Abstract: Polyamines are produced by hydrolyzing an isocyanate compound in the presence of at least one of a selected group of catalysts and a water miscible polar organic solvent in substantially homogeneous phase at 40.degree.-170.degree. C. The catalyst employed is selected from potassium hydroxide, rubidium hydroxide, cesium hydroxide, potassium alcoholates, rubidium alcoholates, cesium alcoholates, potassium carboxylates, rubidium carboxylates and cesium carboxylates. These polyamines are useful in the production of polyurethane(urea)s.

Abstract: The present invention is directed to a process for the production of a thixotropic agent by reacting a polyisocyanate containing a uretdione group with a polybasic carboxylic acid containing at least one carboxyl group and, optionally, OH groups. The present invention is also directed to thixotropic high molecular weight polyols containing the above thixotropic agent. Finally, the present invention is directed to storable, reactive polyurethane systems comprising thixotropic polyols and polyisocyanates which are essentially unreactive with the polyols at room temperature.

Abstract: A composite plastic molding made up of a plastic foam and having a polyurethane skin is made by heating a reactive one-component system to form a polyurethane skin and then joining the polyurethane skin to the plastic foam. The one-component system is composed of a finely divided polyisocyanate in which from 0.1 to 25 equivalent percent of the isocyanate groups have been deactivated, a polyamine and/or polyol having a molecular weight of from 400 to 8000 and optionally a chain extending agent, a catalyst and known auxiliaries and additives.

Abstract: Polyurethanes containing uretdione rings are produced by reacting a polyisocyanate containing a uretdione ring with a relatively high molecular weight dihydroxyl compound in the presence of a bismuth salt of an organic carboxylic acid and a low molecular weight aromatic diamine. The low molecular weight aromatic diamine is used in a quantity which is 5 to 10 times the quantity of bismuth salt used. These solid polyurethanes are formed in relatively short reaction times and possess outstanding mechanical properties.

Abstract: The invention relates to a process for the in situ production of dispersions or solutions of urea group-containing aromatic isocyanates by the low temperature reaction of aromatic diisocyanates and/or polyisocyanates (the NCO groups of which preferably exhibit different reactivities) with from 0.15 to 0.4 mols of water per NCO equivalent in relatively high molecular weight polyols and in the presence of catalysts accelerating the NCO/water reaction. Such catalysts are preferably selected from peralkylaminoalkyl ethers, peralkylamino-polyalkylene ethers and/or peralkyl-polyalkylene-polyamines. The present invention also relates to the resulting metastable solutions or dispersions and to the use thereof, optionally with the further addition of relatively high and low molecular weight compounds having hydroxyl, amino or hydrazide groups and with the optional addition of other polyisocyanates in polyurethane-forming ratios for the production of polyurethanes.

Abstract: The present invention is directed to a process for the preparation of finely divided solid polyisocyanates containing urea groups by reacting organic polyisocyanates which are free from urea groups with water in an aqueous emulsion, characterized in that the reaction is carried out in the presence of an emulsion- and dispersion-stabilizing compound.

Abstract: 4,4'-dinitrodibenzyls are prepared by reaction of 4-nitrotoluenes, in the presence of an organic solvent and/or diluent, with an alkali metal-alcoholate and/or an alkaline earth metal alcoholate, and subsequent treatment of the reaction mixture with an aqueous solution of hypohalous acids and/or their salts or with chlorine, bromine or an aqueous solution of hydrogen peroxide and/or its salts, or with organic or inorganic peracids and/or their salts.

Abstract: A polyurethane-based reactive mass composed of(a) at least one organic compound in the molecular weight range of from 400 to 12000 containing isocyanate reactive groups and having a functionality from 2 to 8,(b) optionally an organic compound in the molecular weight range of from 62 to 399 containing isocyanate reactive groups and having a functionality from 2 to 8.(c) catalysts,(d) aliphatic isocyanate compounds and(e) optionally other auxiliary agents and additives known per se,characterized in that the aliphatic isocyanate compound used is one based on hexamethylene diisocyanate, hydrogenated diphenylmethane diisocyanate or isophorone diisocyanate containing isocyanurate and/or uretdione units and/or urethane and/or uretoneimine and/or oxadiazatrione groups is suitable for the production of lightfast coatings, including coatings in light colors, in particular for the formation of edgings round wooden panels without these panels having first to be dried down to the maximum dampness of 7% by weight.

