Compositions containing a thermally conductive filler and a thermally expandable material

Abstract

Disclosed are compositions comprising a thiol-containing compound, an oxidant, a thermally expandable material, and a thermally conductive filler. Also disclosed are coatings formed from the compositions.

Description

COMPOSITIONS CONTAINING A THERMALLY CONDUCTIVE FILLER AND A THERMALLY EXPANDABLE MATERIAL GOVERNMENT CONTRACT

[0001] This disclosure was made with Government support under Government Contract No. NCMS FY2019NMP-FREE LI BATTERIES PHASE III 202050 awarded by the GVSC. The United States Government may have certain rights the subject matter disclosed herein. CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 557,871 and U.S. Provisional Application Serial No. 63 / 691,214, both entitled “Compositions Containing Thermally Conductive Filler and Thermally Expandable Material”, filed on February 26, 2024, and September 5, 2024, respectively, both of which are incorporated herein in their entirety. FIELD

[0003] Thermally insulative compositions and uses thereof are disclosed. BACKGROUND

[0004] Thermal insulation allows for protection of the surrounding battery cells and housing at thermal runaway conditions. The present disclosure is directed toward compositions that are thermally conductive under normal operating conditions but thermally insulative under extreme conditions. SUMMARY

[0005] Disclosed are composition comprising: a thiol-containing compound; an oxidant; a thermally expandable material; and a thermally conductive filler.

[0006] Also disclosed are methods of coating a substrate comprising: contacting a surface of the substrate with any of the thermally expandable coating compositions disclosed herein.

[0007] Also disclosed are substrates comprising a coating formed from one of the thermally expandable coating compositions disclosed herein on a surface of the substrate.

[0008] Also disclosed are batteries comprising a battery cell and a coating formed from one of the thermally expandable coating compositions disclosed herein.

[0009] Also disclosed are vehicles comprising a battery disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 is a schematic of a top-down view of cylindrical battery cells.

[0011] FIG. 2 is a schematic of an exploded isometric view of an array of prismatic battery cells.

[0012] FIG. 3 is a schematic of a front view of an array of pouch battery cells.

[0013] FIG. 4 is a schematic of an isometric view of cylindrical cells positioned in a battery module.

[0014] FIG. 5 is a schematic of an exploded perspective view of a battery pack comprising multiple battery cells.

[0015] FIG. 6 is a schematic of an isometric view of (A) a battery cell, (B) a battery module, and (C) a battery pack.

[0016] FIG. 7 is a schematic of a perspective view of a battery pack.

[0017] FIG. 8 is a schematic of a cell to battery pack configuration.

[0018] FIG. 9 is a schematic of an isometric cut-out view of a cell to chassis battery assembly. DETAILED DESCRIPTION

[0019] Disclosed are compositions comprising, or consisting essentially of, or consisting of: a thiol-containing compound; an oxidant; a thermally expandable material; and a thermally conductive filler. Thiol-Containing Compounds

[0020] As stated above, the composition comprises a thiol-containing compound. The thiol group may be terminal or pendant. Suitable thiol-containing compounds are disclosed in U.S. Patent No. 7,858,703B2, 3:27 to 11:54, the cited portions of which are incorporated herein by reference. The thiol-containing compound may comprise a liquid.

[0021] Suitable thiol-containing compounds useful in the compositions disclosed herein for preparing the thiol-containing polymer include monomers, small molecules, and / or polymers having at least two thiol groups. Useful thiol-containing compounds include those having the formula (I):HS—R1—SH (I) wherein R1may be a C2-6 alkanediyl, a C6-8 cycloalkanediyl, a C6-10 alkanecycloalkanediyl, a C5-8 heterocycloalkanediyl, a substituted C2-6 alkanediyl, a substituted C6-8 cycloalkanediyl, a substituted C6-10alkanecycloalkanediyl, a substituted C5-8heterocycloalkanediyl and / or —-[(CHR3)p—X]q—(CHR3)r—; where, each R3independently may be hydrogen or a methyl; each X independently may be O, S, S—S, NH, and / or N(—CH3); p may be an integer from 2 to 6; q may be an integer from 1 to 5; and r may be an integer from 2 to 10. In examples, each p independently may be 2, 3, 4, 5, and 6. In examples, each p can be the same and can be 2, 3, 4, 5, or 6.

[0022] Further useful dithiols include one or more heteroatom substituents in the carbon backbone, that is, dithiols in which X includes a heteroatom such as O, S, S-S or another bivalent heteroatom radical; a secondary or tertiary amine group, i.e., —NR6—, where R6is hydrogen or methyl; or another substituted trivalent heteroatom. In an example, X is O or S, and thus R1is —-[(—CH2—)p—O—]q—(—CH2—)r— or —[(—CH2—)p—S—]q—(—CH2—)r—. In

[0023] Useful polythiols include but are not limited to dithiols such as 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,3-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,3-pentanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, 1,3-dimercapto-3-methylbutane, dipentenedimercaptan, ethylcyclohexyldithiol (ECHDT), dimercaptodiethylsulfide, methyl- substituted dimercaptodiethylsulfide, dimethyl-substituted dimercaptodiethylsulfide, dimercaptodioxaoctane, 1,5-dimercapto-3-oxapentane and mixtures thereof. The polythiol material can have one or more pendant groups selected from lower alkyl groups, lower alkoxy groups and hydroxyl groups. Suitable alkyl pendant groups include C1-C6linear alkyl, C3- C6branched alkyl, cyclopentyl, and cyclohexyl.

[0024] Useful dithiols include dimercaptodiethylsulfide (DMDS) (p=2, r=2, q=1, X═S); dimercaptodioxaoctane (DMDO) (p=2, q=2, r=2, X=0); and 1,5-dimercapto-3-oxapentane (p=2, r=2, q=1, X═O). It is also possible to use dithiols that include both heteroatom substituents in the carbon backbone and pendant alkyl groups, such as methyl groups. Such compounds include methyl-substituted DMDS, such as HS—CH2CH(CH3)—S—CH2CH2—SH, HS— CH(CH3)CH2—S—CH2CH2—SH and dimethyl substituted DMDS such as HS— CH2CH(CH3)—S—CH(CH3)CH2—SH and HS—CH(CH3)CH2—S—CH2CH(CH3)—SH.

[0025] Two or more different polythiols can be used in the compositions.

[0026] A useful thiol-containing compound may have the structure of formula (II): HS—R1—[—S—(CH2)p—O—(—R2—O—)m—(CH2)q—S—R1—]n—SH (II) wherein R1can be a C2-10n-alkylene, C2-6branched alkylene, C6-8cycloalkylene or C6-10 alkylcycloalkylene group, heterocyclic, —[(—CH2)p—X]q—(—CH2)r; or —[(—CH2)p—X]q— (—CH2)r— in which at least one —CH2— unit is substituted with a methyl group; R2can be a C2-10n-alkylene, C2-6branched alkylene, C6-8cycloalkylene or C6-14alkylcycloalkylene group, heterocyclic, —[(—CH2)p—X]q—(—CH2)r; X can be O, S, S-S and —NR6—; R6can be H or methyl; m is an independently selected rational number from 1 to 50; and n is an independently selected integer from 1 to 60; p is an independently selected integer ranging from 2 to 6; q is an independently selected integer ranging from 1 to 5; and r is an independently selected integer from 2 to 10. In an example of the foregoing polymer, R1is C2-C6 alkyl and R2is C2-C6 alkyl.

[0027] Polyfunctional thiol-containing polymers may have the formula (III) or (IV): B—{R8′CH2CH2—O—(R2—O)mCH2CH2—S—R1—[—S—CH2CH2—O—(R2—O)m—CH2— S—R1]n—SH}z (III) or B—{R8′—S—R1—[—S—CH2CH2—O—(R2—O)m—CH2—S—R1]n—SH}z(IV)m can be structures and values discussed above with reference to Formula II, R8can be a moiety which is reactive with a terminal vinyl group or mercapto group, and z is an integer from 3 to 6.

[0028] Other suitable thiol-containing monomers for use in the compositions disclosed herein include, for example, mercapto-propionates, mercapto-acetates, mercapto-acrylates, and combinations of any of the foregoing.

[0029] Examples of suitable mercapto-propionates for use in the compositions disclosed herein include pentaerythritol tetra(3-mercapto-propionate) (PETMP), trimethylol-propane tri(3- mercaptopropionate) (TMPMP), glycol di(3-mercaptopropionate) (GDMP), tris[2-(3-mercapto- propionyloxy)ethyl]isocyanurate (TEMPIC), di-pentaerythritol hexa(3-mercaptopropionate) (di- PETMP), tri(3-mercaptopropionate) pentaerythritol, triethylolethane tri-(3-mercaptopropionate), and combinations of any of the foregoing.

[0030] Examples of suitable polymeric thiols for use in the compositions disclosed herein include ethoxylated trimethylolpropane tri(3-mercaptopropionate), polycaprolactone tetra-3- mercaptopropionate, and combinations thereof.

[0031] Examples of suitable mercapto-acetates for use in the compositions disclosed herein include pentaerythritol tetramercaptoacetate (PRTMA), trimethylolpropane trimercaptoacetate (TMPMA), glycol dimercaptoacetate (GDMA), ethyleneglycol dimercaptoacetate, di-trimethylolpropane tetramercaptoacetate, and combinations of any of the foregoing.

[0032] Examples of suitable mercapto-acrylates for use in the compositions disclosed herein include pentaerythritol tetra-acrylate, tris[2-(3-mercaptopropionyloxy)ethyl]isocyanurate, 2,3-di(2-mercaptoethylthio)-1-propane-thiol, dimercaptodiethylsulfide (2,2′-thiodiethanethiol), dimercaptodioxaoctane (2,2′-(ethylenedioxy)diethanethiol, 1,8-dimercapto-3,6-dioxaoctane, and combinations of any of the foregoing.

[0033] Suitable thiol-containing monomers for use in compositions disclosed herein are commercially available, for example, from Bruno Bock Thiochemicals under the Thiocure® tradename. Suitable thiol-containing polymers for use in compositions disclosed herein are commercially available, for example, from Toray Industries, Inc. under the Thiokol® LP tradename or from Nouryon under the Thioplast® tradename. Such polysulfide polymers are disclosed in U.S. Patent No. 2,466,963, col. 2, ln. 13 to col. 31, ln. 68 the cited portions of which are incorporated herein by reference.

[0034] The thiol-containing compound may have a weight average molecular weight (Mw) of at least 80 g / mol, such as at least 150 g / mol, and may have a Mw of no more than 40,000 g / mol, such as no more than 20,000 g / mol. The thiol-containing compound may have a Mw of 80 g / mol to 40,000 g / mol, such as 100 g / mol to 40,000 g / mol, such as 150 g / mol to 20,000 g / mol. Mw may be measured by gel permeation chromatography using polystyrene standards for calibration.

[0035] The composition may comprise the thiol-containing compound in an amount of at least 10 percent by weight based on total weight of the composition, such as at least 17 percent by weight. The composition may comprise the thiol-containing compound in an amount of no more than 88.5 percent by weight based on total weight of the composition, such as no more than 47 percent by weight. The composition may comprise the thiol-containing compound in anamount of 10 percent by weight to 88.5 percent by weight based on total weight of the composition, such as 17 percent by weight to 47 percent by weight. Oxidants

[0036] The composition may comprise an oxidant. The oxidant may polymerize the thiol-containing compound to rubbery solids by reducing the thiol functional group of the thiol- containing compound to form sulfur-sulfur bonds. For example, a mechanism of cure may comprise 2 -RSH + (O) ^RSSR + H2O.

[0037] Suitable oxidants that may be used in the compositions may comprise a metal oxide and / or an organic peroxide. For example, the oxidant may comprise a metal oxide such as zinc oxide, lead oxide, lead dioxide, lead peroxide, manganese dioxide, sodium dichromate, sodium perborate, sodium perborate monohydrate, potassium permanganate, calcium dioxide, calcium peroxide, barium peroxide, lithium peroxide, zinc peroxide, zinc chromate, barium oxide, alkaline dichromate, or combinations thereof. The oxidant may comprise an organic peroxide such as cumene hydroperoxide, t-butyl hydroperoxide, or combinations thereof.

