SILICONE RESIN COATING COMPOSITIONS CONTAINING BLOCKED ISOCYANATES

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] None.

DESCRIPTION

[0002] Carbinol functional siloxane resins have been shown previously to add thermal stability, weatherability, scratch resistance and reduce water absorption when formulated with isocyanates to make urethane coatings. However, these formulations must be provided to the end user in a two part system since the shelf life or pot life is limited to hours once mixed. Since isocyanates are reactive with water and have toxicity issues, it would be useful to be able to make a one part coating compositions which does not form an isocyanate until the coating composition is in place and ready to be cured. The inventors have determined that shelf stable one part curable coating compositions based on carbinol functional siloxane resins may be prepared by using blocked isocyanates. Curing of these coating compositions only occur in the presence of heat. Applications such as automotive top coats, electronics packaging, and specialty adhesives prefer a one-part delivery to avoid poor performance due to formulating and mixing issues at the application site.

[0003] This invention relates to curable compositions comprising (A) at least one compound containing at least two blocked isocyanate groups per molecule; and

(B) at least one carbinol-functional silicone resin comprising the units:

(Rl ₃ SiO ₁₇₂ ) _S (i)

(R ³ Si0 ₃ / ₂ )c (iϋ) and (SiO _4/2 )d (iv) wherein R^ and R^ are each independently a hydrogen atom, an alkyl group, an aryl group, a carbinol group free of aryl groups having at least 3 carbon atoms, or an aryl-containing carbinol group having at least 6 carbon atoms, R^ is an alkyl group having from 1 to 8 carbon atoms or an aryl group, a has a value of less than or equal to 0.6, b has a value of zero or

greater than zero, c has a value of greater than zero, d has a value of less than 0.5, and the value ofa + b + c + d = 1, and with the provisos that when each R^ is methyl the value of b is less than 0.3 and there is on average at least one carbinol group per resin molecule; where the mole ratio of blocked isocyanate groups to carbon-bonded hydroxyl groups is from 0.9:1 to 1.3:1.

[0004] Another embodiment of the invention relates to a method of making curable coating compositions comprising:

(1) Forming a mixture comprising (A) at least one compound containing at least two blocked isocyanate groups per molecule; (B) at least one carbinol-functional silicone resin comprising the units:

(R ³ Siθ3/2) _c (iϋ) and (SiO ₄ / ₂ )d (iv) wherein RI and R^ are each independently a hydrogen atom, an alkyl group, an aryl group, a carbinol group free of aryl groups having at least 3 carbon atoms, or an aryl-containing carbinol group having at least 6 carbon atoms, R^ is an alkyl group having from 1 to 8 carbon atoms or an aryl group, a has a value of less than or equal to 0.6, b has a value of zero or greater than zero, c has a value of greater than zero, d has a value of less than 0.5, and the value of a + b + c + d = 1, and with the provisos that when each R^ is methyl the value of b is less than 0.3 and there is on average at least one carbinol group per resin molecule; where the mole ratio of blocked isocyanate groups to carbon-bonded hydroxyl groups is from 0.9:1 to 1.3:1. [0005] Another embodiment of the invention relates to a method of making cured coating compositions comprising

(1) forming a mixture comprising

(A) at least one compound containing at least two blocked isocyanate groups per molecule;

(B) at least one carbinol-functional silicone resin comprising the units: (R^SiO^a 0)

(R ³ Siθ3/2) _c (iϋ) and (SiO _4/2 )d (iv) wherein R^ and R^ are each independently a hydrogen atom, an alkyl group, an aryl group, a carbinol group free of aryl groups having at least 3 carbon atoms, or an aryl-containing carbinol group having at least 6 carbon atoms, R^ is an alkyl group having from 1 to 8 carbon atoms or an aryl group, a has a value of less than or equal to 0.6, b has a value of zero or greater than zero, c has a value of greater than zero, d has a value of less than 0.5, and the value ofa + b + c + d = 1, and with the provisos that when each R^ is methyl the value of b is less than 0.3 and there is on average at least one carbinol group per resin molecule; where the mole ratio of blocked isocyanate groups to carbon-bonded hydroxyl groups is from 0.9:1 to 1.3:1;

(2) Heating the mixture to greater than 9O ⁰ C so that the blocked isocyanate dissociates to the corresponding isocyanate which enables the curing reactions to proceed. [0006] Other embodiments of the invention relate to the curable and cured coating compositions prepared by the methods described above.

