CN115466518A - Organic-inorganic in-situ hybrid aerogel heat-insulating material and preparation method thereof - Google Patents
Organic-inorganic in-situ hybrid aerogel heat-insulating material and preparation method thereof Download PDFInfo
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Abstract
The invention discloses an organic-inorganic in-situ hybrid aerogel thermal insulation material and a preparation method thereof, and relates to the technical field of thermal insulation materials. The preparation method of the organic-inorganic in-situ hybrid aerogel heat-insulating material comprises the following steps: preparing sol; (2) gelling; and (3) drying to prepare the aerogel. The method disclosed by the invention is simple in process, short in production period and free of an acid-base catalyst, and the obtained organic-inorganic in-situ hybrid aerogel heat-insulating material has high strength, excellent compression resilience, heat-insulating property and good temperature resistance, and has a wide application prospect in the field of heat insulation.
Description
Technical Field
The invention relates to the technical field of heat insulation materials, in particular to an organic-inorganic in-situ hybrid aerogel heat insulation material and a preparation method thereof.
Background
Aerogel is the solid material with the lowest density currently known in the world, and has a typical three-dimensional nano porous network structure, so that the unique structure endows the aerogel with the characteristics of low density, high specific surface area, large porosity and the like, and therefore, the aerogel shows excellent performances in the aspects of adsorption, filtration, catalysis, heat insulation, noise reduction and the like. Aerogel materials are various in types, and different types of aerogels, such as inorganic oxide aerogel, polymer aerogel, biomass aerogel, carbon aerogel, carbide aerogel, semiconductor aerogel, metal aerogel and the like, can be prepared by adopting different precursors. Wherein, siO 2 The aerogel is a novel super heat-insulating material which is earliest in research and most potential in application, the normal-temperature heat conductivity of the aerogel can be as low as 0.012W/(m.K), and the aerogel has great application potential in the aspects of heat protection of weapons and equipment, heat pipelines of petrochemical industry, heat management of new energy automobile batteries, logistics transportation, heat preservation and heat insulation in the construction industry and the like.
SiO 2 The precursor of the aerogel is prepared by adopting organic silicon sources such as ethyl orthosilicate, methyl orthosilicate and the like or inorganic silicon sources such as sodium silicate, water glass and the like, forming a pearl chain-shaped nanometer skeleton structure formed by stacking secondary particles formed by chemical bonds formed by condensation polymerization of van der Waals force and hydroxyl among particles through a sol-gel reaction, and removing a solvent among the skeletons through a drying process to obtain the low-density SiO 2 An aerogel. Because the contact area between the secondary nano particles is small and the secondary nano particles are mostly rigidly connected by Si-O-Si bonds, siO is caused 2 The nano-skeleton structure of the aerogel has low strength, macroscopically shows large brittleness and poor toughness, is easy to fall powder and slag, and greatly limits SiO 2 And (5) practical application of the aerogel. The invention patent with the patent publication number of CN104402395A discloses a fiber-reinforced flexible SiO 2 The aerogel heat-insulating material and the preparation method thereof adopt the fiber felt pad as the reinforcement to prepare the fiber-reinforced flexible SiO 2 The aerogel thermal insulation material overcomes the defects of poor mechanical strength, high brittleness and the like of pure aerogel, and can be used as a single block composite material in actual engineering. However, micro-scale reinforcement fibers and nano-scale matrix SiO 2 The interfaces between aerogels are generally mismatched and poorly compatible, and fiber reinforcement does not materially improve SiO 2 The inherent brittleness of the aerogel still has the problems of powder falling and slag falling.
