A product includes an aerogel having a single bulk structure, the single bulk structure having at least one dimension greater than 10 millimeters. The single bulk structure includes a plurality of pores, where each pore has a largest diameter defined as a greatest distance between pore walls of the respective pore. In addition, an average of the largest diameters of a majority of the pores is within a specified range, and the plurality of pores are distributed substantially homogenously throughout the single bulk structure.

Inorganic infrared attenuation agent blends have been developed to improve the thermal insulation properties of polymeric foams such as polystyrene low density foams. The inorganic infrared attenuation agent blends can include two or more metal oxides such as silicon dioxide, manganese (IV) oxide, iron (III) oxide, magnesium oxide, bismuth (III) oxide, cobalt oxide, zirconium (IV) oxide, molybdenum (III) oxide, titanium oxide, and calcium oxide. In some preferred embodiments, the inorganic infrared attenuation agent blends can include four or more of these metal oxides.

A compact, highly expandable sorbent made from polymeric materials is contemplated. The resulting sorbent can absorb more than 20 times its original volume owing to an internal foam-like structure having micron-level voids bisected by internal struts which themselves have nano-level pores. Further, this sorbent can be compressed and reused multiple times, thereby making it an ideal substance to facilitate separation of disparate fluids, such as oils floating on or within an aqueous solution.

A material for making an underlayment of a floor includes a thermoplastic polymer that has a thickness and a microstructure. The microstructure includes a plurality of closed cells, each cell containing a void and each cell having a maximum dimension extending across the void within the cell that is less than or equal to 200 micrometers long. The microstructure also includes a density that is greater than or equal to 0.18 grams per cubic centimeter.

A HIPE foam may including a vinyl-based crosslinked polymer as a base material resin. The vinyl-based crosslinked polymer may be formed by crosslinking a polymer of a styrene-based monomer and/or an acryl-based monomer. An apparent density ρ of the HIPE foam may be 35 kg/m.sup.3 or more and 500 kg/m.sup.3 or less. A molecular weight between crosslinking points of the vinyl-based crosslinked polymer forming the HIPE foam may be 2×10.sup.3 or more and 2×10.sup.5 or less. The HIPE foam may be used as, for example, a machinable material or an impact absorbing material.

A resin sheet includes the porous structure. The porous structure is configured to adjust transmission of a millimeter wave. The porous structure has a relative permittivity varying in a thickness direction of the resin sheet such that a difference between average relative permittivities in two adjacent layer portions is a predetermined value or less, the layer portions each having a particular thickness smaller than a wavelength of the millimeter wave. The porous structure includes a boundary portion being one of the layer portions, the boundary portion having a maximum average relative permittivity. The relative permittivity increases in stages from end portions of the porous structure toward the boundary portion, the end portions being defined in the thickness direction of the resin sheet.

A composite material according to the present invention includes a solid portion including inorganic particles and a resin. The composite material has a porous structure including a plurality of voids surrounded by the solid portion. The composite material has a heat conductivity of 0.5 W/(m.Math.K) or more and a spring constant of 100 N/m to 70,000 N/m. The heat conductivity is a value measured for one test specimen in a symmetric configuration according to an American Society for Testing and Materials (ASTM) standard D5470-01.

A method for preparing a thermoplastic polyurethane elastomer material with micro air holes is provided. The method comprises the following steps: (1) is feeding liquid raw materials such as diisocyanate molecules and solid additives into a double-screw reactor to trigger a polymerization type chain extension reaction and then obtain a macromolecular weight hot melt. (2) is pushing the macromolecular weight hot melt into a mixing extruder and allowing the reaction to continue to obtain a macromolecular thermoplastic polyurethane melt. (3) is continuously adding the obtained macromolecular thermoplastic polyurethane melt together with polymer particles into a foaming extruder, and extruding the high-pressure hot melt from a mold head into an underwater granulation chamber. (4) is delivering the particles obtained after granulation into a separator by process water via a multi-stage pressure-release process water pipeline, separating, screening and drying the required particles to obtain the target product.

An expanded beads molded article containing a block copolymer of a polyethylene block and an ethylene-α-olefin copolymer block and having a density of 150 kg/m.sup.3 or more and 500 kg/m.sup.3 or less and a tensile strength of 0.5 MPa or more.

Provided is a material having an excellent sound-absorbing performance which can be easily applied to the desired area at the operation site and which can effectively prevent sound leakage. The material includes an open-cell soft polyurethane foam prepared from a 2-part reactive urethane resin composition prepared from a polyisocyanate component and a polyol-containing component, wherein the polyol-containing component comprises a polyol component, catalysts, a foam stabilizer, an amine compound having primary or secondary amino groups, and carbon dioxide; wherein an average sound absorption coefficient of said polyurethane foam is 30% or more, measured in accordance with JIS A 1405-2:2007 for 63 hertz to 5000 hertz; and the length of liquid-dripping is within 300 mm.