Abstract: The invention pertains to drip retardant flexible polyurethane foams prepared by the reaction of an isocyanate with a polyol resin containing a drip retardant made of either a trialkyl end-capped amine functional silicone polymer or a trialkyl end-capped carbinol functional silicone polymer to effectively prevent the foam from dripping while burning and encourage char formation.

Abstract: Novel polyurethane-urea foams having superior tear and tensile strengths, elongation and load-bearing are prepared by reacting an alkylthio-substituted aromatic diamine in a mixture of polyols with an aromatic diisocyanate or aromatic diisocyanate prepolymer or mixtures thereof, having free NCO content of 0.1-50% by weight. These foams have good dynamic properties that make them attractive as cushioning materials.

Abstract: Novel esters containing bonded fluorocarbon and oxypropylenealkylether groups and of the formula ##STR1## where Rf is straight-chain or branched, partially fluorinated or perfluorinated alkyl of 2 to 10 carbon atoms, partially fluorinated or perfluorinated cycloalkyl of 4 to 8 carbon atoms,perfluorophenyl orperfluoroalkylphenyl where the perfluoroalkyl radical is of 1 to 6 carbon atoms,R is straight-chain or branched alkyl of 1 to 4 carbon atoms andn is an integer from 2 to 70,blowing agent-containing emulsions which have a long shelf life and contain at least one partially fluorinated or perfluorinated (cyclo)aliphatic hydrocarbon of 3 to 8 carbon atoms and/or sulfur hexafluoride, at least one unmodified or modified organic polyisocyanate or a relatively high molecular weight reactive hydrogen compound and at least one of the abovementioned carboxylic or carbamic esters, and the use of these emulsions for the preparation of cellular plastics by the polyisocyanate polyaddition method.

Abstract: A process for the production of an open cell polyurethane foam comprises the mixing of the following components at ambient temperatures in a mixing zone: a diisocyanate having a functionality of at least about 2.0, at least one hydrogen donor, at least one surfactant which is effective in forming an open cell polyurethane foam, at least one catalyst, and a blowing agent comprising a gas having a boiling point below approximately -100.degree. F. at atmospheric pressure which preferably comprises carbon dioxide. In addition, the mixture may also optionally contain water. The mixture is subjected to a pressure in said mixing zone which is sufficient to maintain the blowing agent in the liquid state at ambient temperatures. After mixing, the mixture is ejected from the mixing zone to atmospheric pressure, thereby completely and instantaneously vaporizing the blowing agent to provide expansion of the mixture. The resultant foam is then cured at ambient temperatures.

Abstract: Polyisocyanate composition comprising an organo clay and a cyclic alkylene carbonate. The composition is useful for wood-binding, preparing polyurethanes and rigid and flexible polyurethane foams.

Abstract: This invention relates to a foamed heat insulation material for refrigerators and freezers which makes it possible to reduce the quantity of a fluorocarbon foaming agent used therein. Said foamed heat insulation material is obtained by mixing a carbon dioxide adsorbent prepared by treating the surface of the carbon dioxide absorbent so as to make it hydrophobic with a water-containing premix component and an isocyanate component and stirring the resulting mixture.The foamed heat insulation material thus obtained can reduce the quantity of the fluorocarbon foaming agent at the time of foaming owing to the use of water as a foaming agent, and after the foaming, can adsorb off with the carbon dioxide adsorbent the carbon dioxide generated by the isocyanate-water reaction and thereby purify the gas in foams into a fluorocarbon gas.

Abstract: Hydrocarbon oils having a high aromaticity (at least 85%, preferably 95-100%) and a boiling point of about 342.degree. to about 510.degree. C. (about 650.degree. to about 950.degree. F.) are used as partial or total replacements for the foam stabilizers used in the preparation of both rigid, closed cell polyurethane foams and flexible, open cell polyurethane foams. These oils are useful as a replacement for both silicon surfactants and organic (i.e., non-silicon) surfactants. For certain blowing agents (e.g., trichlorofluoromethane and methylene chloride), hydrocarbon oils having a boiling point range of about 399.degree. to 454.degree. C. (about 750.degree. to about 850.degree. F.) are preferred. Highly aromatic oils having a boiling point of about 281.degree. to about 510.degree. C. are useful for reducing the vapor pressure of toluene diisocyanate and for preventing the low temperature crystallization of toluene diisocyanate or diphenylmethane diisocyanate.

