CN106865558A - Normal pressure prepares the method and obtained aerosil of aerosil - Google Patents
Normal pressure prepares the method and obtained aerosil of aerosil Download PDFInfo
- Publication number
- CN106865558A CN106865558A CN201710172205.1A CN201710172205A CN106865558A CN 106865558 A CN106865558 A CN 106865558A CN 201710172205 A CN201710172205 A CN 201710172205A CN 106865558 A CN106865558 A CN 106865558A
- Authority
- CN
- China
- Prior art keywords
- organic solvent
- polar organic
- gel
- acid
- aerosil
- Prior art date
- Legal status (The legal status 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 status listed.)
- Pending
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
- C01B33/14—Colloidal silica, e.g. dispersions, gels, sols
- C01B33/157—After-treatment of gels
- C01B33/158—Purification; Drying; Dehydrating
- C01B33/1585—Dehydration into aerogels
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/11—Powder tap density
Abstract
The present invention provides the method and obtained aerosil that a kind of normal pressure prepares aerosil, and it is comprised the following steps：(1) after by inorganic silicon source dilute with water, mix to carry out acid-base reaction with acid, obtain silica sol；(2) silica sol is carried out into gel, burin-in process is carried out to the gel again after gel-forming, obtain wet gel；(3) to addition modifying agent base fluid in wet gel to the wet gel complete wetting, again to addition concentrated acid or high alkali liquid in system, and surface modification treatment is carried out in confined conditions or in the device with condensing reflux equipment, until the gel is all hydrophobic by hydrophilic modifying；(4) treatment is dried to the modified aeroge obtained in step (3), obtains aerosil；Wherein, the method also includes the silica sol obtained to step (1), and/or the operation of addition polar organic solvent or the polar organic solvent aqueous solution in the system before concentrated acid or high alkali liquid is added to step (3).
Description
Technical field
Method and obtained silica gas that normal pressure prepares aerosil are industrialized the present invention relates to a kind of
Gel, belongs to technical field of nano material.
Background technology
Aerosil is a kind of light nanoporous material, and it has high porosity, bigger serface, low-density
And low thermal conductivity, these features cause silica aerogel material in calorifics, acoustics, optics, microelectronics, particle detection side
There is very wide application potential in face.Although aerosil excellent performance, its preparation cost is too high, this very great Cheng
Its popularization and application is limited on degree.
At present, supercritical drying process is used the preparation of aerosil more, but supercritical process equipment is complicated,
High cost, and there is certain danger, therefore constant pressure and dry technique is increasingly becoming everybody focus of attention.
Early in eighties of last century nineties, Deshpande, Douglas of University of New Mexico of the U.S. et al. (Deshpande
R,Hua D-W,Smith DM,Brinker CJ.Pore structure evolution in silica gel during
aging/drying.III.Effects of surface tension.J Non-Cryst Solids.1992；144(0):
32-44) first with organic silicon source as presoma, by collosol and gel, using the modified method in exchange of solvent, surface in normal pressure bar
Part is successfully prepared aerosil；Subsequent domestic and foreign scholars are numerous and confused based on this, and silica is prepared to normal pressure
Aeroge has carried out substantial amounts of research, and has delivered substantial amounts of article and patent.Current normal pressure prepares aerosil work
It is raw material that organic silicon source is used skill more, but organic silicon source high cost, so being increasingly becoming people by silicon source of cheap waterglass
The emphasis studied.It is silicon source presoma to be disclosed with waterglass such as patent CN103818912A, and absolute ethyl alcohol is solvent, respectively
Acid, be hydrolyzed under base catalysis, polycondensation reaction, obtain wet gel, it is aging to carry out drying with water bath, multiple exchange of solvent, through table
The modified classification at ambient pressure in face is dried to obtain the technical scheme of low-density silicon dioxide aerogel.Additionally, patent CN
104030301A also with waterglass as silicon source, by addition, do not precipitate by chloride ion-containing and being generated containing sour organic solvent for fluorine ion,
Filtered mode removes precipitation again, obtains high-purity silicasol, after through sol-gel, aging, acidifying, modified, dried
Journey, obtains silica aerogel material.Although can in atmospheric conditions prepare the pretty good gas of performance by silicon source of waterglass
Gel, but long preparation period (aging, exchange of solvent, surface modified etc. step need a couple of days) and organic solvent consumption are (more greatly
Secondary exchange of solvent) etc. intrinsic shortcoming be not resolved.
In order to solve these problems, some researchers attempt preparing titanium dioxide using the modified one-step method of exchange of solvent and surface
(Ni Wen, Liang Tao, Yang Hailong, Xu Guoqiang, industrial waterglass prepare nano-pore SiO for raw material for silica aerogel, such as Ni Wen et al.2
Aerogel block body material, Henan chemical industry, 24,2007) with waterglass as silicon source, silica aerogel is prepared using one-step method, it compares table
Area is 643m2/ g, but the modified dosage of one-step method consumption is too big, and be difficult to reclaim.Liu Guangwu of Tongji University et al. (Liu
Light is military, Zhou Bin, Ni Xingyuan, Shen Jun, Du Ai, and motherland's celebrating, waterglass is the super-hydrophobic SiO in source2Aerogel block body is prepared and table
Levy, silicate journal, 40 (1), 2012) with waterglass as silicon source, second is replaced using ethanol/HMDO/concentrated hydrochloric acid
Alcohol/trim,ethylchlorosilane/n-hexane carries out one-step method and prepares silica aerogel block, but its preparation technology is complicated and the time compared with
It is long.
