TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The membrane further comprises: a second PFSA layer comprising the PFSA polymer; and a support layer contacting at least one of the perfluorocyclobutyl-containing layers, a first PFSA layer or second PFSA layer. The support layer is an expanded polytetrafluoroethylene support. The support is at least partially immersed in the perfluorocyclobutyl containing layer and/or the first PFSA layer, the first PFSA layer, or the second PFSA layer. The first perfluorocyclobutyl-containing layer further includes a fluoroelastomer. The perfluorocyclobutyl moieties have a structure of formula (a) or (b). The first layer comprises polymer has: a structure of formula ((E1(SO2X)d)-P1-Q1-P2) (I); a structure of formula (E2-P3-Q2-P4) (II); a structure of formula (E1(-R8-(SO3X)d)-P1-Q1-P2) (III); a structure of formula (E2-P3-Q2-P4) (IV); a structure of formula (E1(SO2X)d-P1-Q1-P2) (V); a structure of formula (E2-P3-Q2-P4) (VI), where (V) and (VI) are connected by a linking group L1 to form polymer units of formula (-(E2-P3-Q2-P4-)j-L1-(E1(SO2X)d-P1-Q1-P2-)i) (VII) and (-(E1(SO2X)d-P3-Q2-P4)i-L1-(E2-P1-Q1-P2-)j) (VIII); a structure of formula (E1(SO2X)d-P1-Q1-P2) (IX); and a structure of formula (E2(SO2X)f-P3) (X).E1(SO2X)d = a sulfonated aromatic containing moiety;E1a = an aromatic containing moiety;E2 = an unsulfonated aromatic-containing or aliphatic-containing moiety;X = -OH, halo, ester or -NH-S(=O)2-R4;d = number of (SO2X)d attached to E1;P1-P4 = absent, -O-, -S-, -SO-, -CO-, -SO2-, -NR1H-, NR2- or -R3;R2 = 1-25C alkyl, 1-25C aryl or 1-25C arylene;R3 = 1-25C alkylene, 1-25C perfluoroalkylene, perfluoro-alkylether, alkylether or 1-25C arylene;R4 = trifluoromethyl, 1-25C alkyl, 1-25C perfluoroalkylene, 1-25C aryl, or E1;Q1, Q2 = fluorinated cyclobutyl moiety;R8(SO2X)d = sulfonated aliphatic or aromatic containing moiety;L1 = linking group;i = 5;j = 6;E1, E2 = aromatic or aliphatic-containing moiety, where at least one of E1 and E2 include an aromatic group substituted with -SO2X;d = number of (SO2X) functional groups attached to E1;f = number of (SO2X) functional groups attached to E2; andQ1a = fluorinated cyclobutyl moiety.Provided that when d is greater than 0, f is 0 and when f is greater than 0, d is 0. Preferred Method: The method further comprises depositing the second PFSA-containing layer from the second PFSA solid in the liquid composition. A support layer is interposed between the first perfluorocyclobutyl-containing layer and the first PFSA-containing layer. The first perfluorocyclobutyl containing layer is dried before the first PFSA-containing layer is deposited.