[0007] Component (A) can be any compound having at least two blocked isocyanate groups per molecule where such isocyanate groups can be accessed by heating the compound to remove the blocking group. Examples of isocyanate compounds which can have blocking groups include any multi-isocyanate group containing molecules which have been used previously in the preparation of crosslinked methanes. The compounds containing at least two isocyanate groups of Component (A) are illustrated by isophorone diisocyanate trimers, isophorone diisocyanate, toluene diisocyanate, polyisocyanates, tetramethylxylylene diisocyanate, phenylene diisocyanate, xylene diisocyanate, 1,5 -naphthalene diisocyanate, chlorophenylene 2,4-diisocyanate, bitoluene diisocyanate, dianisidine diisocyanate, toluidine diisocyanate and alkylated benzene diisocyanates generally; methylene-interrupted aromatic diisocyanates such as methylene-diphenyl-diisocyanate, especially the 4,4'-isomer (MDI) including alkylated analogs such as 3,3'-dimethyl-4,4'-diphenyl-methane diisocyanate; such hydrogenated materials as cyclohexylene diisocyanate, 4,4'-methylenedicyclohexyl diisocyanate; mixed aralkyl diisocyanates such as the tetramethylxylyl diisocyanates,

OCNC(CH3)2C6H4C(CH3)2NCO, and the diisocyanate popularly referred to as isophorone diisocyanate, which is 3,3,5-trimethyl-5-isocyanato-methylcyclohexyl isocyanate; and polymethylene isocyanates such as 1,4-tetramethylene diisocyanate, 1 ,5-pentamethylene diisocyanate, 1 ,6-hexamethylene diisocyanate (HMDI), 1 ,7-heptamethylene diisocyanate, 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate, 1,10-decamethylene diisocyanate, and 2 -methyl- 1 ,5-pentamethylene diisocyanate.m-phenylene.

[0008] As used herein, the term "blocked" refers to a compound that has been reacted with a second compound (i.e. "blocking group") such that its reactive functionality is not available until such time as the blocking group is removed, for example by heating, or by further reaction, such as with water. Examples of blocked isocyanates include isocyanate functional compounds that have been co-reacted with phenol, methyl ethyl ketoxime, and epsilon- caprolactam. The blocking agents useful in the present invention generally contain an active hydrogen, (hydrogen attached to oxygen, sulfur or nitrogen) which will react with the diisocyanates and the product is reversible, that is deblocks, thermally. Representative blocking agents are derivatives selected from oximes, lactams, phenols, active methylenes, pyrazoles, mercaptans, imidazoles, amines, imines, triazoles, hydroxyl amines, and aliphatic, cycloaliphatic or aromatic alkyl monoalcohols. Alternatively, the blocking groups are derivatives of oximes and lactams. The above blocked isocyanates can be used alone or in, combination. [0009] Commercially available materials suitable as component (A) are illustrated by Tolonate® D2 (Rhodia, Cranbury,NJ) a methyl ethyl ketoxime blocked hexamethyldiisocyanate (HDI) derived compound delivered as 75% solids in aromatic solvent (equivalent weight 370 g/mol blocked isocyanate groups), Desmodur® BL-3175A (Bayer, Pittsburgh, PA) a butanone oxime blocked HDI isocyanurate, and Desmocap® 1 IA (Bayer, Pittsburgh, PA) a phenol blocked toluenediisocyanate prepolymer.

[0010] The blocked isocyanate compound has on average at least two blocked isocyanate groups per molecule. The equivalent weight of blocked isocyanate groups on the blocked isocyanate compound may be from 100 to 1000, alternatively 200 to 800. [0011] Component (B) comprises at least one carbinol-functional silicone resin comprising the units:

(SiO _4/2 )d (iv) wherein R^ and R^ are each independently a hydrogen atom, an alkyl group, an aryl group, a carbinol group free of aryl groups having at least 3 carbon atoms, or an aryl-containing carbinol group having at least 6 carbon atoms, R^ is an alkyl group having from 1 to 8 carbon atoms or an aryl group, a has a value of less than or equal to 0.6, b has a value of zero or greater than zero, c has a value of greater than zero, d has a value of less than 0.5, and the value ofa + b + c + d = 1, and with the provisos that when each R^ is methyl the value of b is less than 0.3 and there is on average at least one carbinol group per resin molecule. [0012] For the purposes of this invention "carbinol group" is defined as any group containing at least one carbon-bonded hydroxyl (COH) group. Thus the carbinol groups may contain more than one COH group such as for example

[0013] The alkyl groups of R^ and R^ in the carbinol-functional silicone resin of Component (B) are illustrated by methyl, ethyl, propyl, butyl, pentyl, hexyl, and octyl.

