Abstract: According to the present invention, relatively high molecular weight aliphatic and/or aromatic polyamines having molecular weights of from 400 to 8,000 (preferably from 600 to 4,000) are mixed with substantially equivalent quantities of low molecular weight, solid, finely-divided diisocyanates having a melting point of >40.degree. C., (preferably >80.degree. C.), such as phenylene diisocyanate, naphth lene-1,5-diisocyanate, dimeric toluylene-2,4-diisocyanate or the urea diisocyanate of toluylene-2,4-diisocyanate. This mixture, having a pot life of at least several minutes, is subsequently heated to a relatively high temperature, such as from 80.degree. to 200.degree. C.The products obtained have excellent elastic properties over a broad temperature range. They have an exceptionally flat modulus of elasticity curve (G') in the torsional vibration test. The hard and soft segments are markedly segregated and are thus not substantially disturbed by reciprocal interaction causing "softening".

Abstract: A process for producing storage-stable solutions of pyrocarbonic acid dialkyl esters in organic liquids inert to these esters comprising adding certain carbonyl compounds, sulfonyl compounds and/or thiourea to these pyrocarbonic acid dialkyl ester solutions. Also the use of these carbonyl compounds, sulfonyl compounds and/or thiourea for producing stabilized polyisocyanate preparations suitable for the production of polyurethane foams.

Abstract: The present invention relates to a process for the production of solid polyisocyanates of retarded reactivity stabilized by surface modification by reacting solid, finely divided polyisocyanates, and particularly dimeric tolylene diisocyanate, dimeric diphenylmethane diisocyanate and 3,3'-diisocyanato-4,4'-dimethyl-N,N'-diphenyl urea, with acyclic, mono- or bicyclic compounds having an amidine or guanidine structure and which do not contain any hydrogen atoms reactive to isocyanates at room temperature in a quantity of from 0.1 to 25 equivalent percent of "amidine" or "guanidine" per isocyanate equivalent. The reaction may be carried out directly in a liquid medium selected from the group consisting of active hydrogen compounds, plasticizers, water, and solvents to form a suspension of polyadduct-coated, stabilized polyisocyanates in the liquid medium.

Abstract: Low molecular weight 4,4'-diphenylmethane-uretdione-diisocyanates corresponding to the formula: ##STR1## wherein n is a number from 0 to 1,are made by dimerizing diphenylmethane-4,4'-diisocyanate at a temperature of 50.degree. C. or less in a mixture of non-polar and moderately polar solvents in the presence of a dimerization catalyst. The dimerization product may then be worked up at low temperatures (i.e., .ltoreq.50.degree. C.). The dimerization products of diphenylmethane-diisocyanate thus obtained generally have only a small amount of oligomeric uretdione-diisocyanates present. These dimerization products may be used advantageously in the synthesis of polyurethanes.

Abstract: Aromatic uret dione diurea diamines corresponding to the formula ##STR1## in which X, Y, m and n are as defined herein are produced by reacting an aromatic diamine with a diisocyanate corresponding to a specified formula in a molar ratio of diamine to diisocyanate of at least 1.8 to 1. These diamines are particularly useful in the production of elastomers.

Abstract: A process for the production of an optionally cellular polyurethane by reacting at least one compound having at least two hydrogen atoms which are reactive with isocyanate groups and have a molecular weight of from about 400 to 10,000 with polyisocyanates in the presence of a poly(dialkylaminoalkyl)ether catalyst corresponding to the formula ##STR1## wherein A represents a straight-chain or branched-chain (x+1)-valent, optionally substituted C.sub.2 -C.sub.6 alkyl radical,x represents an integer of 1 to 4 andR.sup.1 -R.sup.4 represent the same or different C.sub.1 -C.sub.4 alkyl radicals, which optionally form a heterocyclic radical with N.

Abstract: Diisocyanates corresponding to the formula ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 (an isocyanate-containing radical) are as defined herein are made by several processes. These diisocyanates may be made by phosgenating the diamine in which the diisocyanate is based. They may also be produced by treating the bis-urethane of the tertiary alcohol corresponding to the diisocyanate with phosgene. Such diisocyanates may also be made by treating a specific type of bis-urea with hydrogen chloride. The diisocyanates corresponding to the above-given formula are particularly useful in the production of polyurethanes having good flame-proof and mechanical properties.

