Co-Injection Resin Transfer Molding (CIRTM)

Shipboard structures employing composites typically use glass/vinyl ester (VE) manufactured with vacuum assisted RTM. This composite system offers reduced weight, no corrosion and improved signature performance but lacks the fire performance characteristics required for shipboard use. Phenolic resins (PH) provide outstanding fire performance but are difficult to process and offer lower structural properties. No existing single resin system can meet all of the requirements in a given application for Naval shipboard structures. The co-injection resin transfer molding (CIRTM) process was developed by the University of Delaware and the Army Research Laboratory to simultaneously inject two (or more) resins into a dry composite preform maintaining discrete layers of resin through the thickness of the preform. Using CIRTM, a phenolic surface layer may be incorporated with a vinyl ester resin in a single composite part, improving fire performance while maintaining the cost, processing and structural advantages of the vinyl ester. Through this program, preliminary property characterization of fire-hard CIRTM components will be accomplished through the fabrication of 2'x2' test panels. In addition, we will demonstrate that the benefits of the CIRTM process can be scaled up for realistic Naval structural applications. In Phase II a half scale deck house will be fabricated.