PERMEABILITY OF PEEK TO CARBON-DIOXIDE

Sorption and diffusion of carbon dioxide were measured in amorphous an d crystalline poly(aryl-ether-ether-ketone) or PEEK, at different temp eratures. The sorption follows Henry's law at all the investigated tem peratures, and the reduction of sorption in the crystalline sample cor responds to the reduction of the amorphous phase as derived from X-ray s. Due to a more tortuous path, the diffusion parameter in the crystal line sample is lower than in the amorphous one, whereas the activation energy of the diffusion process is similar for both the samples. The permeability to carbon dioxide was very low, comparable, or lower than other rigid polymers. (C) 1994 John Wiley & Sons, Inc.