Abstract: A process for the production of solid polyisocyanates stabilized by a polymer coating and showing retarded reactivity comprising reacting(1) one or more solid polyisocyanates in particulate form, said polyisocyanates having melting points above 30.degree. C., and(2) from 0.1 to 25 equivalent percent of amine per isocyanate equivalent of an organic compound having a molecular weight of from 32 to 6000, said organic compound being selected from the group consisting of(a) di- or higher functional compounds containing 2 or more aliphatically-bound primary and/or secondary amino groups,(b) compounds containing one or more terminal --CO--, --NH--, --NH.sub.

Abstract: Optionally-foamed polyurethanes are produced by reacting polyisocyanates with organic compounds containing at least two isocyanate-reactive hydrogen atoms and having a molecular weight in the range from 400 to 10,000, in the presence of activators corresponding to the general formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 may be the same or different and represent C.sub.1 -C.sub.20 -alkyl, C.sub.5 -C.sub.7 -cycloalkyl, C.sub.6 -C.sub.14 -aryl or C.sub.7 -C.sub.30 -alkaryl,X.sup.1 and X.sup.2 may be the same or different and represent halogen or a radical of the formula --OR.sup.5, --SR.sup.6 or ##STR2## with the proviso that X.sup.1 and X.sup.2 cannot both represent a halogen atom,R.sup.5, R.sup.6 and R.sup.7 may be the same or different and represent a C.sub.1 -C.sub.20 -alkyl, C.sub.5 -C.sub.7 -cycloalkyl, C.sub.6 -C.sub.14 -aryl or C.sub.7 -C.sub.30 -alkaryl and 1.ltoreq.x.ltoreq.

Abstract: This invention relates to a process for the production of polyurethanes, particularly polyurethane foam moldings having a compact skin and a cellular core, using special tin activators.

Abstract: Compounds having both s-triazine units and epoxide groups present are prepared by reacting an epoxide containing an isocyanate-reactive group with a triisocyanate corresponding to the formula: ##STR1## in which X is as defined herein. These reactants are used in quantities such that the equivalent ratio of isocyanate groups to isocyanate-reactive groups is maintained at less than or equal to 1 to 1. The compounds thus produced are particularly useful as reactive cross-linkers in the production of polyurethanes and polyepoxides.

Abstract: This invention relates to solid reaction products of aliphatic, cycloaliphatic or araliphatic mono- and/or polyisocyanates and organic, weakly acid mono- and/or polycarboxylic acids for the production of cellular plastics articles and particularly polyurethane foams. The products of the present invention may also be in the form of mixtures with carboxylic acids. The products are suitable for the production of cellular or porous plastics articles, but are preferably used in the preparation of cellular thermoplastic polyurethanes and semi-rigid and particularly rigid polyurethane integral skin foams having a compact outer skin formed by foaming the reaction mixture in closed molds.

Abstract: This invention relates to a process for the preparation of compounds which contain s-triazine units and isocyanate groups or isocyanate-reactive groups and which melt without decomposition, by the reaction of triisocyanates containing s-triazine units with compounds containing isocyanate-reactive groups, and the use of these products as fillers which can be chemically fixed in the production of polyurethanes by the isocyanate polyaddition process.

Abstract: This invention relates to mixtures of polyols which are liquid at room temperature with functional aldoximes as blowing agents, wherein the aldoxime groups react with polyisocyanates to liberate carbon dioxide and are simultaneously incorporated by means of the functional group thereof into the polyurethane formed. The present invention also relates to a process for the production of polyurethane foams using these incorporated reactive blowing agents as the primary blowing agent in combination with blowing agents known in polyurethane chemistry. The process according to the invention described herein is suitable for the production of various polyurethane foams or cellular polyurethane elastomers, particularly including the production of semi-rigid and rigid polyurethane integral skin foams which are obtained by foaming the reaction mixture in closed molds.