Wetting Ability in Aqueous Mixtures of Amine Oxide with Anionic and Nonionic Surfactants

The wetting abilities of amine oxide surfactants (dodecyl dimethylamine oxide, DDMAO and dihydroxyethyl dodecylamine oxide, DDEAO), alcohol ether sulfate (AES), ethoxylated alcohols with different number of ethylene oxide units (AEOn, n = 3, 5, 7, 9) and mixtures of amine oxides with AES and AEOn were measured according to the canvas descending method. The effect of surfactant concentration, surfactant type, number of ethylene oxide unit and temperature on the wetting ability of mixed systems has been analyzed. The results show that the wetting abilities of DDEAO and DDMAO are better than those of AES, AEO9 and AEO3, and similar to those of AEO5 and AEO7. For all mixed systems, the optimum wetting ability appears at equal weight mixtures in the weight ratio range investigated. These mixtures show a synergistic effect. Higher temperatures imply higher wetting ability in aqueous mixtures of DDMAO with AES and AEO3 at weight ratio = 1 : 1.