The effect of structural variation of alcohols on water solubilization in nonionic microemulsions. 2. Branched alcohols as solubilization modifiers: Results and interpretation.


In this second part of a paper dealing with the effect of branched alcs. on solubilization, an attempt has been made to provide explanations of exptl. data related mostly to the system Brij 97/branched alc. + dodecane = 1:1 (by wt.)/water at 27 ± 0.2 °C . Applying the Hou-Shah mechanism it was shown that for many C4-C6 branched alc. isomers having one Me branch, solubilization behavior is readily interpreted by assuming control of the crit. radius, Rc. Two parameters, both included in the definition of the branching factor, Fb (which was treated in the first part of the paper), were also used to analyze solubilization data. The first, li, is defined as the distance from the free end of the alc. mol. to the Me branch. The second, d, is virtually NA, the chain length of the alc. When li \textgreater 3, the solubilization becomes dominated by the natural radius of curvature, R0. Also, we have suggested that for Rc-control, solubilization will be enhanced in direct proportion to the distance d-li whereas for R0-control, solubilization will increase with decreasing d-li. The validity of our assumptions was demonstrated in many cases. Some examples of the more complicated case of double branching (two Me groups along the alc. chain) were also analyzed. [on SciFinder(R)]
Last updated on 06/28/2020