Abstract: The present invention relates generally to polyisocyanate compositions for use in polyurethane thermoformable foams. The polyisocyanate compositions of the present invention which are also useful as binder/hardeners for prefoamed products offer improved stability at relatively low temperatures over other known polymeric diphenylmethane diisocyanate compositions.

Abstract: The present invention relates to a process for the preparation of CFC-free, flexible polyurethane (molded) foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups having a content of NCO groups of from 22 to 30% by weight which are themselves prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates having a content of diphenylmethane diisocyanate isomers of from 55 to 99% by weight, based on the total weight, with at least one trifunctional polyoxypropylene-polyol having a hydroxyl number of from 20 to 60, withB) relatively high-molecular-weight polyhydroxyl compounds and, if desired,C) low-molecular-weight chain extenders and/or crosslinking agents,in the presence ofD) blowing agents,E) catalysts and, if desired,F) auxiliaries and/or additives,and to the polyisocyanate mixtures (A) modified by means of urethane groups which can be used according to the invention.

Abstract: A homogeneous, demixing-stable polyol component comprising at least two relatively high molecular weight compounds containing at least two reactive hydrogen atoms and, if desired, low molecular weight chain extenders and/or crosslinkers and also, if desired, blowing agents, catalysts and further auxiliaries and/or additives is prepared by adding at least one amine and at least one organic and/or modified organic isocyanate to this component.This polyol component is useful for producing polyurethanes, in particular compact and foamed polyurethanes.

Abstract: A phase-stable polyol component comprisesA1) at least one polyether polyalcohol and/or polyether ester polyalcohol,A2) at least one polyester polyol andA3) at least one liquid flame retardant additive,where the constituents A1:A2:A3 are present in a weight ratio of 10.+-.4.5:13.+-.4:14.+-.4.5.

Abstract: The present invention relates to prepolymers, comprising(a) a polymethylene polyphenylene polyisocyanate; and(b) a polyether polyol having an average hydroxyl equivalent weight of at least about 700;wherein the resulting prepolymer has an average viscosity of between about 400 to about 2000 centipoise at 25.degree. C. The prepolymer is useful, for example, for the production of polyurethane foams and, more particularly, to medium density flexible foams having superior flow characteristic and fast demold times.

Abstract: Polyurethane foams are produced by reactinga) organic and/or modified organic diisocyanates and/or polyisocyanates withb) at least one relatively high molecular weight compound containing at least two reactive hydrogen atoms,c) at least one compound containing from three to eight, preferably from three to six, reactive hydrogen atoms andd) low molecular weight chain extenders and/or crosslinkers containing at least two reactive hydrogen atomsin the presence ofe) blowing agentsf) catalysts and, if desired,g) further auxiliaries and additives,wherein (c) are ethylene oxide-rich adducts having an ethylene oxide content of more than 50% by weight and an OH number of from 200 to 800 mg KOH/g and (d) are polyfunctional chain extenders and/or crosslinkers having an OH number of more than 700 mg KOH/g.The polyurethane foam produced by this process can be used as upholstery material.

Abstract: In a process for producing rigid polyurethane foams by reactinga) polyisocyanatesb) compounds containing at least two hydrogen atoms capable of reacting with isocyanate groups, in the presence ofc) catalysts,d) blowing agents and, if desired,e) further auxiliaries and/or additives,the component b) comprises at least one recycled polyol which is formed by glycolysis of polyurethanes.

Abstract: There is now provided a sealant and elastomer made with a polyol having an unsaturation level of 0.04 to 0.07, manufactured with a basic salt of an alkaline earth metal or a basic salt of cesium, such as cesium hydroxide. The elastomers and sealants made therefrom exhibit an increasing modulus of elasticity when strained from 100 percent elongation to 300 percent elongation. The reduced unsaturation polyols are simple and inexpensive to make while imparting good physical properties to the sealants and elastomers.

Abstract: This invention is a liquid polyisocyanate prepolymer comprising the reaction product of an organic polyisocyanate blend and a polyoxyalkylene polyol, where polyisocyanate blend isA) a diphenylmethane diisocyanate comprising from 50 weight percent to 95 weight percent 4,4'-diphenylmethane diisocyanate, from 5 weight percent to 50 weight percent 2,4'-diphenylmethane diisocyanate, and less than 10 weight percent 2,2'-diphenylmethane diisocyanate, said weight percentages based on the total weight of the ingredients in A);B) a polymethylene polyphenyl polyisocyanate comprising from 30 weight percent to 70 weight percent diphenylmethane diisocyanate, the remainder comprising polymethylene polyphenyl polyisocyanates having functionalities greater than two, said weight percentages based on the total weight of the ingredients in B);C) and optionally a uretonimine-carbodiimide modified diisocyanate comprising from 10 weight percent to 35 weight percent uretonimine-carbodiimide species, the remainder comprising essentia

Abstract: A process for recycling plastic waste containing a mixture of polyurethanes and other plastics, comprises reacting the plastic waste with an alcohol mixture comprising at least one low-molecular-weight, at least difunctional alcohol and at least one polyether-polyol, and then separating the resultant glycolysis polyol mechanically from the other plastic waste.

Abstract: A microcellular PU elastomer having improved dynamic-mechanical properties and based on an isocyanate component consisting essentially of 4,4'-MDI and also further customary constituents has, after heating at from 100 to 120.degree. C. for from 8 to 24 hours, a melting range of from 130.degree. C. as the minimum lower limit to 230.degree. C. as a minimum upper limit, measured by differential scanning calorimetry (DSC) at a heating rate of 20.degree. C./min, and a urea content of from 14 to 18% by weight.A process is also provided for preparing such a microcellular PU elastomer having improved dynamic mechanical properties. The microcellular PU elastomers can be used for producing damping elements.

