Abstract An open-pore polyurethane structure containing powdered metal comprising coherent spherical particles separated by interconnected interstices and a method of producing this structure comprising mixing metal powder with the components to make a polyurethane structure in a container, polymerizing the mixture in place without stirring after onset of gelation. The polyurethane can be removed preferably by heating in air at a temperature below the sintering temperature for the metal, and the remaining metal can then be sintered forming a sintered porous metal or metal oxide structure depending on the metal used and sintering conditions. A number of porous nickel products were made by the process of the invention and after the removal of the polyurethane depending on the particle size of the nickel and the amount and conditions of sintering densities of the products ranged from 1 to 5 g./cc., compressive strengths from 100 to 20,000 and porosity from 20 to 80 percent. The porous metals or sintered porous metals can be used in mechanical support, air and liquid filters, porous bearings, porous electrodes, acoustic filters, impact absorbers, capillary wicks, void fillers, integral conductor-insulator rods, and three-dimensional highmodulus reinforcements.
A POROUS METAL STRUCTURE MADE BY HEATING AT A SUFFICIENT TEMPERATURE TO REMOVE THE POLYURETHANE AN OPEN-PORE POLYURETHANE STRUCTURE CONTAINING POWDERED METAL DISPERED IN SAID POLYURETHANE, SAID STRUCTURE COMPRISING COHERENT, ROUGHLY SPHERICCAL POLYURETHANE PARTICLES CONTAINING SAID POWDERED METAL, SAID SPHERICAL PARTICLES STICKING TOGETHER IN AN INTERCONNECTED MATRIX, AND IN WHICH THE POLYURETHANE IS THE PRODUCT OF THE REACTION BETWEEN A. A MIXTURE OF POLYARYL POLYALKYLENE POLYISOCYANATES HAVING THE FORMULA
Claim 2
Dependent Claim
69 words
A POROUS METAL STRUCTURE MADE BY HEATING AT A SUFFICIENT TEMPERATURE TO REMOVE THE POLYURETHANE AN OPEN-PORE POLYURETHANE STRUCTURE CONTAINING POWDERED METAL DISPERED IN SAID POLYURETHANE, SAID STRUCTURE COMPRISING COHERENT, ROUGHLY SPHERICCAL POLYURETHANE PARTICLES CONTAINING SAID POWDERED METAL, SAID SPHERICAL PARTICLES STICKING TOGETHER IN AN INTERCONNECTED MATRIX, AND IN WHICH THE POLYURETHANE IS THE PRODUCT OF THE REACTION BETWEEN A. A MIXTURE OF POLYARYL POLYALKYLENE POLYISOCYANATES HAVING THE FORMULA