Therefore it provides a kind of short preparation period, low production cost, and gained aerosil product have it is excellent
The method of the aerosil of performance has turned into the technical problem of this area urgent need to resolve.
The content of the invention
In order to solve above-mentioned shortcoming and defect, silica airsetting is prepared it is an object of the invention to provide a kind of normal pressure
The method of glue.
It is preparation-obtained the present invention also aims to provide the method for preparing aerosil by above-mentioned normal pressure
Aerosil.
To reach above-mentioned purpose, on the one hand, the invention provides a kind of method that normal pressure prepares aerosil, its
Comprise the following steps：
(1) colloidal sol is prepared：After by inorganic silicon source dilute with water, mix to carry out acid-base reaction with acid, obtain silica sol；
(2) gel, aging：The silica sol that step (1) is obtained is carried out into gel, the gel is carried out again after gel-forming
Burin-in process, obtains wet gel；
(3) surface is modified：Soaked completely to modifying agent base fluid to the wet gel is added in the wet gel obtained in step (2)
Profit, then to addition concentrated acid or high alkali liquid in system, and enter in confined conditions or in the device with condensing reflux equipment
Row surface modification treatment, until the gel is all hydrophobic by hydrophilic modifying；
(4) dry：Modified aeroge to being obtained in step (3) is dried treatment, obtains the silica
Aeroge；
Wherein, the method also includes the silica sol obtained to step (1), and/or adds concentrated acid or concentrated base to step (3)
The operation of polar organic solvent or the polar organic solvent aqueous solution is added in system before liquid.
The present invention is to modifying agent base fluid in methods described step (3) and polar organic solvent or the polar organic solvent aqueous solution
Addition sequence do not make specific requirement, modifying agent base fluid can with polar organic solvent or the polar organic solvent aqueous solution simultaneously plus
Enter, it is also possible to first to modifying agent base fluid is added in wet gel, add polar organic solvent or the polar organic solvent aqueous solution, but
It is in the preferred embodiment of the present invention, generally first have to addition polar organic solvent or polarity in wet gel in step (3)
Machine solvent aqueous solution, adds modifying agent base fluid after being sufficiently mixed.
According to specific embodiments of the present invention, it is preferable that when the method provided using the present invention prepares silica airsetting
During rubber mat pad, because surface modification treatment process cannot be stirred, now, the preparation method step (3) is：First will be modified
Agent base fluid mixes with concentrated acid or high alkali liquid, then gained mixed liquor is added complete to the wet gel in step (2) wet gel for obtaining
Surface modification treatment is carried out in confined conditions or in the device with condensing reflux equipment after full infiltration, until the gel
It is all hydrophobic by hydrophilic modifying.
According to specific embodiments of the present invention, in the method that the normal pressure prepares aerosil, dry as this
Field conventional technical means, the present invention do not have specific requirement to drying process, its can be normal heating dry, or
Vacuum drying, while the present invention does not also make particular requirement to dry temperature and time, those skilled in the art can be according to existing
Field operation needs to select suitable drying temperature and time, but drying temperature is not to be exceeded 200 DEG C.
In the described method, it is preferable that the inorganic silicon source includes waterglass, Ludox and from flyash or farming
The solid, liquid state silica extracted in thing discarded object.Wherein, solid, liquid state two is extracted from flyash or agricultural waste material
The technology of silica is this area conventional technical means, and solid silica refers to sodium metasilicate crystal, and liquid silica is
Refer to sodium silicate solution, i.e. waterglass.
In the described method, it is preferable that water described in step (1) is 1 with the volume ratio of inorganic silicon source:1-1:6.Its
In, water used is deionized water or running water.
In the described method, it is preferable that acid described in step (1) is included in hydrochloric acid, sulfuric acid, nitric acid, acetic acid and phosphoric acid
Any one, more preferably hydrochloric acid.
In the described method, it is preferable that the pH value of the silica sol obtained in step (1) is 1-5.
In the described method, it is preferable that to the amount of the polar organic solvent added in the silica sol that step (1) is obtained
It is not less than the 25% of the silica sol volume；
It is highly preferred that the polar organic solvent include methyl alcohol, ethanol, acetone, ethylene glycol and isopropanol in one kind or
Several combinations, more preferably ethanol；
It is more preferred still that the volume content of polar organic solvent is not less than 50% in the polar organic solvent aqueous solution.
According to specific embodiment of the present invention, methods described also includes the silica sol and/or the step that are obtained to step (1)
Suddenly (3) add the operation of addition polar organic solvent or the polar organic solvent aqueous solution in the system after modifying agent base fluid, preferably
To add polar organic solvent or the polar organic solvent aqueous solution in the silica sol that is only obtained to step (1), before gel plus
Enter polar organic solvent or the polar organic solvent aqueous solution, can avoid adding polar organic solvent or pole in step (3)
Property aqueous solutions of organic solvent, now the consumption of concentrated acid or high alkali liquid can also be reduced suitably in modifying process, and modified product
Raw water phase waste liquid also can be reduced accordingly.
In the described method, the gel process described in step (2) is using the one kind included in standing, heating and microwave
What the combination of mode or various ways was realized.Wherein, time of repose determines that its pH value is higher according to the pH value of silica sol,
Time of repose is shorter, and pH value is lower, and time of repose is more long；And heating-up temperature is usually no more than 60 DEG C, microwave heating frequency is
2450MHz。
In the described method, it is preferable that the temperature of step (2) described burin-in process is 0-70 DEG C, and the time is 0.5-6h.
