Photonic Crystals with Chemically Reactive Polymer Colloids
Guofang Chen, St. John's College of Liberal Arts and Sciences, Department of Chemistry
Abstract: Polymer colloidal photonic crystals, which are ordered arrays of highly monodisperse polymer colloids, have demonstrated important potential applications in the fields of photonics, optics and sensing. The advantage of a chemically-reactive particles for the colloidal photonic crystal is that the use of chemically-reactive monomer can allow for easy chemical modification of the particle, which is capable of monitoring biorecognition and biochemical interaction at surfaces with visibly perceptible color change. In the presence of an analyte, the structure or optical properties of the photonic crystal change, leading to a change in its optical response, which is the foundation for the photonic crystal sensors. Here we developed a simple method based on surfactant-free emulsion polymerization technique with the dropwise addition of water-soluble initiators to synthesize highly monodisperse sub-micrometer latex particles from chemically-reactive monomer. With the as-prepared chemically reactive polymer colloids, photonic crystals were fabricated on the flat glass substrates, nonplanar substrates, inside fused-silica capillaries, and so on, which produce beautifully iridescent colors. Tough photopatterned photonic crystals were also prepared from such polymer colloids without using molds or grooves.