In order to improve SiO on a molecular level 2 The intrinsic brittleness of the aerogel, and the fact that some alkoxy silane containing organic groups is used as a novel precursor to prepare the organic-inorganic in-situ aerogel, the in-situ crosslinking of organic and inorganic units on a molecular level is realized, so that the toughness of the aerogel is improved, and even the aerogel has better compression resilience. The invention patent with patent publication number CN106749378A discloses a mechanical enhanced polysilsesquioxane aerogel, which is characterized in that selected copolymer molecules at least contain one ureido group capable of forming a hydrogen bond, the preparation method comprises the steps of reacting trialkoxysilane containing amino functional groups with organic monomer or oligomer containing isocyanate groups, mixing with a strong polar organic solvent, catalyzing by adopting acid and alkali in two steps, preparing wet gel through sol-gel, and drying to obtain the corresponding aerogel. The patent publication No. CN102372851A discloses a bridged polysilsesquioxane aerogel and a preparation method thereof, wherein the bridged polysilsesquioxane aerogel is obtained by performing a hydrolysis-condensation reaction under an acid catalyst to obtain a bridged polysilsesquioxane sol, gelling, aging and washing the gelled and aged bridged polysilsesquioxane aerogel, and performing supercritical carbon dioxide extraction on the gelled and aged polysilsesquioxane aerogel. Guoqing Zu et al adopt freedomBased on a polymerization/hydrolysis copolycondensation strategy, flexible three-network aerogel based on polyethylene-poly (dimethylsiloxane)/polymethylsilsesquioxane is prepared by drying under normal pressure, and has high specific surface area, super-hydrophobicity, super-elasticity, good bendability and super-heat-insulating property [ Chemistry of Materials,2020,32 (4): 1595 ]. However, these methods generally require an acid catalyst to promote hydrolysis of a silicon source (e.g., hydrochloric acid, nitric acid, etc.), an alkali catalyst to promote condensation polymerization of a gel (e.g., sodium hydroxide, sodium carbonate, ammonia water, etc.), and an acid-base catalyst inevitably causes corrosion damage to equipment, and in addition, organic groups in the alkoxysilane endow the aerogel with good flexibility and simultaneously reduce the reactivity thereof, the sol-gel time is long, and process steps such as aging modification, solvent replacement, etc. are generally required, the process cycle is long, 6 to 10 days are required, a large amount of organic solvent is consumed, and the process is complex.
Therefore, a preparation method with simple process and high efficiency is still needed to synthesize the organic-inorganic hybrid aerogel with excellent comprehensive performance, and further application of the aerogel in the field of heat insulation is promoted.
Disclosure of Invention
Aiming at the problems of complex process, long production period, particularly easy corrosion of acid-base catalysts on production equipment and the like in the prior art, the invention provides an organic-inorganic in-situ hybrid aerogel heat-insulating material with excellent mechanical property and heat-insulating property, and a method for preparing the organic-inorganic in-situ hybrid aerogel heat-insulating material with simple process, high efficiency and no need of acid-base catalysts.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides an organic-inorganic in-situ hybrid aerogel heat-insulating material, wherein the density of aerogel is 0.08-0.30 g/cm 3 The specific surface area is 210.2 to 720.8m 2 The compression strength under 10% strain is 0.4-3.1 MPa, and the thermal conductivity at normal temperature and normal pressure is 0.018-0.029W/(m.K).
A preparation method of the organic-inorganic in-situ hybrid aerogel thermal insulation material comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring an organic solvent and amino bridged siloxane, then adding water (preferably dropwise adding deionized water), and continuously stirring until the mixture is uniform to obtain sol;
(2) Gel
Sealing the sol in the step (1), and standing to obtain gel;
(3) Drying to prepare aerogel
And (3) drying the gel obtained in the step (2) to obtain the organic-inorganic in-situ hybrid aerogel heat-insulating material.
The preparation method of the organic-inorganic in-situ hybrid aerogel heat-insulating material provided by the invention is characterized in that amido-bridged siloxane is used as a silicon source, the organic-inorganic in-situ hybrid aerogel is prepared through an autocatalytic gelling process and a drying process, and the organic-inorganic in-situ hybrid aerogel material which has a nano porous network framework structure, is compressible and resilient and contains C-C, C-N, C-Si and Si-O bonds is obtained, so that the organic-inorganic in-situ hybrid aerogel material has a potential application prospect in the field of heat insulation.
Further, in the step (1), the organic solvent is one or more of ethanol, methanol, acetone, n-heptane and n-hexane.
Further, in the step (1), the amino-bridged siloxane is one or two of bis (3-trimethoxysilylpropyl) amine or bis (3-triethoxysilylpropyl) amine.
Further, in the step (1), the molar ratio of the organic solvent to the amino-bridged siloxane is 6-80, and the molar ratio of the water to the amino-bridged siloxane is 6-15.
Further, in the step (2), the temperature at the time of standing is 30 to 60 ℃ and the time is 0.1 to 24 hours, and the standing is preferably performed in an oven.
Further, in the step (3), the drying refers to carbon dioxide supercritical fluid drying, ethanol supercritical fluid drying or vacuum freeze drying.
