Ultrastructural Properties of Polymers

本文研究了嵌段共聚物和嵌段共聚/均聚物共混体系的微观结构。不同结构、组成和相对分子质量的链条将自组装成整齐的二嵌段和二嵌段/均聚物(S)结构。重点将放在新的工艺上，以便提供各种所需几何形状的大单晶样件。在有序-有序相变和沿特定高对称方向的机械变形过程中，微区形态的演变将被定量跟踪，以获得关于嵌段共聚体系相变的基本原理及其大应变力学行为的信息。主要研究技术有铸轧、力学测试、光学显微镜、小角X射线散射、透射电子显微镜、扫描电子显微镜、数字图像分析和表面计算机图形学。本研究的目的是促进对加工-结构-性能关系的基本理解，从而为开发性能更好的聚合物材料提供基础。

This study deals with the microstructures of block copolymer and block copolymer/homopolymer blend systems. Self-assembled neat diblock and diblock/homopolymer(s) structures will be formed from chains of various architecture, composition and molecular weight. Emphasis will be placed on novel processing so as to provide large single-crystal-like samples of various desired geometries. The evolution of the microdomain morphology during order-order phase transitions and during mechanical deformation along particular high symmetry directions will be quantitatively followed to obtain information on the fundamentals of phase transitions in block copolymer systems and on their large strain mechanical behavior. The main investigative techniques are roll casting, mechanical testing, optical microscopy, small-angle x-ray scattering, transmission electron microscopy, scanning electron microscopy, digital image analysis, and computer graphics of surfaces. The goal of the research is to contribute to the basic understanding of processing-structure-property relationships, which can provide a basis for development of polymeric materials with improved performance.