CN111647192A - Chemical crosslinking type polyimide aerogel and preparation method thereof - Google Patents
Chemical crosslinking type polyimide aerogel and preparation method thereof Download PDFInfo
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- CN111647192A CN111647192A CN202010485678.9A CN202010485678A CN111647192A CN 111647192 A CN111647192 A CN 111647192A CN 202010485678 A CN202010485678 A CN 202010485678A CN 111647192 A CN111647192 A CN 111647192A
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- 239000004964 aerogel Substances 0.000 title claims abstract description 125
- 238000010382 chemical cross-linking Methods 0.000 title claims abstract description 92
- 239000004642 Polyimide Substances 0.000 title claims abstract description 90
- 229920001721 polyimide Polymers 0.000 title claims abstract description 90
- 238000002360 preparation method Methods 0.000 title claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 45
- 239000000463 material Substances 0.000 claims abstract description 12
- 229920005575 poly(amic acid) Polymers 0.000 claims description 72
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- 239000000017 hydrogel Substances 0.000 claims description 45
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- DDXLVDQZPFLQMZ-UHFFFAOYSA-M dodecyl(trimethyl)azanium;chloride Chemical compound [Cl-].CCCCCCCCCCCC[N+](C)(C)C DDXLVDQZPFLQMZ-UHFFFAOYSA-M 0.000 claims description 15
- -1 alkyl ammonium halide Chemical class 0.000 claims description 14
- JTTIOYHBNXDJOD-UHFFFAOYSA-N 2,4,6-triaminopyrimidine Chemical compound NC1=CC(N)=NC(N)=N1 JTTIOYHBNXDJOD-UHFFFAOYSA-N 0.000 claims description 13
- GTDPSWPPOUPBNX-UHFFFAOYSA-N ac1mqpva Chemical compound CC12C(=O)OC(=O)C1(C)C1(C)C2(C)C(=O)OC1=O GTDPSWPPOUPBNX-UHFFFAOYSA-N 0.000 claims description 13
- 150000004985 diamines Chemical class 0.000 claims description 13
- 150000003512 tertiary amines Chemical class 0.000 claims description 12
- HLBLWEWZXPIGSM-UHFFFAOYSA-N 4-Aminophenyl ether Chemical compound C1=CC(N)=CC=C1OC1=CC=C(N)C=C1 HLBLWEWZXPIGSM-UHFFFAOYSA-N 0.000 claims description 10
- 230000032683 aging Effects 0.000 claims description 6
- VQVIHDPBMFABCQ-UHFFFAOYSA-N 5-(1,3-dioxo-2-benzofuran-5-carbonyl)-2-benzofuran-1,3-dione Chemical compound C1=C2C(=O)OC(=O)C2=CC(C(C=2C=C3C(=O)OC(=O)C3=CC=2)=O)=C1 VQVIHDPBMFABCQ-UHFFFAOYSA-N 0.000 claims description 5
- 239000011148 porous material Substances 0.000 claims description 5
- CBCKQZAAMUWICA-UHFFFAOYSA-N 1,4-phenylenediamine Chemical compound NC1=CC=C(N)C=C1 CBCKQZAAMUWICA-UHFFFAOYSA-N 0.000 claims description 3
- UDQLIWBWHVOIIF-UHFFFAOYSA-N 3-phenylbenzene-1,2-diamine Chemical compound NC1=CC=CC(C=2C=CC=CC=2)=C1N UDQLIWBWHVOIIF-UHFFFAOYSA-N 0.000 claims description 3
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims description 3
- 229920000877 Melamine resin Polymers 0.000 claims description 3
- UEEJHVSXFDXPFK-UHFFFAOYSA-O N-dimethylethanolamine Chemical compound C[NH+](C)CCO UEEJHVSXFDXPFK-UHFFFAOYSA-O 0.000 claims description 3
- WOWHHFRSBJGXCM-UHFFFAOYSA-M cetyltrimethylammonium chloride Chemical compound [Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)C WOWHHFRSBJGXCM-UHFFFAOYSA-M 0.000 claims description 3
- 238000007872 degassing Methods 0.000 claims description 3
- 230000018044 dehydration Effects 0.000 claims description 3
- 238000006297 dehydration reaction Methods 0.000 claims description 3
- XJWSAJYUBXQQDR-UHFFFAOYSA-M dodecyltrimethylammonium bromide Chemical compound [Br-].CCCCCCCCCCCC[N+](C)(C)C XJWSAJYUBXQQDR-UHFFFAOYSA-M 0.000 claims description 3
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims description 3
- 238000007363 ring formation reaction Methods 0.000 claims description 3
