Synthesis of galvinoxyl unit-containing derivatives of poly(phenylacetylene) and polystyrene, and oxygen permeation behavior of their membranes

Poly(phenylacetylene) and polystyrene which contain galvinoxyl and trimethy lsilyl units were synthesized by copolymerization of the corresponding mono mers or polymer reaction of the corresponding methyl benzoate polymers with [3,5-di-tert-butyl-4-(trimethylsiloxy)-phenyl]lithium. The copolymers obta ined from (4-trimethylsilyl)phenylacetylene and (4-ethynylphenyl)hydrogalvi noxyl using [Rh(norbornadiene)Cl](2) catalyst had very high molecular weigh ts. On the contrary, the copolymers of (4-trimethylsilyl)styrene and methyl 4-vinylbenzoate nearly completely reacted with [3,5-di-tert-butyl-4-(trime thylsiloxy)phenyl]lithium to give the corresponding galvinoxyl-copolymers w ith high molecular weights. The hydrogalvinoxyl could be fabricated to self -supporting membranes. We succeeded in obtaining such stable polyradical me mbranes that the initial spin concentration was maintained for a few days. The oxygen permselectivity (alpha = P-O2/P-N2) increased and the oxygen per meability (P-O2) decreased as galvinoxyl units increased, owing to the rigi d character of galvinoxyl moiety. (C) 2000 Elsevier Science Ltd. All rights reserved.