RIGID POLYURETHANE FOAMS COMPRISING A SILOXANE-RICH NUCLEATING AGENT

Abstract

The present technology provides a method for manufacturing a polyurethane foam with low thermal conductivity from a foam formulation comprising a polyol, an isocyanate, a polyurethane catalyst, a surfactant, water, and a siloxane-rich composition. The siloxane-rich composition can act as a nucleating agent to reduce the cell size of the foams and can reduce their thermal conductivity.

Description

RIGID POLYURETHANE FOAMS COMPRISING A SILOXANE-RICH NUCLEATING AGENT CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority and the benefit of U.S. Temporary Application 62 / 769,060 entitled “Rigid Polyurethane Foams Comprising a Siloxane-Rich Nucleating Agent” filed on November 19, 2018, the disclosure of which is incorporated herein by reference in its entirety. FIELD OF INVENTION

[0002] This technology generally relates to polyurethane foam compositions and foams made from such compositions. More particularly, this technology relates to rigid or semi-rigid polyurethane foams that employ siloxane-rich compounds of a particular molecular weight as nucleating agents. BACKGROUND OF THE INVENTION

[0003] Rigid polyurethane foams are divided into two categories: polyurethane rigid foam (PUR) and polyisocyanurate rigid foam (PIR). PUR rigid foams are made with a low excess of isocyanate and predominantly contain urethane and urea bonds formed from the isocyanate reaction. PIR rigid foams are made with a large excess of isocyanate, resulting in a significant number of isocyanurate bonds from the isocyanate trimerization reaction, in addition to the urethane and urea bonds. Both types of foam are widely used as insulation materials in the construction industry and for domestic and commercial cooling. These foams exhibit excellent insulation characteristics.

[0004] Conventional rigid polyurethane foam, such as may be used in insulation applications, is generally prepared by the reaction of at least one polyol with at least one isocyanate in the presence of suitable catalysts, surfactants, chemical and / or physical swelling agents and optionally other additives such as flame retardants or other processing additives or foam-enhancing additives.

[0005] Silicone-polyether copolymers are widely used as surfactants in such rigid polyurethane foam formulations. Attempts have been made to optimize these types of copolymers to improve or maximize the nucleating effect without compromising other foam properties. An opportunity exists to develop a rigid polyurethane foam with improved thermal conductivity properties for use in insulation applications. BRIEF DESCRIPTION OF THE INVENTION

[0006] The present technology provides a siloxane-based additive composition for use in semi-rigid or rigid polyurethane foam formulations to provide improved thermal conductivity.

[0007] In one aspect, the present technology provides a rigid polyurethane or polyisocyanurate foam composition comprising a polyol or a mixture thereof, an isocyanate, a polyurethane catalyst or a mixture thereof, a surfactant, a siloxane-rich composition, a swelling agent being either water, a physical swelling agent or a mixture thereof, or a combination thereof, optionally a co-chemical swelling agent or a mixture thereof, optionally a flame retardant additive or a mixture thereof, and optionally other processing additives. It has been found that the use of siloxane-rich materials of specific molecular weight can serve as nucleating agents when used in combination with conventional rigid foam surfactants, and especially those based on silicone polyether copolymers.The applicant has found that by using these siloxane-rich materials of a certain molecular weight and / or molecular weight distribution, a positive nucleating effect can be achieved in the initial mixing stage without leading to defoaming or lack of cell size control in a subsequent reaction stage, thus providing foams with low cell size, which leads to low thermal conductivity of the foam.

[0008] In one embodiment, a composition comprising a siloxane-rich compound of formula: is provided MWWVdQe (II) where M3 is a trialkyl end cap unit R3R4R5SIOi / 2-; D3 is a dialkyl unit -Oi / 2R6R7SIO 1 / 2—; D4 is an alkyl unit - Oi / 2R8R9S¡O1 / 2—; T is - Oi / 2Si(Oi / 2 -)2 R10; Q is Si(Oi / 2-)4; R3, R4, R6, R7, R8, and R10 are independently fluorine, phenyl, or C1 to CIO alkyl groups, eventually becoming partially or completely substituted fluorine or phenyl; R5 is fluorine; phenyl; or C1 to C10 alkyl groups optionally partially or completely substituted with fluorine or phenyl; or -R11-Om-(CH2-CH2-O)q(CH2-CH(CH3)-O)P-R12; R9es -R11-Om-(CH2-CH2-O)q(CH2-CH(CH^ R11 is hydrocarbon group C1 to C10; R12 is hydrogen, phenyl, fluorine, or a C1-C8 hydrocarbon group, in which fluorine or phenyl are partially or completely substituted and optionally interrupted by urethane, urea, or carbonyl groups. a and b are independently from 0 to 30; c, d, and y are independently from 0 to 5; m is 0 or 1; q and p are independently from 0 to 10; provided that b + c is at least 1; provided that the siloxane-rich component has a silicon content of at least 25% by weight. occncn / 1 ?n7 / □ / yl

[0009] In one modality, the compound or molecule of between 200 and 3000 daltons.

[0010] In one modality, the compound or molecule of between 300 and 2500 daltons.

[0011] In one embodiment, the siloxane-rich compound or mixture has a molecular weight number of between 450 and 2000 daltons.

[0012] In one embodiment of the composition of any of the above embodiments, the siloxane-rich compound or mixture has a silicon content above 28% by weight.

[0013] In one embodiment of the composition of any of the above embodiments, the siloxane-rich compound or mixture has a silicon content above 25% by weight and up to approximately 32% by weight.

[0014] In one embodiment of the composition of any of the above embodiments, the siloxane-rich compound or mixture has an average of 2 or fewer reactive groups per molecule that can react with isocyanate.

[0015] In one embodiment of the composition of any of the above embodiments, the siloxane-rich compound or mixture has on average less than 2 or no reactive groups that can react with isocyanate.

[0016] In one embodiment of the composition of any of the above embodiments, the subscript a of the siloxane-rich compound is at least equal to 1.

[0017] In one modality of the composition of any of the above modalities, the subscript a is from 1 to 30; 2 to 20; or 2 to 10.

[0018] In one embodiment of the composition of any of the above embodiments, the siloxane-rich composition is based on a molecular weight distribution containing 2.5% or less of siloxane-based species having a molecular weight below 400.

[0019] In one embodiment of the composition of any of the above embodiments, the siloxane-rich composition is based on a molecular weight distribution containing 2.5% or less of siloxane-based species having an average molecular weight number below 400; below 350; below 300; or below 250.

[0020] In one embodiment of the composition of any of the above embodiments, the siloxane-rich composition contains approximately 5% or less of cyclic siloxane species containing 3 to 6 siloxane groups, commonly called D3, D4, and D6; 3.5% or less; 2.5% or less; 1% or less; or 0.5% or less.

[0021] In one aspect, a foam formulation comprising a polyol; an isocyanate; a catalyst; a surfactant; a physical swelling agent; and a siloxane-rich composition is provided according to any of the above embodiments.

[0022] In another aspect, a process is provided for producing a polyurethane foam by reacting the different components of a formulation comprising: a polyol; an isocyanate; a catalyst; a surfactant; a physical swelling agent; and a siloxane-rich composition according to any of the above embodiments.

[0023] In one embodiment, the siloxane-rich composition or mixture is used in an amount of at least 0.02% by weight of the total weight of the components in the formulation excluding physical swelling agents.

[0024] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is present in an amount of at least 0.03% by weight of the total weight of the components in the formulation excluding physical swelling agents.

[0025] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is present in an amount of at least 0.05% by weight of the total weight of the components in the formulation excluding physical swelling agents.

