Abstract: A process for treating polyether polyols prepared in a conventional manner by base-catalyzed reaction of H-functional initiator substances with alkylene oxides comprises a combination of a thermal-reactive step at a pH of less than 7 and a temperature above 60° C. and a thermal-distillative step in a countercurrent column using a purifying agent. The polyether polyols prepared according to the invention are used for producing low-fogging and low-odor PUR foams.

Abstract: An isocyanate-based rigid foam comprising the reaction product of an organic and/or modified organic polyisocyanate, a resin blend and, optionally, a relatively low molecular weight chain extender or crosslinker in the presence of a catalyst, and, optionally, further auxiliaries and/or additives, wherein the resin blend comprises a phthalic anhydride-initiated polyester polyol, a blowing agent comprising a C4-C6 hydrocarbon, and a fatty acid or fatty alcohol ethoxylate compatibilizing agent. The blowing agent is soluble in the polyol composition, thereby reducing the risks associated with such blowing agents in processes for making rigid polymer foam articles and providing rigid foams having good dimensional stability and improved insulation properties.

Abstract: Mixtures of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates (raw MDI) having a reduced iodine color number and a reduced chlorine content are prepared by reacting the corresponding mixtures of diphenylmethanediamines and polyphenylpolymethylenepolyamines with phosgene in the presence of at least one inert organic solvent at elevated temperature, and then, after phosgenation is complete, incorporating into the reaction mixture, in the presence or absence of the phosgene, a mixture of water and at least one monohydric or polyhydric polyoxyalkylene alcohol, preferably having a functionality of from 2 to 3, and advantageously having a hydroxyl number of from 20 to 1800, in an effective amount which advantageously comprises from more than 0.01 to 0.3% by weight of water (i) and from 0.

Abstract: Flexible foams based on polyisocyanate polyaddition products are produced by reacting polyisocyanates with compounds which are reactive toward isocyanates in the presence of catalysts, blowing agents and, if desired, flame retardants, auxiliaries and/or additives, wherein polyether polyalcohols (c) which are obtainable by addition of alkylene oxides onto substances containing active hydrogens are used as substances which are reactive toward isocyanates, where, in a first stage, at least one substance (a) containing 2 or 3 active hydrogens is reacted with at least one alkylene oxide in the presence or absence of catalysts, subsequently at least one substance (b) which contains at least four active hydrogens and, if desired, further catalyst is added to the reaction mixture from the first stage and this mixture is then reacted in a second stage with at least one alkylene oxide.

Abstract: It has been found that non-chlorinated pentafluoropropane blowing agents may be used alone or in combination with water in flexible integral skin foams. For example, foams prepared from a resin blend incorporating 1,1,1,3,3-pentafluoropropane (HFA-245fa) alone or in combination with water exhibit physical characteristics such as resistance to abrasion and cracking on flex comparable to conventional chlorinated fluorocarbon blown foams. Such foams made using the resin blend of the present invention are suitable for use in many applications including, for example, shoe soles.

Abstract: Compact, transparent polyisocyanate polyaddition products are produced in a process by reacting (a) isocyanates with (b) compounds reactive to isocyanates, if desired in the presence of (c) catalysts and (d) auxiliaries and/or additives, which comprises using as (b) compounds reactive to isocyanates a mixture (i) which has an average functionality of >3 and an average hydroxyl number of from 300 to 950 mg KOH/g.

Abstract: The present invention discloses a method for the formation of and a flexible slabstock polyurethane foam having substantially improved indentation force deflection and resilience characteristics while maintaining the other physical properties. The method comprises the steps of: forming a polyol blend having a nominal functionality of at least 2.3 by combining at least one polyether polyol having a plurality of terminal ethylene oxide caps of from 5 to 25% by weight based on the total weight of the polyether polyol, a molecular weight of greater than or equal to 4000 Daltons, and an unsaturation of greater than 0.04 meq/g KOH; at least one graft polyether polyol having an equivalent weight of greater than 1000 Daltons, a solids content of at least 28%, and a plurality of terminal ethylene oxide caps of from 5 to 25% by weight based on the total weight of the graft polyether polyol; and at least one very low unsaturated polyether polyol having an unsaturation of less than or equal to 0.

