Modification of curcumin with a reactive UV absorber and its dyeing and functional properties for silk

Curcumin, derived from the ground roots of Curcuma longa L, has been extensively used to prepare colored and antibacterial textiles. Unfortunately, the applications of curcumin are limited due to its low water solubility, photo-sensitivity and poor fastness. In the present study, a novel water-soluble curcumin was synthesized by introducing a water-soluble reactive UV absorber into curcumin molecule, and applied in the dyeing and functional finishing of silk fabric. The modified curcumin showed good water solubility. The uptake of the modified curcumin by silk was more sensitive to the pH of dyebath than that of curcumin. Moreover, the silk fabric dyed with modified curcumin showed good color fastness (especially rub and light fastness), very good UV protection ability, and high antibacterial activity equivalent to that of the curcumin dyed silk, but its antioxidant activity was lower than that of the curcumin dyed silk. This study shows that the novel water-soluble curcumin can be synthesized through chemical modification and suitably applied to prepare multifunctional silk textiles. (C) 2016 Elsevier Ltd. All rights reserved.