WO1992020623A1 - Process for the preparation of a silica aerogel-like material - Google Patents

Process for the preparation of a silica aerogel-like material Download PDF

Info

Publication number
WO1992020623A1
WO1992020623A1 PCT/NO1992/000096 NO9200096W WO9220623A1 WO 1992020623 A1 WO1992020623 A1 WO 1992020623A1 NO 9200096 W NO9200096 W NO 9200096W WO 9220623 A1 WO9220623 A1 WO 9220623A1
Authority
WO
WIPO (PCT)
Prior art keywords
alcogel
contact
silica
solution
drying
Prior art date
Application number
PCT/NO1992/000096
Other languages
French (fr)
Inventor
Mari-Ann Einarsrud
Siv Haereid
Original Assignee
Sinvent A/S
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sinvent A/S filed Critical Sinvent A/S
Priority to AU17852/92A priority Critical patent/AU662147C/en
Priority to BR9206051A priority patent/BR9206051A/en
Priority to CA002109715A priority patent/CA2109715A1/en
Priority to EP92910393A priority patent/EP0646097A1/en
Priority to JP4510552A priority patent/JPH06510268A/en
Publication of WO1992020623A1 publication Critical patent/WO1992020623A1/en
Priority to FI935203A priority patent/FI935203A/en
Priority to NO934233A priority patent/NO934233D0/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00Silicon; Compounds thereof
    • C01B33/113Silicon oxides; Hydrates thereof
    • C01B33/12Silica; Hydrates thereof, e.g. lepidoic silicic acid
    • C01B33/16Preparation of silica xerogels
    • C01B33/163Preparation of silica xerogels by hydrolysis of organosilicon compounds, e.g. ethyl orthosilicate

Definitions

  • This invention relates to a process for the preparation of a material similar to silica aerogel.
  • Silica aerogel is a porous material of a very low density and it contains up to 99% of air.
  • the type of silica aerogel prepared according to the present invention is normally called silica xerogel. Due its high porosity, the material has excellent heat insulating properties, and since the pore size of the material is smaller than the wave length of visible light, it is also transparent.
  • Typical properties of silica aerogel are as follows:
  • Pore size 10 - 20 nm
  • Silica aerogel has an insulating property which is approximately twice as good as that of rockwool, and since it is also transparent, it may be used as insulation in windows.
  • silica xerogel/aerogel Due to its porosity silica xerogel/aerogel has also a very high capacity for sucking up liquid and may also be used as starting material for composite materials and carrier for catalyst and liquids, e.g. electrolytes.
  • TMOS tetramethoxysilane
  • the alcogel formation takes place by a direct acid- and/or base-catalysed hydrolysis of TMOS in a so-called sol-gel technology.
  • the alcogel formed is a silica skeleton surrounded by aqeous methanol.
  • the problem which then arises is to remove the aqueous methanol from the silica skeleton to obtain the- aerogel.
  • silica xerogel will have a relatively high density, e.g. about 1,4 g/cm 3 .
  • preparation method a) will result in 10 an aerogel.
  • b> and c) there will be obtained a gel which may be described as silica cryogel and silica xerogel respectively, which may have approximately the same properties as silica aerogel.
  • Drying method b) is cheap, but due to volume expansion of the solvent during crystallisation (i.e. freezing) , the result may easily be cracking of the gel during the drying.
  • Drying method c) normally takes place with a large shrinkage of the gel due to a collapse of the gel structure.
  • the purpose of the present invention is to provide a process for preparing silica xerogel (aerogel) having a relatively low density (i.e. below 0.5 g/cm 3 ) and such that the material is suitable as a heat insulating material.