Alternatively, the alkyl groups of Rl and R^ have 1 to 8 carbon atoms, and alternatively are methyl. The aryl groups of R^ and R^ are illustrated by phenyl, naphthyl, benzyl, tolyl, xylyl, methylphenyl, 2-phenylethyl, 2-phenyl-2-methylethyl, chlorophenyl, bromophenyl and fluorophenyl. Alternatively, the aryl groups of R^ and R^ have 6 to 8 carbon atoms, and alternatively are phenyl. [0014] The carbinol group free of aryl groups having at least 3 carbon atoms is illustrated by groups having the formula R^OH wherein R^ is a divalent hydrocarbon group having at least 3 carbon atoms or a divalent hydrocarbonoxy group having at least 3 carbon atoms. The group R4 is illustrated by alkylene groups selected from -(CH2) _X - where x has a value of 3 to 10, -CH ₂ CH(CH ₃ )-, -CH ₂ CH(CH ₃ )CH ₂ -, -CH ₂ CH ₂ CH(CH ₂ CH ₃ )CH ₂ CH ₂ CH ₂ -, and

-OCH(CH3)(CH2)y- wherein y has a value of 1 to 10. The carbinol group free of aryl groups having at least 3 carbon atoms is also illustrated by groups having the formula

R ⁶ (OH) CH2OH and R ⁶ is a group having the formula -CH2CH2(CH2) _y OCH2CH- wherein y is as described above. [0015] The aryl-containing carbinol group having at least 6 carbon atoms is illustrated by groups having the formula R^OH wherein R^ is an arylene group selected from -(CH ₂ ) _Z C ₆ H4- or -CH ₂ CH(CH ₃ )(CH ₂ ) _Z C ₆ H4- wherein z has a value of 0 to 10, and -

(CH ₂ )yC ₆ H4(CH ₂ )y- wherein y has a value of 1 to 10. The aryl-containing carbinol groups may have from 6 to 14 carbon atoms, alternatively 6 to 10 carbon atoms. [0016] In the carbinol-functional silicone resin, Component (B), subscript a has a value of 0.1 to 0.6, alternatively 0.2 to 0.4, subscript b has a value of 0 to 0.4, alternatively 0 to 0.1, subscript c has a value of 0.3 to 0.8, alternatively 0.4 to 0.8, subscript d has a 1 value of 0 to

0.3, alternatively zero. When each R ² is methyl the value of subscript b is less than 0.3, alternatively less than 0.1. [0017] The carbinol-functional silicone resins have on average at least one carbinol group per resin molecule. The equivalent weight of carbon-bonded hydroxyl groups on the carbinol-functional silicone resin may be from 100 to 1000, alternatively 200 to 800.

[0018] When R^ or R ² of the carbinol-functional silicone resin contains a carbinol group, only one carbinol group will be present on each such R^ or R ² . [0019] The carbinol-functional silicone resins of Component (B) are illustrated by carbinol-functional silicone resins comprising the units: ((CH ₃ ) ₃ Si0 ₁ /2)a

((R ² )CH ₃ Si0 ₂ /2)b where R ² = -(CH ₂ )3C ₆ H ₄ OH ((C ₆ H ₅ )CH ₃ SiO ₂ /2)b and (C ₆ H ₅ SiO ₃₇₂ ) _C carbinol-functional silicone resins comprising the units:

((R ¹ )(CH ₃ ) ₂ SiOi/2) _a where R ¹ = -(CH ₂ ^C ₆ H ₄ OH and

(C ₆ H ₅ SiO ₃ Z ₂ ) _C carbinol-functional silicone resins comprising the units:

