标题： 聚乙烯、水和潜在抗静电及滑爽添加剂之间的分子间相互作用：分子动力学研究 显示英文标题

标题： Intermolecular Interactions between Polyethylene, Water, and Potential Antistatic and Slip Additives: a Molecular Dynamics Study

摘要： 添加剂对于增强或调整塑料的性能以满足特定应用至关重要。 然而，找到合适的添加剂可能具有挑战性，因为我们缺乏它们与塑料以及与水分之间的相互作用及其相互作用的知识。 在本研究中，我们通过原子级分子动力学模拟研究了一种商业添加剂以及两种新的潜在添加剂在聚乙烯中的抗静电和滑动性能。 我们揭示了聚乙烯、这些分子中的每一个与水之间的最有利相互作用，并提供了它们界面结构的微观图像。 所有添加剂主要通过其极性头部与水相互作用，水根据添加剂的不同而作为氢键受体或供体。 如预期的那样，水不会进入聚乙烯基质；它会积聚在其表面，且没有优先取向。 所研究的添加剂在与聚合物混合时表现出显著不同的结构：其中两种以不同程度进入聚合物基质，要么通过将其链与聚乙烯链插入，要么通过形成类似胶束的结构，而第三种则保留在表面。 当水被引入系统时，一些添加剂/聚乙烯系统的结构会发生变化。 这些变化的程度和性质取决于所有组分的相对浓度。 如果添加剂浓度较低，水会以液滴状保留在材料表面。 添加剂是否渗透并组织聚合物取决于是否有水存在。 我们预测我们提出的两种分子中的一种具有有前途的抗静电性能，而另一种可以作为滑动剂使用。 我们希望我们的预测能激发在实验室中测试这些分子作为聚乙烯添加剂的兴趣。 显示英文摘要

摘要： Additives are essential to enhance or modify the properties of plastics for target applications. However, finding appropriate additives may be challenging, since we lack knowledge on their interactions with the plastics and with moisture, and the interplay between them. In this work, we study a commercial additive as well as two new potential additives for their antistatic and slip properties in polyethylene by means of atomistic molecular dynamics simulations. We reveal the most favorable interactions between polyethylene, each of these molecules and water, along with providing a microscopic picture of their interfacial structure. All additives interact with water mainly by their polar heads, with water acting as a hydrogen bond acceptor or donor depending on the additive. As expected, water does not enter the polyethylene matrix; it accumulates at its surface instead, without any preferencial orientation. The additives studied exhibit remarkably different structures when they are mixed with the polymer: two of them enter the polymer matrix to various degrees, either by intercalating their chains with the polyethylene ones or by forming miscellar-like structures, while the third one stays at the surface. When water is incorporated into the system, the structure of some of the additive/polyethylene systems changes. The magnitude and nature of these changes depend on the relative concentrations of all species. If the additives are in low concentrations, water stays at the surface of the material, in a drop-like shape. The additives penetrate and organize the polymer more or less depending on whether water is present or not. We predict that one of our two proposed molecules has promising antistatic properties while the other one could be applied as a slip agent. We hope that our predictions will spark interest in testing these molecules in the laboratory as polyethylene additives.