MXPA00005496A - Low density co2-blown polyurethane foams and a process of preparing same - Google Patents

Abstract

Disclosed is a method of preparing a low density CO2-blown foam that has a high closed cell content. Foams prepared by the method of the present invention are useful in pour-in-place applications such as garage doors, doors, walk-in coolers, portable coolers, refrigerators, and water heaters, for example. Use of the method described herein reduces foam leakage from a mold during pour-in-place operations, and thus reduces waste and the cost associated with producing foam-filled articles made using a pour-in-place procedure.

Description

POLYURETHANE FOAMS BLOWED WITH LOW DENSITY CQ2 AND A PROCESS TO PREPARE THEM This invention relates to polyurethane foams blown with CO2. This invention particularly relates to polyurethane foams blown with low density C02 and to a method for manufacturing them. - Polyurethane and polyisocyanurate foams (hereinafter, foams), can be used in a variety of applications. As used herein, the term "foams" will be understood to include polyisocyanurate foams modified with polyurethane, and polyisocyanurate foams. • Rigid polyurethane foams, for example, can provide support in applications where a rigid support is desirable. These applications include: - materials for construction of roofs, eaves, building panels, insulation of pipes, and insulation of containers; floatation; floral and craft foams; and lightweight structural parts for the marine, aerospace, and other industries, for example. Rigid foams can be prepared by different methods, including the processes of block foam, double-band lamination, discontinuous panel, and pouring in place. The processes of lamination of double band discontinuous panel, and poured in the place, can each be used to prepare a rigid foam in the site in a single step. An on-site pouring process (PIP) is a process where a polyurethane foam formulation is poured into a cavity, mold, or empty housing (subsequently in the present, mold), and the foam fills the mold to form a foam filled article. The on-site pouring process and its useful applications are well known in the art of preparing polyurethane foams (see, for example, Reaction Polymers; Gum, .F., Riese,., And Ulrich, H. Eds. Hanser: New York 1992, page 575). Items made by the landfill method include, for example, garage doors, chillers to enter, portable chillers, refrigerators, doors, and water heaters. The foams described herein include rigid foams, molded foams, and foams in slab supply. When used in an on-site pouring process, a polyurethane foam formulation can escape or leak from a mold if foaming does not occur during, or soon after, pouring. Leakage from a mold can result in higher costs associated with the production of a foam product, due to product loss and higher maintenance costs. In current practice, leakage is typically reduced by the addition of a low-boiling compound at room temperature, to a foaming system, to improve the previous expansion of the foaming system, or foam formation, of the Foaming system, at the beginning of the polyurethane reaction. However, this practice usually requires a modification of conventional equipment. The prior expansion, as used herein, refers to an increase in the volume of a foaming system, ie, a polyurethane-forming reaction mixture, before the reaction of the polyurethane is initiated. Polyurethane foams typically use blowing agents, such as halogenated alkanes, to produce the cellular structure found in a polyurethane foam. The C02 can be a useful blowing agent. CO 2 can be produced as a result of a reaction between an isocyanate and water, when water is included in a polyurethane foam formulation. The use of water and C02 can help reduce the amount of halogenated alkanes used in the manufacture of a polyurethane foam.

