CN102417604A - Preparation method of polyimide porous film - Google Patents
Preparation method of polyimide porous film Download PDFInfo
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- CN102417604A CN102417604A CN 201010297037 CN201010297037A CN102417604A CN 102417604 A CN102417604 A CN 102417604A CN 201010297037 CN201010297037 CN 201010297037 CN 201010297037 A CN201010297037 A CN 201010297037A CN 102417604 A CN102417604 A CN 102417604A
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Abstract
The invention discloses a preparation method of a polyimide porous film. According to the invention, silica colloid ball is used as a template; uniformly dispersed polyamide acids (PAA) / SiO2 colloidal solution is dried to obtain a PAA / SiO2 composite film with an ordered structure; the composite film is treated with thermal imidization, etched by a hydrofluoric acid solution to remove the SiO2 colloid ball, washed and dried in vacuum to obtain the polyimide porous film with an ordered structure. The invention is simply operated, at low cost and easy for industrialized production; the prepared polyimide porous material has advantages of ordered structure, ordered aperture, large strength and heat resistance, etc.
Description
Technical field
The present invention relates to a kind of preparation method of polyimide porous membrane, be specifically related to a kind of preparation method structurally ordered, controllable aperture polyimide porous membrane that has.
Background technology
Polyimide porous material; Except that possessed the superior mechanical property of polyimide material, dimensional stability, the solvent resistance; The density that the introducing of hole makes it possess porous material simultaneously is little, specific surface area is big, than characteristics such as mechanics performance are high, damping capacity is good, and it is functional to give light, electricity, magnetic etc. simultaneously for the polyimide porous material of ordered nano-structure.Therefore, polyimide porous material all has a wide range of applications in fields such as catalysis, isolation and purification, biological tissue's reparation, photoelectric device and tribology.Especially microelectronic device application facet, polyimide porous material be because its excellent thermotolerance, mechanical property, dielectric properties and good cementability, is considered to substitute silicon oxide and the electronic component that becomes a new generation connects and the novel material of protection.
At present, preparing polyimide porous material mainly is some traditional methods, like physics or chemical blowing process, solvent-inducedly be separated, powder metallurgy is cold-rolled sintered and add pore-creating agent etc.; Patents such as JP2003201363, US20020058720, CN1562607A, EP1211280A1, CN101638490A disclose aforesaid method.Though these several kinds of traditional method technologies are easier, all have the accurately size of control punch and the shortcoming of distribution, and prepared aperture of porous material is bigger.In order to reduce the size in aperture; Reported in recent years with thermal unstable polymer (PS; PAA and PU etc.) and polyimide copolymerization or grafting; It is the uniform texture of matrix that this analog copolymer takes place under certain condition that micron-scale phase separation forms with the thermal unstable polymer to the disperse phase polyimide, and the method through heating makes thermal unstable polymer be decomposed into low molecular weight product effusion matrix then, thereby in matrix, stays the uniform micro structure.Compare with traditional method, aperture that this method obtains is less, and pore distribution is more even, and can pass through the change of thermal unstable polymer molecular weight and then the pore size of adjusting gained porous material.The shortcoming of this method is in adding heat extraction labile polymer process; The second-order transition temperature that approaches polyimide owing to temperature is too high makes the polyimide plasticizing; The cavity of original formation is subsided and voidage is descended, and because the high temperature cabonization of labile polymer causes film color burn even blackening.
As a kind of simple effective method of preparation porous inorganic material and polymer materials, hard template method prepares polyimide porous material becomes a research focus in recent years.Patent CN1760241A discloses two-step approach and has prepared Nano film of multiporous polyimide: at first, prepare polyimide-aktivton film through sol-gel method; Secondly, the silicon oxide that utilizes hydrofluoric acid will be dispersed in the film is removed, and stays aperture, can make Nano film of multiporous polyimide, and the aperture is 20～120nm.Also have through utilizing ceramic particle to prepare the Kapton of single face vesicular structure as hard template: at first with polyamic acid solution with leave standstill for a long time after ceramic particle mixes; Because the settlement action ceramic particle can be deposited on solution bottom, treat that the imidization of solvent evaporates post-heating removes the Kapton that ceramic particle obtains the single face vesicular structure with hydrofluoric acid dips again.Though these two kinds of methods can prepare cashier hole or macropore polyimide porous material, all have the shortcoming that the aperture is wayward, porosity is low.
Summary of the invention
The objective of the invention is to overcome wayward, the pockety shortcoming in polyimide porous material aperture in the prior art, a kind of preparation method with polyimide porous material of structurally ordered, controllable aperture is provided.
