ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The sorption behaviour of CO2 and N2 in poly(p-phenylene sulfide), PPS, crystallized in the presence of CO2 and N2O molecules was studied at 298 K in the pressure range of 1-30 bar. The CO2 transport properties of these samples were investigated at the same temperature in the pressure range of 1-20 bar. The temperature dependence of the CO2 transport parameters was examined between 293 and 343 K at a pressure of 5 bar, for the virgin material, thermal and CO2 crystallized specimen only. All measured properties are compared with those of PPS crystallized by annealing at vacuum conditions to a similar degree of crystallinity, and with the virgin, nearly amorphous material. For the samples crystallized in the presence of sorbed gases an increased CO2-solubility was observed. A part of unrelaxed free volume is proposed to remain in the samples after crystallization in presence of sorbed gas molecules. These voids formed under sorbed gas conditions seem to be stable even after removal of the sorbed molecules. The measured diffusion coefficients for CO2 were lower in the samples crystallized in the presence of gas molecules, compared to the virgin sample. This is expected to be due to an increased diffusive resistance by passing the interfaces of the formed voids. Permeability, which is governed by both, diffusion and sorption, undergoes non-uniform changes. An attempt is made to explain this behaviour based on the dual-mode-sorption and dual-mobility model.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1993.021940206
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