Next Generation Buoyancy Material

A hybrid buoyancy foam is proposed, consisting of new technology lightweight macrospheres in a matrix of closed-cell blown foam. The hybrid composite, with a target density of 0.05 g/cm3, will combine the compressive strength and stiffness of macrospheres with the resilience of a blown foam to meet the specified threshold performance properties. The macrospheres will be manufactured using thin film UV-curable core- shell rubber modified vinyl ester technology for damage tolerance, with Boron Nitride Nanotubes reinforcement. These will be closely packed in highly ordered binary arrays using additive layering techniques for maximum volume packing factor in virtually net shapes. The macrospheres will be encapsulated with BNNT or carbon reinforced rigid polyurethane or BPA/BPF epoxy blown foam as a binder, engineered for high modulus and resilience in the ocean temperature range. Phase I will develop macrosphere manufacturing, grading and assembly processes and blown foam formulation, resulting in a laboratory-scale composite for property testing. Phase I Option will work on refining properties and scaling up processes for full-scale production in a Phase II. Potential technology offshoots include a high-performance syntactic foam with unprecedented strength and moduli for given density, as well as a pure blown foam of high stiffness and resilience