Adsorption of poly(tert-butylstyrene)/poly(styrenesulfonate) diblocks on polystyrene latices from water is reported and interpreted with scaling theories to demonstrate the effects of ionic strength and curvature on layer thickness. The adsorbed amount increases with ionic strength from no added salt to 0.1 M, forming a dense polyelectrolyte brush. The influence of particle radius on layer thickness is correlated quantitatively via the Daoud−Cotton model, but the effect on surface coverage is obscured by uncontrolled aspects of surface chemistry. Decreasing the ionic strength dramatically increases the dimensions of polyelectrolyte micelles and adsorbed layers; the sensitivity, while strongly coupled with curvature, is overestimated by all existing theories. A simple scaling theory that accounts for electrostatic excluded volume more appropriately captures the trends qualitatively.

Fluorescence emission techniques were applied to the study of aqueous solutions of a hydrophobically modified polyelectrolyte, a block copolymer of sodium poly(styrenesulfonate) (NaPSS) and poly(tertbutylstyrene) (PtBS). At low concentrations, the spectrum of NaPSS/PtBS is essentially identical to that obtained for NaPSS homopolymer. Above a certain concentration, which we identify as corresponding to the critical micelle concentration (cmc), substantial differences are noted in the spectra. Specifically, an increase in the intensity of the excimer peak at 330 nm is observed for the diblock solution relative to the homopolymer solution. The cmc is estimated to be in the range of 2 × 10 -7 to 2 × 10 -6 g/g for the diblock.