Modelling Flow and Crystalisation in Polymers Developing Molecular Models and Simulations: Polymer Dynamics and Phase Transitions

在本论文中，我们的目标是通过使用一系列分析、数值和随机技术开发聚合物动力学和相变的分子模型和模拟，进一步发展对聚合物结晶的理解。聚合物动力学中出现了复杂性，因为聚合物是由长链分子组成的，利用捕获这些链之间相互作用的模型可以获得聚合物流变学领域独有的特性。许多聚合物流体在冷却时会结晶，这是它们与简单流体共有的一个特征，但结晶过程本身是显著不同的，因为它受到组成链连接方式的影响，导致了许多无法解释的现象。此外，如果聚合物流体处于流动状态，那么聚合物结晶的难易程度和所得晶体内聚合物链的排列都可能有很大的不同。这种成核机制还没有被很好地理解，因此聚合物结晶领域将受益于包含聚合物不寻常行为的模型的创建。

In this thesis we aim to further develop the understanding of polymer crystallisation by developing molecular models and simulations for polymer dynamics and phase transitions using a range of analytical, numerical and stochastic techniques. Complexities arise in polymers dynamics since polymers are composed of long chain molecules, and utilising models that capture interactions between these chains leads to properties that are unique to the field of polymer rheology. Many polymer fluids crystallise when cooled, a feature that they share with simple fluids, but the crystallisation process itself is significantly different as it affected by the way the constituent chains are connected, leading to a multitude of unexplained phenomena. Furthermore, if a polymer fluid is placed under flow, both the ease with which the polymer crystallises and the arrangement of the polymer chains within the resulting crystal can differ greatly. This nucleation mechanism is not very well understood, and thus the area of polymer crystallisation would benefit from the creation of models that incorporate the unusual behaviour of polymers.