CN106630931B - Preparation method of wave-transparent and heat-insulating integrated fiber-reinforced Al2O3-SiO2 aerogel material - Google Patents
Preparation method of wave-transparent and heat-insulating integrated fiber-reinforced Al2O3-SiO2 aerogel material Download PDFInfo
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- CN106630931B CN106630931B CN201610885973.7A CN201610885973A CN106630931B CN 106630931 B CN106630931 B CN 106630931B CN 201610885973 A CN201610885973 A CN 201610885973A CN 106630931 B CN106630931 B CN 106630931B
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- 239000000463 material Substances 0.000 title claims abstract description 55
- 239000004964 aerogel Substances 0.000 title claims abstract description 49
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 229910052681 coesite Inorganic materials 0.000 title claims abstract description 40
- 229910052906 cristobalite Inorganic materials 0.000 title claims abstract description 40
- 239000000377 silicon dioxide Substances 0.000 title claims abstract description 40
- 229910052682 stishovite Inorganic materials 0.000 title claims abstract description 40
- 229910052905 tridymite Inorganic materials 0.000 title claims abstract description 40
- 238000002360 preparation method Methods 0.000 title claims description 14
- 239000000835 fiber Substances 0.000 claims abstract description 47
- 230000002787 reinforcement Effects 0.000 claims abstract description 26
- 238000002156 mixing Methods 0.000 claims abstract description 22
- 239000000843 powder Substances 0.000 claims abstract description 22
- 239000002131 composite material Substances 0.000 claims abstract description 18
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000010703 silicon Substances 0.000 claims abstract description 16
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 16
- 238000000352 supercritical drying Methods 0.000 claims abstract description 12
- 230000032683 aging Effects 0.000 claims abstract description 11
- 239000000919 ceramic Substances 0.000 claims abstract description 5
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 49
- 238000003756 stirring Methods 0.000 claims description 39
- 238000010438 heat treatment Methods 0.000 claims description 25
- 235000019441 ethanol Nutrition 0.000 claims description 23
- 238000009413 insulation Methods 0.000 claims description 21
- 239000000203 mixture Substances 0.000 claims description 21
- 238000006243 chemical reaction Methods 0.000 claims description 14
- 238000001035 drying Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000011240 wet gel Substances 0.000 claims description 10
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 9
- SWCIQHXIXUMHKA-UHFFFAOYSA-N aluminum;trinitrate;nonahydrate Chemical compound O.O.O.O.O.O.O.O.O.[Al+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O SWCIQHXIXUMHKA-UHFFFAOYSA-N 0.000 claims description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 8
- 238000006073 displacement reaction Methods 0.000 claims description 8
- 239000000499 gel Substances 0.000 claims description 8
- 238000012545 processing Methods 0.000 claims description 7
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 6
- JGDITNMASUZKPW-UHFFFAOYSA-K aluminium trichloride hexahydrate Chemical compound O.O.O.O.O.O.Cl[Al](Cl)Cl JGDITNMASUZKPW-UHFFFAOYSA-K 0.000 claims description 6
- 150000002924 oxiranes Chemical class 0.000 claims description 6
- 239000010453 quartz Substances 0.000 claims description 6
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 5
- 239000004593 Epoxy Substances 0.000 claims description 4
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 4
- AMQJEAYHLZJPGS-UHFFFAOYSA-N N-Pentanol Chemical compound CCCCCO AMQJEAYHLZJPGS-UHFFFAOYSA-N 0.000 claims description 4
- 238000010943 off-gassing Methods 0.000 claims description 4
- 150000002921 oxetanes Chemical class 0.000 claims description 4
- LFQCEHFDDXELDD-UHFFFAOYSA-N tetramethyl orthosilicate Chemical compound CO[Si](OC)(OC)OC LFQCEHFDDXELDD-UHFFFAOYSA-N 0.000 claims description 4
- CPUDPFPXCZDNGI-UHFFFAOYSA-N triethoxy(methyl)silane Chemical compound CCO[Si](C)(OCC)OCC CPUDPFPXCZDNGI-UHFFFAOYSA-N 0.000 claims description 4
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims description 3
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 claims description 3
- 229910052863 mullite Inorganic materials 0.000 claims description 3
- 229910052984 zinc sulfide Inorganic materials 0.000 claims description 3
- PQXKWPLDPFFDJP-ZXZARUISSA-N (2r,3s)-2,3-dimethyloxirane Chemical compound C[C@H]1O[C@H]1C PQXKWPLDPFFDJP-ZXZARUISSA-N 0.000 claims description 2
- 229910003564 SiAlON Inorganic materials 0.000 claims description 2
