A Kinetic Method for Investigating the Structure of Adsorbed Polymer Layers

A kinetic method for investigating the adsorbed layer structure of a polymer (the copolymer of styrene and maleic anhydride) on a ZnO powder surface was developed, the method is based on the model of the heterogeneously inhibited polymerization of styrene ‘filled’ with ZnO powder. The polymerization is preceded by an induction period. The length of this period depends on the concentration of inhibiting sites (n) on the surface of ZnO. The adsorbed polymer blocks such inhibiting sites and the induction period decreases. This model was used to estimate n. A peak was observed in the experimental relationship connecting n with the amount adsorbed. This peak was interpreted as the critical concentration for conformation transition brought about by the interaction of the polymer chains at the surface. Below this concentration adsorbed macromolecules are considered as isolated chains at the surface. This state is characterized by the poor mobility of segments.