[0026] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is present in an amount of 3% by weight or less of the total weight of the components in the formulation excluding physical swelling agents.

[0027] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is present in an amount of approximately 0.05% by weight to 3% by weight of the total weight of the components in the formulation excluding physical swelling agents.

[0028] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is added to a premix formulated to be mixed with an isocyanate component to produce a polyurethane foam used as a thermal insulation material.

[0029] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is added as a separate component in a foam dispensing unit to produce a polyurethane foam used as a thermal insulation material.

[0030] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is added to an isocyanate component to be mixed with isocyanate-reactive ingredients to produce a polyurethane foam used as a thermal insulation material.

[0031] In one embodiment of the process of any of the above embodiments, the siloxane-rich composition or mixture is added to the polyurethane foam formulation in addition to a surfactant, which optionally contains siloxane, the portion of such surfactant containing siloxane, if present, having a silicon content of less than 25% and an average molecular weight number above 2000 daltons.

[0032] In one embodiment of the process of any of the above embodiments, the polyol is selected from polyester polyols, polyether polyols, polycarbonate polyols, polythioether polyols, polycaprolactones, brominated polyether polyols, acrylic polyols, or a combination of two or more of the same.

[0033] In one embodiment of the process of any of the above embodiments, the catalyst package is made of a tertiary amine that provides swelling and gelling catalytic activity and optionally a trimerization catalyst that provides isocyanurate catalytic activity.

[0034] In one embodiment of the process of any of the above embodiments, the physical swelling agent is selected from hydrocarbons and in particular pentane and any isomeric mixture of hydrofluorocarbons, hydrofluoroolefins, hydrochlorofluorocarbons, hydrochlorofluoroolefins and any combination thereof.

[0035] In one embodiment of the process of any of the above embodiments, the process forms a rigid or semi-rigid polyurethane foam. In one embodiment, the rigid or semi-rigid polyurethane foam has a density of between 10 and 100 kg / m3 and an isocyanate index of between 100 and 500.

[0036] In one embodiment, the foam is used as a thermal insulation material.

[0037] In one embodiment, the foam has an initial thermal conductivity of approximately 23 mW / m · K or less at an average temperature of 0 to 30°C.

[0038] In yet another aspect, an article comprising polyurethane foam formed from the process is provided.

[0039] In one aspect, a polyurethane or polyisocyanurate foam is provided formed from the composition of any of the above forms.

[0040] In one embodiment, the foam isocyanate composition is selected from an aromatic polyisocyanate, an aliphatic polyisocyanate, or any combination thereof.

[0041] In one aspect, an article comprising polyurethane or polyisocyanurate foam of any of the above forms is provided.

[0042] In one aspect, a method is provided for forming a polyurethane or polyisocyanurate foam comprising reacting the composition of any of the above forms. DETAILED DESCRIPTION OF THE INVENTION

[0043] The present technology provides an additive composition for use in a foaming formulation and foams made from such a formulation. The foam formulations comprise: (a) a polyol component; (b) an isocyanate component; (c) a catalyst component; (d) a surfactant; and (e) a siloxane-rich composition. The use of siloxane-rich compositions provides a foam with desirable properties, including, for example, low thermal conductivity. Without adhering to any particular theory, siloxane-rich compositions can serve as a good nucleating agent and enable control or provide a foam with desirable properties, including, for example, low thermal conductivity.

[0044] The polyol component is not particularly limited and may be chosen as desired for a particular purpose or application. In various embodiments, the polyol may be selected from polyester polyols, polyether polyols, polycarbonate polyols, hydroxyl-terminated polyolefin polyols, etc., or a combination of two or more of these. The polyols may be, for example, polyester diols, polyester triols, polyether diols, polyether triols, etc. Alternatively, the polyol may be selected from the group of polythioether polyols, polycaprolactones, brominated polyether polyols, acrylic polyols, etc., or a combination of two or more of these. When high-functionality polyether polyols are used, the high-functionality polyether polyol may have a functionality of approximately 3 to 6.Polyols such as sucrose or sorbitol starters can be mixed with glycols or low-functionality amines to bring the functionality of the polyols to the range of approximately 3.5 to 5.

[0045] Additionally, particularly suitable polyols include aromatic polyester polyol. Aromatic polyester polyol can be prepared from substantially pure reactant materials or from more complex raw materials such as polyethylene terephthalate. Furthermore, dimethyl terephthalate (DMT) process waste can be used to form aromatic polyester polyol.

[0046] The aromatic polyester polyol may comprise halogen atoms. It may be saturated or unsaturated. The aromatic polyester polyol may have an aromatic ring content of at least approximately 30% by weight, based on the total weight of the compound, 35% by weight, or even approximately 40% by weight. Here, as elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or undisclosed ranges. Polyester polyols having an acid component conveniently comprising at least approximately 30% by weight of italic acid residues, or residues of isomers thereof, are particularly useful.

[0047] The aromatic polyester polyol may have a hydroxyl number greater than approximately 50 mg KOH / g, greater than approximately 100 mg KOH / g, greater than approximately 150 mg KOH / g, greater than approximately 200 mg KOH / g, and greater than approximately 250 mg KOH / g. In one embodiment, the aromatic polyester polyol has a hydroxyl number of approximately 100 mg KOH / g and 300 mg KOH / g. Here, as elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or undisclosed ranges.

[0048] In one embodiment, the aromatic polyester polyol has a functionality greater than approximately 1, or greater than approximately 2. In one embodiment, the aromatic polyester polyol has a functionality of approximately 1 to 4, or approximately 1 to 2. Here, as elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or undisclosed ranges.

[0049] The foam composition also includes an isocyanate composition. The isocyanate may include at least one isocyanate and may include more than one isocyanate. The isocyanate may be selected from an aromatic isocyanate, an aliphatic isocyanate, or any combination thereof. The isocyanate composition may include an aromatic isocyanate such as a polymeric diphenylmethane diisocyanate (MDI). If the isocyanate composition includes an aromatic isocyanate, the aromatic isocyanate may correspond to the formula R1(NCO)z, where R1 is a polyvalent organic radical that is aromatic, and z is an integer corresponding to the valency of R1. Generally, z is at least 2.

[0050] The composition of isocyanate may include, but is not limited to, 1,4-diisocyanatobenzene, 1,3-diisocyanato-o-xylene, 1,3-diisocyanato-p-xylene, 1,3-diisocyanato-m-xylene, 2,4-diisocyanato-1-chlorobenzene, 2,4-diisocyanato-1-nitrobenzene, 2,5-diisocyanato-1-nitrobenzene, m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, 1,5-naphthalene diisocyanate, 1-methoxy-2,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate, and 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, triisocyanates such as 4,4'-,4-triphenylmethane triisocyanate, polymethyl polyphenylene polyisocyanate, and 2,4,6-toluene triisocyanate, tetraisocyanates such as 4,4'-dimethyl-2,2'-5,5'-diphenylmethane tetraisocyanate, toluene diisocyanate,2,2'-Diphenylmethane diisocyanate, 2,4'-Diphenylmethane diisocyanate, 4,4'-Diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate, corresponding isomeric mixtures thereof, and any combination thereof.

