摘要:
A first reaction mixture, prepared from (a) isocyanates with isocyanate contents of from 5 to 50% and (b) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "a" to component "b" of 0.8:1 to 5:1, from 0.1 to 20% of a blowing agent and, optionally, other known additives, is introduced into the rigid cavity of a closed mold. After this mixture has become resistant to permeation, but is still compressible, a second reaction mixture, either the same or different from the first reaction mixture, prepared from (c) isocyanates having isocyanate contents of from 5 to 50% and (d) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "c" to component "d" of from 0.8:1 to 5:1, specific internal mold release agents and optionally blowing agents and other additives, is introduced into the mold, such that it surrounds the first mixture and compresses it. A third, optional, reaction mixture, the same as or different from the second mixture, may also be employed in a manner similar to the introduction of the second mixture. The final composite plastic part releases smoothly from the mold.
摘要:
A first reaction mixture, prepared from (a) aromatic isocyanates with isocyanate contents of from 5 to 50%, and (b) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "a" to component "b" of 0.8:1 to 5:1, from 0.1 to 20% of a blowing agent and, optionally, other known additives, is introduced into a closed mold with a rigid cavity. After this mixture has become resistant to permeation, but is still compressible, a second reaction mixture, prepared from (c) aliphatic and/or cycloaliphatic polyisocyanates having isocyanate contents of from 5 to 50% and (d) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "c" to component "d" of from 0.8:1 to 5:1, an internal mold release agent and optionally blowing agents and other additives, is introduced into the mold, such that the second mixture surrounds the first mixture and compresses it. A third, optional, reaction mixture, the same as or different from the second mixture, may also be employed in a manner similar to the introduction of the second mixture. The final composite plastic part releases smoothly from the mold and evidences good lightfast and colorfast properties.
摘要:
A homogeneous, storage-stable, emulsifier-free polyol mixture having a high mixed OH-number and a high ethylene glycol content comprising 100 parts of a relatively high molecular weight polyalkylene oxide polyol having an OH-number of from 20 to 210, which contains at least 5%, and less than 80%, by weight, of terminal ethylene oxide blocks, from 0.1 to 30 parts of a low molecular weight diol mixture having an OH-- number of 1200 to 1650 in the form of a reaction product of 1 mole of ethylene glycol with 0.1 to 0.5 moles of propylene oxide, optionally, up to 5 parts of di- and/or tri-functional compounds containing reactive hydrogen atoms and having a molecular weight of from 32 to 399, and optionally, other auxiliaries and additives known in the production of polyurethanes. Also, polyurethanes produced using these polyol mixtures.
摘要:
A homogeneous, storage-stable, emulsifier-free polyol mixture having a high mixed OH-number and a high ethylene glycol content comprising 100 parts of a relatively high molecular weight polyalkylene oxide polyol having an OH-number of from 20 to 210, which contains at least 5%, and less than 80%, by weight, of terminal ethylene oxide blocks, from 0.1 to 30 parts of a low molecular weight diol mixture having an OH-number of 1200 to 1650 in the form of a reaction product of 1 mole of ethylene glycol with 0.1 to 0.5 moles of propylene oxide, optionally, up to 5 parts of di- and/or tri-functional compounds containing reactive hydrogen atoms and having a molecular weight of from 32 to 399, and optionally, other auxiliaries and additives known in the production of polyurethanes. Also, polyurethanes produced using these polyol mixtures.
摘要:
A single-phase, storage-stable, emulsifier-free polyol mixture comprising 100 parts of a relatively high molecular weight polyoxyalkylene polyol of OH number from 20 to 120, which has at least 5% and less than 80% by weight, of terminal oxyethylene blocks; from 1 to 100 parts of a low molecular weight diol mixture which is a reaction product of ethylene glycol, butane diol-1,4, or a mixture of ethylene glycol and butane diol-1,4, with from 0.05 to 0.50 mols of alkyl oxiranes; from 0.1 to 5 parts of solubilizing additives comprising one or more salts, the cations of which are from Groups I, II and III of the Periodic Table, ammonium or mono- to tetra-alkyl ammonium ions, and the anions of which are produced by removing at least one proton from an acid having a K.sub.s value of at least 10.sup.-7 ; and, optionally, other compounds having isocyanate-reactive hydrogen atoms and other auxiliaries and additives for polyurethane production. Also polyurethanes produced using these polyol mixtures.
