HK1028979B - Powder coatings or adhesives employing silanes or silane treated fillers - Google Patents

Description

Powder coatings or adhesives using silane or silane-treated fillers

Field of the invention

The present invention pertains to powder coating and adhesive formulations using organosilane compounds or their hydrolysates or condensates as crosslinking agents and/or adhesion promoters.

Background of the invention

Powder coatings are environmentally friendly systems, which makes them ideal replacements for traditional solvent-based coating systems. Overall, its operating and material costs can be favorably competitive with solvent and water-based systems.

Although powder coatings represent only a portion of the market share compared to solvent-based systems, this technique has considerable advantages. Most notably, since powder coatings are solvent free, no Volatile Organic Compound (VOC) issues need to be considered. In addition, powder coating technology has less environmental impact due to less waste generated.

The manufacture of powder coatings involves several steps, the most critical of which is the pre-mixing of the ingredients. In this initial stage, the binder, together with other additives, is thoroughly mixed in the apparatus. Insufficient premixing in the first stage can result in the coating being a non-uniform composition and resulting in poor mechanical properties or surface defects in the final product. The formed premix is then fed to an extruder. The molten material emerging from the extruder is cooled and extruded into a ribbon which is easily broken. The sliver is then ground into particles of a particular size range.

The most common method of applying powder coatings is electrostatic spraying. The basic principle of this method involves pushing the powder out by compressed air through the spray gun where it becomes electrostatically charged. In addition to charging the powder, the spray gun is also used to deposit the powder supplied by the feeder. When the electric field is removed, the charged particles remain on the surface and are attracted by the charge on the substrate. Uncharged powder outside the spray range was collected and reused.

Another common method of powder coating is triboelectric spraying. It is similar to electrostatic spraying except that the particles are positively charged (electrostatically charged particles have a negative charge). A new technology developed for flat surfaces is the use of electromagnetic brushes that can apply very thin coatings at sufficiently high speeds without repetition.

A disadvantage of thermosetting powder coating systems is that it is difficult to form a tough film from low molecular weight ingredients, so that it flows easily under shear conditions. Since the application of powder coatings includes overspray, special recycling equipment is also required to recover the unused powder. The substrate must also be able to withstand the curing temperatures of powder coatings, typically 150 ℃ and 190 ℃.

The physical and chemical properties of thermoplastic powder coatings can advantageously be improved with the silanes of the invention. These powder coating formulations do not require curing agents and can be applied by the electrostatic or triboelectrostatic spraying techniques described above. However, most thermoplastic powders are carried out by passing the heated substrate through a fluidized bed.

Silanes are known to be useful in liquid coatings. For example, in WO96/39468, sprayable liquid coating compositions are described comprising a film-forming compound containing reactive silyl groups and polymeric microparticles that are insoluble in the liquid coating composition.

Summary of the invention

One aspect of the present invention is a powder coating or adhesive formulation comprising ingredient (a): at least one silane of the formula (I),

or a hydrolysate or condensate of such a silane, wherein R¹Is a hydrocarbyl, acyl, alkylsilyl or alkoxysilyl group, R²Is a monovalent hydrocarbon radical, R³Is alkylene, optionally interrupted by one or more ether oxygen atoms, a is 0 or 1, Z is a direct bond or a divalent organic linking group, X is a monovalent organic group or H, m is 1 to 20; and (B) at least one organic resin component.

One embodiment of the present invention is a powder coating or adhesive formulation as described above, wherein the silane has the following structural formula:

wherein A and B are independently-NH-or-O-, R¹、R²、R³And a and m are as defined above. In some embodiments, the silane is a carbamate compound of formula II, i.e., one of a and B is NH and the other is O.

In a preferred embodiment of the invention, there is provided a powder coating or adhesive formulation comprising: (A) at least one silane of formula a, or a hydrolysate or condensate of the silane:

in the formula R¹Is C₁-C₆Alkyl radical, R³Is C₂-C₆Alkylene, one of A and B being NH and the other being an oxygen atom, X being C₄-C₁₂Straight, branched or cyclic alkyl, m is 1-4; and (B) at least one organic resin component selected from polyesters.

