Prediction of Critical Micelle Concentration Using a Quantitative Structure–Property Relationship Approach

✍ Scribed by P.D.T. Huibers; V.S. Lobanov; A.R. Katritzky; D.O. Shah; M. Karelson

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 132 KB
• Volume: 187
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1996.4680

✦ Synopsis

domain (head) of the surfactant influence the cmc. The two Relationships between the molecular structure and the critical contributions are counteracting, with a lower cmc for a larger micelle concentration (cmc) of anionic surfactants were investihydrophobic domain and a higher cmc for a larger hydrogated using a quantitative structure-property relationship apphilic domain. The current study attempts to define quantitaproach. Measured cmc values for 119 anionic structures, representtive measures for these two counteracting contributions that ing sodium alkyl sulfates and sodium sulfonates with a wide variwill apply over a wide range of anionic surfactant structures.

ety of hydrophobic and hydrophilic structures, were considered.

The best multiple linear regression model involved three terms

Previous correlations of the cmc. Linear relationships (descriptors) and had a correlation coefficient of R 2 Å 0.940. Very between the logarithm of the cmc and the size of a homologood correlations (R 2 Å 0.988) were obtained using three descripgous series of surfactants have been known for decades. tors for a subset of 68 structures, with structural variation only Examples of such dependencies as a function of alkane carin the hydrophobic domain. From the descriptors used in these bon number are summarized in Table 1. The limitation of regressions, one can conclude that the cmc is primarily dependent applicability of these relationships is that the coefficients on the size (volume or surface area) of the hydrophobic domain must be recalculated for each homologous series. More genand to a lesser extent on the structural complexity of the surfactant eral relationships would be of value in establishing specific molecule.