In-Situ Observations of Growth Process of Polymer Particles and Antimicrobial Activity

Abstract

To clarify the growth mechanism of polymer particles, in-situ observations of growth process of soap-free emulsion polymerization of styrene were carried out using atomic force microscope. Polystyrene particles were swollen absorbing monomers in the bulk, and then solidified through the polymerization inside the particles with adsorption of the secondary newborn particles in the bulk like Ostwald’s ripening. According the growth mechanism, particle sizes were enabled to be enlarged by the coagulations during the polymerization with electrolyte.

To evaluate the influence of polymers synthesized through soap-free emulsion polymerization on the indicator microorganism Micrococcus luteus, styrene and styrene derivative monomers were polymerized using a cationic initiator. During the bioassay test, these polymers showed an inhibition zone against M. luteus. Hence, the supernatant containing polymers with lower molecular weights, which were toxic to M. luteus, obtained from soap-free emulsion polymerization should be treated carefully prior to its discharge to the environment.