聚醚型非离子型表面活性剂的混合表面膜 Ⅰ.Triton X-100、Triton X-305与硬脂酸、十六醇、聚丙二醇的二元混合膜

Mixed Monolayers of Polyether-Type Nonionic Surfactants I. Binary Mixture of Polyoxyethylated i-Octyl Phenols with Stearic Acid, Cetyl Alcohol and Polypropylene Glycol

非离子型表面活性剂在乳化、起泡、分散、润湿、洗涤,润滑、防锈、抑制水蒸发等许多重要过程中有着广泛的应用.这些应用的关键往往在于界面膜性质的有效控制.

The film pressure vs.area isotherms of the single and mixed monolayers of Polyethylene glycol mono(i-octylphenyl)ethers(Triton X-100 and Triton X-305),polypropylene glycol(PPG),stearic acid(SA)and cetyl alcohol(CA)on the surface of 40%NaNO_(3)aqueous solution have been determined at 20℃.For the equimolar mixtures of TX 100/SA,TX 100/CA,TX 305/SA and TX305/CA,the experimentalπ-αcurves show small positive deviations from calculated average curves based on simple additivity rule.As Shah and Shiao had suggested that the expansion of mixed monolayers arising from unequal chain length is presumably caused by the thermal motion of the hydrocarbon chains.For the equimolar mixtures of TX100/PPG and TX305/PPG,the experimentalπ-αcurves show negative deviations from calculated average curves.Based on the previously proposed model that the polyethylene glycol chain may be forced to enter water phase under pressure,the results can be explained rationally.From a simple analysis of the shape of the compression curves of the surface film,we reach the conclusion that in all of mixed monolayers in this work,the two components are miscible on the surface of water.