This can result in the reduction of the amount of halogenated alkanes released into the atmosphere, which may be desirable. Polyurethane foams can be made using water or C02 or a combination thereof, exclusively as the blowing agent. These foams (hereinafter, foams blown with C02) are described in U.S. Patent Number 5,013,766, for example. C02 blown foams typically can be high density foams, ie, foams having an overall density greater than about 0.0368 grams per cubic centimeter (gcc). C02 blown foams having a low density can be obtained by conventional methods, but these foams can have a low content of closed cells. In certain applications where a low density polyurethane foam having a high content of closed cells is desirable, typical C02 blown foams may be undesirable. In the technique of preparing rigid polyurethane foams, it would be desirable to prepare a low density C02 blown foam having a high content of closed cells. It would also be desirable in the art of the preparation of rigid foams to reduce leakage in a pouring process in place. In one aspect, the present invention is a polyurethane foam formulation comprising a polyisocyanate composition, and a polyol composition, wherein the polyol composition includes: (a) at least one polyol initiated by aromatic amine; (b) at least one alkylene carbonate; and (c) water.2 In another aspect, the present invention is a low density C02 blown foam prepared from a polyurethane foam formulation comprising a polyisocyanate composition and a polyol composition, wherein the composition of polyol includes: (a) at least one polyol initiated by aromatic amine; (b) at least one alkylene carbonate; and (c) water. In still another aspect, the present invention is a process for the preparation of a polyurethane filled article, which comprises the steps of: (i) pouring a polyurethane foam formulation into a mold; (ii) allow the foam to fill the mold; and (iii) demolding the foam after the foam becomes cured to obtain the polyurethane filled article, 2 wherein the polyurethane foam formulation comprises a polyisocyanate composition and a polyol composition, and wherein the polyol composition includes: (a) at least one polyol initiated by aromatic amine; (b) at least one alkylene carbonate; and (c) water. Using the process of the present invention, the problem of mold leakage can be reduced when a pouring method is used in place to prepare a foam. A foam blown with C02 obtained using the process of the present invention, is a low density foam that can have a reduction of 15 percent to 30 percent in overall density relative to the foams produced by conventional practice. In one embodiment, the present invention is a foam formulation useful for the preparation of a foam blown with C02. A foam formulation of the present invention includes a polyisocyanate composition and a polyol composition. When the polyisocyanate and polyol compositions are combined under suitable reaction conditions, a low density polyurethane foam of the present invention is obtained. A polyol composition of the present invention includes a material that reacts with isocyanate, an alkylene carbonate, and water. In addition, optional components may be included in either or both components of the foam formulation. Isocyanate-reactive materials suitable for use in the practice of the present invention include aromatic amine-initiated polyols (AAP). Suitable AAPs for use in the practice of the present invention can be obtained commercially. For example, Voranol 391 (Commercial Designation of Dow Chemical Co.) is a commercially available polyol suitable for the practice of the present invention. Voranol 391 is a polyol initiated by aromatic amine prepared from o-toluenediamine, ethylene oxide, and propylene oxide. In general, the aromatic amine initiated polyols can be obtained by the reaction of an aromatic amine with an alkylene oxide under suitable reaction conditions of, for example, temperature, pH, and catalyst. For example, a suitable temperature scale for preparing a polyol initiated by aromatic amine of the present invention, may be from 100 ° C to 135 ° C. Preferably, the temperature is in the range of 110 ° C to 130 ° C. More preferably, the temperature is in the range of 120 ° C to 130 ° C, and most preferably 125 ° C to 130 ° C. A polyol initiated by aromatic amine of the present invention can be obtained at a pH in the range of 7.5 to 12. Preferably, the pH is from 8 to 11.5. More preferably the pH is from 8.5 to 11, and most preferably from 9 to 11. A catalyst can be included to obtain a polyol initiated by aromatic amine of the present invention. Suitable catalysts for the preparation of polyols of the present invention include, for example, dimethylcyclohexyl amine, dimethylethanolic amine, and diethylenetanolic amine, similar compounds, and mixtures thereof, - metal hydroxides of Group I and Group II, such as hydroxide of sodium, calcium hydroxide, barium hydroxide, lithium hydroxide, similar compounds, and mixtures thereof.

