Imide-containing polyol, method for producing imide-containing polyol, and method for using imide-containing polyol

Abstract

SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure are directed to imide-containing polyols, methods for making imide-containing polyols, and methods for using imide-containing polyols.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to imide-containing polyols and methods of making and using them. [Background technology]

[0002] Rigid polyurethane and polyisocyanurate foams are used as thermal insulation materials in buildings, vehicles, and appliances, among other applications. Foams of this type are produced by reacting a foam formulation containing one or more isocyanates, one or more polyols, and one or more blowing agents. Summary of the Invention

[0003] The present disclosure provides various embodiments, including the following: a) a method for producing an imide-modified polyol composition, the method comprising: a) reacting trimellitic anhydride with an aliphatic diamine in the presence of 0 to 3 parts by weight of other carboxylic anhydrides and / or polycarboxylic acids per 100 parts by weight of the trimellitic anhydride to form one or more imide group-containing compounds having terminal carboxylic acid groups; b) optionally mixing the one or more imide group-containing compounds having terminal carboxylic acid groups with one or more aromatic dicarboxylic acid derivatives not containing imide groups selected from aromatic carboxylic acid anhydrides, aromatic dicarboxylic acids, aromatic halogenated dicarboxylic acids, and aromatic dicarboxylic acid dialkyl esters, wherein the molar ratio of the imide group-containing compounds to the aromatic dicarboxylic acid derivatives is at least 25:75; and c) esterifying the one or more imide group-containing compounds having terminal carboxylic acid groups and, if present, the one or more aromatic carboxylic acid derivatives, by reaction with one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / equivalent, wherein the imide-modified polyol composition has an acid number of 5 mg KOH / gram or less and a hydroxyl equivalent weight of 100 to 350 mg KOH / gram. The imide-modified polyol has a hydroxyl value of KOH / g and contains 0.65 to 2.30 moles of imide groups per kilogram of the imide-modified polyol composition. DETAILED DESCRIPTION OF THE INVENTION

[0004] With increasing global energy consumption, there is a strong need from end users of foam products for better thermal insulation performance and ease of processing and manufacturing, which is becoming increasingly difficult for the industry to achieve.

[0005] In addition, many polyurethane and polyisocyanurate foams are often required to be fire resistant, which requires the use of large amounts of halogenated flame retardants, which are under regulatory pressure in many jurisdictions.Therefore, it is desirable to reduce or even eliminate the use of these halogenated materials while maintaining the desired fire resistance in the foam.In summary, it would be advantageous to prepare a foam product that has both enhanced thermal insulation and good fire resistance.

[0006] One or more embodiments provide a method for producing an imide-modified polyol composition, the method comprising: a) reacting trimellitic anhydride with an aliphatic diamine in the presence of 0 to 3 parts by weight of other carboxylic anhydrides and / or polycarboxylic acids per 100 parts by weight of trimellitic anhydride to form one or more imide group-containing compounds having terminal carboxylic acid groups; b) optionally mixing the one or more imide group-containing compounds having terminal carboxylic acid groups with one or more aromatic dicarboxylic acid derivatives that do not contain imide groups selected from aromatic carboxylic acid anhydrides, aromatic dicarboxylic acids, aromatic halogenated dicarboxylic acids, and aromatic dicarboxylic acid dialkyl esters, wherein the molar ratio of the imide group-containing compounds to the aromatic dicarboxylic acid derivatives is at least 25:75; and c) then esterifying the one or more imide group-containing compounds having terminal carboxylic acid groups and, if present, the one or more aromatic carboxylic acid derivatives by reaction with one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / eq to produce the imide-modified polyol composition, wherein the imide-modified polyol composition has an acid number of 5 mg KOH / gram or less and a hydroxyl equivalent weight of 100 to 350 mg KOH / gram. The imide-modified polyol has a hydroxyl value of KOH / g and contains 0.65 to 2.30 moles of imide groups per kilogram of the imide-modified polyol composition.

[0007] One or more embodiments provide an imide-modified polyol composition produced by the aforementioned process.

[0008] One or more embodiments provide a method for preparing rigid isocyanate-based foam, comprising forming a reaction mixture and reacting the reaction mixture to produce a rigid isocyanate-based foam, the reaction mixture comprising: a) at least one aromatic polyisocyanate in an amount to provide an Isocyanate Index of 100 to 600; b) a polyol comprising at least 25 wt. % of the imide-modified polyol composition discussed herein and 0 to 75 wt. % of one or more non-imide-modified polyols, wherein the imide content of the polyol is 0.125 to 1.75 moles of imide groups per kilogram; c) at least one blowing agent; d) at least one halogenated and / or phosphorus-containing flame retardant; e) at least one foam-stabilizing surfactant; and f) at least one urethane and / or isocyanate trimerization catalyst.

[0009] The imide-modified polyol composition is produced by a process that includes forming an imide-group-containing compound having terminal carboxylic acid groups by reacting trimellitic anhydride with an aliphatic diamine.

[0010] The aliphatic diamine can have two primary amino groups. The aliphatic diamine can be a linear aliphatic diamine, a branched aliphatic diamine, a cyclic aliphatic diamine, or a heteroaliphatic diamine, as well as mixtures thereof. The heteroaliphatic diamine has heteroatoms such as oxygen, sulfur, and nitrogen interspersed between the alkylene groups having primary amino groups attached thereto. The aliphatic diamine lacking a carboxylic acid group can also lack other groups (other than amino groups) that are reactive with carboxylic acid, amine, or hydroxyl groups under the reaction conditions to produce the imide-modified polyol composition.One or more embodiments include aliphatic diamines, including conformational and positional isomers, such as 4,4'-methylenebis-cyclohexanamine, 2,2'-[oxybis(2,1-ethanediyloxy)]bis-ethanamine, 2,2'-oxybis-ethanamine, 3,3'-[oxybis(2,1-ethanediyloxy)]bis-1-propanamine, 1,4-butanediamine, 1,5-pentanediamine, 1,3-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,2-propanediamine, 2-methyl-1,3-propanediamine, 1,3-propanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 3,3'-[1,4-butanediylbis(oxy)]bis-1-propanamine, 1,4-cyclohexanedimethaneamine, 1,2-ethanediamine (which may also be referred to as ethylenediamine (ED)), 2,2'-(ethylenedioxy)bis(ethylamine) (which may also be referred to as 1,2-bis(2-aminoethoxy)ethane or diaminotriethylene glycol (DATEG)), 3,3'-[1,2-ethanediylbis(oxy)]bis-1-propanamine (which may also be referred to as ethylene glycol bis(3-aminopropyl)ether (EGAPE)), α-(2-aminomethylethyl)-ω-(2-aminomethylethoxy)-poly[oxy(methyl-1,2-ethanediyl)](polypropylene glycol diamine or polyoxypropylene diamine, or trade name JEFFAMINE D230), 2-methyl-1,5-pentanediamine (which may also be referred to as 2-methyl-1,5-diaminopentane (DYTEK A)), 1,3-cyclohexanedimethanamine (which may also be referred to as 1,3-bis(aminomethyl)cyclohexane (1,3-CHDMA)), 1,2-cyclohexanediamine (which may also be referred to as 1,2-diaminocyclohexane (1,2-CHDA)), 5-amino-1,3,3-trimethyl-cyclohexanemethanamine (which may also be referred to as isophoronediamine (IPDA)), or a combination thereof.One or more embodiments include aliphatic diamines, including conformational and positional isomers, such as 1,2-ethanediamine (which may also be referred to as ethylenediamine (ED)), 2,2′-(ethylenedioxy)bis(ethylamine) (which may also be referred to as 1,2-bis(2-aminoethoxy)ethane or diaminotriethylene glycol (DATEG)), 3,3′-[1,2-ethanediylbis(oxy)]bis-1-propanamine (which may also be referred to as ethylene glycol bis(3-aminopropyl)ether (EGAPE)), α-(2-aminomethylethyl)-ω-(2-aminomethylethoxy)-poly[oxy(methyl-1,2-ethanediyl)] (which may also be referred to as polypropylene glycol diamine or polyoxypropylene diamine or the trade name JEFFAMINE D230), 2-methyl-1,5-pentanediamine (2-methyl-1,5-diaminopentane (DYTEK A)), 1,3-cyclohexanedimethanamine (which may also be referred to as 1,3-bis(aminomethyl)cyclohexane (1,3-CHDMA)), 1,2-cyclohexanediamine (which may also be referred to as 1,2-diaminocyclohexane (1,2-CHDA)), 5-amino-1,3,3-trimethyl-cyclohexanemethanamine (which may also be referred to as isophoronediamine (IPDA)), or a combination thereof.