- 239000004411 aluminium Substances 0.000 claims description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 2
- 235000011194 food seasoning agent Nutrition 0.000 claims description 2
- 229910052950 sphalerite Inorganic materials 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- DENFJSAFJTVPJR-UHFFFAOYSA-N triethoxy(ethyl)silane Chemical compound CCO[Si](CC)(OCC)OCC DENFJSAFJTVPJR-UHFFFAOYSA-N 0.000 claims description 2
- 235000012239 silicon dioxide Nutrition 0.000 claims 2
- 150000001335 aliphatic alkanes Chemical class 0.000 claims 1
- 150000002148 esters Chemical class 0.000 claims 1
- 229910052573 porcelain Inorganic materials 0.000 claims 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 10
- 238000001354 calcination Methods 0.000 abstract description 6
- 230000008901 benefit Effects 0.000 abstract description 5
- 230000008569 process Effects 0.000 abstract description 5
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 239000000654 additive Substances 0.000 abstract 1
- 230000000996 additive effect Effects 0.000 abstract 1
- 239000000701 coagulant Substances 0.000 abstract 1
- 150000002118 epoxides Chemical class 0.000 abstract 1
- 238000006460 hydrolysis reaction Methods 0.000 abstract 1
- 239000002243 precursor Substances 0.000 abstract 1
- 238000012512 characterization method Methods 0.000 description 6
- 239000008240 homogeneous mixture Substances 0.000 description 6
- 229910052580 B4C Inorganic materials 0.000 description 4
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 230000008859 change Effects 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 description 3
- INAHAJYZKVIDIZ-UHFFFAOYSA-N boron carbide Chemical compound B12B3B4C32B41 INAHAJYZKVIDIZ-UHFFFAOYSA-N 0.000 description 3
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 239000005083 Zinc sulfide Substances 0.000 description 2
- 235000013844 butane Nutrition 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical class CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 2
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- DRDVZXDWVBGGMH-UHFFFAOYSA-N zinc;sulfide Chemical compound [S-2].[Zn+2] DRDVZXDWVBGGMH-UHFFFAOYSA-N 0.000 description 2
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 description 1
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 241000790917 Dioxys <bee> Species 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229910003978 SiClx Inorganic materials 0.000 description 1
- ILRRQNADMUWWFW-UHFFFAOYSA-K aluminium phosphate Chemical compound O1[Al]2OP1(=O)O2 ILRRQNADMUWWFW-UHFFFAOYSA-K 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- BFAKENXZKHGIGE-UHFFFAOYSA-N bis(2,3,5,6-tetrafluoro-4-iodophenyl)diazene Chemical compound FC1=C(C(=C(C(=C1F)I)F)F)N=NC1=C(C(=C(C(=C1F)F)I)F)F BFAKENXZKHGIGE-UHFFFAOYSA-N 0.000 description 1
- 229910001593 boehmite Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 230000009970 fire resistant effect Effects 0.000 description 1
- FAHBNUUHRFUEAI-UHFFFAOYSA-M hydroxidooxidoaluminium Chemical compound O[Al]=O FAHBNUUHRFUEAI-UHFFFAOYSA-M 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011490 mineral wool Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000009738 saturating Methods 0.000 description 1
- -1 silicane alkane Chemical class 0.000 description 1
- 238000003980 solgel method Methods 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
-
- 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
- C04B30/02—Compositions for artificial stone, not containing binders containing fibrous materials
-
- 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
- C04B2201/20—Mortars, concrete or artificial stone characterised by specific physical values for the density
-
- 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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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Fibers (AREA)
Abstract
The invention relates to a wave-transparent heat-insulating integrated fiber-reinforced Al2O3‑SiO2Methods of making aerogel materials. Mixing a silicon source and an aluminum source, performing hydrolysis reaction, then taking epoxide as a coagulant, taking functional powder with excellent wave-transmitting performance as an additive and inorganic high-temperature-resistant ceramic fiber as a reinforcement, performing sol-gel, aging and supercritical drying to obtain precursor composite aerogel, and then performing air thermal calcination in a muffle furnace to finally prepare the wave-transmitting and heat-insulating integrated fiber-reinforced Al2O3‑SiO2An aerogel material. The invention has the advantages of simple material and simple process, and the process is simple to operate and easy to realize mass production.
