Abstract Since hydrophobicity can improve the usability and functionality of materials in humid condition, enhancing the hydrophobic behavior of starch films or papers is of importance. In this work, ZnO nanoparticles (NPs) were introduced into the starch solution under ultrasonic and magnetic-stirring, followed by cast filming and paper coating. The contact angles of resulting film and coated paper containing 2% (wt) NPs were increased from 85.73° to 121.45°, 64.47° to 103.94°, respectively. The results from comprehensive characterizations confirmed the hierarchical structure created by ZnO nanoparticles on the surface of starch film as well as the formation of intact layers on coated paper. The excellent miscibility between starch and ZnO NPs was also achieved. The approach developed is promising and facilitates the hydrophobic modification of green-based materials.

中文翻译：

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ZnO纳米颗粒增强淀粉薄膜和纸张的疏水性

摘要 由于疏水性可以提高材料在潮湿条件下的可用性和功能性，因此增强淀粉薄膜或纸的疏水性具有重要意义。在这项工作中，在超声波和磁力搅拌下将 ZnO 纳米颗粒 (NPs) 引入淀粉溶液中，然后进行流延成膜和纸张涂层。所得薄膜和含有 2% (wt) NPs 的涂层纸的接触角分别从 85.73° 增加到 121.45°、64.47° 到 103.94°。综合表征的结果证实了 ZnO 纳米粒子在淀粉膜表面形成的分层结构以及在涂布纸上形成完整层。还实现了淀粉和 ZnO NPs 之间极好的混溶性。