  • the process is characterised by the fact that the alcogel formed is contacted with a solution of a tetraalkoxysilane. The contact is maintained at or above room temperature to stabilise the silica skeleton, whereafter the alcogel is slowly dryed at or above room temperature and at above approximately atmospheric pressure.
  • the alcogel Before the alcogel is contacted with the solution of tetraalkoxysilane it may be suitable to contact the alcogel with a liquid to wash the gel (in order to change the composition of the aqueous alcohol surrounding the silica skeleton) and to replace functional groups on the surface.
  • This liquid may e.g. consist of a mixture of water and alcohol, preferably about 40% methanol. This liquid may also be replaced several times.
  • the liquid added for washing may have a temperature up to the boiling point, preferably room temperature.
  • tetrametoxysilane is used for preparing the alcogel, whereafter the gel formed is contacted with a solution of tetraethoxysilane, e.g. in a lower alcohol, particularly methanol.
  • the contact between the alcogel and the later added teraalkoxysilane is suitably maintained for a sufficiently long time for a strengthening of the gel network to take place, e.g. from 6 hours to 16 days, at a temperature which does not represent any risk for the alcogel, preferably from 20 to 200°C, particularly 40-80°C.
  • An increased ageing time results in the largest pores in the product, i.e the lowest density.
  • the washing of the alcogel with liquid, e.g aqueous alcohol results in less shrinking of the gel and larger pores.
  • the alcohol used is normally a mono-,, di- or trihydric alkanol, particularly with 1-10 C-atoms, preferably methanol. 5
  • Controlled drying may be accomplished by allowing it to take place in an atmosphere which contains components
  • the drying may e.g. take place in a chamber with such an atmosphere, or it may take place while the alcogel is kept almost completely covered, e.g. up to 99%, whereby the
  • the drying is suitably carried out at a temperature in the range 40 - 200°C.
  • the drying temperature may also be gradually varied from room temperature to the boiling point of aqueous alcohol.
  • the thereby formed xerogel has a low density (e.g. 0,5 g/cm 3 or lower) and has also a homogeneous structure.
  • Example 1 An alcogel was prepared by hydrolysis and polycondensation of
  • TEOS tetraethoxysilane
  • the mould was " removed from the bath after approximately 24 « hours, and the bath was then kept covered for additional 24
  • the surface area of the xerogel is in the range 600 - 650 m 2 /g.
  • the thermal conductivity of the silica xeroge? material formed has been measured down to 0.02 ⁇ 0.004 W. mK at 450C.
  • Example 2 An alcogel was prepared as described in Example 1. After up to several hours of standing in covered condition the mouled with the alcogel was immersed in liquid consisting of methanol and water (e.g. 30 volume % of water) . The liquid mixture was changed three times with 24 hours intervals. The alcogel in the liquid mixtures was kept at room temperature during the entire washing. After four days the washing solution was replaced by a solution of tetraethoxysilane as in Example l. The rest is as in Example 1.
  • the treatment of the alcogel in the solution of water and methanol causes less shrinkage of the alcogel during drying.
  • the shrinkage of the alcogel during drying is about 13%.
  • the thermal conductivity of the silica xerogel prepared has been measured down to 0.028 ⁇ 0.04W/mK.