Description
Technical field
The invention belongs to the preparation process fields of aerogel material, are related to a kind of wave transparent heat-insulation integrative fiber reinforcement
Al2O3-SiO2The preparation method of aerogel material.
Background technique
Air weapon plays great function in modern war, have become influence war win and defeat it is crucial because
Element.In particular with the continuous improvement of the hypersonic aircrafts flying speed such as guided missile, the height as caused by Aerodynamic Heating warms ring
Border problem becomes more severe.When speed flight of the hypersonic aircraft with 4~5 Mach, cabin hull-skin temperature is reachable
400~600 DEG C, but successively with the hypersonic aircrafts such as X-15, X-20, X-30, X-37B, X-43 and sky and space plane
It comes out, the flying speed of these aircraft will be up to 8 Mach or more, reenters process up to 10 minutes or so, flies so as to cause it
The visual field open area temperature that machine head, leading edge of a wing etc. are adapted to fit antenna house may be up to 1200 DEG C, these positions certainly will will be met
To harsh Aerodynamic Heating problem, to prevent outside heat from being passed to internal body by wave transparent window or cover, and do not influence to fly
The requirement of row device normal communication, there is an urgent need to prepare a kind of novel fire resistant, lightweight, lower thermal conductivity, high wave transparent effectively insulating material
Material.Aerogel composite has low-density, high porosity, low as a kind of novel light, efficient nano porous heat insulation material
The advantages that thermal conductivity, low-k.Compared with traditional heat-barrier material, heat insulation is more superior, and has good
Wave performance, high temperature resistance and damping effect, wherein Al2O3-SiO2Aeroge is with respect to SiO2For aeroge, have more excellent
Different heat resistance, effective use when can be long under 1200 DEG C of aerobic environment.Therefore the lightweight heat-proof wave transparent that this project is carried out
Integrated A l2O3-SiO2The research of aerogel composite can establish material and technology basis for its engineering application, have
It hopes and is applied to reuse aircraft antenna house or window, for safeguarding national security with great social benefit.
Summary of the invention
A kind of wave transparent heat-insulation integrative is provided the purpose of the invention is to improve the shortcomings of the prior art
Fiber reinforcement Al2O3-SiO2The preparation method of aerogel material.This method materials and simple process, microstructure controllability is good,
The aerogel material prepared has the characteristics such as high temperature resistant, low-density, lower thermal conductivity, low-k, low dielectric loss, to
Reach the size and weight for significantly reducing radome, improve the heat insulation of radar and the effect of wave transparent performance, thus full
Wave transparent heat-insulated one in the weaponrys radome such as the hypersonic Reusable launch vehicles of foot, air defense, latent ground, cruise missile
The urgent need of body material.
The technical solution of the present invention is as follows: a kind of wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2The system of aerogel material
Preparation Method, the specific steps of which are as follows:
(1) after evenly mixing by silicon source, ethyl alcohol, water, silicon source, in 20~50 DEG C of at a temperature of uniform stirring;
(2) high-performance wave transparent powder is added in sol system obtained in step (1), is continued at 20~50 DEG C
At a temperature of uniform stirring, obtain the mixture with wave transparent powder;
(3) epoxides is added in the mixture, continues to pour into the mixture after stirring that be equipped with inorganic high-temperature resistant saturating
Reaction places 10~30h to gel in the mold of wave ceramic fibre;
(4) Ageing solution is added, carries out replacing to obtain wet gel in 25~75 DEG C of baking oven;
(5) wet gel obtained in step (4) is subjected to supercritical drying processing, obtains fiber reinforcement AlOOH-SiO2
Aerogel composite;
(6) composite aerogel obtained in step (5) is subjected to air heat treatment in Muffle furnace, thus obtain wave transparent every
Heating integrated fiber reinforcement Al2O3-SiO2Aerogel material;
Wherein: the silicon source, ethyl alcohol, water, silicon source in step (1) are according to 1:(5~30): (10~60): (0.128~1)
Molar ratio uniformly mixes;The reasonable opinion conversion Al of the quality of wave transparent powder in step (2)2O3-SiO2The quality of aerogel material
20%~80%;The molar ratio of epoxides and silicon source is (4~10) in step (3): 1.
