Coloration of Apocynum venetum/cotton blends with an acid dye through combined pretreatment using cationic nanoparticles

Cationic copolymer nanoparticles were used to modify Apocynum venetum/cotton blended fabrics. The modified blends were then dyed using CI Acid Red 14. In order to enhance the colour performance, the effects of combined pretreatment using nanoparticles and sodium hydroxide (NaOH) or carboxymethylcellulose (CMC) or plasma were investigated. The results show that combined pretreatment with NaOH and nanoparticles improved the dyeing effect. The optimum concentrations of NaOH and nanoparticles were 100 and 2 g l^?1 respectively. In addition, using CMC to pretreat the fabrics could also improve the acid dyeing performance. However, the combination of plasma pretreatment and cationic nanoparticle modification produced the best colour performance for acid-dyed A. venetum/cotton blends. The dye exhaustion rate is highest (up to 95%) with plasma pretreatment. Scanning electron microscopy revealed that combined treatment with plasma and nanoparticles resulted in a far greater number of nanoparticles being deposited on the fibre surface. X-ray photoelectron spectroscopy indicated that the pretreatments with different procedures significantly changed the chemical components of the fibre surfaces. The aromatic rings of acid dye molecules covered the fibre surfaces after plasma and nanoparticle pretreatment and acid dyeing.