The Effect of Polymer Composition on the Molecular Adsorption Area of the Emulsifier

Conductometric coap titration and Maron's3 method of plotting polymer concentration vs. soap concentration is used to determine the molecular adsorption area (MAA) of potassium oleate in a number of polymer and copolymer latex systems. It is demonstrated that the MAA of potassium oleate increases in the series polystyrene→ polybutadiene→polystyrene-coacrylonitrile as well as in a series of polystyrene-coacrylonitrile systems with increasing acrylonitrile content in the polymer composition It is further demonstrated that the MAA increases with temperature at rates dependent on the chemical nature of the polymer systems. The composition induced increases in the MAA correlate as well with the polar nature of the polymer and are attributed to decreasing solubility of the lyophilic segment of the emulsifier chain in the polymer. Temperature induced MAA increases are attributed to Increasing mobility of the hydrophylic emulsifier segment in the aqueous phase.