Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; Center of Excellence in Green Materials for Industrial Application, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Bangkok 10330, Thailand.
Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
Int J Biol Macromol. 2023 Jun 15;240:124412. doi: 10.1016/j.ijbiomac.2023.124412. Epub 2023 Apr 11.
On being exposed to water, cellulose paper swells and its mechanical properties become weak. In this study, natural wax with an average particle size of 12.3 μm extracted from banana leaves was mixed with chitosan to prepare coatings applied on paper surfaces. Chitosan efficiently dispersed banana leaf-extracted wax on paper surfaces. The mixed chitosan and wax coatings considerably influenced paper properties, including yellowness, whiteness, thickness, wettability, water absorption, oil sorption, and mechanical properties. The coating induced hydrophobicity in the paper, resulting in a significant increase in the water contact angle from 65.1 ± 7.7° (uncoated paper) to 123.2 ± 2.1°, and a decrease in water absorption by ⁓64 % to 52.6 ± 1.9 %. The coated paper demonstrated an oil sorption capacity of 212.2 ± 2.8 %, which was ⁓43 % greater than that of the uncoated paper (148.2 ± 5.5 %), and the tensile strength of the coated paper improved under wet conditions compared to the uncoated paper. Additionally, a separation of oil in water was observed for the chitosan/wax coated paper. Based on these promising results, the paper coated with chitosan and wax could be used for direct-contact packaging applications.
当暴露在水中时，纤维素纸会膨胀，其机械性能会变弱。在这项研究中，从香蕉叶中提取的平均粒径为 12.3μm 的天然蜡与壳聚糖混合，用于在纸表面制备涂层。壳聚糖有效地将香蕉叶提取的蜡分散在纸表面。混合的壳聚糖和蜡涂层对纸张性能有很大影响，包括黄度、白度、厚度、润湿性、吸水性、吸油性和机械性能。涂层使纸张具有疏水性，导致水接触角从未涂层纸的 65.1±7.7°显著增加到 123.2±2.1°，吸水率从 ⁓64%降低到 52.6±1.9%。涂覆的纸张具有 212.2±2.8%的吸油能力，比未涂覆的纸张（148.2±5.5%）高 ⁓43%，并且在湿条件下，涂覆的纸张的拉伸强度优于未涂覆的纸张。此外，还观察到壳聚糖/蜡涂覆的纸张在水中的油分离。基于这些有希望的结果，用壳聚糖和蜡涂覆的纸张可用于直接接触包装应用。