[0051] The foam composition also includes one or more catalysts. The catalyst is not particularly restricted and may be chosen from any suitable catalyst material to catalyze the reaction between a hydroxyl group of either water, a polyol, or any terminated hydroxyl compound and an isocyanate to form an expanded thermoset polyurethane-based polymer. Examples of suitable catalysts are selected from, but are not limited to, a gelation catalyst, a swelling catalyst, and / or a trimerization catalyst. Specifically,A gelation catalyst can catalyze the reaction of a hydroxyl group to an isocyanate to generate a urethane bond. A swelling catalyst can promote the reaction of water to an isocyanate to generate a urea bond. A trimerization catalyst can promote the reaction of three isocyanate groups to form an isocyanurate bond. The catalyst may include one or more catalysts and usually includes a combination of catalysts. The catalyst may or may not be consumed in the exothermic reaction depending on whether it contains a reactive isocyanate group. The catalyst may include any suitable catalyst or mixtures of catalysts known in the field. Examples of suitable catalysts include, but are not limited to, amine catalysts in appropriate diluents, e.g., dipropylene glycol; and metal catalysts, e.g., tin, bismuth, lead, etc. If included,the catalyst can be included in different applications. En una modalidad, el catalizador se selecciona del grupo de Ν,Ν-dimetilciclohexilamina (DMCHA), Ν,Ν,Ν',Ν',Ν' 'pentametildietilentriamine (PMDETA), b¡s-(2-d¡met¡lam¡noet¡l) éter, amidinas tales como 2,3-dimetil-3,4,5,6tetrahidropirimidina, otras aminas terciarias tales como trietilamina, tributilamina, dimetilbencilamina, N-metilmorfolina, Netilmorfolina, N-ciclohexilmorfolina, Ν,Ν,Ν ' ,N'-tetrametiletilenediamine, Ν,Ν,Ν ' ,N '-tetrametilbutandiamine, Ν,Ν,Ν ' ,N 'tetramethylhexano-1,6-diam¡na, mono ob¡s(d¡met¡laminoprop¡l)urea dimethylpiperacin, 1,2-dimethylimidazol, 1azabicyclo[3.3.0]octane, 1,4-diazabic¡clo[2.2.2]octane, alkanolamine compounds such as triethanolamine, triisopropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, dimethylethanolamine, tr¡s(d¡alqu¡lam¡noalqu¡l)-shexahidrotriacinas, including tris(N, Nd¡met¡lam¡noprop¡l)-s-hexah¡drotr¡ac¡na,tetraalkylammonium hydroxides including tetramethylammonium hydroxide, quaternary ammonium carboxylate salts, tetramethylammonium acrylate, tetraethylammonium acrylate, tetrapropylammonium acrylate, tetrabutylammonium acrylate, (2-hydroxypropyltrimethylammonium formate, (2-hydroxypropyl)trimethylammonium 2-ethylhexanoate, tetramethylammonium pivalate, tetraethylammonium pivalate, tetrapropylammonium pivalate, tetrabutylammonium pivalate, tetramethylammonium triethylacetate, tetraethylammonium triethylacetate, tetrapropylammonium triethylacetate, tetrabutylammonium triethylacetate, tetramethylammonium neoheptanoate, tetraethylammonium neoheptanoate, tetrapropylammonium neoheptanoate, tetrabutylammonium neoheptanoate, tetraethylammonium neooctanoate tetramethylammonium, tetraethylammonium neooctanoate, tetrapropylammonium neooctanoate, tetrabutylammonium neooctanoate, tetramethylammonium neodecanoate, tetraethylammonium neodecanoate, tetrapropylammonium neodecanoate,Tetrabutylammonium neodecanoate, alkali metal hydroxides including sodium hydroxide and potassium hydroxide, alkali metal alkoxides including sodium methoxide and potassium isopropoxide, alkali metal salts of long-chain fatty acids having 5 to 20 carbon atoms and / or side hydroxyl groups, tin, iron, lead, bismuth, mercury, titanium, hafnium, zirconium, iron(II) chloride, zinc chloride, lead octoate, stabilized stannous octoate, tin(II) salts of organic carboxylic acids such as tin(II) acetate, tin(II) octoate, tin(II) ethylhexanoate and tin(II) laurate, and dialkyltin(IV), salts of organic carboxylic acids such as dibutyltin dilaurate, dibutyltin diacetate, dibutyltin maleate and dioctyltin diacetate, potassium salts including potassium formate, potassium acetate, potassium propionate, potassium butanoate, potassium pentanoate, potassium hexanoate,Potassium heptanoate, potassium octoate, potassium 2-ethylhexanoate, potassium decanoate, potassium butyrate, potassium isobutyrate, potassium nonanoate, potassium stearate, 2-hydroxypropyltrimethylammonium octoate solution, sodium salts such as sodium octoate, sodium acetate, sodium caprioate, lithium salts such as lithium stearate, lithium octoate, and the like, or any combination thereof. In different embodiments, the catalyst may be included in amounts from 0.5 to 8 percent by weight of the total foam composition. Here, as elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or undisclosed ranges.

[0052] Foam compositions include a surfactant. The surfactant can be any surfactant suitable for use in the production of rigid foams (e.g., including those that can contribute to controlling or regulating cell size). Examples of such surfactants are the sodium salt of a castor oil sulfonate, a sodium salt of a fatty acid, a fatty acid salt with an amine, an alkali metal or ammonium salt of a sulfonic acid, a polyether siloxane copolymer, and a mixture of two or more of the same. In one aspect, the composition includes a silicone surfactant, and particularly a silicone-polyether surfactant. Other types of surfactants may be employed, e.g., a non-silicone surfactant, or a combination of both. In one embodiment, the surfactant may include nonionic surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants, and combinations thereof.In various embodiments, the surfactant may include, but is not limited to, polyoxyalkylene polyol surfactants, alkylphenol ethoxylate surfactants, and combinations thereof. In one embodiment, it includes salts of sulfonic acids, e.g., alkali metal and / or ammonium salts of oleic acid, stearic acid, dodecylbenzenedisulfonic acid or dinaphthylmethanedisulfonic acid, and ricinoleic acid, and other organopolysiloxanes, oxyethylated alkylphenols, oxyethylated fatty alcohols, paraffin oils, castor oil, castor oil esters, and ricinoleic acid esters, and cell regulators, such as fatty alcohols, and combinations thereof.

[0053] In one embodiment, the surfactant is selected from the group of silicone surfactants. Generally, silicone surfactants can control cell size, closed-cell content, flow, and limit void formation in the rigid foam produced from the reaction of the resin composition and the isocyanate composition. Examples of suitable surfactants include silicone-polyether surfactants, including those of the formula: M1D1xD2yM2(I) where M1 and M2 independently represent (CHsjsSiOi^, or (CH3)2R1S¡Oi / 2 D1 represents (CHs^SiC^, D2 represents (CH3)R1S¡02 / 2, x+y is generally from 10 to 150; and is generally at least 2; the ratio x / y is commonly from 2 to 15; and R1 is a polyether or mixture of independently selected and averaged, the formula of which is: —CnH2nO(C2H4O)t(C3H6O)zR2y having an average molecular weight number of 150 to 5000, wherein n is 2 to 4, t is a number such that the oxyethylene residue constitutes 40 to 100% by weight of the alkylene oxide residues of the polyoxyalkylene polyether, z is a number such that the propylene oxide residue constitutes 60 to 0% by weight of the alkylene oxide residues of the polyoxyalkylene polyether, and R2 represents a hydrogen or alkyl group having 1 to 4 carbon atoms or —C(O)CH3.

[0054] Silicone copolymer surfactants can be prepared by many synthetic approaches, including stepwise addition of polyethers. Furthermore, polyoxyalkylene polyether components are well known in the field and / or can be produced by any conventional process. For example, finished hydroxyalkylene polyethers, which are convenient raw materials in terpolymer preparation, can be prepared by reacting a suitable alcohol with ethylene oxide and propylene oxide (1,2-propylene oxide) to produce polyoxyalkylene polyethers of the desired molecular weights. Suitable alcohols are hydroxyalkenyl compounds, e.g., vinyl alcohol, allyl alcohol, methyl alcohol, and the like.In general, the alcohol initiator is preferably placed in an autoclave or other high-pressure vessel along with catalytic amounts of a suitable catalyst, such as sodium hydroxide, potassium hydroxide, other alkali metal hydroxides, or sodium or other alkali metals. Further details of the preparation are set forth, for example, in U.S. Patent No. 3,980,688, the full contents of which are incorporated herein by reference.