Abstract: A process for preparing a homogeneous polyol component which is stable to separation and consists of at least one compound of relatively high molecular weight having at least two reactive hydrogen atoms and low-molecular-weight chain extenders and/or crosslinkers and, if desired, of blowing agents, catalysts and other auxiliaries and/or additives comprises the addition to this component of at least one amine and at least one organic and/or modified organic isocyanate; the invention also provides the corresponding polyol component which is stable to separation.The use of this polyol component for preparing PUR, in particular compact or foamed PUR, is also described.

Abstract: A stable dispersion of melamine in polyol components comprising at least one relatively high molecular weight compound containing at least two reactive hydrogen atoms and, if desired, low molecular weight chain extenders and/or crosslinkers, blowing agents, catalysts, flame retardants and also further auxiliaries and/or additives is prepared by using the melamine in combination with at least one amine and at least one organic and/or modified organic isocyanate.

Abstract: The invention relates to a process for the production of polyurethane foams by reactinga) at least one organic polyisocyanate withb) at least one polyalkylene-polyol (b1) having a hydroxyl number of from 30 to 500, obtainable by alkoxylation of at least one initiator molecule from the group consisting of N,N'-bis(3-aminopropyl)ethylenediamine, tripropylenetetramine and tetrapropylenepentamine using at least one alkylene oxide, preferably ethylene oxide and/or 1,2-propylene oxide, or mixtures of the polyoxyalkylene polyols (b1) and other polyhydroxyl compounds having a functionality of from 2 to 8 and a hydroxyl number of from 15 to 500, andc) if desired, chain extenders and/or crosslinking agents,in the presence ofd) blowing agents and, if desired,e) catalysts andf) additives,and to the novel polyoxyalkylene-polyols (b1) which can be used for this purpose.

Abstract: Rigid polyurethane foams having a low thermal conductivity are produced by reactinga) organic and/or modified organic polyisocyanates withb) at least one compound containing at least 2 reactive hydrogen atoms in the presence ofc) blowing agents,d) catalysts and, if desired,e) auxiliaries and/or additives,wherein graphite is added to the component a) and/or b).

Abstract: Thus, there is provided according to the present invention polyol compositions comprising(A) a polytetramethylene ether glycol, and(B) a trifunctional active hydrogen compound-initiated polyoxyalkylene polyether polyol having a degree of unsaturation of not greater than 0.04 milliequivalents per gram of said polyether polyol.

Abstract: A process for producing rigid polyurethane foams with reduced density by reactinga) organic and/or modified organic polyisocyanates withb) at least one higher-molecular-weight compound having at least two reactive hydrogen atoms and, if desired,c) low-molecular-weight chain extenders and/or crosslinkers in the presence ofd) blowing agents,e) catalysts and, if desired,f) other auxiliaries and/or additives,is described, which comprises using, as blowing agent (d), a mixture of cyclopentane with at least one compound which is homogeneously miscible with cyclopentane selected from the class consisting of the alkanes and/or alkenes having 3 or 4 carbon atoms in the molecule and with the carbon dioxide produced from water and isocyanate, and using, as higher-molecular-weight compound (b) having at least two reactive hydrogen atoms, polyethers which contain aromatics and nitrogen.The use of the rigid foams produced in this way as insulating material is also described.

Abstract: A microcellular PU elastomer having improved dynamic mechanical properties and based on an isocyanate component consisting essentially of 4,4'-MDI and further customary constituents has a physicochemical structure which, in the gel permeation chromatograph (GPC) of a solution of the microcellular polyurethane elastomer prepared at 90.degree. C. in N,N-dimethylformamide containing 1 percent of di-n-butylamine measured against polymethyl methacrylate (PMMA) as standard, displays a signal occurring in addition to low molecular weight main signal and comprising one or more peaks at an (apparent) molar mass of greater than 250,000 g/mol which becomes smaller or disappears on addition of lithium chloride to this solution, and a urea content of from 14 to 18% by weight.A process is also provided for preparing such a microcellular PU elastomer having improved dynamic mechanical properties. The microcellular PU elastomers can be used for producing damping elements.

Abstract: A stable dispersion of melamine in polyol components comprising at least one relatively high molecular weight compound containing at least two reactive hydrogen atoms and, if desired, low molecular weight chain extenders and/or crosslinkers, blowing agents, catalysts, flame retardants and also further auxiliaries and/or additives is prepared by using the melamine in combination with at least one amine and at least one organic and/or modified organic isocyanate. Such a dispersion can be used for producing flame-resistant polyurethane foams.

Abstract: In a process for producing foams based on polyisocyanate polyaddition products by reacting isocyanates with compounds which are reactive toward isocyanates and have a molecular weight of from 400 to 8000 in the presence of blowing agents, catalysts and, if desired, chain extenders and/or crosslinkers having a molecular weight of <400, auxiliaries and/or additives, use is made of isocyanates having isocyanurate and/or biuret structures, at least one compound which is reactive toward isocyanates, has a molecular weight of from 400 to 8000 and contains at least 50% primary hydroxyl groups, as catalysts at least one tertiary amine and at least one metal salt plus from 0.5 to 5.3% by weight of water, based on the weight of the compounds which are reactive toward isocyanates and have a molecular weight of from 400 to 8000, and the reaction is carried out at >40.degree. C.