- YFTHZRPMJXBUME-UHFFFAOYSA-N tripropylamine Chemical compound CCCN(CCC)CCC YFTHZRPMJXBUME-UHFFFAOYSA-N 0.000 claims description 3
- 238000001291 vacuum drying Methods 0.000 claims description 3
- BFSVOASYOCHEOV-UHFFFAOYSA-N 2-diethylaminoethanol Chemical compound CCN(CC)CCO BFSVOASYOCHEOV-UHFFFAOYSA-N 0.000 claims description 2
- 239000003431 cross linking reagent Substances 0.000 claims description 2
- ANSXAPJVJOKRDJ-UHFFFAOYSA-N furo[3,4-f][2]benzofuran-1,3,5,7-tetrone Chemical compound C1=C2C(=O)OC(=O)C2=CC2=C1C(=O)OC2=O ANSXAPJVJOKRDJ-UHFFFAOYSA-N 0.000 claims description 2
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- VLDPXPPHXDGHEW-UHFFFAOYSA-N 1-chloro-2-dichlorophosphoryloxybenzene Chemical compound ClC1=CC=CC=C1OP(Cl)(Cl)=O VLDPXPPHXDGHEW-UHFFFAOYSA-N 0.000 description 13
- 239000008367 deionised water Substances 0.000 description 13
- 229910021641 deionized water Inorganic materials 0.000 description 13
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- WUPRYUDHUFLKFL-UHFFFAOYSA-N 4-[3-(4-aminophenoxy)phenoxy]aniline Chemical compound C1=CC(N)=CC=C1OC1=CC=CC(OC=2C=CC(N)=CC=2)=C1 WUPRYUDHUFLKFL-UHFFFAOYSA-N 0.000 description 5
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- QHHKLPCQTTWFSS-UHFFFAOYSA-N 5-[2-(1,3-dioxo-2-benzofuran-5-yl)-1,1,1,3,3,3-hexafluoropropan-2-yl]-2-benzofuran-1,3-dione Chemical compound C1=C2C(=O)OC(=O)C2=CC(C(C=2C=C3C(=O)OC(=O)C3=CC=2)(C(F)(F)F)C(F)(F)F)=C1 QHHKLPCQTTWFSS-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
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- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/28—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/24—Crosslinking, e.g. vulcanising, of macromolecules
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2201/00—Foams characterised by the foaming process
- C08J2201/04—Foams characterised by the foaming process characterised by the elimination of a liquid or solid component, e.g. precipitation, leaching out, evaporation
- C08J2201/048—Elimination of a frozen liquid phase
- C08J2201/0484—Elimination of a frozen liquid phase the liquid phase being aqueous
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2205/00—Foams characterised by their properties
- C08J2205/02—Foams characterised by their properties the finished foam itself being a gel or a gel being temporarily formed when processing the foamable composition
- C08J2205/026—Aerogel, i.e. a supercritically dried gel
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2379/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen, or carbon only, not provided for in groups C08J2361/00 - C08J2377/00
- C08J2379/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
- C08J2379/08—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
Abstract
The invention discloses a chemical crosslinking type polyimide aerogel and a preparation method thereof, belonging to the technical field of materials. The method has the advantages of simplicity, high efficiency, low equipment requirement, wide application range and environmental friendliness, can effectively avoid the problem that the traditional polyimide high-performance aerogel is difficult to prepare, can be used for gas adsorption, organic matter adsorption, heat insulation materials and the like, and has high potential application value in the fields of air pollution treatment, water pollution treatment, heat insulation structural materials and the like.
Description
Technical Field
The invention belongs to the technical field of materials, relates to preparation of polymer aerogel, and particularly relates to chemical crosslinking type polyimide aerogel and a preparation method thereof.
