Abstract
The partition coefficient between water and the micellar phase of a barbituric acid, butobarbitone, has been determined in mixed aqueous solutions of two surfactants: sodium dodecylsulphate (SDS) and polyoxyethylene (23) lauryl ether (PEO 23). The partition coefficient of barbitone decreases when mixed micelles are formed. The effective composition of the mixed micelles is calculated from critical micelle concentration data obtained from surface-tension measurements, using the model of regular solutions. It is shown that small quantities of SDS in the mixed micelles have a large effect on the solubilization of butobarbitone; a larger quantity of POE 23 is needed to obtain the same results. This behaviour is interpreted in terms of interaction forces between the three components of the solution at the micellar surface. Inorganic salts such as Na 2SO 4 and MgSO 4 also decrease the partition coefficient of butobarbitone in POE 23 solutions. In the former case, the variation is a linear function of the mixed electrolyte/POE 23 mole fraction. In the latter case, a larger decrease is observed that is due to the interaction of the divalent ions with oxyethylene groups at the micellar surface.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
