Segment Density and Coil Dimensions of Polymer Chains Anchored to Solid Surfaces

聚合物与固体表面直接接触形成界面，其中链段具有不同于体中的形状和密度剖面。这些界面诱导效应，其程度和位置取决于诸如数量、结构、刚度和靠近固体表面的链的摩尔质量等参数。目的是通过对表面锚定聚合物链的节段构象的位点解析分析，深入了解这种界面相及其对材料性能的影响：合成了具有不同摩尔质量、结构和结构（线性、支化、无定形、半晶）的定义良好的聚合物，这些聚合物仅在特定的链段中氘化（“H/D嵌段共聚物”）。这些链将固定在平面和弯曲的固体基板上，从而覆盖接枝密度的全部可达范围。所得聚合物层在(i)与空气接触、（ii）彼此直接接触、（iii）与自由聚合物链或（iv）与溶剂接触、(v)在应变和变形下使用中子和x射线小角散射和x射线反射法进行分析。获得的见解可以用作模拟工作，核磁共振和原子力显微镜研究的输入，并将大大加深对聚合物（纳米）复合材料性质的理解。

Polymers being in direct contact with solid surfaces form interphases in which the chain segments assume shapes and segment density profiles different from those in the bulk. These interface-induced effects, their extent and location depend on parameters such as number, architecture, rigidity, and molar mass of the chains next to the solid surface. It is the aim to develop profound knowledge about this interphase, and of its consequences for the material properties, via site-resolved analysis of the segment conformation of surface-anchored polymer chains: well-defined polymers of different molar mass, constitution and architecture (linear, branched, amorphous, semi-crystalline) are synthesized, which are deuterated in specific chain segments only (“H/D block copolymers”). These chains will be immobilized on planar and bent solid substrates, thereby covering the full accessible range of grafting densities. The resulting polymer layers are analyzed when (i) in contact with air, (ii) in direct contact with each other, (iii) in contact with free polymer chains or (iv) with solvents, and (v) under strain and deformation, using neutron and X-ray small angle scattering and X-ray reflectomery. The gained insights can be used as input for simulation work, NMR and AFM studies, and will deepen understanding of the properties of polymer (nano)composites considerably.