Advanced Flame Resistant Resin System for Carbon Fiber Reinforced Composite Shipboard Applications

Efforts to replace metals with composites in shipboard applications have emphasized the use of brominated vinyl esters as fire-retardant polymers. Despite their relatively low cost and ease of fabrication, such halogenated polymers produce toxic and potentially carcinogenic gases; their compatibility with carbon fibers is also less than desirable. There is thus a need for environmentally friendly and affordable polymers that offer desired fire resistance, processability, structural performance and compatibility with carbon fibers. This challenge is addressed in the project by developing a modified epoxy chemistry which employs the organic-inorganic hybridization principle. Chemical integration of phosphorus- and silicon-based compounds into selected epoxy systems yielded a single, inherently flame-retardant polymer structure with a desired balance of fire, smoke and toxicity behavior, compatibility with the resin-infusion approach to room-temperature processing of composites, thermo-mechanical performance, bonding characteristics, and economics. The Phase II project will optimize this modified epoxy chemistry, and will undertake laboratory investigations and scale-up efforts towards qualification of the new polymer composite for use in shipboard structures. The proposed project will be implemented in a base (Phase II) and two option steps, and will be guided by the experience gained in successful qualification of composites for use in Naval surface combatants.