关键词: 光子晶体, 胶体微球, 涂料, 结构生色, 虹彩效应, 结构稳定性

Abstract: Bionic structural coloration based on photonic crystals is an eco-friendly coloring technology that eliminates the need for chemical colorants and produces no wastewater discharge. Photonic crystal coatings represent the most commonly used and effective approach for preparing bionic photonic crystal structural color coatings demonstrating versatility across various substrates. At present there are two primary methods for preparing photonic crystal coatings:1 the indirect method based on photonic crystal pigments;2 the direct method based on colloidal nanospheres.The indirect method utilizing photonic crystal pigments involves first preparing photonic crystal pigments from colloidal nanospheres followed by constructing photonic crystal coatings using these pigments.However this approach suffers from issues such as a lengthy preparation process complex fabrication procedures and difficulties in balancing color vividness and colorfastness in practical applications.This study proposes a method for directly constructing a self-forming film coating system based on hard-core-soft-shell structured PS@P(MMA-BA) colloidal microspheres and applies this coating system to effectively prepare photonic crystal structural color coatings with high structural stability brightness and saturation on various substrates.The results show that the PS@P(MMA-BA) colloidal nanospheres with uniform size and good sphericity can be synthesized using a semi-batch emulsion polymerization method.By concentrating the colloidal microsphere suspension and constructing the coating system through rotor evaporation,the resulting coating system exhibits high color saturation and brightness along with excellent dynamic recoverability and storage stability.Through blade coating and stepped heating treatment the issue of relatively dim structural color coatings caused by the high viscous resistance of the soft P(BA-MMA) shell layer which impedes the highly ordered arrangement of the hard PS core into a face-centered cubic packing structure is resolved.This enables the rapid and efficient preparation of non-close-packed photonic crystal structural color coatings where the hard core serves as the supporting framework and the soft shell fuses as the filling medium achieving a synergistic optimization of high color saturation and structural stability.By adjusting the particle size of the PS@P(MMA-BA) nanospheres photonic crystal coatings of different colors can be prepared which can be applied to structural color coatings on the surfaces of various substrates all demonstrating significant iridescent effects and exhibiting excellent tolerance in different environments.The photonic crystal coatings prepared in this study exhibit angle-dependent color-changing effects significantly enhancing their visual appeal.Moreover the overall color and luster of the coatings are beautiful and elegant meeting the demands of high-end coating design.These coatings hold broad application prospects in fields such as textiles and automotive coatings providing new ideas and approaches for the practical application of photonic crystal structural coloration technology in the coating industry.

Key words: photonic crystal, colloidal microsphere, coating, structural coloration, iridescent effect, structural stability