A molecular dynamics approach to modelling oxygen diffusion in PLA and PLA clay nanocomposites
A molecular dynamics approach to modelling oxygen diffusion in PLA and PLA clay nanocomposites
复制标题
DOI：
10.1039/d3ma00158j
复制
发表时间：
2023-04-24
影响因子：
5
通讯作者：
Parker，S. C.
中科院分区：
文献类型：
--
作者：
Lightfoot，J. C.;Castro-Dominguez，B.;Parker，S. C.
聚乳酸（PLA）是一种新兴的生物塑料，被认为是包装应用中石油衍生的一次性塑料的可持续替代品。这具有全球意义，因为该行业占塑料消费量的38%，只有三分之一的废物被回收利用。提高可生物降解的PLA的阻隔性能的一种方法是通过添加粘土填料，目前通过试错实验对其进行了探索。由于组分之间复杂的界面相互作用，数学模型无法在合成之前可靠地预测潜在的改进。我们概述了原子级分子动力学和蒙特卡罗模拟技术，以产生聚合物纳米粘土复合材料系统，并实现高度准确的预测气体扩散。我们强调的统计要求，这是历史上没有满足聚合物/气体扩散建模，并提供了第一次调查渗透剂扩散和自由体积之间的关系在PLA复合材料。这些预测技术的广泛使用可以指导实验研究，开发上级可持续包装材料。
Poly(lactic acid), PLA, is an emerging bioplastic, considered a sustainable alternative to petroleum-derived, single-use plastics for packaging applications. This is of global significance, as this industry accounts for 38% of plastic consumption, with only one third of waste recycled. One approach to enhance the barrier performance of biodegradable PLA is via the addition of clay fillers, which are currently explored through trial-and-error experiments. Mathematical models fail to reliably predict potential improvements prior to synthesis, due to complex interfacial interactions between components. We outline atom-level molecular dynamics and Monte Carlo simulation techniques to generate polymer nanoclay composite systems and achieve highly accurate predictions of gas diffusion. We highlight statistical requirements which are historically not met in polymer/gas diffusion modelling and provide the first investigation into the relationship between penetrant diffusion and free volume in PLA composites. Widespread use of these predictive techniques can direct experimental research, towards developing superior sustainable packaging materials.