Effects of various additives on the cloud point of dodecyl polyoxyethylene polyoxypropylene ether

Effects of various additives, including electrolytes, alcohols and organic acids, polymers, and ionic and nonionic surfactants, on the cloud point of dodecyl polyoxyethylene (5) polyoxypropylene (4) ether nonionic surfactant aqueous solutions are investigated. The salting-out electrolytes decrease the cloud point while salting-in electrolytes increase it. Most alcohols and organic acids can lower the cloud point except for methanol and ethanol. The polymers form complexes with the surfactant and decrease the cloud point. The added surfactants can be inserted into the micelles of the nonionic surfactant and form mixed micelles, thus raising the cloud point.