Abstract: A process for producing pipes illustrated with foams comprises [a] providing, between an inner carrier pipe and an outer pipe arranged parallel thereto, a holder which is provided with at least one aperture and is mounted so that it can be moved axially and positions the carrier pipe in the outer pipe and [b] introducing into the vacant space between the two pipes, via the aperture (s) in the holder, a mixture for the preparation of foams, where [b1)] during the introduction of the mixture, the holder moves in an axial direction with respect to the outer pipe and the carrier pipe, then [c] after the mixture is charged, it is reacted to give the foam and [d)] the holder and, if desired, the outer pipe are removed.

Abstract: Compact and preferably cellular polyurethane elastomers are prepared by reacting a) relatively high molecular weight polyhydroxyl compounds and if desired, b) low molecular weight chain extenders and/or crosslinkers with c) phenylene 1,4-diisocyanate (p-PDI) and at least one additional aromatic diisocyanate selected from the group consisting of tolylene diisocyanate, diphenylmethane diisocyanate, 3,3′-dimethylbiphenyl diisocyanate, 1,2-diphenylethane diisocyanate and/or aliphatic diisocyanate, having from 4 to 12 carbon atoms and/or cycloaliphatic diisocyanate having from 6 to 18 carbon atoms, where the formative components (a), (c) and, if used, (b) are advantageously reacted by the prepolymer method, in the presence or absence of d) catalysts, e) blowing agents and f) additives. Isocyanate prepolymers suitable for this purpose are described.

Abstract: A process for the preparation of foamed plastics materials based on polyisocyanate polyaddition products by the reaction of isocyanates with isocyanate-reactive compounds in the presence of catalysts and, optionally, auxiliaries and/or additives, wherein i) isocyanates having isocyanurate and/or biuret structures are used, the isocyanate-reactive compounds used are ii) at least one diol and/or polyol having a molecular weight of from 400 to 8000 and containing at least 50% of primary hydroxyl groups based on all of the hydroxyl groups present in the compound, iii) at least one compound having at least one primary amine group, and diols and/or triols having molecular weights of less than 400 are optionally used as chain-extending and/or crosslinking agents, the reaction being carried out in the presence of iv) at least one tertiary amine acting as catalyst and/or v) at least one metal salt acting as catalyst and vi) water.

Abstract: Two-component polyurethane systems composed of an at least bifunctional polyisocyanate component and a polyol component have a polyol component which comprises at least one hydroxyl-containing cyclic acetal and/or ketal.

Abstract: The present invention relates to graft polyols employing a t-amyl peroxy compound as free radical initiator. The novel graft polyols are made by polymerizing at least one monomer in a polyol composition in the presence of a free radical initiator and preferably a chain transfer agent. The resulting graft polyols are in turn useful in reactions with polyisocyanates to make polyurethane products.

Abstract: In a process for producing self-releasing, compact or cellular moldings which comprise polyisocyanate polyaddition products and may contain reinforcing material by reacting a) organic and/or modified organic polyisocyanates with b) at least one compound containing at least two reactive hydrogen atoms and having a molecular weight of from 62 to 10,000 and, if desired, c) chain extenders and/or crosslinkers in the presence of d) internal mold release agents and in the presence of or absence of e) catalysts, f) blowing agents, g) reinforcing materials and h) auxiliaries in an open or closed mold, the internal mold release agents (d) used are diesters and/or monoesters of alkylsuccinic acids and/or diesters and/or monoesters of alkenylsuccinic acids.