Abstract: A process for producing a high resilience polyurethane foam by reacting a polyol with a polyisocyanate in the presence of a catalyst, a blowing agent, and a foam stabilizer; said polyisocyanate containing at least diphenylmethane diisocyanate and/or a mixture of diphenylmethane diisocyanate with a derivative thereof, the blowing agent being water, or water and a halogenated hydrocarbon in amounts of not less than 2 parts by weight of water and not more than 20 parts by weight of the halogenated hydrocarbon based on 100 parts by weight of the polyol, and the catalyst being at least one selected from the compounds represented by the formula (I) below: ##STR1## where R.sup.1 is alkyl having 1 to 4 carbons, dimethylaminopropyl, benzyl, vinyl, or hydroxyalkyl having 1 to 3 carbons; R.sup.2 is hydrogen, alkyl having 1 to 4 carbons, alkyl, benzyl or phenyl; and R.sup.3 and R.sup.4 are independently hydrogen, alkyl having 1 to 4 carbons, or hydroxymethyl.

Abstract: A modified organic polyisocyanate is prepared in such a manner that a trimerization catalyst, an organic phosphite estr, and a surfactant, and optionally a ferrocene compound are added to an organic isocyanate and/or a partially urethanized organic polyisocyanate to cause isocyanuration in an extent that not more than 20% by weight of entire isocyanate groups are isocyanurated; and a stopper is added, if necessary.

Abstract: A method is disclosed for the preparation of flexible polyester polyurethane foam by reaction of at least difunctional polyesterols with at least difunctional organic isocyanates in the presence of catalysts and a stabilizer mixture of organic and organosilicon compounds, water, optionally blowing agents and optionally conventional additives, wherein the stabilizer mixture used comprisesa) a (meth)allyl polyoxyalkylene ether polymer or its copolymer with vinyl monomers andb) a polyoxyethylene-polysiloxane block copolymer,in a ratio by weight of a:b of 1:9 to 9:1. The polyester foam obtained are open celled to a high degree and have an excellent die-cuttability.

Abstract: Improved ignition resistant, flexible, open-celled polyurethane foams are described. The foams are formed in situ from the reaction, in the presence of a catalyst, of an isocyanate, one or more blowing agents including water, a foam stabilizer, a polyether polyol, melamine, and a standard flame retardant additive. Preferred standard flame retardants are halogenated phosphorus esters and a blend of about 80 to 85% pentabromodiphenyl oxide in an aromatic phosphate plasticizer. The melamine is present in the foam formulations in an amount of from 30 to 40 parts by weight per 100 parts by weight of polyol. The standard flame retardant is present in an amount of from 15 to 25 parts by weight per 100 parts by weight of polyol. The compositions of the invention are particularly suitable for use in furniture, bedding, and carpet padding.

Abstract: In a method for the preparation of highly elastic, cold curing polyurethane foams, equilibrated organofunctional polysiloxanes of the average general formula ##STR1## wherein R.sup.1 is methyl or R.sup.2,R.sup.2 is chloropropyl,n has a value of 0 to 12,m has a value of 1 to 8 when R.sup.1 is methyl and a value of 0 to 6 when R.sup.1 is chloropropyl,are added in amounts of 0.01 to 2.0% by weight, based on the polyols, to the reaction batch.The stabilizing properties of the organofunctional polysiloxanes are superior to those of the known products. The foams, produced pursuant to the invention, have a coarser cell structure and a higher elasticity. The foams are more open-celled as measured by the impression force.

Abstract: Foaming during setting of a polyurethane fixed dressing, e.g. cast for broken arm, is minimized by utilizing as the dressing a polyisocyanate composition comprising:a) at least one organic polyisocyanate,b) at least one catalyst andc) at least one compound of the formula ##STR1## in which R represents methyl, ethyl or propyl and 1.ltoreq.n.ltoreq.4.

Abstract: Stable flame-retardant polyol-oxidated silicon-acidic boron emulsions are produced by mixing and reacting a liquid organic polyol, and oxidated silicon compound and an acidic boron compound. This flame-retardant emulsion is useful in the production of flame-retardant polyurethane, polyester and polyesteramide products.

Abstract: Flexible foam is prepared using 1,1,1-trichloroethane as the sole or predominant auxiliary blowing agent.

Abstract: The subject invention provides a urethane foam which does not require chlorofluorocarbons to manufacture and which conforms to the Montreal Protocol. The compositions of the subject invention are usable in a spray and a pourable form, and may be used in a variety of applications such as in the production of building panels, marine floatation, and roofing materials.