((R ¹ )(CH ₃ )2SiOi/2) _a where R ¹ = -(CH ₂ )3C6H ₄ OH and (CH ₃ Si0 ₃ /2) _c , carbinol-fϊinctional silicone resins comprising the units: ((R ¹ )(CH3) ₂ SiOi/2)a where R ¹ = -(CH ₂ )3θH and (C ₆ H ₅ SiO ₃₇₂ ) _C , carbinol-functional silicone resins comprising the units: ((R ¹ )(CH ₃ ) ₂ SiOi/ ₂ )a where R ¹ = -(CH ₂ ) ₃ OH (CH ₃ Si0 _3/2 ) _c and (C ₆ H ₅ SiO ₃₇₂ ) _C carbinol-functional silicone resins comprising the units: ((CH ₃ ) ₃ Si0 ₁₇₂ )a

((R ² )CH ₃ Si0 ₂₇₂ )b where R ² = -(CH ₂ ) ₃ OH ((C ₆ H ₅ )CH ₃ SiO ₂₇₂ ) _b and (C ₆ H ₅ Si0 ₃₇₂ ) _c , carbinol-functional silicone resins comprising the units: ((CH ₃ ) ₃ SiOi ₇₂ )a

where R ¹ = -(CH ₂ ) ₃ OH and

(C ₆ H ₅ SiO ₃₇₂ ) _C carbinol-functional silicone resins comprising the units: -CH ₂ CH(CH ₃ )CH ₂ OH

((H)(CH ₃ ) ₂ SiOi ₇₂ )a and

(C ₆ H ₅ SiO ₃₇₂ ) _C and carbinol-functional silicone resins comprising the units:

((Rl)(CH ₃ ) ₂ SiOi/ ₂ )a where Rl = -(CH ₂ ) ₃ OH (CH ₃ SiO ₃₇₂ ) _C where a, b and c are as defined above

[0020] If desired, the R1+R ² +R-> groups in the carbinol-functional silicone resin may contain high enough aryl group content to provide appropriate compatibility with component

(A). Alternatively, greater than 10 weight percent of the R1+R2+R3 groups are aryl groups. Alternatively, greater than 25 weight percent of the R!+R2+R3 groups are aryl groups such as phenyl.

[0021] The carbinol-functional silicone resins useful in the present invention are prepared by methods described in the art, in particular US20060235142 and WO2005/037887 which are herein incorporated by reference. Generally, the carbinol-functional silicone resins are prepared by reacting: (A') at least one hydrogen-functional silicone resin comprising the units: (R ⁸ 2Siθ2/2)f (vi)

(R ³ Siθ3/2) _g (vii) and (SiO _4/2 )h (viϋ) wherein R^ and R° are each independently an alkyl group having from 1 to 8 carbon atoms, an aryl group, or a hydrogen atom, e has a value of less than or equal to 0.6, f has a value of zero or greater than zero, g has a value of greater than zero, h has a value of less than 0.5, and the value of e + f + g + h = 1, R^ is as defined above, with the proviso that when each R^ is methyl the value of f is less than 0.3, with the proviso that there are at least two silicon- bonded hydrogen atoms present in the silicone resin; and (B') at least one alkenyl -terminated alcohol; in the presence of (C) a hydrosilylation catalyst; and optionally (D') at least one solvent.

[0022] The alkyl groups and aryl groups of R^ and R° are as described above for Rl and

R2. Subscripts e, f, g, and h are as described above for a, b, c, and d respectively. [0023] Optionally, one may also add an organic polyol (Component (C)) to the coating composition. The organic polyol (synonymous with organic carbinol) is illustrated by ethylene glycol, 1 ,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 2,3-butylene glycol, 1 ,6-hexanediol, 1 ,8-octanediol, neopentyl glycol, cyclohexane dimethanol, 2-methyl- 1,3-propanediol, glycerol, trimeth 1,2,61, 1 ,2,4-butanetriol, pentaerythritol, mannitol, sorbitol, diethylene glycol, triethylene glycol, tetraethylene glycol, poly(ethyleneoxy) glycols generally, dipropylene glycol, poly(propyleneoxy) glycols generally, dibutylene glycol, poly(butyleneoxy) glycols, and polycaprolactone. Other polyhydroxy materials of higher

molecular weight which may be used are the polymerization products of epoxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, and epichlorohydrin. Hydroxyl-containing polyesters, polythioethers, polyacetals, polycarbonates, and polyester amides also may be used alone or in combination with the above polyols. Suitable polyesters include the reaction product of polyhydric alcohols and polybasic, preferably dibasic, carboxylic acids. The polyhydric alcohols which are often used include the dihydric alcohols mentioned above. Examples of dicarboxylic acids include succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, glutaric acid, phthalic acid, maleic acid, and fumaric acid. Typical polyether polyols are illustrated by polyalkylene ether polyols having the formula HO(RO) _n H wherein R is an alkylene group and n is an integer large enough that the polyether polyol has a number average molecular weight of at least 250. These polyalkylene ether polyols are well-known components of polyurethane products and can be prepared by the polymerization of cyclic ethers such as alkylene oxides and glycols, dihydroxyethers, and the like by known methods. A particularly common high molecular weight polyol is polytetramethylene glycol.