Abstract

A process for the preparation of silica xerogel by hydrolysis and polycondensation of a tetraalkoxysilane to form an alcogel which is a silica skeleton surrounded by an aqueous methanol, whereafter the aqueous methanol is removed by evaporation. The alcogel formed is brought in contact with a solution of tetraalkoxysilane, the contact is maintained at or above room temperature to strengthen the silica skeleton, whereafter the gel is dried slowly at or above room temperature and at about atmospheric pressure. Before the alcogel is brought in contact with the solution of tetraalkoxylsilane it may be washed with a solution (e.g. aqueous methanol) to change the composition of the aqueous alcohol surrounding the silica skeleton or to change the functional groups on the surface of the alcogel.

Description

Process for the preparation of a silica aerogel-like material.
This invention relates to a process for the preparation of a material similar to silica aerogel. Silica aerogel is a porous material of a very low density and it contains up to 99% of air. The type of silica aerogel prepared according to the present invention is normally called silica xerogel. Due its high porosity, the material has excellent heat insulating properties, and since the pore size of the material is smaller than the wave length of visible light, it is also transparent. Typical properties of silica aerogel are as follows:
Density: 70 - 250 kg/m3
Refractive index: 1.02 - 1.05 Thermal conductivity in air: 0.021 /mK at 20°C
Thermal conductivity in vacuum: 0.008 W/mK at 20°C
Particle size: 4 - 7 nm
Pore size: 10 - 20 nm
Transmittance 88% for 10 mm thickness
Silica aerogel has an insulating property which is approximately twice as good as that of rockwool, and since it is also transparent, it may be used as insulation in windows.
Due to its porosity silica xerogel/aerogel has also a very high capacity for sucking up liquid and may also be used as starting material for composite materials and carrier for catalyst and liquids, e.g. electrolytes.
Originally, sodium silicate-hydrate was used as starting material for the preparation of silica aerogel, and in a hydrogen chloride catalysed reaction between the silicate and water an aquagel was formed. However, this preparation route is very time-consuming since the aquagel has to be washed with alcohol before the drying step may take place. The drying process is necessary to remove preferably all liguid, leaving only the desired silica network. More recently tetramethoxysilane, Si(OCH3)4, TMOS, has also been used as starting material for the preparation of silica aerogel. TMOS is a suitable starting material since it is easy to handle, easy to prepare in pure form and easy to hydrolyse. However, it is toxic and expensive. The alcogel formation takes place by a direct acid- and/or base-catalysed hydrolysis of TMOS in a so-called sol-gel technology. The alcogel formed is a silica skeleton surrounded by aqeous methanol. The problem which then arises is to remove the aqueous methanol from the silica skeleton to obtain the- aerogel.
In order to prepare the desired aerogel, it is as mentioned above, necessary to remove the liquid surrounding the silica skeleton, and this may be done by eliminating or at least reducing the capillary forces working in the alcogel when the liquid front withdraws, or the network may be stengthened so that the pores do not collapse when the liquid is removed.
Two drying procedures are possible where the capillary forces are eliminated: a) Supercritical drying where the solvent in liquid phase is transformed to the gaseous phase under elevated pressure in an autoclave at a temperature above the critical point of the solvent. A modification of this drying method is to extract the solvent with another compound such as CO2, which has lower critical point. Supercritical drying is a somewhat dangerous method because the large amounts of methanol which is expelled may lead to an explosion if there is a leak.
b) Freeze drying, where the alcogel is frozen to become solid, whereafter the solvent is subjected to sublimation under reduced pressure.
In the third possible method, viz.
c) Air drying and direct evaporation of the solvent where the liquid phase is transformed to gaseous phase, the drying process will normally lead to collapse of the pores and crack formation in the gel due to capillary forces. In the literature, the addition a DCCA (Drying Control Chemical <
Additive) to the sol has been reported, to obtain a narrow 5 pore size distribution and hence a reduction in the differential strain in the alcogel, whereby cracking is considerably reduced. However, the resulting silica xerogel will have a relatively high density, e.g. about 1,4 g/cm3. Strictly speaking, only preparation method a) will result in 10 an aerogel. In the other two methods b> and c) there will be obtained a gel which may be described as silica cryogel and silica xerogel respectively, which may have approximately the same properties as silica aerogel.
15 Drying method a) with supercritical drying results in an aerogel with low density and relatively good optical properties, but the method is expensive and dangerous due to the high pressure and the high temperature during drying. In the production of tiles for use as insulation in windows it
20 will be necessary with an autoclave which will represent a considerable element of risk during operation due to large amounts of methanol which can be ignited. By using e.g. CO2 as medium during the supercritical drying, an extraction of the solvent is necessary.
25
Drying method b) is cheap, but due to volume expansion of the solvent during crystallisation (i.e. freezing) , the result may easily be cracking of the gel during the drying.
30 Drying method c) normally takes place with a large shrinkage of the gel due to a collapse of the gel structure. In the preparation of high density glass by sintering from these xerogels which are not particularly reactive, it is
