The Impact of a Solid Surface on the Structure and Dynamics of Polymer Melts

固体表面对聚合物熔体结构和动力学的影响

• 批准号: 68175862
• 负责人: Professor Dr. Wolfgang Knoll
• 金额: --
• 依托单位: Austrian Institute of Technology (AIT)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/68175862?language=en
• 关键词: Impact; Solid; Surface; Structure; Dynamics

We propose a combined experimental and theoretical investigation of the effect of a solid (metal) surface on the structure, conformation and dynamics of polymer melts in contact to this substrate. Poly(isoprene) (PI), poly(butadiene) (PB), and poly(ethylene) (PE) will be studied in contact with various metal surfaces (gold, silver and platinum) used as solid supports. These substrates will allow us to investigate the effect of the different surfaces on the polymer structural properties. We will additionally modify metal surfaces (e.g. thiol SAMs) to systematically change the polymer/substrate interaction from essentially attractive via neutral to repulsive in order to investigate bulk properties in contact to surfaces. The basic experimental approach for probing the inter-phase between the polymer and the solid is based on surface plasmon optics (PSP) with an emphasis on long-range (LRSP) and short-range surface plasmon modes (SRSP). The evanescent character of these surface-electromagnetic waves provides exquisite interfacial sensitivity and selectivity, with no interference from bulk contributions to the detected signal. By varying the wavelength of the employed laser light source or by using Au layers of different thicknesses, we can continuously tune the depth of the evanescent (i.e., exponentially decaying) optical field extending from the substrate surface into the polymer sample from about 10nm (1/e decay length) to beyond 1micron. Thus, we can probe the full range of the solid/polymer system with 2 different regimes, i.e., a polymer/solid interface and a “semi-infinite” polymeric interphase extending normal to the interface into the bulk polymer. For the theoretical studies multi-scale methods that combine atomistic and coarse-grained (CG) simulations will be used. The combined hierarchical use of atomistic and CG simulations in the polymer/solid systems will allow us to calculate the correct time scales in the CG simulations and to quantitatively study the effect of the surface on the structure and the dynamics of long entangled polymer melts.

我们提出了一个相结合的实验和理论研究的固体（金属）表面上的结构，构象和动力学的聚合物熔体接触到这个基板上的效果。将研究与用作固体载体的各种金属表面（金、银和铂）接触的聚（异戊二烯）（PI）、聚（丁二烯）（PB）和聚（乙烯）（PE）。这些基板将使我们能够研究不同表面对聚合物结构特性的影响。我们将另外修改金属表面（例如硫醇自组装膜），以系统地改变聚合物/基底相互作用，从基本上吸引通过中性到排斥，以研究接触表面的整体性质。用于探测聚合物和固体之间的界面相的基本实验方法是基于表面等离子体光学（PSP），重点是长程（LRSP）和短程表面等离子体模式（SRSP）。这些表面电磁波的倏逝特性提供了精致的界面灵敏度和选择性，没有来自对检测信号的大量贡献的干扰。通过改变所采用的激光光源的波长或通过使用不同厚度的Au层，我们可以连续地调谐倏逝波的深度（即，指数衰减的）光场从基底表面延伸到聚合物样品中，从约10 nm（1/e衰减长度）到超过1微米。因此，我们可以用2种不同的方式探测固体/聚合物体系的全部范围，即，聚合物/固体界面和垂直于界面延伸到本体聚合物中的“半无限”聚合物界面。对于理论研究的多尺度方法，联合收割机结合原子和粗粒度（CG）的模拟将被使用。在聚合物/固体系统中的原子和CG模拟相结合的层次使用将使我们能够计算正确的时间尺度的CG模拟和定量研究的表面上的结构和长纠缠聚合物熔体的动力学的影响。