ISSN:
0887-624X
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The permeability (SD) of ozone in a silicone polycarbonate copolymer has been measured by monitoring the depletion of 10,10′-dimethyl-9,9′-biacridylidene (DBA) impregnated into the polymer. The quantity (2SD)1/2 varies linearly with membrane thickness. Extrapolation of this linear relationship to zero thickness provides a positive y-intercept that can be taken to be the intrinsic permeability of ozone in the silicone portion of this copolymer [SD = 115 ± 17 × 10-9 (cm3 gas) cm sec-1 cm-2 (cmHg, ΔP)-1]. This result compared favorably with the modeled permeability of ozone in silicone homopolymers [142 ± 15 × 10-9 (cm3 gas) cm sec-1 cm-2 (cmHg, ΔP)-1]. The lower permeability determined for the copolymer, when compared with the modeled value, was attributed to a reduced mobility of the amorphous silicone blocks caused by the presence of the crystalline polycarbonte blocks. The permeability was shown to be independent of ozone concentrations, flow rate, temperature, and humidity over the ranges used in these experiments. This method identifies a technique that may be useful in quantitating the permeability of ozone in packaging materials, tire sidewalls, and industrial polymers.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pola.1987.080250817
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