摘要 |
<p>There is disclosed a polyurethane/unsaturated polyester hybrid foam of the rigid type prepared from novel components including not only polyol and polyisocyanate but also a unique hydroxy-containing vinyl ester and vinyl monomer, optionally together with an additional polar vinyl monomer, all together providing the necessary components for a hybrid polyurethane-polyvinyl ester matrix, which mixture of components before foaming is capable of having suspended therein fillers and reinforcing fibers to produce a foam or reinforced foam composite having a density between about 20 and 100 pounds per cubic foot. The reinforced foam can be made into baords and the like and advantageously has continuous fiberglass strands or yarn disposed longitudinally in or adjacent the surface skin of the foam. The strands or yarn are preferably parallel and close together and are preferably flattened out in the foam-forming process so that the surfaces have a continuous fiberglass implant longitudinally and substantially so transversely. One preferred structural composite is illustrated in the drawings.</p> |