Due to its wide range of excellent properties, colorless and transparent polyimide can basically meet the needs of space telescope sunshields and antenna reflection collector materials.
" Preparation of alumina-based nanomaterials and research on superhydrophobic surfaces " In the article, high light transmittance, super flexibility, super foldability and processability were prepared by mixing ionic liquid (Ll) into CPI and using an experimental coating machine. CPI composite film.
Preparation of colorless transparent polyimide film
1. Preparation of CPI membrane
Weigh (2.72 mmol, 0.8724 g) TFMB diamine reaction monomer in a 100 mL three-necked flask, add 20 mL of anhydrous DMAc, stir at 0°C for 20 min to fully dissolve; then add (2.72 mmol, 1.2103 g) hexafluorodianhydride (6FDA), then react at 0°C for 2h and at room temperature for 14h to obtain transparent polyamic acid (PAA). Then pour the solution on one side of a clean and smooth glass substrate, scrape it flat with a scraper and control its thickness, and place it on a horizontal substrate in a Drying Oven for programmed temperature rise at 80°C/2h, 110 ° C /2h, 150°c / 2h, 170°c / 2h, 190°c/2h, 210°c / 1h, finally get the CPI film.
In addition, this paper also used the above method to prepare yellow polyimide film PI (Kapton) (ODA/PMDA) and fragile polyimide film PI1 (DABA/6FDA), PI2 (ODA/CPDA) as a comparison Experiments and Reference Experiments.
2. Preparation of CPI composite membrane
Figure 3-1 is a schematic diagram of the preparation method and synthesis route of the CPI composite membrane. As can be seen from the figure, the first half is to prepare colorless and transparent polyamic acid (PAA), which is the same as the above method. In the second half, different contents (1wt%, 3wt%, 5wt%, 8wt% and 10wt%) of ionic liquid l(ILl) were mixed with colorless and transparent PAA solution, and mechanically stirred at 25°C for 8h , it was found that the mixed solution became more transparent. Then pour the solution on one side of a clean and smooth glass substrate, scrape it flat with a scraper and control its thickness, and place it on a horizontal substrate in a Drying Oven for programmed temperature rise at 80°C/2h, 110°c/ 2h, 150°C/2h, 170°C/2h, 190°C/2h, 210°C/1h, and finally obtain a colorless and transparent polyimide composite film IL1/CPI, and the specific feeding amount is shown in Table 3-3 Show.
Use the same method to prepare colorless and transparent PAA, and then mix different contents (3wt%, 5wt%) of different types of ionic liquids 2, 3, 4 (IL2, IL3, IL4) with colorless and transparent polyamic acid (PAA) Mixed, stirred mechanically at 25°C for 8h, found that the mixed solution became more transparent, then poured the solution on one side of a clean and smooth glass substrate, scraped it with a scraper and controlled its thickness, under the same conditions Under thermal imidization reaction, IL2/CPI, IL3/CPI, IL4/CPI were obtained.
