Silicone-acrylic binder for liquid-applied insulation coating compositions resistant to

Abstract

A silicone-acrylic adhesive is made from a combination of I) a first aqueous emulsion containing a soft acrylic polymer, II) a second aqueous emulsion containing a hard acrylic polymer, and III) an aqueous emulsion of a polyorganosiloxane elastomer. The silicone-acrylic binders can be used to prepare thermal insulation coating compositions that can be applied to metal (e.g., steel) substrates or primed substrates. A thermal barrier coating prepared by drying the thermal barrier coating composition provides corrosion resistance under thermal barrier to a metal or primed substrate.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 586,428, filed September 29, 2023, pursuant to 35 USC §119(e). U.S. Provisional Patent Application Serial No. 63 / 586,428 is hereby incorporated by reference. Technical Field

[0003] This invention relates to silicone-acrylic adhesives, heat-insulating coating compositions, and methods for preparing them. More specifically, the adhesive and heat-insulating coating compositions comprise a first (soft) acrylic polymer, a second (hard) acrylic polymer, and a silicone elastomer. The compositions can be applied to metal surfaces or primer-coated substrates and provide a heat-insulating coating with good corrosion protection under the insulation layer. Background Technology

[0004] Thermal insulation materials are used to prevent heat transfer from the interior of equipment (operating equipment or devices, such as storage tanks, pipelines, containers, furnaces, valves, boilers, etc.) to the external environment, thereby improving process reliability and providing personnel protection. Mechanical (or physical or intrinsic) insulation solutions (such as fiberglass, foam wrapping, metal sheathing, etc.) may be difficult to install on complex geometries and, if exposed to water, may absorb water like a sponge, thus exacerbating corrosion beneath the insulation layer. This can lead to equipment failure and safety issues.

[0005] Physical insulation materials are bulky and are disposed of at the end of their service life, eventually ending up in landfills. Liquid-applied organic insulation materials typically require longer application times and have poorer weather resistance and / or service life, resulting in the need for more material to protect equipment over a given period. Physical insulation materials often require metal sheaths with sharp edges and are not easy to detect early failures when corrosion occurs beneath the insulation layer.

[0006] While existing liquid-based insulation products offer insulation, they require high maintenance costs and downtime due to installation and repairs. Spraying solutions are typically applied in 20 to 50 mil thick coats and require several coats (up to 10 layers) to achieve adequate insulation, each with a long drying time. Furthermore, organic-based liquid-applied insulation coatings have inherent deficiencies in weather resistance and / or long-term durability. Corrosion beneath the insulation layer remains a challenge for both mechanical and liquid insulation solutions.

[0007] CN102585698A discloses a water-based industrial thermal insulation coating that can be used as a thermal insulation covering for heat transfer pipelines. The coating comprises a water-based silicone resin, fillers, and auxiliary materials. SUMMARY

[0008] A silicone-acrylic binder for a thermal barrier coating composition comprises an aqueous emulsion comprising: A) a first acrylic polymer having a Young's modulus of < 50 psi, B) a second acrylic polymer having a Young's modulus of > 5,000 psi, and C) a silicone elastomer. The thermal barrier coating composition comprises A) a first acrylic polymer having a Young's modulus of < 50 psi, B) a second acrylic polymer having a Young's modulus of > 5,000 psi, C) a silicone elastomer, a defoamer, a thermal barrier filler, a metal oxide, and a flash rust inhibitor. Methods of making and using the binder and the thermal barrier coating composition are also disclosed. DETAILED DESCRIPTION

[0009] The binder described above can be made by a method comprising the step of: i) homogenizing starting materials comprising I) a first aqueous emulsion comprising A) a first acrylic polymer having a Young's modulus of < 50 psi, II) a second aqueous emulsion comprising B) a second acrylic polymer having a Young's modulus of > 5,000 psi, and III) a third aqueous emulsion comprising C) a silicone elastomer. Step i) can be performed in any convenient manner using any convenient equipment. Step i) can comprise combining (e.g., by simple mixing) the starting materials comprising I), II), and III). Step i) can also comprise homogenizing by applying a shear force to the starting materials comprising I), II), and III), thereby making an intermediate. In addition to or instead of making an intermediate, the method can comprise adding additional starting materials selected from the group consisting of D) a defoamer, E) a coalescing solvent, F) a pH adjuster, and combinations of two or more thereof. The starting materials for making the binder are detailed below.

[0010] Aqueous acrylic emulsion

[0011] Starting material I) is a first aqueous emulsion. The first aqueous emulsion comprises starting material A) a first acrylic polymer. The first aqueous emulsion also comprises water and a surfactant. The first acrylic polymer has a Young's modulus of < 50 psi. Alternatively, the first acrylic polymer can have a Young's modulus of at most 45 psi, or at most 40 psi, or at most 35 psi, or at most 30 psi; while the first acrylic polymer can have a Young's modulus of at least 5 psi, or at least 6 psi, or at least 17 psi, or at least 20 psi, or at least 30 psi. Alternatively, the first acrylic polymer can have a Young's modulus of 6 psi to < 50 psi, or 6 psi to 40 psi, or 20 psi to 40 psi.

[0012] The first acrylic emulsion can have a particle size Dv50 of 200 nm to 400 nm, measured according to the Particle Size Measurement Test Method described below. Alternatively, the first acrylic emulsion can have a Dv50 of at least 200 nm, or at least 225 nm, or at least 250 nm, or at least 275 nm, or at least 300 nm; while the first acrylic emulsion can have a Dv50 of at most 400 nm, or at most 375 nm, or at most 350 nm, or at most 325 nm, or at most 300 nm.

[0013] The first acrylic emulsion can comprise 54% to < 56% of the first acrylic polymer, 44% to < 46% of water, 0.1% to 0.3% of benzophenone, and 0% to < 0.2% of ammonia. The first aqueous emulsion is commercially available. Suitable examples include RHOPLEX ™ EC-3814 emulsion polymer (wherein the acrylic polymer has a modulus of 17 psi); RHOPLEX ™ 4400 (wherein the acrylic polymer has a modulus of 6 psi); RHOPLEX ™ EC-1791 emulsion polymer (wherein the acrylic polymer has a modulus of 20 psi, a Dv50 average of 350 nm); RHOPLEX ™ EC-1791 QS (wherein the acrylic polymer has a modulus of 20, a Dv50 average of 350 nm); and RHOPLEX ™ 2019 RX aqueous binder (wherein the acrylic polymer has a modulus of 40 psi, a Dv50 average of 250 nm), all of which are commercially available from Dow Chemical Company, Midland, Michigan USA.

[0014] The starting material II) is a second aqueous emulsion. The second aqueous emulsion comprises B) a second acrylic polymer. The second aqueous emulsion further comprises water and a surfactant. The second acrylic polymer has a Young’s modulus of > 5,000 psi. Alternatively, the second acrylic polymer can have a Young’s modulus of > 5,000 psi, or at least 10,000 psi, while the second acrylic polymer can have a Young’s modulus of at most 15,000 psi. Alternatively, the second acrylic polymer can have a Young’s modulus of > 5,000 psi to 15,000 psi; or 5,800 psi to 14,000 psi; or 5,866 psi to 13,835 psi; or 10,000 psi to 15,000 psi.

[0015] The particle size Dv50 of the second aqueous emulsion can be at least 50 nm, or from 90 nm to 300 nm, or from 133 nm to 300 nm, measured according to the Particle Size Measurement Test Method described below. Alternatively, the Dv50 of the second aqueous emulsion can be at least 50 nm, or at least 90 nm, or at least 133 nm, or at least 150 nm, or at least 167 nm, or at least 183 nm, or at least 200 nm; while the Dv50 of the second aqueous emulsion can be at most 300 nm, or at most 250 nm, or at most 233 nm, or at most 217 nm, or at most 200 nm.

[0016] The second aqueous emulsion can comprise from 44% to < 51% of the second acrylic polymer, from 49% to < 56% water, from 0% to < 1% benzophenone, and from 0% to 0.2% ammonia. Alternatively, the second aqueous emulsion can comprise from 50% to less than 51% of the second acrylic polymer, from 49% to less than 50% water, and from 0% to 0.2% ammonia. Alternatively, the second aqueous emulsion can comprise from 44% to less than 46% of the second acrylic polymer, from 54% to < 56% water, from 0.1% to < 1.0% benzophenone, and from 0% to 0.2% ammonia. The second aqueous emulsion is commercially available. Suitable examples include ELASTENE ™ 300, MAINCOTE ™ PR-71 emulsion comprising an acrylic polymer having a modulus of 13,835 psi; and MAINCOTE ™ 5045 comprising an acrylic polymer having a modulus of 5,866 psi, all of which are commercially available from The Dow Chemical Company, Midland, MI, USA.

[0017] Examples of some ethylenically unsaturated monomers that can be used to make the first and second acrylic polymers described above include methyl alkyl acrylates having from 1 to 12 carbon atoms in the alkyl group, such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, isodecyl methacrylate, propyl methacrylate, phenyl methacrylate, and isobornyl methacrylate; alkyl acrylates having from 1 to 12 carbon atoms in the alkyl group, such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, lauryl acrylate, cyclohexyl acrylate, isodecyl acrylate, phenyl acrylate, and isobornyl acrylate; styrene, alkyl substituted styrenes such as alpha-methyl styrene, t-butyl styrene, and vinyl toluene.

