Preparation of carbon fiber substrates with structural colors based on photonic crystals

It is well-known that carbon fiber (CF) cannot be colored by traditional dyeing methods due to the strong inertness of fiber surface. With the increasing demand of consumers for fashion, colorful and diverse CF have attracted extensive attention. In this paper, inspired by the structural colors in nature, structural coloration of CF substrates by rapidly constructing photonic crystals (PCs) with structural colors was realized. The poly (styrene-methacrylic acid) (P(St-MAA)) colloidal microspheres prepared by a soap-free emulsion polymerization were used as building units to construct PCs. The influence of mass fraction of colloidal microspheres and the density of substrates on the structural colors of CF fabrics was investigated. The spraying method was also used to achieve structural color patterns on CF boards. Moreover, in order to improve the durability of structural colors, the resultant CF boards with structural colors were encapsulated with polydimethylsiloxane (PDMS). The results showed that according to Bragg diffraction law, P(St-MAA) colloidal microspheres with particle sizes of 213 nm, 235 nm, 255 nm and 307 nm can present PCs structural colors. When the mass fraction of the colloidal microspheres was 10%, brighter structural colors can be obtained on the CF fabrics with the higher density. The structural colors of patterns on the CF boards were bright and vivid. Furthermore, the colored CF boards encapsulated with PDMS could still maintain bright structural colors after rubbing and rinsing tests. The research will provide new approaches to ecological coloration of CF substrates.