Abstract: The polyisocyanate polyaddition products comprise hydrophobic compounds plus at least one further compound selected from the group consisting of: (i) organic, cyclic compounds having a molecular weight of from 200 to 3000 g/mol, (ii) salts of metals of transition groups I, II and/or VIII, (iii) organic and/or inorganic acid anhydrides, (iv) cyclic sulfonic esters and/or sulfones, (v) lactones, lactams and/or cyclic esters and/or (vi) &agr;,&bgr;-unsaturated carboxylic acids, &agr;,&bgr;-unsaturated carboxylic acid derivatives, &agr;,&bgr;-unsaturated ketones and/or &agr;,&bgr;-unsaturated aldehydes.

Abstract: The invention is directed to a novel biomedical polyurethane based on diisocyanatae linked polyester polymer and diol components, said diol component having a uniform block-length.

Abstract: A process for preparing a polyurethane foam, comprising reacting a polyol having a number-average molecular weight of not less than 1000 and less than 2500 with a polyisocyante compound in the presence of a catalyst and a blowing agent in a mold, to give a molded article having a density of 0.4 to 0.8 g/cm3, and heating the resulting molded article to a temperature of 60° to 100° C. The polyurethane foam is used as a cushioning material such as shoe soles of sports shoes.

Abstract: Semiflexible and flexible polyurethane foams having significantly reduced fogging and improved physical properties such as tensile strength, useful in the transportation industry, are obtained from a polyurethane foam-forming reaction-mixture containing as a polyester polyol for the foam a polyester polyol substantially free of any ether components which comprising: (a) at least one polyfunctional carboxylic acid and/or carboxylic anhydride compound; (b) at least one linear polyhydric alcohol; and (c) at least one branched polyhydric alcohol wherein the reactants of the polyester polyol are selected such that they cannot combine to provide a cyclic ester comprising a 12 to 14 membered ring. Optionally, the polyester polyol can further contain (d) a branched polyol having a functionality of at least three.

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, a methyl formate 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: The invention concerns a method for making a polyurethane foam by reacting at least a polyester polyol with at least a polyisocyanate in the presence of a foaming agent and a catalytic agent, such a polyester polyol having been previously obtained by reacting a reactive acid A comprising at least an aliphatic or aromatic polyacid with functionality not less than 2 with at least a polyol P2 with functionality equal to 2 and at least an aliphatic or aromatic polyacid with functionality not less than 2 with at least a polyol P2 with functionality equal to 2 and at least a polyol P3 with functionality not less than 3, being thereafter called AP2P3, wherein the catalytic agent at least partly consists of at least one amine polyester polyol AP2P3, wherein at least part of polyol P3 consists of at least a polyoxyalkylene polyalkanolamine having at least a tertiary amine function, the alkanol radicals of said polyalkanolamine being C1-C6, the alkylene oxide units being C2-C4 and the statistical mean of the number N o

Abstract: A solid and/or cellular polyurethane elastomers which are produced using polyester polyols are disclosed. The elastomers which exhibit improved stability to hydrolysis are characterized in that their preparation is carried out in the presence of at least one esters of monobasic carboxylic acid or polybasic carboxylic acids, the (first) dissociation constant (pK) of which is 0.5 to 4.

Abstract: A polyol composition containing a polyester polyol, at least 5 weight % of a compatibilizing agent, based on the weight of the polyol and compatibilizing agent, and a hydrocarbon blowing agent. The compatibilizing agent is one or a combination of a benzoate glycol adduct, a substituted benzoate glycol adduct, a naphthenate glycol adduct, a substituted naphthenate glycol adduct, a toluate glycol adduct, or a substituted toluate glycol adduct. The hydrocarbon blowing agent is selected from cyclopentane, isopentane, n-pentane, 2-chloropropane; 1,1,1,2-tetrafluoroethane (HFC-134a); 1,1,1,3,3-pentafluoropropane (HFC-245fa); and n-propylbromide, or mixtures thereof. The compatibilizing agent improves the miscibility of conventional polyester polyols with hydrocarbon blowing agents. The polyol composition can be reacted with a polyisocyanate to form a foam.

