Small-angle neutron scattering determining size distribution

Indirect techniques, such as conductivity measurements and the determination of the surface tension were carried out to get more information about the surfactant distribution during the polymerization and were applied to characterize the droplet or particle sizes before and after the polymerization without diluting the system [23]. As a powerful method small angle neutron scattering experiments were applied to characterize the droplet or particle sizes before and after the polymerization without diluting the system [23]. 

The structure of the AOT micellar system, as well as the state of water entrapped inside swollen micelles, have been characterized using different techniques, such as photon correlation spectroscopy (25), positron annihilation (26), NMR (27, 28), fluorescence (29-32) and more recently small angle neutron scattering (33). The existence of reversed micelles has been demonstrated in the domain of concentrations explored by protein extraction experiments. Their size (proportional to the molar ratio of water to surfactant known as wo), shape and aggregation number have been determined. Furthermore, the micelle size distribution is believed to be relatively monodisperse. 

A number of techniques have been employed to examine free volume properties of polymers. These include small angle x-ray scattering and neutron diffraction that have been used to determine denisty fluctuations to deduce free volume size distributions [4-7]. Photochromic labelling techniques by site specific probes have been developed to monitor the rate of photoisomerizations of the probes and from this deduce free volume distributions [8-11]. Additional probing methods used to probe voids and defects in materials such as scanning tunneling microscopy (STM) and... 

In principle, the dispersed phase size distribution can be determined from small-angle scattering experiments, using either X-rays or neutrons. Since a comparatively large volume is sampled by the incident beam, scattering... 

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