食品软包装用透明高阻隔涂料：PVA涂料研究进展

聚乙烯醇（PVA）因其良好的透明性和成膜性以及优异的氧气和有机溶剂阻隔性，可用于透明、易回收、环境友好型的食品高阻隔软包装材料。但因其涂层对湿度敏感性差且不具备水蒸气阻隔性能而制约其发展。针对这一问题，目前主要有两种解决方法：一种是PVA化学交联，PVA能进行多元醇的酯化、醚化、缩醛化等化学反应；另一种是制备PVA-纳米复合涂料，PVA与纳米层状材料如蒙脱土（MMT）以及氧化石墨烯（GO）复合涂料的研究已取得较大进展。为此，分别从PVA的阻隔性及其影响因素、化学交联PVA涂料以及PVA-纳米复合涂料的最新研究进展进行了综述，分析了改性PVA涂料面临的问题，展望其未来研究方向。

Research progress on the transparent and high barrier PVA coating for food flexible packaging

Poly(vinyl alcohol) (PVA) which are used for the transparent, recyclable, and environmental-friendly food high-barrier flexible packaging materials due to their good transparency and film-forming properties, as well as excellent oxygen and organic solvent barrier properties. However, the development of PVA coating is restricted by its poor humidity sensitivity and the lack of water vapor barrier properties. For these reasons, there are currently two main methods to solve the application problems of PVA coating: one method is to chemically cross-link PVA which can undergo the chemical reactions such as esterification, etherification and acetalization similar to other polyols containing secondary alcohols; the other method is to prepare PVA-nanomaterial composite coating, wherein the PVA and nano-layered materials such as montmorillonite (MMT) and graphene oxide (GO) have been made great progress. For this reason, the barrier properties of PVA and its influencing factors, chemically cross-linked PVA coatings and PVA-nanocomposite coatings were introduced, the problems faced by modified PVA coatings and prospects were analyzed, and their future research directions were prospected.