Activator speeds cotton bleaching

Abstract

Textile manufacturers often bleach cotton fabric to remove color impurities before dyeing. This process commonly involves oxidizing the natural colorants in cotton fibers with hydrogen peroxide under strong alkali conditions, and it can be accelerated by steaming the fabric after the chemicals are applied. But those harsh processing conditions can damage cotton fibers, and steaming times of as much as 50 minutes consume large amounts of energy. Researchers from Jiangnan University and Nantong University report a method for bleaching cotton fabrics that achieves optimal whiteness in just four minutes of steaming time, with very little fiber damage (ACS Sustainable Chem. Eng. 2018, DOI: 10.1021/acssuschemeng.8b00912). The method relies on a bleach activator, N-[4-(triethylammoniomethyl)benzoyl]caprolactam chloride (TBCC). Bleach activators react with hydrogen peroxide in aqueous solution to form peracids that are active at lower temperatures than hydrogen peroxide. Unlike other reported bleach activators, T...