[0018] Alternatively, the acrylic polymer can include co-polymerized ethylenically unsaturated carboxylic acid monomers. When such acid monomers are in their deprotonated form, as at a pH below the pKa of the acid monomer itself, they can be referred to as anionic monomers. Such monomers can include, for example, acid functional groups selected from phosphorus-containing acid groups, sulfur-containing acid groups, salts thereof, and combinations thereof. The phosphorus-containing acid functional group can be a (di)hydrogen phosphoric acid group, a phosphonic acid group, a phosphinous acid group, alkali metal salts thereof, other salts thereof, or combinations thereof. Suitable monomers containing phosphorus-containing acid groups can include, for example, (di)hydrogen phosphate esters of alcohols containing a polymerizable vinyl or olefinic group, such as phosphoric acid esters of (meth)acrylic acid hydroxyalkyl esters including hydroxyethyl (meth)acrylate. Other suitable such monomers can include, for example, phosphonic acid functional monomers, such as vinyl phosphonic acid. Alternatively, the phosphorus-containing acid monomer can include phosphoethyl (meth)acrylate.

[0019] The aqueous emulsion starting materials I) and II) of the acrylic polymers are used to make the binder in such amounts that the thermal barrier coating composition made with the binder will comprise a weight ratio of A) the first acrylic polymer to B) the second acrylic polymer (referred to herein as the “A):B) ratio”) of greater than 0 to less than 100 (i.e., >0:<100 to 50:50). Alternatively, the A):B) ratio can be 10:90 to 50:50, or the A):B) ratio can be 20:80 to 50:50, or the A):B) ratio can be 60:40 to 50:50.

[0020] The aqueous emulsions of the acrylic polymers, i.e., starting materials I) and II), can be selected such that the particle size Dv50 of the discontinuous phase of the first aqueous emulsion is at least 1.5 times the particle size Dv50 of the discontinuous phase of the second aqueous emulsion. The particle size ratio can be calculated as the Dv50 of the first aqueous emulsion divided by the Dv50 of the second aqueous emulsion, where the Dv50 is calculated by the Particle Size Test Method described below. Alternatively, the particle size ratio can be at least 1.5, or at least 1.75, or at least 2, or at least 2.25, or at least 2.5, or at least 2.75, or at least 3; while the particle size ratio can be at most 4, or at most 3.5, or at most 3.5, or at most 3.25, or at most 3. It is believed, without wishing to be bound by theory, that when the particle size of II) the second aqueous emulsion is less than the particle size of I) the first aqueous emulsion, the B) second acrylic polymer particles will migrate to the surface of the thermal barrier coating made with the binder and the thermal barrier coating composition described herein, which can minimize the tackiness and / or smudge of the surface of the thermal barrier coating, as measured in the “Examples” described below.

[0021] III) third aqueous emulsion

[0022] The starting material III) is a third aqueous emulsion. The third aqueous emulsion comprises C) a silicone elastomer. The third aqueous emulsion further comprises a surfactant and water. The silicone elastomer in the third aqueous emulsion comprises the reaction product of C-1) and C-2) in the presence of C-3) and C-4), wherein

[0023] C-1) is a dihydroxy-terminated polydiorganosiloxane having a viscosity of > 5,000 mPa.s to < 500,000 mPa.s;

[0024] C-2) is a self-catalyzing crosslinker comprising more than 2 hydroxylamine groups per molecule on average;

[0025] C-3) is a surfactant, and

[0026] C-4) is water. The third aqueous emulsion can further comprise C-5) a stabilizer.

[0027] The starting material C-1) is a dihydroxy-terminated polydiorganosiloxane of the following formula: wherein each R 1 is independently selected from the group consisting of monovalent hydrocarbon groups and monovalent halogenated hydrocarbon groups, and subscript z is an integer having an average value of 500 to 5,000. In this formula, each R 1 is a monovalent hydrocarbon group, such as an alkyl, alkenyl, or aryl group. Suitable alkyl groups can have 1 to 12 carbon atoms, for example, methyl, ethyl, propyl (including n-propyl and isopropyl), butyl (including n-butyl, t-butyl, isobutyl, and sec-butyl), pentyl, hexyl, heptyl, octyl, nonyl, decyl, and dodecyl, including straight chain, branched, and cyclic alkyl groups having 5 to 12 carbon atoms. Suitable alkenyl groups can have 2 to 12 carbon atoms, and include vinyl, allyl, and hexenyl. Suitable aryl groups can have 6 to 12 carbon atoms, and include phenyl, tolyl, xylyl, naphthyl, benzyl, and phenethyl. Any of the monovalent hydrocarbon groups described above can be halogenated, for example, by replacing one or more hydrogen atoms with a halogen atom, such as Cl or F, or F. For example, a halogenated alkyl group, such as chloromethyl or trifluoropropyl, can be used for R 1 . Alternatively, each R 1 may be selected from methyl, ethyl, octyl, trifluoropropyl, vinyl, and phenyl groups. Alternatively, each R 1 may be an alkyl group, such as methyl.

[0028] The starting material C-2) is a self-catalyzing crosslinker comprising more than 2 hydroxylamine groups per molecule. The self-catalyzing crosslinker can have the unit formula: (R 2 3SiO 1 / 2 )2(R 2 2SiO 2 / 2 )a (R 2 R 3 SiO 2 / 2 ) b where each R 2 is an independently selected alkyl group having from 1 to 8 carbon atoms, each R 3 is an independently selected hydroxylamine group of the formula -ONR 2 2, subscript a is 0 or a positive integer and subscript b > 2. In this unit formula, each R 2 is an alkyl group having from 1 to 8 carbon atoms, for example, methyl, ethyl, propyl (including n-propyl and isopropyl), butyl (including n-butyl, t-butyl, isobutyl, and sec-butyl), pentyl, hexyl, heptyl, and octyl, including straight chain, branched, and cyclic alkyl groups having from 5 to 8 carbon atoms. Alternatively, each R 2 may be methyl or ethyl, or methyl. Alternatively, each R 3 may be -ON(CH3)2, -ON(CH2CH3)2, -ON(CH2CH2CH3) 2。 Alternatively, each R 3 may be -ON(CH2CH3)2. Alternatively, subscript a can be from 1 to 10, or from 1 to 5, or from 2 to 4, and alternatively, subscript a can have an average value of 3. Alternatively, subscript b can be from 3 to 10, or from 3 to 7, or from 4 to 6, and alternatively, subscript b can have an average value of 5. The autocatalytic crosslinker can be present in an amount from 1 part by weight to 5 parts by weight of C-2) autocatalytic crosslinker per 100 parts by weight of C-1) diorganopolysiloxane that is terminated with two hydroxyl groups.

[0029] Starting material C-3) is a surfactant. The surfactant can be selected from a non-ionic surfactant, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, or a mixture of two or more thereof. Suitable surfactants are known in the art and are commercially available. Surfactants are disclosed in U.S. Patent 5,944,459 at column 6, line 15 to column 9, line 21, which patent is hereby incorporated by reference. Alternatively, C-3) surfactant can be a non-ionic surfactant, for example, a branched or straight chain polyoxyalkylene, such as a polyoxyalkylene alkyl ether, a polyoxyalkylene sorbitan ester, a polyoxyalkylene ester, a polyoxyalkylene alkyl phenyl ether, or a mixture of two or more thereof. The surfactant can be present in an amount from 0.5 parts by weight to 10 parts by weight, or from 2 parts by weight to 10 parts by weight based on the same basis, per 100 parts by weight of C-1) diorganopolysiloxane that is terminated with two hydroxyl groups.

[0030] The starting material C-4) is water. Water is generally not limited and can be used in pure form (i.e., free of any carrier vehicle and / or solvent) and / or in purified form (i.e., free or substantially free of minerals and / or other impurities). For example, water can be treated or untreated prior to use in the methods and compositions described herein. Examples of processes that can be used to purify water include distillation, filtration, deionization, and combinations of two or more thereof, such that the water can be deionized, distilled, and / or filtered. Alternatively, water can be untreated (e.g., can be tap water, i.e., provided by a municipal water system or well water, used without further purification). Alternatively, water can be purified prior to use herein. The amount of water in the third aqueous emulsion III) can be 0.5 parts by weight to 20 parts by weight, or 2 parts by weight to 10 parts by weight per 100 parts by weight of C-1) dihydroxyl-terminated polydiorganosiloxane, based on the same basis.

[0031] The third aqueous emulsion can optionally further comprise C-5) a stabilizer. Organic amines and inorganic bases are contemplated to be useful stabilizers, which can impart thermal stability. The stabilizer can have the formula (R 4 ) 3-x N(H) x wherein subscript x is 0, 1, 2, or 3. In this formula, R 4 may be an alkyl or aryl group. For example, the stabilizer can be an alkyl amine, such as (CH3)2NH. Alternatively, R 4 may be an alcohol group, such that the stabilizer can be an amino alcohol, such as N(CH2CH2OH)3 or HN(CH2CH2OH)2. Alternatively, the stabilizer can include an organic amine, such as cyclohexylamine, triethylamine, dimethylaminomethylpropanol, diethylaminoethanol, aminomethylpropanol, aminobutanol, monoethanolamine, monoisopropanolamine, dimethylethanolamine, diethanolamine, aminoethylpropanediol, aminomethylpropanediol, diisopropanolamine, morpholine, tris(hydroxymethyl)aminomethane, triisopropanolamine, triethanolamine, aniline, or urea. Inorganic bases, such as ammonia and ammonium carbonate, can also be used as stabilizers.

