WO1992020623A1 - Process for the preparation of a silica aerogel-like material - Google Patents
Process for the preparation of a silica aerogel-like material Download PDFInfo
- 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
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/16—Preparation of silica xerogels
- C01B33/163—Preparation 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
Description
Claims
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)
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 |
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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)
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 |
-
1991
- 1991-05-24 NO NO912006A patent/NO912006D0/en unknown
-
1992
- 1992-05-22 JP JP4510552A patent/JPH06510268A/en active Pending
- 1992-05-22 EP EP92910393A patent/EP0646097A1/en not_active Ceased
- 1992-05-22 WO PCT/NO1992/000096 patent/WO1992020623A1/en not_active Application Discontinuation
- 1992-05-22 BR BR9206051A patent/BR9206051A/en not_active Application Discontinuation
- 1992-05-22 CA CA002109715A patent/CA2109715A1/en not_active Abandoned
-
1993
- 1993-11-23 FI FI935203A patent/FI935203A/en not_active Application Discontinuation
- 1993-11-23 NO NO934233A patent/NO934233D0/en unknown
Patent Citations (4)
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)
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 |
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