CN115490855A - Polyimide precursor and polyimide film - Google Patents
Polyimide precursor and polyimide film Download PDFInfo
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- CN115490855A CN115490855A CN202211134531.0A CN202211134531A CN115490855A CN 115490855 A CN115490855 A CN 115490855A CN 202211134531 A CN202211134531 A CN 202211134531A CN 115490855 A CN115490855 A CN 115490855A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1067—Wholly aromatic polyimides, i.e. having both tetracarboxylic and diamino moieties aromatically bound
- C08G73/1071—Wholly aromatic polyimides containing oxygen in the form of ether bonds in the main chain
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1003—Preparatory processes
- C08G73/1007—Preparatory processes from tetracarboxylic acids or derivatives and diamines
- C08G73/1028—Preparatory processes from tetracarboxylic acids or derivatives and diamines characterised by the process itself, e.g. steps, continuous
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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
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
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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
- 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
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- Chemical Kinetics & Catalysis (AREA)
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- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
The invention provides a polyimide precursor and a polyimide film, wherein the polyimide precursor is imidized polyamic acid obtained by ring-closing and dehydrating partial amido bonds in wholly aromatic polyamic acid. According to the invention, the imidized polyamic acid is obtained by ring-closing and dehydrating part of amide bonds in the wholly aromatic polyamic acid, and when the imidized polyamic acid is used as a polyimide precursor to obtain a polyimide film, the obtained polyimide film can be ensured to have higher imidization degree, so that the polyimide film with better performance is obtained.
Description
Technical Field
The invention relates to the technical field of polyimide, in particular to a polyimide precursor and a polyimide film.
Background
Polyimide (PI) is a polymer material having the highest levels of heat resistance, chemical resistance, electrical insulation, chemical resistance, and weather resistance among organic materials, based on a rigid aromatic main chain and an imide ring having very excellent chemical stability.
Although the wholly aromatic polyimide has excellent thermal and mechanical properties, most wholly aromatic polyimides have poor solubility in organic solvents and even cannot be solution cast into films. Currently, most of wholly aromatic polyimides are dissolved in an organic solvent in the form of polyamic acid (poly (amic acid)), and are not dissolved when formed into polyimides, and therefore the processing of polyimides is generally performed as follows: using a solution of polyamic acid, a desired film or a molded article, a coated film is obtained by drying the solution, and then imidized by heating.
However, the properties of the polyimide film are not only related to the structure of the polyimide molecule itself, but also largely affected by the imidization degree. However, it is difficult to obtain a film having excellent performance because the polyamic acid is dissolved in an organic solvent in the form of polyamic acid and dried from a solution of polyamic acid to obtain a desired film, molded product, or coating film, and the imidization degree is low.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a polyimide precursor and a polyimide film, wherein imidized polyamic acid is obtained by performing closed-loop dehydration on part of amide bonds in wholly aromatic polyamic acid, and when the polyimide film is obtained by using the imidized polyamic acid as the polyimide precursor, the polyimide film with higher imidization degree can be ensured, so that the polyimide film with better performance is obtained.
The polyimide precursor is imidized polyamic acid obtained by ring-closing and dehydrating partial amide bonds in wholly aromatic polyamic acid.
Preferably, the wholly aromatic polyamic acid is a polyamic acid obtained by polycondensation of an aromatic dianhydride and an aromatic diamine.
Preferably, the aromatic dianhydride is at least one of pyromellitic dianhydride PMDA, biphenyl tetracarboxylic dianhydride BPDA, or benzophenone tetracarboxylic dianhydride BTDA; the aromatic diamine is at least one of diaminodiphenyl ether ODA or p-phenylenediamine PDA.
Preferably, the aromatic dianhydride is pyromellitic dianhydride PMDA and the aromatic diamine is oxydianiline ODA alone or a mixed diamine of oxydianiline ODA and paraphenylenediamine PDA.
Preferably, the imidized polyamic acid has a imidization degree of 0.1 to 0.3.
In the present invention, the infrared spectrum of the polyamic acid was measured to calculate 1375cm -1 Absorbance of imide C-N at 1500cm -1 The ratio of absorbance of C-H substituted at the para position gives the imidization degree.
