Study On The Preparation Of The Dye-loaded Structural Units Of The Photonic Crystals And The Related Structural Coloration Applications On Textiles

As a kind of environmental friendly biomimetic coloration ways,photonic crystals attract much attention from domestic and foreign scholars.However,some random defects such as missing particles,uncontrolled orientation are produced during the colloid self-assembly inevitably,and mixtures of phases or dislocations,which decrease the reflectivity of the photonic band gap and makes the structural colors become much lighter.Based on this,in this paper,dye-loaded structural unit and corresponding nanospheres inks were prepared by loading black dye onto the surface of nano spheres,and the vivid photonic crystal structure on white textile substrates are fabricated by ink-jet printing self-assembly.The research includes the following three aspects:(1)The dye-loaded structural units were designed and prepared.And the surface morphology,particle size,monodispersity,electronegativity,stability and adsorption model of structural units were systematically studied;(2)Specifically,the components of the nanospheres inks were prepared,the effective method to inhibit the "coffee ring" was provided;(3)The printing self-assembly process and mechanism of nanospheres ink on textile substrate were studied.And the methods to improve binding strength of the photonic crystals on textile substrate was proposed.The results showed that:(1)Dye-adsorbed on surface structural units were prepared by absorbed of black reactive dyes are on the external surface of PSt microspheres under the electrostatic interaction.Particle size of structural units is in 240-310 nm.The resultant nanospheres are in uniform size and good sphericity.The adsorption of reactive dyes in the solid(microsphere surface)and liquid(microsphere emulsion)is consistent with the Langmuir adsorption model basically.(2)P(St-BA-MAA)nanospheres were stained with disperse black dyes by thermal swelling,then the internal dye-coated structural units were prepared by seed emulsion polymerization to clated seed emulsion.Dye-coated structural unit that particle size is 185-314nm were prepared by regulating the concentrations of St,MAA,APS and solid content in seed emulsion polymerization.(3)By regulating the amount of dyes,ink pH,surface tension,and adding suitable "coffee ring" inhibitors,the prepared nanospheres ink with excellent spray effect were applied to digital ink-jet printing self-assembly.(4)By printing self-assembly technology,three-dimensional face-centered cubic(FCC)photonic crystal structure could be constructed on white textile substrate.During the ink jetp rinting self-assembly process,the structural units are assembled from the gas-liquid interface,and the evaporation rate of the solvent at the edge of the ink droplet is faster than that of the intermediate region.After the surface of the textile substrate undergoes a series of color changes following the blue shift law,will obtain a uniform and bright structural color on the fabric,with an iridescent effect.(5)The binding strength of the photonic crystals on textile substrate was improved by introducing the NMA which could be thermal-crosslinking monomer into the nanospheres ink.