CN108975947A - A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite - Google Patents
A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite Download PDFInfo
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- CN108975947A CN108975947A CN201810939612.5A CN201810939612A CN108975947A CN 108975947 A CN108975947 A CN 108975947A CN 201810939612 A CN201810939612 A CN 201810939612A CN 108975947 A CN108975947 A CN 108975947A
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- sio
- aeroge
- carbon foam
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- hollow carbon
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B30/00—Compositions for artificial stone, not containing binders
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
- C04B38/08—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by adding porous substances
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/30—Mortars, concrete or artificial stone characterised by specific physical values for heat transfer properties such as thermal insulation values, e.g. R-values
- C04B2201/32—Mortars, concrete or artificial stone characterised by specific physical values for heat transfer properties such as thermal insulation values, e.g. R-values for the thermal conductivity, e.g. K-factors
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Carbon And Carbon Compounds (AREA)
- Ceramic Products (AREA)
Abstract
The invention discloses a kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite, by hollow carbon foam framework, SiC coating and SiO2Aeroge protective shell is constituted, and hollow carbon foam framework is in three-dimensional netted interconnection, is made of three-dimensional nodes and fibrous hollow tube；SiC coating uniform is coated on hollow carbon foam framework outer wall, SiC coating dense uniform；SiO2Aeroge protective shell is by the SiO that is uniformly filled in hollow carbon foam framework hole2The thermally treated volume contraction of aeroge obtains after reuniting.The present invention is enhanced using SiC coating first using hollow carbon foam framework as matrix, prevents SiO2Aeroge is shunk in ageing process so that framework collapse, while SiO2Aeroge is thermally treated, SiO2Hole reduces between monomer particle, SiO2Cluster volume contraction is simultaneously reunited, and obtains SiO in SiC coating surface2Aeroge protective shell improves the structural strength of material while protecting SiC coating.
Description
Technical field
The present invention relates to a kind of SiO2Aerogel composite, more particularly to a kind of low thermally conductive SiO of high-temperature-resistant high2Gas
Gel complex material.
Background technique
Carbon foam is obtained the 1960s using cracking thermosetting resin by Walter Ford first,
It is broadly divided into reticulated vitreous carbon foam material and two kinds of graphitic carbon material.Netted hollow foam is a kind of hollow bone
The light porous material with tridimensional network of frame and the vestibule composition of nano wire segmentation, density is about 30~200mg/
cm3, there is low-density, low thermal coefficient of expansion, high thermal shock performance and lower thermal coefficient, in heat-barrier material, battery
Electrode material and field of aerospace application have bright prospects.But since the hole in such carbon foam is larger,
Aperture is between 300~900 microns, to improve the gaseous heat transfer of material.In order to further decrease the heat of carbon foam
Conductance improves its heat-proof quality, can introduce aerogel material inside its hole.
Nano-porous materials made of aeroge is mutually assembled as a kind of nano particle, solid skeleton is by nano particle
Be crosslinked, aperture between several nanometers to tens nanometers, have many special properties, as high-specific surface area, low-density and
High porosity, thus have a wide range of applications in heat-insulated, absorption and catalytic field.Due to the uniqueness in structure, airsetting
Glue mechanics, acoustics, calorifics, optics, in terms of there are many special properties, such as: minimum thermal conductivity, apparent close
Degree, high specific surface area, porosity etc..In terms of thermal insulation applications, that most study is SiO at present2Aeroge, room temperature
Minimum reachable 0.013 W/ (mK) of thermal conductivity, than the thermal conductivity (0.026 W/ (mK)) of the air under stationary state also than
It is low, belong to the scope of ultra heat insulating material.Therefore by SiO2Aeroge and carbon foam progress are compound, not only can solve carbon
The higher problem of foamed material gas phase heat transfer, and overcome SiO2The low problem of aerogel material intensity.
Application No. is 201410391902.2 Chinese invention patents to disclose a kind of filling SiO2The carbon airsetting of aeroge
The preparation method of glue, it is characterised in that include the steps that following sequences: (1) preparation of carbon aerogels: with resorcinol (R) and first
Aldehyde (F) is presoma (molar ratio R: F=1: 2), and natrium carbonicum calcinatum is catalyst, and carbon foam skeleton is prepared using carbon foam as base
Carbon aerogels.(2) carbon aerogels surface acid etching: by H2O2∶NH3H2O∶H2O according to 1: 1: 5 volume ratio be made into mixing it is molten
Liquid immerses above-mentioned carbon aerogels in the mixed solution, keeps 1h under 90 DEG C of water bath condition.(3)SiO2Precursor solution
The carbon aerogels that preparation and carbon aerogels immerse precursor solution aging, are dried to obtain filling aerosil.The preparation
Method is reliable, has a safety feature, and composite aerogel obtained had not only maintained the benefit performance of aeroge, but also enhanced aeroge
Mechanical property；Plural gel surface hydrophobicity is not easy to absorb the moisture in air, and shrinkage is small, but uses aeroge as bone
Frame, structural strength have the defects that certain.
