STRUCTURE AND DYNAMICS OF THE POLYELECTROLYTE COMPLEX-FORMATION

The complex formation in the oppositely charged linear and flexible po lyelectrolytes: quaternized poly(vinylpyridinium) (QPVP) and poly(sodi um styrenesulfonate) (NaPSS) was investigated by static and dynamic li ght scattering (LS), flow birefringence (FB), and viscometry over a wi de range of mixing ratios 0.003 less than or equal to m less than or e qual to 0.9. NaPPS/QPVP systems in N-methylformamide + 0.01 M KBr gene rated complexes with fractal geometries. The observed clusters were st able and had average dimensions R-g approximate to R-h approximate to 1000 Angstrom at low and high mixing ratios. As the mixing ratio appro ached m = 0.4, which corresponds to the gel point, the number and the dimensions of clusters grew to R approximate to 1500-3000 Angstrom wit h a corresponding increase of the fractal parameter d approximate to 3 . According to FB data, the axial ratio of the clusters at the gel poi nt m = 0.4 was p = L/d = 1.07, which supports a model with spherical s hape.