Abstract: The present invention relates to a process for the dimerization of 4,4'-diisocyanatodiphenylmethane from emulsion in apolar solvents with the formation of complexes and to the complexes obtainable for the first time by this process. The complexes consist of one mol of low molecular weight 4,4'-diisocyanato-diphenylmethane-uretdione or its low oligomers corresponding to the idealized formula (I) ##STR1## (n=0 to 0.5, where n is the average degree of oligomerization of the dimer) and 2 to 3 mol of 4,4'-diisocyanatodiphenylmethane (MDI) ##STR2## In the process according to the invention, 4,4'-diisocyanatodiphenylmethane (II) in the molten form is emulsified in apolar solvents. Dimerization is started in the presence of conventional dimerization catalysts at temperatures above the melting point of MDI, preferably up to an upper temperature limit of 50.degree. to 60.degree. C. The temperature is then lowered to <40.degree. C. If desired, dimerization can be stopped when an isocyanate content of from 22.4 to 26.

Abstract: The present invention relates to cold setting compositions of (A) suspensions of solid polyisocyanates with retarded reactivity in aliphatic polyamines, and which are stable under storage due to a polyadduct covering, and (B) polyols and/or water. The activation of the composition is caused by the polyol or water. Additional activating materials can also be added for hardening. Such compositions, which already harden at ambient temperature, are stable under storage, have a long potlife for processing and, in relation to the potlife, have a very short hardening time to the final reaction product.

Abstract: The present invention is directed to a process for the production of urea group-containing, finely divided solid polyisocyanates by emulsifying or suspending a urea group-free organic polyisoycanate in an excess of water so that said organic polyisocyanate amounts to about 1 to 65% by weight of the reaction mixture, said water containing about 0.01 to 5% by weight, based on the aqueous phase, of a protective colloid and reacting the organic polyisocyanate with water to yeild a urea group-containing polyisocyanate.

Abstract: This invention relates to the production of polymer-coated, finely divided polyisocyanates by mixing(A) solid, finely divided polyisocyanates (preferably dimeric diisocyanates or urea diisocyanates) with(B) polyisocyanates differing in composition from those mentioned under (A) (preferably (cyclo) aliphatic polyisocyanates, such as biuretized diisocyanates or trimers or NCO-prepolymers),in quantities of from 0.05 to 50 parts by weight, and preferably in quantities of from 0.2 to 25 parts by weight, of (B) per 100 parts by weight of (A). The solid polyisocyanate particles surface-modified by covering with polyisocyanates (B) and then reacted with(D) isocyanate-reactive compounds containing reactive hydrogen atoms or with compounds free from active hydrogen atoms which form polymers with isocyanates in sub-equivalent to substantially equivalent quantities (preferably 0.5 to 1.

Abstract: This invention relates to new tetrahydropyrimidines, to a process for their production and to their use as catalysts in the production of polyurethane plastics, including polyurethane foams.

Abstract: This invention relates to a process for the production of solid polyamines stabilized by a polyadduct covering and showing retarded reactivity comprising reacting(1) one or more solid organic polyamines in particulate form, said polyamines containing at least two primary and/or secondary amino groups and having melting points above 50.degree. C., and(2) from 0.1 to 25 equivalent % of isocyanate per amine equivalent of a water insoluble, difunctional and/or higher functional polyisocyanate,said reaction being conducted at a temperature below the melting point of said solid polyamine, and being conducted in the presence of(3) a liquid medium selected from the group consisting of(a) organic compounds containing two or more hydroxy groups and having molecular weights of from 62 to 10,000,(b) plasticizers,(c) water, and(d) mixtures thereofto form a suspension of polyadduct-covered stabilized polyamines in the liquid medium.

