Components:
(1) Carbon dioxide,
CO2; [124-38-9]
NIST WebBook
(2) Copoly(pyromellitic dianhydride-oxydianiline),
(C22H10N2O5)n; [25036-53-7]
NIST WebBook
Original Measurements
Hachisuka, H.; Tsujita, Y.; Takizawa, A.; Kinoshita, T.; Polym. J. 21, 681 (1989).
Variables:
Ambient temperature: 298 K
Pressure: 0 - 1.200 kPa
Prepared by:
Method/Apparatus/Procedure:
Sorption measurement was carried out by Cahn 2000 electromicro-balance.
Source and Purity of Materials:
- CO2: purity 99.9%. Polyimide: prepared by imidization of the polyamide produced by the reaction of pyromellitic acid dianhydride with 4,4' diaminodiphenyl ether in N-methylpyrrolidone solution. Imidization was carried out at 423 K for 50-400 h in vacuo. An additional sample with 100% imide content was also studied. For the thermally treated samples, the imide content lay in the range 35% to 58%.
Tg of unimidized polymer and polyimide were equal to 428 and 683 K, respectively.
Estimated Errors:
Ambient temperature: No information given.
Experimental Values:
Table 1. Dual mode sorption parameters as a function of imide content (%) of CO2 in polyimide films (The original data were represented graphically)
| H (cm3(STP)/cm3 cmHg-1) | C'H (cm3/cm3) | b (cm Hg) |
|---|---|---|
| 5.96 x 10-2 | 2.14 | 4.7 x 10-3 |
| 8.10 x 10-2 | 72.84 | 6.1 x 10-3 |
| 8.72 x 10-2 | 273.54 | 7.2 x 10-3 |
| 9.56 x 10-2 | 211.76 | 7.3 x 10-3 |
| 9.22 x 10-2 | 175.26 | 7.5 x 10-3 |
| 7.20 x 10-2 | 34.44 | 8.4 x 10-3 |
Table 2. Sorption isotherms of CO2 in the films imidized for various periods at 423 K (The original data were represented graphically)
| P1 (kPa) | Sorption (V1/V2) |
|---|---|
| 49.0 | 3.08 |
| 97.0 | 5.32 |
| 199.0 | 9.37 |
| 301.0 | 12.67 |
| 400.0 | 15.97 |
| 501.0 | 18.67 |
| 596.0 | 20.97 |
| 696.0 | 23.17 |
| 800.0 | 25.54 |
| 900.0 | 27.33 |
| 68.0 | 6.47 |
| 135.0 | 9.91 |
| 268.0 | 14.91 |
| 398.0 | 18.2 |
| 534.0 | 21.43 |
| 665.0 | 24.03 |
| 799.0 | 26.5 |
| 906.0 | 28.36 |
| 1052.0 | 30.45 |
| 1191.0 | 32.6 |
| 134.0 | 12.62 |
| 295.0 | 19.18 |
| 399.0 | 22.55 |
| 533.0 | 25.97 |
| 665.0 | 29.01 |
| 782.0 | 31.74 |
| 910.0 | 34.09 |
| 1056.0 | 36.68 |
| 1174.0 | 38.47 |
| 64.0 | 9.94 |
| 135.0 | 13.88 |
| 264.0 | 19.82 |
| 400.0 | 23.87 |
| 553.0 | 27.85 |
| 667.0 | 30.46 |
| 800.0 | 33.25 |
| 924.0 | 35.41 |
| 1044.0 | 37.44 |
| 1178.0 | 39.54 |
| 132.0 | 14.89 |
| 266.0 | 20.83 |
| 395.0 | 24.94 |
| 519.0 | 28.62 |
| 660.0 | 31.72 |
| 791.0 | 34.89 |
| 936.0 | 37.48 |
| 1048.0 | 39.46 |