The present invention utilizes silicon-dioxide (SiO
2) the colloid spheres as template, with homodisperse polyamic acid (PAA)/SiO
2The colloidal solution drying obtains having the PAA/SiO of ordered structure
2Laminated film is removed SiO through hydrofluoric acid (HF) solution etching behind the hot imidization
2Colloidal spheres, washing obtains structurally ordered polyimide porous membrane after the vacuum-drying.
A kind of preparation method of polyimide porous membrane, it is characterized in that this method successively step be:
A is with silicon-dioxide (SiO
2) colloidal spheres with contain polyamic acid (PAA) solution and mix, must clarify PAA/SiO after fully disperseing
2Solution; The solvent that wherein contains polyamic acid (PAA) solution is selected from N-2-SL 1332, DMAC N,N and N, a kind of in the dinethylformamide;
B is with PAA/SiO
2Solution is applied on the supporter, and vacuum-drying obtains PAA/SiO
2Hybrid film is heated to 70-400 ℃ then and makes the PAA hot imidization, obtains the polyimide/silicon dioxide hybrid film; Said supporter is selected from a kind of in sheet glass, polyfluortetraethylene plate, stainless steel plate, Copper Foil and the aluminium foil;
C comes off the polyimide/silicon dioxide hybrid film and immerse the hydrofluoric acid aqueous solution etching from supporter and removes SiO
2Colloidal spheres gets structurally ordered polyimide porous membrane after washing, vacuum-drying; Wherein drying temperature is 60～100 ℃, and vacuum tightness is 0.001～0.07 MPa.
Polyamic acid of the present invention is selected from and gathers equal benzene tetramethyl amido acid, gathers the biphenyl tetracarboxylic amido acid and gather a kind of in the benzophenone tetramethyl amido acid.
The mass percentage concentration of said polyamic acid solution of the present invention is 1%～10%.
The particle diameter of silicon dioxide colloid ball of the present invention is 0.1～1.5 micron.
PAA/SiO of the present invention
2In the solution, PAA and SiO
2The mass ratio of colloidal spheres is 100: 30～100.
Hydrofluoric acid aqueous solution mass percentage concentration according to the invention is 5-30%, and etching time is 2-20 hour.
Key of the present invention is the PAA/SiO that obtains having ordered structure through vacuum-drying
2Laminated film, drying temperature are 60～100 ℃, and vacuum tightness is 0.001～0.07 MPa.
The porous polyimide film hole of the present invention's preparation is evenly distributed in order, and pore size is by selecting for use SiO
2The decision of colloidal spheres grain size, the film thickness scope is 5～1000 microns.
The present invention selects the SiO with uniform grading for use
2Colloidal spheres is made hard template, utilizes SiO
2Interaction of hydrogen bond between colloidal spheres surface hydroxyl and the PAA obtains SiO
2Homodisperse PAA/SiO
2Organic solution.Utilize the solvent evaporation abduction mechanism, make PAA/SiO through vacuum drying method
2Organic solution generation self-assembly forms orderly PAA/SiO
2Hybrid film, hot imidization and remove SiO then
2Colloidal spheres makes orderly polyimide porous material;
The present invention is through adjustment SiO
2The colloidal spheres particle diameter can be controlled the aperture of orderly polyimide porous material.
Utilize hard template to prepare the porous polyimide material in the present invention and the prior art and compare, the porous polyimide material hole of preparation is evenly distributed in order controllable aperture; And preparation technology is simple for this method, can carry out fairly large production.
Description of drawings
Fig. 1 is prepared orderly polyimide porous membrane surface and a cross section ESEM picture among the embodiment 1.As shown in the figure, the uniform sequential arrangement of polyimide porous membrane pore structure.
Embodiment
Below in conjunction with specific embodiment, further set forth the present invention, should be understood that these embodiment only be used to the present invention is described and be not used in the restriction scope of the present invention.Should be understood that in addition those skilled in the art can do various changes and modification to the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.