Abstract: In a process for preparing amines, in which at least one compound containing at least one nitro group is reacted with hydrogen in the presence of a supported catalyst comprising, as catalytically active metal, nickel, if desired together with at least one metal of transition group I, V, VI and/or VIII, the reduced and stabilized supported catalyst comprises nickel crystallites having a bimodal nickel crystallite size distribution having maxima at 30-80 Angstrom and 81-150 Angstrom on a support comprising ZrO.sub.2, ZrO.sub.2 --HfO.sub.2 and/or SiO.sub.2 --ZrO.sub.2 and/or SiO.sub.2 --ZrO.sub.2 --HfO.sub.2 and in the reduced and passivated state has a nickel content of 60-80 percent by mass, an SiO.sub.2 content of 0-20 percent by mass, a ZrO.sub.2 content of 0-40 percent by mass, an HfO.sub.2 content of 0-4 percent by mass and after further reduction for one hour at 100.degree. C. has a degree of reduction of at least 70%.

Abstract: The present invention provides a liquid methylene bis(phenylisocyanate) composition including a high concentration of methylene bis(phenylisocyanate) which has an improved storage stability. The invention further provides a method of making the liquid methylene bis(phenylisocyanate) compositions of the present invention.

Abstract: In a process for producing polyurethane foams, preferably semirigid polyurethane foams and flexible, semirigid and rigid polyurethane integral foams,a) at least one modified or unmodified organic polyisocyanate is reacted withb) at least one relatively high molecular weight compound containing at least two reactive hydrogens and, if desired,c) low molecular weight chain extenders and/or crosslinkers in the presence ofd) blowing agents, preferably water and/or (cyclo)alkanes,e) a catalyst mixture comprising, according to the invention,e') from 35 to 65 parts by weight of di-n-octyltin bis(2-ethylhexyl thioglycolate) ande") from 65 to 35 parts by weight of mono-n-octyltin tris(2-ethylhexyl thioglycolate) and also, if desired,e'") cocatalysts selected from the group of tertiary amines, alkali metal and alkaline earth metal salts of monocarboxylic acids having from 1 to 20 carbon atoms andf) if desired, additives,with the reaction for forming the polyurethane integral foams being carried out in a closed mold with

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: There is provided an sealant made with an isocyanate or hydroxyl terminated prepolymer made by reacting a stoichiometric excess of an organic polyisocyanate with polyols made of at least a polyoxyalkylene polyether triol or a mixture thereof with a polyoxyalkylene polyether diol. The triol or diol has within its structure the nucleus of an initiator compound, an internal blocks of oxypropylene groups, and external blocks of oxyalkylene groups, wherein the internal blocks of oxypropylene are between said nucleus and said external blocks, said external blocks are made of oxyalkylene groups derived from a C.sub.4 or higher alkylene oxide. The amount of the internal blocks of oxypropylene groups is from 25 weight percent to 80 weight percent based on the weight of all oxyalkylene groups and initiator in the prepolymer The triol or diol has a compatibility index of 25.degree. C. or less, and may be part of a two component or a one component moisture cured sealant.

Abstract: The present invention relates to energy absorbing elastomers having a resilience of no more than 20.0% according to ASTM D2632-92. The energy absorbing elastomers are hydrophobic in nature and have extended gel times thus making them suitable for high volume applications such as coating a large substrate or filling a large void between two substrates.

Abstract: Polyurethanes having improved curing are prepared by reactinga) organic and/or modified organic diisocyanates and/or polyisocyanates withb) polyether polyols based on aromatic amines, able to be prepared by reacting specific amine combinations and, if desired, further coinitiators in a stage wise molecular addition of alkylene oxide, and also, if desired, further relatively high molecular weight compounds containing 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) further auxiliaries and/or additives,wherein the specific amine combination used is a mixture of amines of the diphenylmethane series consisting of from 5 to 20% by weight of 4-ring amine, from 15 to 30% by weight of 3-ring amine, from 20 to 35% by weight of amines having more than 4 rings and from 25 to 50% by weight of 2-ring amine, wherein the proportions add up to 100% by weight, in combination with further aromatic