Abstract: The present disclosure provides a series of new and improved porous polyamide aerogels derived from multifunctional aromatics that combine the high mechanical strength of aramids with the pore structure of aerogels. The polyamide aerogels have a hyperbranched structure, relatively low density, high porosity and are derived from functionalized monomers having more aromatic groups than functional groups. The present disclosure also provides a new method for producing the porous polyamide aerogels by polymerizing an aromatic multifunctional carboxylic acid with an isocyanate at moderate reaction condition followed by drying with liquid CO2.

Abstract: Porous three-dimensional networks of polyimide and porous three-dimensional networks of carbon and methods of their manufacture are described. For example, polyimide aerogels are prepared by mixing a dianhydride and a diisocyanate in a solvent comprising a pyrrolidone and acetonitrile at room temperature to form a sol-gel material and supercritically drying the sol-gel material to form the polyimide aerogel. Porous three-dimensional polyimide networks, such as polyimide aerogels, may also exhibit a fibrous morphology. Having a porous three-dimensional polyimide network undergo an additional step of pyrolysis may result in the three dimensional network being converted to a purely carbon skeleton, yielding a porous three-dimensional carbon network. The carbon network, having been derived from a fibrous polyimide network, may also exhibit a fibrous morphology.

Abstract: The present disclosure provides a series of new and improved porous polyamide aerogels derived from multifunctional aromatics that combine the high mechanical strength of aramids with the pore structure of aerogels. The polyamide aerogels have a hyperbranched structure, relatively low density, high porosity and are derived from functionalized monomers having more aromatic groups than functional groups. The present disclosure also provides a new method for producing the porous polyamide aerogels by polymerizing an aromatic multifunctional carboxylic acid with an isocyanate at moderate reaction condition followed by drying with liquid CO2.

Abstract: A composite material that includes a dopant comprised of pre-formed, three dimensional assemblies of skeletal structures that are comprised of solgel derived nanoparticles. The composite material includes a chemically bonded, in situ formed, polymer coating that at least partially coats mesoporous surfaces of the nanoparticles to provide enhancement of random dispersion of the dopant and to minimize or avoid agglomeration. Further, the polymer may be functionalized or the mesoporous surfaces of the nanoparticles may be treated to enable stronger chemical bonding between the dopant and the polymer.

Abstract: Cross-linked sol-gel like materials and cross-linked aerogels, as well as methods for making such cross-linked sol-gel like materials and cross-linked aerogels are described.

Abstract: Porous three-dimensional networks of polyurea and porous three-dimensional networks of carbon and methods of their manufacture are described. In an example, polyurea aerogels are prepared by mixing an triisocyanate with water and a triethylamine to form a sol-gel material and supercritically drying the sol-gel material to form the polyurea aerogel. Subjecting the polyurea aerogel to a step of pyrolysis may result in a three dimensional network having a carbon skeleton, yielding a carbon aerogel. The density and morphology of polyurea aerogels can be controlled by varying the amount of isocyanate monomer in the initial reaction mixture. A lower density in the aerogel gives rise to a fibrous morphology, whereas a greater density in the aerogel results in a particulate morphology. Polyurea aerogels described herein may also exhibit a reduced flammability.

Abstract: Porous three-dimensional networks of polyimide and porous three-dimensional networks of carbon and methods of their manufacture are described. For example, polyimide aerogels are prepared by mixing a dianhydride and a diisocyanate in a solvent comprising a pyrrolidone and acetonitrile at room temperature to form a sol-gel material and supercritically drying the sol-gel material to form the polyimide aerogel. Porous three-dimensional polyimide networks, such as polyimide aerogels, may also exhibit a fibrous morphology. Having a porous three-dimensional polyimide network undergo an additional step of pyrolysis may result in the three dimensional network being converted to a purely carbon skeleton, yielding a porous three-dimensional carbon network. The carbon network, having been derived from a fibrous polyimide network, may also exhibit a fibrous morphology.

Abstract: Three-dimensional nanoporous aerogels and suitable preparation methods are provided. Nanoporous aerogels may include a carbide material such as a silicon carbide, a metal carbide, or a metalloid carbide. Elemental (e.g., metallic or metalloid) aerogels may also be produced. In some embodiments, a cross-linked aerogel having a conformal coating on a sol-gel material is processed to form a carbide aerogel, metal aerogel, or metalloid aerogel. A three-dimensional nanoporous network may include a free radical initiator that reacts with a cross-linking agent to form the cross-linked aerogel. The cross-linked aerogel may be chemically aromatized and chemically carbonized to form a carbon-coated aerogel. The carbon-coated aerogel may be suitably processed to undergo a carbothermal reduction, yielding an aerogel where oxygen is chemically extracted. Residual carbon remaining on the surface of the aerogel may be removed via an appropriate cleaning treatment.

Abstract: Cross-linked sol-gel like materials and cross-linked aerogels, as well as methods for making such cross-linked sol-gel like materials and cross-linked aerogels are described.

Abstract: A composite material that includes a dopant comprised of pre-formed, three dimensional assemblies of skeletal structures that are comprised of solgel derived nanoparticles. The composite material includes a chemically bonded, in situ formed, polymer coating that at least partially coats mesoporous surfaces of the nanoparticles to provide enhancement of random dispersion of the dopant and to minimize or avoid agglomeration. Further, the polymer may be functionalized or the mesoporous surfaces of the nanoparticles may be treated to enable stronger chemical bonding between the dopant and the polymer.

Abstract: A bidentate free radical crosslinking initiator binds chemically to silica and silica rich surfaces and enables the free radical based polymerization of various materials such as styrene, divinylbenzene and methylmethacrylate onto silica and silica rich surfaces. When used in connection with aerogels, the resultant crosslinked aerogels exhibit greatly increased strength with only nominal increase in density.

Abstract: Macroporous monolithic silica aerogels having mesoporous walls are produced via an acid-catalyzed sol-gel process from tetramethoxysilane (TMOS) using a triblock co-polymer (Pluronic P123) as a structure-directing agent and 1,3,5-trimethylbenzene (TMB) as a micelle-swelling reagent. Pluronic P 123 was removed by solvent extraction, and monoliths were obtained by removing the pore-filling solvent with liquid CO2, which was removed under supercritical conditions. The resulting materials are more robust compared to base-catalyzed silica aerogels of similar density. Mechanical properties can be further improved by reacting a di-isocyanate with the silanol groups on the macro and mesoporous surfaces. The polymer forms a conformal coat on the macropores and blocks access to the mesopores of templated samples, so that BET surface areas decrease dramatically.

Abstract: Novel acridinium esters that are useful, either alone or when incorporated into liposomes, as chemiluminescent agents in binding assays (e.g., immunoassays and gene probe assays) with improved-sensitivity are disclosed. In addition, the synthesis of these esters and their use in assays for detecting an analyte is described. In particular, assays for testosterone and the Rubella virus are disclosed.