[0011] The imidization reaction is carried out in the presence of at most 3 parts by weight, at most 2 parts by weight, or at most 1 part by weight of other carboxylic anhydrides and / or polycarboxylic acids per 100 parts by weight of trimellitic anhydride. Such other carboxylic anhydrides or polycarboxylic acids, if present, may be, for example, impurities in trimellitic anhydride. The other carboxylic anhydrides and / or polycarboxylic acids may be absent. The near or complete absence of other carboxylic anhydrides and / or polycarboxylic acids may result in more defined and predictable products in the imidization reaction.

[0012] The trimellitic anhydride and aliphatic diamine may be combined in a ratio that provides 0.8 to 1.2, 0.9 to 1.1, or 0.95 to 1.05 equivalents of anhydride groups per equivalent of amine groups. One or more embodiments provide that the ratio is 0.98 to 1.02 or 0.99 to 1.01 equivalents of anhydride per equivalent of amine groups.

[0013] Trimellitic anhydride reacts with the amine group of an aliphatic diamine to form an amic acid intermediate, which then undergoes ring closure / dehydration by chemical and / or thermal means to form a diimide structure (e.g., an aromatic-aliphatic diimide) with the evolution of water. The diimide structure can be represented by structure (I), where Aliph represents an aliphatic group.

[0014] [ka]

[0015] The diimide contains two imide groups, which in turn provides two imide groups to the imide-modified polyol compositions discussed herein.

[0016] Aliphatic groups include straight chain alkylene having 2 to 18 carbon atoms, branched alkylene having 3 to 18 carbon atoms, alicyclic compounds having at least one ring and up to three rings with an independent ring size of 4 to 8 carbon atoms, -(CRR 1 ) n -[Z-(CR 2 R 3 ) n’ ] n’’ -Z-(CRR 1 ) n -heteroaliphatic alkylene of the form 1 , R 2 , R 3are independently H or a C1-C6 alkyl group, n and n' are independently integers from 2 to 4, n'' is an integer from 0 to 18, and each Z is independently a heteroatom; and mixtures thereof. One or more embodiments provide that the aliphatic group can be 1,2-ethane, 1,2-cyclohexane, 2-methyl-1,5-pentane, 1,3-dimethylenecyclohexane, 1,3,3-trimethylcyclohexanemethylene, poly(oxypropylene) having an average of up to four repeating units, 1,2-diethoxyethane, and 1,2-dipropoxyethane. The imidization reaction can be carried out at temperatures of, for example, 20°C to 180°C. Various pressures can be utilized (e.g., pressure sufficient to prevent the reactants from evaporating). Temperature and pressure conditions that allow water generated in the imidization reaction to evaporate or distill (including azeotropic distillation) and be removed as the reaction proceeds are preferred in some embodiments. An inert sweep gas may also be passed through the reaction vessel to remove water and / or water-containing azeotropes.

[0017] The imidization reaction can be carried out in a solvent suitable for trimellitic anhydride and aliphatic diamine. In some embodiments, the solvent is not reactive with either the starting materials or the reaction products. Examples of such non-reactive solvents include, for example, N,N-dimethylacetamide, N-methylpyrrolidinone, N,N-dimethylformamide, toluene, xylene, benzene, various C6-C24 hydrocarbons, mixtures thereof, and the like. The reaction can be carried out under reflux conditions for such non-reactive solvents, if used. The imide group-containing compound having terminal carboxylic acid groups produced by the imidization can be isolated from the non-reactive solvent and dried.

[0018] Alternatively, the imidization reaction can be carried out in the presence of a polyol having a hydroxyl equivalent weight of 30 to 500 g / eq, in which case the polyol can function as a solvent and / or reaction medium. When a polyol is utilized, the imidization reaction can be carried out in the absence of an effective amount of an esterification catalyst, i.e., a catalyst for the reaction of an alcohol with a carboxylic acid. In the absence of such a catalyst, little or no esterification of the terminal carboxyl groups occurs during the imidization process. The imide group-containing product can be isolated from the polyol and dried, although it is generally preferred not to do so, leaving the imide group-containing product in the polyol.

[0019] The diimide having terminal carboxylic acid groups obtained in the imidization step is then esterified by reaction with a polyol having a hydroxyl equivalent weight of 30 to 500 g / eq. The polyol may be present in or include any polyol present during the imidization reaction. Preferably, at least one polyol having a hydroxyl equivalent weight of at least 95 and up to 500 g / eq, e.g., 95 to 400, 95 to 350, or 150 to 250 g / eq, is reacted with the diimide having terminal carboxylic acid groups. In some embodiments, such polyols having a hydroxyl equivalent weight of at least 95 and up to 500 g / eq constitute at least 50%, at least 75%, at least 90%, or 100% of the total weight of the polyols having a hydroxyl equivalent weight of 30 to 500 g / eq. In other words, the polyol having a hydroxyl equivalent weight of at least 95 and up to 500 can represent a lower limit of 50%, 75%, or 90% to an upper limit of 100%, 99%, or 95% of the total weight of the polyol having a hydroxyl equivalent weight of 30 to 500 g / eq. The polyol having a hydroxyl equivalent weight of at least 95 and up to 500 g / eq is preferably difunctional and is preferably a polyether, particularly polyethylene glycol, poly(propylene glycol), or ethylene oxide / propylene oxide copolymer diol. Other useful polyols include diols such as ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, cyclohexanedimethanol, and neopentyl glycol. Polyols having three or more hydroxyl groups may form all or part of the polyol having an equivalent weight of 30 to 500, but if used, may constitute a small proportion thereof, such as up to 20% by weight, up to 10% by weight, or up to 5% by weight, for example, to avoid excessive branching and / or crosslinking.Examples of such polyols include glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, erythritol, triethanolamine, and polyethers having 3 to 6 hydroxyl groups per molecule and an equivalent weight of, for example, 100 to 500 g / equivalent.

