Improved mechanical and antibacterial properties of polyvinyl alcohol composite films using quaternized cellulose nanocrystals as nanofillers
Improved mechanical and antibacterial properties of polyvinyl alcohol composite films using quaternized cellulose nanocrystals as nanofillers
复制标题
使用季铵化纤维素纳米晶作为纳米填料改善聚乙烯醇复合薄膜的机械和抗菌性能
DOI：
10.1016/j.compscitech.2022.109885
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发表时间：
2022-12-22
影响因子：
9.1
通讯作者：
Xie, Yanjun
中科院分区：
文献类型：
--
作者：
Meng, Lina;Li, Jiangwei;Xie, Yanjun
纤维素纳米晶体（CNC）是一种天然的、可再生的、生物相容的材料，已被广泛用作聚合物复合材料中的新型可持续增强纳米填料。我们提出了聚乙烯醇（PVA）/CNC复合材料与改善的机械性能和抗菌性能，使用基于CNC的纳米填料。以6-溴己酰氯为原料，通过表面酯化反应制备了表面酯化CNC（ECNC）。随后，通过引入具有不同碳链长度（C8-C16）的叔氨基，将ECNC的烷基溴基团转移到季铵基团以制备季铵化CNC（ECNC-Qn）。然后，将ECNC-Qn与PVA基体共混，通过溶剂浇铸法制备PVA/ECNC-Qn纳米复合膜。不同的功能，包括光传输，机械性能，并对革兰氏阳性菌（金黄色葡萄球菌）和革兰氏阴性菌（大肠杆菌）的抗菌活性进行了研究。与纯PVA膜相比，PVA/ECNC-Qn纳米复合膜具有更高的拉伸强度和更高的抗菌活性。PVA/ECNC-Qn纳米复合膜的最大拉伸强度和断裂伸长率分别为45.4 MPa和318.4%，比纯PVA膜分别提高了37.2%和94.3%。此外，ECNC-Q8表现出最高的抗菌效率，导致PVA/ECNC-Q8纳米复合膜的抗菌活性最好。本研究为制备功能性、环境友好的PVA复合膜提供了一种有效的方法。所制备的PVA/ECNC-Qn纳米复合薄膜具有良好的力学性能和抗菌阻隔性能，在包装领域具有广阔的应用前景。
Cellulose nanocrystals (CNC) are natural, renewable, and biocompatible materials that have been widely used as new sustainable reinforcing nanofillers in polymer composites. We present polyvinyl alcohol (PVA)/CNC com-posites with improved mechanical and antibacterial properties using CNC-based nanofillers. The surface ester-ified CNC (ECNC) was prepared by 6-bromohexanoyl chloride via surface esterification. Subsequently, the alkyl bromide group of the ECNC was transferred to quaternary ammonium groups for preparing quaternized CNC (ECNC-Qn) by introducing tertiary amino groups with different carbon chain lengths (C8-C16). Then, ECNC-Qn were blended with a PVA matrix to prepare PVA/ECNC-Qn nanocomposite films via a solvent casting procedure. Diverse features, including light transmission, mechanical properties, and antibacterial activity against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria were investigated. Compared with pure PVA films, the PVA/ECNC-Qn nanocomposite films had higher tensile strength and higher antibacterial activity. Specifically, the maximum tensile strength and elongation at break of PVA/ECNC-Qn nanocomposite films were 45.4 MPa and 318.4%, respectively, which were 37.2% and 94.3% higher than those of pure PVA film, respectively. Moreover, the ECNC-Q8 exhibited the highest antibacterial efficiency, leading to the best anti-bacterial activity for PVA/ECNC-Q8 nanocomposite films among all films. This study demonstrates an efficient method for preparing a functional, environment-friendly PVA composite film. The prepared PVA/ECNC-Qn nanocomposite films exhibited considerable application potential in the packaging field, owing to their good mechanical and antibacterial barrier properties.