Further, the drying of the carbon dioxide supercritical fluid is to replace the solvent in the gel with ethanol, place the gel in a drying device of the carbon dioxide supercritical fluid, raise the pressure and the temperature, and dry the gel for 12 to 96 hours at the pressure of 10 to 20MPa and the temperature of 35 to 55 ℃.
Further, the ethanol supercritical fluid drying is to replace the solvent in the gel with ethanol, place the gel in ethanol supercritical fluid drying equipment, raise the pressure and the temperature, and dry the gel for 12 to 72 hours by using carbon dioxide supercritical fluid under the conditions of the pressure of 7 to 10MPa and the temperature of 245 to 265 ℃.
Further, the vacuum freeze drying is to replace the organic solvent in the gel with deionized water, pre-freeze the gel at the temperature of minus 80 to minus 40 ℃, and then carry out vacuum freeze drying for 24 to 96 hours at the vacuum degree of 5 to 15Pa and the temperature of minus 60 to minus 20 ℃.
In the step (1), the autocatalytic hydrolysis and polycondensation of the silicon source can be realized by using the amino-bridged siloxane as the silicon source. The amido in the amido bridged siloxane has strong electron-withdrawing property, and the deionized water added after the attack makes the amido bridged siloxane generate hydroxide radicals, and the hydroxide radicals promote the hydrolysis and polycondensation of alkoxy in the amido bridged siloxane, thereby completing the autocatalytic gel without an acid-base catalyst.
In the step (2), the autocatalytic hydrolysis and polycondensation reaction of the silicon source are rapidly carried out by heat preservation in an oven, the crosslinking of the nano particles is accelerated to form a three-dimensional nano network skeleton structure, the formation of gel is promoted, the sol-gel reaction time is shortened, the reaction degree of siloxane groups is improved by the increase of the temperature, the strength of the skeleton structure is enhanced, and the prepared organic-inorganic in-situ hybrid aerogel has excellent mechanical properties.
In the step (3), the carbon dioxide supercritical fluid drying and the ethanol supercritical fluid drying are adopted, so that the influence of capillary force on the structure of the nanometer framework in the drying process can be completely eliminated, the material is basically not shrunk, the aerogel structure of the three-dimensional nanometer network framework can be well maintained, but compared with a vacuum freeze drying process, the cost is higher, and the high-temperature high-pressure risk coefficient is large. The vacuum freeze-drying process can directly sublimate the solidified deionized water into a gaseous state, the problem that the pore structure is damaged by capillary force is solved by changing a gas-liquid interface into a gas-solid interface at low temperature and low pressure, however, the deionized water can expand in a certain volume in the solidification process, the skeleton structure of the organic-inorganic in-situ hybrid aerogel can be damaged to a certain extent, the strength of the aerogel is reduced, the micro-aperture of the organic-inorganic in-situ hybrid aerogel prepared by vacuum freeze-drying is generally in a micron level, and compared with the carbon dioxide supercritical fluid drying process and the ethanol supercritical fluid drying process, the heat insulation effect that the nano-pore structure inhibits gaseous heat transfer can be weakened to a certain extent.
Compared with the prior art, the invention has the following advantages:
1. according to the preparation method of the organic-inorganic in-situ hybrid aerogel heat-insulating material, provided by the invention, the amino-bridged siloxane is used as a silicon source, the reaction activity is high, the gel can be self-catalyzed without adding an acid-base catalyst, the production period is short, the process is simple, the production efficiency is high, and the problem that the equipment is easy to corrode due to the acid-base catalyst in the traditional process is avoided. Compared with the traditional preparation method with the production period as long as 6-10 days, the preparation method provided by the invention has the period of 1-5 days.
2. The preparation method of the organic-inorganic in-situ hybrid aerogel heat-insulating material provided by the invention takes amino-bridged siloxane as a silicon source, and realizes in-situ hybrid crosslinking of organic groups and inorganic groups. The organic group flexible chain segment endows the prepared organic-inorganic in-situ hybrid aerogel with good compression resilience performance, and the compression resilience strain can reach 20%. And the in-situ hybridization of inorganic groups ensures that the prepared organic-inorganic in-situ hybridization aerogel has better temperature resistance and basically keeps stable at the temperature of below 400 ℃.