Embodiment 1
(1) select 4 for use, 4 '-diaminodiphenyl oxide and pyromellitic acid anhydride are monomer, N, and dinethylformamide (DMF) prepares heavy-gravity polyamic acid (PAA) solution for solvent.With massfraction is the silicon-dioxide (SiO that 3% PAA solution and particle diameter are 380 nanometers
2) colloidal spheres is according to mass ratio PAA: SiO
2Mix at=7: 3, and ultrasonic agitation obtained settled solution in 3 hours;
(2) with above-mentioned PAA/SiO
2Solution is coated on the sheet glass in 60 ℃ of vacuum-dryings (vacuum tightness: 0.005 MPa) obtain PAA/SiO
2Laminated film; With PAA/SiO
2Laminated film is at 100 ℃, and 200 ℃, 300 ℃ of following each heating keep carrying out imidization in 1 hour and obtain the polyimide/silicon dioxide laminated film;
(3) the polyimide/silicon dioxide laminated film is come off and immerses 10% the HF solution etching from sheet glass remove SiO
2Colloidal spheres obtains structurally ordered porous polyimide film.The orderly polyimide porous membrane of gained porosity is 20%, and SEM Electronic Speculum result shows the film surface aperture: 140 nanometers, inner aperture: 380 nanometers.
Embodiment 2
Method according among the embodiment 1 prepares polyimide porous material, and the massfraction concentration of different is polyamic acid is 6%, SiO
2The mass ratio of colloidal spheres and polyamic acid is 1: 1.The orderly polyimide porous membrane of gained porosity is 40%, and SEM Electronic Speculum result shows the film surface aperture: 140 nanometers, inner aperture: 380 nanometers.
Embodiment 3
Method according among the embodiment 1 prepares polyimide porous material, and that different is the SiO that is selected for use
2The colloidal spheres particle diameter is 1.2 microns, polyamic acid and SiO
2The mass ratio of colloidal spheres is 8: 2, and the orderly polyimide porous membrane of gained porosity is 15%, and SEM Electronic Speculum result shows the film surface aperture: 410 nanometers, inner aperture: 1.1 microns.
Embodiment 4
Method according among the embodiment 1 prepares polyimide porous material, and that different is the SiO that is selected for use
2The colloidal spheres particle diameter is 140 nanometers, polyamic acid and SiO
2The mass ratio of colloidal spheres is 6: 4, and the orderly polyimide porous membrane of gained porosity is 30%, and SEM Electronic Speculum result shows the film surface aperture: 30 nanometers, inner aperture: 135 nanometers.
Embodiment 5
(1) select 4 for use, 4 '-diaminodiphenyl oxide and benzophenone tetracarboxylic dianhydride are that monomer, DMAC N,N (DMAc) prepare heavy-gravity polyamic acid (PAA) solution for solvent.With massfraction is the silicon-dioxide (SiO that 3% PAA solution and particle diameter are 380 nanometers
2) colloidal spheres is according to mass ratio PAA: SiO
2Mix at=6: 4, and ultrasonic agitation obtained settled solution in 3 hours;
(2) with above-mentioned PAA/SiO
2Solution is applied on the sheet glass in 60 ℃ of vacuum-dryings (vacuum tightness: 0.005 MPa) obtain PAA/SiO
2Laminated film; With PAA/SiO
2Laminated film is at 100 ℃, and 200 ℃, 300 ℃ of following each heating keep carrying out an imidization in and obtain the polyimide/silicon dioxide laminated film;
(3) the polyimide/silicon dioxide laminated film that obtains is come off and immerses 10% the HF solution etching from sheet glass remove SiO
2Colloidal spheres obtains structurally ordered porous polyimide film.The orderly polyimide porous membrane of gained porosity is 30%, and SEM Electronic Speculum result shows the film surface aperture: 140 nanometers, inner aperture: 380 nanometers.
Embodiment 6
Method according among the embodiment 4 prepares polyimide porous material, and different is, and to be coated with film support be stainless steel, and the vacuum-drying temperature is 80 ℃; Vacuum tightness is 0.02 MPa, and polyamic acid imidization mode is 100 ℃, 150 ℃; 250 ℃, 300 ℃ each heats maintenance one hour down.The orderly polyimide porous membrane of gained porosity is 20%, and SEM Electronic Speculum result shows the film surface aperture: 140 nanometers, inner aperture: 380 nanometers.
Embodiment 7
(1) selecting Ursol D and bibenzene tetracarboxylic dianhydride for use is that monomer, N-2-SL 1332 (NMP) prepare heavy-gravity polyamic acid (PAA) solution for solvent.With massfraction is the silicon-dioxide (SiO that 3% PAA solution and particle diameter are 750 nanometers
2) colloidal spheres is according to mass ratio PAA: SiO
2Mix at=7: 3, and ultrasonic agitation obtained settled solution in 3 hours;
(2) with above-mentioned PAA/SiO
2Solution is applied on the sheet glass in 100 ℃ of vacuum-dryings (vacuum tightness: 0.01 MPa) obtain PAA/SiO
2Laminated film; With PAA/SiO
2Laminated film is at 150 ℃, and 250 ℃, 350 ℃ of each heating keep carrying out an imidization in and obtain the polyimide/silicon dioxide laminated film;
(3) the polyimide/silicon dioxide laminated film that obtains is come off and immerses 10% the HF solution etching from sheet glass remove SiO
2Colloidal spheres obtains structurally ordered porous polyimide film.The orderly polyimide porous membrane of gained porosity is 20%, and SEM Electronic Speculum result shows the film surface aperture: 260 nanometers, inner aperture: 730 nanometers.