Background
Aerogel is a highly dispersed solid material, mainly composed of a nanoporous network structure with pores obtained by aggregation of colloidal particles (or polymer molecules) filled with gaseous dispersion medium, usually prepared by wet gel, and is a three-dimensional porous nanomaterial in which the liquid component is replaced by gas during drying of wet gel and the gel network is still maintained. The special continuous three-dimensional network structure enables the aerogel to show unique properties in the aspects of heat, mechanics, acoustics, optics, electricity and the like, so that the aerogel attracts attention in the fields of separation materials, adsorption materials, heat insulation materials, gas and biological sensors, low dielectric constant materials and the like.
Polyimide is a polymer containing imide rings in a molecular main chain structural unit, has extremely outstanding thermal oxygen stability, dielectric property, environmental aging resistance, radiation resistance, chemical solvent resistance, mechanical strength and the like, is one of polymer materials with the best comprehensive performance at present, and is also one of ideal materials for preparing polymer aerogel. The polyimide aerogel is prepared by the following method: firstly, preparing polyamic acid (polyimide precursor) from dianhydride and diamine monomers; then, chemical imidization is to convert the polyamic acid solution into polyimide gel; finally, the polyimide gel is placed in supercritical CO2Drying to obtain the aerogel. However, this method requires high polyimide solubility, and requires soluble polyimide to prepare polyimide gel, which results in that most insoluble polyimides cannot be used to prepare aerogel by this method. In recent years, a method of using tertiary amine to assist a water-soluble polyimide precursor (polyamic acid) provides a new idea for preparing polyimide aerogel, namely, the polyamic acid aerogel is prepared by a polyamic acid hydrogel freeze-drying method and then is subjected to thermal imidization to obtain the polyimide aerogel. The method is simple and efficient, is suitable for preparing most of polyimide aerogel, and is an ideal polyimide aerogel preparation method. However, the polyamic acid aerogel has a large molecular chain flexibility and a low aerogel skeleton strength, which causes large size shrinkage of the polyamic acid aerogel, and further seriously affects the quality of the polyimide aerogel product. Generally, chemical cross-linking is introducedThe linked structure is an effective means for polymer enhancement, but because the carboxylate activity on the molecular chain of the polyamic acid is lower, the polyamic acid cannot be further crosslinked with a polyamine monomer in an aqueous solution system, and the polyamic acid after chemical crosslinking is difficult to dissolve in water under the action of tertiary amine, so that the application of the enhanced mode of chemical crosslinking in the preparation of polyimide aerogel by a freeze-drying method is limited to a certain extent. A method for directly preparing polyamic acid hydrogel in aqueous solution system makes it possible to introduce a chemical crosslinking structure. On the basis, the polyamide acid aerogel skeleton strength can be effectively increased by introducing a branched structure into a polyamide acid system through a polyamine monomer, so that the size shrinkage of the polyamide acid aerogel skeleton is effectively reduced, and the polyamide acid aerogel skeleton strength has great significance for preparation of polyimide aerogel.
Disclosure of Invention
The invention provides a chemical crosslinking type polyimide aerogel and a preparation method thereof, aiming at solving the problems in the prior art, the method is a simple and efficient chemical crosslinking type polyimide aerogel preparation method with low equipment requirement and wide application range, namely, the chemical crosslinking type polyamide acid hydrogel is directly prepared in an aqueous solution system by dianhydride, diamine and polyamine under the action of tertiary amine and alkyl ammonium halide compounds, and the chemical crosslinking type polyimide aerogel is obtained by freeze drying and thermal imidization.
In order to achieve the purpose, the invention adopts the following technical means:
a preparation method of a chemical crosslinking type polyimide aerogel comprises the following steps:
diamine monomer and dianhydride monomer are used as raw materials, polyamine is used as a cross-linking agent, tertiary amine is used as a dissolving aid, alkyl ammonium halide is used as a surfactant, water is used as a medium, and after all the materials are mixed, the mixture is stirred and reacts at room temperature or under the ice-water bath condition to prepare the chemical cross-linking type polyamic acid hydrogel; wherein the addition molar ratio of the diamine monomer to the polyamine monomer to the dianhydride monomer is (0.95-1.05): (0.01-0.20): 1;
vacuum degassing the chemical crosslinking type polyamic acid hydrogel, refrigerating, aging, and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel;
and (3) carrying out thermal imidization on the chemical crosslinking type polyamic acid aerogel to carry out dehydration cyclization, thus obtaining the chemical crosslinking type polyimide aerogel.
