Integration of color construction and fibrillation reduction of lyocell in an ambient temperature environment

Abstract

Lyocell fiber is recognized as a sustainable regenerated cellulose fiber with indispensable color construction in extensive applications. However, the microfibers derived from fibrillation limit the coloration and application requirements because of the coexistence of adverse factors, including high temperature, humidity, and continuous friction in the color construction process. Herein, we report a static color construction method (SDM) under normal temperatures and pressures to reduce the formation of microfibers by avoiding continuous friction, high temperature, and humidity. Compared with the conventional dyeing method (CDM), the generated microfibers, total length of the microfibers, and the damaged area on the lyocell fibers decreased by 76.22%, 57.34% and 28.35%, respectively. Furthermore, a K/S value of 19.53 ± 0.41 and a fixation rate of 85.08% after soaping illustrated the superiority of SDM in color construction. Molecular simulations were employed to analyze the process of adsorption, air-drying, and coloration fixation. The calculated diffusion coefficient of NaOH in SDM is 18.46 × 10⁻⁷ cm² s⁻¹, which is 6.88 times that of CDM. The energy band structure, frontier molecular orbitals, and electrostatic potential distributions provide insights into the adsorption and fixation mechanisms of SDM. The proposed method for reducing microfibers by decreasing fibrillation in the coloration process presents a promising approach for developing sustainable textiles.