» problematic to remove organic residues, i.e. DCCA.
35
The purpose of the present invention is to provide a process for preparing silica xerogel (aerogel) having a relatively low density (i.e. below 0.5 g/cm3) and such that the material is suitable as a heat insulating material.
According to present invention there is provided a new and improved process for the preparation of silica xerogel of low density by hydrolysis and polycondensation of a tetraalkoxysilane, to form a an alcogel which is a silica skeleton surrounded by aqueous alcohol. The process is characterised by the fact that the alcogel formed is contacted with a solution of a tetraalkoxysilane. The contact is maintained at or above room temperature to stabilise the silica skeleton, whereafter the alcogel is slowly dryed at or above room temperature and at above approximately atmospheric pressure. Before the alcogel is contacted with the solution of tetraalkoxysilane it may be suitable to contact the alcogel with a liquid to wash the gel (in order to change the composition of the aqueous alcohol surrounding the silica skeleton) and to replace functional groups on the surface. This liquid may e.g. consist of a mixture of water and alcohol, preferably about 40% methanol. This liquid may also be replaced several times. The liquid added for washing may have a temperature up to the boiling point, preferably room temperature.
Suitably tetrametoxysilane is used for preparing the alcogel, whereafter the gel formed is contacted with a solution of tetraethoxysilane, e.g. in a lower alcohol, particularly methanol.
The contact between the alcogel and the later added teraalkoxysilane is suitably maintained for a sufficiently long time for a strengthening of the gel network to take place, e.g. from 6 hours to 16 days, at a temperature which does not represent any risk for the alcogel, preferably from 20 to 200°C, particularly 40-80°C. An increased ageing time results in the largest pores in the product, i.e the lowest density. The washing of the alcogel with liquid, e.g aqueous alcohol results in less shrinking of the gel and larger pores.
The alcohol used is normally a mono-,, di- or trihydric alkanol, particularly with 1-10 C-atoms, preferably methanol. 5
It is of essential importance that the drying takes place under controlled conditions, since a to quick drying may lead to collapse. Controlled drying may be accomplished by allowing it to take place in an atmosphere which contains components
10 which are present in the liquid surrounding the silica skeleton, or components formed from said liquid at high r temperature. The drying may e.g. take place in a chamber with such an atmosphere, or it may take place while the alcogel is kept almost completely covered, e.g. up to 99%, whereby the
15 same effect is obtained. The drying is suitably carried out at a temperature in the range 40 - 200°C. The drying temperature may also be gradually varied from room temperature to the boiling point of aqueous alcohol.
20 The thereby formed xerogel has a low density (e.g. 0,5 g/cm3 or lower) and has also a homogeneous structure.
Example 1 An alcogel was prepared by hydrolysis and polycondensation of
25 TMOS. The hydrolysis took place with H4OH as catalyst, a stoichiometric amount of water (TMOS:water, molar ratio 1:4) , and with methanol as a solvent. The gel formation took place at approximately 0°C. The alcogel was cast in Pyrex/teflon moulds with a removable bottom of Nescofilm. After up to
30 several hours standing in completely covered condition after the gel formation, the mould with the alcogel was immersed in » an ageing solution of tetraethoxysilane (TEOS) and methanol.
The mould was"removed from the bath after approximately 24 « hours, and the bath was then kept covered for additional 24
35 hours. During the entire periode of immersing and continued storage, the temperature was kept at about 60°C. The gel was then covered to an extent of 97% and was dried at about 60°C and a pressure of one atmosphere. The drying resulted in a monolithic gel having a density in the range 0.42 - 0.73 g/cm3. Different molar ratios between TEOS and methanol in the ageing solutions were used. The density decreases linearly, and correspondingly the pore size increases with increasing amount of TEOS in the ageing liquid and increased time in this liquid. The shrinkage of the alcogel during the drying is in the range 15 - 30% depending on the molar ratio and ageing time. The surface area of the xerogel is in the range 600 - 650 m2/g. The thermal conductivity of the silica xeroge? material formed has been measured down to 0.02 ±0.004 W. mK at 450C.
Example 2 An alcogel was prepared as described in Example 1. After up to several hours of standing in covered condition the mouled with the alcogel was immersed in liquid consisting of methanol and water (e.g. 30 volume % of water) . The liquid mixture was changed three times with 24 hours intervals. The alcogel in the liquid mixtures was kept at room temperature during the entire washing. After four days the washing solution was replaced by a solution of tetraethoxysilane as in Example l. The rest is as in Example 1.
The treatment of the alcogel in the solution of water and methanol causes less shrinkage of the alcogel during drying. The shrinkage of the alcogel during drying is about 13%. The thermal conductivity of the silica xerogel prepared has been measured down to 0.028±0.04W/mK.
The surface area decreases and the pore size increases linearly with increasing amount of water in the liquid mixture used for washing the alcogel.
Example 3
The same procedure as in Examples 1 and 2, but methanol was replaced by ethanol in the liquid mixture used during the washing and as solvent for the tetraalkoxysilane used to stengthen the gel network.