[0038] The composition may comprise the oxidant in an amount of at least 1 percent by weight based on total weight of the composition, such as at least 2 percent by weight. The composition may comprise the oxidant in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 7 percent by weight. The composition may comprise the oxidant in an amount of 1 percent by weight to 10 percent by weight based on total weight of the composition, such as 2 percent by weight to 7 percent by weight. Thermally Expandable Material

[0039] The composition of the present disclosure may further comprise a thermally expandable material. The thermally expandable material may be present in the first component, the second component, and / or a third component. As used herein, the term “thermally expandable” means a pigment, filler, encapsulant, thermoplastic, inorganic powder, capsule, microcapsule, or the like that, upon heating, undergoes an increase in volume in at least one dimension.

[0040] Suitable examples of thermally expandable material may comprise inorganic salts and / or thermally expandable graphite, such as thermally expandable graphite available from ACS Material.

[0041] The thermally expandable material may comprise thermally expandable capsules. The thermally expandable capsules may comprise thermally expandable hollow capsules. The thermally expandable capsules may comprise a thermoplastic resin and / or a volatile material such as a volatile hydrocarbon and / or a volatile gas. The thermally expandable capsules may comprise a thermoplastic resin shell with a volatile material core. Suitable thermally expandable materials comprise Expancel available from Nouryon, Advancell available from Sekisui, and the like.

[0042] The thermally expandable material may have an average initial (i.e., pre- expansion) particle size of at least 0.5 µm, such as at least 1 µm, such as at least 2 µm, such as at least 3 µm, such as at least 5 µm, such as at least 10 µm. The thermally expandable material may have an average initial particle size of no more than 100 µm, such as no more than 80 µm, such as no more than 60 µm, such as no more than 50 µm. The thermally expandable material may have an average initial particle size of 0.5 µm to 100 µm, such as 1 µm to 80 µm, such as 2 µm to 60 µm, such as 3 µm to 50 µm, such as 5 µm to 50 µm, such as 10 µm to 50 µm. Initial particle size of the thermally expandable material may be measured by methods known to those skilled in the art, such as laser diffraction or Low Angle Laser Light Scattering (LALLS).

[0043] The thermally expandable material may have an expansion temperature of at least 60°C, such as at least 70°C, such as at least 80°C, such as at least 90°C, such as at least 100°C, such as at least 110°C, such as at least 120°C, such as at least 130°C, such as at least 140°C, such as at least 150°C, such as at least 160°C, such as at least 170°C, such as at least 180°C, such as at least 190°C, such as at least 200°C, such as no more than 250°C. As used herein, the term “expansion temperature,” when used with respect to the thermally expandable material, means the temperature at which the particle size begins to increase due to an increase in volume in at least one dimension. In the case of thermally expandable capsules, the increase in particle size may be, for example, the result of the volatile material beginning to expand while the thermoplastic resin shell softens. Expansion temperature may be achieved, for example, by heating the coating comprising the thermally expandable material and / or heating the substrate on which the coating is formed. The coating and / or the substrate may be heated by direct thermal exposure and / or, in substrates containing ferromagnetic materials, superparamagnetic materials, and / or ferrimagnetic materials or in coatings formed from compositions containing ferromagnetic materials, superparamagnetic materials and / or ferrimagnetic materials, by indirectheating through the application of a magnetic field resulting in ferromagnetic heating, superparamagnetic heating, or ferrimagnetic heating.

[0044] The composition may comprise the thermally expandable material in an amount of at least 0.5 percent by weight based on total weight of the composition, such as at least 1 percent by weight. The composition may comprise the thermally expandable material in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 3 percent by weight. The composition may comprise the thermally expandable material in an amount of 0.5 percent to 10 percent by weight based on total weight of the composition, such as 1 percent by weight to 3 percent by weight. Filler

[0045] The composition comprises a filler. Useful fillers that may be included in the composition include cellulose, starch, acrylics, fiberglass, fibrous titanium dioxide, whisker type calcium carbonate (aragonite), carbon fiber (which includes graphite and carbon nanotubes), borosilicate, aluminosilicate, calcium carbonate, and the like. The filler may be a thermally conductive filler such as, for example, boron nitride, aluminum trihydrate, metal oxide, metal hydroxide, graphite, graphene, and the like. The filler may be a non-thermally conductive filler, such as, for example, mica, wollastonite, calcium carbonate, glass microspheres, clay, silicon dioxide, and the like.

[0046] The filler may comprise a thermally conductive, electrically insulative filler (referred to herein as “TC / EI filler” and described in more detail below) and / or a thermally conductive, electrically conductive filler (referred to herein as “TC / EC filler” and described in more detail below). The TC / EI and / or TC / EC filler (referred to collectively as “thermally conductive filler”) may be present in the first component, the second component and / or a third component. The thermally conductive filler may comprise an organic or inorganic material and may comprise particles of a single type of filler material or may comprise particles of two or more types of TC / EI filler and / or two or more types of TC / EC filler. That is, the filler may comprise a first TC / EI filler and may further comprise at least a second (i.e., a second, a third, a fourth, etc.) TC / EI filler in addition to the first TC / EI filler. Likewise, the filler may comprise a first TC / EC filler and may further comprise at least a second (i.e., a second, a third, a fourth, etc.) TC / EC filler in addition to the first TC / EC filler. As used herein with respect to types of filler,reference to “first,” “second”, etc. is for convenience only and does not refer to order of addition to the composition or the like.

[0047] The composition may comprise the thermally conductive filler material in an amount of 100 percent by volume based on total volume of filler. The composition may comprise the thermally conductive filler material in an amount of no more than 90 percent by volume, such as no more than 80 percent by volume. The composition may comprise the thermally conductive filler material in an amount of at least 20 percent by volume based on total volume of filler, such as at least 50 percent by volume. The composition may comprise the thermally conductive filler material in an amount of 20 percent to 90 percent by volume based on total volume of filler, such as 50 percent by volume to 80 percent by volume.

[0048] The filler may comprise a non-thermally conductive filler. That is, the compositions disclosed herein may comprise a non-thermally conductive, electrically insulative filler (referred to herein as a “NTC / EI” filler). The NTC / EI filler may be present in the first component, the second component and / or a third component. The NTC / EI filler may comprise an organic or inorganic material and may comprise particles of a single type of filler material or may comprise particles of two or more types of NTC / EI filler. That is, the composition may comprise a first NTC / EI filler and may further comprise at least a second (i.e., a second, a third, a fourth, etc.) NTC / EI filler in addition to the first NTC / EI filler.

[0049] The composition may comprise the NTC / EI filler in an amount of at least 10 percent by volume based on total volume of filler, such as at least 20 percent by volume. The composition may comprise the NTC / EI filler in an amount of no more than 80 percent by volume based on total volume of filler, such as no more than 50. The composition may comprise the NTC / EI filler in an amount of 10 percent by volume to 80 percent by volume based on total volume of filler, such as 20 percent by volume to 50 percent by volume.

[0050] Optionally, the filler may comprise a surface coating. The surface coating may comprise a silane, an amino-silane and / or a multidentate polymer.

[0051] The filler may have a reported average particle size in at least one dimension of at least 0.01 µm, such as at least 2 µm, such as at least 10 µm, and may have a reported average particle size in at least one dimension of no more than 500 µm as reported by the manufacturer, such as no more than 400 µm, such as no more than 300 µm, such as no more than 100 µm. The filler may have an average particle size in at least one dimension of 0.01 µm to 500 µm, such as0.1 µm to 400 µm, such as 2 µm to 300 µm, such as 10 µm to 100 µm. Particle sizes may be measured by methods known to those skilled in the art, for example, using a scanning electron microscope (SEM), such as a Quanta 250 FEG SEM or an equivalent instrument. For example, powders may be dispersed on segments of carbon tape attached to aluminum stubs and coated with Au / Pd for 20 seconds. Samples then may be analyzed in an SEM under high vacuum (accelerating voltage 10kV and spot size 3.0), measuring 30 particles from three different areas to provide an average particle size for each sample. One skilled in the art will recognize that there can be variations in this procedure that retain the essential elements of microscopic imaging and averaging of representative size. Alternatively, particle sizes may be reported by the manufacturer.

[0052] The thermally conductive filler may comprise particles each having, for example, a platy, spherical, acicular shape, or irregular shape and agglomerates thereof. As used herein, “platy” refers to a two-dimensional material having a substantially flat surface and that has a thickness in one direction that is less than 25% of the largest dimension.

[0053] The thermally conductive filler may have a thermal conductivity of at least 5 W / m∙K at 25oC (measured according to ASTM D7984-21), such as at least 18 W / m∙K, such as at least 55 W / m∙K, and may have a thermal conductivity of no more than 3,000 W / m∙K at 25oC, such as no more than 1,400 W / m∙K, such as no more than 450 W / m∙K. The thermally conductive filler may have a thermal conductivity of 5 W / m∙K to 3,000 W / m∙K at 25oC, such as 18 W / m∙K to 1,400 W / m∙K, such as 55 W / m∙K to 450 W / m∙K.

[0054] The NTC / EI filler may have a thermal conductivity of less than 5 W / m∙K at 25oC (measured according to ASTM D7984-21), such no more than 3 W / m∙K, such as no more than 1 W / m∙K, such as no more than 0.1 W / m∙K, such as no more than 0.05 W / m∙K, such as 0.02 W / m∙K at 25oC to 5 W / m∙K at 25oC.

[0055] The filler (TC / EI and / or NTC / EI) may be electrically insulative. The electrically insulative filler may have a volume resistivity of at least 1 Ω.m, such as at least 10 Ω.m, such as at least 100 Ω.m. Electrical insulation may be measured according to ASTM D257-19.

[0056] The TC filler may be electrically conductive. The TC / EC filler may have a volume resistivity of less than 1 Ω.m, such as less than 0.1 Ω.m. Electrical conductivity may be measured according to ASTM D257-19.

[0057] Suitable TC / EI fillers include boron nitride (for example, commercially available as CarboTherm from Saint-Gobain, as CoolFlow and PolarTherm from Momentive, and as hexagonal boron nitride powder available from Panadyne), silicon nitride, or aluminum nitride (for example, commercially available as aluminum nitride powder available from Micron Metals Inc., and as Toyalnite from Toyal), metal oxides such as Boehmite, Pseudo Boehmite, aluminum oxide (for example, commercially available as Microgrit from Micro Abrasives, as Nabalox from Nabaltec, as Martoxid from Huber, as Aeroxide from Evonik, and as Alodur from Imerys), magnesium oxide, beryllium oxide, titanium oxide, zinc oxide, nickel oxide, copper oxide, or tin oxide, metal hydroxides such as aluminum hydroxide or magnesium hydroxide, arsenides such as boron arsenide, carbides such as silicon carbide, minerals such as agate and emery, ceramics such as ceramic microspheres (for example, commercially available from Zeeospheres Ceramics or 3M), silicon carbide, and diamond. The filler can also be surface modified, such as PYROKISUMA 5301K available from Kyowa Chemical Industry Co., Ltd. The thermally conductive filler may be used alone or in a combination of two or more. The TC / EI filler may also be ferromagnetic, ferrimagnetic, and / or superparamagnetic.

[0058] Suitable TC / EC fillers include metals such as silver, zinc, copper, gold, or metal coated hollow particles, carbon compounds such as graphite (such as Timrex commercially available from Imerys or ThermoCarb commercially available from Asbury Carbons), carbon black (such as Vulcan commercially available from Cabot Corporation), carbon fibers (for example, commercially available as milled carbon fiber from Zoltek), graphene and graphenic carbon particles (for example, xGnP graphene nanoplatelets commercially available from XG Sciences, and / or for example, the graphenic carbon particles described below), carbonyl iron, copper (such as spheroidal powder commercially available from Sigma Aldrich), zinc (such as Ultrapure commercially available from Purity Zinc Metals and Zinc Dust XL and XLP available from US Zinc), and the like. Examples of “graphenic carbon particles” include carbon particles having structures comprising one or more layers of one-atom-thick planar sheets of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice. The average number of stacked layers may be less than 100, for example, less than 50. The average number of stacked layers may be 30 or less, such as 20 or less, such as 10 or less, such as 5 or less. The graphenic carbon particles may be substantially flat; however, at least a portion of the planar sheets may be substantially curved, curled, creased, or buckled. The particles typically do not have a spheroidalor equiaxed morphology. Suitable graphenic carbon particles are described in U.S. Publication No. 2012 / 0129980, at paragraphs

[0059] -

[0065] , the cited portion of which is incorporated herein by reference. Other suitable graphenic carbon particles are described in U.S. Patent No. 9,562,175, at 6:6 to 9:52, the cited portion of which is incorporated herein by reference. As used herein, the term “substantially flat” means planar; “curved” or “curled” materials deviate from planarity by having a non-zero curvature; and “creased” or “buckled” indicates that at least a portion of the area is thicker than one sheet, such that the plane is doubled or folded upon itself. The TC / EC filler may also be ferromagnetic, ferrimagnetic, and / or superparamagnetic.

