Polymer-surfactant interfacial layer of polystyrene particles modelling by monolayer technique

The mixed monolayers of polydimethylsiloxane (PDS), sodium alkylsylfonate (E30), styrene (St) and polystyrene (PSt) in various combinations have been studied. The results obtained for two and three-component systems give an evidence of the specific interaction (possible complex formation) of PDS and E30 (responsible for polymeric and surfactant stabiliser factors, respectively) at the interfaces. The four-component monolayers of PDS/PSt/St/E30 have only one liquid-expanded state that is similar to the three-component systems (PDS/St/E30 and PDS/PSt/E30) and in contrast to the two-component systems (PDS/St and PDS/PSt). Moreover, in the case of PDS/PSt/St/E30 (1.0 mass%) system the monolayer parameters are almost not depending on the concentration of PDS (in the range of 1–10 mass%) that suggested as the most adequate model of the interfacial layer of polystyrene latexes. The following optimal ratios of both stabilisers: PDS 1–2% and E30 about 1% (calculated to St) have been found.