[0055] The alcohol-oxide reaction described above produces a monohydroxide-blocked-end polyoxyalkylene polyether in which the other blocking-end group is an unsaturated olefinic group consisting of any one of an allyl, metalyl, or vinyloxy group. These polyethers can be converted to isocyanate-nonreactive polyoxyalkylene polyethers by forming caps on the hydroxy-terminal group of such monohydroxide-blocked-end poly(oxyethyleneoxypropylene) copolymers by any conventional means.

[0056] The foam composition may comprise two or more different types of silicone surfactants.

[0057] Examples without limitation of conventional silicone surfactants suitable for foam composition include those available under the trade name Niax® from Momentive Performance Materials Inc. Suitable surfactants include, but are not limited to, Niax® L-6900, L-5111, L-6972, L-6633, L-6635, L-6190, L-6100, etc., or combinations of two or more of the same. occncn / ι ?n7 / □ / yl

[0058] The surfactant may be present in any appropriate amount. In different embodiments, the surfactant is present in amounts from 0.5 to 5, from 1 to 3, or approximately 2% by weight of the foam composition. Here and elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or unspecified ranges.

[0059] The foam composition may also include a non-silicone surfactant. The non-silicone surfactant may be used with or without silicone surfactants. Any surfactant known in the art may be used in the present invention. As such, the surfactant may include nonionic surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants, and combinations thereof. In different embodiments, the surfactant may include, but is not limited to, polyoxyalkylene polyol surfactants, alkylphenol ethoxylate surfactants, and combinations thereof. If the surfactant is included in the resin composition, the surfactant may be present in any appropriate amount.

[0060] The foam composition includes an additive composition comprising a siloxane-rich compound of defined molecular weight. This additive may also be referred to herein as a siloxane-rich composition. The siloxane-rich composition may comprise a compound of the formula: M3aD3bD4cTdQe(II) where M3 is a trialkyl end cap unit R3R4R5SIOi / 2-; D3 is a dialkyl unit Oi / 2R6R7SIOi / 2-; D4 is an alkyl unit - Oi / 2R8R9SIOi / 2—; T is -0^81(0^ -)2 R10; and Q is Si(Oi / 2-)4; R3, R4, R6, R7, R8, and R10 are independently fluorine, phenyl, or C1 to C10 alkyl groups, eventually partially or completely substituted fluorine or phenyl; R5 is fluorine; phenyl; or C1 to C10 alkyl groups optionally partially or completely substituted with fluorine or phenyl; or -R11-Om-(CH2-CH2-O)q(CH2-CH(CH3)-O)p-R12; R9es -R11-Om-(CH2-CH2-O)q(CH2-CH(CH3)-O)p-R12; R11 is hydrocarbon group C1 to C10; R12 is hydrogen, phenyl, fluorine, or a C1-C8 hydrocarbon group, in which fluorine or phenyl are partially or completely substituted and optionally interrupted by urethane, urea, or carbonyl groups. a and b are independently from 0 to 30; c, d, and y are independently from 0 to 5; m is 0 or 1; q and p are independently from 0 to 10; provided that b + c is at least 1; provided that the siloxane-rich component has a silicon content of at least 25% by weight.

[0061] In various forms, the siloxane-rich compound has an average molecular weight number of approximately 200 to 3000 daltons; approximately 300 to 2500 daltons; approximately 400 to 2000 daltons; and approximately 450 to 2000 daltons. These numerical values ​​can be combined to form new and unspecified ranges. The average molecular weight number can be determined by nuclear magnetic resonance (NMR). Nuclear Magnetic Resonance) of silicon (29S¡ NMR).

[0062] In some forms, the siloxane-rich composition is based on a molecular weight distribution containing 2.5 wt% or less of siloxane-based species having a molecular weight below 400. In one form, a composition is provided in accordance with any of the above forms, wherein the siloxane-rich composition is based on a molecular weight distribution containing 2.5 wt% or less of siloxane-based species having a molecular weight below 400; below 350; below 300; or below 250. The molecular weight can be assessed and quantified using gas chromatography recalculated to wt% using calibration factors.

[0063] In certain embodiments, the siloxane-rich composition includes standard low-molecular-weight cyclic siloxanes having 3 to 6 siloxane units in amounts of approximately 5% or less; 4% or less; 2.5% or less; 1% or less; or 0.5% or less. In certain embodiments, the siloxane-rich composition has these residual cyclic siloxane species at a very low level, each below 0.1%. Typical low-molecular-weight cyclic siloxanes are hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6).

[0064] The silicon content of the siloxane-rich composition is at least 25% by weight or more; at least 28% by weight or more; at least 30% by weight or more, up to approximately 32% by weight.

[0065] In one embodiment, the siloxane-rich composition preferably has on average 2 or fewer reactive groups per molecule that can react with isocyanate; 1 or fewer reactive groups per molecule that can react with isocyanate; or no reactive groups that can react with isocyanate.

[0066] In one embodiment, the siloxane-rich composition is a polydimethylsiloxane having an average molecular weight number of approximately 200 to 3000 daltons; approximately 300 to 2500 daltons; approximately 450 to 2000 daltons; with less than 2.5% by weight of species having a molecular weight below 400.

[0067] The composition comprising the siloxane-rich compounds may comprise a combination of different siloxane-rich compounds as described in Formula (II). The siloxane-rich compounds are provided in the foam formulation such that the siloxane-rich composition on a weight basis relative to the total weight of the formulation excluding the blowing agent is approximately 0.02% to 5%; approximately 0.03% to 4%; or even approximately 0.05% to 3%.

[0068] The siloxane-rich composition can be provided as a separate additive or added as part of a composition comprising a surfactant, the siloxane-rich composition, and finally a diluent or other relevant component for incorporation as an ingredient in the foam formulation. Examples of suitable diluents include, for example, dipropylene glycol, hexylene glycol, or polymers obtained from alkoxylated initiators of different functionalities from 1 to 10, etc.

[0069] The foam composition may also include one or more blowing agents, including, but not limited to, physical blowing agents, chemical blowing agents, or any combination thereof. In one embodiment, the blowing agent may include both a physical and a chemical blowing agent, and the blowing agent may be included in the foam composition. The physical blowing agent generally does not react chemically with the resin composition and / or an isocyanate to produce a foaming gas. The physical blowing agent may be a gas or a liquid. A liquid physical blowing agent may evaporate into a gas when heated and may revert to a liquid when cooled. The physical blowing agent may reduce the thermal conductivity of rigid polyurethane foam.The swelling agent may include, but is not limited to, methylene chloride, acetone, and liquid carbon dioxide, aliphatic and / or cycloaliphatic hydrocarbons, halogenated hydrocarbons and alkanes, acetals, water, alcohols, formic acid, and any combination thereof. In some embodiments, the composition comprises a chemical swelling agent selected from water, formic acid, or a combination thereof.

