Colloidal properties of ?-sulfonated fatty acid methyl esters and their applicability in hard water

Effects of Temperature and Humidity History on Brittleness of α-Sulfonated Fatty Acid Methyl Ester Salt Crystals

“…Figure 8 shows the FT-IR spectra of samples A, C, and F at 20 . Samples A and C had a single peak at 1468 cm 1 1 33, 34 .…”

“…Fujiwara et al constructed a concentrationtemperature phase diagram in a water-MES system and revealed aggregation states 1 . Investigating low-concentration regions, they carried out thermodynamic analysis of micelle formation, solubilization of oleic acids as a model of sebum, and stability in hard water.…”

“…In the case of oleic acids, they showed that the solubilization ability of the MES was 1.6-1.9 times higher than that of linear alkylbenzene sulfonate sodium salts LAS , a common anionic surfactant. By using static and dynamic light scattering they revealed that the number of MES micelles was slightly lower than that of LAS micelles, whereas the solubilization ability of MES micelles was approximately 2.4 times higher than that of LAS micelles, owing to easier coalescence of MES micelles than LAS micelles 1,2 . Regarding stability in hard water, it has been shown that MES performs better than LAS and alkyl sulfonate sodium salts AS , which precipitate in hard water as divalent metallic salts 1 .…”

“…By using static and dynamic light scattering they revealed that the number of MES micelles was slightly lower than that of LAS micelles, whereas the solubilization ability of MES micelles was approximately 2.4 times higher than that of LAS micelles, owing to easier coalescence of MES micelles than LAS micelles 1,2 . Regarding stability in hard water, it has been shown that MES performs better than LAS and alkyl sulfonate sodium salts AS , which precipitate in hard water as divalent metallic salts 1 . In addition, MES have other special features like excellent detergency 3 5 , favorable biodegradability 6 8 , and high stability against enzymes 9 , and therefore, MES have been used as ecofriendly washing detergents.…”

In vitro Analysis of the Effect of Alkyl-Chain Length of Anionic Surfactants on the Skin by Using a Reconstructed Human Epidermal Model

“…The alkyl-chain length causing the strongest tissue damage was different for AS and MES, and this difference was likely due to the structural difference of the effective alkyl-chain length in AS and MES. Fujiwara et al reported that the cmc of MES was lower than that of AS 10 . Since the methylester group and the methine group in the MES head group contribute to hydrophobicity, the effective alkylchain length of MES is one or two carbon atoms larger than that of AS when they have the same alkyl-chain length, R. Thus, this is the reason why the skin tissue damage of MES with alkyl-chain length of C8 was similar to that of AS with the alkyl-chain length C10.…”