WO1992020623A1 - Procede de preparation d'un materiau analogue a un aerogel de silice - Google Patents

Procede de preparation d'un materiau analogue a un aerogel de silice Download PDF

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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
English (en)
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 CA002109715A priority Critical patent/CA2109715A1/fr
Priority to EP92910393A priority patent/EP0646097A1/fr
Priority to AU17852/92A priority patent/AU662147C/en
Priority to JP4510552A priority patent/JPH06510268A/ja
Priority to BR9206051A priority patent/BR9206051A/pt
Publication of WO1992020623A1 publication Critical patent/WO1992020623A1/fr
Priority to NO934233A priority patent/NO934233L/no
Priority to FI935203A priority patent/FI935203A/fi

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.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Silicon Compounds (AREA)

Abstract

Procédé de préparation d'un xérogel de silice par hydrolyse et polycondensation d'un tétraalcoxysilane, afin d'obtenir un alcogel, qui est une ossature de silice entourée par un méthanol aqueux supprimé ensuite par évaporation. L'alcogel obtenu est mis en contact avec une solution de tétraalcoxysilane; on maintient le contact à température ambiante ou au-dessus de ladite température, afin de solidifier l'ossature de silice et on fait sécher ensuite le gel lentement à température ambiante ou au-dessus et environ à la pression atmosphérique. Avant de mettre l'alcogel en contact avec la solution de tétraalcoxysilane, on peut le laver avec une solution (par exemple, un méthanol aqueux), afin de modifier les groupes fonctionnels de la surface de l'alcogel.
PCT/NO1992/000096 1991-05-24 1992-05-22 Procede de preparation d'un materiau analogue a un aerogel de silice WO1992020623A1 (fr)

Priority Applications (7)

Application Number Priority Date Filing Date Title
CA002109715A CA2109715A1 (fr) 1991-05-24 1992-05-22 Procede de preparation d'un materiau silicone de type aerogel
EP92910393A EP0646097A1 (fr) 1991-05-24 1992-05-22 Procede de preparation d'un materiau analogue a un aerogel de silice
AU17852/92A AU662147C (en) 1991-05-24 1992-05-22 Process for the preparation of a silica aerogel-like material
JP4510552A JPH06510268A (ja) 1991-05-24 1992-05-22 シリカ　エアロゲル様材料の製造方法
BR9206051A BR9206051A (pt) 1991-05-24 1992-05-22 Processo para a preparação de xerogel de sílica (Aerogel).
NO934233A NO934233L (no) 1991-05-24 1993-11-23 Fremgangsmaate for fremstilling av et silika aerogel-lignende materiale
FI935203A FI935203A (fi) 1991-05-24 1993-11-23 Foerfarande foer framstaellning av ett silika-aerogelliknande material

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO912006A NO912006D0 (no) 1991-05-24 1991-05-24 Fremgangsmaate for fremstilling av et silika-aerogel-lignende materiale.
NO912006 1991-05-24

Publications (1)

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

Family

ID=19894166

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1992/000096 WO1992020623A1 (fr) 1991-05-24 1992-05-22 Procede de preparation d'un materiau analogue a un aerogel de silice

Country Status (7)

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

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996014266A1 (fr) * 1994-11-03 1996-05-17 Hoechst Aktiengesellschaft Procede de production d'aerogels
DE19538333A1 (de) * 1995-10-14 1997-04-17 Basf Ag Verfahren zur unterkritischen Herstellung von Aerogelen
EP1059267A1 (fr) * 1999-06-10 2000-12-13 Dow Corning Corporation Procédé de préparation de gels hydrophiles de silice à volume poreux élevé
US6378229B1 (en) 1997-12-19 2002-04-30 Cabot Corporation Method for the sub-critical drying of lyogels to produce aerogels
WO2002034671A1 (fr) * 2000-10-24 2002-05-02 Qinetic Limited Solvogels et leur procede de fabrication
ES2174680A1 (es) * 1999-09-03 2002-11-01 Consejo Superior Investigacion Materiales termohibridos inorganico-organicos de baja densidad y su procedimiento de obtencion.
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 (fr) * 2004-07-29 2006-02-03 Armines Ass Pour La Rech Et Le Procede d'elaboration de serogels de silice hydrophobes
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 (fr) * 2005-08-25 2008-05-14 Keller Companies, Inc. Aerogel et son procede de fabrication
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 (fr) 2013-02-15 2014-08-21 Instituto Superior Técnico Aérogels hybrides flexibles préparés dans des conditions sous-critiques et leur procédé de préparation
KR20180029501A (ko) * 2016-09-12 2018-03-21 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
KR20180029500A (ko) * 2016-09-12 2018-03-21 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
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 (de) * 2008-11-12 2010-05-20 Rwe Power Ag Isolierkassette
DE102009053782A1 (de) * 2009-11-19 2011-06-01 BSH Bosch und Siemens Hausgeräte GmbH Poröses SiO2-Xerogel mit charakteristischer Porengröße, dessen trocknungsstabile Vorstufen und dessen Anwendung
DE102009053784A1 (de) * 2009-11-19 2011-05-26 BSH Bosch und Siemens Hausgeräte GmbH Verfahren zur Herstellung eines porösen SiO2-Xerogels mit charakteristischer Porengröße durch ein Bottom-Up-Verfahren über eine Vorstufe mit organischen Festkörperskelettstützen
JP6191012B2 (ja) * 2013-12-12 2017-09-06 パナソニックＩｐマネジメント株式会社 断熱材
EP3677618A4 (fr) * 2017-09-01 2021-05-26 AGC Inc. Procédés de production de gel humide et de xérogel