[0059] Suitable NTC / EI fillers include but are not limited to mica, wollastonite, calcium carbonate, glass microspheres, clay, silicon dioxide, or combinations thereof.

[0060] As used herein, the term “mica” generally refers to sheet silicate (phyllosilicate) minerals. The mica may comprise muscovite mica. Muscovite mica comprises a phyllosilicate mineral of aluminum and potassium with the formula KAl2(AlSi3O10)(F,OH)2or (KF)2(Al2O3)3(SiO2)6(H2O). Exemplary non-limiting commercially available muscovite mica include products sold under the trade name DakotaPURE™, such as DakotaPURE™ 700, DakotaPURE™ 1500, DakotaPURE™ 2400, DakotaPURE™ 3000, DakotaPURE™ 3500 and DakotaPURE™ 4000, available from Pacer Minerals. Wollastonite comprises a calcium inosilicate mineral (CaSiO3) that may contain small amounts of iron, aluminum, magnesium, manganese, titanium and / or potassium. The wollastonite may have a B.E.T. surface area of 1.5 to 2.1 m2 / g, such as 1.8 m2 / g and a median particle size of 6 microns to 10 microns, such as 8 microns. Non-limiting examples of commercially available wollastonite include NYAD 400 available from NYCO Minerals, Inc.

[0061] The calcium carbonate (CaCO3) may comprise a precipitated calcium carbonate or a ground calcium carbonate. The calcium carbonate may or may not be surface treated, such as treated with stearic acid, such as Socal® 312, commercially available from IMERYS. Non- limiting examples of commercially available precipitated calcium carbonate include Ultra- Pflex®, Albafil®, and Albacar HO® available from Specialty Minerals and Winnofil® SPT available from Solvay. Non-limiting examples of commercially available ground calcium carbonate include DuramiteTMavailable from IMERYS and Marblewhite® available from Specialty Minerals.

[0062] Useful clay minerals include a non-ionic platy filler such as talc, pyrophyllite, chlorite, vermiculite, or combinations thereof.

[0063] The glass microspheres may be hollow borosilicate glass. Non-limiting examples of commercially available glass microspheres include 3M Glass bubbles type VS, K series, and S series available from 3M.

[0064] The filler may comprise a thermally stable filler and / or a thermally unstable filler.

[0065] The compositions disclosed herein may comprise a filler in an amount of at least 1 percent by weight based on total weight of the composition, such as at least 5 percent by weight. The compositions disclosed herein may comprise a filler in an amount of no more than 80 percent by weight based on total weight of the composition, such as no more than 75 percent by weight. The compositions disclosed herein may comprise a filler in an amount of 1 percent by weight to 80 percent by weight based on total weight of the composition, such as 5 percent by weight to 75 percent by weight.

[0066] The compositions disclosed herein may comprise TC filler in an amount of at least 10 percent by weight based on total weight of the composition, such as at least 50 percent by weight. The compositions disclosed herein may comprise TC filler in an amount of no more than 88.5 percent by weight based on total weight of the composition, such as no more than 80 percent by weight. The compositions disclosed herein may comprise TC filler in an amount of 10 percent to 88.5 by weight based on total weight of the composition, such as 50 percent to 80 percent by weight. Cure Additives

[0067] The composition may further comprise a cure additive, such as a cure retarder or an accelerator, in order to modify the curing rate of the composition. As used herein, “cure retarder” refers to a substance that decreases the rate or increases the activation energy of a chemical reaction in comparison to the same reaction in the absence of a cure retarder. As used herein, “accelerator” refers to a substance that increases the rate or decreases the activation energy of a chemical reaction in comparison to the same reaction in the absence of an accelerator. An accelerator may be either a “catalyst” (that is, without itself undergoing any permanent chemical change), or may be reactive (that is, undergoing a permanent chemical change).

[0068] The composition optionally may comprise a polysulfide cure retarder or a combination of polysulfide cure retarders. A polysulfide cure retarder can comprise an acid such as a fatty acid, an organic acid, an inorganic acid, a fatty acid salt, or combinations thereof. Examples of suitable polysulfide cure retarders include phenylphosphonic acid and itaconic acid. Cure retarders can improve the stability of the polysulfide cure activator and polysulfide cure accelerator.

[0069] Suitable accelerators include, for example, thiazoles, thiurams, sulfenamides, guanidines, dithiocarbamates, xanthates, thioureas, aldehydeamines, and combinations of any of the foregoing. Examples of suitable thiazoles include bis(2-benzothiazole) disulfide (MBTS), 2- mercaptobenzothiazole (MBT), and the zinc salt of mercaptobenzothiazole (ZMBT). Examples of suitable thiurams include tetramethyl thiuram monosulfide, tetramethyl thiuram disulfide (TMTD), tetraethyl thiuram disulfide, tetrabutyl thiuram disulfide, dipentamethylene thiuram hexasulfide, dicyclohexamethylene thiuram disulfide, diisopropyl thiuram disulfide, bis(morpholinothiocarbonyl) sulfide, tetramethyl thiuram monosulfide (TMTM), dipentamethylene thiuram tetrasulfide (DPTT), and compounds having the structure (R)2N– C(=S)–Sx–C(=S)–N(R)2 where each R can be C1-6 alkyl and x is an integer from 1 to 4, and combinations of any of the foregoing. Examples of suitable sulfonamides include N-cyclohexyl- 2-benzothiazolsulfenamide, tertbutyl-2-benzothiazolsulfenamide (TBBS), dicyclohexyl-2- benzothiazolsulfenamide (DCBS), and combinations of any of the foregoing. Examples of suitable guanidines include diphenyl guanidine (DPG), N,N’-diorthotolyl guanidine (DOTG), compounds having the structure R–NH–C(=NH)–NH–R where each R is selected from C1-6 alkyl, phenyl and toluoyl, and combinations of any of the foregoing. Examples of suitable dithiocarbamates include zinc dialkyl dithiocarbamates such as dimethyl- dithiocarbamate (ZDMC), diethyl-dithiocarbamate (ZDEC) and dibutyl-dithiocarbamate (ZDBC), other metal or ammonium salts of dithiocarbamoic acid, compounds having the structure Zn(–S–C(=S)–N(R)2) where each R is selected from C1-6 alkyl, phenyl and toluoyl, and combinations of any of the foregoing. Examples of suitable xanthates include zinc salts of xanthic acid. Examples of suitable thioureas include ethylene thiourea (ETU), dipentamethylene thiourea (DPTU), dibutyl thiourea (DBTU), and compounds having the structure R–NH–C(=S)–NH–R where each R is selected from C1-6alkyl, phenyl and toluoyl, and combinations of any of the foregoing. Examples of suitable aldehydeamines include condensation products of aldehydes and amines,such as aniline, ammoniac or their derivatives and also butyraldehyde, crotonylaldehyde or formaldehyde such as butyraldehydeaniline and tricrotonylidenetetramine, and combinations of any of the foregoing. Examples of other suitable cure accelerators include triazines and sulfides or metallic and amine salts of dialkyldithiophosphoric acids and dithiophosphates such as triazines and sulfides or metallic and amine salts of dialkyldithiophosphoric acids, and combinations of any of the foregoing. Examples of non-sulfur-containing polysulfide cure accelerators include tetramethyl guanidine (TMG), di-o-tolyl guanidine (DOTG), sodium hydroxide (NaOH), water, and bases such as amines. Examples of amines include quaternary amines, tertiary amines, cyclic tertiary amines, or secondary amines.

[0070] The compositions disclosed herein may comprise the cure additive in an amount of at least 0.05 percent by weight based on total weight of the composition, such as at least 0.1 percent by weight. The compositions disclosed herein may comprise the cure additive in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 5 percent by weight. The compositions disclosed herein may comprise the cure additive in an amount of 0.05 percent by weight to 10 percent by weight based on total weight of the composition, such as 0.1 percent by weight to 5 percent by weight. Additives

[0071] The composition may optionally comprise an additive. As used herein, an “additive” refers to a rheology modifier, a dispersing agent, a tackifier, a thermoplastic polymer, a surfactant, a flame retardant, a corrosion inhibitor, a UV stabilizer, a colorant, a tint, an adhesion promoter, a moisture scavenger, a solvent, a plasticizer, an adhesion promoter, and the like. Certain thermally conductive materials such as aluminum hydroxide and magnesium hydroxide, for example, also may be flame retardants; for purposes of calculating weight percentages herein, such materials are counted as thermally conductive materials. As used herein, “flame retardant” refers to a material that slows down or stops the spread of fire or reduces its intensity. Flame retardants may be available as a powder that may be mixed with a composition, a foam, or a gel. In examples, when the compositions disclosed herein include a flame retardant, such compositions may form a coating on a substrate surface and such coating may function as a flame retardant. A flame retardant can include a mineral, an organic compound, an organohalogen compound, an organophosphorous compound, or a combination thereof.

[0072] The composition may comprise the additive in an amount of at least 0.5 percent by weight based on total weight of the composition, such as at least 1 percent by weight. The composition may comprise the additive in an amount of no more than 20 percent by weight based on total weight of the composition, such as no more than 17 percent by weight. The composition may comprise the additive in an amount of 0.5 percent by weight to 20 percent by weight based on total weight of the composition, such as 1 percent by weight to 17 percent by weight. Compositions, Systems, and Methods

[0073] The compositions disclosed herein may be formulated as a 1K composition comprising, or consisting essentially of, or consisting of: a thiol-containing compound; an oxidant; a thermally expandable material; and a thermally conductive filler.

[0074] The compositions disclosed herein may be formulated as a 2K composition comprising, or consisting essentially of, or consisting of: a first component comprising, or consisting essentially of, or consisting of, a thiol-containing compound; a second component comprising, or consisting essentially of, or consisting of, an oxidant; a thermally expandable material; and a thermally conductive filler. The thermally expandable material and / or the thermally conductive filler each may be present in the first component, the second component, and / or a third component. The first and second components may be mixed together immediately prior to use.

[0075] The compositions of a two-component composition may be mixed and provided as pre-mixed frozen compositions (PMF). PMFs may be packaged, for example, in a cartridge, a cartridge and plunger, a syringe, or may be supplied as a tape, a cap, or any preformed geometry. PMFs may be cured by external factors, such as temperature. In examples, the PMF may be stored at temperatures of -100°C to -15°C, such as -100oC to -25oC, such as -100oC to -40oC, such as -75oC to -15oC, such as -75oC to -25oC, such as -75oC to -40oC, to inhibit curing. When applying the composition to the substrate, the composition may be cured by (i) exposing the composition to temperatures sufficient to initiate cure of the composition, provided that such temperatures are below the expansion temperature of the thermally expandable material, and / or (ii) oxidation. As used herein, the term “inhibiting,” when used with respect to curing, refers to restraining, impeding, slowing or interfering with a particular reaction or function. This can be accomplished in a number of ways, for example, controlling the environment to which thecomposition is exposed, such as limiting the composition’s exposure to ambient conditions and / or by restraining, impeding, slowing or interfering with the oxidation of the thiol-containing compound. In a non-limiting example, oxidation may be inhibited by limiting the composition’s exposure to air or ambient conditions.

