Abstract: The present invention relates to a process for producing a foamed material, wherein a composition in the form of emulsion with a matrix-forming component, a surfactant component and a near-critical or supercritical blowing agent component is submitted to a lowering of pressure. The blowing agent component further comprises a hydrophobic co-component, which is soluble in supercritical CO2 at a pressure of ?150 bar, is insoluble in subcritical CO2 at a pressure of ?40 bar and is insoluble in the matrix-forming component and furthermore is present in a proportion from ?3 wt % to ?35 wt % of the blowing agent component. It further relates to a composition in the form of emulsion to be used herein and a foamed material obtainable by the process according to the invention.

Abstract: A structural element with a controllable heat transfer coefficient comprises a frame. A first sheet and a second sheet opposite one another are arranged in the frame. The sheets and the frame have the effect of defining a closed-off volume which is filled with at least one gas. At least one two-dimensional element is arranged between the sheets. An upper intermediate space is formed between the two-dimensional element and the frame vertically upwardly and a lower intermediate space is formed between the two-dimensional element in the frame vertically downwardly. A first cavity is between the first sheet and the two-dimensional element. A second cavity is between the two-dimensional element and the second sheet. The cavities are connected via the upper intermediate space and the lower intermediate space such that a convection flows between the cavities via the intermediate spaces. At least one means arranged in the intermediate spaces controls the convection flow.

Abstract: The invention relates to a vacuum insulation panel comprising a barrier film and a core material having a density in the range from 50 to 350 kg/m3, wherein the core material comprises a mixture of A) from 30 to 100 percent by weight of nanoporous polymer particles which have a cell count in the range from 1000 to 100 000 cells/mm, where at least 60 percent by weight of the nanoporous polymer particles have a particle size of less than 100 ?m in the sieve analysis in accordance with DIN 66165, and B) from 0 to 70 percent by weight of pyrogenic or precipitated silica, and also a process for the production thereof.

Abstract: The present invention relates to a process for producing a polyurethane foam, where the blowing agent used is present in the supercritical or near-critical state. A reaction mixture is introduced into a closed mould, where the closed mould has been set up in such a way that its interior volume and/or the pressure prevailing in its interior can be altered after the introduction of the mixture by external influence. Through the selection of the surfactant it is possible to obtain microemulsions of the blowing agent in the polyol phase. The invention further relates to a nanocellular polyurethane foam obtainable by the process of the invention.

Abstract: A process for producing a polyurethane foam with bimodal cell size distribution, comprising the following steps: providing a mixture in a mixing head, where the mixture comprises: A) a component reactive towards isocyanates; B) a surfactant component; C) a blowing agent component selected from the group consisting of linear, branched or cyclic C1- to C6-alkanes, linear, branched or cyclic C1- to C6-fluoroalkanes, N2, O2, argon and/or CO2, where blowing agent component C) is present in the supercritical or near-critical state; D) a polyisocyanate component; discharging the mixture comprising components A), B), C), and D) from the mixing head where, during the discharge of the mixture, the pressure prevailing in the mixture is lowered to atmospheric pressure.

Abstract: Process for producing a polyurethane foam and polyurethane foam obtainable therefrom A process for producing a polyurethane foam with bimodal cell size distribution, comprising the following steps: providing a mixture in a mixing head, where the mixture comprises: A) a component reactive towards isocyanates; B) a surfactant component; C) a blowing agent component selected from the group consisting of linear, branched or cyclic C1- to C6-alkanes, linear, branched or cyclic C1- to C6-fluoroalkanes, N2, O2, argon and/or CO2, where blowing agent component C) is present in the supercritical or near-critical state; D) a polyisocyanate component; discharging the mixture comprising components A), B), C), and D) from the mixing head where, during the discharge of the mixture, the pressure prevailing in the mixture is lowered to atmospheric pressure.

Abstract: The present invention relates to a process for producing a foamed material, wherein a composition in the form of emulsion with a matrix-forming component, a surfactant component and a near-critical or supercritical blowing agent component is submitted to a lowering of pressure. The blowing agent component further comprises a hydrophobic co-component, which is soluble in supercritical CO2 at a pressure of ?150 bar, is insoluble in subcritical CO2 at a pressure of ?40 bar and is insoluble in the matrix-forming component and furthermore is present in a proportion from ?3 wt % to ?35 wt % of the blowing agent component. It further relates to a composition in the form of emulsion to be used herein and a foamed material obtainable by the process according to the invention.

Abstract: The present invention relates to a reaction mixture in emulsion form, suitable for conversion into polyurethanes, comprising a first phase and a second phase in the emulsion and further comprising the following components: A) polyols; B) blowing agent; C) surfactants; and D) isocyanates, wherein the isocyanate-reactive compounds A) are present in the first phase of the emulsion and the blowing agent B) is present in the second phase. The blowing agent B) is present in the near-critical or supercritical state and the isocyanate D) is present in the second phase in a proportion of ?10% by weight of the total amount of isocyanate D) in the composition. The invention further relates to a method of producing polyurethane foams by providing such a reaction mixture, wherein a polymerization takes place at the freshly formed interface between the polyol phase and the blowing agent phase, to the use of such a reaction mixture for producing polyurethane foams and also to the polyurethane foams obtained.

Abstract: The invention relates to a vacuum insulation panel comprising a barrier film and a core material having a density in the range from 50 to 350 kg/m3, wherein the core material comprises a mixture of A) from 30 to 100 percent by weight of nanoporous polymer particles which have a cell count in the range from 1000 to 100 000 cells/mm, where at least 60 percent by weight of the nanoporous polymer particles have a particle size of less than 100 ?m in the sieve analysis in accordance with DIN 66165, and B) from 0 to 70 percent by weight of pyrogenic or precipitated silica, and also a process for the production thereof.

Abstract: The present invention relates to a process for producing a polyurethane foam, where the blowing agent used is present in the supercritical or near-critical state. A reaction mixture is introduced into a closed mould, where the closed mould has been set up in such a way that its interior volume and/or the pressure prevailing in its interior can be altered after the introduction of the mixture by external influence. Through the selection of the surfactant it is possible to obtain microemulsions of the blowing agent in the polyol phase. The invention further relates to a nanocellular polyurethane foam obtainable by the process of the invention.

Abstract: A process for producing a polyurethane foam with bimodal cell size distribution, comprising the following steps: providing a mixture in a mixing head, where the mixture comprises: A) a component reactive towards isocyanates; B) a surfactant component; C) a blowing agent component selected from the group consisting of linear, branched or cyclic C1- to C6-alkanes, linear, branched or cyclic C1- to C6-fluoroalkanes, N2, O2, argon and/or CO2, where blowing agent component C) is present in the supercritical or near-critical state; D) a polyisocyanate component; discharging the mixture comprising components A), B), C), and D) from the mixing head where, during the discharge of the mixture, the pressure prevailing in the mixture is lowered to atmospheric pressure.