16577-10-9Relevant academic research and scientific papers
Smectic liquid crystals from supramolecular guanidinium alkylbenzenesulfonates
Mathevet, Fabrice,Masson, Patrick,Nicoud, Jean-Francois,Skoulios, Antoine
, p. 2248 - 2254 (2002)
A homologous series of guanidinium alkylbenzenesulfonates from ethyl to tetradecyl were synthesized and characterised. Their thermotropic polymorphism was investigated by polarizing optical microscopy, differential scanning calorimetry, and dilatometry. The structure of the smectic liquid crystal phases obtained at high temperature with the compounds from octyl to tetradecyl was analysed by X-ray diffraction. The supramolecular assembling of the ionic species inside the smectic layers was investigated by infrared spectroscopy.
PROPRIETES PHYSICI-CHIMIQUES DE N-ALKYL P-BENZENE SULFONATES ALCALINS: TEMPERATURE DE KRAFFT ET CONCENTRATION CRITIQUE MICELLAIRE
Rouviere, Jacques,Faucompre, Bernard,Lindheimer, Marc,Partyka, Stanislas,Brun, Bernard
, p. 309 - 314 (2007/10/02)
The Krafft points (Tk) and the critical micellar concentrations (c.m.c.) on the alkali salts of n-alkyl-p-benzene sulfonates have been measured by solubility and conductivity experiments.For the sodium compounds, we observe a linear relationship between log10cmc and n the number of carbon atoms in the alkyl chain of the surfactant, a linear relationship between the Tk of the homologous surfactants studied and n.The substitution of sodium counter-ion by another alkali, decreases the Krafft point which seems to be correlated to the hydratation of the counter-ion.These data permit us to know the Tk and c.m.c. of homologous series of various amphiphiles.By treating the formation of micelles as analogous to phase separation, the determination of the variation of c.m.c. with temperature has been studied, these results have been converted into, enthalpy and free energy of micellization and these have been compared with corresponding values obtained from literature data.
