T. Kajitani et al., GAS-PERMEABILITY IN THE POLYSTYRENE FILMS UNIAXIALLY DRAWN UNDER CO2 PLASTICIZING, MATERIALS RESEARCH INNOVATIONS, 1(1), 1997, pp. 53-56
Gas permeability coefficients, Ps, of CO2, O-2, and N-2 have been meas
ured in four kinds of polystyrene (PS) films: an unconditioned film wi
th no orientation (1), a high pressure CO2-conditioned film with no or
ientation (2), an uniaxially hot-drawn film with some orientation (3),
and a film uniaxially drawn under CO2 plasticizing with some orientat
ion (4). Wide angle X-ray diffraction (WAXD) scans for each sample hav
e also been made. High-pressure CO2-conditioning effect was confirmed
from the result that P values for any permeation gas in sample 2 were
larger than those in sample 1. Values of P for any gas in sample 3 wer
e almost close to those in sample 1 and decreased slightly with Herman
s orientation function, f. Gas permeability coefficients in sample 4 a
re larger than those in sample 3 over the whole range of f studied in
this work and increased with f. These results were discussed from a vi
ewpoint of inter-segmental distances for PS films.