Porous polyurethane networks and methods of preparation

Abstract

Nanoporous three-dimensional networks of polyurethane particles, e.g., polyurethane aerogels, and methods of preparation are presented herein. Such nanoporous networks may include polyurethane particles made up of linked polyisocyanate and polyol monomers. In some cases, greater than about 95% of the linkages between the polyisocyanate monomers and the polyol monomers are urethane linkages. To prepare such networks, a mixture including polyisocyanate monomers (e.g., diisocyanates, triisocyanates), polyol monomers (diols, triols), and a solvent is provided. The polyisocyanate and polyol monomers may be aliphatic or aromatic. A polyurethane catalyst is added to the mixture causing formation of linkages between the polyisocyanate monomers and the polyol monomers. Phase separation of particles from the reaction medium can be controlled to enable formation of polyurethane networks with desirable nanomorphologies, specific surface area, and mechanical properties. Various properties of such networks of polyurethane particles (e.g., strength, stiffness, flexibility, thermal conductivity) may be tailored depending on which monomers are provided in the reaction.

What is claimed is: 
     
         1 - 29 . (canceled) 
     
     
         30 . A method of making a carbon network, comprising:
 combining a polyisocyanate, a polyol, a solvent, and a catalyst to form a gel;   drying the gel to form a polyurethane network, said polyurethane network exhibiting a fibrous morphology; and   pyrolyzing the polyurethane network to form the carbon network.   
     
     
         31 . The method of  claim 30 , wherein the drying comprises subcritical drying. 
     
     
         32 . The method of  claim 30 , wherein the drying comprises supercritical drying. 
     
     
         33 . The method of  claim 30 , wherein the polyurethane network comprises an aromatic polymer comprising at least two aromatic rings with no more than one carbon between the aromatic rings. 
     
     
         34 . The method of  claim 30 , wherein the polyisocyanate comprises at least two aromatic rings with no more than one carbon between the aromatic rings. 
     
     
         35 . The method of  claim 30 , wherein the polyol comprises at least two aromatic rings with no more than one carbon between the aromatic rings. 
     
     
         36 . A carbon network produced by the method of  claim 30 . 
     
     
         37 . An electrode, supercapacitor, or catalyst support comprising the carbon network of  claim 31 . 
     
     
         38 . A polyurethane aerogel comprising aromatic rings, the polyurethane aerogel comprising no more than one carbon between the aromatic rings. 
     
     
         39 . A carbonized material made from the polyurethane aerogel of  claim 38 . 
     
     
         40 . An electrode, supercapacitor, or catalyst support comprising the carbonized material of  claim 39 . 
     
     
         41 . A polyurethane aerogel exhibiting a fibrous morphology. 
     
     
         42 . A carbonized derivative of the polyurethane aerogel of  claim 41 . 
     
     
         43 . An electrode, supercapacitor, or catalyst support comprising the carbonized derivative of  claim 42 .