Abstract: A two-component on-site foam system for producing an intumescing fire protection foam is described with a density of less than 200 kg/m3 and an increased fire resistance endurance, with a polyol component (A), which contains at least one polyol, one catalyst for the reaction between the polyol and the polyisocyanate, water or a blowing agent based on a compressed or liquefied gas as foam-forming agent and at least one intumescing material based on an acid-forming agent, a carbon-supplying compound and a gas-forming agent, and a polyisocyanate component (B), which contains at least one polyisocyanate, wherein the polyol component (A) contains at least one polyester polyol, at least one aminopolyol, at least one halogen-containing polyol, at least one acid-forming agent, expanding graphite and at least one ash crust stabilizer, the quantitative ratios of the polyols to the polyisocyanate or polyisocyanates being matched so that, when the polyol component (A) is mixed with the polyisocyanate component (B) as spe

Abstract: Polyurethane foams are prepared by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms reactive with isocyanate groups, by a process in which the polyisocyanates a) are aliphatic di- or polyisocyanates and the compounds having at least two hydrogen atoms reactive with isocyanate groups b) contain at least one acrylate polyol.

Abstract: To provide a method for producing polyester polyol that can provide a simple process to produce extensively improved production efficiencies and also produce the polyester polyol of stable in quality, an apparatus for producing the polyester polyol produced by the method, a polyester polyol produced by the method, and a polyurethane foam obtained by use of the polyester polyol produced by the method, polyethylene terephthalate and raw polyol are allowed to react in a reaction vessel to produce polyester polyol and also ethylene glycol which is a by-product of the reaction is distilled off and the distillate is modified in a modifying vessel so that it can have a predetermined hydroxyl value and then is fed to the reaction vessel again as the raw glycol, to thereby produce the polyester polyol.

Abstract: A composition useful as a blowing agent having no flash point or reduced combustibility comprising 2-chloropropane and a gas selected from the group consisting of a fluorohydrocarbon, perfluorocarbons, fluoroethers, hydrofluoropolyethers and mixtures thereof is disclosed. A polyisocyanurate foam or a polyurethane modified polyisocyanurate foam having a mainly closed cell structure and also a method for preparing this foam, the latter comprising closed cells wherein a foam blowing agent consisting of a mixture of 2-chloropropane and one or more HFC compounds including pentafluoropropane, pentafluorobutane, heptafluoropropane, hexafluoropropane or pentafluoroethane are disclosed. Pentanes can be added if desired. Azeotropic mixtures in which 2-chloropropane is an ingredient are disclosed.

Abstract: This invention relates to flame-laminable polyurethane block foams having high peel strength, a process for their production and the use thereof for textile lamination.

Abstract: Rigid foams having excellent compression strength, dimensional stability, flame retardance and adhesion are produced by reacting an active hydrogen compound having at least two functionalities with a polyisocyanate compound in the presence of a catalyst and a blowing agent comprising either water alone or a mixture of water and a low boiling compound, wherein (1) the polyisocyanate compound is a prepolymer obtained by reacting a polymeric MDI with 5 to 30% by weight, based on the polymeric MDI, of a polyether polyol and/or polyester polyol having a hydroxyl value of at most 100 mg KOH/g, and (2) the number of isocyanate groups in the polyisocyanate compound is at least 1.5 times by mole as large as the number of active hydrogen atoms in the active hydrogen compound and water.

Abstract: A process for producing a rigid polyurethane foam provides a rigid polyurethane foam having a closed-cell size of about 80-130 &mgr;m and thus, improved heat insulating properties.

Abstract: This invention relates to flame-laminable polyurethane block foams having high peel strength, a process for their production and the use thereof for textile lamination.

Abstract: The present invention relates to polyol mixtures which are suitable for the preparation of rigid polyurethane foams and comprise addition products of alkylene oxide on aromatic di- or polyamines, and rigid foams prepared with these polyol mixtures.

Abstract: Disclosed are polyester-ether polyols and their use in urethane prepolymers, urethane foams and non-foam urethane coatings, adhesives, sealants and/or elastomers. Methods for producing such polyester-ether polyols are disclosed, along with methods for producing urethane prepolymers. The polyester-ether polyols of the instant invention are preferably the reaction product of phthalic anhydride, diethylene glycol, and propylene oxide. These polyester-ether polyols are useful as either the primary polyol in urethane compositions or in combination with conventional auxiliary polyester- and/or polyether-based polyols. The polyester-ether polyols impart greatly improved solubility and compatibility to mixtures of either polyether and/or polyester polyols. The polyester-ether polyols of the instant invention are desirably of lower viscosity than their precursor intermediate polyester polyols and are generally soluble in either polyester- and/or polyether-based polyols.