As a further improvement of the invention, the diamine monomer is one or a mixture of more than one of commercially available 4,4' -diaminodiphenyl ether, biphenyldiamine and p-phenylenediamine in any proportion.
As a further improvement of the invention, the dianhydride monomer is one or a mixture of more of pyromellitic anhydride, hexafluoro dianhydride and 3,3 ', 4,4' -benzophenonetetracarboxylic dianhydride in any proportion.
As a further improvement of the invention, the polyamine is one or a mixture of several of 2,4, 6-triaminopyrimidine, 2,6, 14-triaminotriptycene and melamine in any proportion.
As a further improvement of the invention, the tertiary amine is one or a mixture of several of triethylamine, tripropylamine, N-dimethylethanolamine and N, N-diethylethanolamine in any proportion.
As a further improvement of the invention, the alkyl ammonium halide is one or a mixture of several of dodecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride, dodecyl trimethyl ammonium bromide and hexadecyl trimethyl ammonium bromide in any proportion.
As a further improvement of the invention, the specific method for refrigerating and aging after vacuum degassing comprises the following steps: degassing in a vacuum drying oven for 2-6 hours, and then putting in a refrigerating chamber of a refrigerator for refrigerating for 2-3 days.
As a further improvement of the invention, the freeze drying refers to that the chemical crosslinking type polyamic acid hydrogel is placed in a freezing chamber of a refrigerator and is frozen until the solution is completely frozen; the freeze-drying conditions were: the temperature is less than or equal to-50 ℃; the pressure is less than or equal to 20Pa, and the time is as follows: 12-48 h.
As a further improvement of the present invention, the thermal imidization treatment temperature is: the treatment time is 0.5-2 h at 120 ℃, 0.5-2 h at 150 ℃, 0.5-2 h at 200 ℃, 0.5-2 h at 250 ℃, 0.5-2 h at 300 ℃ and 0.5-2 h at 350 ℃.
According to the chemical crosslinking type polyimide aerogel prepared by the preparation method, the polyimide aerogel framework is of a sheet-shaped porous structure, and the pore diameter of the porous structure is ten micrometers to two hundred micrometers.
Compared with the prior art, the invention has the following advantages:
the preparation method of the chemical crosslinking type polyimide aerogel comprises the steps of reacting a diamine monomer, a dianhydride monomer, a polyamine monomer, a tertiary amine and alkyl ammonium halide in an aqueous solution to prepare a chemical crosslinking type polyamic acid hydrogel, placing the obtained polyamic acid hydrogel in a mold, vacuum degassing, refrigerating and aging, and finally carrying out freeze drying and thermal imidization on the polyamic acid hydrogel to prepare the chemical crosslinking type polyimide aerogel.
Experiments show that the introduction of the chemical crosslinking structure into the polyamic acid aqueous solution system can increase the strength of a gel framework, effectively reduce the size shrinkage rate of the polyimide aerogel and obviously improve the quality of a polyimide aerogel product. The method has the advantages that the chemical crosslinking type polyamic acid hydrogel is directly prepared through the combined action of the tertiary amine and the alkyl ammonium halide, the method is suitable for the preparation of different types of chemical crosslinking type polyimide aerogel, and the dissolving performance of polyimide is not required to be considered; meanwhile, hydrogel freeze drying is simple and easy to implement, and the requirement on equipment is low. Therefore, the preparation method is widely applicable to preparation of various chemical crosslinking type polyimide aerogels, and can expand the application of the polyimide aerogels in the fields of separation materials, adsorption materials, heat-insulating materials, gas and biosensors, low dielectric constant materials and the like.
Drawings
FIG. 1 is an IR spectrum of a chemically crosslinked polyimide aerogel obtained in example 10;
FIG. 2 shows an optical photograph of the chemically crosslinked polyimide aerogel obtained in example 10 on the right, and an optical photograph of a polyimide aerogel obtained without adding a polyamine under the same conditions on the left;
FIG. 3 is SEM images (a), b) and c) of the chemically crosslinked polyimide aerogel prepared in example 10 at magnifications of × 80, × 200 and × 500), respectively.
