Ionomer-surfactant self-assembly in low-polarity solvents

• Published in: Macromolecular symposia. Vol. 106; no. 1; pp. 19 - 30
• Main Authors: Bakeev, Kirill N, Chugunov, Sergey A, Larina, Tat'yana A, Macknight, William J, Zezin, Alexander B, Kabanov, Viktor A
• Format: Journal Article
• Language: English
• Published: Hüthig & Wepf Verlag 01.04.1996
• ISSN: 1022-1360; 1521-3900
• DOI: 10.1002/masy.19961060105

A systematic study of complexation reactions of sulfonated polystyrene ionomers containing up to 5 molar percent of polar chain units with various oil-soluble surfactants is carried out in low-polarity organic solvents. Dipole-dipole attractions of the components lead to the formation of complexes characterized by limiting compositions and an unusual polymer-colloidal morphology of joint clusters and/or micelles. The limiting compositions (φ) for the complexes formed between ionomers and surfactant of the same charge (bis(2-ethylhexyl)sulfosuccinate sodium salt), or nonionic surfactants (primarily aliphatic amines) are equal to 15-30 surfactant molecules per one ionomer salt/acid group on average, with φ depending on the hydrophilic-lypophilic balance of the components, the initial aggregation state of surfactant and the nature of low-polarity solvent. Ionomersurfactant complexation is accompanied by disruption of self-contacts of ionomer salt/acid groups, leading to “unfastening” and expansion of the ionomer coils in dilute solution. The “driving force” of the ionomersurfactant complexation and the structure of the resultant complexes are discussed.