Silicon source described in preferred steps (1) is one of Aluminium chloride hexahydrate or ANN aluminium nitrate nonahydrate or its mixing
Object.
Silicon source described in preferred steps (2) is tetraethyl orthosilicate, methyl orthosilicate, methyltriethoxysilane, first
Or mixtures thereof one of ethyl triethoxy silicane alkane or ethyl triethoxysilane.
It is Si that wave transparent described in preferred steps (2), which has excellent performance powder,3N4、B4C, BN, β-SiAlON, ZnS or AlPO4
One of or mixture.
Mixing speed is 400~600rpm in preferred steps (1), and mixing time is 0.5~4h;Stirring speed in step (2)
Degree is 400~600rpm, and mixing time is 0.1~2h;Mixing speed is 400~600rpm in step (3), and mixing time is
0.5~2h.
Epoxides described in preferred steps (3) is propylene oxide, cis- -2,3 epoxy butane, oxetanes or ring
Or mixtures thereof one of oxygen propyl alcohol.
High temperature resistant wave-permeable ceramic fibre described in preferred steps (3) be polycrystalline alumina fiber, polycrystalline mullite fibre,
One of high purity quartz fiber or alumina silicate fibre.
Displacement number is 3~6 times in preferred steps (4), each time is 12~for 24 hours;Ageing solution described in step (4)
For or mixtures thereof one of ethyl alcohol, methanol, acetone, ether, n-amyl alcohol or isopropanol.
Supercritical drying drying method described in preferred steps (5) is ethyl alcohol or CO 2 supercritical seasoning: ethyl alcohol is super
When critical dry, temperature is 250~280 DEG C, and pressure is 8~15MPa in autoclave, and drying time is 2~8h;Titanium dioxide
When carbon supercritical drying, temperature is 50~70 DEG C, and pressure is 8~12MPa in autoclave, and outgassing rate is 5~20L/
Min, drying time are 8~20h.
Air heat treatment temperature described in preferred steps (6) is between 450~800 DEG C;Heating rate be 2-5 DEG C/
Min, heat treatment time are 2~5h.
The utility model has the advantages that
The method of the present invention and a kind of wave transparent heat-insulation integrative fiber reinforcement Al prepared by this method2O3-SiO2Aeroge
Material has a characteristic that
(1) simple process.Using a step sol-gel method, while silicon source and silicon source are introduced, and by the way that wave transparent performance is added
Excellent function powder and inorganic high-temperature resistant wave transparent ceramic fibre, it is final to make without introducing any dispersing agent or surfactant
Obtain wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2Aerogel material is suitble to industrial mass production.
(2) material prepared has the features such as lightweight, high temperature resistant, low-density, lower thermal conductivity, high wave transmission rate, can be its work
Material and technology basis are established in journey application, are expected to be applied to reuse aircraft antenna house or window, for ensureing
National security has great social benefit.
Detailed description of the invention
Fig. 1 is the pure Al of wave transparent heat-insulation integrative obtained in example 12O3-SiO2Aerogel material and wave transparent heat-insulation integrative
Fiber reinforcement Al2O3-SiO2Aerogel material material object photo;Wherein a is the pure Al of wave transparent heat-insulation integrative2O3-SiO2Airsetting glue material
Material, b are wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2Aerogel material;Fig. 2 is wave transparent heat-insulated one obtained in example 2
Body silicon nitride adulterates Al2O3-SiO2The SEM of aerogel material schemes;
Fig. 3 is wave transparent heat-insulation integrative high purity quartz fiber reinforcement Al obtained in example 32O3-SiO2Aerogel material
Dielectric constant and dielectric loss are with test frequency change curve;Wherein above one be dielectric constant, below one for medium damage
Consumption.
