Abstract: A polyurethane/polyisocyanurate foam is obtainable from the reaction of A) a polyol component comprising A1) an aromatic polyester polyol, A2) a polyether polyol started on a carbohydrate polyol and A3) a polyether polyol started on ethylene glycol, wherein the total hydroxyl number of the polyol component A) is from ?150 mg KOH/g to ?300 mg KOH/g; with B) a polyisocyanate component, wherein the equivalent ratio of NCO groups to the sum of the hydrogen atoms reactive towards NCO groups is from ?110:100 to ?200:100. This foam has improved adhesion properties to facings and is suitable for the production of composite elements without requiring the use of an additional adhesion promoter.

Abstract: The present invention relates to a novel process for producing polyesteretherols via alkoxylation of polyesterols, and also to the use of the polyesteretherols for producing polyurethanes.

Abstract: The invention relates to a process for producing flexible polyurethane foams by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups in the presence of c) blowing agents, wherein the component b) comprises at least one polyether carbonate polyol bi) which can be prepared by addition of carbon dioxide and alkylene oxides onto H-functional starter substances using DMC catalysts and has a functionality of at least 2, a hydroxyl number in the range from 10 to 500 mg KOH/g and a content of incorporated carbon dioxide in the form of carbonate units of at least 2% by weight.

Abstract: A high resilience (HR) polyurethane foam comprising the reaction product of (1) at least one polyisocyanate comprising at least about 5 weight percent of at least one methylene diphenyl diisocyanate isomer, derivative or a combination thereof and (2) an admixture of at least one natural oil based polyol and at least one additional polyol which is not a natural oil based polyol, wherein the admixture comprises at least about 10 weight percent natural oil based polyol and at least about 40 weight percent additional polyol having an equivalent weight of at least about 1700 Daltons; and the foam has a resiliency indicated by a ball rebound of at least 40 percent as measured according to the procedures of ASTM D 3574, Test H.

Abstract: A two-component polyurethane/vinyl ester hybrid foam system is formed of a polyol component (A), which contains at least one polyol, a catalyst for the reaction of the polyol with the polyisocyanate, at least one polymerizable vinyl monomer and water or a blowing agent on the basis of a compressed or liquefied gas as foam-forming agent, and a polyisocyanate component (B), which contains at least one polyisocyanate and a catalyst for the polymerization of the vinyl monomer, and is designed for use as a flame retardant material and material for filling openings, cable and pipe bushings in walls, floors and/or of buildings for the purpose of fire protection.

Abstract: A multicomponent polyurethane/vinyl ester hybrid foam system for forming a gradient foam with soft and rigid foam regions, with a polyol component (A), a polyisocyanate component (B), and a component (C), which contains a catalyst for the polymerization of the vinyl monomer, with the polyol component (A) containing, as vinyl monomer, a mixture of vinyl esters of at least one polymerizable hydroxyvinyl ester and at least one branched, at least trifunctional, polymerizable vinyl ester, and the polyisocyanate component (B) containing a thermally activatable free radical-forming agent as catalyst for the polymerization of the vinyl monomers, with the proviso that the proportion by weight of the vinyl ester mixture is greater than the proportion by weight of the at least one polyol as well as the proportion by weight of the at least one polyisocyanate.

Abstract: A method of producing a viscoelastic polyurethane foam coating in which a polyisocyanate is reacted with a polyol to form a prepolymer. The prepolymer is reacted with a polyol having at least one pendant carboxylic acid group to form a prepolymer with a pendant carboxylic acid group. The prepolymer with a pendant carboxylic acid group is neutralized with a tertiary amine and then reacted with water or an organic or inorganic polyamine. An energy absorbing unit in which the coating produced by the above method is provided on a viscoelastic polyurethane foam layer.

Abstract: The invention provides B-sides of urethane formulations, wherein the B-sides comprise both alcohol and epoxy moieties. Also provided are urethane formulations comprising the B-side of the invention, as well as A-sides comprising isocyanate molecules.

Abstract: Process for preparing rigid urethane-modified polyisocyanurate foams from polyisocyanates and polyfunctional isocyanate-reactive components in the presence of a blowing agent, a metal salt trimerisation catalyst and a functionalised carboxylic acid.