Abstract: A fine-cell rigid polyurethane foam is prepared by reacting a polyol having a blowing agent such as water incorporated therein with a polyisocyanate in the presence of an amine catalyst having a retarding effect. The amine catalyst is comprised of (a) 30 to 50 parts by weight of triethylene diamine, (b) 30 to 50 parts by weight of bis(dimethylaminoethyl)ether and/or N,N',N",N"-pentamethyldiethylene triamine, (c) up to 40 parts by weight of tetramethylhexamethylene diamine and/or trimethylaminoethylpiperazine, and (d) formic acid in an amount of 0.2 to 1.5 moles per mole of triethylene diamine.

Abstract: The present invention relates to a process for strengthening geological formations in underground mining or underground construction work by the introduction of reaction mixtures which react to form polyurethane plastics into the formations which are required to be strengthened, wherein the reaction mixtures are based on(a) a polyisocyanate component,(b) a polyol component and(c) at least one auxiliary agent or additive, characterized in that component (c) contains a cyclic polydimethylsiloxane in the molecular weight range of 222 to 740 and in a quantity of about 0.01 to 5.0% by weight, based on the total weight of components (a) and (b).

Abstract: The present invention relates to the obtention of a rigid polyurethane compound, cellular or micro-cellular, reinforced or not, having a density ranging from 0.20 to 1.30 g/cm.sup.3 ; the formation of this compound happens through the mixing of a resin composed of a mixture of polyether and polyester polyols aminated or not, having a molecular weight ranging from 100 to 5000, employed at 5 to 100 parts by weight; surfactant based on dimethylpolysiloxane, employed at 0.1 to 5 parts by weight; amine catalysts of the tetramethylethylenediamine and dimethylcyclohexylamine type employed at 0.

Abstract: A fine-cell rigid polyurethane foam is prepared by reacting a polyol having a blowing agent such as water incorporated therein with a polyisocyanate in the presence of an amine catalyst having a retarding effect. The amine catalyst is comprised of (a) 30 to 50 parts by weight of triethylene diamine, (b) 30 to 50 parts by weight of bis(dimethylaminoethyl)ether and/or N,N',N",N"-pentamethyldiethylene triamine, (c) up to 40 parts by weight of tetramethylhexamethylene diamine and/or trimethylaminoethylpiperazine, and (d) formic acid in an amount of 0.2 to 1.5 moles per mole of triethylene diamine.

Abstract: Foam compositions with improved physical characteristics are from urethane prepolymers in the presence of various modifying agents. Blowing agents employed in the presence of surfactants make it possible to obtain either open or closed cell structures, and the degree of foam stiffness may be desirably controlled with polyols, as well as with polymeric polymethylene polyphenylisocyanates. Suitable modifying agents include asphalts, portland cement, epichlorohydrin, other epoxidized compounds, additional polymers, and various other materials.

Abstract: Fluid polymer/polyol dispersions are prepared from novel polyether polyols.

Abstract: Novel siloxane-polyether polymers are provided containing cyclic siloxanes which are useful in silicone surfactants for foam polyurethane foam applications. The novel polymers are prepared by reacting a polyhydridosiloxane polymer with a cyclic polysiloxane containing a vinyl group and with an allyl started polyoxyalkylene polymer in the presence of a platinum catalyst. The resulting polymeric products are highly potent and impart flat breathability profiles to foams when used as surfactants in their preparation.

Abstract: The invention pertains to flame retardant flexible polyurethane foams prepared by reacting a polyether polyol, or organic isocyanate, and a blowing agent incorporating (a) melamine in an amount ranging from about 30 weight percent to about 55 weight percent and an effective amount of (b) another flame retardant.

Abstract: The present invention is directed to a process for the production of optionally cellular, polyurethane elastomer moldings or optionally cellular, rigid structural polyurethanes by reacting a reaction mixture containing(i) a polyisocyanate,(ii) a high molecular weight polymer having at least two hydroxy groups and having a molecular weight of 400 to about 10,000,(iii) about 5 to 50% by weight, based on the weight of component (ii) of a chain-extender having at least two hydroxy groups and(iv) about 0.05 to 10 weight percent, based on the weight of components (ii) and (iii) of a salt based on a carboxy functional siloxane and an amidine group-containing compound of the formula ##STR1## wherein R.sub.1, R.sub.2 and R.sub.

