Flammability properties of polymer matrix composites for marine applications

This paper describes the research and development effort to determine the feasibility of using advanced fire safe polymeric materials for structural applications inside the pressure hull of Navy submarines. This phase of the work consists of addressing serious technical issues that have limited the use of composites inside submarines. These issues are flammability, smoke, and toxic gas emissions of polymer matrix composites. Four glass-reinforced and one carbon-reinforced composites were fabricated using four different resin systems. They were tested under the Cone Calorimeter test per MIL-STD-2031, "Fire and Toxicity Test Methods and Qualification procedure for Composite Material Systems Used in Hull, Machinery, and Structural Applications Inside Naval Submarines [1]". All five composites performed quite well under these severe conditions. The Ciba Specialty Chemicals RD98-228 cyanate ester and the Naval Research Laboratory phthalonitrile glass-reinforced composites met the MIL-STD-2031 requirements for sustained time of ignition, peak heat release rate and average heat release rate for 300s at all heat fluxes.