Detailed Description
The invention relates to a preparation method of a chemical crosslinking type polyimide aerogel, which specifically comprises the following steps:
firstly, diamine monomer, dianhydride monomer, polyamine monomer, tertiary amine and alkyl ammonium halide react in aqueous solution to prepare the chemical crosslinking type polyamic acid hydrogel.
The specific means is as follows: and (3) carrying out ultrasonic treatment on the single-neck flask, the beaker, the mold, the magneton and the like by using absolute ethyl alcohol, removing surface impurities, and drying for later use. Placing weighed diamine monomer, polyamine monomer, tertiary amine and alkyl ammonium halide into a single-neck flask with a magneton, adding deionized water, stirring at room temperature or under an ice-water bath condition to form a uniform solution, then adding dianhydride monomer, and stirring for 24-48 hours at room temperature or under an ice-water bath condition to form a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel.
Secondly, the obtained polyamic acid hydrogel is placed in a mold, is subjected to vacuum degassing and then is refrigerated and aged for 2 to 3 days.
The specific means is as follows: pouring the prepared chemical crosslinking type polyamic acid hydrogel into a mold, degassing in a vacuum drying oven for 2-6 h, and then putting the mold into a refrigerator for refrigerating for 2-3 days.
And finally, preparing the chemical crosslinking polyimide aerogel from the polyamic acid hydrogel through freeze drying and thermal imidization processes.
The specific means is as follows: placing the refrigerated chemical crosslinking type polyamic acid hydrogel in a freezing chamber of a refrigerator, and freezing until the solution is completely frozen; and (3) freezing and drying the frozen polyamic acid hydrogel sample to obtain the chemical crosslinking type polyamic acid composite aerogel, and carrying out heat treatment to dehydrate and cyclize the polyamic acid to obtain the chemical crosslinking type polyimide aerogel.
Wherein, the dehydration and cyclization process of the polyamic acid aerogel adopts step temperature, and the temperature range is 120-350 ℃. Comprehensively considering, the polyamide acid thermal imidization mechanism and the morphology and performance of the aerogel, and the optimal polyamide acid aerogel thermal imidization process comprises the following steps: 120 ℃ (0.5-2 h) +150 ℃ (0.5-2 h) +200 ℃ (0.5-2 h) +250 ℃ (0.5-2 h) +300 ℃ (0.5-2 h) +350 ℃ (0.5-2 h).
The diamine monomer is one or a mixture of more of commercially available 4,4' -diaminodiphenyl ether, biphenyldiamine, p-phenylenediamine and the like in any proportion. The dianhydride monomer is one or a mixture of a plurality of commercially available pyromellitic dianhydride, hexafluoro dianhydride, 3 ', 4,4' -benzophenone tetracarboxylic dianhydride and the like in any proportion.
The polyamine is one or a mixture of more of 2,4, 6-triaminopyrimidine, 2,6, 14-triaminotriptycene, melamine and the like in any proportion. The addition molar ratio of the diamine monomer to the polyamine monomer to the dianhydride monomer is (0.95-1.05): (0.01-0.20): 1.
the tertiary amine is one or a mixture of more of triethylamine, tripropylamine, N-dimethylethanolamine, N-diethylethanolamine and the like in any proportion. The alkyl ammonium halide is one or a mixture of several of dodecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride, dodecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium bromide and the like in any proportion.
The mold may be any container, preferably a beaker or other type of glass article, and the like.
According to the chemical crosslinking type polyimide aerogel prepared by the preparation method, the polyimide aerogel framework is of a sheet-shaped porous structure, and the pore diameter of the porous structure is ten micrometers to two hundred micrometers.
The technical scheme of the invention is explained in detail by combining the specific embodiment and the attached drawings as follows:
example 1
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.00g of 4,4' -diaminodiphenyl ether (ODA), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (0.5h) +250 ℃ (0.5h) +300 ℃ (0.5h) +350 ℃ (2 h).
Example 2
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 1.90g of 4,4' -diaminodiphenyl ether (ODA), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (2h) +150 ℃ (2h) +200 ℃ (2h) +250 ℃ (2h) +300 ℃ (2h) +350 ℃ (0.5 h).