[0020] Optionally, in one or more embodiments, the imide group-containing compound having a terminal carboxylic acid group is combined with one or more aromatic dicarboxylic acid derivatives that do not contain an imide group and are selected from aromatic carboxylic acid anhydrides, aromatic dicarboxylic acids, aromatic halogenated dicarboxylic acids, and aromatic dicarboxylic acid dialkyl esters, and an esterification step is simultaneously performed on the resulting mixture. The aromatic dicarboxylic acid derivative does not contain an imide group and preferably has a formula molecular weight of 250 g / mol or less. Examples of such aromatic dicarboxylic acid derivatives include phthalic anhydride, phthalic acid, isophthalic acid, terephthalic acid, dimethyl terephthalate, dimethyl isophthalate, dimethyl phthalate, terephthaloyl chloride, isophthaloyl chloride, phthaloyl chloride, etc., and mixtures of any two or more thereof. Preferred aromatic dicarboxylic acid derivatives are phthalic anhydride, phthalic acid, and isophthalic acid, especially phthalic anhydride. In such embodiments, the molar ratio of diimide to aromatic dicarboxylic acid derivative is at least 25:75 and can be any higher ratio up to 99.99:0.01. Examples of suitable ratios are at least 30:70 or at least 50:50. In some embodiments, the ratio may be at most 95:5, at most 90:10, at most 80:20, or at most 70:30.

[0021] Alternatively, an imide group-containing compound having a terminal carboxylic acid group can undergo an esterification step in the absence of an added aromatic dicarboxylic acid derivative to produce an imide-modified polyol. A portion of the starting polyol can remain unreacted during this step. In such embodiments, an aromatic dicarboxylic acid derivative can be subsequently added, and the resulting mixture can be subjected to esterification and / or transesterification conditions to produce the imide group-containing polyol composition discussed herein.

[0022] The ratio of polyol to imidization reaction product can be selected to provide 1.5 to 3 equivalents of hydroxyl groups per equivalent of carboxyl groups provided by the diimide and, if present, by the aromatic dicarboxylic acid derivative. For purposes of this calculation, an anhydride group counts as two carboxylic acid groups, and carboxylic acid alkyl ester and halide groups each count as one carboxylic acid group. The equivalent ratio can be at least 1.6, at least 1.75, or at least 1.9, and up to 2.5, up to 2.25, up to 2.10, or up to 2.05. If the equivalent ratio is greater than about 2, a portion of the polyol may remain unreacted during the esterification step.

[0023] The esterification reaction can be carried out in the presence of an esterification catalyst. Examples of esterification catalysts include Bronsted acids, such as sulfuric acid and p-toluenesulfonic acid; Lewis acids, such as SnCl, AlCl, and BF; tin(II) compounds, such as SnCl, and various tin dicarboxylates; organotin(IV) compounds, such as dialkyltin oxides, dialkyltin dicarboxylates, pyrone-coordinated Sn(II), Pb(II), Zn(II), and / or Hg(II) complexes; and various titanium compounds, such as titanium acetylacetonate, titanium(IV) oxyacetylacetonate, titanium diisopropoxide bis(acetylacetonate), tetraisopropyl titanium, triethanolamine titanate, titanium(IV) isobutoxide, and other organotitanium and organozirconium catalysts described in U.S. Pat. No. 3,056,818. Other examples of catalysts useful in the present disclosure are described, for example, in U.S. Pat. No. 10,619,000. The catalyst is used in a catalytically effective amount, for example, 10 to 10,000 parts by weight per million parts of the combined weight of the diimide, polyol, and any added aromatic dicarboxylic acid derivative.

[0024] The esterification reaction can be carried out at a temperature of 100°C to 270°C. One or more embodiments provide that the temperature is at least 180°C, at least 200°C, or at least 220°C. Various pressures can be utilized, and the pressure is generally sufficient to prevent the reactants from evaporating away, although temperature and pressure conditions that allow water and other volatile by-products of the esterification reaction to evaporate or distill and be removed as vapor as the reaction proceeds may be preferred. One or more embodiments provide that the pressure is about atmospheric, e.g., about 90 to 110 kPa. Subatmospheric pressures as low as 1 kilopascal to subatmospheric pressure can be used. The esterification reaction can be carried out in a solvent appropriate for the starting materials, such as those described above for the imidization reaction. The reaction can be carried out under reflux conditions for the solvent, if used, although it is preferred to carry out the esterification reaction in the absence of any solvent separate from the reactants. The reaction may be continued until the acid number drops to less than 5 mg KOH / g, less than 2 mg KOH / g, less than 1 mg KOH / g, or less than 0.5 mg KOH / g, as measured by potentiometric titration with a standardized 0.01 N potassium hydroxide solution. One or more embodiments specify that the acid number has a lower limit of 0.001 mg KOH / g, or 0.01 mg KOH / g. If a portion of the polyol volatilizes, it may be replenished by adding a corresponding amount of additional polyol, optionally followed by additional reaction under transesterification conditions.

[0025] The resulting imide-modified polyol composition contains one or more hydroxyl-terminated ester-containing reaction products of an imide group-containing compound and a polyol. If an aromatic dicarboxylic acid derivative is present during all or part of the esterification step, the composition also contains one or more hydroxyl-terminated ester-containing reaction products of the aromatic dicarboxylic acid derivative and a polyol. The imide-modified polyol composition may contain some amount of unreacted starting polyol. The imide-modified polyol composition has a hydroxyl number, measured according to ASTM E1899-16, of 100 to 350 mg KOH / g, 125 to 300 mg KOH / g, or 150 to 275 mg KOH / g. It contains 0.65 to 2.30 moles of imide groups per kilogram of imide-modified polyol composition. In some embodiments, the imide-modified polyol composition contains at least 0.75 or at least 1.00 moles of imide groups per kilogram, and in certain embodiments, at most 2.2 or at most 2.0 moles of imide groups per kilogram. An imide-containing compound prepared by reacting two moles of trimellitic anhydride with one mole of an aliphatic diamine produces two moles of imide groups.

[0026] The imide-modified polyol composition may have an average hydroxyl functionality ranging from 1.8 to 4, preferably from 1.8 to 3, more preferably from 1.8 to 2.5, or from 1.8 to 2.2. One or more embodiments provide that the imide-modified polyol composition is liquid at room temperature. In some instances, some crystals may form upon prolonged storage at room temperature, and these crystals typically disappear upon heating the imide-modified polyol composition. The imide-modified polyol composition may exhibit a viscosity of, for example, 1 to 300 Pa·s, 5 to 150, or 5 to 100 Pa·s, as measured according to ISO 3219 at 25°C and a shear rate of 10 sec-1. If crystals are formed in the imide-modified polyol composition, the viscosity is measured by heating the composition to 70°C to melt the crystals, cooling to 25°C within 4 hours, and then determining the viscosity.

[0027] The glass transition temperature (Tg) of the imide-modified polyol composition can be, for example, −10 to −80° C., or −25 to −65° C., with the midpoint temperature being Tg, measured according to ASTM E1356-08(2014).

[0028] Imide-modified polyol compositions are useful, for example, for producing isocyanate-based polymers. The isocyanate-based polymers contain urethane groups formed in the reaction between the hydroxyl groups of the imide-modified polyol composition and the isocyanate groups of the polyisocyanate. The isocyanate-based polymers may also contain other groups formed in the reaction of the isocyanate groups, such as urea, isocyanurate, biuret, allophanate, carbodiimide, and other groups. Some polymers are polyurethane-isocyanurate polymers, particularly foams, containing urethane and isocyanurate groups. The isocyanurate groups are formed in the trimerization reaction of three isocyanate groups.