Abstract: Flexible polyurethane foams are prepared by reacting a polyisocyanate with a high equivalent weight polyol. At least a portion of the high equivalent weight polyol is a polyester containing hydroxymethyl groups. The polyester is prepared in a multi-step process from animal or vegetable fats, by recovering the constitutent fatty acids, hydroformylating carbon-carbon double bonds in the fatty acids and reducing to form hydroxymethyl groups, and then forming a polyester by reaction with an initiator compound.

Abstract: This invention relates to fire-resistant, flexible, molded, medium density polyurethane foams. These foams typically have a density of from 10 to 30 pcf. The foams are the reaction product of a) at least one polyester polyol, b) at least one highly branched polyether polyol, c) at least one chain extender, d) a polymethylene poly(phenyl isocyanate), an isocyanate group containing prepolymer based on a polymethylene poly(phenyl isocyanate), or mixtures thereof, e) a solid flame retardant and f) water. This invention also relates to a process for preparing these polyurethane foams in open molds.

Abstract: A resin composition includes a polycarbonate resin derived from an ether diol residue such as isosorbide and has excellent impact resistance, heat resistance, heat stability and moldability. The resin composition includes a rubber polymer (component B) in an amount of 1 to 30 parts by weight based on 100 parts by weight of a polycarbonate resin (component A) which contains a recurring unit represented by the following formula (1) as the main constituent and has a glass transition temperature (Tg) of 145 to 165° C. and a 5% weight loss temperature (Td) of 320 to 400° C.

Abstract: Fire-resistant, medium density molded polyurethane foams which may be removed from a mold in substantially shorter times than previously possible are produced by the process of the present invention. These reduced de-mold times are achieved by including a solid flame retardant composition in the polyurethane foam forming composition. This solid flame retardant composition includes a melamine coated ammonium polyphosphate and zinc borate.

Abstract: A process for producing rigid polyurethane foams, in which a mixture of one or more high-functionality polyether alcohols having functionalities of from 3.5 to 5.5 and a hydroxyl number of from 350 to 550 mg KOH/g, one or more polyether alcohols based on aliphatic and/or aromatic amines and having functionalities of from 3 to 4 and a hydroxyl number of from 150 to 800 mg KOH/g, an OH-comprising fatty acid ester and, if appropriate, one or more low molecular weight chain extenders and/or crosslinkers having functionalities of from 2 to 3 and a molecular weight Mw of <400 g/mol is used as polyol component, is described. The rigid polyurethane foams obtained have a good surface quality.

Abstract: Process for the preparation of foamed thermoplastic polyurethanes characterised in that the foaming of the thermoplastic polyurethane is carried out in the presence of thermally expandable microspheres.

Abstract: An all-liquid foam-forming system contains: a first part (A) containing at least one liquid isocyanate or polyisocyanate; and a second part (B) containing: at least one liquid aromatic polyester polyol having an hydroxyl value of at least 110 mg KOH/gram and an average hydroxyl functionality of at least 2, at least two liquid halogenated flame retardants and water; the foam-forming system having an NCO/OH ratio of from about 0.9:1 to about 1.3:1; wherein the first and second parts are such that reaction therebetween forms a rigid polyurethane foam having a density of at least about 5 pcf and an ASTM E-84 Class 1 rating. Resultant polyurethane foams can be used to make articles, particularly for use in commercial decorative molding applications.

Abstract: The invention relates to the use of polyethers containing urethane or urea groups as foam stabilizers, obtained by reacting at least one isocyanate with (a) at least one hydrophilic polyether which statistically carries at least one OH and/or NH2 and/or NH function and (b) at least one hydrophobic polyether which statistically carries at least one OH and/or NH2 and/or NH function and optionally (c) further compounds which carry at least one OH and/or NH2 and/or NH function and/or other isocyanate-reactive groups, such as carboxyl or epoxide functions, with the proviso that at least one isocyanate is ?difunctional.

Abstract: Process for making rigid polyurethane or urethane-modified polyisocyanurate foams at an isocyanate index of between 110 and 120 comprising the step of reacting an organic polyisocyanate composition with an isocyanate-reactive composition in the presence of a hydrocarbon as blowing agent wherein the isocyanate-reactive composition contains between 3 and 30 wt % of polyester polyols and between 20 and 50 wt % of polyether polyols derived from aromatic amines, the amounts being calculated on the basis of total isocyanate-reactive compound.