[0076] Under thermal conditions of at least the expansion temperature of the thermally expandable material, the thermally expandable material may have an expansion volume ratio (i.e., post-expansion volume / pre-expansion volume) of at least 5 such as at least 10, such as at least 20, such as at least 25, such as at least 50, such as at least 75, such as at least 100, such as at least 125, such as at least 175, such as at least 200. Under thermal conditions of at least the expansion temperature of the thermally expandable material, the thermally expandable material may have an expansion volume ratio (i.e., post-expansion volume / pre-expansion volume) of no more than 250. Under thermal conditions of at least the expansion temperature of the thermally expandable material, the thermally expandable material may have an expansion volume ratio (i.e., post-expansion volume / pre-expansion volume) of 5 to 250, such as 10 to 250, such as 20 to 250, such as 25 to 250, such as 50 to 250, such as 75 to 250, such as 100 to 250, such as 125 to 250, such as 175 to 250, such as 200 to 250. The post-expansion volume and the pre-expansion volume of the thermally expandable material may be measured by methods known to those skilled in the art, such as SEM, laser diffraction, or LALLS. Methods

[0077] Also disclosed herein are methods for preparing the compositions disclosed above. In the case of a 2K composition, the method optionally may comprise mixing a thiol- containing compound with a thermally expandable material and / or a thermally conductive filler to form the first component. The oxidant may be mixed with a thermally expandable material and / or a thermally conductive filler to form the second component. The first component and the second component and optionally a third component may be mixed to form the compositions disclosed above. Such mixing may be at a temperature of less than 50°C, such as from 0°C to 50°C, such as from 15°C to 35°C, such as at ambient temperature, provided that such temperature is below the expansion temperature of the thermally expandable material.

[0078] The method may comprise curing the composition at a temperature lower than the expansion temperature of the expandable material and / or curing the coating prior to expansion.

[0079] The compositions described above may be applied alone or as part of a system that can be deposited in different ways onto different substrates. Accordingly, disclosed herein are methods for treating a substrate comprising, or consisting essentially of, or consisting of, contacting a surface of the substrate with any of the compositions disclosed herein. “Contacting a surface of the substrate” encompasses contacting a surface of a substrate that has been treated with other coatings, as described herein. Optionally, the method may comprise mixing the first component and the second component to form the composition. The composition can be applied to the surface of a substrate in different ways, non-limiting examples of which include brushing, rolling, via film, via pellets, troweling, via spatulas, dipping, via spray guns, and via applicator guns to form a coating on the substrate surface.

[0080] After application to the substrate(s), the composition may be cured to form a thermally expandable coating prior to expansion of the thermally expandable material. For example, the composition may be allowed to cure at room temperature or slightly thermal conditions, and for any desired time (e.g., 2 weeks under ambient conditions) sufficient to cure the composition on the substrate(s) and / or the composition may be cured by baking and / or curing under thermal conditions, provided that the thermal conditions are lower than the expansion temperature of the thermally expandable material, such as at a temperature of 180˚C or below, such as 130˚C or below, such as 110˚C or below, such as 100˚C or below, such as 90˚C or below, such as 80˚C or below, such as 70˚C or below, but greater than ambient, such as greater than 40˚C, such as greater than 50˚C, and for any desired time (e.g., from 5 minutes to 24 hours) sufficient to at begin curing the composition on the substrate(s). In the case of PMF, the composition may be cured by thawing. Upon cure, the composition may form a coating on the substrate surface. The coating may be, for example, an adhesive, a structural adhesive, a pottant, a pre-preg, a liquid shim, a sealant, or a gap filler. The composition may be cured to form an article, such as by additive manufacturing, such as three-dimensional (“3D”) printing as described below.

[0081] The method optionally may further comprise contacting a surface of a second substrate to the composition such that the composition is between the first substrate and the second substrate. For example, the composition may be applied to either one or both of the first and second substrates such that the composition is positioned between the first and the secondsubstrates. In examples, the substrates may be aligned, and pressure and / or spacers may be added to control bond thickness.

[0082] The composition may be applied to cleaned or uncleaned (i.e., including oil or oiled) substrate surfaces. The compositions disclosed herein may also be applied to a substrate that has been pretreated, coated with an electrodepositable coating, and / or coated with additional coatings such as a primer, basecoat, or topcoat.

[0083] Thermally expandable coatings disclosed herein may have a pre-expansion thermal conductivity of at least 0.5 W / m∙K at 25oC measured according to ASTM D7984-21 using a modified transient plane source instrument, such as at least 1 W / m∙K, such as at least 2 W / m.K, such as at least 3 W / m∙K, such as at least 4 W / m∙K, such as at least 5 W / m∙K.

[0084] Thermally expandable coatings disclosed herein may have a decrease in thermal conductivity post-expansion (following exposure to at least the expansion temperature of the thermally expandable material) relative to pre-expansion thermal conductivity (measured at 25oC according to ASTM D7984-21 using a modified transient plane source instrument) of at least 10%, such as at least 25%, such as at least 50%, such as at least 75%, such as at least 95%, such as at least 96%, such as at least 97%, such as at least 98%, such as at least 99%.

[0085] Following exposure to thermal conditions (e.g., at least the expansion temperature of the thermally expandable material), the thermally expandable material may have an expansion volume ratio (i.e., post-expansion volume / pre-expansion volume) of greater than 1 when measured at 25oC and by methods known to those skilled in the art, such as SEM, laser diffraction, or LALLS, such as at least 1.1, such as at least 1.2, such as at least 1.5, such as at least 2, such as at least 2.5, such as at least 3, such as at least 4, such as at least 5, such as at least 10, such as at least 20, such as at least 50, such as at least 75, such as at least 100, such as at least 125, such as at least 175, such as at least 200.

[0086] The thermally expandable coatings disclosed herein may have a post-expansion volume ratio of greater than 1, such as at least 1.1, such as at least 1.2, such as at least 1.5, such as at least 2, such as at least 3, such as at least 5, such as at least 10, such as at least 20, wherein the post-expansion volume ratio = post-expansion volume (measured at 25°C following exposure to at least the expansion temperature of the thermally expandable material) / pre-expansion volume (measured at 25°C prior to exposure to at least the expansion temperature of thethermally expandable material) and wherein volumes are measured using a caliper and the coating is cohesive / non-crumbling.

[0087] When the disclosed compositions are highly loaded compositions (i.e., contained thermally conductive filler in an amount of 50 percent by weight up to 90 percent by weight based on total weight of the composition in combination with thermally expandable material in an amount of at least 0.5 percent by weight based on total weight of the composition, such as less than 10 percent by weight), the compositions were found to be pumpable (i.e., each component having a viscosity of no more than 106Pa.s at a shear stress of 1 Hz measured by an Anton Paar MCR 301 rotational rheometer at 25oC using a parallel plate with a diameter of 25 mm (1 mm gap)). This was a surprising result.

[0088] The coatings also have a pre-expansion tensile stress of at least 0.5 MPa measured according to ASTM D412-16(2021), such as at least 0.6 MPa, such as at least 0.7 MPa and a pre- expansion tensile strain of at least 5% measured according to ASTM D412-16(2021), such as at least 6%. These results were surprising for such a highly loaded system (i.e., containing thermally conductive filler in an amount of 50 percent by weight up to 90 percent by weight based on total weight of the composition in combination with thermally expandable material in an amount of at least 0.5 percent by weight based on total weight of the composition).

[0089] The combination of properties described above was surprising and unexpected.

[0090] Articles may be formed from one of the compositions disclosed herein and cured under ambient conditions or by exposure to an external energy source as described above. The articles may be formed through extrusion, casting, molding, additive manufacturing, such as 3D- printing, subtractive manufacturing, and / or machining. Dielectric Coating Compositions and Dielectric Coatings and Dielectric Systems and Kits

[0091] Any of the substrates disclosed herein may comprise a dielectric coating in addition to the thermally expandable coating. The dielectric coating composition and the thermally expandable coating composition may form continuous or discontinuous coatings, provided that the coatings overlap to form a coating stack, e.g., a thermally expandable coating formed from the thermally expandable coating composition on a dielectric coating formed from the dielectric coating composition. Such a coating stack does not preclude the possibility of coatings in addition to the dielectric coating and the second coating, wherein such additional coatings may or may not be positioned between the dielectric coating and the second coating.Optionally, the coating stack may be formed between two substrates. As used herein, “dielectric” refers to a coating composition or coating comprising a dielectric strength of at least 10 kV / mm measured using a Sefelec Dielectric Strength Tester (RMG12AC-DC; voltage limit 12.0 kV, Imax Limit 0.1 mA, 19 sec ramp, 20 sec dwell, 2 sec fall) according to ASTM D149- 09, such as at least 12 kV / mm, such as at least 15 kV / mm.

[0092] Also disclosed herein are coating systems. The coating system may comprise: a dielectric coating composition for application to a first portion of a substrate surface; and any of the thermally expandable coating compositions disclosed herein for application to a second portion of a substrate surface. In a cured state, the dielectric coating composition may form a dielectric coating. In a cured state, the thermally expandable coating composition may form a thermally expandable coating.

[0093] Also disclosed herein are coating kits. The coating kit may comprise: a dielectric coating composition for application to a first portion of a substrate surface; and any of the thermally expandable coating compositions disclosed herein for application to a second portion of the substrate surface. The kit optionally may comprise instructions for applying the dielectric coating composition and the thermally expandable coating composition to the substrate surface.

[0094] As used herein with respect to dielectric coatings and thermally expandable coatings, and systems and kits comprising compositions for forming the same, the first portion and the second portion may be on a single substrate or may be on a first substrate and a second substrate, respectively.

[0095] The dielectric coating composition may comprise a binder comprising a film- forming resin. As used herein, a “film-forming resin” refers to one or more monomers, oligomers, prepolymers and / or polymers, such as homopolymers and / or copolymers, that can form a coating upon reaction with a curing agent or crosslinker, upon evaporation of a solvent, and / or upon photo or thermal activation. The dielectric coating composition may comprise any suitable film-forming resin, including organic film-forming resins and / or inorganic film-forming resins, such as silicon-based film-forming resins. Examples of suitable film-forming resins include but are not limited to polyester, alkyd, urethane, isocyanate, polyurea, epoxy, acrylic, polyether, polysulfide, polyamine, polyamide, polyvinyl chloride, polyolefin, polyvinylidene fluoride, polyvinyl chloride, polyolefin, polysiloxane, amine-aldehydes, resinous polyols,phosphatized polyepoxides, phosphatized acrylic polymers, aminoplasts, or combinations thereof.

[0096] The dielectric coating composition may optionally comprise a curing agent and / or a crosslinker that is capable of crosslinking with the film-forming resin to cure the dielectric coating composition. Any suitable curing agent and / or crosslinker that is capable of crosslinking with the film-forming resin may be used. Examples of suitable curing agents include but are not limited to amines, aminoplasts, phenoplasts, polyisocyanates, including blocked isocyanates, polyepoxides, beta-hydroxyalkylamides, polyacids, organometallic acid-functional materials, polyamines, polyamides, polysulfides, polythiols, polyenes such as polyacrylates, polyols, polysilanes and the like, or combinations thereof.

[0097] The dielectric coating composition may optionally further comprise a colorant, a pigment, an additive, and / or a filler. Suitable fillers that may be used in the dielectric coating composition include a TC / EI filler, a TC / EC filler, and / or a NTC / EI filler.

[0098] The dielectric coating composition may comprise a thermoset coating composition, wherein the coating composition is cured upon crosslinking of a film-forming resin and a curing agent and / or crosslinker. Alternatively, the dielectric coating composition may comprise a thermoplastic coating composition, wherein the coating composition comprises a film-forming resin that cures upon evaporation of water and / or solvent. Alternatively, the dielectric coating composition may comprise a thermoset or thermoplastic coating composition that cures upon exposure to actinic radiation, such as ultraviolet light.

[0099] The dielectric coating composition may comprise a liquid coating composition or a powder coating composition. As used herein, when referring to a dielectric coating composition, “liquid” means a material having a viscosity less than 100,000 Pa∙s at 25°C as measured by parallel plate rheology with a plate diameter of 25 mm, a gap of 0.5 mm, and a shear rate of 1 s-1.

[0100] Suitable liquid coating compositions include but are not limited to electrodepositable coating compositions, one-component coating compositions, and / or multi- component coating compositions.

