Journal of Surfactants and Detergents最新文献

In this study, a new method was introduced to induce micellar transitions by using vesicles formed from mixed surfactants, which offer enhanced stability. Different physicochemical analysis methods were used to study the transition mechanism and the aggregation behavior of the mixed aqueous system composed of the double-chain cationic didodecyldimethylammonium bromide (DDAB) and a single-chain nonionic fluorinated surfactant undecafluoro n-pentyl decaoxyethylene ether (C₅F₁₁(EO)₁₀), by varying the fraction of DDAB, then the total surfactant concentration of DDAB/C₅F₁₁(EO)₁₀ mixed system at X_DDAB = 0.9. The obtained results indicated that the addition of the fluorinated surfactant C₅F₁₁(EO)₁₀ to the mixed system resulted in a reduction of the surface tension (γ) and a decrease in the Electrical conductivity (K). Furthermore, even at high total concentrations of the mixed system, the conductivity and charge density at the surface remained stable. As X_DDAB values increased, a higher degree of dissociation (α) was observed, along with negative values in the thermodynamic parameters of micellization (Δ$��G_{\mathrm{CMC}}^{°}�$, Δ$��G_{\mathrm{CVC}}^{°}�$, and Δ$��G_{\mathrm{ads}}^{°}�$), confirming the transition from micelles to vesicles. The dynamic light scattering (DLS) analysis revealed the formation of two stable types of aggregates at both low and high concentrations, as supported by the zeta potential (ζ). Upon increasing the concentration of surfactants, UV–Vis absorption measurements indicated that small spherical micelles grow into large multilamellar vesicles, as evidenced by an increase in turbidity and confirmed transmission electron microscopy images.

Amino acid surfactants have mild performance and are sourced from renewable biomass. Compared to classical surfactants, Gemini surfactants have superior properties. The amino acid Gemini surfactants are believed to be adopted more widely. The Gemini surfactant with tripeptide structure, sodium di(lauroyl glutamyl) lysine (DLGL), was prepared by amidation utilizing methyl laurate, glutamate and lysine and characterized by ¹H NMR, ¹³C NMR and MS. Additionally, the pKa value, surface activities, aggregation, foaming properties and emulsifying attributes of the DLGL surfactant in aqueous solution with varied pH values were examined. The results indicate that the protonation-deprotonation behavior of the DLGL surfactant is highly dependent on pH values. The surface tension, critical micelle concentration (cmc), foamability and foam stability exhibited superior performance at pH 6 and 7. Conversely, superior emulsifying ability was observed at pH 9 and 10. Moreover, the spherical vesicles were formed by the DLGL surfactant at pH 6, 7 or 8 while the micelles were generated at pH 9 or 10.

Current natural sources of mid-cut alcohol (MCA), a key ingredient in cleaning formulations, present several challenges. One solution is to use insect oils instead of palm kernel oil (PKO) or coconut oil (CNO). In particular, black soldier fly (BSF) larvae oil is a promising raw material that provides a sustainable, natural feedstock for MCA. The estimation of its PCF leads to strongly negative values, driven by a very low land use change. The fact that low-value by-products are upgraded by BSF larvae is an additional advantage and avoids any competition with food crops. This study shows that BSF larvae oil can be a drop-in replacement for PKO and CNO, leading to more sustainable ingredients for cleaning formulations. The technical proof of principle for the production of fatty alcohols has been demonstrated and up-scaling to large commercial volumes should be straightforward. A potential barrier to consumer acceptance is expected to be lowered in the future. In certain regions or applications, successful market entry may already be possible today.