3. The density of the organic-inorganic in-situ hybrid aerogel heat-insulating material provided by the invention is 0.08-0.30 g/cm 3 The specific surface area is 210.2 to 720.8m 2 The compressive strength under 10 percent strain is 0.4-3.1 MPa, the thermal conductivity at normal temperature and normal pressure is 0.018-0.029W/(m.K), and the composite material has good mechanical property and excellent heat-insulating property.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic process flow diagram of a preparation method of an organic-inorganic in-situ hybrid aerogel thermal insulation material provided by the invention.
FIG. 2 is a TG-DTG curve of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in example 1 of the present invention.
FIG. 3 is a compressive strain-stress curve of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in example 1 of the present invention.
FIG. 4 is an infrared spectrum of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in example 1 of the present invention.
Detailed Description
Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.
It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every intervening value, to the extent any stated or intervening value in a stated range, and every other stated or intervening value in that stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.
As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.
Example 1
A preparation method of an organic-inorganic in-situ hybrid aerogel heat-insulating material is shown in a process flow diagram in figure 1 and specifically comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring ethanol and bis (3-trimethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until the mixture is uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: ethanol: bis (3-trimethoxysilylpropyl) amine =40; deionized water: bis (3-trimethoxysilylpropyl) amine =8;
(2) Gel
Sealing the sol prepared in the step (1), placing the sealed sol into an oven, standing for 12 hours, wherein the temperature of the oven is 40 ℃, taking out, and cooling to obtain gel;
(3) Drying to prepare aerogel
And (3) performing carbon dioxide supercritical fluid drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the carbon dioxide supercritical fluid drying is to replace the solvent in the gel with ethanol, place the gel in carbon dioxide supercritical fluid drying equipment, perform carbon dioxide supercritical fluid drying for 48 hours under the conditions of pressure of 10MPa and temperature of 45 ℃ after pressure and temperature rise to obtain the organic-inorganic in-situ hybrid aerogel.
The organic and inorganic materials prepared in this exampleThe density of the in-situ hybrid aerogel thermal insulation material is 0.18g/cm 3 The specific surface area is 525.8m 2 The compressive strength under 10% strain is 0.8MPa, and the thermal conductivity at normal temperature and normal pressure is 0.025W/(m.K).
The TG-DTG curve of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is shown in FIG. 2, which shows that the thermal insulation material has good temperature resistance and basically keeps stable below 400 ℃; the compressive strain-stress curve of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is shown in fig. 3, which shows that the thermal insulation material has excellent compressive resilience performance, and the compressive resilience strain can reach 20%; an infrared spectrogram of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is shown in FIG. 4, which shows that the material contains chemical bonds of C-C, C-N, C-Si, si-O and the like.
Example 2
A preparation method of an organic-inorganic in-situ hybrid aerogel heat-insulating material is shown in a process flow diagram in figure 1 and specifically comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring acetone and bis (3-triethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: acetone: bis (3-triethoxysilylpropyl) amine =60; deionized water: bis (3-triethoxysilylpropyl) amine =10;
(2) Gel
Sealing the sol prepared in the step (1), placing the sealed sol into an oven, standing for 24 hours, wherein the temperature of the oven is 50 ℃, taking out, and cooling to obtain gel;
(3) Drying to prepare aerogel
And (3) performing ethanol supercritical fluid drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the ethanol supercritical fluid drying is to replace the solvent in the gel with ethanol and place the gel in ethanol supercritical fluid drying equipment, and after the pressure and the temperature are increased, performing carbon dioxide supercritical fluid drying for 60 hours under the conditions of the pressure of 8MPa and the temperature of 255 ℃ to obtain the organic-inorganic in-situ hybrid aerogel.
The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is 0.15g/cm 3 The specific surface area is 660.1m 2 (iv)/g, compressive strength at 10% strain of 0.6MPa, and thermal conductivity at normal temperature and pressure of 0.024W/(m.K).
Example 3
A preparation method of an organic-inorganic in-situ hybrid aerogel heat-insulating material is shown in a process flow diagram in figure 1 and specifically comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring n-heptane and bis (3-triethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: n-heptane: bis (3-triethoxysilylpropyl) amine =80; deionized water: bis (3-triethoxysilylpropyl) amine =6;
(2) Gel
Sealing the sol prepared in the step (1), placing the sealed sol into an oven, standing for 24 hours, wherein the temperature of the oven is 60 ℃, taking out, and cooling to obtain gel;
(3) Drying to prepare aerogel
And (3) performing carbon dioxide supercritical fluid drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the carbon dioxide supercritical fluid drying is to replace the solvent in the gel with ethanol, place the gel in carbon dioxide supercritical fluid drying equipment, perform carbon dioxide supercritical fluid drying for 96 hours under the conditions of pressure of 12MPa and temperature of 45 ℃ after pressure and temperature rise, and obtain the organic-inorganic in-situ hybrid aerogel.