Abstract: The invention presents a new method to prepare biomedical polyurethanes with high tensile and tear strengths. Such polyurethanes are especially interesting for making foams thereof, e.g. as meniscus implants. A new method, applicable to the biomedical polyurethanes, has been found to make such foams, that can be used as scaffolds. This method is based on salt leaching and phase separation.

Abstract: A method for manufacturing a recycled polycarbonate raw material for a flame retardant resin composition from discarded and/or recovered optical discs using a polycarbonate resin as a substrate material, and includes (a) a step to identify if 2,2-bis(4-hydroxyphenyl)propane as a divalent phenol of the polycarbonate resin raw material is polymerized as the sole raw material in the polycarbonate resin as the substrate material of the discarded and/or recovered optical discs and (b) a step to remove impurities by a chemical treatment by separating only the discarded and/or recovered optical discs, wherein the polycarbonate resin is identified as polymerized by using 2,2-bis(4-hydroxyphenyl)propane as the sole raw material.

Abstract: The present invention is directed to a process for preparing water-blown rigid polyurethane foams having at least an 80% closed-cell content which involves reacting a) at least one polyol mixture which is composed of (i) at least one polymer polyol; (ii) at least one polyol having a hydroxyl value within the range of from about 200 to about 800; and (iii) optionally, at least one polyol having a hydroxyl value within the range of from about 25 to about 115; with b) at least one polymeric isocyanate and/or a prepolymer thereof; in the presence of c) optionally, at least one catalyst; d) water; and e) optionally, at least one additive or auxiliary agent. The present invention is also directed to the closed-cell water blown rigid polyurethane foams produced by the process of the present invention. The invention is further directed to a polyurethane-foam forming mixture which is used to produce the water-blown rigid polyurethane foams of the present invention.

Abstract: The invention relates to a process for the production of water-blown, finely cellular rigid foams containing urethane groups and/or isocyanurate groups by the reaction of polyisocyanates with a polyol component in the form of an emulsion. The invention also relates to open-cell polyurethane foams which are foamable in the mould.

Abstract: A composition for making a polyurethane foam includes a non-fugitive tertiary amine urethane catalyst and an aromatic diacid ester diol or substituted carbamate thereof. Foams prepared from the reaction of a polyol and an organic isocyanate in the presence of these ingredients show excellent resistance to deterioration of physical properties upon humid ageing.

Abstract: The present invention provides a low density, semi-rigid polyurethane foam made from the reaction product, at an isocyanate index of from about 100 to about 150, of at least one polyisocyanate and an isocyanate-reactive blend containing from about 15 wt. % to about 55 wt. %, based on the weight of the resin, of a difunctional or greater functionality polyether polyol, from about 3 wt. % to about 19 wt. %, based on the weight of the resin, of at least one polyether tetrol, and from about 7 wt. % to about 39 wt. %, based on the weight of the resin, of at least one non-halogenated polyester polyol in the presence of from about 5 wt. % to about 30 wt. %, based on the weight of the resin, of at least one non-hydroxy functional flame retardant and from about 1 wt. % to about 20 wt.

Abstract: A method for producing a rigid, closed-cell polyurethane foam having a free-rise density of from about 1.3 lbs/ft.3 to about 4 lbs/ft.3 and exhibiting a shrinkage of less than 10%, comprises mixing together an isocyanate, at least one alkyl alkanoate blowing agent and at least one polyol having a hydroxyl number of from about 150 to about 800 and being selected from the group consisting of polyalkoxylated amines, polyalkoxylated ethers, and polyester polyols, to form a reaction mixture that is curable to produce such foam.

Abstract: This invention provides a novel optionally acylated cyclic tetrasaccharide-containing polyurethane derivative and a process for producing the same, and a novel cyclic tetrasaccharide modified polyurethane foam and a simple process for producing the same. Specifically, the present invention provides a polyurethane derivative containing an optionally acylated cyclic tetrasaccharide: cyclo{?6)-?-D-glucopyranosyl-(1?3)-?-D-glucopyranosyl-(1?-6)-?-D-glucopyranosyl-(1?3)-?-D-glucopyranosyl-(1?}, a process for producing polyurethane, comprising reacting an acylated cyclic tetrasaccharide and a diol compound with a diisocyanete compound, a process for producing a cyclic tetrasaccharide-containing polyurethane, comprising hydrolyzing the polyurethane, a process for producing a polyurethane foam, comprising reacting polyol with polyisocyanete in the presence of the cyclic tetrasaccharide and foaming the reaction product, and a cyclic tetrasaccharide modified polyurethane foam produced by the production process.