[0032] Suitable aqueous emulsions for starting material III) are known in the art and can be prepared by known methods, such as those described in U.S. Patent 5,944,459, which is hereby incorporated by reference. Suitable aqueous emulsions for starting material III) include DOWSIL ™8004 waterborne resin, commercially available from The Dow Chemical Company, Midland, Michigan, USA. Without wishing to be bound by theory, it is believed that the inclusion of a third waterborne emulsion in the thermal barrier coating composition enables thicker films to be applied that are capable of drying under ambient conditions without developing alligatoring, as compared to a comparable composition that does not include starting material III). Without wishing to be bound by theory, it is believed that the inclusion of a first waterborne emulsion and / or a third waterborne emulsion in the thermal barrier coating composition enables thicker films to be applied that are capable of drying under ambient conditions without developing alligatoring, as compared to a comparable composition that does not include starting material I) and / or III). Without wishing to be bound by theory, it is believed that the organosilicon elastomer can improve the corrosion resistance of the thermal barrier coating and / or provide the thermal barrier coating with good weatherability, air permeability, and / or hydrophobicity.

[0033] The amounts of starting materials I), II), and III) in the process for making the binder can be 35 to 92 parts by weight of starting material I) first waterborne emulsion, 3 to 53 parts by weight of starting material II) second acrylic emulsion, and 0.1 to 30 parts by weight of starting material III) third waterborne emulsion.

[0034] One or more additional starting materials can optionally be used in the process for making the binder. The optional additional starting materials can be selected from the group consisting of D) a defoaming agent, E) a coalescing solvent, F) a pH adjuster, and combinations of two or more thereof.

[0035] D) defoamer

[0036] Starting material D) is a defoaming agent. Without wishing to be bound by theory, it is believed that a defoaming agent can be added to the binder for the thermal barrier coating composition during processing to prevent or minimize air entrapment. Suitable defoaming agents can include silica and optionally a polyorganosiloxane compound. Suitable defoaming agents are commercially available and include DOWSIL ™ 107F additive, DOWSIL ™ 8590 additive, DOWSIL ™ 8603 additive, and DOWSIL ™ 8610 additive, all of which are commercially available from The Dow Chemical Company, Midland, Michigan, USA. The amount of D) defoaming agent can be 0 to an amount sufficient to provide 10 ppm defoaming agent active (e.g., polyorganosiloxane and / or silica) to the binder, based on the combined weight of starting materials I), III), and C), and II), E), and / or F) when present.

[0037] F) pH adjuster

[0038] The starting material F) is a pH adjuster, which can optionally be added, for example, when the pH of starting material I), starting material II), or both, is less than 8, or less than 8.5. Without wishing to be bound by theory, it is believed that the addition of a pH adjuster can help to stabilize the aerogel in the thermal barrier coating composition. Suitable pH adjusters are commercially available and include bases such as ammonia or ammonium hydroxide, NH4OH. The amount of pH adjuster can be from 0 to an amount sufficient to adjust the pH of the combination of starting materials I) and II), the binder, and / or the thermal barrier coating composition to be > 8, or > 8.5, or from 8.5 to 9.

[0039] Silicone-acrylic binder (binder)

[0040] The binder prepared as described above can comprise: from 40 to 93 parts by weight of A) a first acrylic polymer, from 0.1 to 48 parts by weight (or from 0.11 to 48 parts by weight) of B) a second acrylic polymer, from 0.002 to 14 parts by weight of C) a silicone elastomer, from 0 to 1 parts by weight of D) an antifoam agent, from 0 to 5 parts by weight of E) a coalescing solvent, > 0 parts by weight of F) a pH adjuster (from 0 to 2 parts by weight of a pH adjuster), from 0 to 32 parts by weight of water, and > 0 parts by weight of a surfactant. Those skilled in the art will recognize that the water and surfactant can be introduced via the aqueous emulsions I), II), and III) used to prepare the binder. The binder is in the form of an emulsion or dispersion. Alternatively, the binder can comprise from 20 to 53 parts by weight of A) a first acrylic polymer, from 0.01 to 25 parts by weight of B) a second acrylic polymer, from 0.002 to 11 parts by weight of C) a silicone elastomer, from 0 to 1 parts by weight of D) an antifoam agent, from 0 to 5 parts by weight of E) a coalescing solvent, > 0 parts by weight of F) a pH adjuster, from 27 to 80 parts by weight of K) water, and from 0.0005 to 7 parts by weight of G) a surfactant.

[0041] Process for preparing a thermal barrier coating composition

[0042] The binders described above can be used to prepare a thermal barrier coating composition. For example, a thermal barrier coating composition can be prepared by combining the binders described above with additional starting materials selected from the group consisting of G) a surfactant, H) a thermal barrier filler, I) a metal oxide, J) a flash rust inhibitor, K) water, L) a rheology modifier, and combinations of two or more thereof. Alternatively, the starting materials described above can be used in a method for preparing a thermal barrier coating, whether or not a binder is prepared. For example, a method for preparing a thermal barrier coating composition can comprise:

[0043] 1) homogenizing starting materials comprising:

[0044] I) a first aqueous emulsion comprising A) a first acrylic polymer, a first surfactant, and water;

[0045] II) a second aqueous emulsion comprising B) a second acrylic polymer, a second surfactant, and water;

[0046] III) a third aqueous emulsion comprising C) a silicone resin, a third surfactant, and water;

[0047] Optionally 2) during and / or after step 1), adding additional starting materials selected from the group consisting of D) a defoaming agent, E) a coalescing solvent, F) a pH adjuster, G) an additional surfactant, H) a thermally insulating filler, I) a metal oxide, and combinations of two or more thereof. The first surfactant, the second surfactant, and the third surfactant can be the same or different, and can be as described and exemplified herein for starting material G).

[0048] Alternatively, a method for making a thermal barrier coating composition can comprise:

[0049] 1) carrying out the above-described method for making a binder,

[0050] Optionally 2) during and / or after step 1), adding G) an additional surfactant,

[0051] 3) adding H) a thermally insulating filler to the binder made in step 1) or step 2) and homogenizing to make a filled intermediate; and

[0052] 4) before, during, or after any of steps 1) to 3), adding to the filled intermediate a slurry comprising I) a metal oxide, and a solution or slurry comprising J) a flash rust inhibitor, and homogenizing,

[0053] Optionally 5) when the pH of I) the first aqueous emulsion is <8, II) the pH of the second aqueous emulsion is <8, or the pH of both I) and II) is <8, adding F) a pH adjuster in step 1);

[0054] 6) adding D) a defoaming agent before, during, and / or after adding the thermally insulating filler in step 3).

[0055] The method can optionally further comprise adding additional starting materials selected from the group consisting of D) an additional defoaming agent, E) a coalescing solvent, and combinations thereof. The method can optionally further comprise adding L) a rheology modifier after step 2). The method can further comprise adding additional K) water.

[0056] Alternatively, and more specifically, the above-described method for preparing a thermal barrier coating composition can comprise:

[0057] optionally i) combining (e.g., by simple mixing) I) the first aqueous emulsion, II) the second aqueous emulsion, and III) the third aqueous emulsion;

[0058] ii) homogenizing I) the first emulsion, II) the second emulsion, and III) the third aqueous emulsion, thereby preparing a homogenized intermediate, and then

[0059] optionally iii) adding D) an antifoam agent,

[0060] optionally iv) adjusting the pH by adding F) a pH adjuster; thereby forming a premix,

[0061] v) mixing the premix,

[0062] optionally vi) adding additional D) antifoam agent to the premix,

[0063] optionally vii) adding E) a coalescing solvent to the premix,

[0064] viii) adding V) a slurry comprising I) metal oxide to the premix,

[0065] ix) adding J) a flash rust inhibitor (either neat or as a dispersion or solution of the flash rust inhibitor in water) to the premix,

[0066] optionally x) adding IV) a slurry or solution comprising G) additional surfactant to the premix,

[0067] optionally xi) adding E) a coalescing solvent to the premix, if no coalescing solvent was added in step vii),

[0068] xii) adding H) a thermal insulation filler comprising hydrophobic aerogel to the premix and mixing until the thermal insulation filler is wetted and evenly dispersed in the premix,

[0069] optionally xiii) adding K) water,

[0070] optionally xiv) adding L) a rheology modifier, and

[0071] optionally xv) adding additional water. The starting materials I), II), III), A), B), C), D), E), and F) used in the above-described method for preparing a thermal barrier coating composition are described in detail above. Additional starting materials for preparing a thermal barrier coating composition are detailed below.