In the described method, it is preferable that the modifying agent base fluid described in step (3) includes volatile silicone oil or contains
The non-polar organic solvent of volatile silicone oil.
In the described method, it is preferable that the volatile silicone oil contains the nonpolar organic of volatile silicone oil
The consumption of solvent is 1.5-3 times of wet gel volume.
In the described method, it is preferable that the volatile silicone oil includes HMDO, the silica of prestox three
The combination of one or more in alkane, octamethylcy-clotetrasiloxane and decamethylcyclopentaandoxane；The more preferably silicon of hexamethyl two
Oxygen alkane.
In the described method, it is preferable that the non-polar organic solvent is included in n-hexane, hexamethylene or normal heptane
It is a kind of.
In the described method, it is preferable that in the non-polar solven containing volatile silicone oil, volatile silicone oil
Volume content be not less than 10%.
In the described method, it is preferable that the temperature of surface modification treatment described in step (3) is 0-70 DEG C, and the time is
1-6h。
In the described method, it is preferable that the polarity added in the system before concentrated acid or high alkali liquid is added to step (3)
The amount of organic solvent is 1/2-1 times of wet gel volume.
It is highly preferred that the polar organic solvent include methyl alcohol, ethanol, acetone, ethylene glycol and isopropanol in one kind or
Several combinations, more preferably ethanol；
It is more preferred still that in the aqueous solution containing polar organic solvent, the volume content of polar organic solvent is not less than
50%.
In the described method, it is preferable that concentrated acid described in step (3) includes appointing in hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid
One kind, more preferably hydrochloric acid；The molar concentration of the concentrated acid is not less than 6mol/L；
The high alkali liquid is included in sodium hydrate aqueous solution, potassium hydroxide aqueous solution, calcium hydroxide aqueous solution and ammoniacal liquor
Any one, more preferably sodium hydrate aqueous solution；The molar concentration of the high alkali liquid is not less than 6mol/L.
In the described method, it is preferable that when in step (1) and step (3) simultaneously add polar organic solvent or polarity
During aqueous solutions of organic solvent, the addition of concentrated acid or high alkali liquid is the 1/10-4/5 of wet gel volume.
In the described method, it is preferable that when addition polar organic solvent or the polar organic solvent aqueous solution in step (3)
When, the addition of concentrated acid or high alkali liquid is the 1/5-4/5 of wet gel volume.
In the described method, it is preferable that when addition polar organic solvent or the polar organic solvent aqueous solution in step (1)
When, the addition of concentrated acid or high alkali liquid is the 1/10-1/8 of wet gel volume.
According to specific embodiments of the present invention, in the described method, polarity is added to have in step (1) is to silica sol
Machine solvent or the polar organic solvent aqueous solution, when being constituted optimization to carry out sol ingredient, the modifying agent base fluid described in step (3)
Non-polar organic solvent including volatile silicone oil or containing volatile silicone oil；
The consumption of the volatile silicone oil or the non-polar organic solvent containing volatile silicone oil is wet gel volume
1.5-3 times；
The volatile silicone oil include HMDO, octamethyltrisiloxane, octamethylcy-clotetrasiloxane and
The combination of one or more in decamethylcyclopentaandoxane；Preferably HMDO；
The non-polar organic solvent includes the one kind in n-hexane, hexamethylene or normal heptane；
In the non-polar solven containing volatile silicone oil, the volume content of volatile silicone oil is not less than 10%.
According to method of the present invention, in specific embodiment of the present invention, in step (4) using vacuum drying or
Normal pressure classification drying mode is dried treatment to the modified aeroge obtained in step (3).
On the other hand, present invention also offers two that the method that aerosil is prepared by above-mentioned normal pressure is prepared
Silica aerogel, it is preferable that the tap density of the aerosil is 0.05-0.20g/cm3, thermal conductivity factor is
0.015-0.030W/ (mK), contact angle is not less than 160 °.
It is contemplated that preparing hydrophobic silica aerogel technique week for the constant pressure and dry that current this area is used
The problems such as phase is long big with solvent consumption, it is proposed that a kind of normal pressure that industrializes prepares the method for aerosil and by the party
The aerosil that method is prepared.The present invention is with including waterglass, Ludox and from flyash or crop waste
The cheap inorganic silicon source such as mushy stage silica extracted in thing is presoma, first passes through sol-gal process and prepares wet gel,
Again with volatile silicone oils as modifying agent, a step surface modification technology is carried out in acid condition or under alkalescence condition, again finally
Drying is classified by vacuum drying or normal pressure, final products are obtained.Aerosil is prepared in normal pressure of the present invention
Method in using corresponding device or mould and then can prepare including powder, block and composite (such as dioxy
SiClx aeroge felt pan) in interior aerosil product.
It is provided by the present invention industrialize normal pressure prepare aerosil method process cycle it is short, solvent consumption
It is few, low production cost；The aerosil product prepared by the method has relatively low density and good hydrophobic
Performance, and its thermal conductivity factor is also extremely low, is highly suitable to be applied for heat preservation and insulation field.