[0024] The mole ratio of blocked isocyanate groups to total carbon-bonded hydroxyl groups in the coating composition may be from 0.9:1 to 1.3:1. Alternatively, the mole ratio of blocked isocyanate groups to total carbon-bonded hydroxyl groups in the coating composition is from 1 :1 to 1.2:1 As used herein "total carbon-bonded hydroxyl groups" refers to carbon-bonded hydroxyl groups from carbinol groups from component (B) and the polyol from component (C).

[0025] Optionally, one may add a cure rate modifier (Component (D)) to the coating composition. Component (D), the cure rate modifier can be any material that affects the cure time of the coating composition and includes cure accelerators, cure inhibitors, and cure catalysts. Examples include phosphine compounds, such as tributylphosphine, triphenylphosphine, tris(dimethoxyphenyl)phosphine, tris(hydroxypropyl)phosphine and tris(cyanoethyl)phosphine; phosphonium salts, such as tetraphenylphosphonium tetraphenylborate, methyltributylphosphonium tetraphenylborate and methyltricyanoethyl phosphonium tetraphenylborate; imidazoles, such as 2-methyl imidazole, 2-phenyl imidazole, 2-ethyl-4-methyl imidazole, 2-undecyl imidazole, 1 -cyanoethyl-2 -methyl imidazole, 1,4- dicyano-6-[2-methylimidazolyl-(l)]-ethyl-S-triazine and 2,4-dicyano-6-[2- undecylimidazolyl-(l)]-ethyl-S-triazine; imidazolium salts, such as l-cyanoethyl-2-

undecylimidazolium trimellitate, 2-methylimidazolium isocyanurate, 2-ethyl-4- methylimidazolium tetraphenylborate and 2-ethyl-l,4-dimethylimidazolium tetraphenylborate; amines, such as 2,4,6-tris(dimethylaminomethyl)phenol, benzyl dimethylamine, tetramethylbutyl guanidine, N-methyl piperazine and 2-dimethylamino-l- pyrroline; ammonium salts, such as triethylammonium tetraphenylborate; diazabicyclo compounds, such as l,5-diazabicyclo(5,4,0)-7-undecene, l,5-diazabicyclo(4,3,0)-5-nonene and 1 ,4-diazabicyclo(2,2,2)-octane; and tetraphenylborates, phenol salts, phenol novolak salts and 2-ethylhexanoates of those diazabicyclo compounds, and alcohols such as resorcinol. Of these compounds tertiary amines, phosphine compounds, imidazole compounds, diazabicyclo compounds and their salts are typically used. Dicyandiamide and boron trifluoride may also be used.

[0026] The cure rate modifier Component (D) can also be illustrated by compounds having an aliphatic unsaturated bond, organophosphorous compounds, organosulfur compounds, nitrogen-containing compounds, and tin compounds. Examples of the compounds having an aliphatic unsaturated bond include propargyl alcohol, ene-yne compounds, and maleic esters such as dimethyl maleate. Examples of the organophosphorus compounds are triorganophosphines, diorganophosphines, organophosphones, and triorganophosphites. The organosulfur compounds include organomercaptanes, diorganosulfides, hydrogen sulfide, benzothiazole, and benzothiazole disulfite. The nitrogen-containing compounds include ammonia, primary, secondary or tertiary alkylamines, arylamines, urea, and hydrazine. The amines are illustrated by triethylamine, tributylamine, N-methylmorpholine, N- ethylmorpholine, l,4-diaza-bicylo-(2,2,2)-octane, N-cetyl dimethylamine, N-methyl-N'- dimethylaminoethyl-piperazine, N,N-dimethylbenzylamine, N,N-dimethylcyclohexylamine, and 1,2-dimethylimidazole. Organic tin compounds may also be used and include such materials as the tin(II) salts of carboxylic acids such as tin(II) acetate, tin(II) octoate, tin(II) ethylhexoate and tin(II) laurate, as well as such materials as the dialkyl tin salts of carboxylic acids as exemplified by dibutyltindiacetate, dibutyltindilaurate, dibutyltinmaleate, and dioctyltindiacetate. Such tin salts may be used either alone or as a complex with amidines such as amino pyridines, amino pyrimidines, hydrazino pyridines, and tetrahydropyrimidines. Other metal-based compounds such as lead, iron, mercury, bismuth, cobalt and manganese also may be used, and include compounds such as cobalt(III) acetylacetonate, cobalt naphthoate, manganese naphthoate, lead oleate, zinc naphthenate and zirconium naphthenate.