A polyol initiated by aromatic amine suitable for the practice of the present invention, can have a molecular weight of 425 to 900. Preferably, the molecular weight of a polyol initiated by aromatic amine is from 520 to 825. More preferably, the molecular weight of a polyol initiated by aromatic amine is from 560 to 640. Most preferably, the molecular weight of a polyol initiated by aromatic amine is from 560 to 590. The hydroxyl number of a polyol initiated by aromatic amine of the present invention, can be from 250 to 530. Preferably, the hydroxyl number is in the range of 325 to 465. More preferably the hydroxyl number is in the range of 350 to 450, and most preferably from 380 to 430. The average functionality of a polyol initiated by aromatic amine of the present invention is preferably not less than 2. More preferably, the average functionality of a polyol initiated by aromatic amine is from 3 to 5. Most preferably, the average is from 3.2 to 4.1. The polyols of the present invention are prepared from alkylene oxides and an aromatic amine initiator. Aromatic amines suitable for the preparation of an aromatic amine initiated polyol of the present invention may include any di- or polyfunctional aromatic amine. Suitable aromatic amines include: the isomers of toluenediamine (TDA), which include 2,6-TDA, and 2,4-TDA, for example, isomers of methylenediamine (MDA) including, for example, 2 '- MDA, 2.4 '-MDA, and 4.4' -MDA; MDA oligomers including, for example, mixtures of isomeric compounds having from 3 to 6 aromatic rings; alkyl derivatives of aromatic amines such as 4-methyl-2,6-TDA and isomers of dimethyl-MDA; halogenated derivatives of TDA such as 3-chloro-2,4-TDA; similar compounds and mixtures of any of them. Alkylene oxides suitable for use in the present invention include oxides having from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms. For example, suitable alkylene oxides may be oxides of ethylene, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide, epichlorohydrin, 3-methyl-2-oxide, 2- butylene, similar compounds and mixtures thereof. In the present invention, polymers and copolymers of propylene oxide are preferred. In a foam formulation of the present invention, a polyol initiated by aromatic amine may be present as the sole polyol component in a polyol composition, or optionally, other polyols may be included in the composition. If included, other polyols may be present in an amount of 1 to 50 weight percent of the total polyol. Preferably, 0 to 10 weight percent of another polyol is included. The water is water included in a polyol composition of the present invention, in an amount of 1 to 12 parts per 100 parts of polyol initiated by aromatic amine, by weight.