Preferably, the ring-closing dehydration is carried out in an organic solvent capable of dissolving the imidized polyamide acid.
Preferably, the organic solvent is a phenolic solvent, preferably at least one of p-chlorophenol, m-cresol or o-cresol.
In the present invention, when conventional N-methyl-2-pyrrolidone NMP, dimethylformamide DMF, dimethylacetamide DMAc or dimethylsulfoxide DMSO is used as a solvent, some amide bonds in wholly aromatic polyamic acid are separated out once they are subjected to ring closure dehydration, and the resulting imidized polyamic acid cannot be formed into a film.
Preferably, the ring-closing dehydration is achieved by heating the wholly aromatic polyamic acid to more than 150 ℃ for not more than 1h.
The invention provides a polyimide film, which is obtained by coating a film on a supporting substrate by using a solution of a polyimide precursor and heating for imidization.
Preferably, the thermal imidization comprises: drying at 60-80 deg.C for 1-2h, heating to 160-180 deg.C, drying for 1-2h, and heating to 360-390 deg.C for 0.5-1h.
The polyimide film of the present invention has improved strength and elongation, excellent mechanical properties, and lower CTE and yellowness (YI value).
Detailed Description
Hereinafter, the technical solution of the present invention will be described in detail by specific examples, but these examples should be explicitly proposed for illustration, but should not be construed as limiting the scope of the present invention.
Example 1
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, adding 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA) and 2.0024g (10 mmol) of 4,4' -diaminodiphenyl ether (ODA) into 40g of parachlorophenol, stirring and reacting for 5 hours at 40 ℃, then heating to 160 ℃, preserving heat and stirring and reacting for 0.5 hour to obtain an imidized polyamic acid solution, namely a polyimide precursor solution;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying for 2h in a drying oven at 70 ℃ under a reduced pressure condition, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuously heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Example 2
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, adding 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA) and 2.0024g (10 mmol) of 4,4' -diaminodiphenyl ether (ODA) into 40g of m-cresol, stirring and reacting at 30 ℃ for 5h, then heating to 160 ℃, preserving heat and stirring and reacting for 0.5h to obtain an imidized polyamic acid solution, namely a polyimide precursor solution;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying for 2h in a drying oven at 70 ℃ under a reduced pressure condition, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuously heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Example 3
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, adding 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA) and 2.0024g (10 mmol) of 4,4' -diaminodiphenyl ether (ODA) into 40g of o-cresol, stirring and reacting at 50 ℃ for 5h, then heating to 160 ℃, preserving heat and stirring and reacting for 0.5h to obtain an imidized polyamic acid solution, namely a polyimide precursor solution;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying for 2h in a drying oven at 70 ℃ under a reduced pressure condition, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuously heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Example 4
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA), 1.2014g (6 mmol) of 4,4' -diaminodiphenyl ether (ODA) and 0.4326g (4 mmol) of p-Phenylenediamine (PDA) are added into 40g of p-chlorophenol, stirred and reacted for 5 hours at 40 ℃, then heated to 160 ℃, kept warm and stirred and reacted for 0.5 hour, and imidized polyamic acid solution, namely polyimide precursor solution is obtained;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying the glass substrate in a drying oven at 70 ℃ for 2 hours under reduced pressure, then placing the glass substrate in a tube furnace, heating to 170 ℃ for drying for 1 hour, continuously heating to 380 ℃ for drying for 0.5 hour, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Example 5
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, adding 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA), 1.2014g (6 mmol) of 4,4' -diaminodiphenyl ether (ODA) and 0.4326g (4 mmol) of p-Phenylenediamine (PDA) into 40g of m-cresol, stirring and reacting at 30 ℃ for 5h, then heating to 160 ℃, keeping the temperature and stirring and reacting for 0.5h to obtain an imidized polyamic acid solution, namely a polyimide precursor solution;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying for 2h in a drying oven at 70 ℃ under a reduced pressure condition, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuously heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Example 6