The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is 0.08g/cm 3 The specific surface area is 516.7m 2 (iv) g, compressive strength at 10% strain of 0.4MPa, and thermal conductivity at room temperature and normal pressure of 0.021W/(m.K).
Example 4
A preparation method of an organic-inorganic in-situ hybrid aerogel heat-insulating material is shown in a process flow diagram in figure 1 and specifically comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring ethanol and bis (3-trimethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until the mixture is uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: ethanol: bis (3-trimethoxysilylpropyl) amine =6; deionized water: bis (3-trimethoxysilylpropyl) amine =15;
(2) Gel
Sealing the sol prepared in the step (1), placing the sealed sol into a drying oven, standing for 10 hours, taking out the sol and cooling to obtain gel, wherein the temperature of the drying oven is 60 ℃;
(3) Drying to prepare aerogel
And (3) performing ethanol supercritical fluid drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the ethanol supercritical fluid drying is to replace the solvent in the gel with ethanol and place the gel in ethanol supercritical fluid drying equipment, and after the pressure and the temperature are increased, performing carbon dioxide supercritical fluid drying for 60 hours under the conditions of the pressure of 8MPa and the temperature of 255 ℃ to obtain the organic-inorganic in-situ hybrid aerogel.
The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is 0.30g/cm 3 The specific surface area is 253.4m 2 (iv) g, a compressive strength at 10% strain of 3.0MPa, and a thermal conductivity at normal temperature and pressure of 0.029W/(m.K).
Example 5
A preparation method of an organic-inorganic in-situ hybrid aerogel heat-insulating material is shown in a process flow diagram in figure 1 and specifically comprises the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring normal hexane and bis (3-trimethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until the deionized water is uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: n-hexane: bis (3-trimethoxysilylpropyl) amine =6; deionized water: bis (3-trimethoxysilylpropyl) amine =15;
(2) Gel
Sealing the sol prepared in the step (1), placing the sealed sol into a drying oven, standing for 10 hours, taking out the sol and cooling to obtain gel, wherein the temperature of the drying oven is 60 ℃;
(3) Drying to prepare aerogel
And (3) performing vacuum freeze-drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the vacuum freeze-drying is to replace n-hexane in the gel with deionized water and pre-freeze the gel at the temperature of-80 ℃, and then perform vacuum freeze-drying for 96 hours at the vacuum degree of 5Pa and the temperature of-20 ℃ to obtain the organic-inorganic in-situ hybrid aerogel.
The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the embodiment is 0.22g/cm 3 Specific surface area of 210.2cm 2 (iv) g, a compressive strength at 10% strain of 1.3MPa, and a thermal conductivity at normal temperature and pressure of 0.029W/(m.K).
Comparative example 1
The difference from example 1 is that the sol prepared in step (1) is not sealed and then placed in an oven at 40 ℃ during the gelation in step (2), and the specific process is as follows: and (2) sealing the sol prepared in the step (1), and standing at room temperature for 48h to obtain gel.
Because the aerogel is not put into an oven to be preserved by Wen Ningjiao, the gelation time is long, and the strength of the prepared aerogel is low. The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared in the comparative example was 0.19g/cm 3 The specific surface area is 375.1m 2 G, compressive strength at 10% strain of 0.5MPa, and thermal conductivity at normal temperature and pressure of 0.027W/(m.K).
Comparative example 2
The difference from example 1 is that the step (3) is dried to prepare the aerogel under normal pressure (i.e. one atmosphere), and the specific process is as follows: and (3) carrying out normal pressure drying treatment on the gel prepared in the step (2) to prepare the organic-inorganic in-situ hybrid aerogel, wherein the normal pressure drying is to place the gel in a drying oven, and each temperature point is set to be 4h by adopting a gradient heating mode of 30-40-50-60-70-80-90-100 ℃, so that the organic-inorganic in-situ hybrid aerogel is finally obtained.
Because of adopting the normal pressure drying, the gel has serious shrinkage and low specific surface area in the drying processPoor heat insulation performance. The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared by the comparative example is 0.38g/cm 3 Specific surface area of 83.2m 2 The material is broken under 4.6% strain, the maximum compression strength is 3.9MPa, and the thermal conductivity at normal temperature and normal pressure is 0.047W/(m.K).