Application No. is 201410391903.7 Chinese invention patents to disclose a kind of carbon gel/SiO2The compound airsetting of gel
Glue, by the carbon gel/SiO filled in carbon foam skeleton and matrix porosity2Gel forms, wherein carbon foam skeleton volume accounting 10
~ 60%, the density of composite aerogel is 0.05 ~ 0.1g/m3, thermal conductivity≤0.8W/ (mK).The carbon foam skeleton has
Open-celled structure, porosity are 90% ~ 97%, and aperture is 10 ~ 1000 microns.The carbon gel or SiO2Gel has mesoporous receive
Rice micro-sphere structure, aperture are 2 ~ 100 nanometers, and density is 0.1 ~ 0.5mg/cm3, the discrete hole wall for being distributed in carbon foam skeletal support
In, filling rate is 70 ~ 95%.The composite aerogel can be greatly lowered that porous material bring heat radiation itself is biggish to ask
Topic, thermal conductivity will not sharply increase as the temperature rises, and have the characteristics that lightweight, high temperature resistant and thermal coefficient are low,
Various Large Complicated Structural Components can be made, form thermal protection structure resistant to high temperature.
Application No. is 201410743407.3 Chinese invention patents to disclose a kind of high temperature resistance and high strength SiC carbon coated bubble
Foam composite heat-insulated material and preparation method thereof, be related to a kind of high temperature resistance and high strength SiC cladding carbon foam composite heat-insulated material and its
Preparation method.The high temperature resistance and high strength SiC cladding carbon foam composite heat-insulated material is one kind by carbon foam and silicon carbide gas
Gel is constituted；Temperature tolerance improves about 100 DEG C than pure carbon foam, apparent density exists at 690 ~ 700 DEG C in its air atmosphere
0.4~0.6g/cm3, compression strength is in 11 ~ 15MPa, and room temperature thermal conductivity is at 0.4 ~ 0.6W/ (mK).Preparation method is dioxy
SiClx colloidal sol is injected into the hole of carbon foam, by sol-gel, aging and the oxidation for being dried to obtain carbon foam enhancing
Then silica aerogel composite heat-insulated material carries out high-temperature heat treatment under inert atmosphere protection, to prepare a kind of high temperature resistant
High-intensitive SiC coats carbon foam composite heat-insulated material.The invention has the advantages that materials are simple and technique is simple and direct, technical process behaviour
Make simple, large-scale production easy to accomplish.
Application No. is 201710115403.4 Chinese invention patents to disclose a kind of high temperature resistant foam enhancing SiO2Airsetting
Glue heat-insulating material and preparation method thereof, which is characterized in that the high temperature resistant enhances SiO2Aerogel insulating material includes carbon bubble
Foam reinforcement, latticed silicon carbide nanometer line, SiO2Aeroge, latticed silicon carbide nanometer line filling segmentation carbon foam internal holes
Gap space, SiO2Aeroge is uniformly filled in carbon foam reinforcement, and density is 0.05~0.15g/cm3, porosity is greater than 90%.
Carbon foam reinforcement is flexible carbon foam, is obtained by melamine foamed plastic high temperature pyrolysis, latticed silicon carbide nanometer line, diameter is
50~20nm.Chemical vapor deposition prepares silicon carbide/carbon composite foam, prepares SiO using constant pressure and dry technology2Aeroge is in turn
Obtain high temperature resistant foam enhancing SiO2Aerogel insulating material.The invention this have the advantage that netted SiC nanowire support carbon bone
Frame improves composite materials property, while silicon carbide nanometer line reduces foam aperture, reduces the thermal conductivity of material.
Such as above-mentioned several patents, the relevant technical products in this field are disclosed, but carbon foam brittleness is big, is directly used as
Aeroge skeleton easily collapses, and causes to damage to material, in addition less to the intensity of aerogel composite and heatproof Journal of Sex Research, because
This, urgent need develops that a kind of heat resistance is more preferable, structural strength is higher, the lower SiO of thermal coefficient2Aerogel composite.
