Abstract: A method of filling a seam of a structural panel assembly utilizes a non-foaming, thixotropic, two-component polyurethane elastomeric material. The thixotropic, elastomeric material is prepared by rapidly mixing and initiating the reaction of a first thixotropic component comprising an isocyanate-terminated compound having at least two reactive isocyanate groups and a second thixotropic component comprising a hydroxyl-terminated compound having at least two reactive hydroxyl groups. Each of the first and second thixotropic components include from about 3% to 8% by weight fumed silica. The second thixotropic component also includes from about 10% to about 50% filler. The thixotropic elastomeric material is applied over the seam of a panel assembly. The method then includes fluidizing the thixotropic elastomeric material and driving the thixotropic elastomeric material into the seam of the panel assembly.

Abstract: This invention relates to a flame-retardant polyurethane spray system prepared by mixing at an isocyanate index of from 90 to 120(A) an isocyanate composition containing(a) an organic polyisocyanate, and(b) 0 to 50 wt. %, relative to the organic polyisocyanate, of a halogen-containing organic flame retardant; and(B) an isocyanate-reactive composition containing(a) 10 to 80 wt. % of an isocyanate-reactive compound having a molecular weight of 400 to 10,000 and functionality of 2 to 7;(b) 1 to 50 wt. % of an isocyanate-reactive compound having a molecular weight less than 399 and functionality of 2 to 6;(c) 0 to 15 wt. % of an isocyanate-reactive tertiary amine polyether having a molecular weight of 100 to 1000;(d) 5 to 55 wt.

Abstract: A cap for sealing waste in a landfill is prepared by disposing a fill layer atop the waste and applying a fast-curing elastomeric material to the fill layer to provide a monolithic, continuous, elastomeric coating thereupon. The elastomeric material is derived from the reaction of an isocyanate-terminated compound having at least two reactive isocyanate groups and an amine-terminated compound having at least two reactive amine groups. The elastomeric layer is preferably covered with a porous drainage layer which is in turn covered with a layer of soil.

Abstract: This invention relates to a method of repairing existing manholes and similar structures by applying a fast-curing elastomeric material using spray techniques whereby a homogeneous, non-porous, and monolithic coating or lining is formed. The fast-curing elastomeric material can be applied directly to existing substrates, which may comprise of concrete, brick, tile, mortar, and metal surfaces normally found in sewer manholes and catch basins, sewer and drainage pipes, parking decks, bridge piers and footings, holding ponds, bridge trusses, culverts, gratings, and the like and does not require any formwork. More preferably, the substrate surfaces are first cleaned and primed to improve the bond of elastomeric coating to the substrate. The most preferred primer is an aqueous solution of silane, preferably containing 10% to 30% silane.

Abstract: This invention relates to a method of repairing existing manholes and similar structures by applying a fast-curing elastomeric material using spray techniques whereby a homogeneous, non-porous, and monolithic coating or lining is formed. The fast-curing elastomeric material can be applied directly to existing concrete, brick, tile, mortar, and metal surfaces normally found in sewer manholes and catch basins, sewer and drainage pipes, parking decks, bridge piers and footings, holding ponds, bridge trusses, culverts, gratings, and the like and does not require any formwork. The elastomeric coatings provide effective surface protection against wear, corrosion, and water infiltration and can be applied in a single operation to horizontal, vertical, and overhead surfaces.