LIGHT-SCATTERING AND SMALL-ANGLE NEUTRON-SCATTERING FROM POLYELECTROLYTE SOLUTIONS - THE SUCCINOGLYCAN

The static properties of succinoglycan salt-free solutions are discussed in the semidilute range of concentration as revealed by light scattering and small-angle neutron scattering (SANS). As expected the results show the existence of a broad scattering intensity peak in the investigated range of polyelectrolyte concentration C-p and momentum transfer q in both light scattering and SANS. The positions of these peaks scale roughly as C-p(1/2) when using both techniques in different ranges of C-p. Contrary to flexible polyelectrolytes such as polystyrene sulfonate (NaPSS), the values of the peak positions obtained using light scattering and those obtained from SANS do not-follow a master curve, although they have a C-p(1/2) behavior. This new and unexpected result could be explained on the basis of the stereoregularity and the semirigid nature of the succinoglycan polysaccharide which favors a change in linear mass density as the concentration increases.