The binding characteristics of aggregates formed between neutral polym
er (PVP) and anionic surfactant (SDS) are explored by light scattering
. As added SDS binds to PVP polymers, the mass increase of the scatter
ing aggregates is reflected in higher scattered intensity, so long as
electrostatic interactions due to the SDS charge (as reflected in the
second virial coefficient, A(2)) are suppressed by high ionic strength
. Although there is an equilibrium between bound and free SDS, the maj
ority of the scattering observed is due to SDS/PVP aggregates. These a
ggregates appear to consist of single PVP polymer chains with multiple
bound SDS micelle-type structures. Attempts are made to quantify the
binding of SDS to PVP in terms of the binding energy and binding volum
e, using both a model of scattering from multicomponent systems and a
model of the thermodynamics of the binding process. Additionally, the
saturation of PVP with SDS allows us to determine the stoichiometry of
the SDS/PVP aggregation and suggest a physical cause for the saturati
on.