[0072] G) surfactant

[0073] Starting material G) is a surfactant that can be optionally added to the thermal barrier coating composition in addition to any surfactants present in starting materials I), II), and III). The surfactant can be nonionic, cationic, anionic, or amphoteric. Alternatively, starting material G) can include a nonionic surfactant. Without wishing to be bound by theory, it is believed that the addition of a surfactant, such as a nonionic surfactant, in addition to any surfactants present in the above-described aqueous emulsions I), II), and III), can facilitate the dispersion of H) the thermal barrier filler (e.g., the hydrophobic aerogel) in the thermal barrier coating composition and / or improve the corrosion resistance of the thermal barrier coating on the metal substrate. The surfactant can be added in pure form. Alternatively, the G) surfactant can be dispersed in water and delivered as a slurry or solution of IV) water and G) surfactant.

[0074] The surfactant that can be added to the thermal barrier coating composition can be a nonionic surfactant. Some suitable nonionic surfactants that can be used include polyoxyethylene alkyl ethers (such as lauryl, cetyl, stearyl, or octyl), polyoxyethylene alkyl phenol ethers, alkyl glycosides, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitan monooleate, polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl esters, polyethylene glycols (such as polyethylene glycol having 23 ethylene oxide units), polypropylene glycol, diethylene glycol, ethoxylated trimethyl nonanol, tristyrlphenol ether (TSP), distyrylphenol ether (DSP), and polyoxyalkylene glycol-modified polysiloxane surfactants.

[0075] Commercially available nonionic surfactants include compositions such as: (i) 2,6,8-trimethyl-4-nonyl polyethoxyethanol (6EO) and (10EO) sold under the names TERGITOL ™ TMN-6 and TERGITOL ™ TMN-10; (ii) C 11-15 secondary alkyl polyoxyethylene ethers (e.g., sold under the name TERGITOL ™ 15-S-7, TERGITOL ™ 15-S-9, and TERGITOL ™ 15-S-15 (HL value 15.4) sold under the names SURFADONE® C 11-15 secondary alcohol ethoxylates 7EO, 9EO, and 15EO) by Dow Chemical Company, Midland, MI, USA under the trade name ECOSURF ™ EH-40 and TERGITOL ™ 15-S-12, TERGITOL ™15-S-30 and TERGITOL ™ 15-S-40 Other C 11-15 Secondary alcohol ethoxylate; sold by Dow Chemical Company under the name TRITON ™ X-405 Octylphenyl polyoxyethylene (40) ether; (iii) nonylphenyl polyoxyethylene (10) ether sold by Stepan Company under the name MAKON ™ 10; (iv) ethoxylated alcohol sold by Henkel Corp. / Emery Group, Cincinnati, Ohio, USA under the name Trycol 5953; (v) ethoxylated alcohol sold by Croda Inc., Edison, New Jersey, USA under the name BRIJ ™ L23 (HLB value 16.9) and BRIJ ™ L4 (HLB value 9.7) ethoxylated alcohol sold by Dow Chemical Company under the name TRITON ™ 23 polyoxyethylene 23 laureth-23 commercially sold by ICI Surfactants, Wilmington, Delaware, USA; and RENEX ™ 30, polyoxyethylene ether alcohol sold by ICI Surfactants, Wilmington, Delaware, USA; (vii) alkyl-keto alcohol polyglycol ethers such as GENAPOL ™ UD 050 (HLB value 11.4) and GENAPOL ™ UD 110 (HLB value 14.4), (viii) alkyl polyglycol ethers based on C10-Guerbet alcohol and ethylene oxide such as LUTENSOL ™ XP 79, and (ix) alkyl polyglycosides such as Glucopon ™ sold by BASF Corporation; and alkylglucosides such as EcoSense ™ decyl, lauryl, and coco glucosides sold by Dow Chemical Company, Midland, Michigan, USA under the name Ecosense. Other commercially available nonionic surfactants include TERGITOL ™ 15-S-5, which has an HLB value of 10.5; Lutensol XP 50 (HLB value 10) and Lutensol XP 140 (HLB value 16).

[0076] Suitable nonionic surfactants also include poly(oxyethylene)-poly(oxypropylene)- poly(oxyethylene) triblock copolymers. Poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) triblock copolymers are also commonly referred to as poloxamers. Poloxamers are nonionic triblock copolymers consisting of a central polyoxypropylene (poly(propylene oxide) hydrophobic chain flanked by two polyoxyethylene (poly(ethylene oxide) hydrophilic chains. Poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) triblock copolymers are commercially available from BASF, Florham Park, New Jersey, USA and are sold under the trade name PLURONIC® ™ Such as PLURONIC ™ L61, L62, L64, L81, and P84 are sold.

[0077] The nonionic surfactant can also be a silicone polyether (SPE). Silicone polyethers as surfactants can have a rake structure in which polyoxyethylene or polyoxyethylene- polyoxypropylene copolymer units are grafted to a siloxane backbone, or the SPE can have an ABA block copolymer structure in which A represents a polyether moiety and B represents a siloxane moiety of the ABA structure. Alternatively, the SPE can have a resin structure such as a polyorganosilicate resin having polyether groups bonded to silicon atoms therein. Suitable SPEs include DOWSIL ™ OFX-5329 fluid. Alternatively, the nonionic surfactant can be selected from the group consisting of polyoxyalkylene-substituted silicones, silicone alkanolamides, silicone esters, and silicone glycosides. Such organosilicon-based surfactants are useful in forming such aqueous emulsions and are known in the art and have been described in, for example, U.S. Patent 4,122,029 to Gee et al., U.S. Patent 5,387,417 to Rentsch, and U.S. Patent 5,811,487 to Schulz et al. Other organosilicon polyether surfactants are known in the art and are also commercially available, for example, DOWSIL ™ 502W additive and DOWSIL ™ 67 additive is commercially available from Dow Silicones Corporation, Midland, Michigan, USA.

[0078] Alternatively, the nonionic surfactant can comprise a polyvinyl alcohol compound. Polyvinyl alcohol compounds are known in the art and are disclosed, for example, in U.S. Patent Application Publication 2007 / 0099007 at paragraphs

[0172] and

[0173] . Polyvinyl alcohol compounds can be prepared by saponification of polyvinyl acetate, so up to 15% of polyvinyl acetate can remain in the polyvinyl alcohol compound used herein. Alternatively, the polyvinyl alcohol compound can be 88% to 92% polyvinyl alcohol (with the balance being 12% to 8% polyvinyl acetate). The polyvinyl alcohol compound can have a minimum viscosity of 5 cP at 4% aqueous solution at 20 °C.

[0079] Anionic surfactants include (i) sulfonic acids and their salt derivatives, including alkyl or aralkyl (e.g., alkyl naphthalene or alkyl diphenyl ether) sulfonic acids having at least 6 carbon atoms in the alkyl substituent, and their salts, such as dodecylbenzene sulfonic acid and its sodium or amine salts; (ii) alkyl sulfates having at least 6 carbon atoms in the alkyl substituent, such as sodium lauryl sulfate; (iii) sulfates of polyoxyethylene monoalkyl ethers; (iv) long chain carboxylic acid surfactants, such as lauric acid, stearic acid, oleic acid, and their alkali metal and amine salts. Some other examples of anionic surfactants are: alkali metal sulfosuccinates; sulfonated glycerol esters of fatty acids, such as sulfonated monoglycerides of coconut oil acid; salts of sulfonated monovalent alcohol esters, such as sodium oleylisothionate; amides of sulfamic acid, such as sodium oleylmethyltauride; sulfonated products of fatty acid nitriles, such as palmityl nitrile sulfonate; sulfonated aromatic hydrocarbons, such as sodium alpha naphthalene monosulfonate; condensation products of naphthalene sulfonic acids with formaldehyde; sodium octahydroanthracene sulfonate; alkali metal alkyl sulfates; ether sulfates having an alkyl group of eight or more carbon atoms, such as sodium lauryl ether sulfate; and alkyl aryl sulfonates having one or more alkyl groups containing eight or more carbon atoms, such as the neutral salt of hexadecyl benzene sulfonic acid and C 20 alkyl benzene sulfonic acid.

[0080] Commercial anionic surfactants that can be used include sodium dodecylbenzene sulfonate, sold under the trade name SIPONATE ™ DS-10 by Alcolac Inc., Baltimore, Maryland; sodium salts of alkyl alkoxylate sulfates, sold under the trade name DOWFAX ™ AS-801 by Dow Chemical Company, Midland, Michigan, USA; sodium n-hexadecyldiphenyloxide disulfonate, sold under the trade name DOWFAX ™8390 sold; sodium salt of a secondary alkane sulfonate, sold under the trade name HOSTAPUR ™ SAS 60 sold; N-acyl taurate, such as sodium N-lauroyl methyl taurate, sold under the trade name NIKKOL LMT by Nikko Chemicals Company, Ltd., Tokyo, Japan ™ sold; and linear alkyl benzene sulfonic acid, sold under the trade name BIO-SOFT by Stepan Company, Northfield, Illinois ™ S-100. Other suitable surfactants include sodium alkyl sulfonates (such as Hostapur ™ SAS-30) and triethanolamine dodecylbenzenesulfonate (such as BIO-SOFT ™ N 300).

