The response of amorphous model PEO48NaI, PEO20NaI and PEO3NaI polymer electrolytes to a rapid increase in temperature followed by a cooling phase of similar duration is investigated by molecular dynamics (MD) simulations. Analyses of the thermodynamic properties, polymer structure and ionic association show that the polymer and, the salt phase separate upon heating. In agreement with experimental findings on the so-called ＇salting-out＇ effect, these final states are not reversible on the time-scale of the MD simulations.