Abstract:

Abstract Surface tension, dynamic surface tension and molecule exchange energy in mixed monolayer formation(ε) and mixed micellization(ε_m) were determined, for binary mixtures of a multidegree polymerized dodecyl polyglycoside C₁₂G_1.46 with C₁₂E₃S(trioxyethylenated dodecyl sulfonate), C₁₂TAC(dodecyl trimethylammonium chloride), BE-6(hexa-oxyethylenated trisilaxane surfactant), and TMN-6(hexa-oxyethylenated-2,6,8-trimethyl-nonanol), respectively, in 0.1 mol/L NaCl solution at 25 ℃. From the results obtained two conclusions are drawn: (1) C₁₂G_1.46 is more surface-active than pure C₁₂G₁ and C₁₂G₂, which is interpreted by the energy results calculated by using MM2 force field method; (2) for C₁₂G_1.46/BE-6 and C₁₂G_1.46/TMN-6 systems, the mixed monolayer formation is prior to the mixed micelle formation, in which ε-ε_m<0 and the dynamic surface tensions reach the meso-equilibrium with 15 s; while for C₁₂G_1.46/C₁₂E₃S and C₁₂G_1.46/C₁₂TAC systems, surface adsorption and micellization processes occurred at the same time, in which ε-ε_m≥0 and the meso-equilibrium are reached within about 50 s.

Key words: Alkylpolyglycoside; Molecule exchange energy; Binary surfactant system; Surface adsorption; Micellization