Abstract: A wound dressing material comprising a sheet of a synthetic plastics material which is permeable to water vapour and to air, having on one side a surface for application to a wound, and immediately behind the said surface a cellular region having a structure of collapsed, open cells which intercommunicate with one another, and a more dense region behind the cellular region, and an intermediate region in which there is a gradual transition from the cellular region to the more dense region, so that on contact with liquid exudate from a wound, the dressing material will absorb a limited amount of exudate into the cellular region but prevent it from passing right through the dressing material.

Abstract: The present invention relates to a new process for the production of elastomeric polyurethane moldings which may be microcellular having a sealed surface layer and an average density of from 0.8 to 1.4 g/cm.sup.3, wherein specific condensation products of ricinoleic acid are used as internal mold release agents.

Abstract: A release agent is described, which is suitable for the production of polyurethane foam articles in molds. It is an aqueous emulsion or dispersion of per se known release-effective substances as well as optionally conventional additives, having a water content of at least 60% by weight and preferably 85 to 96% by weight, the water being masked through the effect of lyotropic mesomorphism. Masking and immobilizing the water molecules avoids that the water molecules have a prejudicial effect of the polyol/isocyanate reaction, and is preferably achieved by the combined use of release-effective substances and suitable masking aids. As suitable masking aids especially fatty alcohol polyglycol ethers and ethoxylated fatty alcohols are proposed. The polyurethane articles obtained while using the above described release agent fulfil the standard quality requirements without any of the disadvantageous effects on the environment such as occur with conventional release agents.

Abstract: The present invention is directed to a process for the production of optionally cellular, polyurethane and/or polyurethane-urea moldings having an impervious skin by reacting in a closed mold a reaction mixture containing(a) at least one organic polyisocyanate,(b) at least one compound which has a molecular weight of about 400 to 12,000 and at least two isocyanate-reactive groups, and(c) optionally at least one compound which has a molecular weight of from 32 to 399 and at least two isocyanate-reactive groups,wherein before the reaction takes place a surface-improving additive (e) is added containing(e1) a liquid and sedimentation-stable polymer dispersion which is produced by the free radical addition polymerization or copolymerization of one or more olefinically unsaturated monomers in a high molecular weight compound having isocyanate-reactive groups of the type mentioned in (b),and optionally(e2) a metal salt of a monocarboxylic acid having at least 8 carbon atoms in the moleculewherein additive (e) is us

Abstract: A catalyst composition for improving the reaction-cure rate of polyurethane compositions derived from poly aliphatic isocyanate compounds and poly-hydroxyl bearing compounds is disclosed. The catalyst composition consists essentially of(a) from about 25 to about 75 parts by weight of lead naphthenate; and(b) from about 75 to about 25 parts by weight of at least one dialkyltin dicarboxylate compound of the formula: ##STR1## wherein R is selected from C.sub.1 to C.sub.8 alkyl and R' is selected from C.sub.1 to C.sub.18 alkyl, based upon 100 parts by weight of said catalyst composition.The catalyst compositions promote sufficiently rapid cure rates such that injection moldable poly aliphaticisocyanate-based polyurethane compositions may be provided. In a preferred embodiment, new and improved integral skin foam polyurethane compositions are disclosed which may be reaction injection molded to form integral skin foam shaped articles exhibiting ultraviolet light resistance and improved colorability.

Abstract: A thermoset polyurethane material which exhibits high, temperature-insensitive damping over a broad temperature range and has a tan .delta. (as hereinbefore defined) greater than 0.1 over the temperature range of from -40.degree. C. to 60.degree. C., a hardness in the range of from 0 to 90 Shore A, a compression set (as hereinbefore defined) of less than 15% and a tensile strength (as hereinbefore defined), of less than 30 kg/cm.sup.2, the polyurethane material being prepared by the reaction of(a) an essentially primary hydroxyl tipped polyol having a molecular weight in the range of from 2,500 to 8,000;(b) a polyhydric alcohol;(c) an aliphatic monohydric primary alcohol containing up to 10 carbon atoms; and(d) a polyisocyanate, the reaction being carried out at a isocyanate index of 1.0 or greater.

