Towards understanding hydrophobic recovery of plasma treated polymers: Storing in high polarity liquids suppresses hydrophobic recovery

► Hydrophobic recovery of air plasma treated polyethylene films was studied. ► Plasma treated polymer films were immersed into liquids with various polarities. ► Immersion into high polarity liquids slowed markedly the hydrophobic recovery. ► Hydrophobic recovery is governed by the dipole-dipole interaction of molecules of polymer and liquid. ► Cooling renders restoring of hydrophobicity of plasma irradiated films.