Precursor Structure-Fiber Property Relationships in Polyacrylonitrile- Based Carbon Fibers

Carbon fibers occupy a premier position among high performance fiber structures, with a combination of physical and mechanical properties, in tension and in compression, that makes them uniquely suitable for application in many advanced fiber-reinforced composites. Fundamental investigations pertaining to precursor fibers and conversion processes in the last decade have paved the way for significant improvements in mechanical properties, especially in the tensile properties of polyacrylonitrile- PAN based fibers. Much of the empiricism which existed in the early phases of carbon fiber development has been replaced by fundamental knowledge of the evolution of structure and properties. Georgia Tech has been a significant contributor to this global effort, with important contributions and current research spanning the range from acrylic precursor fiber formation, through oxidative stabilization, to carbonization. The primary objectives of the research reported here have been to strengthen the fundamental knowledge base and to provide rational directions for advances in precursor fiber structures and process routes to generate new morphologies and superior mechanical properties in PAN-based carbon fibers. Significant progress in this direction has been made through a general emphasis on exploration of the fundamental aspects of the chemical and morphological evolution from PAN-based precursors to carbon fibers.