[0029] Rigid isocyanate-based foams are produced by forming a reaction mixture and reacting the reaction mixture to produce the rigid isocyanate-based foam. The reaction mixture includes the imide-modified polyol composition discussed herein and at least one aromatic polyisocyanate. The aromatic polyisocyanate is provided in an amount to provide an isocyanate index of 100 to 600. The isocyanate index is 100 times the ratio of isocyanate groups to isocyanate-reactive groups (hydroxyl, primary or secondary amino, carboxylic acid, water, etc.) provided in the reaction mixture. For purposes of calculating the isocyanate index, water is considered to have two isocyanate-reactive groups. The isocyanate index in some embodiments is at least 125, at least 150, or at least 180.

[0030] The polyisocyanate may have, for example, an isocyanate equivalent weight of up to 300 g / eq. The isocyanate equivalent weight may be up to 250, up to 175, and in some embodiments, from 80 to 175 g / eq. When mixtures of polyisocyanate compounds are used, these equivalent weights apply to the mixture; individual polyisocyanate compounds in such mixtures may have isocyanate equivalent weights above, within, or below these ranges.

[0031] Examples of polyisocyanates include m-phenylene diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, hexahydrotoluene diisocyanate, naphthylene-1,5-diisocyanate, 1,3- and / or 1,4-bis(isocyanatomethyl)cyclohexane (including cis- and / or trans-isomers), methoxyphenyl-2,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, anate, hydrogenated diphenylmethane-4,4'-diisocyanate, hydrogenated diphenylmethane-2,4'-diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4',4''-triphenylmethane triisocyanate, polymethylene polyphenylisocyanate (PMDI), toluene-2,4,6-triisocyanate, and 4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate. Preferably, the polyisocyanate is diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, PMDI, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, or a mixture thereof. Diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, and mixtures thereof, collectively referred to as MDI, can all be used. A "polymeric MDI," which is a mixture of PMDI and MDI, can also be used. Toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, and mixtures thereof, collectively referred to as TDI, can all be used.

[0032] The imide-modified polyol composition of the present disclosure constitutes at least 25% by weight, or at least 50% by weight, of the polyols present in the foam-forming reaction mixture. In some embodiments, the imide-modified polyol composition constitutes at least 60% or at least 70% of the total weight of all polyols. It may constitute up to 100%, up to 95%, up to 90%, or up to 80% of the total weight of all polyols. The polyols in the foam-forming reaction mixture optionally contain one or more non-imide-modified polyols, provided that the imide content of the polyol is 0.125 to 1.75 moles, particularly 0.15 to 1.75 moles, or 0.30 to 1.50 moles of imide groups per kilogram of total weight of all polyols. If present, the non-imide-modified polyols may constitute, for example, 1 to 75%, 1 to 50%, 1 to 40%, 1 to 30%, 1 to 20%, 1 to 10%, or 1 to 5% of the total weight of all polyols (including the imide-modified polyol composition of the present disclosure).

[0033] Non-imide-modified polyols for the foam-forming reaction mixtures of the present disclosure may have, for example, an average nominal hydroxyl functionality ranging from 1.8 to 8, 1.8 to 6.0, 1.8 to 4.5, or 1.8 to 3.0, and an average hydroxyl number of 75 mg to 750 mg KOH / g.

[0034] Non-imide-modified polyols, when present, may include, for example, chain extenders, i.e., compounds that react difunctionally with isocyanate groups and have an equivalent weight per isocyanate-reactive group of less than 200, e.g., 30 to 125. Examples of chain extenders include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, 1,6-hexanediol, ethylenediamine, propylenediamine, and the like.

[0035] Other non-imide-modified polyols may include a crosslinker, i.e., a compound having three or more isocyanate-reactive groups and an equivalent weight per isocyanate-reactive group of less than 200, e.g., 30 to 125. Examples of crosslinkers include glycerin, trimethylolpropane, triethylolpropane, pentaerythritol, erythritol, triethanolamine, diethanolamine, mannitol, sucrose, urea, sorbitol, and the like.

[0036] Other non-imide-modified polyols include polyether polyols having an equivalent weight per isocyanate-reactive group greater than 75 g / equivalent. The equivalent weight can be, for example, up to 2000, up to 1000, up to 500, up to 400, or up to 300 g / equivalent. These polyols can have an average of 2 to 8, 2 to 4, or 2.5 to 4 isocyanate-reactive groups per molecule. Polyether polyols include, for example, homopolymers of propylene oxide, random polymers of at least 70 mol% propylene oxide and up to 30 mol% ethylene oxide, and random and / or block copolymers of homopolymers of ethylene oxide, at least 50 mol% ethylene oxide, and up to 50 mol% propylene oxide and / or butylene oxide.

[0037] Still other non-imide-modified polyols include polyester polyols and polycarbonate polyols. Non-imide-modified polyols, if present, may include at least one aromatic polyester polyol not present in the imide-modified polyol composition of the present disclosure. Such aromatic polyester polyols may have, for example, a hydroxyl equivalent weight of 150 to 400 g / eq and a hydroxyl functionality of 2 to 3, 2 to 2.7, or 2 to 2.5. If present, such other aromatic polyester polyols may constitute, for example, at least 5% or at least 10% and up to 75%, up to 35%, or up to 25% of the total weight of all polyols utilized.

[0038] The polyol present in the foam-forming reaction mixture may contain up to 45 wt.%, up to 30 wt.%, up to 25 wt.%, up to 15 wt.%, or up to 10 wt.% polyether polyol (other than the imide-modified polyol composition).

[0039] In some embodiments, polyethylene glycols having a number average molecular weight of up to 400 g / mol comprise 1-30% of the total weight of all polyols.

[0040] The foam-forming reaction mixture contains at least one blowing agent. The blowing agent may be or may include a chemical blowing agent that reacts under foaming reaction conditions to produce gas. Examples of chemical blowing agents include water and formic acid. In one or more embodiments, the foam-forming reaction mixture contains water in an amount of 0.1 to 3, or 0.2 to 2.5, 0.5 to 2.5, or 0.8 to 2.0 parts by weight per 100 parts by weight of total polyol in the foam-forming reaction mixture.

[0041] The blowing agent may be or include one or more physical (endothermic) blowing agents, which may be used alone or in combination with one or more chemical blowing agents (e.g., water). Examples of physical blowing agents include methyl formate, low-boiling hydrocarbons (e.g., heptane, hexane, n-pentane, iso-pentane, butane, cyclopentane, cyclohexane, etc., and mixtures thereof), low-boiling ketones such as acetone and methyl ethyl ketone, hydrochlorofluorocarbons (HCFCs) such as 1,1-dichloro-1-fluoroethane, hydrofluorocarbons (HFCs) such as 1,1,1,3,3-pentafluoropropane, hydrofluoroolefins (HFOs) such as trans-1,3,3,3-tetrafluoroprop-1-ene and 1,3,3,3-tetrafluoropropene, and mixtures thereof. Commercially available hydrofluoroolefin blowing agents include Solstice LBA and Solstice GBA, available from Honeywell; and Opteon 1100 and Opteon 1150, available from Chemours. Linear, branched, and / or cyclic C4-C6 alkanes, such as cyclopentane, isopentane, n-pentane, and neopentane, are particularly useful. One or more embodiments provide that the physical blowing agent is n-pentane or a cyclopentane / isopentane blend. When present, the physical blowing agent can be in an amount of 0.1 to 40 parts by weight per 100 parts of total polyol in the foam-forming reaction mixture.

