Adsorption of amphiphilic polysaccharides onto polystyrene latex particles

Adsorption properties of hydrophobically modified carboxymethylpullulans (HMCMP) with different degree of modification of alkyl chains (C8) onto polystyrene latex particles have been investigated. Hydrophobic interactions between the grafted alkyl chains and the surface are responsible for the adsorption of these polymers. Their adsorption isotherms are Langmuir type, therefore, there is only a monolayer of adsorbed polymer chains. Variations of plateau adsorbed amounts and adsorbed layer thicknesses show a competition between the number of anchors (alkyl chains) and size of loops. Desorption of adsorbed polymer chains has been tested in three different media (0.1 M NaCl, pure water and 0.01 M NaOH). The greater desorbed amount has been obtained in 0.01 M NaOH (hydrolysis of ester bonds).