[0081] Cationic surfactants useful herein include compounds bearing a positively charged quaternary ammonium hydrophilic moiety in the molecule, such as the quaternary ammonium salts represented by R 8 R 9 R 10 R 11 N + X - wherein R 8 to R 11 is an alkyl group containing 1 to 30 carbon atoms, or an alkyl group derived from tallow, coconut oil, or soybean; and X is a halogen, for example, chloride or bromide. Alternatively, the quaternary ammonium compound can be an alkyltrimethylammonium and dialkyldimethylammonium halide or acetate or hydroxide having at least 8 carbon atoms in each alkyl substituent. Dialkyldimethylammonium salts represented by R 12 R 13 N + (CH3)2X - wherein R 12 and R 13 are alkyl groups containing 12 to 30 carbon atoms, or an alkyl group derived from tallow, coconut oil, or soybean; and X is a halogen as described above. Monoalkyltrimethylammonium salts can be used and are represented by R 14 N+(CH3)3X’ - wherein R 14alkyl groups containing 12 to 30 carbon atoms or alkyl groups derived from tallow, coconut oil, or soybean; and X' is a halogen, acetate, or hydroxide.

[0082] Representative quaternary ammonium halide salts are dodecyltrimethylammonium chloride / lauryltrimethylammonium chloride (LTAC), hexadecyltrimethylammonium chloride (CTAC), didodecyldimethylammonium bromide, hexadodecyl dimethylammonium chloride, hexadodecyl dimethylammonium bromide, octadecyl dimethylammonium chloride, disaccharide dimethylammonium chloride, and didodecyl dimethylammonium chloride. These quaternary ammonium salts are available under trademarks such as ADOGEN ™ and VARIQUAT ™ from Evonik of Essen, Germany, and ARQUAD ™ are commercially available from Nouryon.

[0083] Other suitable cationic surfactants that can be used include fatty acid amines and amides and their salts and derivatives, such as aliphatic fatty amines and derivatives thereof. AMMONYX ™ .

[0084] H) thermal barrier filler

[0085] The starting material H) is a thermal insulation filler that can be used to reduce the thermal conductivity of a thermal insulation coating layer prepared from the thermal insulation coating composition, to improve the hydrophobicity of the thermal insulation coating layer, to improve the thick film application of the thermal insulation coating layer, or a combination of the foregoing. The thermal insulation filler can comprise, or can consist essentially of, or can consist of, a hydrophobic aerogel. The term "aerogel" is used to describe a synthetic, highly porous, ultra-lightweight material that is derived from a gel in which the liquid component of the gel has been replaced with a gas (e.g., air). In other words, an aerogel is a gel in which the dispersion medium is a gas. Historically, the most common method of preparation has been to dry a wet sol-gel at a temperature above the critical temperature and at a pressure above the critical pressure. This drying process drives off the liquid, e.g., water, contained in the gel and produces a porous structure without damaging the solid matrix structure of the gel. Up to 99.98% of the volume of the aerogel can be comprised of pores. Thus, for example, up to 99.98% by volume of the aerogel, such as from 90% to 98.5% by volume or about 97% by volume, can be air. Aerogels are open-cell solids and dry materials that are either microporous or nanoporous. Typically they comprise a network of porous solids, and because of this structure, they are ultra-lightweight. The resulting aerogel, in addition to being low density, has thermal insulation properties, i.e., low thermal conductivity. Other manufacturing methods are now used to produce similar products.

[0086] Aerogels can be based on inorganic or organic materials such as silica, magnesium oxide, titanium dioxide, zirconium oxide, aluminum oxide, chromium oxide, tin dioxide, lithium dioxide, cerium oxide, and vanadium pentoxide, as well as combinations of any two or more thereof, and organic-carbon-containing polymers (carbon aerogels) or resorcinol-formaldehyde or melamine-formaldehyde aerogel particles. Suitable hydrophobic aerogel particles are commercially available, and methods for making suitable hydrophobic aerogels are known (see, e.g., PCT Patent Application Publications WO 99 / 36355 A2, WO 99 / 36356 A2, WO 99 / 36479 Al, WO 98 / 45210 A2, WO 98 / 45035 Al, WO 98 / 45032 Al, WO 96 / 18456 A2, and U.S. Patent Application Publication 2021 / 0032499).

[0087] H) The amount and type of thermal insulation filler is generally related to thermal conductivity, and the selection of thermal insulation filler can directly affect corrosion resistance. The nanoporous (90% to 95%) structured silica aerogel included has a methylation (hydrophobic) surface treatment and is >90% air (740 m 2 / g surface). In the thermal barrier coating composition of the present invention, the specifications for this filler can include: pore size 20 nm to 60 nm, or 20 nm; particle size 0.1 mm to 0.7 mm; density 0.12 g / cm 3 to 0.15 g / cm 3 . A suitable silica aerogel has a CAS number of 102262-30-6. Alternatively, the particle size of the hydrophobic aerogel can be 2 microns to 1.2 mm. Suitable hydrophobic aerogels are commercially available, such as ENOVA ™ IC-3100, ENOVA ™ IC-3110, and ENOVA ™ IC-3120 from Cabot Corporation, Alpharetta, Georgia, USA.

[0088] Alternatively, in the thermal barrier coating composition of the present invention (and the binder described above), in addition to or in place of the hydrophobic aerogel described above, a hollow non-porous thermal insulation filler can be used. The thermal barrier coating composition described herein can include a hollow non-porous thermal insulation filler, such as SPHERICEL ™ hollow glass microspheres from Potters Industries or 3M ™Glass bubbles, which are hollow glass spheres having a density of 0.125 g / cc to 0.6 g / cc and a median particle size of 18 microns to 65 microns, or polymer bubbles that can be able to expand at different temperatures, such as EXPANCEL® available from Nouryon, Amsterdam, Netherlands ™ Microspheres. Alternatively, Q-CEL® can be used ™ Hollow inorganic microspheres or Extendospheres ™ (available from Sphere One, Chattanooga, Tennessee, USA), which are low density, high strength hollow ceramic beads. Hollow non-porous thermal insulation fillers, hydrophobic aerogels, and I) metal oxides are different from each other.

[0089] I) metal oxide

[0090] Metal oxides can be added to the thermal barrier coating composition to provide barrier properties, to provide color (i.e., white), to improve corrosion resistance, to improve hydrophobicity, to improve adhesion, to provide temperature resistance, to act as a sunblock, and / or to reflect ultraviolet light. Examples of metal oxides are titanium dioxide, zirconium dioxide, iron oxides (including micaceous iron oxide), zirconium silicate, manganese oxides, and combinations thereof. Alternatively, the metal oxide can comprise titanium dioxide. Suitable metal oxides are known in the art and are commercially available, for example, described in U.S. Patent Application Publication 2021 / 0269359 at paragraph

[0017] as an infrared sunblock.

[0091] J) flash rust inhibitor

[0092] Starting material J) is a flash rust inhibitor that can be added to the thermal barrier coating composition for inhibiting flash rusting, particularly before removal of water, when the thermal barrier coating composition, which can be in the form of an aqueous emulsion, is applied to a metal substrate, as described below. Suitable flash rust inhibitors are known, for example, from U.S. Patent Application Publication 2021 / 0380840 Al at paragraph

[0031] . The flash rust inhibitor can be selected from zinc phosphate tetrahydrate, zinc orthophosphate, zinc phosphate, aluminum dihydrogen phosphate, polyaniline / zinc / cerium nitrate, zinc tannate, magnesium tannate, zinc phosphate aluminum tripolyphosphate (Zn3(PO4)2@AlH2P3O 10 ), aluminum tripolyphosphate (AlH2P3O 10 .2H2O), zinc oxide, or combinations thereof.

[0093] Alternatively, the flash rust inhibitor can comprise sodium nitrite. Sodium nitrite can prevent flash rusting in direct to metal (DTM) applications. Sodium nitrite can be delivered in a carrier. For example, sodium nitite can be delivered as a dispersion in water, such as 15% NaNCb and 85% water.

[0094] K) water

[0095] The starting material K) is water. Water is present in the binder and thermal barrier coating composition. Water can be incorporated via delivery of the starting materials A), B), and C), which are provided as aqueous emulsion starting materials I), II), and III), respectively. Alternatively, additional water can be added in a separate additional step during the process for making the binder and / or thermal barrier coating composition. Water is generally not limited, and can be used in pure form (i.e., free of any carrier vehicle and / or solvent) and / or in purified form (i.e., free or substantially free of minerals and / or other impurities). For example, the water can be treated or untreated prior to use in the processes and compositions described herein. Examples of processes that can be used to purify water include distillation, filtration, deionization, and combinations of two or more thereof, such that the water can be deionized, distilled, and / or filtered. Alternatively, the water can be untreated (e.g., can be tap water, i.e., provided by a municipal water system or well water, used without further purification). Alternatively, the water can be purified prior to use herein.

[0096] L) rheology modifier

[0097] A rheology modifier can be used to stabilize the H) hydrophobic aerogel thermal insulation filler in the (aqueous) thermal barrier coating composition; for example, to provide sag resistance, to improve the stability of the dispersed thermal insulation filler, and / or to provide workability (thick film application). Suitable rheology modifiers can comprise a polyurethane resin, a polyacrylic acid, a copolymer of methacrylic acid and an acrylic ester, or fumed silica. Alternatively, the rheology modifier can comprise a polyurethane resin (in an amount of 17% to 25%, or 17% to 18%, or 22% to 25%), gluconic acid (in an amount of 0% to 5%, or 3% to 5%), an enzyme modified starch (in an amount of 0% to 5%, or 4% to 5%), and water (in an amount of 75% to 80%, or 78% to 80%, or 75% to 78%). Suitable rheology modifiers are commercially available, such as ACRYSOL ™ TT-615 thickener, ACRYSOL ™ RM-12W, RM-8W, and RM-995.

