Preparation and Structural Investigation of PMMA-Polystyrene ‘Janus Beads’ by Rapid Evaporation of an Ethyl Acetate Aqueous Emulsion

摘要

In this paper, the formation of microscopic polystyrene/poly(methyl methacrylate) Janus particles by using environmentally benign solvents and surface active agents is presented. Janus particles are formed by the rapid polymer phase separation that occurs when an oil-in-water suspension is allowed to dry. Biodegradable or bio-inert organic solvents and surface active agents are used. These solvents affect the particle morphology, which is studied in detail. The environmentally friendly solvent ethyl acetate can replace the more commonly used toluene for the preparation of Janus particles. Confocal Raman microscopy is used to visualize and analyze the phase separated Janus particles. Results indicate that the polystyrene hemisphere as minor component within the particle is covered with a thin PMMA layer on its surface. [DOI: 10.1380/ejssnt.2012.360]