Abstract: Compositions for the formation of temperature resistant, tough, flame retardant polyurethane foams, comprising a low VOC polyisocyanate component wherein the isocyanate is a low functionality isocyanate; a low VOC active-hydrogen containing component substantially reactive with the low functionality isocyanate to form a polyurethane; a surfactant composition; and a catalyst component, wherein the total mass loss of the foam is less than 1% by weight as measured by ASTM E595. The foams are useful as gasketing materials, for example.

Abstract: The invention relates to novel titanium/zirconium catalysts, and to a process for the preparation of these titanium/zirconium catalysts. The process comprises reacting orthoesters or condensed orthoesters of titanium and/or zirconium, with one or more polyalcohols. Suitable polyalcohols comprise those compounds having at least two hydroxyl groups and a number average molecular weight of at least 180 g/mol. The invention also relates to a process for preparing (poly)esters from these novel catalysts, which exhibit little discoloration and are suitable to be used as a reaction component in the preparation of polyurethane (PUR) foams.

Abstract: Provided are catalyst systems which produce flexible polyurethane polyester foams that are color stable, are lower in odor, and uses less catalysts than current most commonly practiced technology. The use of lower amounts of catalysts with low vapor pressure reduces worker exposure to alkaline corrosive materials, reduces pollution through less pounds of volatile organic chemicals (VOC's) and is less expensive.

Abstract: Safety clothing is produced by molding polyether-based plastic-forming compositions. Particularly preferred articles of safety clothing produced by this process are safety shoe soles.

Abstract: The polyisocyanate polyaddition products comprise hydrophobic compounds plus at least one further compound selected from the group consisting of: (i) organic, cyclic compounds having a molecular weight of from 200 to 3000 g/mol, (ii) salts of metals of transition groups I, II and/or VIII, (iii) organic and/or inorganic acid anhydrides, (iv) cyclic sulfonic esters and/or sulfones, (v) lactones, lactams and/or cyclic esters and/or (vi) &agr;,&bgr;-unsaturated carboxylic acids, &agr;,&bgr;-unsaturated carboxylic acid derivatives, &agr;,&bgr;-unsaturated ketones and/or &agr;,&bgr;-unsaturated aldehydes.

Abstract: The disclosed invention relates to a polyurethane elastomer that has improved hydrolysis resistance. The polyurethane elastomer is made by reacting a polyol blend of an aromatic dicarboxylic acid based polyester polyol, an aliphatic dicarboxylic acid based polyester polyol, and a blowing agent. The polyol blend is reacted with an isocyanate terminated prepolymer. The aromatic dicarboxylic acid based polyester polyol is the reaction product of an aliphatic alcohol and ortho-phthalic acid. The aliphatic dicarboxylic acid based polyester polyol is the reaction product of adipic acid and glycols.

Abstract: The present invention discloses a phase stable polyol blend composition containing a sucrose and dipropylene glycol co-initiated propylene oxide polyether polyol, a polyester polyol, a compatibilizing agent and a hydrocarbon blowing agent. The polyester polyol is preferably a phthalic anhydride-initiated polyester polyol. The compatibilizing agent is a butanol-initiated propylene oxide polyether surfactant.

Abstract: The present invention discloses a polyol resin composition containing a polyether polyol blend, a polyester polyol, and a hydrocarbon blowing agent. The polyether polyol blend has at least a diamine initiated polyol, a propylene oxide polyol, and a polyethylene terephthalate initiated polyol having a functionality of from 2.3 to 3.0. The polyester polyol is preferably a phthalic anhydride initiated polyester polyol. The blowing agent is a C4-C6 hydrocarbon. Also disclosed is a method of producing a polyurethane foam combining the above mentioned polyol resin and an isocyanate component.

Abstract: The present invention discloses a phase stable polyol blend composition containing a sucrose and dipropylene glycol co-initiated propylene oxide polyether polyol, a polyester polyol, a compatibilizing agent and a hydrocarbon blowing agent. The polyester polyol is preferably a phthalic anhydride-initiated polyester polyol. The compatibilizing agent is a butanol-initiated propylene oxide polyether surfactant.