Claims

C L A I M S 1. A process for the preparation of silica xerogel (aerogel) by hydrolysis and polycondensation of a tetraalkoxysilane to form an alcogel which is a silica skeleton surrounded by an aqueous alcohol, whereafter aqueous alcohol is removed by evaporation; c h a r a c t e r i z e d i n t h a t the formed alcogel is brought in contact with a solution of tetraalkoxysilane, the contact is maintained at or above room temperature to εtengten the silica skeleton, whereafter the gel is dried slowly at or above room temperature at approximately atmospheric pressure.
2. The process of claim 1, c h a r a c t e r i z e d i n t h a t the alcogel is brought in contact with a solution of tetraalkoxysilane, preferably in an alcohol.
3. The process of any of claims l and 2, c h a r a c t e r i z e d i n t h a t the alcogel before further contact is washed with an optionally aqueous alcohol.
4. The process of any of claims 1 - 3, c h a r a c t e r i z e d i n t h a t tetramethoxysilane is used for the preparation of the alcogel, which is then brought in contact with a solution of tetraethoxysilane in an alcohol, especially methanol.
5. The process of any of claims 1 - 4, c h a r a c t e r i z e d i n t h a t the contact between the alcogel and the solution of tetraalkoxysilane is maintained at a temperature in the range 20 - 200°C for a period from 6 -hours to 16 days.
6. The process of claim 5, c h a r a c t e r i z e d i n t h a t the subsequent drying is performed within the temperature range 40 - 200°C.
SUBSTITUTE SHEET
7. The process of claim 6, c h a r a c t e r i z e d i n t h a t the drying takes place in an atmosphere which contains components present in the liquid surrounding the silica skeleton, or components which may be formed from the said liquid at higher temperatures, for example by covering up to 99% of the gel surface during drying.
PCT/NO1992/000096 1991-05-24 1992-05-22 Process for the preparation of a silica aerogel-like material WO1992020623A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
AU17852/92A AU662147C (en) 1991-05-24 1992-05-22 Process for the preparation of a silica aerogel-like material
BR9206051A BR9206051A (en) 1991-05-24 1992-05-22 Process for the preparation of silica xerogel (Airgel).
CA002109715A CA2109715A1 (en) 1991-05-24 1992-05-22 Process for the preparation of silica aerogel-like material
EP92910393A EP0646097A1 (en) 1991-05-24 1992-05-22 Process for the preparation of a silica aerogel-like material
JP4510552A JPH06510268A (en) 1991-05-24 1992-05-22 Silica airgel-like material manufacturing method
FI935203A FI935203A (en) 1991-05-24 1993-11-23 FOERFARANDE FOER FRAMSTAELLNING AV ETT SILICA-AEROGELLIKNANDE MATERIAL
NO934233A NO934233D0 (en) 1991-05-24 1993-11-23 Process for preparing a silica aerogel-like material

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO912006A NO912006D0 (en) 1991-05-24 1991-05-24 PROCEDURE FOR THE MANUFACTURE OF A SILICA-AEROGEL-LIKE MATERIAL.
NO912006 1991-05-24

Publications (1)

Publication Number Publication Date
WO1992020623A1 true WO1992020623A1 (en) 1992-11-26

Family

ID=19894166

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1992/000096 WO1992020623A1 (en) 1991-05-24 1992-05-22 Process for the preparation of a silica aerogel-like material

Country Status (7)

Country Link
EP (1) EP0646097A1 (en)
JP (1) JPH06510268A (en)
BR (1) BR9206051A (en)
CA (1) CA2109715A1 (en)
FI (1) FI935203A (en)
NO (2) NO912006D0 (en)
WO (1) WO1992020623A1 (en)

