HIGHLY OXYGEN PERMSELECTIVE MEMBRANE OF COBALT-COMPLEXED POLYAZOMETHINE CONTAINING TRIDENTATE LIGAND AND OLIGOSILOXANE IN THE REPEATING PAIRS OF THE MAIN-CHAIN

Four new polyazomethines containing a tridentate ligand and different length of oligosiloxane in the repeating pairs were synthesized and co balt(II) salt was added to the polymer to yield a cobalt(II)-complexed membrane. Oxygen permselectivities of the cobalt(II)-complexed membra nes at one atm pressure difference were excellent: oxygen permeability coefficient (P-O2) = 1.1 - 2.9 x 10(-8)cm(3)(STP). cm . cm(-2). s(-1) . cmHg(-1), oxygen separation factor (alpha = P-O2/P-N2) = 3.4 - 4.0, which were very close to those on the upper boundary line reported in the literature [L. M. Robeson, J. Membrane Sci., 62, 165 (1991)]. Sinc e P-O2 increased with decrease in the upstream pressure and P-N2 was i ndependent, a cobalt(II)-complex in the membrane is shown to function as a fixed oxygen carrier.