Give preference, water is included in an amount of 3 to 9 parts. More preferably, water is included in an amount of 5 to 8, and most preferably water is included in an amount of 6.5 to 7.5 parts per 100 parts of polyol initiated by aromatic amine, by weight. In a foam formulation of the present invention, an alkylene carbonate is included. An alkylene carbonate useful in the practice of the present invention is described by any of structures I or II: II wherein R 1, R 2, R R are each independently hydrogen or a combination thereof with alkyl substituents of I, and wherein R 5 and R g are each independently substituents of alkyl of II. The alkyl substituents of I or II can be alkyl groups having from 1 to 8 carbon atoms. Suitable alkyl substituents can be aliphatic, aromatic, cyclic or acyclic, substituted or unsubstituted. Examples of suitable alkyl substituents include: methyl, ethyl, normal propyl, isopropyl, normal butyl, isobutyl, pentyl, hexyl, cyclohexyl, phenyl, hydroxyphenyl, phenylmethyl, m-ethylphenyl, bromophenyl, chloromethyl, similar compounds, and mixtures thereof. same. For example, suitable alkylene carbonates may include: ethylene carbonate; propylene carbonate; butylene carbonate; styrene carbonate (or l-phenylethylene carbonate); isobutylene carbonate; dimethyl carbonate; diethyl carbonate; tertiary dibutyl carbonate; dibenzyl carbonate; diphenyl carbonate; phenylethyl carbonate; similar compounds, and mixtures thereof. Alkylene carbonates suitable for use in the practice of the present invention are known and commercially available. The purity of an alkylene carbonate is not believed to be critical to the practice of the present invention. For example, propylene carbonate is commercially available as Arconate 1000 from Arco Chemical Co., in a minimum purity of 99 percent, but it is believed that a lower purity does not interfere with the practice of the present invention. An alkylene carbonate of the present invention can be included in an amount of 1 to 20 parts per 100 parts of the polyol initiated by aromatic amine, by weight. Preferably, the alkylene oxide is included in an amount of 3 to 15 parts of alkylene carbonate per 100 parts of polyol initiated by aromatic amine, by weight. More preferably, an alkylene carbonate is included in an amount of 5 to 12 parts of alkylene carbonate per 100 parts of polyol initiated by aromatic amine, by weight. Most preferably, an alkylene carbonate is included in an amount of 7 to 10 parts of alkylene carbonate per 100 parts of polyol initiated by aromatic amine, by weight. In the practice of the present invention, an alkylene carbonate can be included with either the polyol composition or the isocyanate composition. Optionally, the alkylene carbonate can be included as part of both the polyol composition and the isocyanate composition. Preferably, the alkylene carbonate is included in the polyol composition. Optional components may be included in a polyol composition of the present invention. For example, a "polyol composition may optionally include copolymer polyols, polyester polyols, catalysts, fillers, crosslinkers, surfactants, cell openers, mold release agents, and fire retardants, for example. of polyurethane suitable for the preparation of a polyurethane foam of the present invention are tertiary amine catalysts, such as: triethylene diamine, N-methyl morpholine, dimethylethanolic amine, pentamethyldimethylene triamine, N-ethyl morpholine, diethylethanolic amine; co-morpholine, piperazine 1-methyl-4-dimethylaminoethyl, bis (N, N-dimethylaminoethylene), similar compounds, and mixtures thereof Catalysts suitable for use with the present invention may also include those which catalyze the formation of isocyanurates, such as those mentioned in Saunders and Frisch, Poiyurethanes, Chemistry and Technolocry in High Pol? Mers volume XVI, pages 94-97 (1962). These catalysts are referred to as trimerization catalysts. Examples of these catalysts include aliphatic and aromatic tertiary amine compounds, organometallic compounds, alkali metal salts of carboxylic acids, phenols, and symmetrical triazine derivatives. Preferred catalysts are potassium salts of carboxylic acids such as potassium octoate, and the potassium salt of 2-ethylhexanoic acid, and tertiary amines such as, for example, 2,4,6-tris (dimethylaminomethyl) phenol. Amine catalysts are typically used in an amount of 0.1 to 5, preferably 0.2 to 3 parts per 100 parts of the polyol composition, by weight. Organometallic catalysts are also suitable, and examples include organic lead, organic iron, organic mercury, organic bismuth, and preferably organic tin compounds. More preferred are organic tin compounds, such as tin tin dilaurate, dimethyl tin dilaurate, stannous octoate, stannous chloride, and the like. The organometallic compounds are usually used in an amount of 0.05 to 0.2 parts per 100 parts by weight of the polyol composition. Examples of the surfactants that may optionally be included are silicone surfactants, most of which are block copolymers containing at least one polyoxyalkylene segment and a poly (dimethylsiloxane) segment. Other surfactants include polyethylene glycol ethers of long chain alcohols, tertiary amine or alkanolamine salts of long chain alkyl sulfate esters, alkyl sulfonic esters, and alkylarylsulfonic acids. When used, 0.1 to 3, preferably from 0.3 to about 1 part by weight of the surfactant is suitable for 100 parts of polyol by weight. Surfactants prepared from ethylene oxide and butylene oxide, as described in United States Patent Application Serial Number 08 / 342,299 (allowed July 23, 1996), are also useful in practice of the present invention. Examples of the crosslinking agents are dietanolic amine and bis (o-chloroaniline) methylene, and similar compounds. It is known in the art to use cell openers, mold release agents, fire retardants, fillers, and other additives, to modify the properties and assist in the processability of the foam, and may be desirable depending on the application of the foam. end use. A polyisocyanate composition includes a polyisocyanate. Any polyisocyanate or polyisocyanate mixture known in the art is suitable for the practice of the present invention. Useful polyisocyanates are described in U.S. Patent No. 4,785,027, for example. The polyisocyanate can be aliphatic or aromatic. Aromatic polyisocyanates suitable for use herein include: