| 초록 |
Formation and morphology of silver nanoparticles were investigated in incompatible PVP/PEO blend where PVP formed circular islands in PEO sea. Interestingly, we observed ring formation of silver nanoparticles at interface between the PVP and the PEO domains. It is known that reduction of silver ions into metallic silver in PVP is much faster than that in PEO, resulting in the fact that the silver ion concentration is lower in the PVP domain than the PEO one. Therefore, the concentration gradient across the interface between the PVP and the PEO domains is developed, which induces the diffusion of silver ions into the interface. However the diffusion rate of silver ions in glassy PVP is much lower than that in the PEO. Therefore silver ions will be accumulated at the interface, subsequently reducing to metallic silver nanoparticles and forming a ring of silver nanoparticles. |
