A method of forming a void, channel and/or vascular network in a polymeric matrix comprises providing a pre-vascularized structure that includes a matrix material and a sacrificial material embedded in the matrix material in a predetermined pattern, where the matrix material comprises a monomer and the sacrificial material comprises a polymer. A region of the matrix material is activated to initiate an exothermic polymerization reaction and generate a self-propagating polymerization front. As the polymerization front propagates through the matrix material and polymerizes the monomer, heat from the exothermic reaction simultaneously degrades the sacrificial material into a gas-phase and/or liquid-phase byproduct. Thus, one or more voids or channels having the predetermined pattern are rapidly formed in the matrix material.

High-temperature polymer aerogel composites, associated materials, associated methods of manufacture, and applications of polymer aerogel composites including engine covers comprising aerogel materials are generally described.

Polyurethane foams and methods of manufacturing are described herein. The foam can include (a) a polyurethane formed by the reaction of (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, and (ii) one or more polyols; and (b) a filler. The amount of filler in the foam can be from 50 to 90% by weight, based on the total weight of the foam. The filler can include a plurality of fibers and/or a particulate filler. The polyurethane foams described herein are made without adding a surfactant to the reaction mixture. The density of the polyurethane foam can be at least 5 lb/ft.sup.3.

Disclosed are porous elements that include sintered polymeric particles. The polymeric particles can be formed of a thermoplastic composition that includes a polyarylene sulfide. The polymeric particles sintered to form the porous elements have a very narrow size distribution. The porous elements can maintain their functionality and morphology even when utilized in high temperature applications.

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 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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The present invention relates to a method of making a foamed cellulosic fiber-thermoplastic composite article. The method includes the steps of providing a copolymer composition, combining the copolymer composition and cellulosic fibers, applying heat, mixing energy and pressure to form a foamable mixture, and forming the foamable article in a molding or extruding operation. The method is characterized in that at least 10% of the cellulosic fibers have been thermally modified prior to being combined with the copolymer composition.

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 structure for protecting a substrate. The structure comprises an inner tie coat layer which can bond to the substrate, a geopolymer foam layer, and an outer protective layer. The geopolymer foam layer is the reaction product of a mixture comprising an aluminosilicate source, an alkali activator, reinforcing fibres, and a plurality of microparticles.

Polyurethane foams and methods of manufacturing are described herein. The foam can include (a) a polyurethane formed by the reaction of (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, and (ii) one or more polyols; and (b) a filler. The amount of filler in the foam can be from 50 to 90% by weight, based on the total weight of the foam. The filler can include a plurality of fibers and/or a particulate filler. The polyurethane foams described herein are made without adding a surfactant to the reaction mixture. The density of the polyurethane foam can be at least 5 lb/ft.sup.3.