Abstract: A polyurethane integral hard foam construction panel comprises a denser edge zone and a porous core, the surface of the construction panel being enameled, and is used as a roofing plate, in particular as a small format, nailed roof cover plate.For that purpose the invention provides that the polyurethane integral hard foam of the construction panel includes fillers, namely 1 to 65% by weight flame-retardants such as aluminum hydroxide [Al(OH).sub.3 ] and/or Exolite and 1 to 90% slate powder.

Abstract: The invention relates to a one-shot process for the preparation of cellular or noncellular polyurethane polyurea parts having a modulus of flexural elasticity greater than 600 N/mm.sup.2 and densities of from 0.8 to 1.2 g/cm.sup.

Abstract: The invention relates to a process for the preparation of elastomeric molded parts having urethane or urethane and urea linkages which comprises reacting(a) an organic polyisocyanate,(b) a polyhydroxyl compound selected from the group consisting of(i) polyester polyols with molecular weights of 1000 to 3000 and hydroxyl numbers of 170 to 35 produced by polycondensation of organic dicarboxylic acids and a polyol mixture of at least 3 polyols;(ii) polyether polyols having terminal ester groups, molecular weights of 1000 to 8000 and hydroxyl numbers of 170 to 15; and(iii) mixtures thereof;(c) a chain extenderwherein components (a) through (c) are processed according to reaction injection molding techniques in open or closed molds.The reaction is preferably carried out as a one-shot process and may also be carried out in the presence of blowing agents (d), auxiliaries (e), and additives (e).

Abstract: The present invention is directed to a process for the production of a molded article having a compact surface layer and a gross density above 900 kg/m.sup.3 via the reaction injection molding technique, comprising introducing a reaction mixture into a closed mold, said reaction mixture comprising:(a) a polyisocyanate component consisting of at least one polyisocyanate in which all the isocyanate groups are aromatically bound,(b) compounds having molecular weights of from 400 to 12,000 and having at least two isocyanate reactive hydrogen atoms,(c) water, in a quantity of at least 0.

Abstract: Homogeneous storable mixtures containing small quantities of salts and having a high mixed hydroxyl number of mixed hydroxyl/amine number are made by mixing (a) a polyoxyalkylene polyol and/or polyolamine and/or polyamine based on an alkyloxirane having a molecular weight of from 400 to 12,000, (b) a low molecular weight polyol which is not completely miscible with (a) and a solution-promoting additive in quantities such that for every 100 parts of (a), from 1 to 200 parts of (b) and from 0.01 to 10 parts of (c) are present. The solution-promoting additives are salts of cations of Groups IA, IIA and IIIA of the Periodic System of Elements or ammonium or mono- to tetra-alkylammonium ions and anions formed by removing at least one proton from an acid having a K.sub.s -value of at least 10.sup.-7. These mixtures are particularly useful in the production of polyurethanes.

Abstract: A polyimide and a process for its preparation wherein the polyimide is prepared from reaction of an organic tetracarboxylic acid or derivative thereof with a mixture of an aromatic diamine and an amine-terminated butadiene-nitrile copolymer. The polyimides of the invention are particularly useful in the preparation of flexible foams.

Abstract: There are provided improved integral skin microcellular polyether polyurethane elastomer products, e.g., shoe soles, which are characterized by outstanding low temperature dynamic flex and green strength at demold, at specific gravities as low as about 0.4 gm/cc. These elastomer products are desirably prepared from a two-component system, e.g., the reaction of Component A containing improved quasi-prepolymers, with Component B comprising a compatible liquid mixture containing poly(oxyethyleneoxypropylene)polyol, difunctional chain extender, halogenated blowing agent and other ingredients, as needed, over a relatively wide isocyanate index range without the drawback of any significant loss in the elastomer properties due to index fluctuation within said range.Improved integral skin microcellular polyether elastomers of low densities, e.g., 0.

