A Molecular Dynamics Study on Polycaprolactone -Metal Oxide Interactions

Abstract In order to realize the macroscopic features of a number of chemically bonded multi-layer dielectric and composite materials, interactions of metal oxide surfaces, polymer surface atoms, and near-surface atoms are very beneficial. The simulation study of polymer-metal oxides interfaces is of great importance in investigating the adhesion and miscibility features of these systems that are inherently challenging to obtain experimentally or for which there is no experimental data, even if some low data exist, they are not reliable. Polycaprolactone (PCL) is biocompatible, biodegradable, non-toxic and hydrophobic polyester that has been used in tissue engineering, such as a bioactive implant. Hence, the molecular dynamics simulations of PCL are carried out to investigate its surface interaction with metal oxides as ZnO, CuO, Fe2O3, NiO and SiO2. The force field of COMPASS is applied to simulations in order to compute interfacial and solubility parameters. Molecular dynamics approach to investigate the interaction and adsorption manner of PCL with metal oxides. Whereas investigations are useful in exploring polymer composites. Much better adhesion is achieved by the calculations between the PCL oligomer and the metal oxides under investigation. The negative values of interaction energy have to be forecasted despite the presence of acid-base or hydrogen-bonding interactions.摘要：为阐明多种化学键合多层介电材料与复合材料的宏观特性，金属氧化物表面、聚合物表面原子及近表面原子间的相互作用具有关键研究价值。针对聚合物-金属氧化物界面开展模拟研究，对探究这类体系的界面粘附与混溶特性至关重要——此类体系的实验数据往往难以获取，即便存在少量数据，其可靠性也欠佳。聚己内酯（Polycaprolactone, PCL）是一种生物相容性优良、可生物降解、无毒且疏水的聚酯材料，已被应用于组织工程领域，例如用作生物活性植入物。为此，本研究通过分子动力学模拟，探究聚己内酯与氧化锌（ZnO）、氧化铜（CuO）、三氧化二铁（Fe₂O₃）、氧化镍（NiO）及二氧化硅（SiO₂）等金属氧化物的表面相互作用。模拟过程采用COMPASS力场，用于计算界面参数与溶解度参数。本研究采用分子动力学方法，解析聚己内酯与金属氧化物的相互作用与吸附模式，相关研究可为聚合物复合材料的开发提供理论依据。计算结果显示，聚己内酯低聚物与本次研究涉及的金属氧化物之间可实现更优异的界面粘附性能。即便体系中存在酸碱相互作用或氢键相互作用，相互作用能仍可被预测为负值。