Small-angle neutron-scattering study of alkyl polyoxyethylene sulfate micelles. Effect of the number of polyoxyethylene groups on n-dodecyl polyoxyethylene sulfate in deuterium oxide/water mixtures at 25.degree.C

Structure, Diffusivity and Linear Rheology of Sodium Ether Dodecylsulfate in Aqueous Solutions – (I)

“…The molecular weights of SLES micelles under low SLES and salt concentrations were found to vary between 27 000 (0.001 M NaCl) to 65 500 (0.15 M NaCl) yielding aggregation numbers, N agg , from 71 to 173, which are in agreement with those values obtained by Triolo et al [16]. The molecular weights of SLES micelles under low SLES and salt concentrations were found to vary between 27 000 (0.001 M NaCl) to 65 500 (0.15 M NaCl) yielding aggregation numbers, N agg , from 71 to 173, which are in agreement with those values obtained by Triolo et al [16].…”

“…(5) is therefore valid for l e /L 1, where large numbers of entanglements occur. Also the static viscosity η 0 as a function of SLES in the presence of 0.01%-0.001% (w/w) n-dodecanol at low salt (0.05 M, identical to Triolo et al [16]) is shown. (5) holds also for the condition l e /L 1.…”

“…If the breaking-recombination time, τ b , is considerable larger than τ e , the longest Rouse relaxation time for a chain of length l e , Eq. These experiments were conducted in light of recent studies by Triolo et al [16], who applied neutron scattering experiments and deduced hydrodynamic data therefrom. The correlation length, ξ, under good solvent conditions of the micellar aggregates, leads to (6): where b is the persistence length of the SLES micelle.…”

“…But above 5.0 · 10 −3 M SLES (C NaCl = 0.08-0.5 M) gelation started. (16): The values of the self-diffusion coefficient of SLES were obtained from plots of Γ vs. Q 2 , where Γ is the average decay rate for different SLES concentrations in the presence of salt.…”

A molecular dynamics investigation of structure and dynamics of SDS and SDBS micelles

“…Several techniques have been used experimentally to deduce the effective micelle surface charge (and thereby, the degree of counterion binding) including potentiometric measurements using ion-selective electrodes, 62-64 measurements of the solution electric conductivity, 65,66 electrophoretic mobility measurements, 66,67 light scattering measurements, 68,69 and small-angle neutron scattering measurements. 70,71 The binding is due to the long-range electrostatic forces, but there is a gradual change in the counterion-micelle interaction as the micelle surface is approached. Depending on the experimental technique, different aspects of the counterion-micelle interaction are probed, 72,73 and there is some degree of variation in the experimentally Na is reported to fall broadly in the range 0.4-0.8, in agreement with the calculated values.…”