Summary of the invention
The purpose of the present invention overcomes the shortcomings of the prior art, and provides a kind of high-temperature-resistant high low thermally conductive SiO2Aeroge
Composite material.
The technical solution adopted to achieve the purpose of the present invention is: a kind of low thermally conductive SiO of high-temperature-resistant high2Aeroge is multiple
Condensation material, by hollow carbon foam framework, SiC coating and SiO2Aeroge protective shell is constituted, it is characterised in that the hollow carbon
Foam framework volume accounting 20 ~ 40%, the SiC coating volume accounting 5 ~ 10%, the SiO2Aeroge protects shell volume
Accounting 50 ~ 75%；The hollow carbon foam framework is in three-dimensional netted interconnection, is made of three-dimensional nodes and fibrous hollow tube, fine
Hollow 10 ~ 20 nanometers of wall thickness of shape of dimension is compact structure at three-dimensional nodes；The SiC coating uniform is coated on hollow carbon foam
Skeleton outer wall, SiC coating dense uniform, with a thickness of 10 ~ 20 microns；The SiO2Aeroge protective shell is hollow by being uniformly filled in
SiO in carbon foam matrix porosity2The thermally treated volume contraction of aeroge obtains after reuniting, SiO2Hole is between aerogel particle
0.1 ~ 1 nanometer.
Further, the hollow carbon foam framework has open-celled structure, and porosity is 95 ~ 99%, and aperture size is
10~1000 microns, discrete distribution.
Further, the SiO2Aeroge after heat treatment SiO2Monomer particle radius of curvature increases, and particle volume increases
Greatly, inter-granular porosity reduces, SiO2Cluster volume contraction is simultaneously reunited, obtained SiO2Aeroge protective shell is coated on SiC coating appearance
Face.
Further, the aerogel composite apparent density is 0.5~0.8 g/cm3, compression strength be 16~
20MPa, room temperature thermal conductivity are 0.030~0.040 W/ (mK), and temperature tolerance is 600~680 DEG C in air atmosphere.
The beneficial effects of the present invention are: (1) present invention using hollow carbon foam framework as matrix, first using SiC coating into
Row enhancing, prevents SiO2Aeroge is shunk in ageing process so that framework collapse, while significantly improving the compression performance of material
And antioxygenic property；(2) SiO2Aeroge is thermally treated, SiO2Hole reduces between monomer particle, SiO2Cluster volume contraction is simultaneously rolled into a ball
It is poly-, SiO is obtained in SiC coating surface2Aeroge protective shell, while protecting SiC coating, the structure for improving material is strong
Degree；(3) present invention has both the hollow reticular structure and SiO of carbon foam skeleton2The heat-insulated heat-insulating property of aeroge, has excellent performance,
It can be applied under extreme environment.
Specific embodiment
Combined with specific embodiments below, the present invention is furture elucidated, it should be understood that these embodiments are merely to illustrate the present invention
Rather than limit the scope of the invention, after the present invention has been read, those skilled in the art are to various equivalences of the invention
It is as defined in the appended claims that the modification of form falls within the application.
Embodiment
A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite, by hollow carbon foam framework, SiC coating and SiO2
Aeroge protective shell is constituted, it is characterised in that the hollow carbon foam framework volume accounting 20%, the SiC coating volume
Accounting 10%, the SiO2Aeroge protects shell volume accounting 70%；The hollow carbon foam framework is in three-dimensional netted interconnection,
It is made of three-dimensional nodes and fibrous hollow tube, hollow 10 nanometers of wall thickness of threadiness, is compact structure at three-dimensional nodes；Described
SiC coating uniform is coated on hollow carbon foam framework outer wall, SiC coating dense uniform, with a thickness of 15 microns；The SiO2Airsetting
Glue protective shell is by the SiO that is uniformly filled in hollow carbon foam framework hole2The thermally treated volume contraction of aeroge obtains after reuniting
It arrives, SiO2Hole is 0.5 nanometer between aerogel particle.
Further, the hollow carbon foam framework have open-celled structure, porosity 96%, aperture size be 10~
It 1000 microns, is in a discrete distribution.
Further, the SiO2Aeroge after heat treatment SiO2Monomer particle radius of curvature increases, and particle volume increases
Greatly, inter-granular porosity reduces, SiO2Cluster volume contraction is simultaneously reunited, obtained SiO2Aeroge protective shell is coated on SiC coating appearance
Face.