Example 3
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.10g of 4,4' -diaminodiphenyl ether (ODA), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Example 4
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.00g of 4,4' -diaminodiphenyl ether (ODA), 0.25g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Example 5
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.00g of 4,4' -diaminodiphenyl ether (ODA), 0.01g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Example 6
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.92g of 1, 3-bis (4-aminophenoxy) benzene (BAPB), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 2.18g of pyromellitic dianhydride (PMDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Example 7
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.00g of 4,4 '-diaminodiphenyl ether (ODA), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 4.44g of 4,4' - (hexafluoro isopropyl) diphthalic anhydride (6FDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Example 8
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.92g of 1, 3-bis (4-aminophenoxy) benzene (BAPB), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 3.22g of 3,3 ', 4,4' - -Benzophenone Tetracarboxylic Dianhydride (BTDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (2h) +150 ℃ (2h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (0.5h) +350 ℃ (0.5 h).
Example 9
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.92g of 1, 3-bis (4-aminophenoxy) benzene (BAPB), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 4.44g of 4,4' - (hexafluoro-isopropylene) diphthalic anhydride (6FDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (1h) +150 ℃ (1h) +200 ℃ (2h) +250 ℃ (2h) +300 ℃ (2h) +350 ℃ (2 h).
Example 10
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.00g of 4,4' -diaminodiphenyl ether (ODA), 0.06g of 2,4, 6-triaminopyrimidine, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 3.22g of 3,3 ', 4,4' -Benzophenone Tetracarboxylic Dianhydride (BTDA) and continuously stirring for 24 hours to obtain viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (0.5h) +150 ℃ (0.5h) +200 ℃ (1h) +250 ℃ (1h) +300 ℃ (1h) +350 ℃ (1 h).
Fig. 1 is an infrared spectrum of the chemically crosslinked polyimide aerogel in example 10, and the occurrence of an infrared characteristic peak verifies the successful preparation of the polyimide aerogel.
Fig. 2 shows an optical photograph of the chemical crosslinking type polyimide aerogel in example 10 on the right, and an optical photograph of the polyimide aerogel prepared without adding polyamine under the same conditions on the left, which shows that the size shrinkage of the polyimide aerogel can be effectively reduced by introducing a crosslinking structure between polyimide molecular chains through polyamine.
Fig. 3 is SEM images a), b), and c) of the chemically cross-linked polyimide aerogel prepared in example 10 at magnifications of × 80, × 200, and × 500), respectively, and it can be seen that the prepared polyimide aerogel framework has a sheet-like porous structure with pore diameters varying from tens of micrometers to two hundred micrometers.
Example 11
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.92g of 1, 3-bis (4-aminophenoxy) benzene (BAPB), 0.08g of 2,6, 14-triaminotriptycene, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 4.44g of 4,4' - (hexafluoroisopropylidene) diphthalic anhydride (6FDA) and continuously stirring for 24 hours to obtain viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (2h) +150 ℃ (2h) +200 ℃ (2h) +250 ℃ (0.5h) +300 ℃ (0.5h) +350 ℃ (0.5 h).
Example 12
Preparing a chemical crosslinking type polyimide aerogel: firstly, adding 2.92g of 1, 3-bis (4-aminophenoxy) benzene (BAPB), 0.08g of 2,6, 14-triaminotriptycene, 0.1mL of triethylamine and 0.1g of dodecyl trimethyl ammonium chloride into 50mL of deionized water, stirring under the condition of ice-water bath until a uniform solution is formed, adding 3.22g of 3,3 ', 4,4' - -Benzophenone Tetracarboxylic Dianhydride (BTDA) and continuously stirring for 24 hours to obtain a viscous liquid, namely the chemical crosslinking type polyamic acid hydrogel; secondly, pouring the hydrogel into a mold, refrigerating for 48 hours after vacuum degassing, and then freezing and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel; and finally, carrying out thermal imidization treatment on the obtained polyamic acid aerogel to obtain the chemical crosslinking polyimide aerogel, wherein the thermal imidization process comprises the following steps: 120 ℃ (2h) +150 ℃ (2h) +200 ℃ (0.5h) +250 ℃ (0.5h) +300 ℃ (0.5h) +350 ℃ (0.5 h).
The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention.
