Computer Simulation of Structure Prediction for Polymer Blend and Alloy

基于以往的研究综述，包括我们的研究，我们认为动力学模拟对于预测纤维填充和颗粒填充聚合物复合材料的结构发展是有效的，聚合物共混物和聚合物合金，我们可以系统地处理这些预测作为一种模拟技术。首先，我们开发了预测技术的三个-通过动态颗粒模拟，研究了复合材料中纤维的尺寸行为。预测了单根纤维在简单剪切和拉伸流场中的取向、变形和断裂，得到了物理上合理的结果，并与一些实验结果相吻合。此外，我们扩展了这种技术的纤维集中的材料，通过添加纤维-纤维的相互作用。该模拟方法只进行粒子跟踪，简化了计算过程，易于预测聚合物共混物的分布。它可以应用于 ...更多信息 艾德通过引入内聚力对颗粒在颗粒填充材料中的分散性进行预测，如果能够成功地建立液滴破碎模型，则对聚合物合金的结构预测有一定的指导意义。改变链段数和链数的模拟结果表明，该模型能较好地反映真实的高分子链的松弛行为。然而，当假设一个链段中存在几十个单体时，该模型不能适当地代表排除的体积效应。新的模型必须讨论，因为在一个链段中需要数百个单体，以便分子动力学的结果与连续体物理性质相关。本文提出了一种新的模型--“管模型”，它既能有效地显示扩展体积效应，又具有弹簧-珠模型的优点，最后提出了几种本构方程的材料常数的优化计算方法，并讨论了材料模型的适用性。研究发现，对于弱缠结的聚合物体系，有几种模型可以预测剪切场和拉伸场中的材料行为，但对于复杂体系，每个弛豫模式下的非线性材料常数需要多个值，且需要大量的弛豫模式。少

We considered based upon the previous research survey including our study that the dynamics simulation is effective for the prediction of structure development of fiber-filled and particle-filled polymer composite materials, polymer blends and polymer alloys and we can systematically deal with these predictions as a simulation technique.First we developed the prediction technique of three-dimensional behavior of fibers in a composite material by means of the dynamic particle simulation. We predicted the orientation, deformation and break of a single fiber in simple shear and elongation flow fields and the obtained results were found to be physically reasonable and be in agreement with some experimental results. Also we extended this technique to fiber-concentrated material by adding the fiber-fiber interaction. This simulation technique can be simplified and become easier for the distribution prediction of polymer blend because that only the particle trace is performed. It can be appli … More ed to the prediction of particle dispersion in particle-filled materials by adding the cohesive power, and to structure prediction in polymer alloys if we can make the successful model for the break up of liquid drop.Next we developed the prediction technique of polymer configuration using the spring-bead model by means of the molecular dynamics simulation and discussed the equivalence of the molecular model to the actual polymer. The simulation results varying the numbers of segments and chains showed that this model can represent the relaxation behavior of real polymer chain. However this model cannot appropriately represent the excluded volume effect when existence of several scores of monomers are assumed in a segment. The new model have to be discussed as several hundreds of monomers in a segment are required in order that the results by molecular dynamics are related to the continuum physical properties. We proposed the new model, "tube model", which can successfully show the extended volume effective and still have the merit of the spring-bead model.Last we developed the calculation method of optimized determination of material constants from experimental data of rheological properties for several constitutive equations and discussed the applicability of material models. It was found that several models can predict the material behavior in shear and elongation fields for weak-entangled polymer systems but multi values of non linear material constants in each relaxation mode and large number of relaxation modes were required for complicated systems. Less