phenyl diisocyanate; 2,4-toluene diisocyanate; 2,6,6-toluene diisocyanate; ditoluene diisocyanate; Naphthalene 1,4-diisocyanate; 2,4'- diisocyanate or a combination thereof with 4,4'-diphenylmethane (MDI); polymethylene polyphenylene polyisocyanates (polymeric MDI); similar compounds, and mixtures thereof. Suitable aliphatic polyisocyanates include: 1,6-hexamene diisocyanate; isofurone diisocyanate; 1,4-cyclohexyl diisocyanate; similar compounds and mixtures thereof. Prepolymers prepared by the reaction of a polyol or a chain extender with a polyisocyanate are also suitable. The polyisocyanate can be used in a suitable amount to prepare a polyurethane-forming composition with an isocyanate index of from 90 to 500. Preferably the index is from 100 to 130. More preferably, the isocyanate index is from 105 to 115. Very preferably, the isocyanate index is from 105 to 110. The isocyanate index is determined by dividing the number of isocyanate equivalents by the number of equivalents of material that reacts with isocyanate, and multiplying the ratio obtained by 100. A polyisocyanate of the present invention it can have an average functionality of 2.0 to 3.5. Preferably, the average functionality is from 2.5 to 3.3. More preferably the average functionality is from 2.6 to 3.2. Most preferably, the average functionality is from 2.6 to 3.0. In another embodiment, the present invention is a method for the preparation of a polyurethane filled article, by the method of pouring in place, using a foam formulation described herein. In general, in an on-site pouring operation, the foaming typically is delayed until the start of the reaction inside the cavity of a mold. In the process of the present invention, a prior expansion occurs when the foam formulation is initially poured into a mold, due to the presence of the alkylene carbonate. The alkylene carbonate present in a foam formulation of the present invention generates C02 during storage at controlled temperatures. Initial foaming prevents the foaming of an unsealed mold, and subsequent foaming improves the mold filling process. In the present invention, a polyurethane filled article is obtained according to the steps of: mixing a polyisocyanate composition and a polyol composition at a suitable isocyanate index as described herein; pouring the polyurethane forming mixture into a mold; allowing the foam mixture to fill the mold to obtain a rigid molded foam; and demolding the foam after the foam becomes cured to obtain the polyurethane filled article. In a process of the present invention, a polyol composition including an alkylene carbonate, can be stored at a temperature of 10 ° C to 60 ° C. Preferably, a composition containing alkylene carbonate is stored at a temperature of 16 ° C to 32 ° C, more preferably at a temperature of 18 ° C to 27 ° C, and most preferably at a temperature of 21 ° C to 24 ° C. ° C. In yet another embodiment, the present invention is a low density C02 blown foam prepared from a foam formulation described herein. A foam of the present invention has properties that are at least equivalent to foams made in accordance with conventional processes. One property of a foam that can be improved by using the process of the present invention is the overall density of a foam, while maintaining the dimensional stability of the foam. The overall density is the density of the entire molded rigid foam part. A foam made in accordance with the process of the present invention may have an overall density not greater than 0.16 grams per cubic centimeter. Preferably, a foam of the present invention can have a density of not more than 0.08 grams per cubic centimeter, more preferably 0.048 grams per cubic centimeter. Most preferably, a foam of the present invention has a density not greater than about 0.0352 grams per cubic centimeter. Another property of a foam that can be improved by using the process of the present invention is the closed cell content of a foam. A foam obtained using the process of the present invention can have a closed cell content of not less than 80 percent. Preferably, a foam of the present invention has a closed cell content of not less than 85 percent. More preferably, the content of closed cells is not less than 90 percent, and most preferably is not less than 92 percent. It is of particular importance in the present invention, that a foam prepared in accordance with the process of the present invention, may have a low density, adequate dimensional stability, and a high content of closed cells. The suitable dimensional stability for a foam of the present invention is a volume change from 0 to +, 8 percent, for example. Preferably, the dimensional stability is a volume change from 0 to ± 6 percent, and most preferably a volume change from 0 to ± 4 percent. A foam of the present invention additionally provides excellent adhesion to different substrates, for example plastic coating materials, such as high impact polystyrene and high density polyethylene, as well as steel faces. At the same time, a foam of the present invention maintains excellent dimensional stability at a density of not less than 0.0288 grams per cubic centimeter under conditions of cold aging, dry aging and wet aging. A foam of the present invention exhibits a finer and more uniform cell structure than a conventionally prepared foam. Other attributes of the foam that can be attributed to the process of the present invention are: low free-rise density of less than about 0.0176 grams per cubic centimeter, preferably from 0.0152 to 0.0176, more preferably from 0.0152 to 10.01712, and most preferably from 0.0152 to 0.0168 grams per cubic centimeter; a low fragility of the core foam not greater than about 3.0 percent, preferably from 1.0 percent to 3.0 percent, more preferably from 1.0 percent to 2.5 percent, and most preferably from 1.0 percent to 2.0 percent; and a fast unmolding. A foam prepared according to the process of the present invention can generally be demolded in less than about 8 minutes. Preferably, a foam of the present invention is demoulded in 3 minutes to 8 minutes, more preferably in 3 minutes to 7 minutes. Most preferably, a foam of the present invention is demoulded in 3 minutes to 6.5 minutes. The demolding time depends on the thickness of the foam obtained, and the ranges described herein are given for a foam thickness of approximately 4,445 centimeters.

