Wang Bin, Wang Xuezhou, Ma Hongxia, Li Jinpeng, Cao Daxian, Xu Jun, Zeng Jinsong, Gao Wenhua, Chen Kefu
Plant Fiber Material Science Research Center, State Key Laboratory of Advanced Papermaking and Paper-based Materials, School of Light Industry and Engineering, South China University of Technology, Guangzhou 510640, PR China.
Plant Fiber Material Science Research Center, State Key Laboratory of Advanced Papermaking and Paper-based Materials, School of Light Industry and Engineering, South China University of Technology, Guangzhou 510640, PR China.
Carbohydr Polym. 2025 Sep 15;364:123787. doi: 10.1016/j.carbpol.2025.123787. Epub 2025 May 22.
As an abundant, eco-friendly bio-material, starch has great potential to address pollution from petroleum-based plastic films, but starch-based films still need improved mechanical and barrier properties for practical use. Therefore, this study proposes an oxidation-dual crosslinking strategy. Native cassava starch (CS) was initially oxidized using NaIO4 to produce dialdehyde starch (DAS). Subsequently, polyvinyl alcohol (PVA) and cellulose nanofibrils (CNF) were incorporated into the DAS matrix, forming a compact-structured DAS composite film, through a dual crosslinking network involving acetalization reactions and intermolecular hydrogen bonding. Compared with the CS film, the optimized DAS-6c-12p composite film (with 6 % CNF and 12 % PVA based on the dry weight of DAS) demonstrated significant improvements in mechanical and barrier properties: tensile strength increased from 15.28 ± 1.11 MPa to 65.67 ± 2.50 MPa, tensile strain rose from 4.67 ± 0.68 % to 6.21 ± 0.13 %, water vapor permeability coefficient decreased from 11.50 ± 0.60 to 3.04 ± 0.19 g·mm/(m·d), oxygen permeability coefficient reduced from 10.322 ± 0.303 to 0.097 ± 0.003 cm·mm/(m·d·0.1 MPa), and edible oil permeability coefficient declined from 4.80 ± 0.14 to 0.50 ± 0.02 g·mm/(m·d). Notably, compared to the polyethylene packaging film, this composite film exhibited superior fruit preservation capability and biodegradability. This work provides a novel strategy for developing biobased high strength barrier film.
作为一种丰富的、环保的生物材料，淀粉在解决石油基塑料薄膜污染方面具有巨大潜力，但淀粉基薄膜在实际应用中仍需改善机械性能和阻隔性能。因此，本研究提出了一种氧化-双重交联策略。首先用高碘酸钠对天然木薯淀粉（CS）进行氧化，制备双醛淀粉（DAS）。随后，将聚乙烯醇（PVA）和纤维素纳米纤维（CNF）加入到DAS基质中，通过涉及缩醛化反应和分子间氢键的双重交联网络，形成结构致密的DAS复合薄膜。与CS薄膜相比，优化后的DAS-6c-12p复合薄膜（基于DAS干重含有6%的CNF和12%的PVA）在机械性能和阻隔性能方面有显著改善：拉伸强度从15.28±1.11MPa提高到65.67±2.50MPa，拉伸应变从4.67±0.68%提高到6.21±0.13%，水蒸气透过系数从11.50±0.60降至3.04±0.19g·mm/(m²·d)，氧气透过系数从10.322±0.303降至0.097±0.003cm·mm/(m²·d·0.1MPa)，食用油透过系数从4.80±0.14降至0.50±0.02g·mm/(m²·d)。值得注意的是，与聚乙烯包装薄膜相比，这种复合薄膜具有更好的水果保鲜能力和生物降解性。这项工作为开发生物基高强度阻隔薄膜提供了一种新策略。