Specific embodiment
Example 1
After evenly mixing according to molar ratio 1:5:60:0.128 by Aluminium chloride hexahydrate, ethyl alcohol, water, tetraethyl orthosilicate,
Uniform stirring 2h under being 500rpm in 50 DEG C of temperature, stirring rate.Then the alpha-silicon nitride powders 50% wave transparent being had excellent performance
Be added in above-mentioned sol system, continue 50 DEG C temperature, stirring rate be 500rpm under uniform stirring 2h, obtain with nitrogen
The homogeneous mixture of SiClx powder.According to being that propylene oxide is added in 8:1 with the molar ratio of Aluminium chloride hexahydrate, stirring rate is
The mixture is poured into reaction in the mold for being equipped with high purity quartz fiber after stirring 0.5h under 500rpm and places 30h to gel
Ethyl alcohol Ageing solution is added afterwards, displacement 3 times, each 12h are carried out in 50 DEG C of baking oven.Then wet gel progress ethyl alcohol is surpassed and is faced
Boundary is dried, and reaction temperature is 250 DEG C, and pressure is 10MPa in autoclave, and drying time 2h obtains fiber reinforcement
AlOOH-SiO2Aerogel material.Finally obtained composite aerogel is heat-treated in Muffle furnace, calcination temperature is 600
DEG C, heating rate 2, DEG C/min, heat treatment time 2h, to obtain wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2
Aerogel material.Characterization discovery after tested, the apparent density of the composite material are 0.22g/cm3, room temperature thermal conductivity is
0.030W·m-1K-1, dielectric constant 1.3, dielectric loss 0.003.The obtained pure Al of wave transparent heat-insulation integrative2O3-SiO2
Aerogel material and wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2Aerogel material material object photo is from shown in Fig. 1, Cong Tuzhong
As can be seen that the function powder due to doping is jade-green silicon nitride micro materials, pure aerogel material obtained is in
Existing jade-green appearance, while silicon nitride is uniformly dispersed inside aeroge.And fibre-reinforced material surface is bright and clean smooth, it can
Processability is strong.
Example 2
After evenly mixing according to molar ratio 1:10:30:0.5 by ANN aluminium nitrate nonahydrate, ethyl alcohol, water, methyl orthosilicate, exist
Uniform stirring 0.5h at a temperature of 25 DEG C.Then the boron carbide powder that 30% wave transparent is had excellent performance is added to above-mentioned sol system
In, continue the at a temperature of uniform stirring 0.5h at 25 DEG C, obtains the homogeneous mixture with boron carbide powder.It is hydrated according to nine
The molar ratio of aluminum nitrate be 5:1 be added cis- -2,3 epoxy butanes, stir 1h after the mixture is poured into be equipped with polycrystalline not come
Reaction is added ethyl alcohol Ageing solution after placing 20h, displacement 5 times is carried out in 45 DEG C of baking oven, often to gel in the mold of mineral wool
Secondary 18h.Then the wet gel is subjected to ethanol supercritical drying processing, reaction temperature is 270 DEG C, and pressure is in autoclave
14MPa, drying time 4h obtain fiber reinforcement AlOOH-SiO2Aerogel material.Finally obtained composite aerogel is existed
It is heat-treated in Muffle furnace, calcination temperature is at 500 DEG C, and heating rate is 3 DEG C/min, heat treatment time 3h, to obtain
Wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2Aerogel material.Characterization discovery after tested, the apparent density of the composite material
For 0.18g/cm3, room temperature thermal conductivity is 0.035Wm-1K-1, dielectric constant 1.6, dielectric loss 0.008.Obtained
The pure Al of wave transparent heat-insulation integrative2O3-SiO2The SEM of aerogel material schemes as shown in Fig. 2, it may be seen that the material from figure
Interior porosity is high, while acicular boehmite is mutually intertwined with the structure as pearl chain, and structure is uniform.
