Preparation of aminated polystyrene latexes by dispersion polymerization

The preparation and characterization of aminated polystyrene-based latexes as attainable by dispersion polymerization technique are reported. Mixtures of Boc-p-aminostyrene and styrene monomers at various compositions were co polymerized under dispersion conditions in 2-propanol/water 3:1 by volume i n the presence of alpha,alpha'-azobis(isobutyronitrile) as free radical ini tiator at 75 degrees C. Copolymer microspheres with uniform size distributi ons and average diameters comprised between 0.9 and 1.8 mu m were obtained. Aminated microspheres were obtained by the simple removal of the Boc prote ctive group under acidic conditions followed by neutralization, thus leadin g to p-aminostyrene/styrene copolymers. These chemical treatments when carr ied out under mild conditions (room temperature and dilute acid and basic s olutions), demonstrated to be efficient without causing any major alteratio n of the microspheres morphology. XPS analysis of the prepared microspheres showed an increase of NH2 groups with the increasing of the Boc-p-aminosty rene in the copolymer feed up to 10 mol %.