Preparation of ag-embedded polystyrene nanospheres and nanocapsules by miniemulsion polymerization
Haeng-Deog Koh1, Mohammad Changez, Jung-Pil Lee
1Department of Materials Science and Engineering, Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712, Korea; Department of Nanosystems Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712, Korea.
Abstract:
An isopropyl myristate (IPM) biocompatible oil and an IPM solution of dodecanethiol-capped Ag nanoparticles (NPs, 4.5 nm) were used as hydrophobes to suppress the Ostwald ripening of monomer/hydrophobe miniemulsified droplets in a surfactant-stabilized water phase. The formation of non-IPM-encapsulated nanospheres (48 nm) and IPM-encapsulated nanocapsules (90 nm) were precisely controlled by using a water-soluble and an oil-soluble initiator, respectively, in the presence of a pure IPM as a hydrophobe in miniemulsion polymerization. Well-defined PS nanospheres, on which surfaces were coated with Ag NPs (Ag/PS nanospheres, 65 nm), and nanocapsules encapsulating both NPs and IPM liquid phase (Ag-IPM/PS nanocapsules, 115 nm) were made by replacing the hydrophobe from pure IPM with Ag/IPM solution. These nanostructures were characterized by transmission and scanning electron microscopes.