[0042] The foam-forming reaction mixture preferably contains at least one halogenated and / or phosphorus-containing flame retardant that is not reactive toward isocyanate groups. Examples of non-reactive phosphorus-containing flame retardants include tris(1-chloropropyl)phosphate, triethyl phosphate, resorcinol bis(diphenyl phosphate), triphenyl phosphate, trimethyl phosphate, triphenylphosphine oxide, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide and derivatives, red phosphorus, inorganic phosphinates, aluminum phosphate, melamine orthophosphate, dimelamine orthophosphate, melamine pyrophosphate, melamine polyphosphate, oligomeric ethyl ethylene phosphate, dimethyl methyl phosphate, methyl ... Examples of suitable flame retardants include ethyl phosphonate, diethyl ethyl phosphonate, diethyl propyl phosphonate, tris(2-chloroethyl) phosphate, cyclic phosphonate, pentaerythritol phosphonate, cyclic neopentylthiophosphoric anhydride, metal phosphinates such as zinc diethyl phosphinate and aluminum diethyl phosphinate, tricresyl phosphate, t-butylphenyl phosphates including t-butylphenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, isodecyl diphenyl phosphate, and various phosphazene compounds. Polymeric or oligomeric phosphorus-containing compounds such as oligomeric alkyl phosphate esters (e.g., Levagard 2000 and Levagard 3000 from Lanxess) are also suitable. Phosphorus flame retardants containing one or more hydroxyl groups, such as Levagard 2100 and Levagard 4090N from Lanxess, and Fyrol 6 and VeriQuel R100 from ICL Industrial Products, can also be used. Halogenated flame retardants can be omitted. If used, the flame retardant can be present in an amount of 0.1 to 30 parts, 1 to 25 parts, 2 to 25 parts, or 5 to 25 parts per 100 parts by weight of total polyol in the foam-forming reaction mixture.

[0043] The foam-forming reaction mixture includes at least one surfactant (e.g., a foam-stabilizing surfactant). The surfactant can help stabilize the bubbles formed by the blowing agent during the foaming process until the polymer cures. Examples of suitable surfactants include silicone surfactants, such as polysiloxane polyoxyl alkylene block copolymers disclosed in U.S. Pat. Nos. 2,834,748, 2,917,480, and 2,846,458, and organic surfactants containing polyoxyethylene-polyoxybutylene block copolymers, such as those described in U.S. Pat. No. 5,600,019. Examples of such silicone surfactants are commercially available under the trade names Tegostab (Evonik Industries AG), Niax (Momentive), and Vorasurf (The Dow Chemical Company). Specific examples of useful surfactants include VORASURF DC 193, VORASURF RF 5374, VORASURF DC 5604, VORASURF SF 2937, VORASURF DC 5098, VORASURF 504, TEGOSTAB B8418, TEGOSTAB B8491, TEGOSTAB B8421, TEGOSTAB B8461, and TEGOSTAB B8462, NIAX L-6988, NIAX L-6642, and NIAX L-6633 surfactants. The amount of surfactant, if used, can be from 0.1 parts to 10.0 parts per hundred parts of total polyols present in the foam-forming reaction mixture.

[0044] The foam-forming reaction mixture contains one or more catalysts. The catalyst may include one or more urethane catalysts, which refer to compounds that catalyze either or both the water-isocyanate reaction and the alcohol-isocyanate reaction. Suitable catalysts include, for example, tertiary amines, cyclic amidines, tertiary phosphines, various metal chelates, acidic metal salts, strong bases, various metal alcoholates and phenolates, and metal salts of organic acids. Examples of metal-containing catalysts include salts of tin, bismuth, cobalt, and zinc. The catalysts include tertiary amine catalysts, cyclic amidines, zinc catalysts, and tin catalysts. Examples of tertiary amine catalysts include triethylamine, tributylamine, N-methylmorpholine, N-ethylmorpholine, N,N-dimethylbenzylamine, N,N-dimethylethanolamine, N,N-dimethylaminopropylamine, N,N,N',N'-tetramethyl-1,4-butanediamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'',N''-pentamethyldiethylenetriamine, N,N-dimethylcyclohexylamine, N,N-dimethylpiperazine, 1,4-diazobicyclo-2,2,2-octane, bis(dimethylaminoethyl)ether, triethylenediamine, and dimethylalkylamines in which the alkyl group contains 4 to 18 carbon atoms. Mixtures of these tertiary amine catalysts may also be used. When used, the tertiary amine catalyst may be present in an amount of, for example, 0.05 to 5 parts per 100 parts by weight of polyol in the foam-forming reaction mixture.

[0045] Examples of metal-containing urethane catalysts include tin(II) salts of organic carboxylic acids such as tin(II) diacetate, tin(II) ricinoleate, or tin(II) dioctoate, bismuth salts of organic carboxylic acids such as bismuth octoate, organotin compounds such as dimethyltin dilaurate, dibutyltin dilaurate, and other tin compounds of the formula SnRn(OR)4-n (where R is alkyl or aryl and n is 0 to 18), dialkyltin mercaptoates, and the like. The metal-containing urethane catalyst may be used in an amount such as 0.0015 to 0.25 parts by weight per 100 parts by weight of total polyol present in the foam-forming reaction mixture.

[0046] For example, reactive amine catalysts such as DMEA (dimethylethanolamine) or DMAPA (dimethylaminopropylamine), or amine-initiated polyols that act as autocatalytic polyols, can also be used to reduce VOCs (volatile organic compounds).

[0047] The foam-forming reaction mixture may contain at least one isocyanate trimerization catalyst. An isocyanate trimerization catalyst is a material that promotes the reaction of an isocyanate group with another isocyanate group to form an isocyanurate ring. Useful isocyanate trimerization catalysts include strong bases such as alkali metal phenolates, alkali metal alkoxides, alkali metal hydroxides, alkali metal carboxylates, and quaternary ammonium salts. The alkali metal may be sodium or potassium. Specific examples of such trimerization catalysts include sodium p-nonylphenolate, sodium p-octylphenolate, sodium p-tert-butylphenolate, sodium acetate, sodium 2-ethylhexanoate, sodium propionate, sodium butyrate, potassium analogs of any of the foregoing, trimethyl-2-hydroxypropylammonium carboxylate salts, N,N',N''-tris(3-dimethylaminopropyl)hexahydro-S-triazine, and the like. Examples of commercially available trimerization catalysts include Dabco K15, Polycat 46, TMR 2, TMR 18, etc., available from Evonik, among others, and DABCOK2097. The isocyanate trimerization catalyst may be present in a catalytic amount such as 0.05 to 10 parts by weight per 100 parts by weight of total polyols present in the foam-forming reaction mixture.

[0048] In addition to the aforementioned components, the foam formulation may contain various other optional ingredients, such as liquid nucleating additives, solid nucleating agents, Ostwald ripening inhibitor additives, reactive or non-reactive diluents, expandable graphite, pigments, rheology modifiers, emulsifiers, antioxidants, mold release agents, dyes, pigments and / or colorants such as titanium dioxide, iron oxide, chromium oxide, azo / diazo dyes, phthalocyanines, dioxazines, and carbon black; fillers or reinforcing agents such as fiberglass, carbon fiber, adhesive glass, mica, talc, and the like; and mixtures thereof.

