FABRICATION OF CORE-SHELL POLYMER MICROSPHERES OF P(St-AM) AND THE CORRESPONDING PHOTONIC CRYSTALS FILMS

The functional core-shell poly (styrene-acrylamide) latex microspheres with different diameters were prepared by one-step emulsion polymerization method by adjusting the dosage of the initiator. The core-shell structures and the diameters of latex microspheres were characterized by transmission electron microscope. The diameters of the as-prepared microspheres were 195,217,234 and 255 nm, respectively. The chemical composition of the microspheres was characterized by IR spectra,which testified that the polystyrene was wrapped by polyacrylamide successfully. The photonic crystals films of the as-prepared core-shell microspheres were fabricated by vertical deposition self-assembly method. The morphology of the as-prepared photonic crystals films were characterized by scanning electron microscope. The photonic stopbands were measured by reflectance and transmittance spectra. The results demonstrate that the polymer microspheres are in a face-centered cubic arrangement with a close-packed plane (111) oriented parallel to the substrate, and the stopbands of the photonic crystals can be varied when the diameters of the microspheres are different. In this work,photonic crystals films with different stopbands were obtained, and the stopbands occurred at 473, 515, 574 and 630 nm, respectively. The corresponding colors of the films were blue, green, yellow and red, respectively. It is very important for the development and application of photonic crystals.