Abstract: The present invention provides a gripping part such as a steering wheel and a grip, having a soft feeling equivalent to a RIM urethane and excellent sweat resistance, without the need of coating, which solves problems involved in RIM urethane steering wheels and grips including low productivity, low recycling property, and the like. That is, a gripping part comprising a foamed product of a thermoplastic elastomer with a 1.1 to 8.0 times expansion ratio, wherein the thermoplastic elastomer is a polyurethane elastomer comprises a specific polymer polyol, a polyisocyanate, and as needed, a chain extending agent reactive with the polyisocyanate.

Abstract: A sponge including an elastic material having a lipid, such as an oil, a fat, or a combination thereof, integrally formed therewith. The elastic material includes an amount from between 0.5 to 20 parts by weight of the lipid, and the lipid is selected from the group consisting of esters of fatty acids, alkanes, squalane and derivatives thereof squalene, bisabolol, animal hair oils and fats, wax, lanolin and combinations thereof to provide the sponge with a gentle feel. The sponge may also be made by first foam molding the sponge from an elastic material, impregnating the sponge with a water-dispersed lipid and allowing the sponge to dry for a predetermined amount of time so that the lipid is substantially inseparable from the elastic material.

Abstract: A polyester polyol composition comprising a phthalic anhydride-initiated polyester polyol, a C4-C6 hydrocarbon blowing agent, and an oxyethylated fatty acid or fatty alcohol compatibilizing agent having an HLB of from about 7 to about 12. 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: The invention relates to a foamable composition comprising at least two parts. The first part comprises a polyol, a thixotropic gelling agent, a blowing agent, a urethane reaction catalyst and a isocyanurate reaction catalyst. The second part comprises at least one isocyanate. A foam mass can be prepared by combining the first part polyol component with the second part isocyanate component. The composition is foamable under water and exhibits, upon foaming under water, substantially the same wet foam density and dry foam density. The invention also relates to a method of repairing or reinforcing structural members having defects such as spike holes left after spike removal from railroad ties during road bed maintenance or repair by means of the foamable composition.

Abstract: A polyurethane foam which is obtained by reacting an addition-polymerizable active hydrogen component comprising a compound having a group containing active hydrogen and an addition-polymerizable functional group or comprising both this compound and a compound containing at least 2.5 groups (on the average) containing active hydrogen and not containing addition-polymerizable functional groups with an organic polyisocyanate in the presence or absence of at least one auxiliary selected from the group consisting of foaming agents and additives to polymerize the addition-polymerizable functional group and simultaneously form a polyurethane, and which has a structure in which the chains formed by the addition polymerization have been cross-linked to the polyurethane chains. The polyurethane foam is useful as a rigid polyurethane foam excellent in hardness, dimensional stability, etc. and usable as a heat insulator, shock-absorbing material, synthetic wood, etc.

Abstract: A composite polyurethane foam structure and method of preparing the composite structure, which structure includes a semirigid-rigid polyurethane foam layer having bonded, free, unreacted, ethylenically unsaturated groups like allyl or acrylic groups. The structure includes a cured, unsaturated resin composition layer which is chemically bonded to one or both surfaces of the polyurethane foam layer through the polymerization of the allyl or acrylic group in the foam surface with the polyester resin composition.

Abstract: A polyol solution containing one or a combination of a benzoate glycol adduct, a substituted benzoate glycol adduct, a napthenate glycol adduct, a substituted naphthenate glycol adduct, a toluate glycol adduct, or a substituted toluate glycol adduct, and a closed cell, rigid polymer foam formed as a reaction product of the polyol solution, which foam comprises the reaction product of a polyisocyanate and an isocyanate-reactive component in the presence of a catalyst and a hydrogen-containing blowing agent or mixture of hydrogen-containing blowing agents, wherein the isocyanate-reactive component comprises a mixture of a hydroxy terminated polyester and a polyester comprised of the benzoic acid glycol adduct, toluic acid glycol adduct, or napthoic acid glycol adduct Foams prepared from the mixture have superior thermal conductivity, lower flammability, and higher stability of the emulsified liquid reactants prior to polymerization.

Abstract: Rigid foam excellent in compression strength, dimensional stability, flame retardancy and adhesion is produced.