Abstract: A composition for making a polyurethane foam includes a non-fugitive tertiary amine urethane catalyst and an ester alcohol or substituted carbamate thereof. Foams prepared from the reaction of a polyol and an organic isocyanate in the presence of these ingredients show excellent resistance to deterioration of physical properties upon humid ageing.

Abstract: A polyurethane foam is obtained by reacting raw materials containing a polyisocyanate, a polyol, a water-absorbency-imparting agent, a catalyst, and a blowing agent, foaming the reaction mixture, and curing the foamed product. The polyol is a polyester polyol. The water-absorbency-imparting agent is a polyoxyalkylene compound having a molecular weight of 100 to 1000 and having a hydroxy group at an end of the molecular chain, or an alcohol with 1 to 8 carbon atoms. The amount of the water-absorbency-imparting agent is from 0.5 to 8 parts by mass per 100 parts by mass of the polyester polyol. The polyisocyanate is an aliphatic polyisocyanate, an alicyclic polyisocyanate, or an aromatic polyisocyanate in which the isocyanate groups are not directly attached to an aromatic ring. The foam has a water absorption ratio of 10 to 30 and a color difference ?YI of 7 or less. The time required until water dropped onto a surface of the foam is completely absorbed into the foam is 20 seconds or less.

Abstract: A polyurethane molding is composed of at least two different polyurethane materials, namely of a polyurethane gel and a polyurethane foam. The foam and the gel are arranged in layers one above another so that both materials act together as spring or damping element with respect to a load in the transverse direction. These moldings may preferably be used as seat cushions.

Abstract: The polishing pad is suitable for planarizing at least one of semiconductor, optical and magnetic substrates. The polishing pad includes a cast polyurethane polymeric material formed with an isocyanate-terminated reaction product formed from a prepolymer reaction of a prepolymer polyol and a polyfunctional isocyanate. The isocyanate-terminated section product has 4.5 to 8.7 weight percent unreacted NCO; and the isocyanate-terminated reaction product is cured with a curative agent selected from the group comprising curative polyamines, curative polyols, curative alcoholamines and mixtures thereof. The polishing pad contains at least 0.1 volume percent filler or porosity.

Abstract: A process for preparing hydrophobic polyols that includes reacting A) a mixture having an OH content of from 180 to 300 mg KOH/g, a viscosity at 23° C. of from 5000 to 20 000 mPas and an OH functionality of from 2.8 to 4.5 including from 5 to 20 wt. % of 3-pentadecadienylphenol, from 5 to 10 wt. % of 3-pentadecadienyl-recorcinol and from 1 to 5 wt. % of 2-methyl 3-pentadecadienylrecorcinol; with B) alkylene oxides (AO) with addition of the AO monomers onto the AO-reactive groups of component A); the ratio of the amounts of A) to B) being from 1:9 to 9:1; where the hydrophobic polyols have an OH number of from 140 to 220 mg KOH/g and a viscosity at 23° C. of from 1000 to 4000 mPas. The hydrophobic polyols can be used in polyurethane systems, in coatings, adhesive bonds, sealants or moulding compounds, which can be used to coat substrates.

Abstract: The invention relates to isocyanate adducts which can be prepared by reacting at least one polyisocyanate with compounds having at least two hydrogen atoms which are reactive toward isocyanate groups and have a crystalline content of less than 10 J/g determined by differential scanning calorimetry in accordance with DIN 51 004 at 20 K/min from room temperature to 250° C. using a nitrogen flow of 3 l/h as carrier gas and an aromatics content reported as carbon atoms in aromatic rings of less than 31% by weight, based on the total weight of the isocyanate adducts.

Abstract: The present invention relates to polyol compositions which can be used to produce dimensionally stable, low density water-blown rigid foams which have acceptable compressive strengths and acceptable k-factors. In one embodiment of the present invention, the polyol compositions are composed of at least one aromatic amine-initiated polyether polyol and at least one polyether polyol having a functionality greater than or equal to 2.5 in which at least 50% by weight of the polyol composition is aromatic amine-initiated polyether polyol and in which no more than 50% by weight of the polyol composition is polyether polyol having a functionality greater than or equal to 2.5.

