This work investigates the interfacial adhesion of PA6/PP‐g‐MA in a thin‐walled multilayer part obtained by injection overmoulding. This process is a good solution to the need of weight reduction for the sustainable and economic growth of food packaging. A rigid plastic food package is a complex multilayer structure obtained from the association of polymers with different properties to achieve good barrier, environment, or thermo‐mechanical performance. The present study aims to obtain a complete understanding of the interfacial adhesion of PA6/PP‐g‐MA interface in a three‐layer PA6/sealant/PP assembly through microscopy analysis, mechanical characterization, and inter‐diffusion models. Optical microscopy, XPS, and AFM analyses showed the presence of a copolymer interphase. This layer is greatly dependent on the holding pressure applied, which revealed to be the key parameter to obtain the best results in terms of failure strength. A better interface wettability improves the inter‐diffusion distance and thus chemical grafting efficiency. Other interface improvements were achieved by the addition of EVA in the PP‐g‐MA layer. The lowest viscosity of the EVA dispersed phase has led to a fully cohesive failure due to an interface diffusion efficiency. The presence of EVA increased more than 80% of the peeling performance of the assemblies.

中文翻译：

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聚酰胺6 /聚丙烯多层部件的薄壁注模成型：PA6 / PP-g-ma界面粘合研究

这项工作研究了通过注塑包覆成型获得的薄壁多层零件中PA6 / PP-g-MA的界面粘附性。这个过程是减轻重量以实现食品包装的可持续和经济增长的良好解决方案。硬质塑料食品包装是一种复杂的多层结构，是通过将具有不同特性的聚合物结合而获得的，以实现良好的阻隔性，环境或热机械性能。本研究旨在通过显微镜分析，机械表征和相互扩散模型，全面了解三层PA6 /密封胶/ PP组件中PA6 / PP-g-MA界面的界面粘附性。光学显微镜，XPS和AFM分析表明存在共聚物中间相。该层很大程度上取决于施加的保压，根据失效强度，这是获得最佳结果的关键参数。更好的界面润湿性可改善相互扩散距离，从而提高化学接枝效率。通过在PP-g-MA层中添加EVA，可以实现其他界面改进。EVA分散相的最低粘度由于界面扩散效率而导致完全的内聚破坏。EVA的存在提高了组件剥离性能的80％以上。EVA分散相的最低粘度由于界面扩散效率而导致完全的内聚破坏。EVA的存在提高了组件剥离性能的80％以上。EVA分散相的最低粘度由于界面扩散效率而导致完全的内聚破坏。EVA的存在提高了组件剥离性能的80％以上。