Abstract: The invention relates to novel titanium/zirconium catalysts, and to a process for the preparation of these titanium/zirconium catalysts. The process comprises reacting orthoesters or condensed orthoesters of titanium and/or zirconium, with one or more polyalcohols. Suitable polyalcohols comprise those compounds having at least two hydroxyl groups and a number average molecular weight of at least 180 g/mol. The invention also relates to a process for preparing (poly)esters from these novel catalysts, which exhibit little discoloration and are suitable to be used as a reaction component in the preparation of polyurethane (PUR) foams.

Abstract: A process for preparing hydrocarbon blown rigid polyurethane foam using a novel compatibilizing agent. The compatibilizing agent is an alkoxylate adduct of a triglyceride with a hydroxyl value of about 100 or less. The triglyceride adduct has an ethylene oxide content of at least 40% by weight thereof. These adducts may be used alone or in mixture with other compatibilizers. The compatibilizers increase the stability of rigid foam formulation emulsions containing greatly increased hydrocarbon blowing agent levels while showing little or no adverse affect to physical properties of foams prepared therewith.

Abstract: Polyurethanes synthesized from sorbitol-branched polyester made by esterification of a diacid (or anhydride thereof diol, and sorbitol (or mixtures of same with other polyols).

Abstract: A polyurethane foam which is obtained by reacting an addition-polymerizable active hydrogen component comprising a compound having a group containing active hydrogen and an addition-polymerizable functional group or comprising both this compound and a compound containing at least 2.5 groups (on the average) containing active hydrogen and not containing addition-polymerizable functional groups with an organic polyisocyanate in the presence or absence of at least one auxiliary selected from the group consisting of foaming agents and additives to polymerize the addition-polymerizable functional group and simultaneously form a polyurethane, and which has a structure in which the chains formed by the addition polymerization have been cross-linked to the polyurethane chains. The polyurethane foam is useful as a rigid polyurethane foam excellent in hardness, dimensional stability, etc. and usable as a heat insulator, shock-absorbing material, synthetic wood, etc.

Abstract: Rigid polyurethane foams having improved flame resistance are disclosed. The foams are prepared from a composition containing (a) an isocyanate, (b) an isocyanate reactive composition containing an aromatic polyester polyol, (c) an organo phosphorus compound and (d) a C1 to C4 hydrofluorocarbon.

Abstract: To provide a method for producing polyester polyol that can provide a simple process to produce extensively improved production efficiencies and also produce the polyester polyol of stable in quality, an apparatus for producing the polyester polyol produced by the method, a polyester polyol produced by the method, and a polyurethane foam obtained by use of the polyester polyol produced by the method, polyethylene terephthalate and raw polyol are allowed to react in a reaction vessel to produce polyester polyol and also ethylene glycol which is a by-product of the reaction is distilled off and the distillate is modified in a modifying vessel so that it can have a predetermined hydroxyl value and then is fed to the reaction vessel again as the raw glycol, to thereby produce the polyester polyol.

Abstract: Described is an NCO-group-containing polyurethane prepolymer madefrom polyisocanyates and polyols derived from natural oils. The invention is characterized in that the polyol is obtained by transesterification in the presence of basic lithium compounds. Together with a tertiary amine used to accelerate the moisture curing, the storage stability is thus increased considerably. Up to 4.0 mmol of the lithium compound is used per kilogram of polyol, and 0.1 to 2.0% by wt. of the amine, relative to the total weight of the composition, is used as the accelerator. The polyurethane prepolymer is suitable not only for the production of adhesives but also for the production of foamed materials, in particular those dispensed from throw-away pressure vessels.

Abstract: The present invention provides a flexible polyurethane foam having good resistance to wet heat aging and resistance to ozone deterioration and a speaker edge having an excellent waterproofness comprising such a flexible polyurethane foam. As a polyol, a polyol component obtained by mixing a polyester polyol having an excellent compatibility with polyether polyol such as adipate of a long-chain alkylene glycol having at least 5 carbon atoms with a foaming agent, a catalyst, a foam stabilizer, etc. is reacted with a polyisocyanate to obtain a flexible polyurethane foam having good resistance to wet heat aging and resistance to ozone deterioration. Further, the incorporation of a specific aromatic secondary amine compound, a monofunctionally-terminated compound and an ultraviolet absorbent in the foam composition makes it possible to obtain a flexible foam having better resistance to ozone deterioration and weather resistance.