Compared with the method that the conventional normal pressure in this area prepares aerosil, the present invention has following notable
Advantage：
Using inorganic silicon source that is cheap, being readily available, polar organic solvent (such as ethanol) used can also be aqueous, and this is caused
Raw material and solvent cost decline to a great extent；
Whole technological process can be completed in 12h, and compared with this area, conventional atmospheric preparation method (3-5 days) manufacturing cycle is big
It is big to shorten；
Using a step be modified method, not only the more conventional atmospheric preparation method of organic solvent consumption greatly reduce, Er Qiebiao
The modified process in face is modified to finish rear gel it is expected that i.e., before modified, gel is hydrophilic, and it is sunk in lower floor's water phase
Hydrophobic oleophilic oil, it can be floated up in upper oil phase, can now be finished to modified with visual inspection modifying process；
Using volatile silicone oils as modifying agent, modifying agent can be reclaimed, and it is prepared by the conventional normal pressure in this area
Silane coupler being used method as modifying agent, reactivity is high and cannot reclaim more.
Specific embodiment
In order to be more clearly understood to technical characteristic of the invention, purpose and beneficial effect, in conjunction with detail below
Embodiment technical scheme is carried out it is described further below, but it is not intended that to it is of the invention can practical range limit
It is fixed.
Embodiment 1
Present embodiments provide it is a kind of industrialize the method that normal pressure prepares aerosil, it includes following step
Suddenly：
(1) alkaline silica sol that 50mL mass concentrations are 30% and 150mL deionized waters are mixed in beaker first,
The Ludox that stirring 5min is diluted；15mL concentrated hydrochloric acids are taken to be mixed and stirred for pH value with the silicon sol solution after dilution
To 4 or so, stop stirring.
(2) silica sol that step (1) is obtained, is carried out into standing gel, after gel-forming again to the gel at normal temperatures
Aging 1h, obtains wet gel.
(3) wet gels of the 50mL after aging, is taken, a container (routine that this area uses with agitating device is added
Device), it is subsequently adding ethanol water and 100mL octamethylcy-clotetrasiloxane modifying agent bases that 50mL concentration is 95% (wt)
Liquid, is stirred mixing, at 50 DEG C after NaOH (concentration the is 6mol/L) aqueous solution for after wet gel complete wetting, adding 20mL
Continue to stir 2h in water-bath to carry out surface modification treatment, until the gel is all hydrophobic by hydrophilic modifying.
(4) container bottom cock, is opened, the liquid in container is released；Solid portion is transferred into air dry oven to enter
Row constant pressure and dry, dries 1 hour at 60 DEG C, is dried 2 hours at 120 DEG C, is dried 3 hours at 150 DEG C, obtains silica airsetting
Glue product.
Measure the performance parameter of the aerosil product that the present embodiment is prepared：Tap density 0.083g/mL,
Thermal conductivity factor 0.019W/ (mK), 169 ° of contact angle.
As can be seen here, the aerosil product that the embodiment of the present invention 1 is prepared has relatively low density and good
Good hydrophobic performance, and its thermal conductivity factor is also extremely low, is highly suitable to be applied for heat preservation and insulation field.
Embodiment 2
Present embodiments provide it is a kind of industrialize the method that normal pressure prepares aerosil, it includes following step
Suddenly：
(1) alkaline silica sol that 50mL mass concentrations are 30% and 150mL deionized waters are mixed in beaker first,
The Ludox that stirring 5min is diluted；15mL concentrated hydrochloric acids are taken to be mixed and stirred for pH value with the silicon sol solution after dilution
To 4 or so, stop stirring；Add the ethanol water that 50mL concentration is 95% (wt).
(2) silica sol that step (1) is obtained, is carried out into standing gel, after gel-forming again to the gel at normal temperatures
Aging 1h, obtains wet gel.
(3) wet gels of the 50mL after aging, is taken, a container (routine that this area uses with agitating device is added
Device), 100mL octamethylcy-clotetrasiloxane modifying agent base fluids are subsequently adding, after after wet gel complete wetting, add 5mL's
NaOH (concentration is 6mol/L) aqueous solution is stirred mixing, continues to stir 2h in 50 DEG C of water-baths to carry out the modified place in surface
Reason, until the gel is all hydrophobic by hydrophilic modifying.
(4) container bottom cock, is opened, the liquid in container is released；Solid portion is transferred into air dry oven to enter
Row constant pressure and dry, dries 1 hour at 60 DEG C, is dried 2 hours at 120 DEG C, is dried 3 hours at 150 DEG C, obtains silica airsetting
Glue product.
Measure the performance parameter of the aerosil product that the present embodiment is prepared：Tap density 0.091g/mL,
Thermal conductivity factor 0.020W/ (mK), 166 ° of contact angle.
As can be seen here, the aerosil product that the embodiment of the present invention 2 is prepared has relatively low density and good
Good hydrophobic performance, and its thermal conductivity factor is also extremely low, is highly suitable to be applied for heat preservation and insulation field.
Embodiment 3
Present embodiments provide it is a kind of industrialize the method that normal pressure prepares aerosil, it includes following step
Suddenly：
(1), 40mL is purified from flyash SiO first2Alkaline extraction and 80mL running water mix in beaker,
The SiO that stirring 5min is diluted2Solution；Acetic acid is dropped into SiO2Solution ＆ stir, to pH value to 4 or so, stop being added dropwise and
Stirring；Add 40mL isopropanols.
