Order and Disorder in Strongly Segregated Block Copolymers

点击翻译按钮获取中文摘要

TECHNICAL SUMMARY:Block copolymers constitute one of the fastest growing segments of the polymer industry, which accounts for more than $300B annually of commerce in North America. These materials are prepared by coupling together two or more chemically distinct linear polymer chains, resulting in macromolecules endowed with multiple functionality and multifaceted physical properties that derive from segregation of the polymer blocks on a nanometer scale. Modern technical applications of block copolymers, for example in the microelectronics industry, require constantly diminishing and more complex nanoscale structures, below the limits set by current theoretical knowledge and practical understanding. This project aims to establish the fundamental principles that govern block copolymer phase behavior and mechanical properties in this new structural limit. Model materials, containing various combinations of two, three or more polymer blocks will be synthesized by controlled polymerization and characterized using small-angle x-ray and neutron scattering, electron microscopy, dynamic mechanical spectroscopy, and a host of other sophisticated techniques. These materials will be prepared near the order-disorder transition (ODT) by tightly controlling molecular weight and composition. The ODT represents a key processing parameter for designing multiblock copolymers for subsequent applications. The findings of this work are intended to spur new theoretical developments along with exciting practical applications. NON-TECHNICAL SUMMARY:Polymeric materials, including plastics and elastomers, medical devices and pharmaceutical aids, and key elements of the microelectronics industry constitute one of the most important commercial drivers in the nation's economy. This research program will guide the development of new and more versatile polymeric materials while educating the next generation of scientists and engineers working in this critical area of technology. New and more demanding applications of synthetic polymers mandates the development of microscopic structural features at nanometer length scales, thousands of times smaller than the diameter of a human hair. The scientific and engineering goals will be achieved through state of the art synthetic chemistry coupled with sophisticated structural analysis and physical property evaluation. This technical program will provide industry with competitive tools for the design and implementation of new and innovative products. Interest in science and engineering will be fostered in students in grades 3-12 through an interactive program called Energy and U. This activity brings thousands of students and numerous families to the University annually for an experience that stimulates awe and excitement while teaching important lessons about energy and society.