Abstract: Described are flexible polyimide foams having enhanced compression fatigue life and softness for use in the manufacture of seat cushions and methods for the production of such foams and precursors therefor. These foams are produced from novel polyimides prepared by reaction of an organic tetracarboxylic acid or derivative thereof, preferably an ester with (a) about 1 to about 50 mol percent of a diester of (i) a primary amino-substituted aromatic carboxylic acid, and (ii) a polymethylene glycol, and (b) at least one aromatic or heterocyclic primary diamine. Foams can be produced having (a) a fatigue life as determined by ASTM test procedure D 3574-81 using foam specimens from three to five inches in thickness of at least 15,000 cycles, or (b) an indentation force deflection as determined by ASTM test procedure D3574-81 on foam specimens of one-inch thickness of less than 40 pounds of force at 25% deflection and less than 180 pounds of force at 65% deflection, or both of (a) and (b).

Abstract: Improved, flexible, open celled polyurethane foams are described. The foams are formed in situ from the reaction of a polyisocyanate, a conventional polyester polyol, a polyether polyol, a high hydroxyl polyester polyol and a blowing agent in the presence of a catalyst. A polyether foam stabilizer is normally also included. A small amount of a destabilizing silicone ingredient can also be included. Useful high hydroxyl number polyester polyols have hydroxyl numbers in the range 300-600, and preferably 400-450. The average equivalent weight of the useful high hydroxyl number polyester polyol is normally in the range 100-200. The compositions of the invention are useful as filter media and are especially suitable for outdoor seating applications.

Abstract: Methods for rapidly curing flexible polyether-derived foam in situ by adding to the foam forming composition an ammonia containing material having a decomposition temperature below the temperature of the highest reaction exotherm of the foam-forming composition and decomposing the ammonia containing material by exposure to the heat of the exotherm produced by reaction of the foam-forming components to release ammonia to cure the foam by contact therewith.

Abstract: Described are flexible polyimide foams having enhanced compression fatigue life and softness for use in the manufacture of seat cushions and methods for the production of such foams and precursors therefor. These foams are produced from novel polyimides prepared by reaction of an organic tetracarboxylic acid or derivative thereof, preferably an ester with (a) about 1 to about 50 mol percent of a diester of (i) a primary amino-substituted aromatic carboxylic acid, and (ii) a polymethylene glycol, and (b) at least one aromatic or heterocyclic primary diamine. Foams can be produced having (a) a fatigue life as determined by ASTM test procedure D 3574-81 using foam specimens from three to five inches in thickness of at least 15,000 cycles, or (b) an indentation force deflection as determined by ASTM test procedure D3574-81 on foam specimens of one-inch thickness of less than 40 pounds of force at 25% deflection and less than 180 pounds of force at 65% deflection, or both of (a) and (b).

Abstract: Described are flexible polyimide foams having enhanced compression fatique life and softness for use in the manufacture of seat cushions and methods for the production of such foams and precursors therefor. These foams are produced from novel polyimides prepared by reaction of an organic tetracarboxylic acid or derivative thereof, preferably an ester with (a) about 1 to about 50 mol percent of a diester of (i) a primary amino-substituted aromatic carboxylic acid, and (ii) a polymethylene glycol, and (b) at least one aromatic or heterocyclic primary diamine. Foams can be produced having (a) a fatigue life as determined by ASTM test procedure D3574-81 using foam specimens from three to five inches in thickness of at least 15,000 cycles, or (b) an indentation force deflection as determined by ASTM test procedure D3574-81 on foam specimens of one-inch thickness of less than 40 pounds of force at 25% deflection and less than 180 pounds of force at 65% deflection, or both of (a) and (b).

Abstract: A method of manufacturing asphalt foam comprising the steps of preparing polyether polyol containing 15 mole % or more of ethylene oxide, preparing urethane prepolymer by making the polyether polyol react with organic isocyanate, and obtaining asphalt foam by mixing the urethane prepolymer with (i) a silicone oil and (ii) an aqueous emulsion of asphalt to obtain an asphalt foam having a five cell structure and excellent water repellancy.

Abstract: The present invention is directed to a process for the production of optionally cellular, polyurethane elastomer moldings or optionally cellular, rigid structural polyurethanes by reacting a reaction mixture containing(i) a polyisocyanate,(ii) a high molecular weight polymer having at least two hydroxy groups and having a molecular weight of 400 to about 10,000,(iii) about 5 to 50% by weight, based on the weight of component (ii) of a chain-extender having at least two hydroxy groups and(iv) about 0.05 to 10 weight percent, based on the weight of components (ii) and (iii) of a salt based on a carboxy functional siloxane and an amidine group-containing compound of the formula ##STR1## wherein R.sub.1, R.sub.2 and R.sub.

