Research Initiation Award: Theoretical and Experimental Studies of the Surface Segregation of Polymer Chains Due to Specific Energetic Interactions

二元聚合物共混物中单一物种的表面偏析对决定聚合物-基材复合材料的强度有重要影响。在这方面，建议研究二元共混物的表面行为，其中一条链的所有链段与表面相同地相互作用，而与第一链具有相同重复单元的第二物种的末端部分，与表面有不同于中心珠子的能量相互作用。关于这个问题的初步分析计算表明，第二种物种的链端和中间珠与表面之间的能量相互作用的不同将决定哪种成分将对其进行分区。由此可以通过控制末端部分的化学来最大化来自共混物的适当物种的表面分离，从而允许设计具有所需机械性能的聚合物复合材料。在实验上，这些理论预测将被一种名为中子反射率的新技术所验证。从理论的角度来看，正在开发分析晶格模型来研究这些情况。

The surface segregation of one species from a binary polymer blend has important consequences in determining the strength of polymer- substrate composites. In this it is proposed to study the surface behavior of a binary blend, in which all segments of one chain interact identically with the surface, while the end moieties of the second species, which has the same repeat units as the first chain, have energetic interactions with the surface that are different from the central beads. Preliminary analytical calculations on this subject suggest that the difference in energetic interactions between chain ends and middle beads of the second species with the surface will dictate which component will partition to it. It follows that one can maximize the surface segregation of an appropriate species from the blend by controlling the chemistry of the end moieties, thus allowing for the design of polymer composite with desired mechanical properties. Experimentally, these theoretical predictions will be verified by a new technique, neutron reflectivity. From a theoretical viewpoint, analytical lattice models are being developed to examine these situations.