Thermodynamic characterization of the interaction behavior of a hydrophobically modified polyelectrolyte and oppositely charged surfactants in aqueous solution: Effect of surfactant alkyl chain length

• Tipo: Artigo em Revista Científica Internacional
• Data: 2005

Autores

Bai, GY (Autor) Outra; Nichifor, M (Autor) Outra; Lopes, A (Autor) FCUP; Bastos, M (Autor) FCUP

Revista

Título: Journal of Physical Chemistry B

Vol. 109

Páginas: 518-525

ISSN: 1520-6106

Editora: American Chemical Society

Indexação

ISI Web of Knowledge - 76 Citações

Scopus - 78 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-000-51E

DOI: 10.1021/jp046552b

Abstract (EN): We have used a precision isothermal titration microcalorimeter (ITC) to measure the enthalpy curves for the interaction of a hydrophobically modified polyelectrolyte (D40OCT30) with oppositely charged surfactants (SCnS) in aqueous solution. D40OCT30 is a newly synthesized polymer based on dextran having pendant N-(2-hydroxypropyl)-N,N-dimethyl-N-octylammonium chloride groups randomly distributed along the polymer backbone with degree of substitution of 28.1%. The employed anionic surfactants are sodium octyl sulfate (SC8S) and sodium tetradecyl sulfate (SC14S). Microcalorimetric results along with turbidity and kinematic viscosity measurements demonstrate systematically the thermodynamic characterization of the interaction of D40OCT30/SCnS. A three-dimensional diagram with the derived phase boundaries is drawn to describe the effect of the alkyl chain length of surfactant and of the ratio between surfactant and pendant groups on the interaction. A more complete picture of the interaction mechanism for D40OCT30/SCnS systems is proposed here.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8