[0098] Optional starting materials

[0099] The thermal barrier coating composition can optionally comprise one or more additional starting materials. For example, the thermal barrier coating composition can optionally further comprise a colorant, such as calcium carbonate or a (non-metal) oxide, such as mica (e.g., white mica or phlogopite).

[0100] In selecting the starting materials for the thermal barrier coating compositions described herein, there can be overlap between the types of starting materials, as certain starting materials described herein can serve more than one function. For example, calcium carbonate can be used as a colorant and / or a sunblock. In adding additional starting materials to the composition, the additional starting materials are different from one another.

[0101] Thermal barrier coating composition

[0102] The thermal barrier coating compositions described above can be prepared using the starting materials described above by the methods described above. The thermal barrier coating composition can comprise: 33% to 78% of A) a first acrylic polymer, 0.1% to 43% of B) a second acrylic polymer, 0.005% to 11% of C) a silicone elastomer, 0% to 1% of D) a defoamer, 0% to 5% of E) a coalescing solvent, 0% to 1% of F) a pH adjuster, 0% to 7% of G) a surfactant, 2% to 30% of H) a thermal barrier filler (e.g., a hydrophobic aerogel), 2.5% to 10% of I) a metal oxide, 0.1% to 1.2% of J) a flash rust inhibitor, 0% to 28% of K) water, and 0% to 5% of L) a rheology modifier. Alternatively, the thermal barrier coating composition can comprise: 17% to 45% of A) a first acrylic polymer, 0.004% to 25% of B) a second acrylic polymer, 0.003% to 11% of C) a silicone elastomer, 0% to 1% of D) a defoamer, 0% to 5% of E) a coalescing solvent, 0% to 1% of F) a pH adjuster, >0.00008% to 10% of G) a surfactant, 2% to 30% of H) a thermal barrier filler, 2.5% to 10% of I) a metal oxide, 0.1% to 1.2% of J) a flash rust inhibitor, 27% to 80% of K) water, and 0% to 5% of L) a rheology modifier.

[0103] Method of use of the composition

[0104] The thermal barrier coating compositions described above can be applied to the surface of the equipment to be thermally insulated in various ways. The composition can be applied in a single coating, multiple coatings by spraying, brushing or rolling, injected or cast into a mold and shaped to obtain sufficient thermal insulation. The equipment to be thermally insulated can be, for example, a storage tank, a pipeline, a vessel, a furnace, a valve, a boiler, an oven, a liquefied gas container, or a cooling unit. The surface of the equipment to be thermally insulated can comprise a metal, for example steel, as a construction material thereof.

[0105] A method of insulating equipment can comprise: i) applying the above-described insulating coating composition to the surface of the equipment in a layer, and ii) removing water from the insulating coating composition, thereby forming an insulating coating on the surface of the equipment. The amount of insulating coating composition that can be applied in step 1) is sufficient to provide an insulating coating of at least 390 mils, or 390 mils to 400 mils in thickness in a single coat on a horizontal surface, or at least 250 mils, or 250 mils to 260 mils in thickness in a single coat on a vertical surface. The method can optionally further comprise repeating steps i) and ii) one or more times to increase the thickness of the insulating coating. The method can optionally further comprise applying a primer to the surface prior to step i). However, a primer is not necessary and the insulating coating composition can be applied directly to the metal surface to form an insulating coating that adheres to the metal surface and provides corrosion resistance. The method can optionally further comprise applying a topcoat over the insulating coating prepared as described above. However, a topcoat is not necessary.

[0106] Examples

[0107] The following examples are provided to illustrate the application to one of ordinary skill in the art and are not to be construed as limiting the scope of the application as set forth in the appended claims. The starting materials used in these examples are summarized in Table 1.

[0108]

[0109]

[0110]

[0111] In this Example 1 of the application, an insulating coating composition was prepared as follows: First, a binder was prepared by charging a container with RHOPLEX ™ EC-1791 (432.00 g; 59.11 wt%), MAINCOTE ™ PR-71 (108.00 g; 14.78 wt%), DOWSIL ™ 8004 waterborne resin (56.10 g; 7.68 wt%) and deionized water (133.00 g; 18.19 wt%) were charged to a container and the contents were stirred with a propeller blade on a Lightning II mixer at 250 rpm. Next, DOWSIL ™ 8590 additive (1.79 g; 0.24 wt%) was charged to the container, and the contents were continued to be stirred with a propeller blade on a Lightning II mixer at 250 rpm until the resulting mixture was uniform (40 minutes in this example).

[0112] The thermal barrier coating composition was prepared using the binder (described above) as follows: 730.89 g of the binder (77.43 wt.%) prepared as described above and UCAR ™ Filmer IBT (8.10 g; 0.86 wt.%) was added to the binder and the resulting mixture was stirred with a propeller blade on a Lightning II mixer at 250 rpm. Ti Pure ™ R-741 titanium dioxide slurry (52.81 g; 5.60 wt.%) was then added, followed by 15 wt.% aqueous sodium nitrite solution (8.33 g; 0.89 wt.%), and mixing was continued. Next, 25% Pluronic P84 aqueous solution (28.89 g; 3.06 wt.%) was added. The container lid was put on and the contents were mixed at 250 rpm for 40 minutes until the resulting composition was uniform. The mixing speed was then increased to 400 rpm. The thermal insulation filler Enova IC-3110 aerogel (108.00 g; 11.44 wt.%) portion was added slowly, increasing the speed to 800 rpm as needed to maintain vortex flow in the binder. Next, ACRYSOL ™ RM-12W rheology modifier (5.71 g; 0.60 wt.%) was added and ACRYSOL ™ RM-8W rheology modifier (1.18 g; 0.12 wt.%) was then added and mixed at 800 rpm for 10 minutes.

[0113] In this Inventive Example 2, the thermal barrier coating composition was prepared as described in Inventive Example 1, except that RHOPLEX ™ EC-1791 was replaced with RHOPLEX ™ 2019RX, and some of the starting materials were used in different amounts, as shown in Table 2 below.

[0114] In this Comparative Example 1, RHOPLEX ™ EI-2000 (350 g; 80.46 wt.%) and UCAR ™ Filmer IBT (5.25 g; 1.21 wt.%) were combined and stirred with a propeller blade on a Lightning II mixer at 250 rpm. Next, DOWSIL ™ 8590 additive (1.05 g; 0.24 wt.%) was charged to the container and the contents were stirred with a propeller blade on a Lightning II mixer at 250 rpm until the resulting mixture was uniform. Next, Ti Pure ™R-741 titania slurry (31.01 g; 7.13 wt%), followed by addition of 15 wt% aqueous sodium nitrite solution (3.84 g; 0.88 wt%) and continue mixing. Add 25 wt% PLURONIC ™ P84 aqueous solution (5.46 g; 1.25 wt%). Cap the container and continue mixing at 250 rpm for 40 minutes until the binder blend is uniform. Then increase the mixing speed to 400 rpm.

[0115] Next, add ENOVA ™ IC-3110 aerogel (35.56 g; 8.18 wt%), increase the speed as needed to 800 rpm to maintain vortex in the binder blend. Add ACRYSOL ™ RM-12W rheology modifier (1.88 g; 0.43 wt%) and add ACRYSOL ™ RM-8W rheology modifier (0.94 g; 0.22 wt%) and then mix the contents of the container at 800 rpm for 10 minutes.

[0116] In this Comparative Example 2, RHOPLEX ™ EC-3814 (350.00 g; 75.57 wt%) and DOWSIL ™ 6694 (28.00 g; 6.05 wt%) are added to the container and stirred with the propeller blade on a Lightning II mixer at 250 rpm. Add DOWSIL ™ 8590 additive (1.13 g; 0.25 wt%). Add ammonium hydroxide (3.67 g; 0.79 wt%). Stir the contents of the container with the propeller blade on a Lightning II mixer at 250 rpm until the mixture is uniform (40 minutes in this example). Next, add UCAR ™ Filmer IBT (5.25 g; 1.13 wt%) and stir the resulting mixture with the propeller blade on a Lightning II mixer at 250 rpm.

[0117] Next, Ti Pure ™ R-741 titania slurry (33.49 g; 7.23 wt%) is charged to the container, followed by 15 wt% aqueous sodium nitrite solution (4.32 g; 0.93 wt%) and continue mixing. Add 25 wt% PLURONIC ™P84 aqueous solution (5.46 g; 1.18 wt%) and cap the container. Continue mixing at 250 rpm for 40 minutes until the binder blend is uniform. Increase the mixing speed to 400 rpm. Next, add ENOVA ™ IC-3110 aerogel (29.00 g; 6.26 wt%) and increase the speed as needed to 800 rpm to maintain vortex in the binder blend. Next, add ACRYSOL ™ RM-12W rheology modifier (1.88 g; 0.41 wt%) and add ACRYSOL ™ RM-8W rheology modifier (0.94 g; 0.20 wt%) and then mix the resulting mixture at 800 rpm for 10 minutes.