[0049] Foams can be prepared by combining polyols, blowing agents, polyisocyanates, surfactants, flame retardants, and catalysts in the presence of various optional ingredients (if present) to form a foam-forming reaction mixture. The surfactants, catalysts, flame retardants, blowing agents, and various polyols can all be mixed together before combining with the polyisocyanate. Alternatively, they can be combined with the polyisocyanate individually (i.e., as separate streams) or formed into any submixture that is then combined with the polyisocyanate. The ingredients can be mixed at a temperature of 5 to 80°C. The ingredients can be mixed together using equipment such as, for example, spray equipment, low-pressure impact mixers, high-pressure impact mixers, static mixers, liquid dispensing guns or mixheads, or stirred vessels.

[0050] The reaction mixture is then reacted to form a foam. The process of the present disclosure does not require special processing conditions; therefore, typical processing conditions and equipment described in the art for producing rigid isocyanate-based foams are fully suitable. Generally, the components of the reaction mixture are mixed, and the thoroughly mixed foam-forming reactive composition is subjected to conditions sufficient to generate a foaming reaction. In most cases, the isocyanate compound will spontaneously react with the chemical blowing agent (if present) and polyol, even at room temperature (22°C). If necessary, heat can be applied to the reaction mixture to accelerate the curing reaction. This can be done by heating some or all of the components before combining them, by applying heat to the reaction mixture, or by a partial combination of each. The curing temperature can be, for example, 20°C to 150°C, or 30°C to 80°C. Curing can be continued until the reaction mixture has expanded and cured sufficiently to form a stable foam.

[0051] In some embodiments, the curing step occurs within a closed mold. In such processes, the reactive mixture is either formed within the mold itself or formed outside the mold and then injected into the mold where it cures. Thus, the expansion of the reactive mixture as it cures is limited by the interior surfaces of the mold, as well as the size and shape of the molded part.

[0052] In one or more embodiments, the curing step is carried out in a free-rise (or slabstock) process. In a free-rise process, the reaction mixture is poured into an open container so that expansion occurs in at least one direction (usually perpendicular) against the atmosphere or a lightweight surface (such as a film) that offers little resistance to the expansion of the foam. In a free-rise process, the reaction mixture expands essentially unrestrained in at least one direction, except by its own weight. A free-rise process may be carried out by forming the reaction mixture and dispensing it into a trough or onto a conveyor, where the reaction mixture expands and hardens.

[0053] In one or more embodiments, the foam-forming reaction mixture is dispensed between opposing panels (or onto a single panel), metered into layers, and cured to form a laminate material. This may be done, for example, in a double-belt laminator or similar device. Curing is conveniently accomplished by passing the opposing panels with the foam-forming reaction mixture layers applied through an oven that supplies heat to accelerate curing. This process is useful for producing sandwich panels for the construction or transportation industries.

[0054] The cured foam in some embodiments has a foam density, as measured by ISO 3886, of 20 to 200 kg / m 3 , 25 to 150 kg / m 3 , or 25 to 100 kg / m 3 .

[0055] The cured foam in some embodiments exhibits a smoke density of 60 or less, 50 or less, or 40 or less. Generally, a lower smoke density indicates better combustion performance. One or more embodiments provide that the smoke density can have a lower limit of, for example, 0, 3, or 5. According to ASTM E 662, using an NBS smoke chamber, the smoke density can be 25 kW / m 2 The smoke density produced when each foam sample was exposed to a flame at a heat flux of 1000 psi was measured.

[0056] The cured foams in some embodiments exhibit advantageously low thermal conductivity or k-factor (10°C average plate temperature). In some embodiments, the k-factor is 19.5 mW / mK or less, 19.2 mW / mK or less, or 19.0 mW / mK or less. In some embodiments, cured foams with a hydrofluoroolefin (HFO) blowing agent such as SOLSTICE LBA can achieve thermal conductivities of 18.0 mW / mK or less, 17.5 mW / mK or less, even 17.0 mW / mK or less, or even 16.5 mW / mK or less. Rigid isocyanate-based foams of this embodiment can have thermal conductivities greater than 15.0 mW / mK. Foams with lower thermal conductivities provide improved thermal insulation performance.

[0057] The foams of the present disclosure are useful in various types of thermal insulation applications, such as building and construction applications, applications such as walk-in coolers, chilled shipping containers, cold storage, etc. The imide-containing polyols can be used to make non-cellular isocyanate-based polymers useful in, for example, coatings, adhesives, and electronics.

[0058] The following examples are offered for illustrative purposes and are not intended to limit the scope of the invention. All parts and percentages are by weight unless otherwise indicated. [Example]

[0059] The imide-modified polyol composition of Example 1-P (EX 1-P) was prepared as follows: 2,2'-(ethane-1,2-diyl)bis(1,3-dioxoisoindoline-5-carboxylic acid) was prepared as follows: 1-Methyl-2-pyrrolidinone (240 mL, NMP) and toluene (50 mL in the flask and 20 mL in the Dean-Stark trap) were added to a vessel (a magnetically stirred, three-necked, 500 mL round-bottom flask equipped with a N2 inlet / outlet, a stopper, and a Dean-Stark trap with a condenser), the toluene was refluxed, and the collected water was drained through the trap. Trimellitic anhydride (64.04 g, 0.3333 mol) was added to the vessel in four equal portions over 1.25 hours. Ethylenediamine (10.01 g, 0.1666 mol, EDA) was added dropwise to the vessel over 20 minutes under positive N2 via an attached pressure-equalizing addition funnel. The contents of the vessel were warmed to 60°C and maintained for 1 hour. The apparatus was switched to an N2 sweep, and the toluene was refluxed for 3 hours, collecting the water that drained through the trap, followed by removal of most of the toluene through the trap. The contents of the vessel were cooled to approximately 20°C, then chilled in ice water, and the solid product was collected by filtration. The product was washed with 2 x 150 mL of methanol. The product was dried in a vacuum oven at 80°C for approximately 12 hours. The product (2,2'-(ethane-1,2-diyl)bis(1,3-dioxoisoindoline-5-carboxylic acid)) was recrystallized from hot N,N-dimethylacetamide (177 g). Upon cooling, the solid product was collected by filtration, washed with approximately 3 x 50 mL of methanol, and dried sequentially in a vacuum oven at 80°C and then 115°C to constant weight. Yield = 51.4 grams, melting point 367°C.

[0060] Polyethylene glycol 200 (83.77 g, 0.4168 mol), diethylene glycol (7.75 g, 0.0730 mol), phthalic anhydride (18.14 g, 0.1224 mol), and 2,2'-(ethane-1,2-diyl)bis(1,3-dioxoisoindoline-5-carboxylic acid) (50.00 g, 0.1224 mol) were added to a vessel (a four-neck, 500 mL round-bottom flask, an N inlet adapter inserted with an overhead stirrer, and a stopper on the remaining neck). The apparatus was degassed with three N / vacuum (100 Torr) cycles and maintained under a N sweep using a Dean-Stark trap and condenser attached to the flask outlet. The apparatus was insulated, and TYZOR AA105 (0.0166 g) was charged to the flask at 102°C while the flask was stirred and warmed from room temperature to an initial set point of 200°C over 2 hours. The flask was held at 200°C for 1 hour, then warmed / held at 210°C for 1 hour, and warmed / held at 220°C for 6 hours, collecting and venting the distillate. The Dean-Stark trap and condenser were removed, and the apparatus was cooled to 200°C under positive N. Make-up DEG (6.3 g) was added to the flask to make up the excess distillate, followed by a 1-hour hold at 200 / 180°C before cooling and transferring. The final product has a viscosity (η) of 31.2 Pa.s at 25°C, a GPC molecular weight of Mn 646, Mw 1081, a polydispersity index of 1.67, a hydroxyl number (OH#) of 197 mg KOH / gram (theoretical 180 mg KOH / g), an acid number (acid#) of 0.15 mg KOH / g, and a glass transition (Tg) of -39°C.