Abstract: A catalyst composition for improving the reaction-cure rate of polyurethane compositions derived from poly aliphatic isocyanate compounds and poly-hydroxyl bearing compounds is disclosed. The catalyst composition consists essentially of(a) from about 25 to about 75 parts by weight of lead naphthenate; and(b) from about 75 to about 25 parts by weight of at least one dialkyltin dicarboxylate compound of the formula: ##STR1## wherein R is selected from C.sub.1 to C.sub.8 alkyl and R' is selected from C.sub.1 to C.sub.18 alkyl, based upon 100 parts by weight of said catalyst composition.The catalyst compositions promote sufficiently rapid cure rates such that injection moldable poly aliphatic-isocyanate-based polyurethane compositions may be provided. In a preferred embodiment, new and improved integral skin foam polyurethane compositions are disclosed which may be reaction injection molded to form integral skin foam shaped articles exhibiting ultraviolet light resistance and improved colorability.

Abstract: A catalyst composition is disclosed for polyurethane production by reaction between aliphatic hydroxyl-containing compounds and secondary or tertiary aliphatic isocyanate group-containing compounds, comprising (i) 1,8-diazabicyclo(5.4.0)-undecene-7, or a salt thereof; (ii) an organic tin compound and, optionally, (iii) an organic lead compound.

Abstract: The present invention is directed to a process for the production of a flexible polyurethane foam comprising reacting(a) an organic polyisocyanate, and(b) a coupled polyol which consists essentially of the reaction product of an organic polyisocyanate and an organic compound having a hydroxy functionality of at least 2 and a primary hydroxy group content of at least 30%, the ratio of hydroxyl groups in said organic compound to isocyanate groups being greater than 1,(c) in the presence of(i) a blowing agent,(ii) a catalyst, and(iii) a foam stabilizer, said foam stabilizer being capable of producing a flexible polyurethane foam meeting the standard specifications for high resilience polyurethane foam as set forth in ASTM D-3770-79, when used in a foam formulation based on toluene diisocyanate and either (A) a polymer polyol prepared by polymerizing one or more ethylenically unsaturated monomers in a polyether polyol, or (B) a dispersion of polyurea and/or polyhydrazodicarbonamide in a hydroxyl group containing

Abstract: An improved process for the reaction injection molding of high flexural modulus polyurea containing elastomers is disclosed. Elastomers of this type when prepared at the prior art molding temperatures are brittle and can shatter like glass while still in the mold. The same elastomers when molded at a temperature of from about 90.degree. to about 220.degree. C. are not at all brittle. These elastomers are also characterized by the other advantageous properties inherent in polyurea elastomers such as high tensile strength, high hardness, and good heat resistance.The improved RIM process finds particular utility in the preparation of auto parts such as panels, engine hoods, and the like.

Abstract: The invention relates to the use of poly-N,N-di-(hydroxyalkyl)-polycarbonamides of aliphatic or cycloaliphatic polycarboxylic acids as reactive flame-retardants for polyurethane foams, and in particular polyurethane integral skin foams and polyurethane rigid foams which are produced with the aid of organic blowing agents. These reactive flame-retardants are added in quantities of from 11.5 to 50 parts by weight, and most preferably from 12 to 25 parts by weight, based on 100 parts of the relatively high molecular weight polyol used for the preparation of the foam. The integral skin or rigid foams produced are flame-resistant and because of their reduced flammability are capable of passing various regulation fire tests, and in particular those testing foams for use in vehicles for transport.

Abstract: Dialkyl diamines for use with polyols and polyisocyanates in cast elastomer and reaction injection molding polyurethane processes. The dialkyl diamines are prepared by nitration and reduction of dialkylbenzenes or alkylation of meta-phenylenediamine. The chain extenders have the following structure: ##STR1## where R.sub.1 is C.sub.1 -C.sub.6 alkyl or C.sub.3 -C.sub.6 cycloalkyl and R.sub.2 is C.sub.2 -C.sub.6 alkyl or C.sub.3 -C.sub.6 cycloalkyl.Contrary to the teachings of the prior art the novel diamines have surprisingly good reaction times to form polyurethanes with excellent physical properties. Furthermore, little or no mold release is required in RIM and other processes using the chain extenders of the invention.

