A novel way for the alignment of lyotropic hexagonal and Lα phases in magnetic fields
An ionically charged Lα phase can be prepared without shear by mixing a small amount of meth-ylformiate to an L3 phase from alkyldimethylaminoxide, hexanol and water. If the structural transformation induced by the hydrolysis reaction of the ester is carried out in the presence of a high magnetic field, a macroscopically aligned lamellar phase is obtained. The alignment process was studied by 2H NMR measurements. The NMR measurements allow the determination of the rate constant of the alignment process and at the same time they can be used to control the degree of macroscopic orientation of the system. In addition, we studied the formation and the alignment process of a hexagonal lyotropic mesophase. The hexagonal phase can be prepared without shear by protonating a highly concentrated alkyldimethylaminoxide solution. The reaction that is used for the protonation is the hydrolysis reaction of methylformiate to formic acid and methanol.
Key wordsLamellar phase Hexagonal phase Alignment process 2H NMR measurements
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