Other compounds such as silaamines and basic nitrogen compounds such as tetraalkylammonium hydroxide, alkali metal hydroxides such as sodium hydroxide, and alkali metal alcoholates such as sodium methylate may also be used.

[0027] When it is desirable to add the cure rate modifier (Component (D)) to the coating composition, generally it will be added in amounts from 0.001 to5 parts by weight based on total weight of the coating formulation, alternatively from 0.1 to 2 parts by weight on the same basis.

[0028] The coating compositions of the present invention may further comprise other components that are conventionally employed in polymerizable systems. These components include, but are not limited to, solvents, plasticizers, pigments, colorants, dyes, surfactants, thickeners, heat stabilizers, leveling agents, anti-cratering agents, fillers, sedimentation inhibitors, ultraviolet-light absorbers, and the like. Additives such as promoters, heat stabilizers, ultraviolet-light absorbers, etc. may be intimately dispersed in the reaction mixture and apparently thereby become an integral part of the polymer. Preferred antioxidants are sterically hindered phenolic compounds. Stabilizers such as organic phosphites are also useful. Preferred UV inhibitors are benzotriazole compounds. [0029] The coating compositions of this invention can further comprise at least one filler illustrated by hollow microspheres, fumed silica, precipitated silica, hydrous silicic acid, carbon black, ground quartz, calcium carbonate, magnesium carbonate, diatomaceous earth, wollastonite, calcined clay, clay, talc, kaolin, titanium oxide, bentonite, ferric oxide, zinc oxide, glass balloon, glass beads, mica, glass powder, glass balloons, coal dust, acrylic resin powder, phenolic resin powder, ceramic powder, zeolite, slate powder, organic fibers, and inorganic fibers. [0030] The coating compositions of this invention can further comprise at least one cell stabilizer and at least one blowing agent, and optionally chain extenders and crosslinkers. The cell stabilizers are illustrated by silicones, with silicone polyethers being typically used. The blowing agents are illustrated by water, liquid carbon dioxide, CFCs, HCFCs, HFCs, and pentane, with water or a mixture of water and HCFC being typically used. The addition of these ingredients to the urethane compositions of this invention produce polyurethane foam compositions having enhanced thermal stability.

[0031] The coating compositions of this invention may be prepared by mixing (or mechanically agitating) components (A) and (B), and any optional components, to form a

homogenous mixture. This may be accomplished by any convenient mixing method known in the art exemplified by a spatula, mechanical stirrers, in-line mixing systems containing baffles and/or blades, powered in-line mixers, homogenizers, a drum roller, a three-roll mill, a sigma blade mixer, a bread dough mixer, and a two roll mill. The order of mixing is not considered critical. Once mixed, the coating composition is shelf stable and will not cure until exposed to heat. This heat may be generated using an oven in a batch or continuous mode, or by a heat gun or lamp, alternatively using an oven. The composition should be heated to a temperature allowing for cure. Alternatively, the composition should be heated to a temperature greater than 9O ⁰ C for greater than 40 minutes, alternatively greater than 14O ⁰ C for greater than 15 minutes, alternatively greater than 16O ⁰ C for greater than 10 minutes.

[0032] Other embodiments of the invention relate to the curable compositions prepared by the methods described above.

