Phosphorous-Containing Epoxy Resins for Room Temperature VARTM

The Navy intends to start using a significant quantity of composite structures in surface ship construction in an effort to decrease costs as well as to reduce the visibility of the ships to radar. The large size of the target structures necessitates the use of low temperature, non-autoclave processing techniques such as Vacuum Assisted Resin Transfer Molding (VARTM). In the recent past, most marine composites were based on glass fibers, but due to the mechanical property requirements of the newer applications, carbon fibers will be required as reinforcements for future structures. Currently, the matrix material of choice is a vinyl ester resin based on its superior mechanical properties. Vinyl ester resins work well with glass fiber reinforcements, but do not adhere well to carbon fibers, leading to lower overall composite performance due to the poor fiber-matrix interface. This Phase I program proposes the development of a phosphorus-containing epoxy resin that would not only improve the quality of the fiber-matrix interface in VARTM-processed composites for shipboard applications while meeting the Tg requirements, but would also offer enhanced fire retardance relative to current resin systems. BENEFITS: The phosphorus-containing epoxy resins for room temperature VARTM processing will find immediate application in military applications both in Naval vessels as well as in aircraft. Transitions to the civilian marine and aircraft industries are expected.