Low‐temperature bleaching of cotton fabric with a binuclear manganese complex of 1,4,7‐trimethyl‐1,4,7‐triazacyclononane as catalyst for hydrogen peroxide

Abstract

Bleaching of cellulose fabric with hydrogen peroxide is traditionally conducted under alkaline conditions at high temperature, which leads to greater energy consumption and fibre damage. In this study, a binuclear manganese complex of the ligand 1,4,7‐trimethyl‐1,4,7‐triazacyclononane as the catalyst for hydrogen peroxide bleaching was synthesised via a simplified method. Low‐temperature bleaching of cotton fabric with the manganese complex and the effect of key bleaching variables on the bleaching performance were investigated. Hydrogen peroxide could be catalysed to bleach cotton knitted fabric at a temperature as low as 60 °C by incorporating the complex in the bleaching solution. The whiteness index of the fabric bleached at low temperature was lower than that of fabric bleached at high temperature, but the bursting strength retention is much better for the fabric bleached at low temperature. The low temperature is energy‐saving and has environment‐friendly advantages over the traditional high‐temperature method.