Synergism and Interfacial Property Study of Sodium Lauryl Ether Sulfate and Polysorbate 80 at the Air-Water Interface

The UV absorption spectra of six structurally related derivatives of anisole and veratrole, i.e., anisaldehyde, (E)-anethole, estragole, veratraldehyde, methyleugenol and (E)-methylisoeugenol, were recorded at various concentrations of the anionic surfactants, either sodium lauryl sulfate (SLS) or sodium lauryl ether sulfate (SLES) at T = 298 K. In addition, conductivity and density measurements were made for the SLS and SLES solutions to determine the volumetric properties of the studied surfactants. Next, using the W. Al-Soufi, L. Pińeiro and M. Novo model (APN model) including the pseudo-phase model for micellar solubilization, the values of micelle-water partition coefficients for each perfume-surfactant system were determined. In addition, the relations between the molecular structures of the solute and the head group of the surfactant and the value of the micelle-water partition coefficient as well as the octanol-water one were discussed.

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Environmental and energetic effects of cleaner production scenarios on the Sodium Lauryl Ether Sulfate production chain

Journal of Cleaner Production ◽

10.1016/j.jclepro.2019.118203 ◽

2019 ◽

Vol 240 ◽

pp. 118203

Author(s):

Alex R. Nogueira ◽

Maria da Graça C.B. Popi ◽

Claudia Cristina Sanchez Moore ◽

Luiz Kulay

Keyword(s):

Cleaner Production ◽

Production Chain ◽

Sulfate Production ◽

Sodium Lauryl Ether Sulfate ◽

Ether Sulfate ◽

Lauryl Ether

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Near infrared absorption spectroscopy for the quantification of unsulfated alcohol in sodium lauryl ether sulfate

Journal of Near Infrared Spectroscopy ◽

10.1177/0967033520963825 ◽

2020 ◽

pp. 096703352096382

Author(s):

SE Cunliffe ◽

PA Martin ◽

MR Baker ◽

O Mihailova ◽

PJ Martin

Keyword(s):

Gas Chromatography ◽

Least Squares ◽

Partial Least Squares ◽

Absorption Spectroscopy ◽

Near Infrared ◽

External Validation ◽

Sodium Lauryl Ether Sulfate ◽

Ether Sulfate ◽

Lauryl Ether ◽

Nir Absorption

Compositional variations in the surfactants used to produce personal care products result in significant challenges during large scale manufacturing, for example errors in product viscosity. Characterisation of the surfactant can be completed using chromatographic techniques however these are time consuming and impractical during real-time manufacturing. Near infrared (NIR) absorption spectroscopy with a fibre-optic coupled transmission probe is proposed as an in-line method of determining the levels of unsulfated alcohol in sodium lauryl ether sulfate (SLES). NIR absorption spectra in the region of 4000 – 12000 cm−1 were collected for a range of supplier samples at three temperatures. Gas chromatography - mass spectrometry was used as a reference technique to quantify samples of SLES and quantitative chemometric data analysis was used to produce partial least squares (PLS) calibration models for the prediction of surfactant composition. PLS regression was performed on the data in the spectral regions between 7509 – 5334 cm−1 using a range of data pre-processing techniques to identify the best model. Models were evaluated using root mean square error of cross validation (RMSECV) and residual predictive deviation (RPD) as the primary indicator of model accuracy and robustness. A partial least squares regression model using a generalised least squares weighting data pre-processing approach was found to be the most robust in regards to sample non-homogeneity and temperature, producing a model with an RMSECV = 0.094 w/w% and RPD = 4.03. The model successfully predicted the unsulfated alcohol mass percentage in an external validation of unknown samples with alcohol levels within the model limits of 0.7–2.2 w/w%. Spectra acquired at a resolution of 8 cm−1 with 32 scans take just 16 seconds to obtain, proving that NIR spectroscopy can successfully be applied as an alternative analytical method to gas chromatography for the determination of low level impurities in viscous surfactant systems.

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