[0033] The coating compositions of this invention are useful as a stand-alone coating or as ingredients in protective coatings, paint formulations, and powder coatings. Applications such as automotive top coats, electronics packaging, and specialty adhesives prefer a one-part delivery to avoid poor performance due to formulating and mixing issues at the application site. The coating compositions of this invention can also be formulated with a blowing agent and cell stabilizer to produce thermally stable foam formulations or used as an adhesive formulation by applying to one or both substrates and mating the substrates. EXAMPLES

Preparation of Carbinol-functional Silicone Resin A: M ^PrOH o. ₃₅ T ^Me o. ₃ T ^Ph oj [0034] 2379.5g Phenyltrimethoxysilane and 1634.6g methyltrimethoxysilane, were catalyzed by 2.3g trifluoromethane sulfonic acid (TFMSA), and then were hydrolyzed with 500.9g deionized water, followed by distillative removal of by-product methanol. 1316.4g of l,l,3,3-tetramethyl-l,3-disiloxane (TMDS), and 588.6g acetic acid, were added, and the mixture was heated to 50 ⁰ C for three hours. Methanol and methyl acetate were removed via distillation. 1800g of heptane was added, and the mixture was washed with (i) saturated aqueous sodium bicarbonate and (ii) multiple aliquots of deionized water. The mixture was then filtered, and the solvent was removed as needed by distillation yielding 3385g of M^0.393T^ ^e 0.304T^ ⁿ 0.303 SiH functional intermediate resin (M^ denotes H(CHs) ₂ SiOy ₂ , T ^Me denotes CH ₃ Si0 ₃ / ₂ , and T ^ph denotes C ₆ H ₅ Si0 ₃ / ₂ .

Then, 249.9g of this SiH functional silicone resin M^Q 393T^ ^e o .304^^0 303 was dissolved in 250g xylene and heated to 70-95 °C. A catalytic amount (1.8g) of 1 percent by weight of Pt(Al2θ3) was added, followed by the addition of 196.5g allyl alcohol. The mixture was heated at 70-110 ⁰ C until the SiH was consumed, as determined by following the disappearance of its peak in the FTIR spectrum at about 2165 cm"l Triphenylphosphine and carbon black were added as needed. The product mixture was filtered, and the solvent was removed to yield 301.9g Carbinol-functional Silicone Resin A having the units _M PrOH _{Q 35} χMe _{0 3} χPh _{0 3 M} PrOH denotes (HO(CH ₂ )3)(CH ₃ )2SiOi/2, T ^ph denotes

C ₆ H ₅ Siθ3/2 ₅ T ^Me denotes CH ₃ Siθ3/2 ₅ and the allyl alcohol is CH ₂ =CHCH ₂ OH.

Preparation of Carbinol-functional Silicone Resin B: Q ₀₂

[0035] A 4 neck 3L round bottom flask was loaded with 787.8Og of PhSi(OMe) ₃ and 390.29g of Nissan IPA-ST colloidal silica (Nissan Chemical (Houston, TX) . The flask was equipped with an air driven teflon stir blade, thermometer, and a water-cooled condenser. 171.79g of deionized water containing 0.38g of concentrated HCl was added to the flask and the mixture was heated to reflux following a brief exotherm. 90Og of room temperature toluene was added followed by 266.7g of l,l,3,3-tetramethyl-l,3-disiloxane (TMDS) and 1.26g trifluoromethane sulfonic acid (TFMSA). The reaction mixture was heated to 65 ⁰ C for three hours followed by distilling off methanol and isopropanol volatiles at 75 ⁰ C. The reaction mixture was cooled to 4OC and 8.4g calcium carbonate was added to neutralize the sulfonic acid catalyst. The mixture was then filtered, and the solvent was removed as needed by distillation yielding 1509g of SiH functional intermediate resin in toluene solution at 50% solids [0036] The SiH functional silicone resin solution was heated to 95C. A catalytic amount (3.0g) of 1 percent by weight of Pt(Al2θ3) was added, followed by the addition of 692.1g allyl alcohol. The mixture was heated at 70-110 °C until the SiH was consumed, as determined by following the disappearance of its peak in the FTIR spectrum at about 2165 cm ^~ l. Triphenylphosphine and carbon black were added as needed. The product mixture was filtered, and the solvent was removed to yield 1002.5g of Carbinol-functional Silicone Resin B having the units

_M PrOH _{0 4T} Ph _{0 4} Q ₀₂ (MPrOH denotes (HO(CH ₂ )3)(CH ₃ ) ₂ SiO ₁ /2, T?h denotes C6H5Siθ3/2 ₅ Q denotes Siθ4/2

[0037] Blocked Isocyanate 1: Tolonate® D2Methylethyl ketoxime blocked hexamethylene diisocyanate (Equivalent weight 370 g/mol blocked isocyanate (75% solids in aromatic solvent) (Rhodia, Cranbury,NJ)