摘要:
The instant invention relates to an improved process for the continuous production of an aliphatic monoisocyanate from the corresponding N-alkyl carbamic acid aryl ester. More particularly, the invention is directed to a process for the continuous production of monoisocyanates corresponding to the formulaR--NCOin whichR represents an aliphatic hydrocarbon radical containing 1 to 3 carbon atoms comprising thermally decomposing the corresponding N-alkylcarbamic acid aryl esters corresponding to the formulaR--NH--CO--O--R'in whichR has the meaning above andR' represents a radical of the type obtained by removing the hydroxyl group from a monophenol having a boiling point below 250.degree. C. at normal pressure, and separating the decomposition products by decomposition, further characterized in that(a) a solution of the N-alkylcarbamic acid aryl ester in an organic solvent, which solvent is inert under the reaction conditions and has a boiling point lying at least 20.degree. C. above the boiling point of the monoisocyanate to be formed, is heated to a temperature of from 160.degree. C. to 250.degree. C. at normal pressure or at slightly reduced pressure within the range of 200 to 1013 mbar, thereby resulting in the decomposition of the ester into the corresponding monoisocyanate and the corresponding phenol, as well as the evaporation of the solvent and the decomposition products, and(b) the vapors formed are fed into a distillation column with the monoisocyanate obtained at the head of the column and with the phenol and at least a major portion of the solvent obtained from a side stream or from several side streams.
摘要:
Molded polyurea foam parts having densities of from 200 to 600 kg/m.sup.3 and a compact skin are made by reacting a polyisocyanate component with a polyamine component in a closed mold at an isocyanate index of from 70 to 130. The polyamine component generally includes (1) an aminopolyether having a molecular weight of from 1800 to 12,000 and 2 to 3 isocyanate reactive groups of which at least 90% are aromatically bound primary and/or secondary amino groups, (2) an aromatic diamine, (3) a foaming agent and optionally (4) known auxiliaries and additives. The polyisocyanate component includes any aromatic di- and/or poly-isocyanate. Parts produced by this process have excellent mechanical properties and a well-defined solid skin.
摘要翻译:通过使多异氰酸酯组分与多胺组分在封闭模具中以70至130的异氰酸酯指数反应制备密度为200至600kg / m 3的模制聚脲泡沫部件和紧密表皮。多胺组分通常包括(1 )分子量为1800〜12,000的氨基聚醚和2〜3个异氰酸酯反应性基团,其中至少90%是芳族结合的伯和/或仲氨基,(2)芳族二胺,(3)发泡剂和 (4)已知的助剂和添加剂。 多异氰酸酯组分包括任何芳族二 - 和/或多异氰酸酯。 通过该方法生产的部件具有优异的机械性能和明确的固体皮肤。
摘要:
The instant invention is directed to a process for the production of elastic polyurethane foams capable of being flame laminated and high frequency welded, comprising reacting(a) polyisocyanates with(b) polyethers having a molecular weight of from 400 to 10,000 and having at least two hydroxyl groups and(c) hydroxy-pivalic acid neopentylglycol ester of the formula: ##STR1## used in a quantity of from 1 to 20% by weight, based on the hydroxyl polyether, in the presence of a blowing agent.The instant invention is also directed to the polyurethane foams prepared thereby.
摘要:
This invention relates to a new process for the production of organic polyisocyanates containing polyuret groups, to polyisocyanates obtainable by this process and to the use of the products obtained by the process as an isocyanate component in the production of polyurethane plastics.
摘要:
The present invention is directed to a process for the production of polyurea-based microcellular moldings comprising reacting(a) at least one diisocyanate or polyisocyanate containing only aromatically bound isocyanate groups,(b) at least one compound containing at least two isocyanate-reactive groups, and(c) optionally the auxiliaries and additives known in polyurethane chemistry, in closed molds, components (a)-(c) being processed as a one-shot system by reaction injection molding, characterized in that component (b) comprises at least one polyether compound (b1) optionally in admixture with other isocyanate-reactive compounds and containing at least 3 aliphatically bonded ether groups and n-aliphatically bonded isocyanate-reactive groups, n standing for an integer or, statistically a fraction of from 2-4(i) at least (100:n) % of the isocyanate-reactive groups present in component (b1) being aliphatically bonded primary and/or secondary amino groups,(ii) at least 10 equivalent % of said amino groups being present in the form of ammonium carbamate groups having a functionality of two in the isocyanate addition reaction, of the type obtained by reacting aliphatically bonded, primary or secondary amino groups with carbon dioxide,(iii) the unmodified compounds containing at least 3 ether groups having a molecular weight of from 200 to 10,000 and(iv) at least 0,2 equivalent % of all isocyanate-reactive groups of the total component (b) being ammonium carbamate groups.The present invention also relates to said compounds (b) optionally in admixture with the auxiliaries and additives known in polyurethane chemistry.