BRANCHES FILTERING APPROACH FOR MAX-TREE

A composition is disclosed in which a solid isocyanate compound such as toluene-diisocyanate dimer is dispersed within a polyurethane based on a hydroxy-terminated organic compound, preferably polybutadiene. The composition can be fully cured on a surface and yet provides an excess of stable material, i.e. dormant isocyanate containing groups, which are reactive on demand to strengthen interfaces with adjacent layers containing available hydroxyl groups, such as a layer of solid polyurethane-based propellant, without the need for intermediate reactive coatings.