Aerogels comprising a hydrophobic polyimide moiety, including hydrophobic polyimide aerogels, as well as methods of manufacture and applications thereof, are generally described.

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Drying polar solvents which do not form hydrogen bonds with a wet gel or aerogel, or eutectics or solvent mixtures with the drying solvents, are utilized in a solvent exchange with wet gels used in the formation of aerogels. Preferably the drying solvents are non-polar solvents. The drying solvent or solvent mixtures results in profoundly less shrinkage, thereby allowing for the production of aerogels of preferred materials properties.

The invention is directed to biomedical polyurethanes. The invention is particularly directed to biomedical polyurethanes with improved biodegradability and to an improved preparation of the biomedical polyurethanes. In particular the present invention provides a biomedical polyurethane having the formula (A-B-C-B).sub.n, wherein A denotes a polyol, B denotes a diisocyanate moiety, C denotes a diol component and n denotes the number of recurring units, and wherein the B-C-B segment is bioresorbable.

An aerogel that includes an open-cell structured polymer matrix is disclosed. The aerogel includes 5 wt. % to 50 wt. % of a polyamic amide polymer, based on the total weight of the aerogel, pores and at least 90% of the pore volume of the aerogel is made up of macropores, a porosity of at least 50%, as measure according to ASTM D4404-10, a density of 0.01 g/cm.sup.3 to 0.5 g/cm.sup.3, and the aerogel is thermally stable to resist browning at 330° C.

Aerogel compositions that include polyamic amides, methods for preparing the aerogel compositions, and articles of manufacture that include or manufactured from the aerogel compositions are described.

An aerogel that includes an open-cell structured polymer matrix that can have 5 wt. % to 50 wt. % of a polyamic amide polymer, based on the total weight of the aerogel is disclosed. The aerogel can have a density of 0.05 g/cm.sup.3 to 0.35 g/cm.sup.3 and can be thermally stable to resist browning at 330° C.

Aerogel compositions, methods for preparing the aerogel compositions, articles of manufacture that include or are made from the aerogel compositions are described and uses thereof. The aerogels include a branched polyimide matrix with little to no crosslinked polymers.

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.

The present disclosure is directed to methods of forming polyimide gels. The methods generally include forming a polyamic acid and dehydrating the polyamic acid with a dehydrating agent in the presence of water. The resulting polyimide gels may be converted to polyimide or carbon xerogels or aerogels. The methods are advantageous in providing rapid or even instantaneous gelation, which may be particularly useful in formation of beads comprising the polyimide gels. Polyimide or carbon gel materials prepared according to the disclosed method are suitable for use in environments containing electrochemical reactions, for example as an electrode material within a lithium-ion battery.

Systems and methods for producing aerogel materials are generally described. In certain cases, the methods do not require supercritical drying as part of the manufacturing process. In some cases, certain combinations of materials, solvents, and/or processing steps may be synergistically employed so as to enable manufacture of large (e.g., meter-scale), substantially crack free, and/or mechanically strong aerogel materials.