A combination membrane having both gas barrier properties and selective oxygen-absorbing and -carrying capability was prepared by complexing poly(vinylidene dichloride-co-vinylimidazole) and meso-tetrakis-(α,α,α,α-o-pivalamidophenyl) porphyrinatocobalt (CoP). The vinylidene dichloride copolymer was selected because of its low physical gas permeability and its dense and tough thin-membrane formability even after the CoP complexation. Oxygen permeation was selectively facilitated with the CoP carrier fixed in the membrane, and high oxygen permselectivity (facilitation factor > 25, oxygen/nitrogen permselectivity > 100, permeability 10-10 cm3 (STP) cm cm-2 s-1 cmHg-1) was observed, e.g., for the membrane containing > 20 wt % CoP at an upstream oxygen partial pressure of 0.5 cmHg. The facilitated oxygen transport was properly analyzed by a dual-mode model to give permeation parameters of the membrane such as the postulated diffusion coefficient of oxygen hopping via the fixed CoP carrier (DC). DC was inversely proportional to the average distance between the CoP carrier sites.
|Number of pages||5|
|Journal||Journal of Physical Chemistry B|
|Publication status||Published - 1998 Oct 29|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry