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Weiche Materie Poster: Do., 13:00–15:30 D-P348
Influence of pH and alcohols on aggregation of nonionic surfactant C14E7
in heavy water solutions study by SANS method.
Aldona Rajewska 1,2
1 Institute of Atomic Energy, 05-400 Swierk - Otwock, Poland – 2 Joint Institute for
Nuclear Research, Laboratory of Neutron Physics, 141980 Dubna, Russia
The classic nonionic surfactant C14E7 (heptaethylene glycol monotetradecyl ether)
were investigated at two constant concentrations of 0.17 %, 0.5 % in heavy water solutions
at room temperature without and with add of alcohols ethanol and glycerol with
used the small angle neutron scattering method. The influence of pH on aggregation in
these solutions were investigated, too. All SANS measurements were performed on the
time-of-flight spectrometer MURN of the pulsed reactor IBR-2, JINR, Dubna, Russia.
Neutrons were used in wavelength range of 8 x 10 −3 to 0.4 ˚A −1 .
For the measurements quartz cells of thickness 2 mm were used. They were sealed to
prevent evaporation during the experiment. Up to 15 such cells were placed in a sample
holder, and the temperature within the cells was kept constant in a range of ± 0.5 ◦ C by
means of a thermostat. Conversion of the scattered intensities into absolute differential
cross-sections was done by using an internal calibration standard (vanadium). For all
samples D2O was used as solvent in order to achieve good contrast conditions.