Interfacial behavior of randomly charged sulfonated polystyrene (PSS) at the air/water interface

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 313-314; pp. 660 - 665
• Main Authors: Seo, Young-Soo, Ahmad, Farhan, Shin, Kwanwoo, Song, Ju-Myung, Kim, Joon-Seop, Rafailovich, Miriam H., Sokolov, Jon, Satija, Sushil K.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2008; Elsevier
• Subjects: Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Langmuir monolayer; Polyelectrolytes; Polystyrene sulfonated acid; Surface physical chemistry; Polyelectrolytes; Langmuir monolayer; Polystyrene sulfonated acid; Gas liquid interface; Polyelectrolyte; Monolayer; Acids; Styrene polymer; Air water interface; Nanotechnology
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2007.04.095

Langmuir monolayers of randomly charged polystyrene sulfonated acid, PSSx, with various degrees of sulfonation (x) ranging from 4 up to 35% were studied. Three characteristic regimes of PSSx were determined, according to the balance between electrostatic and hydrophobic interactions in these ranges. Low charged PSS (4–5%) aggregates to irreversible films upon compression, leading to strong hysteresis. Moderately charged PSS (6–16%) is shown to less hysteretic. In contrast, highly charged PSS (35%) formed a reversible film due to dominant electrostatic interactions over hydrophobic interaction. Using in situ neutron reflectivity (NR) we observed that PSS with 35% sulfonation formed a highly stretched brush into the water subphase upon compression.