Abstract: The present invention relates to a process for producing a synthetic resin foam which comprises reacting at least one polyol with at least one polyisocyanate compound in the presence of an organic blowing agent, wherein the organic blowing agent is a blowing agent for synthetic resin foams which is characterized by being a mixture comprising 1,1,1,3,3-pentafluorobutane (HFC-365mfc) and at least one halogen-containing compound and optionally containing at least one member selected from the group consisting of glycol compounds and amide compounds. Also provided are: a premix comprising the blowing agent and a polyol mixture; and a process for producing a synthetic resin foam from these.

Abstract: Process for the preparation of foamed thermoplastic polyurethanes characterized in that the foaming of the thermoplastic polyurethane is carried out in the presence of thermally expandable microspheres.

Abstract: A method for making a rigid polyurethane foam by reacting a polyisocyanate and a polyol in the presence of a urethane catalyst, a blowing agent and a silicone surfactant characterized by employing a blowing agent comprising a C4 or C5 hydrocarbon, or mixtures thereof, with an average molecular weight of ?72 g/mole and a boiling point in the range of 27.8 to 50° C., and a silicone surfactant comprising a polyether-polysiloxane copolymer represented by the following formula: (CH3)3—Si—O—(Si(CH3)2—O)x—(Si(CH3)(R)O)y—Si(CH3)3 where R=(CH2)3—O—(—CH2—CH2—O)a—(CH2—CH(CH3)—O)b—R?, and where R? is H, (CH2)zCH3, or C(O)CH3; x+y+2 is 60–130; x/y is 5–14; z is 0–4; the total surfactant molecular weight, based on the formula, is 7000–30,000 g/mole, the wt % siloxane in the surfactant is 32–70 wt %, the blend average molecular weight (BAMW) of the polyether portion is 450–1000 g/mole, and the mole % of ethylene oxide in the polyether portion is 70–100 mole %.

Abstract: A composition and a method for producing primarily water blown polyurethane foams is provided. The composition uses isocyanate ratios greater than conventional foam system to provide a water blown polyurethane foam suitable for a wide variety of applications including spray roofing, insulation, etc. The preferred composition for preparing a polyurethane foam comprises an isocyanate component and a polyol component, wherein the polyol component preferably comprises a combination of Mannich polyol, polyester polyol, and polyether polyol. Preferably, the composition includes water to act as a blowing agent and a metal salt catalyst to assist in the reaction. Preferably, the isocyanate index is between about 1.2 and about 2.0. Additional catalysts, surfactants, flame retardants, and blowing agents may also be used depending upon the desired finished product.

Abstract: The invention relates to flame resistant rigid foams and formulations useful for the production thereof. The polyol formulation must include at least one substance which is inert with respect to isocyanates, does not deplete the ozone layer and has a boiling point below 55° C. and a reaction product of at least one compound with an aromatic ring, at least one aldehyde or ketone and at least one primary or secondary amine. This polyol formulation is reacted with an isocyanate, optionally with other commonly used additives, to produce rigid flame resistant foams.

Abstract: The present invention generally includes material comprising the reaction product of an A-side comprising an isocyanate and a B-side comprising a crosslinker, a catalyst, and a modified vegetable oil. The present invention also generally includes a material comprising the reaction product of an A-side comprising an isocyanate and a B-side comprising an oxylation compound, a modified vegetable oil, and a catalyst.

Abstract: Disclosed is a composition for preparing a rigid polyurethane foam having a good demolding property by defining polyol component and catalyst component. The polyol component comprises 40˜60 wt. % of polyol obtained by polymerization with an organic oxide using sorbitol as an initiator, 5˜10 wt. % of polyol obtained by polymerization with an organic oxide using ethylene diamine as an initiator, 20˜30 wt. % of polyol obtained by polymerization with an organic oxide using toluene diamine or toluene diamine and triethanol amine as a single or a complex initiator, and, optionally, 5˜20 wt. % of multivalent polyol of an ester structure, and the catalyst component is chosen in a group comprising a foaming catalyst, a gelling catalyst, a trimerization catalyst, a mixed form of the foaming catalyst and the gelling catalyst, and compound thereof.