[0118] In this Comparative Example 3, FORMASHIELD ™ 12 (325.00 g; 70.92 wt%) and DOWSIL ™ IE-6683 (64.15 g; 14.00 wt%) are charged to a container and stirred with a propeller blade on a Lightning II mixer at 250 rpm. To the container, add DOWSIL ™ 8590 additive (1.17 g; 0.25 wt%). Continue stirring with a propeller blade on a Lightning II mixer at 250 rpm until the mixture is uniform (40 minutes in this example). Add UCAR ™ Filmer IBT (4.87 g; 1.06 wt%) and stir the mixture with a propeller blade on a Lightning II mixer at 250 rpm.

[0119] Next, add Ti Pure ™ R-741 titanium dioxide slurry (27.58 g; 6.02 wt%) and 15 wt% aqueous sodium nitrite solution (4.29 g; 0.94 wt%) and continue mixing. Add 25 wt% PLURONIC ™ P84 aqueous solution (5.07 g; 1.11 wt%) and cap the container. Continue mixing at 250 rpm for 40 minutes until the binder blend is uniform. Increase the mixing speed to 400 rpm.

[0120] Add ENOVA ™ IC-3110 aerogel (23.50 g; 5.13 wt%) and increase the speed as needed to 800 rpm to maintain vortex in the binder blend. Add ACRYSOL ™RM-12W rheology modifier (1.75 g; 0.38 wt%) and ACRYSOL ™ RM-8W rheology modifier (0.87 g; 0.19 wt%). The resulting mixture was mixed at 800 rpm for 10 minutes.

[0121] In this Comparative Example 4, RHOPLEX ™ 12 (375.00 g; 77.70 wt%) and DOWSIL ™ 8004 aqueous resin (34.81 g; 7.21 wt%) was charged to a container and stirred with a propeller blade on a Lightning II mixer at 250 rpm. DOWSIL ™ 8590 additive (1.23 g; 0.25 wt%) was added. Stirring was continued with a propeller blade on a Lightning II mixer at 250 rpm until the mixture was uniform (40 minutes in this example). UCAR Filmer IBT (5.62 g; 1.17 wt%) was added and the mixture was stirred with a propeller blade on a Lightning II mixer at 250 rpm.

[0122] Next, Ti Pure ™ R-741 titanium dioxide slurry (29.05 g; 6.02 wt%) and 15 wt% aqueous sodium nitrite solution (4.54 g; 0.94 wt%) were added and mixing was continued. 25 wt% aqueous Pluronic P84 solution (5.85 g; 1.21 wt%) was added and the container lid was replaced. Mixing was continued at 250 rpm for 40 minutes until the binder blend was uniform. The mixing speed was increased to 400 rpm.

[0123] Enova IC-3110 aerogel (23.5 g; 4.87 wt%) was added in portions slowly, increasing the speed to 800 rpm as needed to maintain vortex in the binder blend. ACRYSOL ™ RM-12W rheology modifier (2.01 g; 0.42 wt%) and ACRYSOL ™ RM-8W rheology modifier (1.01 g; 0.21 wt%). The resulting mixture was mixed at 800 rpm for 10 minutes.

[0124] In this Comparative Example 5, RHOPLEX ™ EC-1791 (600.00 g; 71.16 wt%) and DOWSIL ™8004 Waterborne resin (63.50 g; 7.53 wt.%) was charged to a container and stirred with a propeller blade on a Lightning II mixer at 250 rpm. DOWSIL ™ 8590 Additive (1.99 g; 0.24 wt.%). Stirring was continued with a propeller blade on a Lightning II mixer at 250 rpm until the mixture was uniform (40 minutes in this example). UCAR Filmer IBT (9.00 g; 1.07 wt.%) was added and the mixture was stirred with a propeller blade on a Lightning II mixer at 250 rpm.

[0125] Next, Ti Pure ™ R-741 titanium dioxide slurry (58.78 g; 6.97 wt.%) and 15 wt.% aqueous sodium nitrite solution (7.59 g; 0.90 wt.%) were added and mixing was continued. 25 wt.% aqueous Pluronic P84 solution (20.33 g; 2.41 wt.%) was added and the container lid was replaced. Mixing was continued at 250 rpm for 40 minutes until the binder blend was uniform. The mixing speed was increased to 400 rpm.

[0126] ENOVA ™ IC-3110 aerogel (76.00 g; 9.01 wt.%) and the speed was increased to 800 rpm as needed to maintain vortex in the binder blend. ACRYSOL ™ RM-12W rheology modifier (4.02 g; 0.48 wt.%) was added and ACRYSOL ™ RM-8W rheology modifier (2.01 g; 0.24 wt.%). The resulting mixture was mixed at 800 rpm for 10 minutes.

[0127] Corrosion ratings and dirt pick up (DPU) were evaluated according to the following test methods. Results are shown in Table 2 below.

[0128]

[0129] In Table 2, 10 indicates the best corrosion rating, i.e., the sample with the least corrosion, and 0 indicates the worst corrosion rating (the sample with the most corrosion); +++ indicates the best performance (best DPU rating), ++ indicates the second best, + indicates the third best, — indicates the worst performance, — indicates the second worst, and - indicates performance worse than + and better than —. Table 2 shows that samples containing A) a first acrylic polymer having a modulus of < 50 psi, a second acrylic polymer having a modulus of > 5,000 psi, and C) a silicone elastomer produced thermal barrier coatings having excellent corrosion resistance under the conditions tested.

[0130] In this Reference Example 3: a sample of thermal barrier coating composition was prepared as follows: First, the binder was prepared by charging RHOPLEX ™ EC-1791 (300.00 g; 46.6 wt%) and MAINCOTE ™ The binder was prepared by charging PR-71 (200.00 g; 31.0 wt%) into a container and agitating with a propeller blade on a Lightning II mixer at 250 rpm. Next, Dowsil 8590 Additive (1.50 g; 0.2 wt%) was charged into the container and agitation of the contents was continued with the propeller blade on the Lightning II mixer at 250 rpm until the resulting mixture was uniform (40 minutes in this example).

[0131] Next, the thermal barrier coating was prepared as follows: 501.50 g of the binder prepared as described above (77.8 wt%) and UCAR ™ Filmer IBT (7.50 g; 1.2 wt%) were combined and agitated with a propeller blade on a Lightning II mixer at 250 rpm. Next, Ti Pure ™ R-741 titanium dioxide slurry (44.30 g; 6.9 wt%) was added, followed by 15 wt% aqueous sodium nitrite solution (5.68 g; 0.1 wt%) and mixing was continued. A 25 wt% aqueous solution of Pluronic P84 (7.80 g; 1.2 wt%) was added, the container was capped, and mixing was continued at 250 rpm for 40 minutes until the mixture was uniform. The mixing speed was increased to 400 rpm. Enova IC-3110 aerogel (56.54 g; 8.8 wt%) was added slowly in portions, and the speed was increased to 800 rpm as needed to maintain vortex in the mixture. ACRYSOL ™ RM-12W rheology modifier (2.69 g; 0.4 wt%) was added dropwise, and ACRYSOL ™ RM-8W rheology modifier (1.34 g; 0.2 wt%) was added dropwise, and the mixture was mixed at 800 rpm for 10 minutes.

[0132] The samples were evaluated for corrosion resistance and stain resistance according to the following test methods. The results are shown in Table 3.

[0133]

[0134] The data in Tables 2 and 3 show that the combination of a first acrylic polymer having a modulus < 50 psi and a second acrylic polymer having a modulus > 5,000 psi provides better performance than samples containing only one of these two acrylic polymers. However, a sample containing a silicone resin in addition to the first acrylic polymer having a modulus < 50 psi and the second acrylic polymer having a modulus > 5,000 psi produced a thermal barrier coating with both good corrosion ratings and good stain resistance, as shown, for example, in Inventive Example 2, which contained DOWSIL ™ 8004, and better corrosion resistance than the comparative examples in Table 3 containing the same two acrylic polymers but without the silicone elastomer. Also, Inventive Example 1 has the same two acrylic polymers as one of the comparative examples in Table 3, however, the data in Table 2 show that Inventive Example 1 has better corrosion resistance and better stain resistance than the comparative example in Table 3 using the same two acrylic polymers but without the silicone elastomer.

[0135] Industrial applicability

[0136] The above examples show that the binder and thermal barrier coating compositions of the present application provide unexpected benefits, namely, good corrosion resistance (10 or 9) corrosion ratings according to the Corrosion Test Method herein and good stain resistance (DPU) ratings according to the Test Method herein. In addition, thermal barrier coatings having low thermal conductivity can be made from the silicone-acrylic binders and thermal barrier coating compositions described herein. For example, without wishing to be bound by theory, it is believed that the thermal barrier coatings have a thermal conductivity > 0.045 W / mK. The single coat thickness of the thermal barrier coating can be up to 400 mils on a horizontal surface, or up to 250 mils on a vertical surface. Alternatively, the single coat thickness can be from 20 mils to 400 mils; or from 80 mils to 400 mils on a horizontal surface. Alternatively, the single coat thickness can be from 20 mils to 250 mils; or from 80 mils to 250 mils on a vertical surface.