(2) colloidal sol that the pH value obtained in step (1) is 4, is poured into size for 13cm x 13cm and equipped with 10mm thickness glass
In the mould (conventional equipment that this area uses) of glass fiber felt pan, make the felt pan in solution complete wetting mould and stand solidifying
Glue；After gel in 60 DEG C of environment accelerated ageing 1h, obtain the felt pan containing wet gel.
(3) the felt pan clot containing wet gel after, will be aging is put into a closed container, is subsequently adding 320mL (this
The consumption of modifying agent base fluid is calculated in embodiment on the basis of felt pan volume) n-hexane and HMDO by volume
It is 1:The modifying agent base fluid of 1 mixing, after after felt pan volume complete wetting, adds 20mL concentrated ammonia liquors (14mol/ to submerge felt pan volume
L modified (it is 45 DEG C that water-bath controls modification temperature) 4 hours) are stood, until the gel is all hydrophobic by hydrophilic modifying.
(4) closed container, is opened, modified clot felt pan is taken out.
(5) clot felt pan, is transferred into air dry oven carries out constant pressure and dry, is dried 1 hour at 60 DEG C, is done at 120 DEG C
Dry 2 hours, dried 3 hours at 150 DEG C, obtain aerosil felt pan.
Measure the performance parameter of the aerosil product that the present embodiment is prepared：Thermal conductivity factor 0.020W/
(mK), 165 ° of contact angle.
As can be seen here, the aerosil felt pan that the embodiment of the present invention 3 is prepared has good hydrophobic performance
With extremely low thermal conductivity factor.
Embodiment 4
Present embodiments provide it is a kind of industrialize the method that normal pressure prepares aerosil, it includes following step
Suddenly：
(1) industrial waterglass colloidal sol that 50mL mass concentrations are 30% and 100mL deionized waters are mixed in beaker first,
Close, stirring 5min obtains waterglass weak solution；15mL concentrated hydrochloric acids are taken to be mixed and stirred for the waterglass weak solution after dilution
To pH value to 4 or so, stop stirring, add the ethanol water that 50mL concentration is 95% (wt).
(2) silica sol that step (1) is obtained, is carried out into standing gel, again to the gel at 50 DEG C after gel-forming
Aging 4h, obtains wet gel.
(3) wet gels of the 50mL after aging, is taken, a container (routine that this area uses with agitating device is added
Device), the hexane solution of the octamethyltrisiloxane that 100mL volumetric concentrations are 50% is subsequently adding as modifying agent base
Liquid, is stirred mixing, then continue in 60 DEG C of water-baths after the 98wt% concentrated sulfuric acids for after wet gel complete wetting, adding 5mL
6h is to carry out surface modification treatment for stirring, until the gel is all hydrophobic by hydrophilic modifying.
(4) container bottom cock, is opened, the liquid in container is released；Solid portion is transferred into air dry oven to enter
Row constant pressure and dry, dries 1 hour at 60 DEG C, is dried 2 hours at 120 DEG C, is dried 3 hours at 150 DEG C, obtains silica airsetting
Glue product.
Measure the performance parameter of the aerosil product that the present embodiment is prepared：Tap density 0.10g/mL,
Thermal conductivity factor 0.021W/ (mK), 160 ° of contact angle.
As can be seen here, the aerosil product that the embodiment of the present invention 4 is prepared has relatively low density and good
Good hydrophobic performance, and its thermal conductivity factor is also extremely low, is highly suitable to be applied for heat preservation and insulation field.
Embodiment 5
Present embodiments provide it is a kind of industrialize the method that normal pressure prepares aerosil, it includes following step
Suddenly：
(1) industrial waterglass colloidal sol that 50mL mass concentrations are 30% and 100mL deionized waters are mixed in beaker first,
Close, stirring 5min obtains waterglass weak solution；15mL concentrated hydrochloric acids are taken to be mixed and stirred for the waterglass weak solution after dilution
To pH value to 4 or so, stop stirring, add the ethanol water that 100mL concentration is 50% (wt).
(2) silica sol that step (1) is obtained, is carried out into standing gel, again to the gel at 60 DEG C after gel-forming
Aging 6h, obtains wet gel.
(3) wet gels of the 50mL after aging, is taken, a container (routine that this area uses with agitating device is added
Device), the mixed modifier base fluid of 100mL octamethylcy-clotetrasiloxanes and decamethylcyclopentaandoxane is subsequently adding, treat wet solidifying
After glue complete wetting, the concentrated hydrochloric acid (12mol/L) for adding 6.25mL is stirred mixing, then continues to stir in 45 DEG C of water-baths
4h is to carry out surface modification treatment, until the gel is all hydrophobic by hydrophilic modifying.
(4) container bottom cock, is opened, the liquid in container is released；Solid portion is transferred into air dry oven to enter
Row constant pressure and dry, dries 1 hour at 60 DEG C, is dried 2 hours at 120 DEG C, is dried 3 hours at 150 DEG C, obtains silica airsetting
Glue product.
Measure the performance parameter of the aerosil product that the present embodiment is prepared：Tap density 0.09g/mL,
Thermal conductivity factor 0.020W/ (mK), 162 ° of contact angle.
As can be seen here, the aerosil product that the embodiment of the present invention 5 is prepared has relatively low density and good
Good hydrophobic performance, and its thermal conductivity factor is also extremely low, is highly suitable to be applied for heat preservation and insulation field.