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE422045B (sv) * 1979-04-30 1982-02-15 Dardel Guy Von Sett att framstella silikaaerogel i form av ett vesentligen sprickfritt, foretredesvis transparent block samt anvendning av detsamma i solpaneler
US4402927A (en) * 1980-04-22 1983-09-06 Dardel Guy Von Silica aerogel
EP0216278A2 (fr) * 1985-09-25 1987-04-01 MERCK PATENT GmbH Particules de silice sphériques
DE3929219A1 (de) * 1988-09-26 1990-03-29 Leuna Werke Veb Verfahren und vorrichtung zur herstellung organisch modifizierter silikagele

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE422045B (sv) * 1979-04-30 1982-02-15 Dardel Guy Von Sett att framstella silikaaerogel i form av ett vesentligen sprickfritt, foretredesvis transparent block samt anvendning av detsamma i solpaneler
US4402927A (en) * 1980-04-22 1983-09-06 Dardel Guy Von Silica aerogel
EP0216278A2 (fr) * 1985-09-25 1987-04-01 MERCK PATENT GmbH Particules de silice sphériques
DE3929219A1 (de) * 1988-09-26 1990-03-29 Leuna Werke Veb Verfahren und vorrichtung zur herstellung organisch modifizierter silikagele

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 (fr) * 1994-11-03 1996-05-17 Hoechst Aktiengesellschaft Procede de production d'aerogels
DE19538333A1 (de) * 1995-10-14 1997-04-17 Basf Ag Verfahren zur unterkritischen Herstellung von Aerogelen
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 (fr) * 1999-06-10 2000-12-13 Dow Corning Corporation Procédé de préparation de gels hydrophiles de silice à volume poreux élevé
ES2174680A1 (es) * 1999-09-03 2002-11-01 Consejo Superior Investigacion Materiales termohibridos inorganico-organicos de baja densidad y su procedimiento de obtencion.
WO2002034671A1 (fr) * 2000-10-24 2002-05-02 Qinetic Limited Solvogels et leur procede de fabrication
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 (fr) * 2004-07-29 2006-02-03 Armines Ass Pour La Rech Et Le Procede d'elaboration de serogels de silice hydrophobes
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 (fr) * 2005-08-25 2008-05-14 Keller Companies, Inc. Aerogel et son procede de fabrication
EP1919829A4 (fr) * 2005-08-25 2011-03-23 Keller Companies Inc Aerogel et son procede de fabrication
WO2014126490A1 (fr) 2013-02-15 2014-08-21 Instituto Superior Técnico Aérogels hybrides flexibles préparés dans des conditions sous-critiques et leur procédé de préparation
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 (fr) * 2016-09-12 2018-11-21 LG Chem, Ltd. Procédé de fabrication d'aérogel de silice et aérogel de silice ainsi fabriqué
EP3342754A4 (fr) * 2016-09-12 2018-11-21 LG Chem, Ltd. Procédé de fabrication d'aérogel de silice et aérogel de silice ainsi fabriqué
KR102092769B1 (ko) 2016-09-12 2020-03-24 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
KR102092770B1 (ko) 2016-09-12 2020-03-24 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
US10604412B2 (en) 2016-09-12 2020-03-31 Lg Chem, Ltd. Method for producing silica aerogel and silica aerogel produced thereby
KR20180029500A (ko) * 2016-09-12 2018-03-21 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
US11242255B2 (en) 2016-09-12 2022-02-08 Lg Chem, Ltd. Method for producing silica aerogel and silica aerogel produced thereby
KR20180029501A (ko) * 2016-09-12 2018-03-21 주식회사 엘지화학 실리카 에어로겔의 제조방법 및 이에 의해 제조된 실리카 에어로겔
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
AU662147B2 (en) 1995-08-24
CA2109715A1 (fr) 1992-11-26
JPH06510268A (ja) 1994-11-17
FI935203A (fi) 1994-01-13
NO912006D0 (no) 1991-05-24
EP0646097A1 (fr) 1995-04-05
AU1785292A (en) 1992-12-30
BR9206051A (pt) 1994-11-15
FI935203A0 (fi) 1993-11-23
NO934233D0 (no) 1993-11-23
NO934233L (no) 1993-11-23

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