Embodiment 8
Method according among the embodiment 6 prepares polyimide porous material, and different is that PAA liquid quality fraction concentration is 5%, polyamic acid and SiO
2The mass ratio of colloidal spheres is 8: 2, and being coated with film support is polyfluortetraethylene plate, and vacuum tightness is 0.005 MPa during vacuum-drying, and polyamic acid imidization mode is 200 ℃ and 300 ℃, and each heats maintenance 2 hours down.The orderly polyimide porous membrane of gained porosity is 15%, and SEM Electronic Speculum result shows the film surface aperture: 260 nanometers, inner aperture: 730 nanometers.
Claims (6)
1. the preparation method of a polyimide porous membrane, it is characterized in that this method successively step be:
A with the silicon dioxide colloid ball with contain polyamic acid solution and mix, must clarify PAA/SiO after fully disperseing
2Solution; The solvent that wherein contains polyamic acid solution is selected from N-2-SL 1332, DMAC N,N and N, a kind of in the dinethylformamide;
B is with PAA/SiO
2Solution is applied on the supporter, and vacuum-drying obtains PAA/SiO
2Hybrid film is heated to 70-400 ℃ then and makes the PAA hot imidization, obtains the polyimide/silicon dioxide hybrid film; Said supporter is selected from a kind of in sheet glass, polyfluortetraethylene plate, stainless steel plate, Copper Foil and the aluminium foil;
C comes off the polyimide/silicon dioxide hybrid film and immerse the hydrofluoric acid aqueous solution etching from supporter and removes SiO
2Colloidal spheres gets structurally ordered polyimide porous membrane after washing, vacuum-drying; Wherein drying temperature is 60～100 ℃, and vacuum tightness is 0.001～0.07 MPa.
2. the method for claim 1, it is characterized in that polyamic acid is selected from gathers equal benzene tetramethyl amido acid, gathers the biphenyl tetracarboxylic amido acid and gathers a kind of in the benzophenone tetramethyl amido acid.
3. the method for claim 1, the mass percentage concentration that it is characterized in that polyamic acid solution is 1%～10%.
4. the method for claim 1, the particle diameter that it is characterized in that the silicon dioxide colloid ball is 0.1～1.5 micron.
5. the method for claim 1 is characterized in that PAA/SiO
2In the solution, PAA and SiO
2The mass ratio of colloidal spheres is 100: 30～100.
6. the method for claim 1 is characterized in that the hydrofluoric acid aqueous solution mass percentage concentration is 5-30%, and etching time is 2-20 hour.
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103467984A (en) * | 2013-09-18 | 2013-12-25 | 四川大学 | Porous polyimide nanometer composite film and preparation method thereof |
| CN103965503A (en) * | 2014-05-07 | 2014-08-06 | 哈尔滨工业大学 | Preparation method of polyimide film |
| WO2016027825A1 (en) * | 2014-08-20 | 2016-02-25 | 東京応化工業株式会社 | Varnish for porous polyimide film production and method for producing porous polyimide film using same |
| CN105449142A (en) * | 2015-12-30 | 2016-03-30 | 吉林省聚科高新材料有限公司 | Polyimide/nano-silica composite porous film containing carboxyl structure and preparation method thereof |
| WO2017038897A1 (en) * | 2015-09-04 | 2017-03-09 | 東京応化工業株式会社 | Method for manufacturing porous membrane |
| CN106552517A (en) * | 2015-09-30 | 2017-04-05 | 东京应化工业株式会社 | Barrier filter and filter method, photoetching medicinal liquid purify the manufacture method and Resist patterns forming method of product |
| CN106795314A (en) * | 2014-09-10 | 2017-05-31 | 东京应化工业株式会社 | The manufacture method of Porous polyimide film |
| CN109021282A (en) * | 2018-06-26 | 2018-12-18 | 中国工程物理研究院激光聚变研究中心 | The preparation method of monodisperse three dimensional ordered porous material and its material obtained |
| CN110499113A (en) * | 2019-08-09 | 2019-11-26 | 湖北锂诺新能源科技有限公司 | Lithium battery terminal adhesive tape and preparation method thereof |