Claims (10)
1. a kind of method that normal pressure prepares aerosil, it is comprised the following steps：
(1) colloidal sol is prepared：After by inorganic silicon source dilute with water, mix to carry out acid-base reaction with acid, obtain silica sol；
Preferably, water described in step (1) and the volume ratio of inorganic silicon source are 1:1-1:6；
It is further preferred that the pH value of the silica sol is 1-5；
(2) gel, aging：The silica sol that step (1) is obtained is carried out into gel, the gel is carried out again after gel-forming aging
Treatment, obtains wet gel；
Preferably, the temperature of the burin-in process is 0-70 DEG C, and the time is 0.5-6h；
(3) surface is modified：To addition modifying agent base fluid in the wet gel obtained in step (2) to the wet gel complete wetting, then
To addition concentrated acid or high alkali liquid in system, and surface is carried out in confined conditions or in the device with condensing reflux equipment
Modification, until the gel is all hydrophobic by hydrophilic modifying；
Preferably, the temperature of the surface modification treatment is 0-70 DEG C, and the time is 1-6h；
(4) dry：Modified aeroge to being obtained in step (3) is dried treatment, obtains the silica airsetting
Glue；
Wherein, the method also includes the silica sol that is obtained to step (1), and/or before adding concentrated acid or high alkali liquid to step (3)
System in add the operation of polar organic solvent or the polar organic solvent aqueous solution；
Polar organic solvent or the polar organic solvent aqueous solution are added in the silica sol for preferably obtaining to step (1).
2. method according to claim 1, it is characterised in that when preparing aerosil felt pan using methods described
When, the preparation method step (3) is：
Modifying agent base fluid is mixed with concentrated acid or high alkali liquid first, then the wet gel that gained mixed liquor addition step (2) is obtained
In be modified to carrying out surface after the wet gel complete wetting in confined conditions or in the device with condensing reflux equipment
Treatment, until the gel is all hydrophobic by hydrophilic modifying.
3. method according to claim 1 and 2, it is characterised in that the inorganic silicon source include waterglass, Ludox and
The solid, liquid state silica extracted from flyash or agricultural waste material.
4. method according to claim 1 and 2, it is characterised in that acid described in step (1) includes hydrochloric acid, sulfuric acid, nitre
Any one in acid, acetic acid and phosphoric acid, preferably hydrochloric acid.
5. method according to claim 1 and 2, it is characterised in that to the pole added in the silica sol that step (1) is obtained
The amount of property organic solvent is not less than the 25% of the silica sol volume.
6. method according to claim 1 and 2, it is characterised in that the modifying agent base fluid described in step (3) includes waving
Hair property silicone oil or the non-polar organic solvent containing volatile silicone oil；
Preferably, the consumption of the volatile silicone oil or the non-polar organic solvent containing volatile silicone oil is wet gel body
Long-pending 1.5-3 times；
It is further preferred that the volatile silicone oil includes HMDO, octamethyltrisiloxane, the silica of prestox ring four
The combination of one or more in alkane and decamethylcyclopentaandoxane；More preferably HMDO；
It is further preferred that the non-polar organic solvent includes the one kind in n-hexane, hexamethylene or normal heptane；
It is further preferred that in the non-polar solven containing volatile silicone oil, the volume content of volatile silicone oil is not less than
10%.
7. method according to claim 1 and 2, it is characterised in that add the system before concentrated acid or high alkali liquid to step (3)
The amount of middle added polar organic solvent is 1/2-1 times of wet gel volume.
8. the method according to claim 5 or 7, it is characterised in that the polar organic solvent includes methyl alcohol, ethanol, third
The combination of one or more in ketone, ethylene glycol and isopropanol, preferably ethanol；
It is further preferred that in the aqueous solution containing polar organic solvent, the volume content of polar organic solvent is not less than 50%.
9. method according to claim 1 and 2, it is characterised in that concentrated acid described in step (3) includes hydrochloric acid, sulfuric acid, nitre
Any one in acid and phosphoric acid, preferably hydrochloric acid, the molar concentration of the concentrated acid is not less than 6mol/L；
The high alkali liquid includes any in sodium hydrate aqueous solution, potassium hydroxide aqueous solution, calcium hydroxide aqueous solution and ammoniacal liquor
Plant, preferably sodium hydrate aqueous solution, the molar concentration of the high alkali liquid is not less than 6mol/L；
Wherein, it is further preferred that when addition polar organic solvent or polar organic solvent are water-soluble simultaneously in step (1) and step (3)
During liquid, the addition of concentrated acid or high alkali liquid is the 1/10-4/5 of wet gel volume；
It is further preferred that when adding polar organic solvent or the polar organic solvent aqueous solution in the step (3), concentrated acid or high alkali liquid
Addition is the 1/5-4/5 of wet gel volume；
It is further preferred that when adding polar organic solvent or the polar organic solvent aqueous solution in the step (1), concentrated acid or high alkali liquid
Addition is the 1/10-1/8 of wet gel volume.
