Self‐assembly of ionic amphiphiles on polyelectrolyte chains

The formation and structure of water‐soluble complexes of partly neutralized poly(acrylic acid) (PA) and poly(diallyldimethylammonium chloride) (PDADMAC) with oppositely‐charged surfactants [tetradecyltrimethylammonium bromide (C 14 AB) and sodium dodecyl sulfate (SDS)] have been studied by elastic and quasi‐elastic laser light‐scattering, high‐speed sedimentation and viscometry techniques. It was shown that minimum aggregation number ( n min ) of the surfactant ions in the complex micelle depends on the chemical structure of the polyelectrolyte. In particular, C 14 AB interacting with PA in dilute water solutions forms PA bound micelles with n min of 10 2 similar to spherical micelles formed by free C 14 AB. This is in contrast to soluble PDADMAC–SDS complex species, which are most probably vesicles, each containing ca 10 5 surfactant ions instead of 10 2 characteristic for free SDS spherical micelles. A shift from a dilute to a semi‐dilute solution regime with respect to the free PDADMAC results in drastic rearrangement of the PDADMAC–SDS complex structure. Copyright © 2003 Society of Chemical Industry