The mechanical performance in the wet state needs to be significantly improved and the intrinsic functionalities should be fully utilized to promote the replacement of fossil-based plastics with renewable biobased materials. We demonstrate a leather-inspired approach to produce multifunctional materials with a high wet strength that is based on tannin-induced precipitation of gelatin grafted onto surface-modified cellulose nanofibrils (CNF). The leather-inspired CNF-based films had a wet tensile strength of 33 MPa, a Young's modulus of 310 MPa, and a strain at failure of 22%, making the wet materials stronger than, for example, dry conventional low-density polyethylene and more ductile than paper-based food packaging materials. The tannin-containing films displayed excellent antioxidant and UV-blocking properties, rapidly scavenging more than 90% of added free radicals and absorbing 100% of light in the UV-B/UV-C range. This work illustrates the prospect of combining renewable materials in a leather-inspired approach to form wet strong and multifunctional films with potential application in food packaging.

中文翻译：

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具有高湿强度的抗氧化剂和防紫外线皮革启发的纳米纤维素薄膜。

湿态下的机械性能需要显着提高，应充分利用其内在功能，以促进可再生生物基材料替代化石基塑料。我们展示了一种皮革启发性的方法来生产具有高湿强度的多功能材料，该方法基于丹宁酸诱导的接枝到表面改性纤维素纳米纤丝（CNF）上的明胶沉淀。受到皮革启发的CNF基薄膜的湿拉伸强度为33 MPa，杨氏模量为310 MPa，破坏时的应变为22％，使湿材料比干燥的常规低密度聚乙烯和比纸质食品包装材料更具延展性。含单宁的薄膜具有出色的抗氧化剂和紫外线阻隔性能，快速清除超过90％的添加自由基，并吸收100％在UV-B / UV-C范围内的光。这项工作说明了将可再生材料以皮革为灵感的方法结合起来以形成湿的强韧多功能薄膜的前景，并有望在食品包装中应用。