Cationic cellulose nanofibers/chitosan auxiliary-dominated win-win strategy for paper yarn with superior color and physical performances

• Published in: Carbohydrate polymers 2024-04, Vol.330, p.121833-121833, Article 121833
• Main Authors: Guo, Xiaohui, Yang, Rendang, Wang, Yang, Ni, Shuzhen, Cheng, Chen, Fu, Danning, Sheng, Jie
• Format: Article
• Language: English
• Subjects: adsorption; Cationic cellulose nanofibers; Cellulose; cellulose nanofibers; chitosan; cohesion; color; dyeing; dyes; hydrogen; Neutral salt-free dyeing; Paper yarn; pulp; tensile strength
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2024.121833

The colored and high-saline effluents during the traditional dyeing process poses serious environmental challenge. In our study, an eco-friendly cationic cellulose nano-fiber/chitosan (CCNF/CS) binary versatile auxiliary was designed for the neutral salt-free dyeing and physical enhancement of paper by mixing with pulp simply. Profiting from the rich cationic binding sites of CCNF/CS (Charge density: 3749.67 μmol/g), under near neutral conditions (pH = 6.2), the maximum adsorption capacity of anionic GL (Direct fast turquoise blue GL) on paper with 0.5 % CCNF/CS reached 1865.06 mg/g with a desirable evenness (45.5 % and 92.1 % higher than that of CCNF and NaCl group, respectively), and the dye uptake was up to 97 %. The spontaneous adsorption behavior was aligned with the pseudo-second-order and Langmuir models, with a primary physical mechanism enhanced by chemical forces. The combination of strong electronic attraction, hydrogen bonding, and n-π stacking effects granted CCNF/CS an enhanced proficiency in anionic dye adsorption. In addition, the tensile strength of the resulting paper yarn with 0.5 % CCNF/CS increased to 52.47 MPa under the optimal parameters, deriving from the CCNF/CS-induced inter-fiber cohesion. Overall, our research provided a green promising approach for the innovative neutral salt-free dyeing and mechanical enhancement of paper. [Display omitted]