Measurement of Polymer Chain Depletion Layer in the Poly(vinyl alcohol)/Dimethyl Sulfoxide/Polystyrene Latex System by Dynamic Light Scattering

Abstract

The polymer concentration dependence of depletion layer was investigated by means of dynamic light scattering after the very small amount of polystyrene spherical latex particles was added into the matrix solution of poly(vinyl alcohol)(PVA)/dimethyl sulfoxide. At the dilute regime, the magnitude of depletion layer kept constant at the level of 63 +/- 3% of the radius of gyration of the corresponding PVA chain. Next, at the early semi-dilute regime of 1.5 <= C[eta]<= 3, polymer concentration dependence of the layer thickness delta was obtained as delta-C-0.8, and this experimental value was very close to theoretical one of -0.75. However it was observed above C[eta]> 3 that its thickness decreased abruptly, and this was ascribed to aggregation effect of latex particles which was driven by Oosawa type attractive interaction.