Optimization And Functional Study Of PDA@SiO₂ Based Structural Color Materials

With the study of photonic structures in nature,structural colors have gradually become popular in various application fields due to their long-term use,high brightness,and angular characteristics.Artificial structural color materials are formed by combining inorganic materials,organic materials or polymer materials,imitating the photonic structure in nature.At present,structural color materials with low angle-dependent properties have broad application prospects in the field of wide viewing angles.However,such structural color materials are often prepared by self-assembly.During the self-assembly process,the particle solution in the colloidal suspension is subjected to various Due to the influence of factors,the color of the finally formed structural color material is uneven,which limits its broad application prospects.In this paper,a composite particle with a black shell on the surface and a certain roughness was synthesized based on silica particles,in order to prepare a structural color material with uniform surface color and low angle dependence,and to develop color,The chemical composition and mechanical stability were investigated.The main work involved in this paper is carried out from the following three aspects:(1)Using PVA or PVP as a surface modification substance to modify the surface of the silica particles.The experiment is mainly to use the modified St?ber method to prepare monodisperse silica particles with a large number of negative charges on the surface.The silyl hydroxyl group and the hydroxyl group on the surface of PVA or PVP are surface modified,and the addition ratio of the two,reaction time,reaction temperature and the number of washing times are controlled to control the modification degree of the silica particles.Scanning electron microscopy,infrared spectroscopy,Zeta potential and other characterization results show that the surface of the silica particles modified with PVA or PVP has discrete and randomly distributed convex structures.(2)Oxidative self-polymerization of dopamine is used to form melanoid,which is coated on the surface of PVA or PVP modified silica particles as a light-absorbing substance.The experiment is mainly to fully react dopamine and modified silica particles in a weak alkaline environment and normal temperature,and dopamine is oxidized and polymerized on the surface of the modified silica particles to form a black shell layer,and then the composite is good.The particles are prepared into colloidal suspensions and self-assemble into structural color materials.The characterization results of scanning electron microscope,laser particle size characterization,infrared spectrum,reflectance spectrum,optical image and other characterization results prove that the color material has the characteristics of uniform color and low angle dependence.The experimental results show that when the dopamine content is10% and the reaction p H value is 8.5,the structural color effect is the best.Different reaction substrates have little effect on the structural color.(3)Using y-methacryloyloxypropyltrimethoxysilane(KH570)as a modifier,hydrolyzing it in an acidic environment,mixing it into the composite particle suspension according to a certain proportion,and then co-assembling into a mechanically stable Good structural color material.The characterization results of optical micrograph,infrared spectrum and reflection spectrum show that when the addition amount of KH570 is 6%,the number of surface cracks of the structural color material is the least.