Summary: | The mesomorphic phase transitions of sodium stearate occurring between 23°C. and 200°C. were investigated by means of the nuclear magnetic resonance of the hydrogen nuclei in sodium stearate. The changes in the nuclear magnetic resonance line width as the temperature increased revealed three phase transitions. These are the supercurd-subwaxy transition at 114°C., the subwaxy-waxy at 130°C., and the waxy-superwaxy transition at approximately 165°C.. Since the nuclear magnetic resonance line width is reduced as molecular motion increases, a general explanation of the phase transitions has been attempted.
Stearic acid was also investigated by means of nuclear magnetic resonance at temperatures between 24°C. and 90°C.. Only one transition, the melting point at 70°C. could be detected. === Science, Faculty of === Chemistry, Department of === Graduate
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