[0070] In various embodiments, the swelling agent may be selected from hydrocarbons, hydrofluorocarbons, hydrochlorofluoroolefins (HCFOs) and hydrofluoroolefins (HFOs), non-halogenated volatile C2-C7 hydrocarbons such as alkanes, including n-pentane, isopentane and cyclopentane, alkenes, cycloalkanes having up to 6 carbon atoms, dialkyl ethers, cycloalkylene ethers and ketones, and hydrofluorocarbons, C1-C4 hydrofluorocarbons, non-halogenated volatile hydrocarbons such as linear or branched alkanes such as butane, isobutane, 2,3-dimethylbutane, n- and isohexanes, n- and isoheptanes, n- and isooctanes, n- and isononanes, n- and isodecane, n- and isoundecanes, and n- and isododecane, alkenes such as 1-pentene, 2-methylbutene, 3-methylbutene, and 1-hexene, cycloalkanes such as cyclobutane and cyclohexane, linear and / or cyclic ethers such as dimethyl ether, diethyl ether, methyl ethyl ether, vinyl methyl ether, vinyl ethyl ether, divinyl ether,dimethoxymethane (methylal), tetrahydrofuran and furan, ketones such as acetone, methyl ethyl ketone and cyclopentanone, isomers thereof, esters of carboxylic acids such as methyl methanoate (methyl formate), hydrofluorocarbons such as difluoromethane (HFC-32), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1-difluoroethane (HFC-152a), 1,2-difluoroethane (HFC-142), trifluoromethane, heptafluoropropane (R-227a), hexafluoropropane (R-136), 1,1,1-trifluoroethane, 1,1,2-trifluoroethane, fluoroethane (R-161), 1,1,1,2,2-pentafluoropropane, pentafluoropropylene (R-2125a), 1,1,1,3-tetrafluoropropane, tetrafluoropropylene (R-2134a), difluoropropylene (R-2152b), 1,1,2,3,3-pentafluoropropane, 1,1,1,3,3-pentafluoro-n-butane, and 1,1,1,3,3-pentafluoropentane (245fa), isomers thereof, 1,1,1,2-tetrafluoroethane (HFC-134a), isomers thereof, and combinations thereof. In different embodiments, the swelling agent may also be defined as 1,1,1,3,3-pentafluoropentane (245fa) or a combination of HFCs 245fa, 365MFC, 227ea, and 134a. In an alternative embodiment, the swelling agent may be further defined as 365MFC, which may be mixed with 227ea. In an additional embodiment, the swelling agent may be further defined as a cis or trans isomer of 1-chloro-3,3,3-trifluoropropene or 1,1,1-4,4,4-hexafluoro-2-butene, or a combination thereof with each other or with any other swelling agent mentioned above.

[0071] In different embodiments, the blowing agent may be present in amounts of 0.1 to 30, or 1 to 25, or 2 to 20, or 3 to 18, or 5 to 15, percent by weight of the foam composition. Here, as elsewhere in the specification and in the claims, the numerical values ​​may be combined to form new or undisclosed ranges. Generally, the amount of blowing agent and / or water may be selected based on a desired density of the rigid foam and the solubility of the blowing agent in the resin composition, when relevant.

[0072] The foam composition may also include a crosslinking agent and / or a chain extender. The crosslinking agent may include, but is not limited to, an additional polyol, amines, and combinations thereof. If the crosslinking agent is included in the foam composition, the crosslinking agent may be present in any appropriate amount. Chain extenders contemplated for use in the present technology include, but are not limited to, hydrazine, primary and secondary diamines, alcohols, amino acids, hydroxy acids, glycols, and combinations thereof.Specific chain extenders being considered for use include, but are not limited to, mono- and di-ethylene glycols, mono- and di-propylene glycols, 1,4-butanediol, 1,3-butanediol, propylene glycol, dipropylene glycol, diethylene glycol, methyl propylene diol, mono-, di- and tri-ethanolamines, N-N'-bis-(2-hydroxypropylaniline), trimethylolpropane, glycerin, hydroquinone bis(2-hydroxyethyl) ether, 4,4'-methylene-bis(2-chloroaniline), diethyltoluenediamine, 3,5-dimethylthiotoluenediamine, hydrazine, isophorone diamine, adipic acid, silanes, and any combination thereof.

[0073] The foam composition may also include one or more additives. Suitable additives include, but are not limited to, non-reactive flame retardants (e.g., various phosphates, various phosphonates, triethyl phosphate, trichloropropyl phosphate, triphenyl phosphate, or diethyl ethyl phosphonate, tris(2-chloroethyl)phosphate, tris-ethyl phosphate, tris(2-chloropropyl)phosphate, tris(1,3-dichloropropyl)phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, alumina trihydrate, polyvinyl chloride, and any combination thereof), OH-free / non-reactive flame retardants, chain terminators, modified or unmodified phenolic resins, inert thinners, amines, anti-swelling agents, air-releasing agents, wetting agents, surface modifiers, waxes, inert inorganic fillers, molecular sieves, fillers reactive inorganics, crushed glass, other types of glass such as glass matting,Processing additives, surface-active agents, adhesion promoters, antioxidants, inks, pigments, ultraviolet light stabilizers, thixotropic agents, anti-aging agents, antistatic additives, lubricants, coupling agents, solvents, rheology promoters, cell openers, release additives, and combinations thereof. One or more of these additives may be present in the foam composition in any quantity.

[0074] In addition to the foam composition, this technology also provides a method for forming the foam, and a method for forming the foam on a surface.

[0075] The method for forming rigid foam generally includes the step of combining the polyols, the isocyanate composition, the surfactant, the siloxane-rich composition, and all other additives. The isocyanate index of the foam is generally not limited. Most generally, the polyol and isocyanate composition are combined in such a way that the isocyanate index is generally above 120 and can reach values ​​of 500 or even 600 depending on the type of foam being made, whether PUR or PIR. Those experienced in the matter will appreciate that the foam can be a polyurethane (PUR, with an index generally below 200) or a polyisocyanurate (PIR, with an index generally well above 200 and typically above 250). It will be noted, however, that there is no absolute value for the index to define a PUR foam or a PIR foam.

[0076] The method for forming the rigid foam on the surface may include the steps of combining the components to form a foam mixture. Generally, the combining step may occur in a mixing apparatus such as a static mixer, a mechanical or incidence mixing chamber, or a mixing pump. In one embodiment, the mixing step occurs in a static mixing tube. Alternatively, the foam composition and the isocyanate composition may be combined in a spray nozzle.

[0077] The method for forming rigid or semi-rigid foam may include air nucleation to one or more of the formulation components when processed in an industrial mixing equipment.

[0078] The components can be combined while on a surface or separated from the surface. In one embodiment, the components can be combined in the head of a spray gun or in the air above the surface to which the composition is being applied. The components can be combined and applied to the surface by any method known in the field, including spraying, dipping, pouring, coating, painting, etc.

[0079] The present technology provides a semi-rigid or rigid polyurethane foam (rigid or semi-rigid foam). The rigid foam may be open-cell or closed-cell and may include a highly cross-linked polymer structure that allows the foam to have good heat stability, high compressive strength at low density, low thermal conductivity, and good barrier properties. Generally, the rigid foam of this technology may have a glass transition temperature higher than ambient temperature (approximately 23°C + / - 2°C (73.4°F +1- 3.6°F)) and is generally rigid at ambient temperature. Generally, the foams are rigid below their glass transition temperatures, especially in the glassy regions of their storage modules.The polyurethane foam material can have a density of approximately 10 to 900 kg / m³, approximately 15 to 800 kg / m³, approximately 20 to 500 kg / m³, or approximately 30 to 400 kg / m³. In one embodiment, the rigid foam can have a density of approximately 10 to 60 kg / m³. Here, as elsewhere in the specification and in the claims, the numerical values ​​can be combined to form new or undisclosed ranges.

[0080] The foam mixture can be applied to any suitable surface, e.g., brick, concrete, masonry, gypsum board, drywall, plaster, metal, stone, wood, plastic, a polymer composite, or any combination thereof. Additionally, the surface can be a mold surface, and the rigid foam can therefore be formed in the mold.

