Polymer dynamics in the polymer-solid interphase: molecular dynamics simulations of 1,4- polybutadiene at graphite and alumina surfaces

我们将使用分子动力学模拟研究1，4-聚丁二烯劳斯链的化学现实模型。化学现实的方法允许定量确定各种实验上可获得的弛豫函数（例如，介电响应、NMR、散射）。我们的模拟产生这些实验观测值，但除此之外，可以解决作为一个函数的距离固体界面上的一个更精细的规模比实验可能的，提供了详细的机械图片的分段和大尺度运动的实验数据。我们将扩展我们的研究1，4-聚丁二烯对石墨的玻璃化转变温度，以确定在何种程度上的长度范围内的固体支持影响熔体动力学的增加。我们将扩大这项工作，也看在无定形支持，选择氧化铝作为模型表面上的这种聚合物的弛豫行为。为了研究固体约束对适度纠缠链的动力学的影响，我们将采用我们最近开发的1，4-聚丁二烯的粗粒度模型，并将其扩展到与壁的相互作用。此外，我们将研究的结构和动力学的聚合物刷接枝到纳米粒子的理论和模拟方法。

We will study a chemically realistic model of 1,4-polybutadiene Rouse chains using Molecular Dynamics simulations. The chemically realistic approach allows for a quantitative determination of a variety of experimentally accessible relaxation functions (e.g., dielectric response, NMR, scattering). Our simulations yield these experimental observables but in addition can be resolved as a function of distance to the solid interface on a much finer scale than experimentally possible, providing a detailed mechanistic picture of the segmental and large scale motions underlying experimental data. We will extend our study of 1,4-polybutadiene on graphite towards the glass transition temperature to determine to which degree the length scale over which the solid support influences the melt dynamics increases. We will expand this work by also looking at the relaxation behavior of this polymer on an amorphous support, choosing alumina as the model surface. To study the influence of solid confinement onto the dynamics of moderately entangled chains we will employ a coarse-grained model of 1,4-polybutadiene, which we have developed recently, and extend it to incorporate interactions with walls . Furthermore, we will study the structure and dynamics of polymer brushes grafted onto nanoparticles by theoretical and simulation methods.