Abstract: A process for producing a shaped article of a non-cellular or microcellular polyurethane elastomer by reaction injection molding by using at least two components of (A) a polyol component comprising a high molecular weight polyol and a chain extender as essential ingredients and (B) an isocyanate component comprising a polyisocyanate compound as essential ingredient, characterized in that substantially all or at least 80% by weight of said high molecular weight polyol is composed of a polyoxyalkylene polyol, and the polyoxyalkylene polyol is a single or mixed polyoxyalkylene polyol which has an average hydroxyl number of from 2.0 to 3.5 and an average hydroxyl value of from 15 to 60 and contains at least 5% by weight, in an average, of oxyethylene groups at the terminal portions of the oxyalkylene chain and in which the total oxyethylene group content is, in an average, less than 21% by weight and the average unsaturated monool content is at most 0.085 meq/g.

Abstract: There are provided a wide range of polyurethane products, e.g., cellular, dense elastomer, and integral skin microcellular products, obtained by the reaction of (a) a polyisocyanate compound, (b) a polyol, (c) optionally a chain extender and/or blowing agent with/without other known additives, (d) in the presence of a non-hydroxyl flow modifier characterized by carbon and hydrogen atoms, at least one and, generally, a plurality of oxyalkylene groups, and at least one urethane, ##STR1## group. Several of the polyurethane products exhibit unique properties, e.g., foamed articles with capability to conduct static electricity, soft elastomers characterized by improved coefficient of friction, etc. Several classes of the flow modifiers are novel per se. The polyurethane products can be synthesized via the one shot or prepolymer process. Multipackage systems, in particular, two and three component systems are useful in molding operations, e.g., manufacture of shoe soles.

Abstract: A method of manufacturing polyurethane foam by a reaction of organic polyisocyanates and polyols in the presence of a foaming agent and catalysts comprises using as the catalyst, a salt of carbonic acid and polyamine represented by the general formula: ##STR1## wherein R.sub.1 and R.sub.2 are an alkyl group having 1-4 carbon atoms or R.sub.1 and R.sub.2 are combined to form a heterocyclic ring having 3-6 carbon atoms together with a nitrogen atom; and R.sub.3 is an alkylene group.

Abstract: A cellular polyurethane having a density of from 15 Kg/m.sup.3 to 400 Kg/m.sup.3 obtained by means of thermoforming, in a forming tool, at a compression factor of from 1 to 10 and temperatures of from 140.degree. C. to 200.degree. C., polyester-urethane foams having a density of from 15 Kg/m.sup.3 to 40 Kg/m.sup.3 which are based on aromatic polyisocyanates and polyester polyols. The resulting polyurethane shaped objects are suitable for use as self-supporting trim panels, headliners, engine compartment covers, or instrument panels in the automotive, aircraft or railway industries.

Abstract: 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

Abstract: Reaction injection moldings (RIM) having increased heat resistance are provided by substituting a thiapolycyclic polyisocyanate such as dimethyl-9-thiabicyclononane diisocyanate for the aromatic polyisocyanate in an otherwise conventional RIM composition.

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: An unfoamed permeable material, which absorbs and desorbs moisture satisfactorily and which is suitable for making thin-walled articles having a maximum thickness of 3 mm, is based on plastic and/or rubber mixtures containing macromolecular hydrophilic fillers. The hydrophilic fillers are synthetic, water insoluble, cross-linked macromolecular materials containing pendent polar groups, which are able to bind water reversibly, e.g. hydroxy, amine, amide, carboxylic and sulfonic groups in H.sup.+, Na.sup.+, K.sup.+, Li.sup.+, Ca.sup.++, or Ba.sup.++ form, or quaternary ammonium groups in CH.sup.-, Cl.sup.- or HSO.sub.4.sup.- form.

Abstract: The invention relates to reaction injection molded elastomers containing a major amount of polyurea linkages derived from high molecular weight amine terminated polyethers, an aromatic diamine chain extender and a polyisocyanate. The reaction injection molded (RIM) elastomers of this invention are useful, for example, as automobile body parts.