Comparative example 3
The difference from example 1 is only that when the sol is prepared in step (1), the molar ratio of the organic solvent to the amino-bridged siloxane is 90, and the specific process is as follows: firstly, fully and uniformly stirring ethanol and bis (3-trimethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until the mixture is uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: ethanol: bis (3-trimethoxysilylpropyl) amine =90; deionized water: bis (3-trimethoxysilylpropyl) amine =8.
Due to the excessive content of the organic solvent, the content of the amino-bridged siloxane is too low, so that the strength of the prepared aerogel is low. The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared by the comparative example is 0.05g/cm 3 The specific surface area is 195.8m 2 The material is broken under 5.9% strain, the maximum compression strength is 0.1MPa, and the thermal conductivity at normal temperature and normal pressure is 0.031W/(m.K).
Comparative example 4
The difference from example 1 is only that when the sol is prepared in step (1), the molar ratio of water to amino-bridged siloxane is 16, and the specific process is as follows: firstly, fully and uniformly stirring ethanol and bis (3-trimethoxysilylpropyl) amine, then dropwise adding deionized water, and continuously stirring until the mixture is uniform to obtain sol, wherein the molar ratio of the raw materials is as follows: ethanol: bis (3-trimethoxysilylpropyl) amine =40; deionized water: bis (3-trimethoxysilylpropyl) amine =16.
Due to the fact that the water content is too high, the hydrolytic polycondensation reaction of the amino-bridged siloxane is too fast, gel is not uniform, and the prepared aerogel is low in strength and poor in heat conductivity. The density of the organic-inorganic in-situ hybrid aerogel thermal insulation material prepared by the comparative example is 0.21g/cm 3 The specific surface area is 427.6m 2 G, compressive strength at 10% strain of 0.6MPa, usualWen Changya thermal conductivity was 0.027W/(m.K).
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (10)
1. An organic-inorganic in-situ hybrid aerogel heat-insulating material is characterized in that the density of aerogel is 0.08-0.30 g/cm 3 The specific surface area is 210.2 to 720.8m 2 The compression strength under 10% strain is 0.4-3.1 MPa, and the thermal conductivity at normal temperature and normal pressure is 0.018-0.029W/(m.K).
2. A preparation method of the organic-inorganic in-situ hybrid aerogel thermal insulation material of claim 1, which is characterized by comprising the following steps:
(1) Compounding sol
Firstly, fully and uniformly stirring an organic solvent and amino bridged siloxane, then adding water, and continuously stirring until the mixture is uniform to obtain sol;
(2) Gel
Sealing the sol in the step (1), and standing to obtain gel;
(3) Drying to prepare aerogel
And (3) drying the gel obtained in the step (2) to obtain the organic-inorganic in-situ hybrid aerogel heat-insulating material.
3. The method according to claim 2, wherein in the step (1), the organic solvent is one or more selected from the group consisting of ethanol, methanol, acetone, n-heptane and n-hexane.
4. The method according to claim 2, wherein in step (1), the amino-bridged siloxane is one or both of bis (3-trimethoxysilylpropyl) amine and bis (3-triethoxysilylpropyl) amine.
5. The method according to claim 2, wherein in the step (1), the molar ratio of the organic solvent to the amino-bridged siloxane is 6 to 80, and the molar ratio of the water to the amino-bridged siloxane is 6 to 15.
6. The method according to claim 2, wherein the temperature of the standing in the step (2) is 30 to 60 ℃ and the time is 0.1 to 24 hours.
7. The method according to claim 2, wherein the drying in the step (3) is carbon dioxide supercritical fluid drying, ethanol supercritical fluid drying or vacuum freeze drying.
8. The preparation method according to claim 7, wherein the drying of the carbon dioxide supercritical fluid is carried out by replacing the solvent in the gel with ethanol, placing the gel into a carbon dioxide supercritical fluid drying device, and drying the gel for 12 to 96 hours under the conditions of pressure of 10 to 20MPa and temperature of 35 to 55 ℃ after increasing the pressure and temperature.
9. The preparation method of claim 7, wherein the ethanol supercritical fluid drying is that the solvent in the gel is replaced by ethanol, the gel is placed in ethanol supercritical fluid drying equipment, and the carbon dioxide supercritical fluid drying is carried out for 12 to 72 hours under the conditions of pressure of 7 to 10MPa and temperature of 245 to 265 ℃ after the pressure and the temperature are increased.
