Fabrication of polymeric particles composed of two-dimensionally self-assembled nanoparticles by use of a microporous film as a template

Development of new self-organized preparation method of non-spherical nano or microparticles against the surface tension is a challenging and attractive field in material science. Already our research group has reported fabrication of several kinds of honeycomb-patterned microporous polymer films ("honeycomb films") by the "self-organization" process. By use of the honeycomb films, non-spherical particles composed of a particle array assembled the polymeric spherical nanoparticles were also prepared by self-organization processes. The preparation steps of the nanoparticles-assembled particles were: (1) formation of the two-dimensional single-layered arrays of polymeric spherical nanoparticles in each micropore of a honeycomb film by means of self-assembly of the nanoparticles, (2) connection of the all contacting nanoparticles in each micropore, then (3) peeling of the nanoparticles-interconnected particles from the honeycomb-nanoparticles composite structure. Number of the nanoparticles introduced into a micropore depended on the ratio of diameter of the honeycomb micropore to that of the nanoparticles. In the prepared non-spherical particle, alignment of the spherical nanoparticles was copied from that of the two-dimensional array of the nanoparticles assembled in the honeycomb micropore.