Claims (10)
1. A preparation method of a chemical crosslinking type polyimide aerogel is characterized by comprising the following steps:
diamine monomer and dianhydride monomer are used as raw materials, polyamine is used as a cross-linking agent, tertiary amine is used as a dissolving aid, alkyl ammonium halide is used as a surfactant, water is used as a medium, and after all the materials are mixed, the mixture is stirred and reacts at room temperature or under the ice-water bath condition to prepare the chemical cross-linking type polyamic acid hydrogel; wherein the addition molar ratio of the diamine monomer to the polyamine monomer to the dianhydride monomer is (0.95-1.05): (0.01-0.20): 1;
vacuum degassing the chemical crosslinking type polyamic acid hydrogel, refrigerating, aging, and freeze-drying to obtain the chemical crosslinking type polyamic acid aerogel;
and (3) carrying out thermal imidization on the chemical crosslinking type polyamic acid aerogel to carry out dehydration cyclization, thus obtaining the chemical crosslinking type polyimide aerogel.
2. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the diamine monomer is one or a mixture of more of commercially available 4,4' -diaminodiphenyl ether, biphenyldiamine and p-phenylenediamine in any proportion.
3. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the dianhydride monomer is one or a mixture of more of pyromellitic anhydride, hexafluoro dianhydride and 3,3 ', 4,4' -benzophenone tetracarboxylic dianhydride in any proportion.
4. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the polyamine is one or a mixture of more of 2,4, 6-triaminopyrimidine, 2,6, 14-triaminotriptycene and melamine in any proportion.
5. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the tertiary amine is one or a mixture of more of triethylamine, tripropylamine, N-dimethylethanolamine and N, N-diethylethanolamine in any proportion.
6. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the alkyl ammonium halide is one or a mixture of several of dodecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride, dodecyl trimethyl ammonium bromide and hexadecyl trimethyl ammonium bromide in any proportion.
7. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the specific method for refrigerating and aging after vacuum degassing comprises the following steps: degassing in a vacuum drying oven for 2-6 hours, and then putting in a refrigerating chamber of a refrigerator for refrigerating for 2-3 days.
8. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the freeze drying refers to that the chemical crosslinking type polyamic acid hydrogel is placed in a freezing chamber of a refrigerator and is frozen until the solution is completely frozen; the freeze-drying conditions were: the temperature is less than or equal to-50 ℃; the pressure is less than or equal to 20Pa, and the time is as follows: 12-48 h.
9. The method for preparing the chemically cross-linked polyimide aerogel according to claim 1, wherein the method comprises the following steps: the thermal imidization treatment temperature is as follows: the treatment time is 0.5-2 h at 120 ℃, 0.5-2 h at 150 ℃, 0.5-2 h at 200 ℃, 0.5-2 h at 250 ℃, 0.5-2 h at 300 ℃ and 0.5-2 h at 350 ℃.
10. The chemically crosslinked polyimide aerogel produced by the production method according to any one of claims 1 to 9, characterized in that: the polyimide aerogel framework is of a sheet-shaped porous structure, and the pore diameter of the porous structure is ten micrometers to two hundred micrometers.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105968354A (en) * | 2016-05-30 | 2016-09-28 | 南京工业大学 | Preparation method of polyimide aerogel for CO2 adsorption |
| CN107337797A (en) * | 2017-07-01 | 2017-11-10 | 中国科学院兰州化学物理研究所 | A kind of preparation method of crosslinked polyimide aeroge |
| CN110606979A (en) * | 2019-09-23 | 2019-12-24 | 陕西科技大学 | Green preparation method of polyimide aerogel |
-
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105968354A (en) * | 2016-05-30 | 2016-09-28 | 南京工业大学 | Preparation method of polyimide aerogel for CO2 adsorption |
| CN107337797A (en) * | 2017-07-01 | 2017-11-10 | 中国科学院兰州化学物理研究所 | A kind of preparation method of crosslinked polyimide aeroge |
| CN110606979A (en) * | 2019-09-23 | 2019-12-24 | 陕西科技大学 | Green preparation method of polyimide aerogel |
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|---|---|---|---|---|
| CN115537026A (en) * | 2022-09-22 | 2022-12-30 | 中国人民解放军军事科学院系统工程研究院 | Polyimide aerogel and preparation method thereof |
| CN115537026B (en) * | 2022-09-22 | 2024-01-16 | 中国人民解放军军事科学院系统工程研究院 | Polyimide aerogel and preparation method thereof |
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