Abstract: A polyurethane foam composition for immobilization in traumatology containing the following components in mass %:hydroxyl-containing polyester: 20-30catalyst: 0.5-3.0foaming agent: 0.5-7.0foam stabilizer: 0.5-0.9low molecular polyolefin: 20-30polyisocyanate ensuring the ratio of the isocyanate and hydroxyl groups in the polyester equal to 1:1: the balance.

Abstract: Amine compounds are added to foamable elastomeric silicone foam to reduce foam density.

Abstract: Urethane and oxazolidone-containing isocyanurate foams characterized by cracking resistance and scorching resistance and thermal stability at a temperature of about 160.degree. C. or higher. These foams are produced by reacting at least one polyisocyanate with at least one polyepoxide and at least one polyol in the presence of catalyst, surfactant, and blowing agent.

Abstract: The present invention is directed to a process for the production of optionally cellular, polyurethane elastomer moldings or optionally cellular, rigid structural polyurethanes by reacting a reaction mixture containing(i) a polyisocyanate,(ii) a high molecular weight polymer having at least two isocyanate-reactive groups and having a molecular weight of 400 to about 10,000,(iii) about 5 to 50% by weight, based on the weight of component (ii) of a chain-extender having at least two isocyanate-reactive groups and(iv) about 0.05 to 10 weight percent, based on the weight of components (ii) and (iii) of a salt based on a carboxy functional siloxane and an amidine group-containing compound of the formula ##STR1## wherein R.sub.1, R.sub.2 and R.sub.

Abstract: Treated filler having surface nitrogen groups is added to silicone foam to reduce density.

Abstract: Silicone flexible foams of good fire-resistance and extremely low density from about 5 to 14 lbs/ft..sup.3, having good mechanical and physical properties, are provided. The curable and foamable compositions are prepared from a multi-component mixture comprising, as part A, a high molecular weight uncured vinyl-terminated siloxane polymer, a polydimethyl silanol terminated reactive diluent, and an inorganic filler to improve fire resistance, water and a complex platinum catalyst, and as part B, a polydimethyl hydrogen siloxane. The viscosity of part A of the mixture prior to gelling and foaming is from about 30,000-65,000 cps. This mixture becomes foamable and curable at ambient temperature.

Abstract: A storage-stable premix composition for use in a foam-forming reaction with an organic polyisocyanate in the manufacture of a polyurethane or polyisocyanurate foam comprising(a) at least one polyol,(b) at least one halogenated organic blowing agent,(c) at least one amine catalyst, and(d) a stabilizing amount of at least one polyvalent metal-containing organometallic compound.Some organometallic compounds of the invention have a slight catalytic effect but do not have the pronounced activity of conventional urethane and isocyanurate catalysts such as dibutyltin dilaurate and stannous octoate.

Abstract: The present invention is directed to a process for the production of waterproof, fine-cell polyurethane elastomers having a density of about 300 to 800 kg/m.sup.3 by reacting(a) organic polyisocyanates,(b) polyhydroxyl compounds having a molecular weight of about 400 to about 8000,(c) water and, optionally,(d) organic chain-extending agents containing at least two isocyanate-reactive hydrogen atoms and having a molecular weight of 32 to 399,the equivalent ratio of isocyanate groups to NCO-reactive groups in the overall formulation being about 0.90:1 to 1.20:1, characterized in that polysiloxane ionomers are added to the water/crosslinker component in concentrations of about 0.1 to 5% by weight, based on the reaction mixture as a whole.

Abstract: A method of making a reaction injection molded polyurethane having enhanced mold release properties is provided. An effective amount at least one dithiocarbamate is injected into a mold cavity with at least one a polyisocyanate component and at least one an active hydrogen component.Polyurethanes having enhanced mold release properties are formed using a composition of matter comprising at least 0.25 parts per hundred parts by weight of active hydrogen components of a dithiocarbamate of the formula: ##STR1## wherein M and the R groups are described herein.

Abstract: Rigid polyurethane foams produced by reacting a polyol component having a special composition with an isocyanate component in the presence of a blowing agent, a reaction catalyst and a foam stabilizer with a mold release time of as short as 5.5 minutes or less, have remarkably low thermal conductivity of 12.5.times.10.sup.-3 Kcal/m.hr..degree.C. or less and a low density and are suitable as heat insulating materials for refrigerators and the like.