[0061] Example 2-P (imide-modified polyol composition) was prepared as follows: Polyethylene glycol 200 (150.53 g, 0.74891 mol), diethylene glycol (13.93 g, 0.1313 mol), and ethylenediamine (13.20 g, 0.2199 mol) were added to a vessel (a four-neck, 500 mL round-bottom flask, an N2 inlet adapter inserted with an overhead stirrer, and a stopper on the remaining neck). The flask was degassed three times by cycling between 200 Torr and atmospheric N2. The flask was placed under a gentle N2 sweep through a Dean-Stark trap and condenser attached to the flask outlet. The apparatus was insulated. The flask was placed under positive N2 and trimellitic anhydride (84.52 g total, 0.4399 mol) was added in three equal portions to the stirred flask. The first portion was added at 50°C, followed by a mild exotherm. After 20 minutes, the second portion was added at 57°C and the set point was increased to 75°C. After 30 minutes, the third portion was added at 75°C and the set point was increased to 95°C and held there for 1.25 hours. The reaction mixture was then ramped to 140°C under a gentle N2 sweep and held there for 3 hours. The reaction mixture was then warmed to 160°C and held there for 2 hours while collecting distillate. The reaction mixture was cooled to 95°C along with phthalic anhydride (32.60 g, 0.02201 mol) and TYZOR AA105 (0.0860 g) and added to the flask. The flask was heated with stirring to a set point of 200°C over 0.75 hours, held for 1 hour, then heated to 210°C and held for 1 hour before being cooled to room temperature. The flask was reheated to 220°C over 1.5 hours (additional charge of TYZOR AA105 (0.0489 g) made at 90°C) and held at 220°C for 6 hours, with distillate collected and vented. The Dean-Stark trap and condenser were removed, the apparatus cooled to 200°C under positive N, makeup diethylene glycol (2.25 g) was added to the flask to make up excess distillate, and then held at 200 / 180°C for 1 hour before being cooled and transferred.The final product has a viscosity (η) of 43.8 Pa.s at 25°C, a GPC molecular weight of Mn 677, Mw 1243, a polydispersity index of 1.84, a hydroxyl number (OH#) of 176 mg KOH / gram (theoretical 180 mg KOH / g), an acid number (acid#) of 0.17 mg KOH / g, and a glass transition (Tg) of -34°C.

[0062] Example 3-P (imide-modified polyol composition) was prepared as follows: Polyethylene glycol 200 (333.12 g, 1.6573 mol), diethylene glycol (31.04 g, 0.2925 mol), and ethylenediamine (14.63 g, 0.2438 mol) were added to a vessel (a four-neck, 1000 mL round-bottom flask, an N2 inlet adapter inserted with an overhead stirrer, and a stopper on the remaining neck). The flask was degassed three times by cycling between 200 Torr and atmospheric N2. The flask was placed under a gentle N2 sweep through a Dean-Stark trap and condenser attached to the flask outlet. The apparatus was insulated. The flask was placed under positive N2 and trimellitic anhydride (93.65 g total, 0.4874 mol) was added in three equal portions to the stirred flask. The first portion was added at 51°C with a mild exotherm after 25 minutes, the second portion was added at 56°C with a mild exotherm after 20 minutes, the third portion was added at 69°C with a set point of 70°C after 40 minutes, and the set point was increased and held at 95°C for 50 minutes. The reaction mixture was then ramped to 140°C under a gentle N2 sweep and held for 3 hours, and the reaction mixture was warmed and held at 160°C for 1 hour while collecting distillate. TYZOR AA105 (0.1079 g) was added to the flask and the reaction mixture was warmed and held at 220°C for 3.5 hours. The reaction mixture was cooled with phthalic anhydride (108.30 g, 0.73115 mol) and TYZOR AA105 (0.1244 g) and added to the flask at 96°C. The flask was warmed with stirring to a set point of 200°C over 0.8 hours, held at 200°C for 1 hour, then heated to 220°C and held for 6.5 hours before cooling to 200°C and collecting the distillate and venting. The Dean-Stark trap and condenser were purged under positive N2 and makeup diethylene glycol (6.58 g) was added to the flask to replace excess distillate, then held at 200 / 180°C for 1 hour before cooling and transferring.The final product has a viscosity (η) of 6.54 Pa.s at 25°C, a GPC molecular weight of Mn 595, Mw 947, a polydispersity index of 1.59, a hydroxyl number (OH#) of 212 mg KOH / gram (theoretical 199 mg KOH / g), an acid number (acid#) of 1.40 mg KOH / g, and a glass transition (Tg) of -47°C.

[0063] The imide-modified polyol compositions of Examples 4-P to 13-P were prepared using the materials shown in Tables 1 to 3 in the same manner as in Example 3-P.

[0064] TYZOR AA105 is titanium acetylacetonate (100% active), Dytek A is 2-methyl-1,5-pentanediamine, JEFFAMINE D230 is a polyoxypropylene diamine with a nominal molecular weight of 230, 1,3-CHDMA is 1,3-bis(aminomethylene)cyclohexane (mixture of cis / trans isomers), 1,2-CHDA is 1,2-diaminocyclohexane (mixture of cis / trans isomers), IDPA is isophoronediamine (mixture of cis / trans isomers), and EGAPE is ethylene glycol bis(3-aminopropyl)ether.

[0065] A number of properties were measured for the imide-modified polyol compositions. Glass transition temperature (Tg) was determined according to ASTM E1356-08, taking the midpoint temperature as Tg. Hydroxyl number was determined according to ASTM E1899-16. Acid number was determined by potentiometric titration with a standardized 0.01 N potassium hydroxide solution according to ASTM D664-18. Number average molecular weight (Mn), weight average molecular weight (Mw), and polydispersity index (PDI) = Mw / Mn were determined according to ASTM D5296-19, utilizing polyethylene glycol calibration standards and uninhibited tetrahydrofuran solvent.

[0066] [Table 1]

[0067] [Table 2]

[0068] [Table 3]

[0069] [Table 4]

[0070] The data in Table 4 show that each of Examples 1-P through 13-P has a Tg of -20°C or less, a number average molecular weight (Mn) of 300 Pa-s or less at 25°C, and a hydroxyl number of 100 to 350 KOH / g.

[0071] Foams (Examples 1-F through 17-F, and Comparative Examples AF through CF) were made from the formulations described in Tables 5, 6, 7, 10, and 13. For each foam, the polyol, surfactant, water, and catalyst were mixed using a laboratory mixer. The imide-modified polyol composition was placed in a 70°C oven overnight, then mixed with the other polyols at room temperature while still warm and then cooled to room temperature (18-25°C). The physical blowing agent (pentane mixture or SOLSICE LBA) was then mixed, followed by the polyisocyanate. The resulting reaction mixture was mixed at high speed for 5 seconds and then immediately poured into a vertically oriented 30 cm x 20 cm x 5 cm mold (preheated to 55°C). The reaction mixture was allowed to react in the mold for 20 minutes, at which point the resulting foam was demolded.

