2009/03/31 by Jean‐François Berret, J. -F. Berret, Berret, J. -F. · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Advanced Polymer Synthesis and Characterization #FOS: Physical sciences #Pickering emulsions and particle stabilization #Soft Condensed Matter (cond-mat.soft) #Surfactants and Colloidal Systems #cond-mat.soft
paper · pdf · doi:10.48550/arxiv.0903.5432
7 pages, 9 figures, 2 tables paper accepted at Colloid and Polymer Science, 31-Mar-09
arxiv created 2009/03/31 · openalex publication_date 2009/03/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report the formation of colloidal complexes resulting from the electrostatic co-assembly between anionic surfactants and cationic polyelectrolytes or block copolymers. Combining light and x-ray scattering experiments with cryogenic transmission and optical microscopy, we emphasize a feature rarely addressed in the formation of the electrostatic complexes, namely the role of the mixing concentration on the microstructure. At low mixing concentration, electrostatic complexes made from cationic-neutral copolymers and alkyl sulfate surfactants exhibit spherical core-shell microstructures. With increasing concentration, the complexes undergo a sphere-to-cylinder transition, yielding elongated aggregates with diameter 50 nm and length up to several hundreds of nanometers. From the comparison between homo- and diblock polymer phase behaviors, it is suggested that the unidimensional growth is driven by the ability of the surfactant to self-assemble into cylindrical micelles, and in particular when these surfactants are complexed with oppositely charged polymers.