UV-Visible Light Attenuation and Reusability of Sonochemically-Applied Zinc Oxide (ZnO) Nanoparticle-Treatment on Unstarched and Starched Ramie Fabric

Zinc oxide nanoparticles were incorporated onto ramie fabrics via sonochemical application method to enhance its UV-visible light attenuation. Ramie fabric is very thin and does not shield the wearer of ramie clothing from direct sunlight. Applying both in-situ and ex-situ treatment methods via using bath sonication, the nanoparticles were applied onto plain ramie and starched ramie fabric. X-ray Diffraction showed that the nanoparticles present on the fabric have the wurtzite structure of ZnO. The average crystallite size of the ZnO were estimated to be 12–14 nm. Scanning Electron Microscopy images showed that these crystallites aggregated to a size of 160–740 nm. For the light attenuation tests, a mercury light source was passed through the ramie fabric samples, and the UV-Vis spectra of transmitted light is recorded. Results revealed that starching does not affect the UV-Vis attenuation of plain ramie fabric. Unstarched in-situ treated samples exhibited the highest UV-Vis attenuation even at the end of the 21st wash cycle. The starched ex-situ treated samples consistently had the least UV-Vis attenuation compared to all the other treated samples. Furthermore, the unstarched in-situ treated samples had better wash durability over both the unstarched ex-situ treated samples and the starched in-situ treated samples. Based on the results, it is concluded that the best method to produce a UV-visible light attenuating ramie fabric with zinc oxide nanoparticles and retain this light attenuating property even after multiple washing is to apply the zinc oxide nanoparticles on unstarched ramie fabric via in-situ treatment method.