EXAMPLES The following examples and comparative examples are intended to be illustrative of the present invention. These examples and comparative examples are not intended to limit the scope of the claims of the present invention, and should not be construed in that manner.

Example 1 A polyol composition was prepared by mixing polyol, propylene carbonate, and water, with the optional components, in the amounts mentioned in Table 1.

Example 2 A polyol composition was prepared by mixing polyol, propylene carbonate, and water, with the optional components, in the amounts mentioned in Table 1.

Example 3 - Comparative Example A polyol composition was prepared by mixing polyol and water with the optional components, in the amounts mentioned in Table 1.

Example 4 - Comparative Example A polyol composition was prepared by mixing polyol and water with the optional components, in the amounts mentioned in Table 1.

Example 5 - Comparative Example A polyol composition was prepared by mixing polyol and water with the optional components, in the amounts mentioned in Table 1.

Example 6 - Comparative Example A polyol composition was prepared by mixing polyol and water with the optional components, in the amounts mentioned in Table 1.

Example 7 The polyol composition of Example 1 was combined with 215 parts of isocyanate PAPI R 27, up to an isocyanate index of 105. The polyurethane-forming mixture thus produced was poured into a heated mold at a temperature of 54.4 ° C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The foam reactivity profile is shown in Table 3. The physical properties of the foam were determined according to the following procedures: a. The density of the foam was determined at the (global) location by the formula D = W / V, where D was the density of a foam, was the weight of the foam, and V was the volume of the foam. b. The density of the core was determined according to ASTM D-1622. c. The factor k was determined according to ASTM C-518. d. The compressive strength was determined according to ASTM D-1621. d. Fragility was determined according to ASTM e. Dimensional stability was determined according to ASTM D-2126. f. The content of closed cells was determined according to ASTM D-2856.

Example 8 - Comparative Example The polyol composition of Example 3 was combined with 173 parts of isocyanate PAPIR 27, up to an isocyanate index of 110. The polyurethane-forming mixture thus produced was poured into a heated mold at a temperature of 54.4 °. C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

Example 9 - Comparative Example The polyol composition of Example 4 was combined with 214 parts of isocyanate PAPI R 27, up to an isocyanate index of 110. The polyurethane-forming mixture thus produced was poured into a mold heated to a temperature of 54.4 ° C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

Example 10 - Comparative Example The polyol composition of Example 5 was combined with 173 parts of isocyanate PAPIR 27, up to an isocyanate index of 110. The polyurethane-forming mixture thus produced was poured into a heated mold at a temperature of 54.4 °. C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

EXAMPLE 11 Comparative Example The polyol composition of Example 6 was combined with 214 parts of isocyanate PAPIR 27, up to an isocyanate index of 110. The polyurethane-forming mixture thus produced was poured into a mold heated to a temperature of 54.4 ° C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

Example 12 The polyol composition of Example 1 was combined at 28.8 ° C with 215 parts of isocyanate PAPIR 27, up to an isocyanate index of 105. The polyurethane-forming mixture thus produced was poured into a heated mold at a temperature of 54.4. ° C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

Example 13 The polyol composition of Example 3 was combined to 173 parts of isocyanate PAPI 27, up to an isocyanate index of 110. The polyurethane-forming mixture thus produced was poured into a heated mold at a temperature of 54.4 ° C. The foam was removed from the mold after 4.5 minutes. Some physical properties of the foam are tabulated in Table 2. The profile of foam reactivity is shown in Table 3.

