Development of thin-film composite hollow-fiber membranes from modified polyphenylene oxide for gas separation applications

The effect of sulfonation and bromination-sulfonation on the gas transport properties of polyphenylene oxide has been investigated. These high-performance modified polymers have been studied in the form of TFC membranes by solution coating on the skin side of polyetherimide hollow fibers. TFC membrane modules prepared from sulfonated-brominated polyphenylene oxide as the active layer coated on polyetherimide hollow fibers. Stability of the TFC membranes was greatly improved when a wet feed stream was used instead of a dry one. Water vapor in the feed stream most likely prevented the active layer from stress cracking on drying. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 275–282, 2001