Abstract: This invention is an active hydrogen-containing composition suitable for the production of flexible polyurethane foam when reacted with a polyisocyanate, said composition comprising,(a) a polyol having an average functionality of about 2.0 to about 4.0, having at least about 50% of its active hydroxyl groups in the form of primary hydroxyl groups, and an equivalent weight from about 500 to about 5000;(b) from about 0.5 to about 5 parts, per 100 parts by weight of component (a) of a crosslinker selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, methylene bis(o-chloroaniline) and mixtures thereof; and(c) at least about 0.

Abstract: In one aspect, this invention is a polyurethane foam which is the reaction product of a reaction mixture comprising a poly(alkylene carbonate) polyol, a silicone surfactant, a blowing agent, and a polyisocyanate.In another aspect, this invention is an active hydrogen-containing composition comprising a poly(alkylene carbonate) polyol having an equivalent weight from about 100 to about 3000, a blowing agent and a silicone surfactant.

Abstract: Novel blowing agents for foamable organopolysiloxane compositions, notably the platinum-catalyzed such organopolysiloxane compositions, comprise admixture of calcium carbonate and an organic carboxylic acid.

Abstract: This invention is concerned with a method for producing phenol resin foam possessing a compact cellular structure, a high closed cell ratio and improved heat resistance. The method consists of using a resole type phenolic resin having a number average molecular weight of 150-400, surface active agents, blowing agents and curing agents, wherein at least two surface active agents are chosen from general formulas A and B, but a selection of each type must be employed ##STR1## where R.sub.1 is a saturated aliphatic hydrocarbon group of 8-14 carbon atoms and/or a 2-phenylpropyl group, and m and n are integers and meet the requirement: ##EQU1## R.sub.2 is a saturated aliphatic hydrocarbon group of 4-12 carbon atoms, M is a hydrogen atom or SO.sub.2 Na, and x is an integer of 4-110.

Abstract: Process for the preparation of flexible polyurethane foams using polysiloxane-polyoxyalkylene block copolymers as stabilizers having the general formula: ##STR1## in which A represents A.sup.1 and A.sup.2 polyoxyalkylene blocks, as defined hereinafter, which are linked to silicon over carbon and which have the general formula --R.sup.2 --O--(C.sub.x H.sub.2x O--).sub.y R.sup.3, R.sup.2 being a divalent hydrocarbon radical with 2 to 4 carbon atoms and R.sup.3, x and y are as defined hereinafter,B is a methyl radical, the A or R.sup.1 radical,R.sup.1 is an alkyl radical with 1 to 12 carbon atoms, a substituted alkyl radical with 1 to 12 carbon atoms, an aryl or an alkaryl radical,n has a value of 30 to 200,m has a value of 3 to 20 when B is a methyl radical or corresponds to the R.sup.1 radical, and a value of 1 to 18 when B corresponds to the A radical,o has a value of 0 to 40, n being not less than 5 m, and m and o being not greater than 1/3 n,with the proviso that(a) the A.sup.

Abstract: A new class of hydrocarbon foaming agents which are block copolymers, one block of which is a styrene derivative, the other a vinylsilane derivative. Said hydrocarbon foaming agents are nonreactive with common anionic initiators.

Abstract: Improved crack-free rigid cellular polyisocyanurate polymers are disclosed that are derived from the reaction of an organic polyisocyanate combination comprising two particular types of polymethylene polyphenyl polyisocyanates (a) and (b), a trimerization catalyst, minor amount of a polyol, a surfactant, and an inert volatile blowing agent having a boiling point from about 30.degree. C. to about 90.degree. C.The novel rigid foams are particularly useful in preparing high molded bodies of foam by making multiple pours or lifts on top of each other in a mold. The resultant molded body comprises a multiple of molded parts firmly fused to each other and crack-free. Such high molded bodies and process therefor are particularly useful in the insulation of ships.

Abstract: Rigid polyurethane foams produced by reacting a polyol component having a special composition with an isocyanate component in the presence of a blowing agent, a reaction catalyst and a foam stabilizer with a mold release time of as short as 5.5 minutes or less, have remarkably low thermal conductivity of 12.5.times.10.sup.-3 Kcal/m.hr..degree.C. or less and a low density and are suitable as heat insulating materials for refrigerators and the like.