The aim of experiment was investigated of aggregation of three non-ionic classic surfactants type CiEj - heptylethylene glycol monodecyl ether (C10E7), heptaethylene glycol mono dodecyl ether (C12E7) and heptaethylene glycol monotetradecyl ether (C14E7) in D2O solutions by SANS method. The aggregation for such surfactant in water solutions dependence on concentration, temperature and molecular structure of surfactants. The size and shape of micelles in dilute aqueous solutions was determined by small angle neutron scattering (SANS). The SANS results were successfully analyzed with the aid of PCG 2.1 program from Graz University (Austria). For all investigated solutions c=0.17%, 0.5% and 1% and temperatures ( 10o,15o,20o,25o,30o and 35oC ) micelles are two axes oblate ellipsoids which increases slightly with increase concentration and temperature.
The small angle neutron scattering measurements for two surfactants C10E7 and C12E7 were carried out on the “Yellow Submarine” instrument at Budapest Neutron Centre. The sample to detector distance and the mean neutron wavelength were np.1.3m and 3.86A, respectively. The samples were placed in 2mm thick quartz cuvettes and then thermostated to ±0.5K. The scattering experiments covered the scattering vector, q (q=4psin (q/2)/l, q is the scattering angle, l is the wavelength), range 0.02-0.45Å-1.
The experiment with small angle neutron scattering method for surfactant C14E7 was made using a YuMO spectrometer of the IBR-2 on pulsed neutron source in the Laboratory of Neutron Physics, JINR, in Dubna (Russia). The Q range was 0.007 – 0.4 Å-1. The temperature within the cells was kept constant in a range of ± 0.5oC by means of a thermostat. Conversion of the scattered intensities into absolute differential cross-sections was done by using an internal calibration standard (vanadium).
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