10. the normal pressure described in any one of claim 1-9 prepares the silica that the method for aerosil is prepared
Aeroge, it is preferable that the tap density of the aerosil is 0.05-0.20g/cm3, thermal conductivity factor is 0.015-
0.030W/ (mK), contact angle is not less than 160 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710172205.1A CN106865558A (en) | 2017-03-22 | 2017-03-22 | Normal pressure prepares the method and obtained aerosil of aerosil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710172205.1A CN106865558A (en) | 2017-03-22 | 2017-03-22 | Normal pressure prepares the method and obtained aerosil of aerosil |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106865558A true CN106865558A (en) | 2017-06-20 |
Family
ID=59172475
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710172205.1A Pending CN106865558A (en) | 2017-03-22 | 2017-03-22 | Normal pressure prepares the method and obtained aerosil of aerosil |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106865558A (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108147415A (en) * | 2018-01-04 | 2018-06-12 | 中国科学技术大学 | A kind of preparation method of silica aerogel material |
| CN108793173A (en) * | 2018-08-01 | 2018-11-13 | 中国科学技术大学 | A method of improved silica aerogel material is prepared using outer circulation mode constant pressure and dry |
| CN109046190A (en) * | 2018-09-27 | 2018-12-21 | 广东工业大学 | A kind of pectin dioxide composite silica aerogel and the preparation method and application thereof |
| CN109467094A (en) * | 2018-12-25 | 2019-03-15 | 安徽确成硅化学有限公司 | A kind of preparation method preparing functional white carbon black using the leaf of bamboo |
| CN110386607A (en) * | 2018-04-19 | 2019-10-29 | 卢序 | The preparation method of aeroge |
| CN110590014A (en) * | 2019-09-17 | 2019-12-20 | 济南大学 | Method for purifying electroplating wastewater and application of obtained xerogel in glass |
| CN111304910A (en) * | 2020-02-14 | 2020-06-19 | 中南大学 | Ceramic fiber/hydrophobic silicon dioxide aerogel composite material and preparation method thereof |
| CN114122397A (en) * | 2021-10-12 | 2022-03-01 | 湖南金硅科技有限公司 | Carbon nanotube-connected dual-carbon-layer-coated mesoporous silica composite material and preparation method and application thereof |
| CN114538454A (en) * | 2022-01-28 | 2022-05-27 | 江苏安珈新材料科技有限公司 | Method for preparing silica aerogel by using alkaline silica sol |
| WO2023009065A3 (en) * | 2021-07-27 | 2023-04-13 | Singapore Polytechnic | Method for making silica aerogel blanket |
| WO2023226710A1 (en) * | 2022-05-27 | 2023-11-30 | 中化学华陆新材料有限公司 | Method for preparing silicon dioxide aerogel or composite product thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101244826A (en) * | 2008-03-20 | 2008-08-20 | 绍兴纳诺气凝胶新材料研发中心有限公司 | Method for producing silicon dioxide silica aerogel by drying in atmosphere pressure with rice hull as raw material |
| CN101259964A (en) * | 2008-03-20 | 2008-09-10 | 绍兴纳诺气凝胶新材料研发中心有限公司 | Constant pressure and dry preparation method for high-performance silicon dioxide aerogel by using rice husk ash as raw material |
| CN102557052A (en) * | 2012-03-05 | 2012-07-11 | 中国科学院上海硅酸盐研究所 | Method for rapidly preparing low-density silicon oxide aerogel |
| CN102765725A (en) * | 2012-08-10 | 2012-11-07 | 蓝烟（北京）科技有限公司 | Method for preparing hydrophobic silica aerogel with low cost |
| CN103818912A (en) * | 2014-01-21 | 2014-05-28 | 合肥科斯孚安全科技有限公司 | Method for preparing silicon dioxide aerogel with low density and large specific surface area at ordinary pressure |
| CN104030301A (en) * | 2014-06-18 | 2014-09-10 | 金承黎 | Silicon dioxide aerogel material and preparation method thereof |
| CN105621419A (en) * | 2014-12-02 | 2016-06-01 | 北京建工新型建材有限责任公司 | Ambient preparation method for silica aerogel powder |
| CN106082243A (en) * | 2016-06-12 | 2016-11-09 | 伊科纳诺（北京）科技发展有限公司 | A kind of normal pressure fast preparation method of hydrophobic silica aerogel powder body |
-
2017
- 2017-03-22 CN CN201710172205.1A patent/CN106865558A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101244826A (en) * | 2008-03-20 | 2008-08-20 | 绍兴纳诺气凝胶新材料研发中心有限公司 | Method for producing silicon dioxide silica aerogel by drying in atmosphere pressure with rice hull as raw material |
| CN101259964A (en) * | 2008-03-20 | 2008-09-10 | 绍兴纳诺气凝胶新材料研发中心有限公司 | Constant pressure and dry preparation method for high-performance silicon dioxide aerogel by using rice husk ash as raw material |
| CN102557052A (en) * | 2012-03-05 | 2012-07-11 | 中国科学院上海硅酸盐研究所 | Method for rapidly preparing low-density silicon oxide aerogel |
| CN102765725A (en) * | 2012-08-10 | 2012-11-07 | 蓝烟（北京）科技有限公司 | Method for preparing hydrophobic silica aerogel with low cost |
| CN103818912A (en) * | 2014-01-21 | 2014-05-28 | 合肥科斯孚安全科技有限公司 | Method for preparing silicon dioxide aerogel with low density and large specific surface area at ordinary pressure |
| CN104030301A (en) * | 2014-06-18 | 2014-09-10 | 金承黎 | Silicon dioxide aerogel material and preparation method thereof |
| CN105621419A (en) * | 2014-12-02 | 2016-06-01 | 北京建工新型建材有限责任公司 | Ambient preparation method for silica aerogel powder |
