Nguyen Hoang-Linh, Hanif Zahid, Park Seul-A, Choi Bong Gill, Tran Thang Hong, Hwang Dong Soo, Park Jeyoung, Hwang Sung Yeon, Oh Dongyeop X
Research Center for Bio-based chemistry, Korea Research Institute of Chemical Technology (KRICT), Ulsan 44429, Korea.
Division of Environmental Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea.
Polymers (Basel). 2018 May 5;10(5):501. doi: 10.3390/polym10050501.
This paper introduces a boron nitride nanosheet (BNNS)-reinforced cellulose nanofiber (CNF) film as a sustainable oxygen barrier film that can potentially be applied in food packaging. Most commodity plastics are oxygen-permeable. CNF exhibits an ideal oxygen transmission rate (OTR) of <1 cc/m²/day in highly controlled conditions. A CNF film typically fabricated by the air drying of a CNF aqueous solution reveals an OTR of 19.08 cc/m²/day. The addition of 0⁻5 wt % BNNS to the CNF dispersion before drying results in a composite film with highly improved OTR of 4.7 cc/m²/day, which is sufficient for meat and cheese packaging. BNNS as a 2D nanomaterial increases the pathway of oxygen gas and reduces the chances of pinhole formation during film fabrication involving water drying. In addition, BNNS improves the mechanical properties of the CNF films (Young's modulus and tensile strength) without significant elongation reductions, probably due to the good miscibility of CNF and BNNS in the aqueous solution. Addition of BNNS also produces negligible color change, which is important for film aesthetics. An in vitro cell experiment was performed to reveal the low cytotoxicity of the CNF/BNNS composite. This composite film has great potential as a sustainable high-performance food-packaging material.
本文介绍了一种氮化硼纳米片（BNNS）增强的纤维素纳米纤维（CNF）薄膜，作为一种可持续的氧气阻隔薄膜，有望应用于食品包装。大多数商用塑料都是透气的。在高度可控的条件下，CNF的理想氧气透过率（OTR）<1 cc/m²/天。通过空气干燥CNF水溶液通常制备的CNF薄膜的OTR为19.08 cc/m²/天。在干燥前向CNF分散体中添加0⁻5 wt%的BNNS，可得到复合薄膜，其OTR显著提高至4.7 cc/m²/天，这对于肉类和奶酪包装来说已经足够。作为二维纳米材料的BNNS增加了氧气的传输路径，并减少了在涉及水干燥的薄膜制造过程中形成针孔的机会。此外，BNNS改善了CNF薄膜的机械性能（杨氏模量和拉伸强度），而不会显著降低伸长率，这可能是由于CNF和BNNS在水溶液中具有良好的混溶性。添加BNNS还产生了可忽略不计的颜色变化，这对于薄膜的美观很重要。进行了体外细胞实验以揭示CNF/BNNS复合材料的低细胞毒性。这种复合薄膜作为一种可持续的高性能食品包装材料具有巨大潜力。
