A type of anhydrous proton-conducting membranes are prepared via in situ cross-linking of polymerizable oils containing polyamidoamine (PAMAM) dendrimer-based macromolecular protic ionic liquids (PILs). The resultant composite membranes are transparent, flexible, and thermally stable up to 350 degrees C. Under anhydrous conditions, the macromolecular PIL-based membranes show proton conductivity of 1.2 x 10(-2) S cm(-1) at 160 degrees C, which is higher than that of the membranes containing small-molecule PILs. Furthermore, the macromolecular PIL-based composite membranes have much better PIL retention ability than which containing small-molecule PILs. These properties make this type of macromolecular PIL-based membranes suitable for high-temperature anhydrous polymer electrolyte membrane fuel cells. (C) 2011 Elsevier B.V. All rights reserved.