| Texto completo | |
| Autor(es): |
Vitorazi, L.
[1, 2]
;
Ould-Moussa, N.
[2]
;
Sekar, S.
[3]
;
Fresnais, J.
[4]
;
Loh, W.
[1]
;
Chapel, J. -P.
[3]
;
Berret, J. -F.
[2]
Número total de Autores: 7
|
| Afiliação do(s) autor(es): | [1] Univ Estadual Campinas, UNICAMP, Inst Chem, Campinas, SP - Brazil
[2] Univ Paris 07, UMR CNRS 7057, F-75205 Paris - France
[3] Univ Bordeaux, UPR CNRS 8641, Ctr Rech Paul Pascal, F-33600 Pessac - France
[4] UPMC, CNRS, UMR 7195, Physicochim Electrolytes & Nanosyst Interfaciaux, F-75252 Paris - France
Número total de Afiliações: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | SOFT MATTER; v. 10, n. 47, p. 9496-9505, 2014. |
| Citações Web of Science: | 49 |
| Resumo | |
Recent studies have pointed out the importance of polyelectrolyte assembly in the elaboration of innovative nanomaterials. Beyond their structures, many important questions on the thermodynamics of association remain unanswered. Here, we investigate the complexation between poly(diallyldimethylammonium chloride) (PDADMAC) and poly(sodium acrylate) (PANa) chains using a combination of three techniques: isothermal titration calorimetry (ITC), static and dynamic light scattering and electrophoresis. Upon addition of PDADMAC to PANa or vice-versa, the results obtained by the different techniques agree well with each other, and reveal a two-step process. The primary process is the formation of highly charged polyelectrolyte complexes of size 100 nm. The secondary process is the transition towards a coacervate phase made of rich and poor polymer droplets. The binding isotherms measured are accounted for using a phenomenological model that provides the thermodynamic parameters for each reaction. Small positive enthalpies and large positive entropies consistent with a counterion release scenario are found throughout this study. Furthermore, this work stresses the importance of the underestimated formulation pathway or mixing order in polyelectrolyte complexation. (AU) | |
| Processo FAPESP: | 10/52411-6 - Interaction of anionic block copolymers with cationic surfactants and inorganic nanoparticles: structural and thermodynamic characterization |
| Beneficiário: | Watson Loh |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |