Kazutaka Koike

A Novel Route for Fabricating Metal‐Polymer Composite Nanoparticles with Phase‐Separated Structures

Au nanoparticles (NPs) and polymer composite particles with phase-separation structures were prepared based on phase separation structures. Au NPs were successfully synthesized in amphiphilic block-copolymer micelles, and then composite particles were formed by a simple solvent evaporation process from Au NPs and polymer solution. The phase separated structures (Janus and Core-shell) were controlled by changing the combination of polymers having differing hydrophobicity.

Localization of polymer-grafted maghemite nanoparticles in a hemisphere of Janus polymer particles prepared by a self-organized precipitation (SORP) method

Microspheric Janus particles with maghemite nanoparticles (NPs) in the hemisphere were investigated. Poly(styrene) (PS)-grafted maghemite NPs were embedded into the PS phase of a PS–poly(isoprene) (PI) Janus polymer particle prepared by a Self-organized Precipitation (SORP) method. The obtained Janus particles showed magnetic field responsive drifts and rotation in water. Potential application in electric paper pixels can be expected from the anisotropic magnetic response of the particle.