"One-for-all" on-demand multifunctional fluorescent amphoteric polymers achieving breakthrough leather eco-manufacturing evolution

The traditional leather industry holds a significant position within the global manufacturing sector, contributing both economically and socially. Relentless multifunctional material-innovation for sustainable leather-manufacture is the only pathway to completely solve the current environmental concerns including widescale discharge of waste and chemicals. Herein, we address these limitations by developing a scalable and sustainable "one-for-all" strategy based on a synthetic multifunctional fluorescent amphoteric polymer (referred to as AADs) through free radical polymerization and amidation grafting reactions achieving a breakthrough leather eco-manufacturing evolution. The resulting AADs effectively integrate the all-round multifunctionalities of tanning, retanning, fatliquoring, regulable color dyeing, and anti-counterfeiting marking into leather. The interfacial multi-point cross-linking of AADs with natural collagen fibers in leather enhances crust-leather with a shrinkage temperature (Ts) exceeding 77 degrees C and standard-compliant mechanical properties, scratch resistance, and fluorescence for anti-counterfeiting purposes through the creation of distinctive patterns such as barcodes and QR codes. The formative covalent-bonding between the two significantly enhances dye fixation, resulting in leathers with superior durability against rubbing and washing. This innovative process not only reduces the processing time from 1095-2360 min to 500 min and cuts down leather chemical usage by 47.5-74.8%, but also lowers water consumption by 82.6-90% through streamlining multiple primary procedures into a single process. Furthermore, AADs robustly minimize human health risks by 55-71.6% and decrease greenhouse gas emissions by 38.2-52.4% and environmental impacts by 49.3-58.8%, lowering the carbon and environmental footprint of leather production. The innovation of the "one-for-all" process based on emerging multifunctional materials aligns with global sustainability goals, fundamentally aiding the leather industry in transitioning towards more sustainable practices.