| CN114395252A (en) * | 2021-12-30 | 2022-04-26 | 西北大学 | Preparation method of graphene/polyimide composite sponge with multilevel structure |
| CN115746380A (en) * | 2022-11-24 | 2023-03-07 | 慧迈材料科技(广东)有限公司 | Preparation method of polyimide porous composite film |
| EP4327919A1 (en) * | 2022-08-24 | 2024-02-28 | Tokyo Ohka Kogyo Co., Ltd. | Porous film |
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| CN100999589A (en) * | 2006-12-22 | 2007-07-18 | 东南大学 | Process for synthesizing composite film of polyacylimide/nano barium phthalate with high deelectric constant |
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| CN103467984B (en) * | 2013-09-18 | 2015-11-25 | 四川大学 | A kind of porous polyimide nano compound film and preparation method thereof |
| CN103467984A (en) * | 2013-09-18 | 2013-12-25 | 四川大学 | Porous polyimide nanometer composite film and preparation method thereof |
| CN103965503A (en) * | 2014-05-07 | 2014-08-06 | 哈尔滨工业大学 | Preparation method of polyimide film |
| WO2016027825A1 (en) * | 2014-08-20 | 2016-02-25 | 東京応化工業株式会社 | Varnish for porous polyimide film production and method for producing porous polyimide film using same |
| US10189968B2 (en) | 2014-08-20 | 2019-01-29 | Tokyo Ohka Kogyo Co., Ltd. | Varnish for porous polyimide film production and method for producing porous polyimide film using same |
| CN106795314A (en) * | 2014-09-10 | 2017-05-31 | 东京应化工业株式会社 | The manufacture method of Porous polyimide film |
| CN106795314B (en) * | 2014-09-10 | 2019-11-12 | 东京应化工业株式会社 | The manufacturing method of Porous polyimide film |
| WO2017038897A1 (en) * | 2015-09-04 | 2017-03-09 | 東京応化工業株式会社 | Method for manufacturing porous membrane |
| US10865286B2 (en) | 2015-09-04 | 2020-12-15 | Tokyo Ohka Kogyo Co., Ltd. | Method for manufacturing porous membrane |
| EP3159057A3 (en) * | 2015-09-30 | 2017-08-09 | Tokyo Ohka Kogyo Co., Ltd. | Filtration filter, filtration method, production method of purified liquid chemical product for lithography, and method of forming resist pattern |
| CN106552517A (en) * | 2015-09-30 | 2017-04-05 | 东京应化工业株式会社 | Barrier filter and filter method, photoetching medicinal liquid purify the manufacture method and Resist patterns forming method of product |
| US10429738B2 (en) | 2015-09-30 | 2019-10-01 | Tokyo Ohka Kogyo Co., Ltd. | Filtration filter, filtration method, production method of purified liquid chemical product for lithography, and method of forming resist pattern |
| CN106552517B (en) * | 2015-09-30 | 2021-10-26 | 东京应化工业株式会社 | Barrier filter, method for filtering, method for producing purified product of liquid chemical for lithography, and method for forming resist pattern |
| CN105449142A (en) * | 2015-12-30 | 2016-03-30 | 吉林省聚科高新材料有限公司 | Polyimide/nano-silica composite porous film containing carboxyl structure and preparation method thereof |
| CN109021282A (en) * | 2018-06-26 | 2018-12-18 | 中国工程物理研究院激光聚变研究中心 | The preparation method of monodisperse three dimensional ordered porous material and its material obtained |
| CN109021282B (en) * | 2018-06-26 | 2021-05-14 | 中国工程物理研究院激光聚变研究中心 | Preparation method of monodisperse three-dimensional ordered porous material and material prepared by same |
| CN110499113A (en) * | 2019-08-09 | 2019-11-26 | 湖北锂诺新能源科技有限公司 | Lithium battery terminal adhesive tape and preparation method thereof |
| CN114395252A (en) * | 2021-12-30 | 2022-04-26 | 西北大学 | Preparation method of graphene/polyimide composite sponge with multilevel structure |
| EP4327919A1 (en) * | 2022-08-24 | 2024-02-28 | Tokyo Ohka Kogyo Co., Ltd. | Porous film |
| CN115746380A (en) * | 2022-11-24 | 2023-03-07 | 慧迈材料科技(广东)有限公司 | Preparation method of polyimide porous composite film |
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Application publication date: 20120418 |