[0101] For example, the liquid dielectric coating composition may comprise an electrodepositable coating composition. The electrodepositable coating composition may comprise one or more cationic or anionic salt group-containing film-forming resins that may bedeposited onto a metal or other conductive substrate under the influence of an applied electrical potential, i.e., by electrodeposition.

[0102] In other examples, the liquid dielectric coating composition may comprise a UV- curable coating composition comprising film-forming resins capable of curing upon exposure to UV radiation. Any suitable UV-curable film-forming resin may be used, such as free radical polymerizable resins containing ethylenic unsaturation or olefinic double bonds and / or film- forming resins that may react through a cationic photopolymerization mechanism. Examples of suitable UV-curable coating compositions that may be used include but are not limited to the RAYCRON line of UV-curable coatings, commercially available from PPG Industries, Inc.

[0103] Other suitable liquid dielectric coating compositions include but are not limited to the SPECTRACRON line of solvent-based coating compositions and the AQUACRON line of water-based coating compositions, all commercially available from PPG Industries, Inc. The liquid dielectric coating may also be applied as a two-component composition where the film- forming resins and the reactive curing agent and / or crosslinker are mixed just before application of the coating composition and may optionally cure under ambient conditions without any external energy source.

[0104] Alternatively, the dielectric coating composition may comprise a powder coating composition. “Powder coating composition” as used herein refers to any dielectric coating composition in the form of a co-reactable solid in particulate form which may be substantially free, essentially free, or completely free of water and / or solvent. Suitable film-forming resins useful in dielectric powder coating compositions include those discussed in PCT Publ. No. WO 2021 / 173941A1, pars.

[0006] to

[0042] ,

[0057] to

[0068] ,

[0088] to

[0105] and

[0128] to

[0139] , incorporated herein by reference. Non-limiting examples of suitable powder compositions that may be used in the present disclosure include the polyester-based ENVIROCRON line of powder coating compositions (commercially available from PPG Industries, Inc.), silicon modified polyester compositions, epoxy-polyester hybrid compositions, and / or UV-curable powder compositions.

[0105] The dielectric coating composition may be applied to a substrate by any suitable method known in the art, including but not limited to electrodeposition, coil coating, spraying, such as electrostatic spraying, flow coating, spin coating, curtain coating, brushing, dipping, hot- melt extrusion, application of a self-supporting film, and / or by a fluidized bed process. Onceapplied to the substrate, the dielectric coating composition may be cured by any method known in the art, such as baking, induction heating, infrared heating, and / or exposure to actinic radiation such as UV.

[0106] The dielectric coating formed from the dielectric coating compositions disclosed herein may comprise a dielectric strength of at least 10 kV / mm, such as at least 12 kV / mm, such as at least 15 kV / mm. The dielectric coating may comprise a dielectric strength of no more than 120 kV / mm, such as no more than 100 kV / mm. The dielectric coating may comprise a dielectric strength of 10 kV / mm to 120 kV / mm, such as 12 kV / mm to 100 kV / mm, such as 15 kV / mm to 100 kV / mm. Dielectric strength may be measured using a Sefelec Dielectric Strength Tester (RMG12AC-DC; voltage limit 12.0 kV DC, Imax Limit 0.1 mA, 19 sec ramp, 20 sec dwell, 2 sec fall) according to ASTM D149-09. Additive Manufacturing

[0107] The compositions disclosed herein may be used in any suitable additive manufacturing technology, such as three-dimensional (3D) printing, extrusion, jetting, and binder jetting. Additive manufacturing refers to a process of producing a part or member by constructing it in layers, such as one layer at a time.

[0108] The present disclosure is also directed to the production of structural articles, such as by way of a non-limiting example, sound damping pads, using an additive manufacturing process, such as 3D printing. 3D printing refers to a computerized process, optionally including artificial intelligence modulation, by which materials are printed or deposited in successive layers to produce a 3D part or member, such as, by way of a non-limiting example, sound damping pads in a battery assembly. A 3D part or member may be produced by depositing successive portions or layers over a base of any spatial configuration and thereafter depositing additional portions or layers over the underlying deposited portion or layer and / or adjacent to the previously deposited portion or layer to produce the 3D printed part or member.

[0109] It will be appreciated that the configuration of the 3D printing process, including the selection of suitable deposition equipment, depends on factors such as the deposition volume, the viscosity of the composition and the complexity of the part being fabricated. Any suitable mixing, delivery, and 3D printing equipment as known to those skilled in the art, may be used. Compositions may be printed or deposited in any size and / or shape of droplets or extrudate, and in any patterns to produce the 3D structure.

[0110] Compositions as disclosed herein may be applied or deposited by any suitable 3D printing method as known to those skilled in the art. First and second components of 2K compositions may be mixed and then deposited, or the first and second components may be deposited separately, such as simultaneously and / or sequentially.

[0111] First and second components may be premixed, i.e., mixed together, prior to application, and then deposited. The mixture may be at least partially reacted or thermoset when the material is deposited; the deposited reaction mixture may react at least in part after deposition and may also react with previously deposited portions and / or subsequently deposited portions of the article such as underlying layers or overlying layers of the article.

[0112] In a non-limiting example, the first and two components may be released from their individual storage containers and pushed, such as pumped through conduits, such as hoses, to a mixer, such as a static or dynamic mixer, wherein the composition may be mixed for a time sufficient to homogenize the composition, wherein the composition may then be released through an outlet. The outlet may be a deposition device, such as a printing head, and / or the materials may exit the mixing unit and be pushed, such as by a pump, through a conduit, such as a hose, to the printing head. The printing head may optionally be mounted on a 3D rotational robotic arm to allow delivery of 3D print compositions to any base in any spatial configuration and / or the base may be manipulated in any spatial configuration during the 3D printing process.

[0113] Alternatively, first and second components may be deposited independently from different printing heads. The first component may be deposited from one printing head and the second component may be deposited from a second printing head. The first and second components may be deposited in any pattern such that the first and second components comprising any deposited layer can react together as well as react with underlying and / or overlying layers to produce the 3D printed part or member.

[0114] Methods provided by the present disclosure include printing the composition on a fabricated part. Methods provided by the present disclosure include directly printing parts.

[0115] Using the methods provided by the present disclosure parts can be fabricated. The entire part can be formed from one of the compositions disclosed herein, one or more portions of a part can be formed from one of the compositions disclosed herein, one or more different portions of a part can be formed using the compositions disclosed herein, and / or one or more surfaces of a part can be formed from a composition provided by the present disclosure. Inaddition, internal regions of a part can be formed from a composition provided by the present disclosure. Uses of the Compositions and Coatings

[0116] The compositions disclosed herein may be formulated into highly loaded compositions (i.e., containing thermally conductive filler in an amount of 50 percent by weight up to 90 percent by weight based on total weight of the composition in combination with thermally expandable material in an amount of at least 0.5 percent by weight based on total weight of the composition) that are pumpable (i.e., each component having a viscosity of no more than 106Pa.s at a shear stress of 1 Hz measured by an Anton Paar MCR 301 rotational rheometer at 25oC using a parallel plate with a diameter of 25 mm (1 mm gap)).

[0117] Following exposure to at least the expansion temperature of the thermally expandable material, the thermally expandable material may have an expansion volume ratio of greater than 1 when measured by SEM, such as at least 2.

[0118] The coating may be cohesive following exposure to the expansion temperature of the thermally expandable material.

[0119] The coating may be non-cohesive / crumbling following exposure to the expansion temperature of the thermally expandable material, which can be useful for removal of the coating from a substrate surface, such as removability of a battery cell from a battery pack.

[0120] The compositions disclosed herein may be used to form coatings having the following properties: (a) a pre-expansion thermal conductivity of at least 0.5 W / m∙K at 25oC measured according to ASTM D7984-21 using a modified transient plane source instrument, such as at least 2 W / m.K; (b) a pre-expansion thermal conductivity that was not significantly reduced by the addition of thermally expandable material; (c) a decrease in thermal conductivity post-expansion relative to pre-expansion thermal conductivity of at least 10%, such as at least 25%; (d) a post-expansion volume ratio of greater than 1, such as at least 2, wherein volumes are measured using a caliper and the coating is cohesive / non-crumbling; (e) a vertical burning test rating of V0 (measured by the UL-94 vertical flame test procedure) (a rating of V0 means that (1) no burning combustion (flaming or glowing) isobserved for more than 10 seconds after a flame is removed from first and second flame exposure, (2) no glowing combustion was observed for more than 30 seconds after a flame is removed from second flame exposure, and (3) no dripping of any flame particles that result in igniting the surgical cotton is observed); (f) a pre-expansion tensile stress of at least 0.5 MPa measured according to ASTM D412-16(2021), such as at least 0.6 MPa, such as at least 0.7 MPa; and / or (g) a pre-expansion tensile strain of at least 5% measured according to ASTM D412- 16(2021), such as at least 6%.

[0121] The combination of properties described above was surprising and unexpected. Substrates

[0122] Compositions described herein may be coated or deposited on, or otherwise contacted with, any substrate or surface, such as, but not limited to metals or metal alloys, polymeric materials, such as plastics including filled and unfilled thermoplastic or thermoset materials, and / or composite materials. Other suitable substrates include, but are not limited to, glass or natural materials such as wood. Substrates may include two or more of any different materials in any combination, such as, but not limited to, two different metals, or a metal and a metal alloy, or a metal and a metal alloy and one or more composite materials.

[0123] Suitable substrates may include, but are not limited to, both flexible and rigid metal substrates such as ferrous metals, aluminum, aluminum alloys, magnesium, titanium, copper, and other metal and alloy substrates. The ferrous metal substrates may include, for example, iron, steel, and alloys thereof. Non-limiting examples of useful steel materials include cold rolled steel, nickel plated cold rolled steel, galvanized (zinc coated) steel, electrogalvanized steel, stainless steel, pickled steel, zinc-iron alloy such as GALVANNEAL, and combinations thereof. Aluminum alloys, such as those, for example, of the 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, or 8XXX series as well as clad aluminum alloys and cast aluminum alloys, such as those, for example, of the A356, 1XX.X, 2XX.X, 3XX.X, 4XX.X, 5XX.X, 6XX.X, 7XX.X, or 8XX.X series also may be used as the substrate. The substrate also may comprise, for example, magnesium, such as magnesium alloys of the AZ31B, AZ91C, AM60B, or EV31A series, titanium and / or titanium alloys, such as those of grades 1-36 including H grade variants, copper and copper alloys, or other non-ferrous metals, as well as alloys of thesematerials. The substrate may comprise a composite material such as a plastic, fiberglass and / or carbon fiber composite.

[0124] It will also be understood that the substrate may comprise a bare substrate or the substrate may be pretreated or pre-coated, at least in part, with one or more layers. Suitable pretreatment solutions may include but are not limited to a zinc phosphate pretreatment solution such as, for example, those described in U.S. Patent Nos. 4,793,867 and 5,588,989, or a zirconium containing pretreatment solution such as, for example, those described in U.S. Patent Nos. 7,749,368 and 8,673,091, all four of which are incorporated herein in their entirety.

[0125] The substrate may be in any form, such as, without limitation, a sheet, a foil, a laminate foil, a pad, a fabricated part, a component, or an article. Compositions comprising the materials disclosed herein may be used to coat a substrate, such as by depositing, applying or contacting the compositions to a substrate surface. The compositions, in an at least partially cured state, may be used in any form, such as but not limited to, a coating, a sealant, an adhesive, a pottant or an encapsulant, such as a solid or gel, a pad, such as a pad formed in-situ or a discrete pre-manufactured or pre-formed pad.

[0126] In examples, the substrate may be a multi-metal article. As used herein, the term “multi-metal article” refers to (1) an article that has at least one surface comprised of a first metal and at least one surface comprised of a second metal that is different from the first metal, (2) a first article that has at least one surface comprised of a first metal and a second article that has at least one surface comprised of a second metal that is different from the first metal, or (3) both (1) and (2).