Example 3
ANN aluminium nitrate nonahydrate, ethyl alcohol, water, methyltriethoxysilane are uniformly mixed according to molar ratio 1:25:40:0.75
Afterwards, 40 DEG C temperature, stirring rate be 550rpm under uniform stirring 1h.Then the boron nitride powder 80% wave transparent being had excellent performance
End is added in above-mentioned sol system, continue 40 DEG C temperature, stirring rate be 550rpm under uniform stirring 1h, had
The homogeneous mixture of boron nitride powder.According to being that oxetanes is added in 6:1 with the molar ratio of ANN aluminium nitrate nonahydrate, in stirring speed
Rate is that the mixture is poured into reaction in the mold for be equipped with alumina silicate fibre to place 15h to gel after stirring 2h under 400rpm
Ethyl alcohol Ageing solution is added afterwards, displacement 3 times, each 12h are carried out in 70 DEG C of baking oven.Then the wet gel is subjected to carbon dioxide
Supercritical drying processing, reaction temperature are 70 DEG C, and pressure is 12MPa, outgassing rate 5L/min, drying in autoclave
Time is 20h, obtains fiber reinforcement AlOOH-SiO2Aerogel material.Finally by obtained composite aerogel in Muffle furnace into
Row heat treatment, calcination temperature is at 450 DEG C, and heating rate is 4 DEG C/min, heat treatment time 3h, to obtain wave transparent heat-insulated one
Body chemical fibre ties up REINFORCED Al2O3-SiO2Aerogel material.Characterization discovery after tested, the apparent density of the composite material are 0.25g/
cm3, room temperature thermal conductivity is 0.028 Wm-1K-1, dielectric constant 1.5, dielectric loss 0.006.Obtained wave transparent is heat-insulated
Integrated high purity quartz fiber reinforcement Al2O3-SiO2The dielectric constant and dielectric loss of aerogel material change bent with test frequency
Line is as shown in figure 3, from the figure, it can be seen that with frequency by 7201MHz to 16474MHz range, dielectric constant is maintained essentially in
1.5 hereinafter, and dielectric loss substantially 0.004 or so, therefore material has very low dielectric constant and dielectric loss, wave
It can be excellent.
Example 4
After evenly mixing according to molar ratio 1:30:60:0.8 by Aluminium chloride hexahydrate, ethyl alcohol, water, tetraethyl orthosilicate, exist
40 DEG C of temperature, stirring rate are uniform stirring 0.5h under 600rpm.Then the zinc sulfide powder 60% wave transparent being had excellent performance
Be added in above-mentioned sol system, continue 40 DEG C temperature, stirring rate be 600rpm under uniform stirring 0.1h, had
There is the homogeneous mixture of zinc sulphide powder.According to being that oxetanes is added in 6:1 with the molar ratio of Aluminium chloride hexahydrate, stirring
Rate is to stir after forty minutes to pour into the mixture in the mold for being equipped with high purity quartz fiber under 600rpm to react to gel,
Ether Ageing solution is added after placing 20h, displacement 6 times, each 12h are carried out in 30 DEG C of baking oven.Then the wet gel is carried out
Ethanol supercritical drying processing, reaction temperature are 260 DEG C, and pressure is 8MPa in autoclave, and drying time 6h obtains fibre
Tie up REINFORCED Al OOH-SiO2Aerogel material.Finally obtained composite aerogel is heat-treated in Muffle furnace, calcining temperature
Degree is at 500 DEG C, and heating rate is 5 DEG C/min, heat treatment time 5h, to obtain wave transparent heat-insulation integrative fiber reinforcement
Al2O3-SiO2Aerogel material.Characterization discovery after tested, the apparent density of the composite material are 0.17g/cm3, room temperature thermal conductivity
For 0.026Wm-1K-1, dielectric constant 1.4, dielectric loss 0.007.