Abstract: A static dissipative flexible polyurethane foam is formed under free rise expansion conditions from a polyether graft polyol and an isocyanate, wherein one or more anti-static additives are incorporated into the reaction mix in an amount from 0.10 to 20 parts by weight. Water is added in an amount of from 0.2 to 1.0 parts per weight. Upon curing, the foam has a density in the range of 6 to 20 pounds per cubic foot, a surface resistivity below 1×1011 ohms/square, and a pore size in the range of 100 to 250 pores per inch. The foam may be fabricated (cut or shaped) to form a shaped article, such as a roller, a clean room wipe, a cosmetic applicator or a packaging element.

Abstract: A process for preparing oil and petroleum-resistant cellular to solid (polyurea)polyurethanes (PURS) with improved physical properties in which a polyether polyol component having a number average molecular weight of from 1000 to 8000 and a polyester polyol component having a number average molecular weight of from 1000 to 6000 are reacted with a polyisocyanate and the (polyurea) polyurethanes produced by that process. The (polyurea)polyurethanes are particularly useful for personal safety equipment and in the construction of automobiles.

Abstract: The present invention relates to a preparation method for low-density polyurethane foam excelling in the flame retardance and the dimensional stability, wherein rigid polyurethane foam having the average value for the ratio of lengthwise direction diameter/cross direction diameter of cells being 1.0 to 1.4 and the density of 20 to 40 kg/m3 is prepared by combining, as blowing agent, carbon dioxide generated in the reaction between water and polyisocyanate and carbon dioxide under supercritical state, subcritical state or liquid state, and by adding said water and said carbon dioxide under liquid state into said polyol component prior to mixing the polyisocyanate component and the polyol component, and to rigid polyurethane foam obtained by said method.

Abstract: Single component compositions for making a moisture-cured polyurethane foam are disclosed. Foam produced from the compositions of the present invention produce very low foaming pressure due to their 60-95 percent open-cell content. After these compositions are applied and cure, they form a permanent seal around the perimeter of installed fenestration products.

Abstract: A process for producing a polyurethane foam which comprises mixing a polyol solution comprising 100 parts by weight of a polyester-polyol, 0.1 to 1.8 parts by weight of water and 0.1 to 5 parts by weight of urea, and a catalyst with a polyisocyanate compound and foaming the mixture. According to the process, there can be produced a polyurethane foam which satisfies both productivity and moldability even when having a low density, and is suitable for use in shoe soles.

Abstract: A thermoformable polyurethane foam having excellent compression set resistance, and a thermoformable polyurethane foam having excellent compression set resistance and shape retention under load. In another embodiment, at least one additional layer of a polyurethane foam is integrally bonded to the thermoformable foam. A moisture management system for polyurethane foams is also described. The foams have particular utility as shoe sole inserts.

Abstract: Raw materials for anti-cracking polyurethane foams comprises: a mixed polyol 100 weight parts; an isocyanate 140˜180 weight parts; a catalyst 1.0˜3.0 weight parts; water 1˜2.5 weight parts; a foam blowing agent 30.0˜35.0 weight parts; and an additive 1.0˜3.0 weight parts, and a preparation method thereof.

Abstract: A process is disclosed for producing resilient polyurethane foams by foaming an organic polyisocyanate, an iso-cyanate-reactive compound and a fusible polymer. The improvement in the hardness of the foams is achieved without adversely affecting the other properties of the foams, such as tensile strength and elongation.

Abstract: In the process of the present invention, an organic polyisocyanate is reacted with a sorbitol-based polyether polyol having a number average molecular weight of from about 400 to about 1500, in the presence of a pentafluoropropane blowing agent, and a catalyst.

Abstract: The present invention is directed to a process for preparing water-blown rigid polyurethane foams having at least an 80% closed-cell content which involves reacting a) at least one polyol mixture which is composed of (i) at least one polymer polyol; (ii) at least one polyol having a hydroxyl value within the range of from about 200 to about 800; and (iii) optionally, at least one polyol having a hydroxyl value within the range of from about 25 to about 115; with b) at least one polymeric isocyanate and/or a prepolymer thereof; in the presence of c) optionally, at least one catalyst; d) water; and e) optionally, at least one additive or auxiliary agent. The present invention is also directed to the closed-cell water blown rigid polyurethane foams produced by the process of the present invention. The invention is further directed to a polyurethane-foam forming mixture which is used to produce the water-blown rigid polyurethane foams of the present invention.