Table 1 * It is not an example of the present invention + Vorasurf® 504 (R Commercial Designation of Dow Chemical Co.). a Dimethylcyclohexyl amine. ToyocatTM F94 (Commercial Designation of Tosoh Corp.) cCuritha-? ER 52 (Commercial Designation of Dow Chemical Co.). ^ Available at Akzo Chemical Co.

Table 2 95 percent relative humidity No data. The properties could not be measured due to the collapse of the foam.

Table 3 It is not an example of the present invention. Manual pouring @ 22.2 ° C. There is no data. The properties could not be measured due to the collapse of the foam.

Claims (20)

1. CLAIMS 1. A polyurethane foam formulation comprising: (1) a polyisocyanate composition, and (2) a polyol composition, wherein the polyol composition includes: (a) at least one polyol initiated by aromatic amine; (b) at least one alkylene carbonate; and (c) water. The polyurethane foam formulation of claim 1, wherein the aromatic amine initiated polyol is prepared using an aromatic amine selected from the group consisting of: TDA isomers; MDA isomers; and MDA oligomers. 3. The polyurethane foam formulation of claim 2, wherein the aromatic amine is selected from the group consisting of: TDA isomers; and MDA isomers. 4. The polyurethane foam formulation of claim 3, wherein the aromatic amine is selected from TDA isomers. 5. The polyurethane foam formulation of claim 4, wherein the aromatic amine is o-TDA. 6. The polyurethane foam formulation of claim 1, wherein the alkylene carbonate is selected from the group consisting of: ethylene carbonate; propylene carbonate; butylene carbonate; dimethyl carbonate; diphenyl carbonate, - ^ and diethyl carbonate. 7. The polyurethane formulation of claim 6, wherein the alkylene carbonate is propylene carbonate. 8. A polyurethane foam blown with CC > 2 of low density, prepared from the polyurethane foam formulation of claim 1. 9. The low density CO2 blown polyurethane foam of claim 8, wherein the overall density of the foam is not greater than 0.08 grams per cubic centimeter. 10. The low density C02 blown polyurethane foam of claim 9, wherein the overall density of the foam is not greater than 0.048 grams per cubic centimeter. 11. The low density C02 blown polyurethane foam of claim 10, wherein the overall density of the foam is not greater than 0.0352 grams per cubic centimeter. 12. The low density C02 blown polyurethane foam of claim 8, wherein the foam has a closed cell content of not less than 85 percent. 13. The low density C02 blown polyurethane foam of claim 12, wherein the foam has a closed cell content not greater than 90 percent. 14. The low density C02 blown polyurethane foam of claim 13, wherein the foam has a closed cell content of not less than 92 percent. 15. A process for the preparation of a polyurethane filled article, which comprises the steps of: (i) pouring a polyurethane foam formulation into a mold; (ii) allowing the foam to fill the mold, - and (iii) demolding the foam after the foam becomes cured to obtain the polyurethane filled article. 16. The process of claim 15, wherein the foam is prepared by a pouring method in place, and where leakage of a mold is reduced in relation to a pouring procedure in the place where a mold is not used. The formulation of claim 1. 17. The process of claim 15, wherein the polyol composition is stored at a temperature of 10 ° C to 60 ° C before being combined with the polyisocyanate composition. 18. A polyurethane filled article prepared by the process of claim 15. 19. The polyurethane filled article of claim 18, wherein the article is a door, - a refrigerator; a portable cooler; a cooler to enter; a garage door; or a water heater. 20. The polyurethane filled article of claim 18, wherein the article is a door.