Example 5
After evenly mixing according to molar ratio 1:20:30:0.9 by ANN aluminium nitrate nonahydrate, ethyl alcohol, water, tetraethyl orthosilicate, exist
30 DEG C of temperature, stirring rate are uniform stirring 4h under 400rpm.Then the Aluminum phosphate powders that 20% wave transparent is had excellent performance are added
Enter into above-mentioned sol system, continue 30 DEG C temperature, stirring rate be 400rpm under uniform stirring 2h, obtain with phosphorus
The homogeneous mixture of sour aluminium powder body.According to being that propylene oxide is added in 4:1 with the molar ratio of ANN aluminium nitrate nonahydrate, stirring rate is
The mixture is poured into reaction in the mold for be equipped with polycrystalline alumina fiber to place to gel after stirring 1.2h under 500rpm
Acetone Ageing solution is added after 20h, displacement 3 times is carried out in 75 DEG C of baking oven, every time for 24 hours.Then the wet gel is subjected to dioxy
Change carbon supercritical drying processing, reaction temperature be 50 DEG C, in autoclave pressure be 8MPa, outgassing rate 20L/min,
Drying time is 8h, obtains fiber reinforcement AlOOH-SiO2Aerogel material.Finally by obtained composite aerogel in Muffle furnace
In be heat-treated, for calcination temperature at 800 DEG C, heating rate is 5 DEG C/min, heat treatment time 5h, thus obtain wave transparent every
Heating integrated fiber reinforcement Al2O3-SiO2Aerogel material.Characterization discovery, the apparent density of the composite material are after tested
0.28g/cm3, room temperature thermal conductivity is 0.032 Wm-1K-1, dielectric constant 1.7, dielectric loss 0.009.
Example 6
After evenly mixing according to molar ratio 1:10:10:1 by ANN aluminium nitrate nonahydrate, ethyl alcohol, water, methyl orthosilicate, at 25 DEG C
Temperature, stirring rate be 500rpm under uniform stirring 0.5h.Then the boron carbide powder 80% wave transparent being had excellent performance is added
Into above-mentioned sol system, continue 25 DEG C temperature, stirring rate be 500rpm under uniform stirring 0.5h, obtain with carbon
Change the homogeneous mixture of boron powder.According to being that 5:1 is added cis- -2 with the molar ratio of ANN aluminium nitrate nonahydrate, 3 epoxy butanes are being stirred
Mixing rate is to pour into the mixture in the mold for be equipped with polycrystalline mullite fibre to react to solidifying after stirring 1.4h under 500rpm
Glue is added Methanol aging liquid after placing 20h, displacement 5 times, each 18h is carried out in 45 DEG C of baking oven.Then by the wet gel into
The processing of row ethanol supercritical drying, reaction temperature are 280 DEG C, and pressure is 15MPa in autoclave, and drying time 8h is obtained
To fiber reinforcement AlOOH-SiO2Aerogel material.Obtained composite aerogel is heat-treated in Muffle furnace finally, is forged
Temperature is burnt at 500 DEG C, and heating rate is 3 DEG C/min, heat treatment time 5h, to obtain wave transparent heat-insulation integrative fiber reinforcement
Al2O3-SiO2Aerogel material.Characterization discovery after tested, the apparent density of the composite material are 0.19g/cm3, room temperature thermal conductivity
For 0.040Wm-1K-1, dielectric constant 1.4, dielectric loss 0.009.
Claims (8)
1. a kind of wave transparent heat-insulation integrative fiber reinforcement Al2O3-SiO2The preparation method of aerogel material, the specific steps of which are as follows:
(1) after evenly mixing by silicon source, ethyl alcohol, water, silicon source, in 20~50 DEG C of at a temperature of uniform stirring;The wherein aluminium
Source is or mixtures thereof one of Aluminium chloride hexahydrate or ANN aluminium nitrate nonahydrate;
(2) high-performance wave transparent powder is added in sol system obtained in step (1), continue 20~50 DEG C at a temperature of
Uniform stirring obtains the mixture with wave transparent powder;Wherein the high-performance wave transparent powder is Si3N4、B4C、BN、β-
SiAlON, ZnS or AlPO4One of or mixture;Wherein mixing speed be 400~600rpm, mixing time be 0.1~
2h;
(3) epoxides is added in the mixture, continue stirring after the mixture is poured into be equipped with inorganic high-temperature resistant wave transparent pottery
Reaction places 10~30h to gel in the mold of porcelain fiber;Wherein mixing speed is 400~600rpm, mixing time 0.5
~2h;
(4) Ageing solution is added, carries out replacing to obtain wet gel in 25~75 DEG C of baking oven;
(5) wet gel obtained in step (4) is subjected to supercritical drying processing, obtains fiber reinforcement AlOOH-SiO2Compound gas
Gel rubber material;
(6) composite aerogel obtained in step (5) is subjected to air heat treatment in Muffle furnace, to obtain wave transparent heat-insulated one
Body chemical fibre ties up REINFORCED Al2O3-SiO2Aerogel material;
Wherein: the silicon source, ethyl alcohol, water, silicon source in step (1) are according to 1:(5~30): (10~60): mole of (0.128~1)
Than uniformly mixing;The reasonable opinion conversion Al of the quality of wave transparent powder in step (2)2O3-SiO2The 20% of the quality of aerogel material
~80%;The molar ratio of epoxides and silicon source is (4~10) in step (3): 1.
