Homogeneous complex solution formed through interpolyelectrolyte complexation of poly(acrylamide-acrylic acid) with poly(acrylamide-dimethyldiallylammonium chloride) in aqueous media

Interpolyelectrolyte complexation of two oppositely charged polymers in aqueous media is a new approach for modifying polymer solutions, especially for enhancing solution viscosity. In this paper, a homogeneous complex solution was prepared through complexation of poly(acrylamide-acrylic acid) [P(AM-AA)] containing adjustable anionic content and poly(acrylamide-dimethyldiallylammonium chloride) [P(AM-DMDAAC)] containing adjustable cationic content. The interactions between these two oppositely charged polymers and the viscosity of the complex solution were studied by means of visible spectrophotometry, UV spectrometry, fluorescence spectrometry, dynamic light scattering and viscometry. The experimental results show that a P(AIM-AA)/P(AM-DMDAAC) homogeneous complex solution exhibits characteristics different from those of its constituents, due to intermacromolecular interactions. Compared to the two component polymer solutions, ie P(AM-AA) solution and P(AM-DMDAAC) solution, the complex solution has a new peak around 210nm in its UV spectrum, lower fluorescence intensity and larger hydrodynamic radius, and hence higher solution viscosity. (C) 2000 Society of Chemical Industry.