[0127] The compositions disclosed herein are not limited and may be particularly suitable for use in various transportation applications including automotive applications, commercial transport applications, rail locomotive, marine applications and / or aerospace applications. Suitable substrates for use in the present disclosure include those that are used in the assembly of vehicular bodies (for example., without limitation, door, body panel, trunk deck lid, roof panel, hood, roof and / or stringers, rivets, landing gear components, and / or skins used on an aircraft), vehicular frames, vehicular parts, motorcycles, wheels, and industrial structures and components. As used herein, “vehicle” or variations thereof includes, but is not limited to, civilian vehicles, light and heavy commercial vehicles, civilian and military aircraft, and / or land vehicles such as cars, motorcycles, and / or trucks. The compositions disclosed herein also maybe suitable for use in various industrial applications including appliances, personal electronic devices, circuit boards, and the like, or combinations thereof.

[0128] FIGS. 1 to 9 illustrate non-limiting examples of battery assembly components and constructions as well as non-limiting applications or use of compositions as disclosed herein in said battery assemblies. Although FIGS. 1 to 9 illustrate specific examples of cell shapes and cell arrangements, cells may be arranged in any configuration known to those skilled in the art. Additionally, the compositions disclosed herein, in an at least partially cured state, may be used to form pads, adhesives, coatings, pottants and the like, to provide thermal protection between battery cells, within battery modules and / or within battery packs. These materials may be used on any surface or in any space within such battery assemblies. For example, compositions disclosed herein also may be useful in battery assemblies including, but not limited to, cell to module (FIGS. 3, 4, 6B), module to pack (FIGS. 6C, 7), cell to pack (FIG. 8), and cell to chassis battery assemblies (FIG. 9). Such battery assemblies may be used in, but not limited to, any aforementioned application.

[0129] Battery assemblies may be any combination of one or more battery cells, the interconnects which provide electrical conductivity between them, as well as ancillary components such as, in non-limiting examples, control electronics and components that ensure the necessary structural mechanical and environmental requirements for the operation of a specific battery (for example, without limitation, cell interconnectors such as wires, battery pack enclosures including trays and lids, module enclosures, module frames and frame plates, module racking, cooling and heating components including cooling plates, cooling fins, and cooling tubes, electrical busbars, battery management systems, battery thermal management systems, chargers, inverters and converters).

[0130] Battery cells 10 are generally single unit energy storage containers that may be connected in series or in parallel. Battery cells may be any suitable size or shape known to those skilled in the art, such as but not limited to, cylindrical (FIGS. 1, 4 and 9), prismatic (FIGS. 2, 5- 8) and / or pouch (FIG. 3). Battery cells 10 are enclosed to provide desired mechanical protection and environmental isolation of the cell. For example, cylindrical and prismatic cells may be encased in metal cans, cases, and lids, while pouch cells may be enclosed in multilayer laminate foils. Battery terminals 1 connect the electrodes inside the battery cell to the electrical circuit outside the battery cell, with one being a positive terminal and the other being a negativeterminal. As illustrated in FIG. 4, battery cells 10 may be connected by interconnector wires 5 with other battery cells 10 in series or in parallel to enable an electric current to flow between cells 10.

[0131] As illustrated in FIGS. 3 and 4, battery cells 10 may be arranged in modules 100 comprising multiple cells 10 connected in series or in parallel. The modules 100 may include an at least partial enclosure of the arranged cells 10. Ancillary components, such as those aforementioned, may be included. Spaces of any dimensions may be located between the plurality of cells, ancillary components, base, and / or any interior surface of the module wall or other enclosure 120.

[0132] FIG. 1 illustrates a top-down view of cylindrical battery cells 10 having terminals 1. As shown, the cells are arranged in rows with either cooling tubes 3 or dielectric insulation paper (e-paper) 4 between them. As shown, materials, such as adhesive 6 and / or pottants 7 optionally formed from the compositions disclosed herein in an at least partially cured state, may be positioned between the cells 10, cooling tubes 3 and / or e-paper 4. Optionally, e-paper 4 may be replaced by a coating formed from one of the compositions disclosed herein.

[0133] FIG. 2 illustrates an exploded isometric view of an array of prismatic battery cells 10. As shown, each prismatic cell 10 may comprise a top 11, a bottom, and walls 13 positioned between the top and bottom and each having a surface. As shown, materials, such as pads 8 formed from the compositions disclosed herein in an at least partially cured state, may be positioned between surfaces of cell walls 13 of adjacent cells 10.

[0134] FIG. 3 illustrates a cut-out front view of an array of pouch battery cells 10 in a module 100. The module walls 120 at least partially encase the cells 10. As shown, materials, such as pads 8 formed from the compositions disclosed herein in an at least partially cured state, may be positioned between surfaces of cells 10.

[0135] FIG. 4 illustrates an isometric view of cylindrical cells 10 in a battery module 100. Each cell may comprise a top 11, a bottom 12, and walls 13 positioned between the top and bottom and each having a surface. The top 11 and the bottom 12 may be oppositely charged terminals with one being a positive terminal 1 and the other being a negative terminal (not shown). The battery cells may be connected at their terminals by interconnectors such as wires 5 and the like to enable an electric current to flow between the electric cells. The module 100 or module walls 120 may form a space having a volume. The cells 10 may be positioned within thespace to consume a portion of the volume. The material, such as a pottant 7 formed from the compositions disclosed herein, may be positioned within the space to consume at least a portion of the volume such that the material is adjacent to a surface of a cell wall 13 and / or an interior surface of at least one of the walls 120 of the module 100.

[0136] FIG. 5 illustrates an exploded perspective view of a battery module 100 comprised of one or more arrays of battery cells 10, a cooling fin 230, and a cooling plate 240. Materials, such as pads 8 formed from the compositions disclosed herein in an at least partially cured state, may be positioned between cells 10. Additional pads 8 may be positioned between the cells 10, the cooling fin 230, the cooling plate 240, and / or an interior surface of walls 120. Other pads 8 may be positioned adjacent to an exterior surface of the walls 120.

[0137] FIG. 6 illustrates an isometric view of a battery cell 10 (FIG. 6A) to battery module 100 (FIG. 6B) to battery pack 200 (FIG. 6C) battery assembly. The battery module 100 comprises a plurality of battery cells 10 and the battery pack 200 comprises a plurality of battery modules 100.

[0138] FIG. 7 illustrates a perspective view of a battery pack 200 cutout. The battery pack 200 includes a plurality of battery modules 100 and cells 10 within each module 100. The base of the battery pack 200 comprises a cooling plate 240. Materials such as adhesives 9 formed from the compositions disclosed herein in an at least partially cured state, may be positioned between the cooling plate 240 and interior surface of a wall of the battery pack 200. Materials, such as pads 8 formed from the compositions disclosed herein in an at least partially cured state, may be positioned between cells 10 within modules 100.

[0139] FIG. 8 illustrates an isometric view of a cell 10 to pack battery 200 assembly. Cells 10 are arranged within the pack 200 (without being in separate modules).

[0140] In other cases, the battery cells may be arranged on or within an article such as, but not limited to, a cell to chassis battery assembly, as illustrated in FIG. 9, wherein one or more cells is used to construct the battery assembly without prior assembly of the cells into modules and / or packs. FIG. 9 illustrates an isometric cut-out view of a cell to chassis battery assembly 300. Cells 10 are arranged on a base comprising the undercarriage 55 and supported by the vehicle frame 45 and under the vehicle interior floor 35.

[0141] Any battery assembly may further comprise a thermal management system comprising air or fluid circuits which may be liquid based (for example glycol solutions) or direct refrigerant based Definitions

[0142] For purposes of this detailed description, it is to be understood that the disclosure may assume alternative variations and step sequences, except where expressly specified to the contrary.

[0143] The numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0144] Also, any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[0145] As used herein, “including,” “containing” and like terms are understood in the context of this application to be synonymous with “comprising” and are therefore open-ended and do not exclude the presence of additional undescribed or unrecited elements, materials, ingredients or method steps. As used herein, “consisting of” is understood in the context of this application to exclude the presence of any unspecified element, ingredient or method step. As used herein, “consisting essentially of” is understood in the context of this application to include the specified elements, materials, ingredients or method steps “and those that do not materially affect the basic and novel characteristic(s)” of what is being described.

[0146] In addition, in this application, the use of “or” means “and / or” unless specifically stated otherwise, even though “and / or” may be explicitly used in certain instances.

[0147] As used herein, the terms “on,” “onto,” “applied on,” “applied onto,” “formed on,” “deposited on,” “deposited onto,” and the like mean formed, overlaid, deposited, or provided on, but not necessarily in contact with, a substrate surface. For example, a composition “applied onto” a substrate surface does not preclude the presence of one or more other intervening coating layers or films of the same or different composition located between the composition and the substrate surface.

[0148] As used herein, a “coating composition” refers to a solution, mixture, or a dispersion that can produce a coating on a substrate surface.

[0149] “Coating” as used herein includes films, layers and the like.

[0150] As used herein, an “article” refers to the cured composition as a formed or fabricated solid.

[0151] As used herein, a “sealant composition” refers to a coating composition that forms a sealant in its cured state.

[0152] As used herein, a “sealant” refers to a coating that can provide a protective barrier against moisture, chemicals, and other environmental factors, preventing corrosion and extending the lifespan of components.

[0153] As used herein, a “gap filler composition” refers to a coating composition that forms a gap filler in its cured state.

[0154] As used herein, a “gap filler” refers to a coating that fills a gap and that has a butt joint strength of at least 0.001 N / mm2measured according to ASTM D2095.

[0155] As used herein, an “adhesive composition” refers to a coating composition that forms an adhesive in its cured state.

[0156] As used herein, an “adhesive” refers to a coating that produces a load-bearing joint, such as a load-bearing joint having a lap shear strength of at least 0.05 MPa, as determined according to ASTM D1002-10 using an Instron 5567 machine in tensile mode with a pull rate of 1 mm per minute.

[0157] As used herein, a “structural adhesive” refers to a cured coating that produces a load-bearing joint having a lap shear strength of at least 5 MPa measured according to ASTM D1002-10 using an Instron 5567 machine in tensile mode with a pull rate of 1.3 mm per minute.

[0158] As used herein, a “pottant composition” refers to a curable composition that, when cured, forms a pottant.

[0159] As used herein, a “pottant” refers to an encapsulant.

[0160] As used herein, a “pre-preg” refers to a composition used to pre-impregnate reinforcement fibers prior to cure.

[0161] As used herein, a “liquid shim composition” refers to a curable composition that, when cured, forms a liquid shim.

[0162] As used herein, a “liquid shim” refers to a coating that eliminates gaps between substrate surfaces.

[0163] As used herein, the term “one component” or “1K” refers to a composition in which all of the ingredients may be premixed and stored at ambient conditions or optionally may be premixed and frozen and stored (“pre-mixed frozen” or “PMF” as described below), and wherein the reactive components do not readily react at stored conditions and remain “workable” after mixing. The reactive components of a 1K composition or a PMF composition react only upon activation by an external energy source, under pressure, and / or under shear force, and in the case of PMFs, thawing. External energy sources that may be used to promote curing include, for example, radiation (i.e., actinic radiation such as ultraviolet light) and / or heat. The viscosity of the composition does not double or more for at least 10 days after mixing the ingredients (i.e., the composition remains “workable”).

[0164] As further defined herein, “ambient conditions” generally refer to room temperature (e.g. 23°C) and humidity conditions or temperature and humidity conditions that are typically found in the area in which the composition is applied to a substrate, e.g., at 10oC to 40oC and 5% to 80% relative humidity, while “slightly thermal conditions” are temperatures that are slightly above ambient conditions but are generally below the curing temperature for the composition (i.e., in other words, at temperatures and humidity conditions below which the reactive components will readily react and cure, e.g., > 40oC and less than 220oC at 20% to 80% relative humidity).

[0165] As used herein, the term “two-component” or “2K” refers to a composition in which at least a portion of the reactive components readily associate to form an interaction or react to form a bond (physically or chemically), i.e., cure, without activation from an external energy source, such as at ambient or slightly thermal conditions, when mixed. One of skill in the art understands that the two components of the composition are stored separately from each other and mixed just prior to application of the composition. Two-component compositions may optionally be heated or baked, as described below.

[0166] As used herein, “reactive components” refer to components of the composition containing isocyanate or active hydrogen functional groups, including di-functional isocyanate- containing prepolymer, the first and second difunctional polyols, monofunctional isocyanate- containing molecules, polyfunctional isocyanate-containing molecules, monofunctional alcohols,polyfunctional polyols, additives with hydrogen functional groups such as amine, thiol or hydroxy terminated functionalities and aromatic amine.

