| 摘要 |
An improved gas separation membrane comprises a thin discriminating layer consisting predominantly of a carbonate polymer derived from a bisphenol corresponding to formula I <CHEM> wherein R at each occurrence is independently H, Cl, Br, or C1-C4 alkyl and R<1> is -CO-, -S-, -SO2-, -O-, a C1-C6 divalent hydrocarbon radical, or a C1-C6 divalent fluorocarbon radical, or inertly substituted C1-C6 divalent hydrocarbon radical, with the proviso that at least 25 weight percent of the moieties derived from the bisphenol of formula I present in the discriminating layer bear R groups which are exclusively Br or Cl, said gas separation membrane exhibiting a separation factor for oxygen and nitrogen at the ambient temperature of at least 6.1. The membrane has particular application to separating oxygen from nitrogen, or a nitrogen-containing gas. |