[0072] Polyol A is an aromatic polyester polyol with a functionality of 2.0 and a hydroxyl number of 220 mg KOH / g.

[0073] Polyol B is an aromatic polyester polyol with a functionality of 2.4 and a hydroxyl number of 315 mg KOH / g.

[0074] Polyol C is polyethylene glycol 200.

[0075] Triethyl phosphate is a flame retardant. The urethane catalyst is a commercially available 1,1,4,7,7-pentamethyldiethylenetriamine product. The trimerization catalyst is a commercially available material, DABCO K2097, available from Evonik. The pentane blend is an 80 / 20 mixture of cyclopentane and isopentane. The silicone surfactant is commercially available as VORASURF SF 2937. PMDI is a polymeric MDI product with an average isocyanate functionality of 3.0 and an isocyanate equivalent weight of 136.5. Numerous properties were determined for the foam. Results are reported in Tables 8, 9, 11, 12, and 14.

[0076] Cream time and gel time were determined according to the test procedures described in ASTM D7487(2013). Cream time was observed visually, gel time was assessed by periodically touching the surface of the curing reaction mixture with a wooden tongue depressor (gel time is the time after the polyisocyanate and formulated polyol composition are mixed that a string begins to form when the wooden tongue depressor is pulled away), tack-free time is the time when the surface of the foam is no longer tacky to the touch, and free-rise foam density was measured according to ASTM D 6226. Fresh foam samples were conditioned overnight in air at room temperature before being taken for property testing. K-factor (thermal conductivity) was measured according to ASTM C518, and foam core density was determined by weighing the K-factor test specimen and measuring the physical dimensions of the K-factor board. Compressive strength was measured according to ASTM D1621.

[0077] [Table 5]

[0078] [Table 6]

[0079] [Table 7]

[0080] [Table 8]

[0081] [Table 9]

[0082] The data in Tables 8 and 9 demonstrate advantageous thermal insulation performance properties while maintaining desirable fire performance properties. The data in Tables 8 and 9 demonstrate desirable mechanical properties. Additionally, the data in Table 9 demonstrate a reduction in k-factor for each of Examples 1-F through 12-F compared to Comparative Examples A-F.

[0083] [Table 10]

[0084] [Table 11]

[0085] [Table 12]

[0086] [Table 13]

[0087] [Table 14]

[0088] The data in Tables 11 and 12 demonstrate advantageous thermal insulation performance properties while maintaining desirable fire performance properties. The data in Tables 11 and 12 demonstrate desirable mechanical properties. Additionally, the data in Table 12 demonstrates a reduction in k-factor for each of Examples 13-F through 16-F compared to both Comparative Examples A-F and Comparative Examples B-F.

[0089] The data in Table 14 demonstrate advantageous thermal insulation performance characteristics. Additionally, the data in Table 14 demonstrates a reduction in the k-factor for Example 17-F compared to Comparative Examples C-F.

Claims

1. 1. A method for producing an imide-modified polyol composition, comprising: a) forming one or more imide group-containing compounds having terminal carboxylic acid groups by reacting trimellitic anhydride with an aliphatic diamine in the presence of 0 to 3 parts by weight of other carboxylic anhydrides and / or polycarboxylic acids per 100 parts by weight of trimellitic anhydride; b) optionally mixing one or more imide group-containing compounds having terminal carboxylic acid groups with one or more aromatic dicarboxylic acid derivatives not containing imide groups selected from aromatic carboxylic acid anhydrides, aromatic dicarboxylic acids, aromatic halogenated dicarboxylic acids, and aromatic dicarboxylic acid dialkyl esters, wherein the molar ratio of the imide group-containing compounds to the aromatic dicarboxylic acid derivatives is at least 25:75; c) then esterifying the one or more imide group-containing compounds having terminal carboxylic acid groups and, if present, the one or more aromatic carboxylic acid derivatives by reaction with one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / eq; The method of claim 1, wherein the imide-modified polyol composition has an acid number of 5 mg KOH / gram or less, a hydroxyl number of 100 to 350 mg KOH / g, and contains 0.65 to 2.30 moles of imide groups per kilogram of imide-modified polyol composition.

2. 2. The method of claim 1, wherein the aliphatic diamine is selected from 1,2-ethanediamine, 2,2'-(ethylenedioxy)bis(ethylamine), 3,3'-[1,2-ethanediylbis(oxy)]bis-1-propanamine, α-(2-aminomethylethyl)-ω-(2-aminomethylethoxy)-poly[oxy(methyl-1,2-ethanediyl)], 2-methyl-1,5-pentanediamine, 1,3-cyclohexanedimethaneamine, 1,2-cyclohexanediamine, 5-amino-1,3,3-trimethyl-cyclohexanemethanamine, or combinations thereof, including conformational and positional isomers.

3. 3. The method of claim 1 or 2, wherein at least 50 wt. % of the one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / eq have a hydroxyl equivalent weight of 95 to 500.

4. 4. The process of claim 1, wherein a) is carried out in the presence of said one or more polyols having a hydroxyl equivalent weight of from 30 to 500 g / eq and in the absence of a catalytic amount of an esterification catalyst.

5. 5. The method of any one of claims 1 to 4, wherein b) is not performed and the product obtained in c) is mixed with one or more aromatic dicarboxylic acid derivatives that do not contain imide groups selected from aromatic carboxylic acid anhydrides, aromatic dicarboxylic acids, aromatic halogenated dicarboxylic acids, and aromatic dicarboxylic acid dialkyl esters, and the resulting combination is subjected to esterification and / or transesterification conditions to produce the imide-modified polyol composition.

6. 5. The method according to claim 1, wherein b) is carried out and the imide-modified polyol composition is obtained in c), wherein the imide-modified polyol composition comprises a mixture of an imide-modified polyol and a polyester polyol corresponding to the esterification product of the one or more aromatic dicarboxylic acid derivatives and the one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / eq.

7. An imide-modified polyol composition produced by the process of any one of claims 1 to 6.

8. 8. The imide-modified polyol composition of claim 7, comprising a mixture of an imide-modified polyol and a polyester polyol corresponding to the esterification product of said one or more aromatic dicarboxylic acid derivatives with said one or more polyols having a hydroxyl equivalent weight of 30 to 500 g / eq.

9. 1. A method for preparing rigid isocyanate-based foam, comprising forming a reaction mixture and reacting the reaction mixture to produce the rigid isocyanate-based foam, wherein the reaction mixture comprises: a) at least one aromatic polyisocyanate in an amount to provide an Isocyanate Index of 100 to 600; b) a polyol comprising at least 25 wt. % of the imide-modified polyol composition of claim 7 or 8 and 0 to 75 wt. % of one or more non-imide-modified polyols, the imide content of the polyol being 0.125 to 1.75 moles of imide groups per kilogram; c) at least one blowing agent; d) at least one halogenated and / or phosphorus-containing flame retardant; e) at least one foam stabilizing surfactant; and f) at least one urethane and / or isocyanate trimerization catalyst.

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