In order to study the synergism between sulfonate and nonionic surfactant for lowering interfacial tension at oil/water interface,three branched alkylbenzene sulfonates and three polyoxyethylenated nonionic surfactants were used.The interfacial tensions of individual surfactants and their mixtures against a series of alkane homologues were measured.And the effects of hydrophilic-lipophilic ability of surfactant,mixing ratio,and salinity of aqueous phase on synergism were discussed.Experiment results showed ...