Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
ACS Appl Mater Interfaces. 2023 Mar 8;15(9):12248-12260. doi: 10.1021/acsami.2c17886. Epub 2023 Feb 27.
Driven by the ever-growing awareness of sustainability and circular economy, renewable, biodegradable, and recyclable fiber-based packaging materials are emerging as alternatives to fossil-derived, nonbiodegradable single-use plastics for the packaging industry. However, without functional barrier coatings, the water/moisture vulnerability and high permeability of fiber-based packaging significantly restrain its broader application as primary packaging for food, beverages, and drugs. Herein, we develop waterborne complex dispersion barrier coatings consisting of natural, biodegradable polysaccharides (i.e., chitosan and carboxymethyl cellulose) through a scalable, one-pot mechanochemical pathway. By tailoring the electrostatic complexation, the key element to form a highly crosslinked and interpenetrated polymer network structure, we formulate complex dispersion barrier coatings with excellent film-forming property and adaptable solid-viscosity profiles suitable for paperboard and molded pulp substrates. Our complex dispersions enable the formation of a uniform, defect-free, and integrated coating layer, leading to a remarkable oil and grease barrier and efficient water/moisture sensitivity reduction while still exhibiting excellent recyclability profile of the resulting fiber-based substrates. This natural, biorenewable, and repulpable barrier coating is a promising candidate to serve as a sustainable option for fiber-based packaging intended for the food and food service packaging industry.
在可持续发展和循环经济意识不断增强的推动下，可再生、可生物降解和可回收的纤维基包装材料作为替代石油衍生、不可生物降解的一次性塑料的替代品，正在涌现。然而，如果没有功能性阻隔涂层，纤维基包装材料的高水/湿度敏感性和高渗透性会显著限制其在食品、饮料和药品的主要包装方面的更广泛应用。在此，我们通过可扩展的一锅法机械化学途径，开发了由天然可生物降解多糖（壳聚糖和羧甲基纤维素）组成的水性复合分散阻隔涂层。通过调整静电复合这一形成高度交联和互穿聚合物网络结构的关键要素，我们制备了具有优异成膜性能和可调节固含量的复合分散阻隔涂层，适用于纸板和模塑纸浆基材。我们的复合分散体能够形成均匀、无缺陷且完整的涂层，从而显著提高了油脂阻隔性能，并有效降低了水/湿度敏感性，同时还保持了纤维基基材出色的可回收性能。这种天然的、生物可再生的和可再制浆的阻隔涂层是一种很有前途的选择，可以作为面向食品和食品服务包装行业的纤维基包装的可持续替代品。