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996014266A1 (en) * 1994-11-03 1996-05-17 Hoechst Aktiengesellschaft Process for preparing aerogels
DE19538333A1 (en) * 1995-10-14 1997-04-17 Basf Ag Process for the subcritical production of aerogels
EP1059267A1 (en) * 1999-06-10 2000-12-13 Dow Corning Corporation Method for preparing hydrophilic silica gels with high pore volume
US6378229B1 (en) 1997-12-19 2002-04-30 Cabot Corporation Method for the sub-critical drying of lyogels to produce aerogels
WO2002034671A1 (en) * 2000-10-24 2002-05-02 Qinetic Limited Solvogels and a method of manufacture of the same
ES2174680A1 (en) * 1999-09-03 2002-11-01 Consejo Superior Investigacion Set of low density hybrid inorganic and organic heat insulation materials consists of sol gel products of polymers alkoxides and fillers, with polycondensation
US6481649B1 (en) 1997-05-02 2002-11-19 Cabot Corporation Method for granulating aerogels
US6620355B1 (en) 1997-05-02 2003-09-16 Cabot Corporation Method for compacting aerogels
US6825260B2 (en) 1998-06-05 2004-11-30 Cabot Corporation Nanoporous interpenetrating organic-inorganic networks
FR2873677A1 (en) * 2004-07-29 2006-02-03 Armines Ass Pour La Rech Et Le Preparation of silica xerogels comprises: treating organo silica gel with hydrophobing agent in the presence of weak acid and solvent; separating obtained hydrophobic organogel; and eliminating solvent from organogel by evaporation
US7297718B2 (en) 1998-01-14 2007-11-20 Cabot Corporation Method of producing substantially spherical lyogels in water insoluble silylating agents
US7303013B2 (en) 2002-12-31 2007-12-04 Baker Hughes Incorporated Method for reducing density of a system fluid and for performing drilling operations using a reduced density system fluid comprising aerogel
US7309722B2 (en) 2002-11-13 2007-12-18 Shin-Etsu Chemical Co. Ltd. Composition for forming porous film, porous film and method for forming the same, interlevel insulator film, and semiconductor device
US7326422B2 (en) 1996-05-29 2008-02-05 Delsitech Oy Dissolvable oxides for biological applications
EP1919829A2 (en) * 2005-08-25 2008-05-14 Keller Companies, Inc. Aerogel and method of manufacturing same
US7737189B2 (en) 2005-04-05 2010-06-15 Instituto Superior Tecnico Process for the preparation, under subcritical conditions, of monolithic xerogels and aerogels of silica/latex hybrids, modified with alkoxysilane groups
WO2014126490A1 (en) 2013-02-15 2014-08-21 Instituto Superior Técnico Flexible hybrid aerogels prepared under subcritical conditions and their preparation process
KR20180029501A (en) * 2016-09-12 2018-03-21 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
KR20180029500A (en) * 2016-09-12 2018-03-21 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
US10149825B2 (en) 2004-02-27 2018-12-11 Delsitech Oy Method for preparing adjustably bioresorbable sol-gel derived SiO2
US10889501B2 (en) 2016-02-24 2021-01-12 Massachusetts Institute Of Technology Solar thermal aerogel receiver and materials therefor
US11170750B2 (en) 2018-04-25 2021-11-09 Massachusetts Institute Of Technology Energy efficient soundproofing window retrofits

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008056987A1 (en) * 2008-11-12 2010-05-20 Rwe Power Ag insulating cartridge
DE102009053784A1 (en) * 2009-11-19 2011-05-26 BSH Bosch und Siemens Hausgeräte GmbH A method for producing a porous pore size SiO 2 xerogel by a bottom-up method via a precursor having organic solid skeletal supports
DE102009053782A1 (en) * 2009-11-19 2011-06-01 BSH Bosch und Siemens Hausgeräte GmbH Porous SiO2 xerogel with characteristic pore size, its drying-stable precursors and its application
JP6191012B2 (en) * 2013-12-12 2017-09-06 パナソニックIpマネジメント株式会社 Insulation
JP7001098B2 (en) * 2017-09-01 2022-01-19 Agc株式会社 Manufacturing method of xerogel, heat insulating material and laminated glass

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE422045B (en) * 1979-04-30 1982-02-15 Dardel Guy Von VIEW TO MAKE SILICA EROGEL IN THE FORM OF A SIGNIFICANT CRACKLESS, PREFERRED TRANSPARENT BLOCK AND USE OF THE SAME IN SOLAR PANELS
US4402927A (en) * 1980-04-22 1983-09-06 Dardel Guy Von Silica aerogel
EP0216278A2 (en) * 1985-09-25 1987-04-01 MERCK PATENT GmbH Spherically shaped silica particles
DE3929219A1 (en) * 1988-09-26 1990-03-29 Leuna Werke Veb Prepn. of silica gel modified with alkoxy:silane - by heating mixt. of gel and silane, percolating with wash liq., and drying in inert gas, for chromatography

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE422045B (en) * 1979-04-30 1982-02-15 Dardel Guy Von VIEW TO MAKE SILICA EROGEL IN THE FORM OF A SIGNIFICANT CRACKLESS, PREFERRED TRANSPARENT BLOCK AND USE OF THE SAME IN SOLAR PANELS
US4402927A (en) * 1980-04-22 1983-09-06 Dardel Guy Von Silica aerogel
EP0216278A2 (en) * 1985-09-25 1987-04-01 MERCK PATENT GmbH Spherically shaped silica particles
DE3929219A1 (en) * 1988-09-26 1990-03-29 Leuna Werke Veb Prepn. of silica gel modified with alkoxy:silane - by heating mixt. of gel and silane, percolating with wash liq., and drying in inert gas, for chromatography