A polyimide precursor and a polyimide film are prepared by the following steps:
under the protection of nitrogen, adding 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA), 1.2014g (6 mmol) of 4,4' -diaminodiphenyl ether (ODA) and 0.4326g (4 mmol) of p-Phenylenediamine (PDA) into 40g of o-cresol, stirring and reacting at 50 ℃ for 5h, then heating to 160 ℃, keeping the temperature and stirring and reacting for 0.5h to obtain an imidized polyamic acid solution, namely a polyimide precursor solution;
and (2) coating the solution of the polyimide precursor on a glass substrate, drying for 2h in a drying oven at 70 ℃ under a reduced pressure condition, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuously heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Comparative example 1
A preparation method of the polyamic acid and the polyimide film comprises the following steps:
under the protection of nitrogen, 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA) and 2.0024g (10 mmol) of 4,4' -diaminodiphenyl ether (ODA) are added into 40g of N, N-dimethylacetamide (DMAc) and stirred for reaction for 5 hours at 40 ℃, and then a polyamic acid solution is obtained;
and (3) coating the polyamic acid solution on a glass substrate, drying in a drying oven at 70 ℃ for 2h under reduced pressure, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuing heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
Comparative example 2
A preparation method of the polyamic acid and the polyimide film comprises the following steps:
under the protection of nitrogen, 2.1812g (10 mmol) of pyromellitic dianhydride (PMDA), 1.2014g (6 mmol) of 4,4' -diaminodiphenyl ether (ODA) and 0.4326g (4 mmol) of p-Phenylenediamine (PDA) are added into 40g of N, N-dimethylacetamide (DMAc) and stirred for reaction for 5 hours at 40 ℃ to obtain a polyamic acid solution;
and (3) coating the polyamic acid solution on a glass substrate, drying in a drying oven at 70 ℃ for 2h under reduced pressure, then placing in a tube furnace, heating to 170 ℃ for drying for 1h, continuing heating to 380 ℃ for drying for 0.5h, cooling to room temperature, taking out the glass substrate, and stripping to obtain the polyimide film with the thickness of 20 microns.
The polyimide films obtained in examples 1 to 6 and comparative examples 1 to 2 were subjected to a performance test:
coefficient of linear thermal expansion CTE: measuring at a temperature range of 50-300 deg.C at a heating rate of 10 deg.C/min by applying a 50mN load under nitrogen atmosphere with a thermomechanical analyzer to obtain an average value;
the mechanical properties are measured by a universal material testing machine according to GB/T1040.3-2006;
yellowness index YI: the yellowness index was determined according to the ASTM E313 standard using a uv-vis spectrophotometer.
TABLE 1 test results of polyimide films obtained in examples and comparative examples
As can be seen from the results of table 1, the polyimide films of examples not only have improved strength and elongation and excellent mechanical properties, but also have lower CTE and yellowness (YI value) than those of the polyimide films of comparative examples.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (10)
1. A polyimide precursor is an imidized polyamic acid obtained by ring-closing and dehydrating a part of amide bonds in a wholly aromatic polyamic acid.
2. The polyimide precursor according to claim 1, wherein the wholly aromatic polyamic acid is a polyamic acid obtained by polycondensation of an aromatic dianhydride and an aromatic diamine.
3. The polyimide precursor according to claim 2, wherein the aromatic dianhydride is at least one of pyromellitic dianhydride PMDA, biphenyl tetracarboxylic dianhydride BPDA, or benzophenone tetracarboxylic dianhydride BTDA; the aromatic diamine is at least one of diaminodiphenyl ether ODA or p-phenylenediamine PDA.
4. The polyimide precursor according to claim 3, wherein the aromatic dianhydride is pyromellitic dianhydride PMDA and the aromatic diamine is oxydianiline ODA alone or a mixed diamine of oxydianiline ODA and paraphenylenediamine PDA.
5. The polyimide precursor according to any one of claims 1 to 4, wherein the imidized polyamic acid has a imidization degree of 0.1 to 0.3.
6. The polyimide precursor according to any one of claims 1 to 5, wherein the ring-closing dehydration is carried out in an organic solvent capable of dissolving the imidized polyamide acid.
7. The polyimide precursor according to claim 6, wherein the organic solvent is a phenolic solvent, preferably at least one of p-chlorophenol, m-cresol, or o-cresol.
