摘要:
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 =0.1% and =99.9% of the inner cross-sectional area of the discharge line.
摘要:
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 =0.1% and =99.9% of the inner cross-sectional area of the discharge line.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要翻译:聚氨酯泡沫可以由包含A)异氰酸酯反应性化合物的混合物的反应获得; B)选自直链,支链或环状C 1 -C 6烃,直链,支链或环状C 1 -C 6(氢)氟碳,N 2,O 2,氩和/或CO 2的发泡剂,其中所述发泡剂B)为 处于超临界或近临界状态; 和C)多异氰酸酯。 异氰酸酯反应性化合物A)包含疏水部分和亲水部分,并且具有大于1的平均羟基官能度。疏水部分包含具有6个或更多个碳原子的饱和或不饱和烃链,亲水部分包括环氧烷单元 和/或酯单元。 组分A)非常优选是式(II)的sorbutan酯:其中w + x + y + z = 20。
摘要:
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.