Complete Recycling of Textile Components From Cotton/Polyester Blended Fabrics.

The purpose of the study was to investigate the possibility of recycling textile components (especially cellulose) from cotton and polyester blended fabrics. The separation methods of intimately blended fibers developed were: (1) hydrolysis of polyester in NaOH solution or (2) dissolution of cotton in an N-methylmorpholine N-oxide monohydrate system. Complete separation was confirmed with thermal analytical methods such as differential scanning calorimetry and thermogravimetric differential thermal analysis. These thermal methods were found to efficiently determine accurate fiber contents in cotton/polyester blends and in rayon/nylon 6,6 composite fibers. In the recycling process for cotton/polyester blends, a 4M NaOH solution at boiling temperature and 2% NaOCl for an hour were optimum conditions for hydrolysis of polyester and bleaching of cotton residues respectively. Rheological characterization of 15% and 17% recovered cellulose solutions in the solvent system was carried out in a dynamic mechanical spectrometer which provided important information on conditions for spinning of high tenacity fibers. Lyocell fibers from the recovered cellulose solution were spun using an advanced capillary extrusion rheometer, and then dyed with a direct dye and a reactive dye