Rigid polyurethane/polyisocyanurate foams containing paraffinic based oils

摘要

The invention is a rigid polyurethane foam to which a base stock lubricating oil made of at least 55 weight percent paraffinic carbons and less than 10 weight percent aromatic carbons has been added as a hydrophobic agent protecting the polyurethane foam from reacting with environmental moisture. The foam is useful for deposit in railroad spike holes or any structural member having a cavity and where moisture within or on the cavity would otherwise react with the isocyanate to produce an uncontrollable foaming mass.