SDS Volume (4072)
Volume 70. Solubility of Gases in Glassy Polymers, p None
Original Measurements
Stern, S. A.; Vakil, U. M.; Mauze, G. R.; J. Polym. Sci. B: Polym. Phys. 27, 405-429 (1989).
Variables:
Room Temp:
259.4 - 315.4
$\pu{K}$
Pressure:
0 - 67
$\pu{kPa}$
Prepared by:
Method/Apparatus/Procedure:
The solubility was measured by a gravimetric method. The apparatus included a Cahn microbalance, Model 2000 RG.
Source and Purity of Materials:
- PBMA (Scientific Polymer Products of Ontario, NY) had $\rho^{26} = \pu{1.06 g mL-1}$, $T{\rm{g}}$ (DSC) = 295-308 K.
The minimum purity of ethane and n-butane (Linde Division of Union Carbide Corp.) were 99.0%.
Components:
- Ethane, $\ce{ C2H6 }$; [74-84-0] NIST WebBook
- Poly(n-butyl methacrylate) (PnBMA), $\ce{ (C8H14O2)n }$; [97-88-1] NIST WebBook
Experimental Data
Sorption isotherms of ethane are linear in the range 259-315 K. Solubility coefficients can be described by Van't Hoff equation
S = 5.25 × 10-5) - exp(-ΔHs/RT)cm3(STP)/cm3 cm Hg,
where ΔHs = -14.9 kJ/mol.
Sorption isotherms of butane are linear in the range 283-313 K: at lower temperatures they are convex to the pressure axis. The isotherms were represented by exponential relation
C = S(0)p - exp(σ · c),
where S(0) is the Henry's law solubility coefficient and σ is a constant which depends on temperature. The parameters of this equation are given below:
S(0) can be described by the Van't Hoff equation
S(0) = 5.24 × 10-4 exp(-ΔHg/RT)cm-3(STP)/cm-3 (cm Hg)-1, where ΔH1=-20.6 kJ/mol.
| $T$ ($\pu{K}$) | S ($\pu{cm3(STP) cm-3 cmHg-1}$) |
|---|---|
| 273 | 0.432 |
| 283 | 0.336 |
| 293 | 0.252 |
| 303 | 0.176 |
| 313 | 0.179 |
