Characterization of new gemini surfactant micelles with phosphate headgroups by SANS and fluorescence spectroscopy

Two series of bisphosphate surfactants having different hydrophobic tails a nd variable number of spacer methylene groups have been synthesized. Detail ed small-angle neutron scattering studies were carried out with their aqueo us solutions to study their micellar properties. For some of these new surf actants, critical micellar concentrations and micropolarities were also det ermined. It has been found that the micelles were ellipsoidal for surfactan ts with short spacers having C12H25 hydrophobic tails. However, the corresp onding surfactants having C16H33 chains and similar m-values afforded micel les that were disk-like and rod-like. (C) 1999 Elsevier Science B.V. All ri ghts reserved.