[0137] Test methods

[0138] The following test methods were used to measure the properties herein unless otherwise indicated. The samples were coated on metal substrates, dried and corroded according to ASTM B-117. Corrosion was measured according to ASTM Standard D1654 - 08 Standard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments.

[0139] The stain resistance test method was performed as follows:

[0140] 1. Prepare panels. Apply emulsion or emulsion blend with a draw down bar at 4 mils wet film thickness on 3x6 inch chromate pretreated aluminum Q-panel panels. Dry for 7 days at ambient conditions.

[0141] 2. Prepare the stain mixture. Weigh out 10 g of KMI Industrial Minerals MIOX ™ Submicron Type 5 Fe2O3 + 35 g of DI water into a MAX 60 dental cup. Mix with a dental speed mixer at 2,000 rpm for 2 minutes.

[0142] 3. Stain the panels. Drop 0.2 g of the stain mixture onto the panel with a pipette (5 drops with the pipette used for this test). Spread the stain mixture onto the panel with a small foam paint brush, brushing horizontally 10 times in the same path.

[0143] 4. Rinse the panels. Place the stained portion of the panel under a faucet of cold water in a sink and rinse for 10 seconds. Pat dry.

[0144] 5. Compare all panels side by side and rate.

[0145] Modulus measurements of acrylic polymers were performed as follows:

[0146] Films for Young's modulus measurements were prepared by adding 15 g to 20 g of emulsion as is into a 2.5 inch x 3 inch Teflon mold sandwiched between release liners. The films were dried at room temperature for 7 days. The dried films were cut into dumbbells using a DIN S2 standard mold. Strain-stress curves were collected on an MTS Alliance RT-5 instrument at a rate of 20.0 inches / minute using a 100 N load cell. Young's modulus was automatically calculated by the instrument software based on the slope at the low strain region of the strain-stress curve. Measurements were made using 4 dumbbell shaped specimens per material.

[0147] Particle size measurements were performed as follows: Sample preparation method was to dilute 0.1 g of emulsion (corresponding to any of the starting materials I), II), or III) described herein) in 20 mL of water. Particle size was measured using a Mastersizer 3000 from Malvern Instruments. ™3000 laser diffraction particle size analyzer measurements. Average particle size, expressed as volume average median diameter Dv50, was used to characterize the particle size of the first (soft) and second (hard) acrylic polymers. The particle size ratio can be calculated by dividing the Dv50 of the first acrylic polymer by the Dv50 of the second acrylic polymer.

[0148] Definitions and usage of terms

[0149] All amounts, ratios, and percentages herein are by weight unless otherwise indicated by the context of the specification. The articles 'a', 'an', and 'the' each refer to one or more, unless otherwise indicated by the context of the specification. The singular forms 'a', 'an', and 'the' include plural references unless the context of the specification indicates otherwise. The summary of the invention and the abstract are hereby incorporated by reference. The amounts of all starting materials in the compositions total 100%. The transitional phrases "comprising", "consisting essentially of, and "consisting of are used in accordance with the Ninth Edition of the Patent Examining Procedure, Revision 08.2017, last revised January 2018, Chapters §2111.03 I., II., and III. Any feature or aspect of the invention can be used in combination with any other feature or aspect described herein. Abbreviations used herein have the definitions in Table 5.

[0150]

Claims

1. An adhesive comprising: A) First acrylic polymers with a Young's modulus ≤ 50 psi. B) Secondary acrylic polymers with a Young's modulus ≥ 5,000 psi. C) Organosilicon elastomers, said organosilicon elastomers are prepared by reacting a starting material comprising a dihydroxyl-terminated polydiorganosiloxane and a self-catalytic crosslinking agent. G) Surfactants, K) Water, Optionally, D) defoamer, Optionally E) coalescing solvent, and Optional F) pH adjuster.

2. The adhesive of claim 1, wherein the first acrylic polymer has a modulus of 6 psi to 40 psi.

3. The adhesive according to claim 1 or claim 2, wherein the second acrylic polymer has a modulus of 5,800 psi to 14,000 psi.

4. The adhesive according to any one of claims 1 to 3, wherein the dihydroxyl-terminated polydiorganosiloxane has the following formula: ,in Each R 1 The groups composed of monovalent hydrocarbon groups and monovalent halohydrocarbon groups are independently selected, and The subscript z is an integer with an average value between 500 and 5,000.

5. The adhesive according to any one of claims 1 to 4, wherein the self-catalytic crosslinking agent has the unit formula: (R 2 3SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) a (R 2 R 3 SiO 2 / 2 ) b ,in Each R 2 It is an independently chosen alkyl group having 1 to 8 carbon atoms. Each R 3 It is an independently selectable type - ONR 2 2 hydroxylamine group, The subscript 'a' is 0 or a positive integer, and Subscript b > 2.

6. The composition according to any one of claims 1 to 5, wherein the adhesive comprises: 20 to 53 parts by weight of A) the first acrylic polymer, B) The second acrylic polymer, 0.01 parts by weight to 25 parts by weight. 0.002 parts by weight to 11 parts by weight of the organosilicon elastomer described in C), 0 to 1 part by weight of the defoamer described in D) 0 to 5 parts by weight of the coalescence solvent described in E) ≥0 parts by weight of the pH adjuster described in F), 27 to 80 parts by weight of K) water, and 0.0005 parts by weight to 7 parts by weight of the surfactant described in G).

7. A method for preparing the adhesive according to any one of claims 1 to 6, wherein the method comprises: 1) The starting material is homogenized, the starting material comprising: I) A first aqueous emulsion, the first aqueous emulsion comprising A) The first acrylic polymer, The first surfactant, and water; II) The second aqueous emulsion, the second aqueous emulsion comprising B) The second acrylic polymer, The second surfactant, and water; III) A third aqueous emulsion, the third aqueous emulsion comprising C) Polyorganosiloxane elastomers, wherein the polyorganosiloxane elastomers comprise reaction products of the following substances: C-1) The dihydroxy-terminated polydimethylsiloxane C-2) The self-catalytic crosslinking agent, The third surfactant, and water; Optional 2) In the steps 1) During and / or after the process, additional starting materials may be added, the additional starting materials being selected from the group consisting of the defoamer, the coalescing solvent, the pH adjuster, and combinations of two or more of them.

8. A heat-insulating coating composition, said heat-insulating coating composition comprising: A) First acrylic polymers with a modulus ≤ 50 psi. B) Secondary acrylic polymers with a modulus ≥ 5,000 psi. C) Organosilicon elastomers, D) Surfactants K) Water, G) Defoamer, H) Insulating filler, J) Flash rust inhibitor, Optionally I) metal oxides, Optional F) pH adjuster, Optionally E) coalescing solvent, and Optional L) rheology modifier.

9. The heat-insulating coating composition according to claim 8, wherein the composition comprises: 17% to 45% by weight of A) the first acrylic polymer, B) The second acrylic polymer, 0.004% to 25% by weight. 0.003% to 11% by weight of the organosilicon elastomer described in C), 0% to 1% by weight of the defoamer described in D). The coalescence solvent E) is 0% to 5% by weight. The pH adjuster is described in the form of 0% to 1% by weight of F. >0.00008% to 10% by weight of the surfactant described in G), The insulating filler described in H) is 2% to 30% by weight. 2.5% to 10% by weight of the metal oxide described in I), 0.1% to 1.2% by weight of the flash rust inhibitor described in J), 27% to 80% of the water described in K), and 0% to 5% of the rheology modifier described above.

10. The composition according to claim 8 or claim 9, wherein the insulating filler (H) comprises a hydrophobic aerogel.

11. A method for preparing a heat-insulating coating composition, wherein the method comprises: 1) Prepare the adhesive by carrying out the method of claim 7. Optionally 2) Add surfactant G during and / or after step 1). 3) Add H) insulating filler to the binder prepared in step 1) or step 2) and homogenize it to prepare a filling intermediate; and 4) Before, during, or after any of steps 1) to 3), add a slurry containing I) a metal oxide and a solution or slurry containing J) a flash rust inhibitor to the filling intermediate, and homogenize. Optional location 5) when I) The pH of the first aqueous emulsion is <8. II) The second aqueous emulsion has a pH < 8, or I) and II) When both pH values ​​are <8, add pH adjuster F) in step 1). 6) Add defoamer D) before adding the hydrophobic aerogel insulation filler in step 3).

12. The method of claim 11, further comprising adding an additional starting material selected from the group consisting of an additional defoamer, an E) coalescing solvent, additional water, and combinations thereof.

13. The method according to claim 11 or claim 12, wherein the method further comprises adding a rheology modifier after step 2).

14. The method according to any one of claims 11 to 13, wherein the insulating filler in H) comprises a hydrophobic aerogel.

15. A method for insulating equipment, wherein the method comprises: Optionally, a primer may be applied to the metal surface of the equipment; i) Applying the heat-insulating coating composition of any one of claims 8 to 10 in the form of a layer to the metal surface of the device, and ii) Remove water, thereby forming a heat-insulating coating on the metal surface of the device; as well as Optionally iii) repeat steps i) and ii) once or more to increase the thickness of the heat-insulating coating.

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