Abstract: The invention relates to novel compositions for coating purposes comprising(A) polyvinyl plastisols,(B) surface modified, finely divided, stabilized polyisocyanates with retarded reactivity, in which 0.1 to 25 equivalents-% of the isocyanate groups of the unstabilized polyisocyanate have been deactivated on the surface, preferably by a reaction with polyamines, hydrazine, alkylhydrazines, polyhydrazide compounds and/or selected amidine and/or guanidine compounds; and(C) plasticizers and/or lightly branched, relatively high molecular weight polyhydroxyl compounds having melting points below 60.degree. C. and compatible with PVC plastisol.The invention also relates to the use of these storage stable but heat curable mixtures as primers for PVC coatings on plastics, foils, textile sheet products or filaments and as primer coats for flocking.

Abstract: The present invention is directed to a process for the production of suspensions of finely-divided polyisocyanates which are obtainable by the surface reaction with from 0.1 to 25 equivalent percent of reactive group per NCO of stabilizers in relatively high molecular weight polyols and/or relatively high molecular weight polyamines having molecular weights from 400 to 6,000 optionally with addition of lower molecular weight polyols and/or aromatic amines having molecular weights of from 60 to 399, which are characterized in that unreacted quantities of stabilizers in the suspension are subsequently partially or completely deactivated by addition of substances having an acylating and/or neutralizing and/or alkylating effect and/or adsorbing effect as "deactivators". In particular, mono- and/or polyisocyanates are used as "deactivators".

Abstract: The invention relates to a process for the in situ production of dispersions or solutions of urea group-containing aromatic isocyanates by the low temperature reaction of aromatic diisocyanates and/or polyisocyanates (the NCO groups of which preferably exhibit different reactivities) with from 0.15 to 0.4 mols of water per NCO equivalent in relatively high molecular weight polyols and in the presence of catalysts accelerating the NCO/water reaction. Such catalysts are preferably selected from peralkylaminoalkyl ethers, peralkylamino-polyalkylene ethers and/or peralkyl-polyalkylene-polyamines. The present invention also relates to the resulting metastable solutions or dispersions and to the use thereof, optionally with the further addition of relatively high and low molecular weight compounds having hydroxyl, amino or hydrazide groups and with the optional addition of other polyisocyanates in polyurethane-forming ratios for the production of polyurethanes.

Abstract: The present invention relates to the use of thermosetting polyurethane urea reactive adhesive compositions which are stable at ambient temperature but rapidly set at higher temperatures, wherein the adhesive comprises stabilized finely-divided polyisocyanates of retarded reactivity of which 0.1 to 25% of the NCO-groups are surface-modified and higher and/or lower molecular polyamines (optionally with polyols as additional reactive components). An important feature of these thermosetting reactive adhesive compositions is their capacity for storage at ambient temperature and their spontaneous increase in viscosity at relatively low heating temperatures which prevents the adhesive from running off during the heating period when applied to vertical surfaces.

Abstract: Polyurethane urea elastomers are produced by reacting polyisocyanates with compounds containing at least two isocyanate reactive hydrogen atoms having a molecular weight of 400 to 10,000 and mononuclear or dinuclear aromatic diamines. The aromatic diamines must have at least one sulfonamide group as a substituent on at least one of their aromatic rings. Known chain lengthening agents, activators, blowing agents, auxiliary agents and additives may also be included in the reaction mixture.Polyurethane elastomers produced by this process have excellent mechanical properties. In particular, such elastomers are soft yet have high tear propagation resistance.

Abstract: Urethane-modified polyisocyanates having an NCO-content of from 5 to 45 wt. % are made by reacting an organic polyisocyanate or mixture of polyisocyanates having an NCO-content of from 30 to 50 wt. % with an organic polyhydroxyl compound or mixtures of polyhydroxyl compounds. The organic polyhydroxyl compound must include at least 10 hydroxyl equivalent percent of an alkoxylation product of a bisphenol corresponding to a specified formula containing two alcoholic hydroxyl groups and having an OH number of from 112 to 389. The reactants are employed in quantities such that the NCO:OH equivalent ratio is from 2:1 to 50:1. The urethane-modified polyisocyanates of the present invention are particularly useful in the production of polyurethanes by the isocyanate polyaddition process.