Further, the aerogel composite apparent density is 0.62 g/cm3, compression strength 18.9MPa,
Room temperature thermal conductivity is 0.032 W/ (mK), and temperature tolerance is 675 DEG C in air atmosphere.
It above are only the specific embodiment of the present invention, but the design concept of the present invention is not limited to this, all benefits
It is made a non-material change to the present invention with this design, should belong to the behavior for invading the scope of protection of the invention.But it is all
Without departing from the content of technical solution of the present invention, according to the technical essence of the invention any type of letter to the above embodiments
Single modification, equivalent variations and remodeling, still fall within the protection scope of technical solution of the present invention.
Claims (4)
1. a kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite, by hollow carbon foam framework, SiC coating and SiO2Gas
Gel protective shell is constituted, it is characterised in that the hollow carbon foam framework volume accounting 20 ~ 40%, the SiC coating volume
Accounting 5 ~ 10%, the SiO2Aeroge protects shell volume accounting 50 ~ 75%；The hollow carbon foam framework is in three-dimensional netted
Interconnection is made of three-dimensional nodes and fibrous hollow tube, and hollow 10 ~ 20 nanometers of wall thickness of threadiness, be closely knit knot at three-dimensional nodes
Structure；The SiC coating uniform is coated on hollow carbon foam framework outer wall, SiC coating dense uniform, with a thickness of 10 ~ 20 microns；
The SiO2Aeroge protective shell is by the SiO that is uniformly filled in hollow carbon foam framework hole2The thermally treated volume of aeroge is received
Contracting obtains after reuniting, SiO2Hole is 0.1 ~ 1 nanometer between aerogel particle.
2. SiO according to claim 12Aerogel composite, it is characterised in that the hollow carbon foam framework has
Open-celled structure, porosity are 95 ~ 99%, and aperture size is 10~1000 microns, are in a discrete distribution.
3. SiO according to claim 12Aerogel composite, it is characterised in that the SiO2Aeroge is thermally treated
SiO afterwards2Monomer particle radius of curvature increases, and particle volume increases, and inter-granular porosity reduces, SiO2Cluster volume contraction is simultaneously reunited, and is obtained
The SiO arrived2Aeroge protective shell is coated on SiC coating outer surface.
4. SiO according to claim 12Aerogel composite, it is characterised in that the aerogel composite is apparent
Density is 0.5~0.8 g/cm3, compression strength is 16~20MPa, and room temperature thermal conductivity is 0.030~0.040 W/ (mK),
Temperature tolerance is 600~680 DEG C in air atmosphere.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810939612.5A CN108975947A (en) | 2018-08-17 | 2018-08-17 | A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite |
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| CN201810939612.5A CN108975947A (en) | 2018-08-17 | 2018-08-17 | A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109569451A (en) * | 2019-01-17 | 2019-04-05 | 苏州宏久航空防热材料科技有限公司 | A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite |
| CN113773043A (en) * | 2021-07-14 | 2021-12-10 | 中国科学院金属研究所 | Preparation method of low-density carbon fiber reinforced carbon aerogel composite material |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104478475A (en) * | 2014-12-08 | 2015-04-01 | 南京工业大学 | High-temperature-resistant high-strength SiC-coated carbon foam composite heat-insulating material and preparation method thereof |
| CN107200600A (en) * | 2017-07-24 | 2017-09-26 | 苏州宏久航空防热材料科技有限公司 | A kind of foam C-base composte material with low thermal conductivity |
-
2018
- 2018-08-17 CN CN201810939612.5A patent/CN108975947A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104478475A (en) * | 2014-12-08 | 2015-04-01 | 南京工业大学 | High-temperature-resistant high-strength SiC-coated carbon foam composite heat-insulating material and preparation method thereof |
| CN107200600A (en) * | 2017-07-24 | 2017-09-26 | 苏州宏久航空防热材料科技有限公司 | A kind of foam C-base composte material with low thermal conductivity |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109569451A (en) * | 2019-01-17 | 2019-04-05 | 苏州宏久航空防热材料科技有限公司 | A kind of low thermally conductive SiO of high-temperature-resistant high2Aerogel composite |
| CN113773043A (en) * | 2021-07-14 | 2021-12-10 | 中国科学院金属研究所 | Preparation method of low-density carbon fiber reinforced carbon aerogel composite material |
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