8. The polyimide precursor according to any one of claims 1 to 7, wherein the ring-closing dehydration is performed by heating the wholly aromatic polyamic acid to more than 150 ℃ for not more than 1 hour.
9. A polyimide film obtained by coating a solution of the polyimide precursor according to any one of claims 1 to 8 on a supporting substrate and heating for imidization.
10. The polyimide film according to claim 9, wherein the thermal imidization comprises: drying at 60-80 deg.C for 1-2h, heating to 160-180 deg.C, drying for 1-2h, and heating to 360-390 deg.C for 0.5-1h.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211134531.0A CN115490855A (en) | 2022-09-19 | 2022-09-19 | Polyimide precursor and polyimide film |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1160600A (en) * | 1966-11-08 | 1969-08-06 | Rhone Poulenc Sa | New Polyimides and Their Production |
| JPH06192419A (en) * | 1992-12-25 | 1994-07-12 | Shin Etsu Chem Co Ltd | Production of polyimide film |
| JPH1149857A (en) * | 1986-11-29 | 1999-02-23 | Kanegafuchi Chem Ind Co Ltd | Production of polyimide excellent in thermal dimensional stability |
| JP2003292643A (en) * | 2002-04-03 | 2003-10-15 | Teijin Ltd | Polyimide precursor film and method for producing polyimide film |
| JP2007162005A (en) * | 2005-11-16 | 2007-06-28 | Du Pont Toray Co Ltd | Polyimide film and its manufacturing method |
| US20150045481A1 (en) * | 2012-03-09 | 2015-02-12 | Korea Advanced Institute Of Science And Technology | Asymmetric Diamine Compounds Containing Two Functional Groups and Polymers Therefrom |
| CN105801856A (en) * | 2016-03-25 | 2016-07-27 | 中国科学院重庆绿色智能技术研究院 | Colorless transparent high-performance low-surface-roughness polyimide optical thin film material and preparation method thereof |
| JP2019104909A (en) * | 2017-12-08 | 2019-06-27 | ドゥーサン コーポレイション | Polyamic acid solution, transparent polyimide resin and transparent substrate using the same |
| CN114213657A (en) * | 2022-01-17 | 2022-03-22 | 湖南工业大学 | Intrinsic black polyimide and preparation method and application thereof |
| CN115505123A (en) * | 2021-06-22 | 2022-12-23 | 北京化工大学 | Polyimide film and method for producing polyimide film |
-
2022
- 2022-09-19 CN CN202211134531.0A patent/CN115490855A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1160600A (en) * | 1966-11-08 | 1969-08-06 | Rhone Poulenc Sa | New Polyimides and Their Production |
| JPH1149857A (en) * | 1986-11-29 | 1999-02-23 | Kanegafuchi Chem Ind Co Ltd | Production of polyimide excellent in thermal dimensional stability |
| JPH06192419A (en) * | 1992-12-25 | 1994-07-12 | Shin Etsu Chem Co Ltd | Production of polyimide film |
| JP2003292643A (en) * | 2002-04-03 | 2003-10-15 | Teijin Ltd | Polyimide precursor film and method for producing polyimide film |
| JP2007162005A (en) * | 2005-11-16 | 2007-06-28 | Du Pont Toray Co Ltd | Polyimide film and its manufacturing method |
| US20150045481A1 (en) * | 2012-03-09 | 2015-02-12 | Korea Advanced Institute Of Science And Technology | Asymmetric Diamine Compounds Containing Two Functional Groups and Polymers Therefrom |
| CN105801856A (en) * | 2016-03-25 | 2016-07-27 | 中国科学院重庆绿色智能技术研究院 | Colorless transparent high-performance low-surface-roughness polyimide optical thin film material and preparation method thereof |
| JP2019104909A (en) * | 2017-12-08 | 2019-06-27 | ドゥーサン コーポレイション | Polyamic acid solution, transparent polyimide resin and transparent substrate using the same |
| CN115505123A (en) * | 2021-06-22 | 2022-12-23 | 北京化工大学 | Polyimide film and method for producing polyimide film |
| CN114213657A (en) * | 2022-01-17 | 2022-03-22 | 湖南工业大学 | Intrinsic black polyimide and preparation method and application thereof |
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