[0038] Isocyanate 1: Tolonate® HDT-LV hexamethylene diisocyanate trimer (Equivalent weight 183 g/mol isocyanate (Rhodia, Cranbury,NJ)

[0039] Polyol 1: Desmophen® 870 BA is a hydroxyl-functional polyacrylate resin supplied in butyl acetate (70% solids, Equivalent weight 576g/mol carbon-bonded hydroxyl) by Bayer Corporation (Pittsburgh, PA). -

Test Methods:

[0040] 60° GLOSS: (ASTM D523-89) Measured gloss ratings was obtained by comparing the specular reflectance from the sample to that from a black glass standard. Sixty-degree gloss is used for comparing most samples. Testing was performed using a Gloss-meter (BYK-Gardner Micro-Tri-gloss, Catalog #4522). A minimum of five readings were taken on the coating surface and the average was reported with higher values indicating smoother and more reflective coatings. [0041] PENCIL HARDNESS: (ASTM D3363) Coatings were rated by attempting to scratch the surface with drafting pencils of increasing lead hardness. Coating hardness was rated as the highest lead hardness that cannot scratch through the coating. [0042] GARDNER REVERSE IMPACT TEST: (ASTM D2794) 1.8 kg shaft with 1.3 cm rounded tip is dropped up to 35.6 cm onto the test panel, which is placed at the base. The test panel was extruded into a 1.6 cm diameter convex half sphere in the base. Coating failure occured when crazing is detected. A value of zero indicates that coating failure occurred even at the lowest drop height, whereas a value of 30 indicated that failure did not occur when the maximum drop height was utilized. [0043] THERMOGRAVIMETRIC ANALYSIS Thermogravimetric analysis was performed using a TA Instruments (New Castle, DE) TGA 2950. Approximately 7 to 12 mg of a single piece of the test specimen was placed in a Pt pan

and heated to 1000 ⁰ C at 10°C/min under a N ₂ atmosphere and the weight loss continuously monitored and recorded. Similar tests were also performed up to 500 ⁰ C under an air and N ₂ atmosphere. The weight loss at 500 ⁰ C in air and 500 ⁰ C and 1000 ⁰ C in N ₂ was reported in Table 2. The uncertainty was estimated to be ±5% based on duplicate analysis.

[0044] Control 1: Using Blocked Isocyanate 1, as depicted in Table 1, a one-part urethane formulation was prepared by blending the blocked isocyanate at a 10% excess (relative to stoichiometry- so mole of blocked isocyanate to carbon-bonded hydroxyl is 1.1:1) with Polyol 1 , as depicted in Table 1 to make a urethane coating [0045] Control 2: A one-part urethane coating formulation was prepared using a standard isocyanate (Isocyanate 1) and a carbinol functional silicone as depicted in Table 1, at 10% excess isocyanate for comparison. This formulation is not viable for a one-part delivery as the solution gelled within 7 hours. Examples 1-2: One-Part Urethane Coating Formulations and preparation of coatings and monoliths therefrom.

[0046] One-part urethane formulations were prepared by blending the blocked isocyanate at a 10% excess (relative to stoichiometry) with a carbinol functional siloxane or organic polyol as depicted in Table 1. [0047] For the Controls and Examples 1 and 2, each one part formulation was evaluated in three different configurations 1)0.003 in draw down coating on an aluminum panel and cured, 2) poured as 3mm thick layer in an aluminum pan mold and cured into a monolith and evaluated for appearance and high temperature weight loss in air and N2 environments 3) poured into a capped vial and evaluated over time for viscosity changes to check 1-part storage viability. The appearance and tactile observations of the formulations and cured materials are shown in Table 1. Table 2 displays the coating properties and the monolith thermal stability properties of the cured materials.

Table 1 One-Part Urethane Formulations and Performance Observations

<_*

*cured 2 hr at 150C in air

+ cured in air 1 hr 7OC then lhr IOOC then lhr 150C. # yes (no visible sign of viscosity drift in sealed vial for >2 months)

Table 2: Coating Properties and Thermal Stability of One Part Formulations

[0048] The one-part urethanes using a carbinol silicone resin have comparable coating properties to the Control 1 but these coatings exhibit some significant benefits in impact resistance. In addition, urethanes using a carbinol silicone resin have superior weight retention at elevated temperatures relative to its organic analog (Control 1).