Plasticizers Induced Formation of Microcapsules From Freeze Dried Polystyrene Microreactors

The article describes solvent induced preparation of polystyrene microcapsules from freeze-dried microreactors. An aqueous suspension of microreactors was exposed to a plasticizing solvent for a defined time period. Plasticizer molecules surround the polymer chains and repel the water molecules. It results in the movement of the monomers toward each other. The process leads to formation of microcapsules with a core-shell structure. For proof of concept, four plasticizing solvents, namely 1,4-dioxane, toluene, dichloromethane, and chloroform, were studied for annealing of the hollow particles. It was concluded that chloroform was the best plasticizer in terms of transforming microreactors into microcapsules