[0081] The resulting rigid or semi-rigid foam can be used in the form of a sheet, a mold, a panel, or a filled cavity. The filled cavity, for example, can be a tube, an insulated wall, or an insulated hull structure. The rigid foam can be spray foam, foamed foam, or a continuously manufactured laminated product or a discontinuously manufactured laminated product, including, but not limited to, a sheet or laminate product formed with other materials such as particleboard, gypsum board, plastics, paper, metal, or a combination thereof.

[0082] Rigid foams prepared according to the embodiments of the present technology may exhibit improved processability. The present foam may exhibit reduced defects, including, but not limited to, decreased shrinkage and warping. These characteristics may be useful in the manufacture of sandwich panels. Sandwich panels may comprise at least one relatively flat layer (i.e., a layer having two generally large dimensions and one generally small dimension) of the rigid foam, oriented toward each of its larger dimensioned sides, with at least one layer, on such side, of flexible or rigid material, such as a sheet or a thicker layer of a metal or other material that provides structure. One such layer may, in certain embodiments, serve as the substrate during foam formation.

[0083] Additionally, the foam mixture produced by the method described above from the components identified above may have improved thermal insulation, e.g., lower thermal conductivity. In particular, the present compositions employing a siloxane composition of the described structure and with specific molecular weights may reduce the thermal conductivity of the foam relative to a similar foam composition that lacks the described siloxane composition.

[0084] Rigid foams comprising the siloxane-rich compositions described above may be further understood by reference to the following examples. EXAMPLES

[0085] Foam preparation and test methodology

[0086] The foams were generally prepared by first making a resin mixture comprising the different polyols, flame retardants, catalysts and water in a 1 liter plastic cup.

[0087] An appropriate weight was used to obtain sufficient free lift height, maintaining the formulation component ratios as indicated in Tables 1a-1 and 3. The conventional surfactant and the siloxane-rich composition were subsequently added either separately or as a mixture if the surfactant was at a low level that would prevent accurate weighing. In both cases, they were carefully mixed with a spatula until the premixed mixture was homogeneous. The physical swelling agent, a pentane isomer or a mixture thereof, was added to this resin mixture to the target weight, then carefully mixed with a spatula until the premixed mixture was homogeneous. A small amount of extra pentane was added to achieve the required weight to correct for minor losses due to evaporation during mixing. This was repeated until the required weight was reached and stabilized.The resulting mixture was further mixed using a mechanical mixer at 4000 rpm for 10 seconds. The required amount of isocyanate was pre-weighed in a separate cup and quickly added to the cup containing the polyol-pentane premix to provide a reactive mixture. The reactive mixture was further mixed at 4000 rpm for 5 seconds using a high-energy mechanical mixer equipped with a 6 cm circular impeller and immediately poured into an open square paper cup mold with a 23 x 23 cm cross-section and 20 cm height, enclosed on the sides with a square wooden frame. The pouring was done in the center of the square section. The foam expanded freely in the vertical direction. The creaming time and gel time were measured with the remaining reactive material in the cup.A free-rising rigid foam was obtained and allowed to cool and cure for the next 24 hours at room temperature inside the open paper mold.

[0088] A piece of the foam was then cut from the center of the block after 24 hours, measuring 20x20x4 cm, and its thermal conductivity was evaluated. This piece was used to measure the foam core density and thermal conductivity (also called lambda value) between either 0°C and 20°C (average temperature of 10°C) or 10°C and 36°C (average temperature of 23°C) using a FOX Lasercomp 200 heat flowmeter. The recorded value was termed the initial thermal conductivity. occncn / i ?n7 / □ / yl

[0089] Raw material used in the compositions

[0090] Stepanpol PS 2412 is an aromatic polyester polyol obtained from Stepan Voranol. RN411 is a polyether polyol obtained from Dow Chemicals. Daltocel R585 is a polyether polyol obtained from Huntsman Co. The liquid flame retardant TCPP is tris(1-chloro-2-propyl) phosphate. Niax A-1, C-5, C-8, and potassium octoate are commercial catalysts from the Momentive Urethane Additives portfolio. Desmodur 44V70L and Suprasec 5025 are polymeric MDI grades obtained from Covestro and Huntsman Co., respectively.

