ИСТИНА

The aqueous solution properties of a wide range of amphiphilic block and graft copolymers of n-butyl acrylate (nBA) and acrylic acid (AA) was investigated using tensiometry, fluorometry, DLS, and SANS. The critical micelle concentration (cmc), the micellar size as well as the aggregation number strongly depend on the fraction of AA units, pH, and topology. At pH > 6 the polymers have high cmc values (> 0.1 g/L) and predominantly form unimolecular micelles with PnBA core and PAA corona. With decreasing pH, cmc values decrease and micelles are formed with the aggregation number and the hydrodynamic radii increasing with decreasing pH and AA content. Above cmc, graft copolymers form micelles with significantly lower aggregation numbers than block copolymers of the same composition.