Abstract: A polyurethane foam, polyisocyanurate foam or polyurea foam is obtainable from the reaction of a mixture comprising A) a compound reactive towards isocyanate (“NCO-reactive compound”); B) a blowing agent selected from the group comprising linear, branched or cyclic C1 to C6 hydrocarbons, linear,branched or cyclic C1 to C6 fluorocarbons, N2, O2, argon and/or CO2, where the blowing agent B) is present in the supercritical or near-critical state; C) a polyisocyanate; D) an amphiphilic isocyanate; and E) optionally a surfactant and F) optionally other auxiliaries and additives. The invention further relates to the production of this polyurethane foam, where the blowing agent is emulsified in the isocyanate component containing amphiphilic isocyanate.

Abstract: The invention relates to a method for producing a polyurethane foam, wherein a mixture having the following is discharged from a mixing head through a discharge line: A) a component reactive toward isocyanates; B) a surfactant component; C) a blowing agent component selected from the group comprising linear, branched, or cyclic C1 to C6 hydrocarbons, linear, branched, or cyclic C1 to C6 fluorocarbons, N2, O2, argon, and/or CO2, wherein the blowing agent C) is present in the supercritical or near-critical state; and D) a polyisocyanate component. The component A) has a hydroxyl value=100 mg KOH/g and =1000 mg KOH/g. The blowing agent component C) is present at least partially in the form of an emulsion, and means provided with an opening or several openings are arranged in the discharge line in order to increase the flow resistance during the discharge of the mixture comprising A), B), C), and D), wherein the cross-sectional area of the opening or the sum of the cross-sectional areas of all openings is =0.

Abstract: A polyurethane foam, polyisocyanurate foam or polyurea foam is obtainable from the reaction of a mixture comprising A) a compound reactive towards isocyanate (“NCO-reactive compound”); B) a blowing agent selected from the group comprising linear, branched or cyclic C1 to C6 hydrocarbons, linear,branched or cyclic C1 to C6 fluorocarbons, N2, O2, argon and/or CO2, where the blowing agent B) is present in the supercritical or near-critical state; C) a polyisocyanate; D) an amphiphilic isocyanate; and E) optionally a surfactant and F) optionally other auxiliaries and additives. The invention further relates to the production of this polyurethane foam, where the blowing agent is emulsified in the isocyanate component containing amphiphilic isocyanate.

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 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: The invention relates to a reaction system for producing PUR and PIR hard foam materials, comprising the following components: A) a compound which is reactive towards isocyanates; B1) a surfactant component; C) a propellant in a supercritical or near-critical state; D) a polyisocyanate; and E) a layer silicate. The invention further relates to a reaction system for producing PUR and PIR hard foam materials, comprising the following components: B2) a surfactant component with functional groups which are reactive towards isocyanates; C) a propellant in a supercritical or near-critical state; D) a polyisocyanate; and E) a layer silicate. The invention further relates to a method for producing PUR and PIR hard foam materials and to PUR and PIR hard foam materials which can be obtained from the aforementioned reaction systems.

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 invention relates to a method for producing a polyurethane foam, wherein a mixture having the following is discharged from a mixing head through a discharge line: A) a component reactive toward isocyanates; B) a surfactant component; C) a blowing agent component selected from the group comprising linear, branched, or cyclic C1 to C6 hydrocarbons, linear, branched, or cyclic C1 to C6 fluorocarbons, N2, O2, argon, and/or CO2, wherein the blowing agent C) is present in the supercritical or near-critical state; and D) a polyisocyanate component. The component A) has a hydroxyl value=100 mg KOH/g and =1000 mg KOH/g. The blowing agent component C) is present at least partially in the form of an emulsion, and means provided with an opening or several openings are arranged in the discharge line in order to increase the flow resistance during the discharge of the mixture comprising A), B), C), and D), wherein the cross-sectional area of the opening or the sum of the cross-sectional areas of all openings is =0.

Abstract: A polyurethane foam is obtainable from the reaction of a mixture comprising A) an isocyanate-reactive compound; B) a blowing agent selected from the group comprising linear, branched or cyclic C1-C6 hydrocarbons, linear, branched or cyclic C1-C6 (hydro)fluorocarbons, N2, O2, argon and/or CO2, wherein said blowing agent B) is in the supercritical or near-critical state; and C) a polyisocyanate. The isocyanate-reactive compound A) comprises a hydrophobic portion and a hydrophilic portion and has an average hydroxyl functionality of more than 1. The hydrophobic portion comprises a saturated or unsaturated hydrocarbonaceous chain having 6 or more carbon atoms and the hydrophilic portion comprises alkylene oxide units and/or ester units. Component A) is very preferably a sorbutan ester of the formula (II): where w+x+y+z=20.

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 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: The present invention concerns a method for the treatment of polyurethane foam, wherein the polyurethane foam is obtainable from a reaction mixture comprising an ethylene oxide/propylene oxide polyol component with an OH number of ?20 mg KOH/g to ?45 mg KOH/g and an isocyanate component with an NCO content of ?20 weight-% to ?49 weight-% which is selected from the group comprising diphenylmethane diisocyanate, toluene diisocyanate, their prepolymers with an ethylene oxide/propylene oxide polyol whose OH number is from ?20 mg KOH/g to ?45 mg KOH/g and/or their allophanates, ureas, biurets, uretdiones, isocyanurates or carbodiimides. The invention further concerns a polyurethane foam which has been treated by such a method. After the foam formation has finished, the polyurethane foam is irradiated with microwave radiation and the irradiated energy, in relation to the volume accessible by the microwave radiation, is from ?1.0 kilojoules/liter to ?2.23 kilojoules/liter.

Abstract: The present invention relates to an improved process for the preparation of NCO-reactive components from fully reacted products of the isocyanate polyaddition process, in particular those based on MDI and/or TDI, using reactive solvents in a microwave field.

Abstract: The present invention relates to a process for the preparation of carbodiimide- and/or uretonimine-modified polyisocyanates by means of microwave radiation and to the use of such polyisocyanates for the synthesis of foamed and non-foamed polyurethane materials.

Abstract: The invention relates to door elements with radiation protection additive-containing polyurethane foams as a filling material for radiation protection, and to processes for their manufacture.

Abstract: An NCO-terminated prepolymer is produced by reacting a solid halogenated diol and a polyisocyanate. This prepolymer is useful in the production of flame-retardant polyurethanes.

Abstract: The present invention is directed to an agitator-free mixing head and a method for agitator-free production of a reaction mixture from an isocyanate and a higher-viscous polyol formulation, wherein both constituents are fed to a mixing zone and mixed with each other therein, whereby a polyol formulation with a viscosity of at least 3000 mPa.s is fed at low pressure into the mixing zone and at least two flows of low-viscosity constituents (isocyanate and optionally low-viscous polyol) are injected into the flow of high-viscous polyol formulation at high pressure.