A NOTE ON THE EFFECTS OF MONO-BROMINATION AND DI-BROMINATION ON THE TRANSPORT-PROPERTIES OF POLY(2,6-DIMETHYLPHENYLENE OXIDE)

The permeability of poly (2,6-dimethylphenylene oxide) (PPO) to carbon dioxide and methane at 35°C can be increased more than 100% by aryl-bromination, depending on the extent of bromination, whereas, the carbon dioxide/methane permselectivity of the polymer, which ranges from 17-20, is changed only slightly by bromination. The increase in permeability results primarily from a marked increase in the penetrant diffusivity, although the penetrant solubility is also moderately increased by bromination. These results are interpreted in terms of changes in packing density and chain torsional mobility brought about by aryl-bromination of the polymer. © 1990.