[0167] As used herein, the term “cure,” “curing,” and similar terms, means that the components that form the composition are crosslinked (i.e., interact and / or react) to form a coating or a bond. In the case of a 1K composition or a PMF, the composition begins to cure when the components of the composition are subjected to curing conditions that lead to the reaction of the reactive functional groups of the components of the composition. In the case of a 2K composition, the composition begins to cure when the components of the composition are mixed resulting in the reaction of the reactive functional groups of the components of the composition.

[0168] The term “curable,” as used in connection with a coating composition, means that the composition can be cured under ambient and / or slightly thermal conditions.

[0169] As used herein, the term “cohesive,” when used with respect to a coating, means the expanded coating (a coating that has been exposed to at least the expansion onset temperature of the thermally expanded material) is held together as part of a single mass, i.e., the expanded coating does not crumble.

[0170] As used herein, the term “non-cohesive,” when used with respect to a coating, means the expanded coating (a coating that has been exposed to at least the expansion onset temperature of the thermally expanded material) is not held together as part of the same mass, i.e., the expanded coating crumbles.

[0171] As used herein, “dielectric” refers to a coating or composition having a dielectric strength of at least 50 kV / mm measured using a Sefelec Dielectric Strength Tester (RMG12AC- DC; voltage limit 12.0 kV DC, Imax Limit 0.1 mA, 19 sec ramp, 20 sec dwell, 2 sec fall) according to ASTM D149-09.

[0172] As used herein, the “thiol equivalent weight” is determined by dividing the measured Mw of a thiol-containing compound by the average number of thiol functional groups present in the thiol-containing compound.

[0173] As used herein, “aromatic,” when referring to a compound, means that the compound comprises at least one aromatic ring.

[0174] As used herein, “terminal” when used with respect to a functional group, refers to a functional group that is at the end of a polymer or prepolymer backbone or monosubstituted with respect to a monomer.

[0175] As used herein, “monomer” refers to a molecule which can undergo polymerization, thereby contributing repeat units to the structure of a prepolymer or a polymer, as defined in Pure and Applied Chemistry, 1996, 68, 2287 (2289), “Glossary of basic terms in polymer science (IUPAC Recommendations 1996).”

[0176] As used herein, “prepolymer” refers to a molecule comprising a reaction product of 2 or more molecules that can be further polymerized or crosslinked.

[0177] As used herein, “polymer” refers to a molecule having more than 1 repeat unit and includes oligomers and homopolymers.

[0178] As used herein, the term “monofunctional,” when used with respect to a particular functional group, refers to a molecule containing only one such functional group.

[0179] As used herein, the term “difunctional,” when used with respect to a particular functional group, refers to a molecule containing two such functional groups.

[0180] As used herein, the term “polyfunctional,” when used with respect to a particular functional group, refers to a molecule containing more than two functional groups.

[0181] As used herein, “Mw” refers to the weight average molecular weight, for example as measured by gel permeation chromatography using polystyrene standards for calibration. The GPC determination can be performed using a Waters 2695 separation module with a Waters 410 differential refractometer (RI detector), linear polystyrene standards having molecular weights from 580 Da to 365,000 Da, tetrahydrofuran (THF) as the eluent at a flow rate of 0.5 ml min-1, and an Agilent PL Gel Mixed C columns (300 x 7.5 mm, 5 µm) used for separation.

[0182] As used herein, the term “thermally conductive filler” or “TC” filler means a pigment, filler, or inorganic powder that has a thermal conductivity of at least 5 W / m∙K at 25°C measured according to ASTM D7984-21.

[0183] As used herein, the term “non-thermally conductive filler” or “NTC filler” means a pigment, filler, or inorganic powder that has a thermal conductivity of less than 5 W / m∙K at 25°C measured according to ASTM D7984-21.

[0184] As used herein, the term “electrically insulative filler” or “EI filler” means a pigment, filler, or inorganic powder that has a volume resistivity of at least 1 Ω.m measured according to ASTM D257-19.

[0185] As used herein, the term “electrically conductive filler” or “EC filler” means a pigment, filler, or inorganic powder that has a volume resistivity of less than 1 Ω.m measured according to ASTM D257-19.

[0186] As used herein, the term “system” refers to a plurality of compositions for application to a substrate surface that results in a plurality of layers formed on the substrate surface. The system may be part of a production line (such as a factory production line) that produces a finished substrate or that produces a treated substrate suitable for use in additional production lines. Unless indicated to the contrary, reference to a “first composition,” a “second composition,” etc., when used with respect to a “system” is not intended to imply a specific order of treatment but rather is for ease of reference only.

[0187] As used herein, unless indicated otherwise, the term “substantially free” means that a particular material is not purposefully added to a mixture or composition, respectively, and is only present as an impurity in a trace amount of less than 0.05% by weight based on a total weight of the mixture or composition, respectively. As used herein, unless indicated otherwise, the term “essentially free” means that a particular material is only present in an amount of less than 0.01% by weight based on a total weight of the mixture or composition, respectively. As used herein, unless indicated otherwise, the term “completely free” means that a mixture or composition, respectively, does not comprise a particular material, i.e., the mixture or composition comprises 0% by weight of such material. Aspects

[0188] In view of the foregoing description the present disclosure thus relates in particular to the following Aspects 1 to 67 without being limited thereto.

[0189] 1. A composition, comprising: a thiol-containing compound; an oxidant; a thermally expandable material; and a thermally conductive filler.

[0190] 2. The composition of aspect 1, wherein the thiol-containing compound comprises a liquid.

[0191] 3. The composition of aspect 1 or aspect 2, wherein the thiol-containing compound comprises formula (I): HS—R1—SH (I) wherein R1may be a C2-6 alkanediyl, a C6-8 cycloalkanediyl, a C6-10 alkanecycloalkanediyl, a C5-8heterocycloalkanediyl, a substituted C2-6alkanediyl, a substituted C6-8cycloalkanediyl, a substituted C6-10 alkanecycloalkanediyl, a substituted C5-8 heterocycloalkanediyl and / or —[(CHR3)p—X]q—(CHR3)r—; where, each R3independently may be hydrogen or a methyl; each X independently may be O, S, S—S, NH, and / or N(—CH3); p may be an integer from 2 to 6; q may be an integer from 1 to 5; and r may be an integer from 2 to 10, such as each p independently may be 2, 3, 4, 5, and 6, and / or such as each p can be the same and can be 2, 3, 4, 5, or 6.

[0192] 4. The composition of aspect 3, wherein X includes a heteroatom such as O, S, S-S or another bivalent heteroatom radical; a secondary or tertiary amine group, i.e., —NR6—, where R6is hydrogen or methyl; or another substituted trivalent heteroatom.

[0193] 5. The composition of aspect 3 or aspect 4, wherein X is O or S, and R1is — [(—CH2—)p—O—]q—(—CH2—)r— or —[(—CH2—)p—S—]q—(—CH2—)r—.

[0194] 6. The composition of aspect 1 or aspect 2, wherein the thiol-containing compound comprises formula (II): HS—R1—[—S—(CH2)p—O—(—R2—O—)m—(CH2)q—S—R1—]n—SH (II) wherein R1can be a C2-10n-alkylene, C2-6branched alkylene, C6-8cycloalkylene or C6-10alkylcycloalkylene group, heterocyclic, —[(—CH2)p—X]q—(—CH2)r; or —[(—CH2)p—X]q— (—CH2)r— in which at least one —CH2— unit is substituted with a methyl group; R2can be a C2-10 n-alkylene, C2-6 branched alkylene, C6-8 cycloalkylene or C6-14 alkylcycloalkylene group, heterocyclic, —[(—CH2)p—X]q—(—CH2)r; X can be O, S, S-S and —NR6—; R6can be H or methyl; m is an independently selected rational number from 1 to 50; and n is an independently selected integer from 1 to 60; p is an independently selected integer ranging from 2 to 6; q is an independently selected integer ranging from 1 to 5; and r is an independently selected integer from 2 to 10.

[0195] 7. The composition of aspect 1 or aspect 2, wherein the thiol-containing compound comprises formula (III) or formula (IV): B—{R8′CH2CH2—O—(R2—O)mCH2CH2—S—R1—[—S—CH2CH2—O—(R2—O)m—CH2— S—R1]n—SH}z(III) or B—{R8′—S—R1—[—S—CH2CH2—O—(R2—O)m—CH2—S—R1]n—SH}z (IV) wherein B can be a z-valent residue of a polyfunctionalizing agent, R1, R2, n and m can be structures and values discussed above with reference to Formula II, R8can be a moiety which is reactive with a terminal vinyl group or mercapto group, and z is an integer from 3 to 6

[0196] 8. The composition of any of the preceding aspects, wherein the thiol- containing compound comprises an Mw of at least 80 g / mol, such as at least 150 g / mol measured by gel permeation chromatography using polystyrene standards for calibration.

[0197] 9. The composition of any of the preceding aspects, wherein the thiol- containing compound comprises a Mw of no more than 40,000 g / mol, such as no more than 20,000 g / mol measured by gel permeation chromatography using polystyrene standards for calibration.

[0198] 10. The composition of any of the preceding aspects, wherein the thiol- containing compound comprises a Mw of 80 g / mol to 40,000 g / mol, such as 150 g / mol to 20,000 g / mol measured by gel permeation chromatography using polystyrene standards for calibration.

[0199] 11. The composition of any of the preceding aspects, comprising the thiol- containing compound in an amount of at least 10 percent by weight based on total weight of the composition, such as at least 17 percent by weight.

[0200] 12. The composition of any of the preceding aspects, comprising the thiol- containing compound in an amount of no more than 88.5 percent by weight based on total weight of the composition, such as no more than 47 percent by weight.

[0201] 13. The composition of any of the preceding aspects, comprising the thiol- containing compound in an amount of 10 percent by weight to 88.5 percent by weight based on total weight of the composition, such as 17 percent by weight to 47 percent by weight.

[0202] 14. The composition of any of the preceding aspects, wherein the oxidant comprises a metal oxide and / or an organic peroxide.

[0203] 15. The composition of any of the preceding aspects, comprising the oxidant in an amount of at least 1 percent by weight based on total weight of the composition, such as at least 2 percent by weight.

[0204] 16. The composition of any of the preceding aspects, comprising the oxidant in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 7 percent by weight.

[0205] 17. The composition of any of the preceding aspects, comprising the oxidant in an amount of 1 percent by weight to 10 percent by weight based on total weight of the composition, such as 2 percent by weight to 7 percent by weight.

[0206] 18. The composition of any of the preceding aspects, wherein the thermally expandable material comprises an inorganic salt, thermally expandable graphite, and / or a thermally expandable capsule, such as a thermally expandable capsule comprising a thermoplastic resin and / or a volatile material.

[0207] 19. The composition of any of the preceding aspects, wherein the thermally expandable material has an expansion temperature of at least 60oC, such as at least 90oC.

[0208] 20. The composition of any of the preceding aspects, wherein the thermally expandable material has an expansion temperature of no more than 250oC, such as 60oC to 250oC.

[0209] 21. The composition of any of the preceding aspects, comprising the thermally expandable material in an amount of at least 0.5 percent by weight based on total weight of the composition, such as at least 1 percent by weight.

[0210] 22. The composition of any of the preceding aspects, comprising the thermally expandable material in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 3 percent by weight.

[0211] 23. The composition of any of the preceding aspects, comprising the thermally expandable material in an amount of 0.5 percent by weight to 10 percent by weight based on total weight of the composition, such as 1 percent by weight to 3 percent by weight.

[0212] 24. The composition of any of the preceding aspects, wherein the filler comprises a TC / EI filler and / or a TC / EC filler, and wherein the composition optionally further comprises an NTC / EI filler.

[0213] 25. The composition of aspect 24, comprising the thermally conductive filler in an amount of at least 20 percent by volume based on total volume of filler, such as at least 50 percent by volume.

[0214] 26. The composition of aspect 24 or aspect 25, comprising the thermally conductive filler in an amount of 100 percent by volume based on total volume of filler.

[0215] 27. The composition of any of aspects 24 to 26, comprising the thermally conductive filler in an amount of no more than 90 percent by volume based on total filler volume, such as no more than 80 percent by volume.

