Regulating the Interface in Graphite/Thermoplastic Composites

Among the many engineering thermoplastics available today, there exists a large subgroup of difficult-to-crystallize or amorphous polymers which possess a rather unique micronodular morphology in their normally produced solid state. When these polymers are processed in the unfilled state, changes in process thermal history have little effect on mechanical properties; but when reinforcement such as graphite is added, pronounced effects of thermal treatment arise which are relatable to the nodular polymer morphology. These effects will be documented and explained for graphite fiber-filled polycarbonate and poly(phenylene oxide). The practical application of these results to hot-forming techniques will also be described. Finally, extension of these techniques to the more easily crystallized thermoplastics such as polypropylene will be considered.