| CN106082243A (en) * | 2016-06-12 | 2016-11-09 | 伊科纳诺（北京）科技发展有限公司 | A kind of normal pressure fast preparation method of hydrophobic silica aerogel powder body |
Non-Patent Citations (4)
| Title |
|---|
| 刘红霞等: "疏水Si02气凝胶的常压制备及在建筑隔热涂料中的应用", 《涂料工业》 * |
| 崔学军等: "甲基三甲氧基硅烷改性工业硅溶胶的工艺及其机理", 《材料科学与工程学报》 * |
| 米歇尔.安德烈.埃杰尔特等: "《气凝胶手册》", 31 December 2014, 中国原子能出版社 * |
| 苏家齐: "《塑料工业辞典》", 31 December 1989 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108147415A (en) * | 2018-01-04 | 2018-06-12 | 中国科学技术大学 | A kind of preparation method of silica aerogel material |
| CN110386607A (en) * | 2018-04-19 | 2019-10-29 | 卢序 | The preparation method of aeroge |
| CN108793173B (en) * | 2018-08-01 | 2020-05-05 | 中国科学技术大学 | Method for preparing modified silica aerogel material by adopting external circulation mode and normal pressure drying |
| CN108793173A (en) * | 2018-08-01 | 2018-11-13 | 中国科学技术大学 | A method of improved silica aerogel material is prepared using outer circulation mode constant pressure and dry |
| CN109046190A (en) * | 2018-09-27 | 2018-12-21 | 广东工业大学 | A kind of pectin dioxide composite silica aerogel and the preparation method and application thereof |
| CN109467094A (en) * | 2018-12-25 | 2019-03-15 | 安徽确成硅化学有限公司 | A kind of preparation method preparing functional white carbon black using the leaf of bamboo |
| CN110590014A (en) * | 2019-09-17 | 2019-12-20 | 济南大学 | Method for purifying electroplating wastewater and application of obtained xerogel in glass |
| CN111304910A (en) * | 2020-02-14 | 2020-06-19 | 中南大学 | Ceramic fiber/hydrophobic silicon dioxide aerogel composite material and preparation method thereof |
| WO2023009065A3 (en) * | 2021-07-27 | 2023-04-13 | Singapore Polytechnic | Method for making silica aerogel blanket |
| CN114122397A (en) * | 2021-10-12 | 2022-03-01 | 湖南金硅科技有限公司 | Carbon nanotube-connected dual-carbon-layer-coated mesoporous silica composite material and preparation method and application thereof |
| CN114122397B (en) * | 2021-10-12 | 2023-11-10 | 湖南金硅科技有限公司 | Carbon nanotube-connected double-carbon-layer-coated mesoporous silica composite material and preparation method and application thereof |
| CN114538454A (en) * | 2022-01-28 | 2022-05-27 | 江苏安珈新材料科技有限公司 | Method for preparing silica aerogel by using alkaline silica sol |
| WO2023226710A1 (en) * | 2022-05-27 | 2023-11-30 | 中化学华陆新材料有限公司 | Method for preparing silicon dioxide aerogel or composite product thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106865558A (en) | Normal pressure prepares the method and obtained aerosil of aerosil | |
| WO2018049965A1 (en) | Method for quickly preparing aerogel by using microemulsion as precursor | |
| CN101503195B (en) | Method for preparing hydrophobic SiO2 aerogel | |
| CN101456569B (en) | Method for quickly preparing aerogel by hydro-thermal synthesis at low cost | |
| CN102674374B (en) | Preparation method of silica aerogel | |
| CN102642842B (en) | Method for preparing silicon dioxide aerogel by using acidic silica sol | |
| CN106745004A (en) | A kind of quick method for preparing hydrophobic silica aerogel of low cost | |
| CN103435055A (en) | Method for preparing low density silica aerogel under normal pressure | |
| CN106867019A (en) | One kettle way prepares SiO2The method of cellulose composite aerogel material | |
| CN102659120A (en) | Preparation method for hydrophobic large-size bulk nanometer porous SiO2 aerogel | |
| CN105344334B (en) | A kind of preparation method of polyvinyl alcohol/silicon dioxide complex microsphere | |
| CN109019612B (en) | Rare earth toughened silicon solid silicon aerogel | |
| CN111017934B (en) | Bioactive silicon regenerative medical material and preparation method thereof | |
| CN106395837A (en) | Method for preparing silicon dioxide aerogel | |
| CN104909375A (en) | Method for rapidly preparing hydrophobicsilica aerogel by carbon dioxidesubcritical drying method | |
| CN102091589A (en) | SiO2-WO3 composite aerogel and preparation method thereof | |
| CN106185965A (en) | The method preparing hollow silicic acid nickel microsphere for template with silicon dioxide | |
| CN1278933C (en) | Method for preparing silicon dioxide aerogel by normal pressure drying method using rice hull ash as raw material | |
| WO2018170772A1 (en) | Method for preparing silicon dioxide aerogel at atmospheric pressure and prepared silicon dioxide aerogel | |
| KR20130126215A (en) | Solvent for the preparation of aerogel and method for preparing hydrophobic aerogel by using the same | |
| CN104876226A (en) | Method for rapidly preparing hydrophobic silica aerogel through subcritical drying of methanol | |
| CN101289191B (en) | Transparent meso-porousearth silicon gel monolithi material | |
| CN108147415A (en) | A kind of preparation method of silica aerogel material | |
| CN109020470A (en) | A kind of method that constant pressure and dry prepares aeroge complex heat-preservation felt | |
| CN107128933A (en) | A kind of supercritical drying preparation method of aerosil heat-barrier material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20170620 |
|
| RJ01 | Rejection of invention patent application after publication |