Abstract: Integral skin polymethane foams can be produced in a short time by impingement mixing a solution comprising polyols containing as an essential component a polyol derived from aromatic amine, a blowing agent and a special catalyst of tertiary amine salt having a hetero ring in the molecule, with a solution comprising one or more polyisocyanates, followed by injection into a closed mold and foaming and curing therein.

Abstract: A process for the production of optionally cellular molded articles with a smooth outer skin and improved surface characteristics by the reaction, inside a closed mold, of a mixture of one or more organic polyisocyanates, one or more compounds having molecular weights of from 400 to 12,000, which contain at least two isocyanate-reactive groups, chain-linking and/or chain-extending agents, and optionally, known auxiliary agents and additives used in polyurethane chemistry, characterized in that before the reaction, surface-improving additives comprising one or more polymers or copolymers of one or more olefinically-unsaturated monomers, which polymers or copolymers have molecular weights of from 200 to 50,000, are liquid at room temperature, soluble in the reaction mixture, and inert toward isocyanate groups and at least one metal salt of a monocarboxylic acid having at least 8 carbon atoms, are incorporated into the reaction mixture.

Abstract: A process for producing injection molded articles of foamed thermoplastic material via injecting of a molten mass of thermoplastic material containing a foaming agent into a mold cavity is improved so as to substantially reduce production time by the utilization of a step introducing a cold compressed gas into the mold cavity internally of the injected mass of material, while it is still at least internally molten. The article produced by the process is characterized by an outer skin of tightly structured material surrounding a body of microcellular foam material having an internal void or voids bounded by material of a tightly structured nature.

Abstract: The invention relates to reaction injection molded elastomers containing a major amount of polyurea linkages derived from high molecular weight amine terminated polyethers, an aromatic diamine chain extender and a polyisocyanate. The reaction injection molded (RIM) elastomers of this invention are useful, for example, as automobile body parts.

Abstract: The invention is a method of making a molded reaction injection molded elastomer which will release from its mold without the presence of externally applied mold release agents. The reaction injection molded (RIM) elastomer is made by injecting exactly two streams via a RIM machine into a mold cavity of the desired configuration, a formulation comprising in the first stream amine terminated polyethers of greater than 1,500 molecular weight, an amine terminated chain extender and an internal mold release agent, and in the second stream an aromatic polyisocyanate. The resulting RIM elastomer may be removed from the mold easily. RIM elastomers are useful, for example, for automobile body parts.

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: A deformable and durable polyurethane foam molding is made from the reaction product of a polyether polyol component and a polyisocyanate component. The polyether polyol component is a polyether having at least two hydroxyl groups, a molecular weight of from 400 to 10,000 and at least 10 wt. % hydroxyl groups which are primary hydroxyl groups. The polyisocyanate component is a mixture of from 60-90 wt. % 4,4'-diphenyl methane diisocyanate and from 3-30 wt. % 2,4'-diphenyl methane diisocyanate. Such reaction mixture is prepared in each of at least two mixing heads. The index of reaction mixture is different from that in the other mixing head. The mixture is then introduced into associated zones of a mold cavity where the mixture is allowed to foam. The molding is subsequently removed from the mold cavity. These polyurethane foam moldings are particularly useful in making seat cushions.

Abstract: The invention concerns a process for the preparation of flexible polyurethane foams having good hydrolytic stability, improved damping, with equal or higher levels of other physical properties and with a high absorption capacity. The foams are prepared by reacting organic polyisocyanates and mixtures of(a) liquid polyester polyols, which are produced by the polycondensation of organic dicarboxcylic acid and a polyol mixture which contains 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and at least one triol, and(b) di- to tetra-functional polyether polyols having molecular weights of 1500 to 6000in the presence of catalysts and blowing agents as well as optionally chain extenders, auxiliaries, and additives.

