2019 Volume 92 Issue 10 Pages 299-303
A facile and novel approach of preparing monodisperse polystyrene (PS) particles having a “cylindrical” shape was discovered. The proposed synthetic method involved dispersion polymerization of the spherical PS particles stirred in a polyvinylpyrrolidone (PVP) aqueous solution for several hours using a magnetic stirrer. In the presence of PVP, the spherical PS particles deformed into cylindrical shapes following stirring; however, the particles did not deform in the absence of PVP. The deformation rate of the particles was affected by the molecular weight of dissolved PVP. This stirring method is not only highly efficient and provides high yield, but is also applicable to other materials such as polymethyl methacrylate (PMMA). Moreover, cylindrical polystyrene particles were applied as a particulate stabilizer to prepare a Pickering emulsion of decane (oil)/water. Unlike the spherical particles that are typically used in Pickering emulsions, the cylindrical particles enhanced the emulsion’s stability (up to 1 year). Furthermore, the cylindrical particulate stabilizer enabled a stable emulsion across a wide range of pH. Notably, unique adsorption behavior of the cylindrical particles on an oil droplet was observed, in which the cylindrical particles connected head to head to form a network that acted as a cage around the oil droplet.
