Characterization techniques resolution size ranges

In theory, the SPOS technique can also be used to characterize the main, submicron portion of the PSD of polymer emulsions, rather than just their oversize tails. In practice, however, these ultrahigh-resolution techniques are confined to measuring the latter feature of the PSD, because of their limited detection threshold (sensitivity) - typically 0.5 jxm for commercially available SPOS sensors (LS method) of traditional design. However, the new high-concentration SPOS-LS technique is able to provide accurate quantitative information (no. of particles per milliliter) over most of the size range encompassed by the PSD - that is, down to 0.2 jxm, or even smaller. This qualitative improvement in sensitivity and working particle concentration (on the order of 10 particles per milliliter) allows SPOS to become one of the most important tools for characterizing the quality and stability of submicron polymer emulsions. 

The hard-ray diffraction technique allows a fast characterization of the lattice distortions for sample size in the centimeter range or more. The spatial resolution is low, but this technique showed the predominance of excess screw dislocations to accommodate the torsion deformation in all deformed crystals. A negligible contribution of edge dislocations was evidenced, which is consistent with the loading conditions. 

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