Lee Jae Sik, Lee Nam-Heui, Peri Somesh, Foster Mark D, Majkrzak Charles F, Hu Renfeng, Wu David T
Department of Polymer Science, The University of Akron, Akron, Ohio 44325, USA.
National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Phys Rev Lett. 2014 Nov 28;113(22):225702. doi: 10.1103/PhysRevLett.113.225702. Epub 2014 Nov 26.
The contributions of chain ends and branch points to surface segregation of long-branched chains in blends with linear chains have been studied using neutron reflectometry and surface-enhanced Raman spectroscopy for a series of novel, well-defined polystyrenes. A linear response theory accounting for the number and type of branch points and chain ends is consistent with surface excesses and composition profile decay lengths, and allows the first determination of branch point potentials. Surface excess is determined primarily by chain ends with branch points playing a secondary role.
利用中子反射仪和表面增强拉曼光谱，对一系列新型的、结构明确的聚苯乙烯进行了研究，以探讨支链末端和支化点对长支链与线性链共混物表面偏析的贡献。一种考虑支化点和链端数量及类型的线性响应理论，与表面过量和组成分布衰减长度一致，并首次确定了支化点势。表面过量主要由链端决定，支化点起次要作用。
