Small angle scattering neutrons

Fig. 9 Density profiles of PEE-PSSH micelles for varying salt concentrations. The profiles were obtained by a combination of static and dynamic light scattering, small-angle neutron scattering and cryo-TEM [49]...

The pH-induced micellization of a DMAEMA-6-DEAEMA diblock copolymer has been studied in detail using dynamic light scattering, small-angle neutron scattering, and fluorescence spectroscopy [166], The DMAEMA constitutes the corona of the micelle, whereas the DEAEMA forms the core. Pyrene was used as a probe to determine the nature of the DEAEMA blocks. It was shown that the hydrophobicity of the micellar cores increased progressively as the solution pH was adjusted from pH 7 to 9. In the presence of an electrolyte, it was possible to observe both individual chains (unimers) and micelles under certain conditions. The critical micellization pH depended on both the copolymer concentration and also the background electrolyte concentration. 

Several methods may be applied to obtain the micellar size and shape of block-and-graft copolymers light scattering, small-angle X-ray scattering, small-angle neutron scattering. 

Lodge [102] and Norman [103] reviewed the use of scattering techniques in the characterization of polymers, particularly block copolymers. Static and dynamic light scattering, small-angle neutron and X-ray reflectivity were analyzed and emphasis was placed on their similarities and differences. 

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