Preparation and properties of double‐ or triple‐ chain surfactants with two sulfonate groups derived fromN‐ Acyldiethanolamines

Bis (sulfonate) types of amphipathic compounds with three long‐ chain alkyl groups were prepared by the reaction of N ‐ (long‐ chain acyl)diethanolamine diglycidyl ethers with long‐ chain fatty alcohols, followed by the reaction with propanesultone. The diglycidyl ethers were easily obtained from the corresponding N ‐ acyldiethanolamines and epichlorohydrin in the presence of a phasetransfer catalyst. The same types of compounds with two longchain alkyl groups were also prepared from Nacetyldiethanolamine according to similar procedures. All these new double‐ or triple‐ chain surfactants were soluble in water and showed much better micelle forming and ability to lower surface tension than general types of single‐ chain surfactants with one sulfonate group. The critical micelle concentration (CMC) and γ CMC values of the triple‐ chain compounds were still much smaller than those of the corresponding double‐ chain compounds with two common alkyl groups. The efficiency of adsorption at the water/air interface (pC 20 ) of these surfactants was very high. Their foaming properties, wetting ability toward a felt chip, and lime‐ soap dispersing ability were measured.