Preparation of Janus structural colors with different hydrophilicity by spraying hydrophobic P(HFBMA-co-GMA) microspheres on polydopamine modified cotton fabrics

Structural colors forming by photonic crystal microspheres as a novel coloring method has received more and more attention in many fields. However, photonic crystal polymer microspheres usually do not have special functions, which limits their application. In this study, a novel polymer photonic crystal microspheres of poly (hexafluorobutyl methacrylate-co-glycidyl methacrylate) (P(HFBMA-co-GMA)) containing hydrophobic functional groups and reactive epoxy groups were synthesized. The structural colorized cotton fabrics with Janus characteristic of different colors and different hydrophilicity of two sides were prepared by spraying the functional P(HFBMA-co-GMA) microspheres on the polydopamine (PDA) modified cotton fabrics. P(HFBMA-co-GMA) microspheres can self-assemble into amorphous photonic crystals (APCs) with long-range disordered and short-range ordered on PDA modified cotton fabrics, showing crack-free and bright structural colors. The Janus structural colorized cotton fabrics with four different colors were obtained by spraying the P(HFBMA-co-GMA) microspheres with different particle diameters which were prepared by changing the molar ratios of HFBMA and GMA. The Janus structural colorized cotton fabrics have excellent flexibility, air permeability and colorfastness showing a good application prospect in functional textiles. This research provides a new strategy to prepare the functional structural color fabrics with Janus characteristic based on the synthesis of the functional polymer microspheres.