Abstract:
Admicellar polymerization is a process involving the polymerization of adsolubilized monomer within adsorbed surfactant aggregates on a substrate surface. This research focused on the effects of surfactant loading, monomer loading, and reaction time on the characteristics of the polymer formed by admicellar polymerization. The polymerization reactions were carried out on nonporous silica (Aerosil OX50) in cetyltrimethylammonium bromide (CTAB) aggregates using styrene monomer. The polystyrene was extracted from the surface of the modified silica using terahydrofuran (THF) solvent. CTAB adsorption and styrene adsolubilization at two different adsorbed surfactant concentrations (20 and 100 u mol/g) on the nonporous silica were studied. The modified silica has been examined by TGA and AFM. The extracted polystyrene was characterized by FTIR, TGA and GPC. The results showed that the reaction time for conducting admicellar polymerzation should not be shorter than two hours to obtain relatively high molecular weight polystyrene. The extent of the polystyrene film and amount of polystyrene forming on silica particles increased with increasing CTAB adsorption and adsolubilized styrene.
