Amphiphilic block copolymers can be spontaneously assembled and crosslinked around inorganic nanomaterials to form permanent core-shell nanostructures without the need for covalent attachment of the polymer to the particle. Single-walled carbon nanotubes (SWNTs) and Au nanoparticles were encapsulated within micelles made from amphiphilic poly(styrene-block-acrylic acid) (PS-b-PAA) or poly(methylmethacrylate-block-acrylic acid) (PMMA-b-PAA) copolymers. The structure and physical properties of these nanomaterials were precisely determined by the characteristics of the self-assembled components. The encapsulated nanomaterials can be spontaneously assembled into 1D chains by a morphological transition of polymer micelles from sphere to worm-like structure. Because the crosslinked micelle shells are topologically linked to nanoparticles rather than chemically bound, the encapsulation approach to core-shell nanostructures might be used to add polymer shells to nanomaterials that lack effective surface chemistries.
Youngjong Kang is an Assistant Prof. of Chemistry at Hanyang University, Korea. He received his Ph.D. degree in Materials Chemistry at the University of Minnesota in 2005 with Prof. T. Andrew Taton. He undertook a postdoctoral fellowship with Prof. Edwin L. Thomas at MIT from 2005 to 2007.