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5759506A (en) * 1994-11-03 1998-06-02 Hoechst Aktiengesellschaft Process for preparing aerogels
WO1996014266A1 (en) * 1994-11-03 1996-05-17 Hoechst Aktiengesellschaft Process for preparing aerogels
DE19538333A1 (en) * 1995-10-14 1997-04-17 Basf Ag Process for the subcritical production of aerogels
US7326422B2 (en) 1996-05-29 2008-02-05 Delsitech Oy Dissolvable oxides for biological applications
US6481649B1 (en) 1997-05-02 2002-11-19 Cabot Corporation Method for granulating aerogels
US6620355B1 (en) 1997-05-02 2003-09-16 Cabot Corporation Method for compacting aerogels
US6378229B1 (en) 1997-12-19 2002-04-30 Cabot Corporation Method for the sub-critical drying of lyogels to produce aerogels
US7297718B2 (en) 1998-01-14 2007-11-20 Cabot Corporation Method of producing substantially spherical lyogels in water insoluble silylating agents
US6825260B2 (en) 1998-06-05 2004-11-30 Cabot Corporation Nanoporous interpenetrating organic-inorganic networks
US6239243B1 (en) 1999-06-10 2001-05-29 Dow Corning Corporation Method for preparing hydrophilic silica gels with high pore volume
EP1059267A1 (en) * 1999-06-10 2000-12-13 Dow Corning Corporation Method for preparing hydrophilic silica gels with high pore volume
ES2174680A1 (en) * 1999-09-03 2002-11-01 Consejo Superior Investigacion Set of low density hybrid inorganic and organic heat insulation materials consists of sol gel products of polymers alkoxides and fillers, with polycondensation
WO2002034671A1 (en) * 2000-10-24 2002-05-02 Qinetic Limited Solvogels and a method of manufacture of the same
US7309722B2 (en) 2002-11-13 2007-12-18 Shin-Etsu Chemical Co. Ltd. Composition for forming porous film, porous film and method for forming the same, interlevel insulator film, and semiconductor device
US8034749B2 (en) 2002-12-31 2011-10-11 Baker Hughes Incorporated Aerogels effective to reduce drilling fluid density
US7303013B2 (en) 2002-12-31 2007-12-04 Baker Hughes Incorporated Method for reducing density of a system fluid and for performing drilling operations using a reduced density system fluid comprising aerogel
US10149825B2 (en) 2004-02-27 2018-12-11 Delsitech Oy Method for preparing adjustably bioresorbable sol-gel derived SiO2
FR2873677A1 (en) * 2004-07-29 2006-02-03 Armines Ass Pour La Rech Et Le Preparation of silica xerogels comprises: treating organo silica gel with hydrophobing agent in the presence of weak acid and solvent; separating obtained hydrophobic organogel; and eliminating solvent from organogel by evaporation
US7737189B2 (en) 2005-04-05 2010-06-15 Instituto Superior Tecnico Process for the preparation, under subcritical conditions, of monolithic xerogels and aerogels of silica/latex hybrids, modified with alkoxysilane groups
EP1919829A2 (en) * 2005-08-25 2008-05-14 Keller Companies, Inc. Aerogel and method of manufacturing same
EP1919829A4 (en) * 2005-08-25 2011-03-23 Keller Companies Inc Aerogel and method of manufacturing same
WO2014126490A1 (en) 2013-02-15 2014-08-21 Instituto Superior Técnico Flexible hybrid aerogels prepared under subcritical conditions and their preparation process
US11851334B2 (en) 2016-02-24 2023-12-26 Massachusetts Institute Of Technology Solar thermal aerogel receiver and materials therefor
US10889501B2 (en) 2016-02-24 2021-01-12 Massachusetts Institute Of Technology Solar thermal aerogel receiver and materials therefor
US10494265B2 (en) 2016-09-12 2019-12-03 Lg Chem, Ltd. Method for producing silica aerogel and silica aerogel produced thereby
EP3345867A4 (en) * 2016-09-12 2018-11-21 LG Chem, Ltd. Method for manufacturing silica aerogel and silica aerogel manufactured thereby
EP3342754A4 (en) * 2016-09-12 2018-11-21 LG Chem, Ltd. Method for manufacturing silica aerogel and silica aerogel manufactured thereby
KR102092770B1 (en) 2016-09-12 2020-03-24 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
KR102092769B1 (en) 2016-09-12 2020-03-24 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
US10604412B2 (en) 2016-09-12 2020-03-31 Lg Chem, Ltd. Method for producing silica aerogel and silica aerogel produced thereby
KR20180029500A (en) * 2016-09-12 2018-03-21 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
US11242255B2 (en) 2016-09-12 2022-02-08 Lg Chem, Ltd. Method for producing silica aerogel and silica aerogel produced thereby
KR20180029501A (en) * 2016-09-12 2018-03-21 주식회사 엘지화학 Method of preparing for silica aerogel and silica aerogel prepared by the same
US11170750B2 (en) 2018-04-25 2021-11-09 Massachusetts Institute Of Technology Energy efficient soundproofing window retrofits
US11749247B2 (en) 2018-04-25 2023-09-05 Massachusetts Institute Of Technology Energy efficient soundproofing window retrofits

