Mechanically strong, biodegradable and reusable aerogels are disclosed, which can be made with a cross-linked cellulose ester, and which exhibit a low density and high porosity. The aerogels disclosed herein may be used as sorbent materials and can be modified with a hydrophobic and/or oleophilic agent.

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.

Organic polymer aerogels, articles of manufacture, and uses thereof are described. The aerogels include an organic polymer matrix and microstructures dispersed within the aerogels, which provides for superior thermal conductivity and mechanical properties.

A porous polymer aerogel, wherein the aerogel has greater than 5 wt % of amine containing vinyl monomers integrated into a polymer backbone. A method of fabrication of a porous polymer aerogel amine material, includes preparing a solution comprising at least a solvent, amine monomers having protected amino groups, one or more crosslinkers, one or more radical initiators, and a nitroxide mediator, removing oxygen from the solution, heating the solution to promote polymerization and to produce a polymerized material, performing solvent exchange with the polymerized material, causing a deprotection reaction in the polymerized material to remove groups protecting the amino groups, soaking and rinsing the material to remove excess reagents and any byproducts of the deprotection reaction, and drying the material to produce the amine sorbent. A system to separate CO2 from other gases, comprising a polymer porous aerogel sorbent having greater than 5 wt % of amine containing vinyl monomers integrated into a polymer backbone.

The present application relates to copolymer-silica hybrid aerogels as well as methods for the preparation thereof. The methods comprise hydrolyzing a silica precursor in an organic solvent to obtain a partially polymerized silica wet gel, reacting the partially polymerized silica wet gel with a copolymer of Formula (II) to obtain a copolymer-silica hybrid wet gel, reacting the copolymer-silica hybrid wet gel with a surface passivation agent and removing solvent from the copolymer-silica hybrid wet gel to obtain the copolymer-silica hybrid aerogel. The mechanical properties of the copolymer-silica hybrid aerogels can be further improved by blending cellulose nanofibrils into the hybrid aerogels. (II)

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Formation of low-crystallinity phytosterol nanoparticles via cooling-controlled supercritical carbon dioxide (SC—CO.sub.2) impregnation of phytosterols into biodegradable nanoporous starch aerogels and methods of preparing these aerogels are disclosed. The nanoporous starch aerogels increase water dissolution and bioaccessibility of the phytosterols, thereby making them available for preparation of high nutraceutical value foods.

The present disclosure provides a method for preparing an aerogel or a foam, the method comprising: forming a reaction mixture comprising a cellulose nanofibril gel, a first solvent, and one or more crosslinking agents under conditions sufficient to crosslink the gel; and contacting the crosslinked gel with a second solvent under conditions sufficient to dry the crosslinked gel, thereby forming an aerogel or foam.

A molding based on a monolithic organic aerogel has a density in the range from 60 to 300 kg/m.sup.3 and a thermal conductivity in the range from 12 to 17.8 mW/m*K. The molding based on a monolithic organic aerogel has more than 30 vol.-% of pores with a diameter of less than 150 nm, and more than 20 vol.-% of pores with a diameter of less than 27 nm, based on the total pore volume. A process can be used to prepare the molding by compression.

A method of manufacturing a thermally insulating product comprises: (a) forming a mixture comprising solvent and gel network former and optionally foaming agent; (b) dispersing a thermally insulating filler in the mixture; and (c) drying the mixture to form the thermally insulating product.

The present disclosure is directed to methods of forming polyamic acid and polyimide gels in water. The resulting polyamic acid and polyimide gels may be converted to aerogels, which may further be converted to carbon aerogels. Such carbon aerogels have the same physical properties as carbon aerogels prepared from polyimide aerogels obtained according to conventional methods, i.e., organic solvent-based. The disclosed methods are advantageous in reducing or avoiding costs associated with use and disposal of potentially toxic solvents and byproducts. Gel materials prepared according to the disclosed methods are suitable for use in environments involving electrochemical reactions, for example as an electrode material within a lithium-ion battery.