The structural formation of closely packed colloidal crystals on fibre and the effect of fibre surface functionality on crystalline structure

The effect of hydrophilicity and the charge of the fibre surface upon the formation of colloidal crystals on the fibre was investigated. Surface‐modified polyester fibre was prepared either by oxygen plasma treatment or with a sol‐gel method using 3‐aminopropyltriethoxysilane (APS). The surface‐modified polyester fibre was dip‐coated with 20 wt.% water suspension of uniform‐sized silica particles with a diameter of 300 nm and then it was dried. Hexagonal and square arrangements were observed for the particles deposited on the fibre surface by scanning electron microscopy (SEM). The crystallinity of deposited particles was estimated with the number ratio of arranged particles to all particles in the SEM image. On the plasma‐treated fibre, the crystallinity of deposited particles was 82% and the ratio of hexagonal arrangement to square arrangement was 3:1. On the APS‐treated fibre, crystallinity was 56% and the ratio was 1:8. The fibre‐fabricated colloidal crystal exhibited red colour on its surface and it had a peak wavelength of 637 nm in the reflection spectrum.