Temperature effects on surface activity and application in oxidation of toluene derivatives of CTAB-SDS with KMnO4

Abstract

The γ cmc values of CTAB-SDS decrease from 63⋅67 mN/m at 10°C to 36⋅38 mN/m at 90°C, slightly lower than those of either CTAB or SDS. Correspondingly, the CMC of CTAB-SDS decreases almost by half. The increase of surface activity of CTAB-SDS can be attributed to the relatively weak electrostatic interaction at high temperature, which is supported by the increase of solubility of CTAB-SDS with rise in temperature. Catalytic effect on oxidation of toluene derivatives with potassium permanganate follows the order CTAB-SDS > SDS > CTAB. This is not caused by the dissociative effect of CTAB-SDS with low surface activity at low temperature, as seen from the fact that almost all oxidative products can be retrieved for different toluene derivatives and surfactants by mimicking the conditions of reaction. In the emulsifications of toluene derivatives at 90°C, the time that turbid water layers of surfactant solutions take to become clear is the same as that of the catalytic effect on oxidation of toluene derivatives. Thus, it can be inferred that surfactants can improve the oxidation yields of toluene derivatives by increasing the contact between two reacting phases.

High polymer/surfactant ratio in the seeded semicontinuous heterogeneous polymerization of vinyl acetate

“…The cmc of the SDS at 60°C was determined as 7.7 mM·l −1 , which is within the range of values reported in the literature for SDS in different solvents and temperatures [16–18].…”

Production and characterization of novel self-assembling biosurfactants from Aspergillus flavus

“…Biosurfactants caused disturbance in balance of adhesive and cohesive forces resulting in sliding down of liquid droplet (Lv et al 2010;Biria et al 2013). It is pertinent to note that surface activities and CMC values of synthetic surfactants SDS and CTAB, calculated in this study also matched those reported in literature (Abood and Ajam 1985;Tang et al 2006). Anti-adhesiveness of the biosurfactant is important for its antiviral and biofilm removing abilities (Janek et al 2012;Gudina et al 2013).…”

CTAB promoted synthesis of Au nanorods – Temperature effects and stability considerations

“…4). As reported by Tang et al, the critical micelle concentration (CMC) for pure CTAB goes from 1.14 mM at 10°C to 1.07 mM at 90°C [20]. These values are almost two orders of magnitude lower than the CTAB concentrations used in this work.…”