2. preparation method according to claim 1, it is characterised in that silicon source described in step (1) is positive silicic acid tetrem
One of ester, methyl orthosilicate, methyltriethoxysilane, methyltriethoxysilane or ethyl triethoxysilane or its
Mixture.
3. preparation method according to claim 1, it is characterised in that mixing speed is 400~600rpm in step (1), is stirred
Mixing the time is 0.5~4h.
4. preparation method according to claim 1, it is characterised in that epoxides described in step (3) is epoxy third
Or mixtures thereof one of alkane, cis- -2,3 epoxy butane, oxetanes or epoxy prapanol.
5. preparation method according to claim 1, it is characterised in that high temperature resistant wave-permeable ceramic fibre described in step (3)
For one of polycrystalline alumina fiber, polycrystalline mullite fibre, high purity quartz fiber or alumina silicate fibre.
6. preparation method according to claim 1, it is characterised in that displacement number is 3~6 times, when each in step (4)
Between for 12~for 24 hours;Ageing solution described in step (4) is one of ethyl alcohol, methanol, acetone, ether, n-amyl alcohol or isopropanol
Or mixtures thereof.
7. preparation method according to claim 1, it is characterised in that supercritical drying drying method described in step (5) is second
Alcohol or CO 2 supercritical seasoning: when ethanol supercritical drying, temperature is 250~280 DEG C, and pressure is in autoclave
8~15MPa, drying time are 2~8h;When CO 2 supercritical is dry, temperature is 50~70 DEG C, pressure in autoclave
For 8~12MPa, outgassing rate is 5~20L/min, and drying time is 8~20h.
8. preparation method according to claim 1, it is characterised in that air heat treatment temperature described in step (6) exists
Between 450~800 DEG C;Heating rate is 2-5 DEG C/min, and heat treatment time is 2~5h.
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CN107185463B (en) * | 2017-06-26 | 2019-10-18 | 浙江工业大学 | A kind of SiO2-Al2O3The synthetic method of mixed oxide aerogel material |
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102531521A (en) * | 2012-02-21 | 2012-07-04 | 湖北三江航天江北机械工程有限公司 | Method for preparing wave-transmission SiO2 aerogel heat-insulation composite material by using normal-pressure drying equipment |
CN103274697A (en) * | 2013-06-04 | 2013-09-04 | 哈尔滨工业大学 | Method for preparing thermal insulation wave-transparent SiO2-Si3N4 composite material |
CN104844149A (en) * | 2015-05-27 | 2015-08-19 | 南京工业大学 | Mullite fiber felt reinforced SiO2-Al2O3Preparation method of aerogel composite heat-insulating material |
-
2016
- 2016-10-10 CN CN201610885973.7A patent/CN106630931B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102531521A (en) * | 2012-02-21 | 2012-07-04 | 湖北三江航天江北机械工程有限公司 | Method for preparing wave-transmission SiO2 aerogel heat-insulation composite material by using normal-pressure drying equipment |
CN103274697A (en) * | 2013-06-04 | 2013-09-04 | 哈尔滨工业大学 | Method for preparing thermal insulation wave-transparent SiO2-Si3N4 composite material |
CN104844149A (en) * | 2015-05-27 | 2015-08-19 | 南京工业大学 | Mullite fiber felt reinforced SiO2-Al2O3Preparation method of aerogel composite heat-insulating material |
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