[0091] Tables 1a-1c show a general formulation of PIR foams, e.g., foams made with a formulation where the isocyanate index is generally above 200. For the listed experiments, an index of 300 was selected, a normal value used for PIR foams, for example, for constructing either flexible or metal-surface panels. The blowing agent used is n-pentane, and the lambda value was measured at a mean temperature of 10°C, between plate temperatures of 0°C and 20°C. Table 1a Foam 1a 1b 1c 2 3 4 5 Formulation Aromatic polyester polyol, Stepanpol PS 2412 Liquid flame retardant TCPP 15.0 15.0 15.0 15.0 15.0 15.0 15.0 Water 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Niax C-5 Catalyst 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Potassium Octoate Niax 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Silicone stabilizer for conventional rigid foam 1.6 1.6 1.6 2.8 5 1.6 1.6 n-pentane 20 20 20 20 20 20 20 Polymeric MDI, Desmodur 44V70L Table 1a (continued) Foam 1a 1b 1c 2 3 4 5 Formulation Added Siloxane Composition 1 0.2 1.2 Added Siloxane Composition 2 Added Siloxane Composition 3 Added Siloxane Composition 4 Added Siloxane Composition 5 Added Siloxane Composition 6 Added Siloxane Composition 7 Added Siloxane Composition 8 Weight of Siloxane Compound in Added Siloxane-Based Composition (%) - - - - - 100 100 Siloxane Compound, Calculated Parameters Silicon % * - - - - - 37.05 37.05 Average Molecular Weight * - - - - - 630 630 Average Number of Reactive Groups / Molecules * - - - - - 0 0 Added Siloxane Compound on Total Formulation ** (%) 0 0 0 0 0 0.06 0.35 Isocyanate index 300 300 300 300 300 300 300 Reactivity - Gel time (s) 60 65 57 58 63 62 60 Foam density (kg / m3) 33 32 33 31 32 32 30 Cell size / structure controlled controlled controlled controlled controlled controlled controlled controlled Thermal conductivity after 24 hours (Lambda 0 -20°C, in mW / K.m) 24.1 24.4 24.21 24.36 23.81 23.42 23.03. occncn / 17n7 / □ / yl Tabla 1b Foam 6 7 8 9 10 11 12 13 Formulation Aromatic polyester polyol, Stepanpol PS 2412 100 100 100 100 100 100 100 100 Liquid flame retardant TCPP 15.0 15.0 15.0 15.0 15.0 15.0 15.0 15.0 Water 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Niax C-5 Catalyst 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 Niax Potassium Octoate 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Silicone stabilizer for conventional rigid foam 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 n-pentane 20 20 20 20 20 20 20 20 Polymeric MDI, Desmodur 44V70L 218 218 218 218 218 218 218 218 Added siloxane composition 1 5 Added siloxane composition 2 0.2 1.2 5 Added siloxane composition 3 1.2 Added siloxane composition 4 1.2 5 Added siloxane composition 5 0.2 Added siloxane composition 6 Added siloxane composition 7 Added siloxane composition 8 Weight siloxane compound in composition based on siloxane added (%) 100 100 100 100 100 100 100 100 Siloxane compound, calculated parameters Silicon % * 37.05 37.2 37.2 37.2 37.6 37.8 37.8 34.65 Average molecular weight * 630 697 697 697 898 3310 3310 162.4 Average number of reactive group / molecule * 0 0 0 0 0 0 0 0. occncn / Lznz / q / YiAi Table 1b (continued) Foam 6 7 8 9 10 11 12 13 Formulation Siloxane compound added on total formulation ** (%) 1.46 0.06 0.35 1.46 0.35 0.35 1.48 0.06 Isocyanate index 300 300 300 300 300 300 300 300 Reactivity - Gel time (s) 60 60 57 60 58 63 68 62 Foam density (kg / m3) 31 32 31 32 32 31 32 33 Cell size / structure controlled controlled controlled controlled controlled controlled controlled controlled controlled controlled Thermal conductivity after 24 hours (Lambda 0 -20°C, in mW / Km) 22.84 23.49 22.81 22.9 23.24 24.49 24.66 24.01 occncn / 17n7 / □ / yl Table 1c Foam 14 15 16 17 Formulation Aromatic polyester polyol, Stepanpol PS 2412 100 100 100 100 Liquid flame retardant TCPP 15.0 15.0 15.0 15.0 Water 0.8 0.8 0.8 0.8 Niax C-5 catalyst 0.25 0.25 0.25 0.25 Niax potassium octoate 2.5 2.5 2.5 2.5 Silicone stabilizer for conventional rigid foam 1.6 1.6 1.6 1.6 n-pentane 20 20 20 20 Polymeric MDI, Desmodur 44V70L 218 218 218 218 Added siloxane composition 1 Added siloxane composition 2 Composition of Added siloxane 3 Added siloxane composition 4 Added siloxane composition 5 5 Added siloxane composition 6 0.2 Added siloxane composition 7 1.2 Added siloxane composition 8 1.2 Weight siloxane compound in added composition (%) 100 100 87.3 87 Table 1c (continued) Foam 14 15 16 17 Formulation Siloxane Compound, Calculated Parameters Silicon % * 34.65 37.2 19.5** 19.1** Average Molecular Weight * 162.4 830 720 ** 740 ** Average Number of Reactive Groups / Molecules * 0 0 1 0 Added Siloxane Compound on Total Formulation ** (%) 1.46 0.06 0.31 0.31 Isocyanate Index 300 300 300 300 Reactivity - Gel Time (s) 65 65 62 60 Foam Density (kg / m3) 30 32 33 31 Controlled Cell Size / Structure Controlled Controlled Controlled Thermal Conductivity after 24 hours (Lambda 0 -20°C, in mW / Km) 24.2 23.54 24.26 23.97 occncn / i ?n7 / □ / yl Notes for Tables 1 a-1c * Excess polyether reactant is excluded in case of siloxane modification * * Weight of physical swelling agent is excluded For both tables 1a-cy 3, the following silicone-based composition was used: Silicone stabilizer for conventional rigid foam: A copolymer obtained from the reaction of a linear silicone hybrid of 65D units and 7.5D' units in an EO / PO polyether terminated with 30% polyether excess hydroxyl. The polyether contains approximately 12.8 ethylene oxide (EO) units and 3.2 propylene oxide (PO) units. The siloxane copolymer has a silicone content of approximately 19% and an average molecular weight number of approximately 11,000 daltons. • Table 2 describes siloxane-based compositions 1 to 4. • Siloxane 5 composition: Hexamethyldisiloxane, or MM • Siloxane 6 composition: An unmodified polydimethylsiloxane, type T, with average structure M3D7T • Siloxane 7 composition: Modified siloxane obtained by reacting MD'M with polyethylene oxide terminated with allyl hydroxy, EO 6.6 units • Siloxane 8 composition: Modified siloxane obtained by reacting MD'M with polyethylene oxide terminated with allyl methoxy, EO 6.6 units Table 2 Average molecular weight number* (Dalton) Low molecular weight linear species present at a cumulative weight of less than 2.5% of the total composition (Dalton) High molecular weight linear species present at a very low cumulative level of the total composition**** (Dalton) Residual cyclic siloxanes D4, D5 and D6 ***** (% by weight) Composition of siloxane 1 630 400 and below** 1050 and above Below 0.5 Composition of siloxane 2 697 400 and below** 1180 and above Below 0.5 Composition of siloxane 3 898 500 and below** 2870 and above Below 0.5 Composition of siloxane 4 3310 550 and below*** 22250 and above Below 0.5 occncn / 17Π7 / □ / yl Notes for Table 2 * : Determined by NMR as the average number of D units per two M endings * *: Determined by gas chromatography, recalculated as wt.% using calibration factors * **: Determined by Gel Permeation Chromatography (GPC), as molecular weights contributing less than 0.5% of the total integral on the low molecular weight side - polydimethylsiloxane standards were used for calibration * ***: Determined by Gel Permeation Chromatography (GPC), as molecular weights contributing less than 1% of the total integral on the high molecular weight side - polydimethylsiloxane standards were used for calibration * ****: D4, D5, and D6 are common cyclic residual species in siloxane compositions: octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6). respectively.The levels were obtained by liquid extraction from the compositions followed by gas chromatography of the extracted mixture. The results show that a conventional silicone surfactant incorporated at a standard level of 1.6 to 2.8 parts per 100 parts of the main polyol results in foam thermal conductivity values ​​(or lambda values) in the range of 24 to 24.5 mW / mK, foams 1a to 1c. Some standard dispersion was observed with the foam without added siloxane composition, but still within the range of 24 to 24.5 mW / mK. Increasing the level of conventional surfactant to very high values, such as 5 parts, can yield a marginally lower lambda value of 23.81 mW / mK, but this is a very small benefit considered not highly significant. It was found that by adding, in addition to the conventional silicone surfactant, a siloxane-rich composition of selected molecular weight, at a level as low as 0.2 parts per 100 parts or more of the main polyol, significantly lower foam lambda values ​​can be obtained.This can be seen with siloxane compositions 1 through 3 or 6, which fall within the scope of the invention. Comparative examples using siloxane compositions 4, 5, 7, or 8, which have lower or higher molecular weights or lower silicon content and are outside the scope of the invention, did not provide such a benefit. All foams generated from these experiments are not significantly different in other basic foam characteristics such as reactivity (as quantified by Gel Time) and foam density.

[0092] Table 3 shows a common formulation for PUR foams, e.g., made with a formulation where the calculated isocyanate excess is significantly less than 200. For the experiment listed in Table 3, a molar isocyanate excess of 30% was used, indicating an isocyanate index of 130. The swelling agent used for this formulation is cyclopentane, and the lambda values ​​were measured at a mean temperature of 23°C, with plate temperatures between 0°C and 36°C. Table 3 occncn / i ?n7 / □ / yl Foam 2 Ex. 18 Ex. 19 Ex. 20 Ex. 21 Ex. 22 Daltolac R585 polyether polyol 50 50 50 50 50 50 Voracor N411 polyether polyol 50 50 50 50 50 50 TCPP liquid flame retardant 10.0 10.0 10.0 10.0 10.0 10.0 Water 2.0 2.0 2.0 2.0 2.0 2.0 Niax C-8 Catalyst 2.3 2.3 2.3 2.3 2.3 2.3 Niax A-1 Catalyst 0.7 0.7 0.7 0.7 0.7 0.7 Silicon stabilizer for conventional rigid foam 3.0 3.0 3.0 3.0 3.0 3.0 Cyclopentane 18.0 18.0 18.0 18.0 18.0 18.0 Total Side B 136.0 136.0 136.0 136.0 136.0 136.0 Low Viscosity Polymeric MDI 177.0 177.0 177.0 177.0 177.0 177.0 Added Siloxane Composition 2 1 Added Siloxane Composition 5 1 Added Siloxane Composition 6 1 Added Siloxane Composition 7 1 Added Siloxane Composition 8 1 Weight Siloxane Compound in Added Composition (%) - 100 100 100 87.3 87 Siloxane Compound, Calculated Parameters Silicon % * - 37.2 34.65 37.2 19.5** 19.1** Table 3 (continued) Foam 2 Ex. 18 Ex. 19 Ex. 20 Ex. 21 Ex. 22 Average molecular weight * - 697 162.4 830 720 ** 740** Average number of reactive group / molecule * - 0 0 0 1 0 Siloxane-rich compound on total formulation** (%) - 0.34 0.34 0.34 0.34 0.34 Isocyanate index 130 130 130 130 130 130 Reactivity - Gel time (s) 55 55 51 51 53 55 Foam density (kg / m3) 27 27 28 28 27 27 Cell size / structure controlled controlled 0 controlled 0 controlled 0 controlled 0 controlled 0 controlled 0 Thermal conductivity after 24 hours (Lambda 10 -36°C, in mW / Kxm) 24.74 24.23 24.72 24.34 24.56 24.79 occncn / 17n7 / □ / yl * Excess polyether reactant is excluded in case of siloxane modification ** Weight of physical swelling agent is excluded