Abstract: The use of certain prepolymers of 4,4'-methylenebis(phenyl isocyanate), in place of the latter diisocyanate itself in the preparation of polyurethane-polyureas using aromatic diamine extenders, has a number of advantages particularly when the compositions are prepared by reaction injection molding techniques using two streams of reactants. The principal advantages are (i) a useful increase in gel time and (ii) a ratio of amounts of the two reactant streams which more nearly approaches 1:1.This latter factor not only improves the efficiency of mixing of the components in the mixing head but, together with the longer gel time, significantly increases the output of mixed reactants per unit of time. The prepolymers of 4,4'-methylenebis(phenyl isocyanate) employed to achieve the above results are those derived from polyoxyethylene polyoxypropylene polyether diols and triols (MW=1000-10,000), polytetramethylene glycols (MW=600-5,000) and polyester diols and triols (MW=500-8,000).

Abstract: A method for making closures resembling natural cork for sealing liquid product containers is described. A strand of expandable plastic material is injected into each mold cavity and is permitted to collect in that cavity in randomly oriented groups of coils which expand to fill the cavity and coalesce to create randomly oriented grain lines on the surface of the closure resembling the appearance of natural cork. Also described are methods of molding the closures which preclude the formation of leakage channels on the closure surface and preferred blends of plastic resins and pigment particles used to achieve the cork-like appearance.

Abstract: Polymer foam is extruded as a tube or sheet into a cooling liquid which is maintained at a temperature up to about 85.degree. C. Either one or both surfaces of the polymer are cooled as the extrudate emerging from the die orifice passes through the liquid. Styrenic polymer foam extrudate produced by such a method exhibits excellent puncture resistance and tensile properties.

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.

Abstract: A molded object having a sponge-like interior surrounded by a skin, molding composition from which it is produced, and the method for producing the article. Copolymers of vinyl-substituted aromatic compounds containing from 8-18 carbon atoms copolymerized with conjugated diene having from 4-12 carbon atoms and polymer chosen from among solid resinous polymers of vinyl-substituted aromatic compounds present in amounts ranging from about 10 to about 75 parts by weight per 100 parts by weight of the copolymer and solid resinous copolymers of ethylene present in an amount of about 5 to about 50 parts by weight per 100 parts by weight of the copolymer are blended with a sufficient amount of polarizing agent to achieve rapid heating through response to microwave treatment, blowing agent in an amount sufficient to provide a sponge-like, rubbery porosity to an article molded therefrom, and, optionally, cellular control agent.

Abstract: A novel elastomer having a very low compression set and a very slow recovery from compression comprises a flexible polyurethane of essentially linear structure containing unsatisfied hydroxyl groups, and is the reaction product of substantially linear polyols having hydroxyl end groups and an average molecular weight in the range 600 to 1200, with an aromatic isocyanate in less than stoichiometric amount. This elastomer can be used as one layer of an energy-absorbing material, in combination with a more difficultly compressible layer comprising a tough flexible polymeric matrix having a plurality of rigid hollow bodies embedded therein.

Abstract: The instant invention relates to a process for the production of polyurethane foams by reacting polyisocyanates with polyhydroxyl compounds of a specified molecular weight range in the presence of blowing agents and chain lengthening or cross-linking agents and optionally in the presence of catalysts, foam stabilizers and other additives generally known. The improvement resides in(a) the polyisocyanates used containing aliphatically and/or cycloaliphatically bound isocyanate groups;(b) the polyhydroxyl compounds used containing ether groups; and(c) the chain lengthening or cross-linking agents comprising at least in part a member selected from the group consisting of a monoalkoxylated hydrazine, a dialkoxylated hydrazine, a reaction product of a monoalkoxylated or dialkoxylated hydrazine with an aliphatic monoisocyanate in a molar ratio of 1:1. The reaction is carried out in the presence of additional chain lengthening agents having a specified molecular weight.

Abstract: This invention relates to an improved single-stage process for the production of elastic shaped articles having an impervious surface layer by the reaction injection molding technique in which highly reactive systems of polyisocyanates, relatively high molecular weight polyhydroxyl compounds and aromatic polyamines are used.

