Preperation of monodispersed SiO2 particles for electrostatic self-assembly of SiO2/PEI thin film with structural colors on polyester fabrics

The monodispersed SiO2 particles with perfect sphericity and desired particle sizes were synthesized by an improved Stober method. The particle sizes and size distribution of colloidal silica could be regulated by adjusting reaction temperature, reaction time, and the concentrations of NH4OH, H2O and TEOS. Dynamic light scattering particle size analysis and SEM analysis confirmed a narrowly distributed particle size and good sphericity of the synthesized SiO2 nanoparticles. The structural colors of silica/polyethyleneimine (SiO2/PEI) thin film fabricated on polyester fabrics were governed by SiO2 particle size, assembly cycles and viewing angles, and the origin mechanism of the structural colors was based on the thin film interference theory. The resultant polyester fabrics showed vivid structural colors changing with the change in viewing angles, displaying a biomimetic variable coloration effect on textiles.