Also Published As

Publication number Publication date
JPH06510268A (en) 1994-11-17
NO912006D0 (en) 1991-05-24
FI935203A (en) 1994-01-13
CA2109715A1 (en) 1992-11-26
AU1785292A (en) 1992-12-30
NO934233L (en) 1993-11-23
NO934233D0 (en) 1993-11-23
EP0646097A1 (en) 1995-04-05
BR9206051A (en) 1994-11-15
FI935203A0 (en) 1993-11-23
AU662147B2 (en) 1995-08-24

Similar Documents

Publication Publication Date Title
EP0646097A1 (en) Process for the preparation of a silica aerogel-like material
EP0497966B1 (en) A METHOD FOR PRODUCING METAL OXIDE AEROGELS HAVING DENSITIES LESS THAN 0.02 g/cm?3
US5409683A (en) Method for producing metal oxide aerogels
CA1288313C (en) Process for forming transparent aerogel insulating arrays
EP0018955B1 (en) A method for the preparation of silica aerogel and its use
Gesser et al. Aerogels and related porous materials
US4402927A (en) Silica aerogel
US4432956A (en) Preparation of monolithic silica aerogels, the aerogels thus obtained and their use for the preparation of silica glass articles and of heat-insulating materials
KR101717833B1 (en) Preparation method of hydrophobic silica aerogel
Phalippou et al. Glasses from aerogels: Part 1 The synthesis of monolithic silica aerogels
KR100501758B1 (en) Process for preparing organically modified aerogels in which the salts formed are precipitated out
JP4018174B2 (en) Preparation method of simple substance silica airgel and silica airgel obtained thereby
CA2119369A1 (en) Aerogel matrix composites
Venkateswara Rao et al. Effect of solvents and catalysts on monolithicity and physical properties of silica aerogels
AU686871B2 (en) Subcritical process for drying sol-gel derived porous bodies
US4806328A (en) Method of manufacturing monolithic glass members
JPH0859224A (en) Xerogel,preparation and use of it
CN109019611B (en) Block transparent silica aerogel and rapid preparation method and application thereof
CA2747205A1 (en) Methods of preparing hybrid aerogels
AU662147C (en) Process for the preparation of a silica aerogel-like material
Kumar et al. Synthesis of high surface area silica by solvent exchange in alkoxy derived silica gels
Kuchta et al. About the synthesis and thermal stability of SiO 2-aerogel
WO2020014828A1 (en) Methods for forming aerogels
Pajonk A short history of the preparation of aerogels and carbogels
CA2740818A1 (en) Small pore area material comprising acetic acid

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU BR CA FI JP NO US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU MC NL SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2109715

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 935203

Country of ref document: FI

WWE Wipo information: entry into national phase

Ref document number: 1992910393

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 1994 150157

Country of ref document: US

Date of ref document: 19940428

Kind code of ref document: A

WWP Wipo information: published in national office

Ref document number: 1992910393

Country of ref document: EP

WWR Wipo information: refused in national office

Ref document number: 1992910393

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1992910393

Country of ref document: EP