Peek Composites: Processing-Morphology-Property Relationships.

Thermoplastic composites represent one of the most prominent emerging technologies in the advanced composite field. Taking PEEK (polyetheretherketone) as a prime example of this new generation of engineering material, the advantages afforded by its utilization over the more conventional thermosetting epoxy materials include order-of-magnitude improvements in fracture toughness, delamination, water and solvent resistance. The processing flexibility associated with thermoplastic systems can, in addition, significantly reduce processing costs. However, as PEEK becomes increasingly utilized in the critical structures for which it was developed, some important fundamental questions are just beginning to be addressed. These questions deal with understanding how processing conditions affect morphology, and, in turn, how morphological variables such as crystallinity and spherulite size affect the mechanical properties of the material. The state of the art in the development of such processing- morphology-property relationships in PEEK composites is reviewed. This review is being written as a chapter in ``The Encyclopedia of Composites'' by VCH Publishers.