surface by heat treatment.

Fig. 6 is a photograph of an aerogel/hydrogel composite carrier prepared according to an aerogel/hydrogel composite preparation example of the present invention.

Referring to fig. 6, it can be confirmed that the aerogel/hydrogel composite carrier having a spherical shape is prepared.

Experimental example: analysis of aroma characteristics

Experimental example 1: flavor Property analysis (1) -preparation example 1 and comparative example

The aerogel of preparation example 1 was left at room temperature (25 ℃), and the fragrance (evaporation) performance with respect to the elapsed time (21 days) was measured during this process, specifically, the daily evaporation amount (g), the cumulative evaporation amount (g), and the evaporation rate (%). For accurate comparison, the flavor characteristics of pure essential oil (4.375 g) without aerogel complex (comparative example) were compared. In addition, in order to reduce errors, sample 1 and sample 2 were prepared according to preparation example 1, and then their average values were calculated. Samples 1 and 2 (oils with mixed A/G) were prepared by mixing 0.5G of mixed aerogel with 4.375G of essential oil as described above.

Tables 1 to 3 show the results of the daily evaporation amount (g), the cumulative evaporation amount (g) and the evaporation rate (%) in experimental example 1, respectively. Fig. 7 to 9 are graphs showing the daily evaporation amount (g), the cumulative evaporation amount (g), and the evaporation rate (%), respectively. (daily evaporation amount (g) (FIG. 7), cumulative evaporation amount (g) (FIG. 8), and evaporation Rate (%) (FIG. 9))

[ Table 1]

Table 1: daily evaporation amount (g) -preparation example 1 and comparative example

Referring to tables 1 and 7, in the case of the pure oil as the comparative example, it was confirmed that the initial evaporation amount per day (day 1 to day 4) was larger than that of preparation example 1, but the daily evaporation amount was significantly reduced after 10 days, and almost no evaporation was observed after 21 days. On the other hand, in the case of the mixed aerogel of preparation example 1, it was confirmed that the daily evaporation amount remained almost unchanged even after 20 days, and fragrance emission continued even after 21 days.

[ Table 2]

Table 2: cumulative amount of Evaporation (g) -production example 1 and comparative example

Referring to table 2 and fig. 8, in the case of the pure oil as the comparative example, since the daily evaporation amount was significantly reduced after 10 days, the cumulative evaporation amount became saturated after 17 days, whereas in the case of the mixed aerogel of preparation example 1, it was confirmed that the cumulative evaporation amount was stably increased even after 21 days had elapsed. As a result, it can be seen that the mixed aerogel of the present invention has an excellent effect of maintaining fragrance as compared to the essential oil itself.

[ Table 3]

Table 3: evaporation Rate (%) -production example 1 and comparative example

Referring to table 3 and fig. 9, in the case of the pure oil of the comparative example, the evaporation rate was not increased any more after 17 days, whereas in the case of the mixed aerogel of preparation example 1, the evaporation rate was stably increased even after 21 days. As a result, it can be seen that the mixed aerogel of the present invention has excellent flavor properties as well as excellent constant flavor, compared to the existing essential oils.

Experimental example 2: analysis of flavor Properties (2) -preparation examples 1 and 2

The aerogel composites according to preparation examples 1 and 2 were analyzed for fragrance characteristics in the same manner as in experimental example 1, except for the following.

A mixed aerogel complex of preparation example 1 was prepared using 1.0g of mixed aerogel and 3.5g of essential oil, the contents of which were different from those of the above preparation example 1. As a comparative example, 3.5g of pure essential oil was used. The elapsed time for the fragrance was 7 days.

Tables 4 to 6 show the results of experimental example 2, daily evaporation (g), cumulative evaporation (g) and evaporation rate (%), respectively. Fig. 10 to 12 are graphs showing the daily evaporation amount (g), the cumulative evaporation amount (g), and the evaporation rate (%), respectively. (daily evaporation amount (g) (FIG. 10), cumulative evaporation amount (g) (FIG. 11), and evaporation Rate (%) (FIG. 12))

[ Table 4]

Table 4: daily Evaporation amount (g) preparation 1, preparation 2 and comparative example

Referring to table 4 and fig. 10, in the case of the pure oil of the comparative example and the hydrophobic aerogel composite of preparation example 2, it can be confirmed that the initial evaporation amount (about 2 days) was higher than that of the mixed aerogel composite of preparation example 1. In particular, the comparative example showed the highest initial evaporation amount, and it is considered that the evaporation of the pure oil occurred without being interfered by the aerogel particles.

However, it can be seen that the evaporation amount was much reduced in comparative example and production example 2 from day 3 to day 4 as compared with production example 1. In particular, in the case of the hydrophobic aerogel of preparation example 2, the daily evaporation amount was the lowest after the fourth day, and therefore, it was confirmed that the hydrophobic aerogel had poor fragrance durability.

On the other hand, in the case of the mixed aerogel composite of preparation example 1, the initial evaporation amount was smaller than those of comparative example and preparation example 2, but it was found that the evaporation amount did not significantly decrease even after a period of time and remained at the highest evaporation amount after 4 days.

[ Table 5]

Table 5: cumulative amount of Evaporation (g) preparation 1, preparation 2 and comparative example

Referring to table 5 and fig. 11, for the hydrophobic aerogel of preparation example 2, as shown in fig. 10, since the evaporation amount was significantly reduced by day 4, the cumulative evaporation amount was hardly increased by day 4. When the pure oil of comparative example and the mixed aerogel of production example 1 were compared, it was determined that the increase rate of the cumulative evaporation amount of production example 1 was larger as time passed. That is, production example 1 showed that the daily evaporation amount was kept more constant than that of the comparative example. Thus, the hybrid aerogel according to the present invention shows that the evaporation amount can be controlled by adjusting the content and fraction of oil and aerogel powder.

[ Table 6]

Table 6: evaporation Rate (%) -production example 1, production example 2, and comparative example

Referring to table 6 and fig. 12, in the case of preparation example 2 using the hydrophobic aerogel, the evaporation rate was not increased any more due to rapid decrease in the amount of daily evaporation, and thus the fragrance performance was not good.

In the case of the comparative example, although the change in the evaporation rate was almost constant over the course of 6 days, it was understood that since the evaporation rate was higher than that in preparation example 1, the supported oil was rapidly consumed.

On the other hand, in the case of preparation example 1, it was confirmed that the change in the evaporation rate was kept constant over the lapse of 6 days, and therefore, it was confirmed that the cumulative evaporation amount and the evaporation rate steadily increased. That is, preparation example 1 of the present invention shows that fragrance can be maintained for a long time and excellent fragrance performance can be consistently exhibited for a long time, as compared to comparative examples.

Thus, in the case of preparation example 1, it can be seen that the evaporation amount and evaporation rate can be controlled according to the respective amounts and fractions of the mixed aerogel and oil, and thus the flavor property and flavor duration can be optimized.

The present invention has been described in detail above with reference to the preferred embodiments, but the present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and changes within the spirit and scope of the present invention.