10. The preparation method of claim 7, wherein the vacuum freeze-drying is to replace the organic solvent in the gel with deionized water, pre-freeze the gel at a temperature of-80 to-40 ℃, and then carry out vacuum freeze-drying for 24 to 96 hours at a vacuum degree of 5 to 15Pa and a temperature of-60 to-20 ℃.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116876111A (en) * | 2023-07-20 | 2023-10-13 | 中国人民解放军海军工程大学 | High-temperature-resistant ceramic aerogel fiber and preparation method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012062341A (en) * | 2010-09-14 | 2012-03-29 | Konica Minolta Holdings Inc | Heat insulating sheet |
| CN103754886A (en) * | 2013-12-17 | 2014-04-30 | 同济大学 | Preparation method for composite silica aerogel with ultra high strength and high specific surface area |
| CN104341594A (en) * | 2014-10-20 | 2015-02-11 | 同济大学 | Preparation method of crosslinked polyimide silicon dioxide mixed gas gel |
| US20160369936A1 (en) * | 2013-07-05 | 2016-12-22 | Amogreentech Co., Ltd. | Thermal insulation sheet, hybrid thermal insulation sheet, and thermal insulation panel |
| CN110092939A (en) * | 2019-05-06 | 2019-08-06 | 中国人民解放军国防科技大学 | Polyorganoalkoxysilane-reinforced hybrid silica aerogel and method for producing same |
| CN110845840A (en) * | 2019-11-20 | 2020-02-28 | 界首市睿阳塑胶科技有限公司 | Preparation method of lightweight aerogel life buoy filling material |
| DE102018128410A1 (en) * | 2018-11-13 | 2020-05-14 | Fraunhofer Gesellschaft zur Förderung der angewandten Forschung e.V. | Process for the production of aerogels and aerogels obtainable therewith |
| CN111499919A (en) * | 2020-05-11 | 2020-08-07 | 江西理工大学 | Biomass fiber hybrid polysiloxane aerogel glass and preparation method thereof |
-
2022
- 2022-10-08 CN CN202211222143.8A patent/CN115466518B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012062341A (en) * | 2010-09-14 | 2012-03-29 | Konica Minolta Holdings Inc | Heat insulating sheet |
| US20160369936A1 (en) * | 2013-07-05 | 2016-12-22 | Amogreentech Co., Ltd. | Thermal insulation sheet, hybrid thermal insulation sheet, and thermal insulation panel |
| CN103754886A (en) * | 2013-12-17 | 2014-04-30 | 同济大学 | Preparation method for composite silica aerogel with ultra high strength and high specific surface area |
| CN104341594A (en) * | 2014-10-20 | 2015-02-11 | 同济大学 | Preparation method of crosslinked polyimide silicon dioxide mixed gas gel |
| DE102018128410A1 (en) * | 2018-11-13 | 2020-05-14 | Fraunhofer Gesellschaft zur Förderung der angewandten Forschung e.V. | Process for the production of aerogels and aerogels obtainable therewith |
| CN110092939A (en) * | 2019-05-06 | 2019-08-06 | 中国人民解放军国防科技大学 | Polyorganoalkoxysilane-reinforced hybrid silica aerogel and method for producing same |
| CN110845840A (en) * | 2019-11-20 | 2020-02-28 | 界首市睿阳塑胶科技有限公司 | Preparation method of lightweight aerogel life buoy filling material |
| CN111499919A (en) * | 2020-05-11 | 2020-08-07 | 江西理工大学 | Biomass fiber hybrid polysiloxane aerogel glass and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 周祥发;冯坚;肖汉宁;张长瑞;姜勇刚;: "二氧化硅气凝胶隔热复合材料的性能及其瞬态传热模拟", 国防科技大学学报 * |
| 蒲敏,周根树,郑茂盛,金志浩: "硅气凝胶功能材料的制备及应用", 化工进展 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116876111A (en) * | 2023-07-20 | 2023-10-13 | 中国人民解放军海军工程大学 | High-temperature-resistant ceramic aerogel fiber and preparation method thereof |
| CN116876111B (en) * | 2023-07-20 | 2024-05-03 | 中国人民解放军海军工程大学 | High-temperature-resistant ceramic aerogel fiber and preparation method thereof |
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