Ulf Olsson

We present a first time-resolved deuterium NMR study on wormlike
micelles under shear. For the investigation, a micellar system made of
soybean phosphatidylcholine (lecithin), D2O, and cyclohexane was
studied in the concentrated regime, in the vicinity of the
isotropic/nematic transition but positioned in the equilibrium
isotropic phase. The D2O dispersed in the micellar core was used as a
probe to study the relaxation of a shearing-induced nematic phase back
to the isotropic liquid state, after cessation of shear. The whole
process was followed through time-resolved deuterium spectra and was
characterized by a continuous decrease of the measured quadrupolar
splitting, proportional to the nematic order parameter.