Characteristics sought include high thermal stability, low water absorption, and processability.

Improved, readily processable thermosetting polymer resins are being developed for use as matrix materials in composite-material structures in applications in which there are requirements for thermal stability and hot-wet performance. Heretofore, the development and utilization of polymer resins for such applications have been limited by adverse characteristics that include (1) toxicity of many of the chemicals used to make the resins; (2) poor performance during fires (excessive flame and smoke, dripping, and generation of hazardous substances); (3) significant absorption of water in humid environments, linked to delamination during rapid heating; and (4) in the cases of many of the polymers suitable for use at the highest temperatures, difficulties in the use of newer, less expensive fabrication techniques.

These Molecular Structures are those of resins of high-thermal-stability, low-water-absorption polymers for composite materials for high-temperature applications.