Comment by Composite Analytica on 07 Jul 2010 at 16:59:50
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|responses: 0|
Dear Sandra,
Below some diffusion, solubility, permeability coefficients in some membranes at ambient conditions (25 degrees Celsius ant atmospheiric pressure), no moisture present:
Table Source: M. Wojcik, Nuclear Instruments and Methods in Physics Research B61 (1991) 8-11 North-Holland
| Material |
Diffusivity [1E-10 cm2/s] |
Solubility[-] |
Permeability[1E-8 cm2/s] |
| General Rubber |
1000 |
12 |
120 |
| Butyl Rubber |
49 |
4.4 |
2.1 |
| Polyurethane Soft |
408 |
5.6 |
23 |
| Polyurethane Hard |
88 |
7.9 |
4.9 |
| Polyvinylchloride soft |
420 |
10 |
42 |
| Polyvinylchloride hard |
140 |
5.2 |
7.3 |
| Polyamide Supronyl |
6.1 |
3.4 |
0.2 |
| Plexi Glas (PMMA) |
6.2 |
8.2 |
0.5 |
The Radon diffusion through Epoxy resin is very dependent on the type of Epoxy (Bisphenol A, Bisphenol F, Novolac Epoxy) and curing agents used (Aliphatic Amine, Cycloalipatic amine, Aromatic Amine, Anhydride, Dcy, Polysulfide, Polyamides). So the Radon peremation behaviour depends on the specific application.
Permeation of Radon, Xenon and Krypton in Vinyl Ester, Polyester, Epoxy and evenutally Polyurethane material can be assessed using
CheFEM. Asssessments include Chemical and Physical ageing of the cast polymers and filled (reinforced) polymers.
Kind Regards,
Composite Analytica