[0093] These PUR formulations show an effect comparable to that obtained for the PIR formulation. With added siloxane compositions 2 and 6, which fall within the scope of the aspects and modes of the invention, a significant thermal conductivity benefit of 0.4 mW / mK and more is achieved against control foam 2. Comparative examples using added siloxane compositions 5, 7, or 8, which fall outside the scope of the invention, do not improve the lambda values ​​for siloxane compositions 5 and 8 or show a marginal benefit on the order of 0.2 mW / mK for siloxane composition 7. Again, the foams generated other basic characteristics such as reactivity as quantified by gel time and foam density that are not significantly different. Some aspects of the technology have been described above, and modifications and alterations to others may occur after reading and understanding this specification. The following claims are intended to include all modifications and alterations to the extent they fall within the scope of the claims or their equivalents.

Claims

1. A composition for use as an additive in a polyurethane foam formulation, the composition comprising a siloxane-rich compound of the formula M3aD3bD4cTdQe (II) where M3 is a trialkyl end-cap unit R3R4R5SiOi / 2—; D3 is a dialkyl unit -Oi / 2R6R7SiOi / 2—; D4 is an alkyl unit -O^R^SiOi / r-; T is -O^81(O^ ​​-)2 R10i; Q is Si(Oi / 2-)4; R3, R4, R6, R7, R8, and R10 are independently fluorine, phenyl, or C1 to C10 alkyl groups, with time fluorine or phenyl partially or fully substituted; R5 is fluorine; phenyl; or C1 to C10 alkyl groups optionally partially or completely substituted with fluorine or phenyl; or -R11-Om-(CH2-CH2-O)q(CH2-CH(CH3)-O)p-R12; R9 is -R11-Om-(CH2-CH2-O)q(CH2-CH(CH3)-O)p-R12; R11 is a C1 to C10 hydrocarbon group; R12 is hydrogen, phenyl, fluorine, or a C1-C8 hydrocarbon group, in embodiments where fluorine or phenyl are partially or completely substituted and optionally interrupted by urethane, urea, or carbonite groups.a and b are independently from 0 to 30; c, d, and e are independently from 0 to 5; m esOo 1; q and p are independently from 0 to 10; c on the condition that b + c is at least 1; a on the condition that the siloxane-rich component has a silicon content of at least 25% by weight.

2. The composition according to claim 1, wherein the siloxane-rich compound or mixture has an average molecular weight number between 200 and 3000 daltons.

3. The composition according to claim 1, wherein the siloxane-rich compound or mixture has an average molecular weight number between 300 and 2500 daltons.

4. The composition according to claim 1, wherein the siloxane-rich compound or mixture has an average molecular weight number between 450 and 2000 daltons.

5. The composition according to any of claims 1 to 4, wherein the siloxane-rich compound or mixture has a silicon content above 28% by weight.

6. The composition according to any of claims 1 to 4, wherein the siloxane-rich compound or mixture has a silicon content above 28% by weight up to 32% by weight.

7. The composition according to any of claims 1 to 6, wherein the siloxane-rich compound or mixture has an average of 2 or fewer reactive groups per molecule that can react with isocyanate.

8. The composition according to any of claims 1 to 7, wherein the siloxane-rich compound or mixture has on average less than 2 or no reactive groups that can react with isocyanate.

9. The composition according to any of claims 1 to 8, wherein the subscript a of the siloxane-rich compound is equal to at least 1.

10. The composition according to any of claims 1 to 9, wherein the siloxane-rich composition is based on a molecular weight distribution containing 2.5% by weight or less of siloxane-based species having a molecular weight below 400.

11. The composition according to any of claims 1 to 10, wherein the siloxane-rich composition contains approximately 5% by weight or less of cyclic siloxane species having 3 to 6 siloxane groups selected from hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6).

12. A process for producing a polyurethane foam by reacting the different components of a formulation comprising: a polyol; an isocyanate; a catalyst; a surfactant; a physical swelling agent; and a siloxane-rich composition according to any one of claims 1 to 11.

13. The process according to claim 12, comprising the siloxane-rich composition or mixture in an amount of at least 0.02% by weight of the total weight of the formulation components excluding physical swelling agents.

14. The process according to any of claims 12 to 13, comprising the siloxane-rich composition or mixture in an amount of at least 0.03% by weight of the total weight of the formulation components excluding physical swelling agents.

15. The process according to any of claims 12 to 13, comprising the siloxane-rich composition or mixture in an amount of at least 0.05% by weight of the total weight of the formulation components excluding physical swelling agents.

16. The process according to any of claims 12 to 15, comprising the siloxane-rich composition or mixture in an amount of 3% by weight or less of the total weight of the formulation components excluding physical swelling agents.

17. The process according to any of claims 12 to 16, comprising the siloxane-rich composition or mixture in an amount of approximately 0.05% by weight to 3% by weight of the total weight of the formulation components excluding physical swelling agents.

18. The process according to any of claims 12 to 17, wherein the siloxane-rich composition or mixture occncn / 17n7 / □ / yl is added to a premix formulated to be mixed with an isocyanate component to produce a polyurethane foam used as a thermal insulation material.

19. The process according to any of claims 12 to 18, wherein the siloxane-rich composition or mixture is added as a separate component in a foam dispensing unit to produce a polyurethane foam used as a thermal insulation material.

20. The process according to any of claims 12 to 19, wherein the siloxane-rich composition or mixture is added to an isocyanate component to be mixed with reactive isocyanate ingredients to produce a polyurethane foam used as a thermal insulation material.

21. The process according to any of claims 12 to 20, wherein the siloxane-rich composition or mixture is added to the polyurethane foam formulation in addition to a surfactant, which optionally contains siloxane, the portion of such surfactant containing siloxane, if present, having a silicon content of less than 25% and an average molecular weight number above 2000 daltons.

22. The process according to any of claims 12 to 21, wherein the process forms a rigid or semi-rigid polyurethane foam.

23. The process according to claim 22, wherein the rigid or semi-rigid polyurethane foam has a density between 10 and 100 kg / m3 and an isocyanate index between 100 and 500.

24. A polyurethane foam formed from the composition of any of claims 111.

25. The polyurethane foam according to claim 23, wherein the foam is a rigid or semi-rigid polyurethane foam having a density between 10 and 100 kg / m3 and an isocyanate index between 100 and 500.

26. The polyurethane foam according to claim 24, wherein the foam has an initial thermal conductivity of approximately 23 mW / m·K or less at an average temperature of 0°C to 30°C.

27. A thermal insulation material comprising polyurethane foam according to claim 25 or 26.

28. An article comprising polyurethane foam according to any of claims 24 to 26.