US Patent 8211331 Packaged reactive materials and method for making the same

A packaged reactive material includes a reactive material that is configured to increase in size when exposed to a predetermined gas, and an inert coating material surrounding a surface of the reactive material. The inert coating material is configured to allow the predetermined gas to diffuse through to the reactive material and has an elongation that will not accommodate expansion of the reactive material at full saturation of the predetermined gas.