he permeability of two polypyrrolone membranes to H2

O2

and N2has been determined over a temperature range of 30-90℃. The introduction of bulky group

-C(CF3)2-

into the backbone of this polymer appears to result in a significant increase in gas permeability coefficient. The permeability changes in this case was primarily due to the alteration of diffusivity factors. This result contributes to the inhibition of chain packing and segmental mobility. The permeability coefficient increased with the rise of temperature

while the selective separation factor decreased correspondingly. Within the temperature range

the effects of tem-perature on gas permeability coefficients can be described well by the Arrhenius form. The apparent activation energy for permeation

Ep

increases as the penet-rant size increases

which follows the expected general trends.