The hydrophobic hydration in aqueous solutions of allyl-substituted ammonium salts

The complex dielectric permittivity for the series of aqueous allyl-substituted ammonium salt solutions is investigated in microwave range (13-25 GHz) in a wide range of salt concentrations. The measurements were made at 298 K for diallylammonium and diallylmethylammonium trifluoroacetates and in the temperature interval 288-308 K for diallyldimethylammonium chloride. The values of dielectric constant εs and parameters of the dielectric relaxation process were calculated. The increase of relaxation time τ in comparison with pure water is observed for all investigated solutions. It indicates the decrease of orientation mobility of water molecules in the H-bond network upon action of allyl-substituted ammonium ions connected with hydrophobic hydration of these ions.