To　develop　high　performance　anion　exchange　membranes　(AEMs),　a　novel　bisphenol　monomer　bearing　eight　benzylmethyl　groups　at　the　outer　edge　of　the　molecule　was　synthesized,　which　after　condensation　polymerization　with　various　amounts　of　4,4′-dihydroxydiphenylsulfone　and　4,4′-difluorobenzophenone　yielded　novel　poly(arylene　ether)s　with　densely　located　benzylmethyl　groups.　These　benzylmethyl　groups　were　then　converted　to　quaternary　ammonium　groups　by　radical-initiated　bromination　and　quaternization　in　tandem,　leading　to　the　emergence　of　densely　quaternized　poly(arylene　ether　sulfone)s　(QA-PAEs)　with　controlled　ion　exchange　capacities　(IECs)　ranging　from　1.61　to　2.32　mmol　g−1.　Both　small-angle　X-ray　scattering　(SAXS)　and　transmission　electron　microscopy　(TEM)　studies　revealed　distinct　phase　separation　in　the　QA-PAEs.　The　QA-PAE-40　with　an　IEC　of　2.32　mmol　g−1　exhibited　a　Br−　conductivity　of　9.2　mS　cm−1　and　a　SO4　2−　conductivity　of　14.0　mS　cm−1　at　room　temperature,　much　higher　than　those　of　a　control　membrane　with　a　similar　IEC　but　without　obvious　phase　separation.　Therefore,　phase　separation　of　AEMs　was　validated　to　be　advantageous　for　the　efficient　conducting　of　anions.　The　experimental　results　also　showed　that　the　QA-PAEs　were　promising　AEM　materials,　especially　for　non-alkaline　applications.　©　2018　Elsevier　B.V.