Abstract: A process for preparing a polyurethane foam, comprising reacting a polyol having a number-average molecular weight of not less than 1000 and less than 2500 with a polyisocyanate compound in the presence of a catalyst and a blowing agent in a mold, to give a molded article having a density of 0.4 to 0.8 g/cm3, and heating the resulting molded article to a temperature of 60° to 100° C. The polyurethane foam is used as a cushioning material such as shoe soles of sports shoes.

Abstract: Rigid polyurethane foams having improved flame resistance are disclosed. The foams are prepared from a composition containing (a) an isocyanate, (b) an isocyanate reactive composition containing an aromatic polyester polyol, (c) an organo phosphorus compound and (d) a C1 to C4 hydrofluorocarbon.

Abstract: The present invention provides a flexible polyurethane foam having good resistance to wet heat aging and resistance to ozone deterioration and a speaker edge having an excellent waterproofness comprising such a flexible polyurethane foam. As a polyol, a polyol component obtained by mixing a polyester polyol having an excellent compatibility with polyether polyol such as adipate of a long-chain alkylene glycol having at least 5 carbon atoms with a foaming agent, a catalyst, a foam stabilizer, etc. is reacted with a polyisocyanate to obtain a flexible polyurethane foam having good resistance to wet heat aging and resistance to ozone deterioration. Further, the incorporation of a specific aromatic secondary amine compound, a monofunctionally-terminated compound and an ultraviolet absorbent in the foam composition makes it possible to obtain a flexible foam having better resistance to ozone deterioration and weather resistance.

Abstract: This invention relates to a foamable composition comprising at least two parts. More specifically, the first part comprises at least one polyol, at least one gelling agent, and at least one blowing agent wherein the first part comprises an effective amount of hydrophobic ingredients and a second part comprising at least one isocyanate. A foam mass can be prepared by a method of combining a polyol component with an isocyanate component substantially free of urethane prepolymer and applying the mixture to a void or substrate. The invention also relates to methods of using certain polyurethane compositions in the repair of surface defects or for the reinforcement of structural members such as spike holes left after spike removal from railroad ties during road bed maintenance or repair. This invention further relates to a method of foaming certain polyurethane compositions in the presence of water.

Abstract: A polyester-polyol being liquid at 40° C. and having a viscosity of not more than 10,000 mPa·s at 60° C., prepared by polycondensation of an acid component including at least one phthalic acid component selected from phthalic anhydride and o-phthalic acid, and an aliphatic polybasic acid, with a polyhydric alcohol; a process for preparing a polyurethane foam including reacting a polyisocyanate component with a polyol component including the polyester-polyol; a process for preparing an isocyanate prepolymer from a polyisocyanate component and a polyol component including the polyester-polyol; and a process for preparing a polyurethane foam including reacting an isocyanate prepolymer prepared from a polyisocyanate component and a polyol component including the polyester-polyol, with a polyol component. The resulting polyurethane foam shows remarkably improved physical properties such as tensile strength and tear strength, while having low density, acceptable appearance and texture.

Abstract: A process for producing a rigid foam based on isocyanate comprises reacting an organic and/or modified organic polyisocyanate with a polyol composition 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 polyol composition comprises a phthalic anhydride-initiated polyester polyol, a blowing agent comprising 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: The invention provides a liquid polyisocyanate prepolymer composition which is a result of combining about 50.0 to 90.0 percent by weight of an isocyanate blend (a.) having 55.0 to 75.0 weight percent 4,4′-MDI, 17.0 to 27.0 weight percent 2,4′-MDI, 1.0 to 10.0 weight percent 3-ring MDI oligomer, and 1.0 to 15.0 weight percent n-ring MDI oligomer (n greater than 3); about 5.0 to 30.0 weight percent of a polyhydroxy containing polyol (b.) having a molecular weight of from 700 to about 6,000; and about 15.0 to 75.0 weight percent of a toluene diisocyanate (c.). The resulting isocyanate prepolymer composition has a free NCO content of from about 30.0 to 45.0 weight percent and particularly desirable flow characteristics. The invention further provides a method of making an isocyanate prepolymer composition, a process of making a polyurethane foam utilizing the isocyanate prepolymer composition of the invention, and polyurethane foams produced by the disclosed process.