Response of block copolyelectrolyte complexes to addition of ionic surfactants

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2017-11, Vol.532, p.290-296
• Main Authors: Kaczmarek, Daria, Diget, Jakob S., Nyström, Bo, Gyulai, Gergő, Mészáros, Róbert, Gilányi, Tibor, Varga, Imre
• Format: Article
• Language: English
• Subjects: Block copolyelectrolytes; Exchange; Ionic surfactant; Polyelectrolyte complex (PEC); Stability
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2017.04.078

[Display omitted] •Surfactants can interact with oppositely charged polyelectrolytes bound in complexes.•Ionic strength has a major effect on the result of the PE/S exchange reaction.•By ionic strength and surfactant conc. release characteristics could be tuned. Polyelectrolyte complex formation of a long chain poly(sodium styrene sulfonate) (NaPSS) with short chain poly(vinylbenzyltrimethylammonium chloride) homopolymer (pVBTA) and block copolymers (PEG-b-pVBTA) was investigated. The effect of the PEG chain and the pVBTA block length was studied on the complex formation. Then the exchange of the complex bound pVBTA for cetyltrimethylammonium bromide (CTAB) was studied using complexes that contained excess of pVBTA segments. First we characterized the effect of ionic strength on the complex stability. Then we studied how the addition of CTAB affects the stability of the complexes with increasing ionic strength. We found that three ionic strength ranges could be distinguished. In the lowest ionic strength range, the formation of stable mixed complexes could be observed. In the intermediate ionic strength range the pVBTA polymer was mostly substituted by CTAB, leading to the aggregation and precipitation of the complexes under the investigated conditions. Finally, at the highest ionic strength the formation of equilibrium NaPSS/CTAB complexes could be hypothesized.