A "Taiji-Bagua" inspired multi-functional amphoteric polymer for ecological chromium-free organic tanned leather production: Integration of retanning and fatliquoring. (15th October 2021)

• Record Type: Journal Article
• Authors: Liu, Xinhua; Wang, Wanni; Wang, Xuechuan; Sun, Siwei; Wei, Chao
• Is Part Of: Journal of cleaner production. Volume 319(2021)
• Publication Date: 2021-10-15
• Subjects: Organic chrome-free -- Wet finishing materials -- Amphoteric polymer -- Dual-functional -- Retanning -- Fatliquoring; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2021.128658
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Comprehensive promotion of chrome-free organic tanning system has become an inevitable trend for cleaner production in leather manufacturing industry. However, the imbalance of interface charge between conventional anionic wet finishing material and organic tanned leather leads to poor quality of finished leather. Herein, a novel amphoteric polymer P (AA-AM-C12 DM) as retanning and fatliquoring dual-functional wet finishing material was prepared by free radical polymerization using acrylic acid (AA), acrylamide (AM), and (2-methacryloyloxyethyl) dodecyl ammonium bromide (C12 DM) as raw materials in an aqueous system and further applied in TWS organic tanned leather. Comprehensive structural and performance characterization of P (AA-AM-C12 DM) confirmed the presence of amphoteric groups and hydrophobic long chains in its structure. Number average molecular weight and isoelectric point were determined to be 6396 g mol −1 and 5.16, respectively. The physical and mechanical properties, morphology of the P (AA-AM-C12 DM)-treated leather, and their reactivities to anionic dye were investigated. The effect of hydrogen bond and ionic bond, which resulted from reactions between the carboxyl groups, amide groups, cation N + in P (AA-AM-C12 DM), and the pendant amino groups, hydroxyl groups, carboxyl groups from collagen fibers, benefitted in enhancing the physical and mechanical properties of crust leather and their reactivity to anionic dye. Moreover, P (AA-AM-C12 DM) showed remarkable environmental benefits compared to the commercial fatliquor, by significantly promoting dye absorption as high as 96.57%. These findings provide a potential application of P (AA-AM-C12 DM) to coordinate well with an ecological chrome-free organic tanning system, significantly promoting the cleaner production in the leather industry. Graphical abstract: Image 1 Highlights: P (AA-AM-C12 DM) polymer with retanning and fatliquoring dual-function was prepared. The preparation process was completed in an aqueous system. P (AA-AM-C12 DM) has remarkable environmental benefits by promoting dye absorption. The polymer simplifies process, saves chemicals, and reduces wastewater discharge.