[0216] 28. The composition of any of aspects 24 to 27, comprising the thermally conductive filler in an amount of 20 percent by volume to 100 percent by volume based on total filler volume, such as 20 percent by volume to 90 percent by volume.

[0217] 29. The composition of any of aspects 24 to 28, comprising the thermally conductive filler in an amount of 50 percent by volume to 90 percent by volume based on total filler volume, such as 50 percent by volume to 80 percent by volume.

[0218] 30. The composition of any of the preceding aspects, comprising the filler in an amount of at least 1 percent by weight based on total weight of the composition, such as at least 5 percent by weight.

[0219] 31. The composition of any of the preceding aspects, comprising the filler in an amount of no more than 80 percent by weight based on total weight of the composition, such as no more than 75 percent by weight

[0220] 32. The composition of any of the preceding aspects, comprising the filler in an amount of 1 percent by weight to 80 percent by weight based on total weight of the composition, such as 5 percent by weight to 75 percent by weight.

[0221] 33. The composition of any of the preceding aspects, wherein the thermally conductive filler is present in an amount of at least 10 percent by weight based on total weight of the composition, such as at least 50 percent by weight.

[0222] 34. The composition of any of the preceding aspects, wherein the thermally conductive filler is present in an amount of no more than 88.5 percent by weight based on total weight of the composition, such as no more than 80 percent by weight.

[0223] 35. The composition of any of the preceding aspects, wherein the thermally conductive filler is present in an amount of 10 percent to 88.5 percent by weight based on total weight of the composition, such as 50 percent to 80 percent by weight.

[0224] 36. The composition of any of the preceding aspects, further comprising an additive and / or a cure additive, such as a cure retarder and / or an accelerator.

[0225] 37. The composition of aspect 36, comprising the cure additive in an amount of at least 0.05 percent by weight based on total weight of the composition, such as at least 0.1 percent by weight.

[0226] 38. The composition of aspect 36 or aspect 37, comprising the cure additive in an amount of no more than 10 percent by weight based on total weight of the composition, such as no more than 5 percent by weight.

[0227] 39. The composition of any of aspects 36 to 38, comprising the cure additive in an amount of 0.05 percent by weight to 10 percent by weight, such as 0.1 percent by weight to 5 percent by weight.

[0228] 40. The composition of any of aspects 36 to 39, comprising the additive in an amount of at least 0.5 percent by weight, such as at least 1 percent by weight.

[0229] 41. The composition of any of aspects 36 to 40, comprising the additive in an amount of no more than 20 percent by weight, such as no more than 17 percent by weight.

[0230] 42. The composition of any of aspects 36 to 41, comprising the additive in an amount of 0.5 percent by weight to 20 percent by weight, such as 1 percent by weight to 17 percent by weight.

[0231] 43. The composition of any of the preceding aspects, formulated as a coating composition such as an adhesive composition, a structural adhesive composition, a pottant composition, a foam, a pre-preg, a liquid shim composition, a sealant composition, or a gap filler composition.

[0232] 44. The composition of any of the preceding aspects, wherein the thermally expandable material has an expansion volume ratio of at least 5, such as at least 25.

[0233] 45. The composition of any of the preceding aspects, wherein the thermally expandable material has an expansion volume ratio of no more than 250.

[0234] 46. The composition of any of the preceding aspects, wherein the thermally expandable material has an expansion volume ratio of 5 to 250, such as 25 to 250.

[0235] 47. A substrate comprising a coating formed from the composition of any of the preceding aspects on a surface thereof.

[0236] 48. The substrate of aspect 47, further comprising a dielectric coating on the surface.

[0237] 49. The substrate of aspect 47 or aspect 48, wherein the substrate comprises a battery cell.

[0238] 50. A battery comprising the substrate of aspect 49, and optionally a battery component.

[0239] 51. A vehicle comprising the battery of aspect 50, such as a land vehicle and / or an aerospace vehicle.

[0240] 52. A method for treating a substrate comprising contacting a surface of the substrate with the composition of any of aspects 1 to 46.

[0241] 53. A use of the composition of any of aspects 1 to 46 for forming a coating having a pre-expansion thermal conductivity of at least 0.5 W / m∙K at 25oC measured according to ASTM D7984-21 using a modified transient plane source instrument, such as at least 2 W / m.K.

[0242] 54. The use of aspect 53, wherein the coating has a decrease in thermal conductivity post-expansion relative to pre-expansion thermal conductivity of at least 10%, such as at least 25%.

[0243] 55. The use of aspect 53 or aspect 54, wherein the coating has a post- expansion volume ratio of greater than 1, such as at least 2, wherein volumes are measured using a caliper and the coating is cohesive / non-crumbling.

[0244] 56. The use of any of aspects 53 to 55, wherein the coating has a vertical burning test rating of V0 (measured by the UL-94 vertical flame test procedure).

[0245] 57. The use of any of aspects 53 to 56, wherein the coating has a pre- expansion tensile stress of at least 0.5 MPa measured according to ASTM D412-16(2021), such as at least 0.6 MPa.

[0246] 58. The use of any of aspects 53 to 57, wherein the coating has a pre- expansion tensile strain of at least 5% measured according to ASTM D412-16(2021), such as at least 6%.

[0247] 59. The use of any of aspects 53 to 58, wherein the thermally expandable material has an expansion volume ratio of greater than 1 when measured at by SEM, such as at least 2, following exposure to at least the expansion temperature of the thermally expandable material.

[0248] 60. The use of any of aspects 53 to 59, wherein the coating is cohesive following exposure to the expansion temperature of the thermally expandable material.

[0249] 61. The use of any of aspects 53 to 60, wherein the coating is non-cohesive and / or crumbling following exposure to the expansion temperature of the thermally expandable material.

[0250] 62. The use of any of aspects 53 to 61, wherein the coating has a pre- expansion thermal conductivity that is not significantly reduced relative to a coating that does not include a thermally expandable material.

[0251] 63. A system comprising: a dielectric coating composition for application to a surface of a substrate; and the composition of any of aspects 1 to 46 for application on the dielectric coating composition.

[0252] 64. A kit comprising: a dielectric coating composition for application to a surface of a substrate; and the composition of any of aspects 1 to 46 for application on the dielectric coating composition.

[0253] 65. The kit of aspect 64, further comprising instructions for applying the dielectric coating composition and the composition.

[0254] 66. The system or kit of any of aspects 63 to 65, wherein the dielectric coating composition comprises: a binder comprising a film-forming resin such as a polyester, alkyl, urethane, isocyanate, polyurea, epoxy, acrylic, polyether, polysulfide, polyamine, polyamide, polyvinyl chloride, polyolefin, polyvinylidene fluoride, polyvinyl chloride, polyolefin, polysiloxane, amine- aldehydes, resinous polyols, phosphatized polyepoxides, phosphatized acrylic polymers, aminoplasts, or combinations thereof; and / or a curing agent and / or crosslinker capable of crosslinking with the film-forming resin to cure the dielectric coating composition, such as an amine, aminoplast, phenoplast,polyisocyanate, including blocked isocyanate, polyepoxide, beta-hydroxyalkylamide, polyacid, organometallic acid-functional material, polyamine, polyamide, polysulfide, polythiol, polyene such as polyacrylate, polyol, polysilane and the like, or combinations thereof.

[0255] 67. The system or kit of any of aspects 63 to 66, wherein the dielectric coating composition comprises a powder coating composition and / or a liquid coating composition such as an electrodepositable coating composition, a UV-curable coating composition, and / or a solvent-based coating composition.

[0256] Illustrating the disclosure are the following examples, which, however, are not to be considered as limiting the disclosure to their details. Unless otherwise indicated, all parts and percentages in the following examples, as well as throughout the specification, are by weight. EXAMPLES

[0257] The following examples are intended to illustrate the disclosure and should not be construed as limiting the disclosure in any way.

[0258] The adhesive compositions described below were prepared according to the following procedures with all non-manual mixing performed using a Speedmixer DAC 600FVZ (commercially available from FlackTek, Inc.).

[0259] Part A was prepared by combining all the components listed under “Resins and dispersants” in the tabulated order. The materials were mixed on the DAC mixer for 1–2 minutes at 2000 rpm. The “Fillers” were then added, and the mixture was mixed for 1–2 minutes at 2000 rpm. The mixture was examined with a spatula and mixed manually. As necessary, the high- speed mixing was repeated to ensure uniformity. Part B was PS-890 B2, commercially available from PRC DeSoto, Inc., and prepared according to manufacturer instructions. At the application stage, parts A and B were combined and mixed at 2000 rpm for 1–2 minutes. The mixed parts A and B were pressed into sheets (3 mm thickness) using a Carver laboratory press (commercially available from Fred S. Carver, Inc.). One set of sheets for each composition was subsequently cured at ambient temperature for 7 days and one set of sheets for each composition was subsequently cured by accelerated cure according to AMS3276 Rev H (Section 4.5.4.5) using B class materials.

[0260] Samples for testing tensile strength were prepared by cutting the cured sheets into dogbones. The tensile properties were measured by ASTM D412-16(2021) using an Instron model 3345.

[0261] Samples for testing thermal conductivity and thermal expansion were prepared by cutting out circular pieces (diameter ~33 mm). The dimensions of each sample were measured pre- and post-expansion using a caliper, and these metrics were used to determine the volume expansion ratio (∆V). Thermal expansions were performed in an oven preheated to 120°C for samples containing Expancel 043 du 80. Each sample was thermally expanded with a weight atop (weight 500 g and diameter 40 mm) to exert a pressure of 3.2 kPa.

[0262] Thermal conductivity of each sample was measured pre- and post-expansion using a TCi Thermal Conductivity Analyzer (commercially available from C-therm). For pre- expansion samples, the ceramic materials method was used with deionized water as the contact agent. For post-expansion samples, the polymer material method was used with Wakefield Type 120 Silicone thermal grease as the contact agent. If the sample thermal conductivity fell below the polymer calibration method range, the foam materials method was used with no contact agent. Composition 1 Composition 2 Composition 3 (g) (g) (g) (Comparative)PS-890 B2 Part A 6.06 6.06 6.06 Results (Ambient Cure)

[0263] The examples illustrate that compositions that include expandable material lose thermal conductivity post-thermal event, while compositions that do not include expandable material maintain mechanical properties and thermal conductivity. Additionally, thermal conductivity of coatings pre-expansion was not significantly reduced by the inclusion of thermally expandable material (1.6 W / mK to 1.3 W / mK). Finally, all of the coatings were cohesive.

[0264] Whereas specific aspects of the disclosure have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of thedisclosure which is to be given the full breadth of the claims appended and any and all equivalents thereof.

Claims

We claim:

1. A composition, comprising: a thiol-containing compound; an oxidant; a thermally expandable material; and a thermally conductive filler.

2. The composition of claim 1, wherein the thiol-containing compound comprises a liquid.

3. The composition of claim 1 or claim 2, wherein the thiol-containing compound comprises an average molecular weight (Mw) of 80 g / mol to 40,000 g / mol measured by gel permeation chromatography (GPC) using polystyrene standards for calibration.

4. The composition of any of the preceding claims, wherein the oxidant comprises a metal oxide and / or an organic peroxide.

5. The composition of any of the preceding claims, wherein the thermally expandable material comprises a pre-expansion average particle size of at least 0.5 µm measured by laser diffraction.

6. The composition of any of the preceding claims, comprising: the thiol-containing compound and the oxidant in a total amount of 10 by weight to 88.5 percent by weight based on total weight of the composition; the thermally expandable material in an amount of 0.5 percent by weight to 10 percent by weight based on total weight of the composition; and / or the thermally conductive filler in an amount of 10 percent by weight to 88.5 percent by weight based on total weight of the composition.

7. A method for treating a substrate comprising: contacting a surface of the substrate with the composition of any of the preceding claims.

8. A substrate comprising a coating on a surface thereof, formed from the composition of any of claims 1 to 6.

9. The substrate of claim 8, further comprising a dielectric coating on the surface.

10. The substrate of claim 8 or claim 9, wherein the substrate comprises a battery cell.

11. A battery comprising the battery cell of claim 10.

12. A vehicle comprising the battery of claim 11.

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