Abstract: The instant invention is directed to a process for the production of polyurethane urea elastomers having a gross density of more than 200 kg/m.sup.3 comprising: casting a reaction mixture of(A) an isocyanate prepolymer produced from(a) 1 mole of a compound containing at least 2 Zerewitinoff-active hydrogen atoms and having a molecular weight of from 400 to 10,000 and(b) 2 to 10 moles of diisocyanatodiphenylmethane,(B) an aromatic diamine, and(C) 0 to 50 mole percent, based on component (B), of a polyol containing primary hydroxyl groups and having a molecular weight of from 62 to 6000, the equivalent ratio between component (A) and components (B) + (C) amounting to between 0.9:1 and 1.

Abstract: An improved process for preparing integral skin polyurethane, wherein a reaction mixture comprising polyol, polyisocyanate the NCO groups of which are not directly bonded to an aromatic group, no more than 0.5 part by weight of water to 100 parts by weight of polyol, and a catalyst is reacted in a mould, said improvement consisting in using as catalyst a synergistic combination of at least one organic initiator, comprising at least one functional group of primary or secondary amines, with at least one organic compound of bismuth.

Abstract: A process for preparing an integral-skinned polyurethane foam wherein a foamable composition for formation of polyurethane which comprises a polyol, polyisocyanate, cross-linking agent, catalyst, and blowing agent is reacted and expanded in a mold, characterized in that(a) said polyol is a polyether polyol having a terminal ethylene oxide adduct rate of at least 60%, an OH number of 20 to 100 and a functionality of 4 to 8, or a polyester polyol having a functionality of 4 to 8;(b) said polyisocyanate is a non-aromatic polyisocyanate having an isocyanate index of 90 to 130;(c) said cross-linking agent is diethanolamine and ranges from 0.5 to 20 parts by weight based on 100 parts by weight of said polyol;(d) said catalyst is an organometallic salt; and(e) said blowing agent is a halogenated hydrocarbon of a low boiling point.

Abstract: Synthesis of integral skin microcellular polyurethane elatomers by reacting hydroxyl-terminated aliphatic polyesters with symmetrical diisocyanates, prepolymers of these isocyanates such as derived from p,p'-diphenylmethane diisocyanate and an aliphatic glycol and mixtures thereof, these are polymerized in the presence of an organic blowing agent, and one or more plasticizers such as of the formulae ##STR1## further enhancement of the results is brought about by the presence of catalysts and cell regulating agents, such as dimethylpolysiloxanes; the obtained elastomers are useful, such as for shoe soles and in the manufacture of other products, e.g., vibration dampening devices, floatation devices, gaskets and the like.

Abstract: The instant invention is directed to a process for the production of molded foams having a compact surface and cellular core and an integral density distribution over the cross-section of the body, comprising reacting(A) polyisocyanates, and(B) relatively high molecular and/or low molecular compounds having an average of at least two isocyanate-reactive hydrogen atoms in the presence of:(C) catalysts for the isocyanate polyaddition reaction and(D) blowing agents and optionally other known additives, in a closed mold under the conditions of foaming inside molds, the improvement wherein said polyisocyanates are aliphatic and/or alicyclic polyisocyanates and said catalysts are catalyst combinations of:(i) an alkali metal and/or alkaline earth metal hydroxide and(ii) a metal compound, the metal compound being the acetylacetonate of iron, C.sub.1 -C.sub.

Abstract: To prepare light-stable polyurethane integral skin foams, especially soft integral foams, aliphatic and/or cycloaliphatic polyisocyanates, both categories preferably containing urethane groups and/or biuret groups, are reacted with polyols in the presence of blowing agents and of a synergistic catalyst combination comprising an alkali metal hydroxide, alkali metal alcoholate, alkali metal phenolate, alkali metal salt of a weak acid and/or hexahydrotriazine derivative and an organic tin, zinc and/or iron(II) compound, in the presence or absence of assistants and adjuvants.The preferred catalyst combination is tri-(dimethylaminopropyl)-s-hexahydrotriazine and dibutyl-tin dilaurate.