The silane carbamate compound of formula II having a melting point of about 30-170℃ forms another aspect of the present invention.

Silanes useful in the present invention can be prepared by a number of synthetic routes. For example, terminally unsaturated organic compounds can be hydrosilylated to produce silanes. Further chemical reactions can be carried out on the silane having an organofunctional group. The silyl carbamate useful in the present invention can be obtained by reacting a polyol compound with an isocyanatopolyalkoxysilane. Other carbamates useful in the present invention can be prepared by the reaction of a polyisocyanate with a hydroxyalkyl polyalkoxysilane. Such silyl carbamates can also be prepared by the reaction of a polyisocyanate with a terminally unsaturated alcohol, and the subsequent hydrosilylation reaction of the reaction product thereof. The silyl isocyanate can oligomerize: yielding a nitroxymethyl polyester, allophanate, biuret, isocyanurate. The silylamines can react with anhydrides to form amides, or with isocyanates to form ureas.

The powder coating or adhesive of the invention may be based on conventional resin systems. In such coatings, the silane component of formula I is used as a performance modifier and/or crosslinking additive. Silane compounds of formula I (where m is greater than 1, especially those where X is a polymer) can be used as the primary crosslinking resin in the present coating formulation.

The silane may be coupled to a filler or pigment. This is accomplished by way of a hydrolysis or condensation reaction mechanism in which the silane compound actually reacts with the filler or pigment. Powder coatings using fillers or pigments so treated also form a further aspect of the invention. Preferred such fillers or pigments are those in which the silane has alkyl, epoxy, acryl, methacryl, anhydride, polyether, hydroxyalkyl or amino (especially primary or secondary amine) groups thereon, or the silane has the formula II. By silanes of the formula II or III

Q-R³-Si(OR¹)_aR² _3-a III

Treated novel TiO₂Filler, constituting a further aspect of the invention, the silane formula wherein Q is a monovalent organic group having at least one epoxy, amine, methacryloyl, acryloyl, anhydride or hydroxyalkyl functionality, R¹、R²、R³Is as defined above. The novel fillers and pigments treated with silanes of formula II form a further aspect of the invention.

Detailed description of the invention

Powder coating systems may be based on organic resin systems including thermoplastic and thermosetting materials. The term "resin" as used in the present technology refers to a fixable material. Thermoplastic materials are resins because they can be set from the molten state. Thermosets are often referred to as resins, whether they are polymers, prepolymers, or monomers in their state. Herein, the term "resin" includes both thermoplastic polymers and thermoset materials.

Powder coating systems can be based on a number of thermosetting chemicals. Known powder coating systems include polyurethane systems based on blocked polyisocyanates and polyol compounds, especially polyester or poly (meth) acrylate polyols; acid functional acrylic or other acid functional polymers cured with epoxy functional curing agents; anhydride/epoxy systems; an epoxy/polyol system; a hybrid system of epoxide resin and polyester with both carboxyl and hydroxyl functions is used; a system based on a hydroxyalkyl amide and an acid functional polymer. Examples of suitable epoxy resins include bisphenol a type polyepoxides, glycidyl methacrylate copolymers, and epoxy-phenolic resins. While in some cases uv curing systems may be used to separate the film-forming melt flow stage from the curing stage, typically the system is designed such that melt flow and curing occur simultaneously in one heating step.

Specific powder coating systems in which the compounds of the present invention are employed include polyester-urethane powder coatings in which a hydroxy-functional polyester resin is cured with a polyisocyanate. The polyisocyanates are internally blocked or blocked with blocking agents. The primary capping agent is emulsion caprolactam. When the powder coated parts are heated, the emulsion caprolactam volatilizes and the isocyanate groups deblock, leaving them free to react with the hydroxyl functions on the polyester resin. The most commonly used blocked isocyanates are caprolactam-blocked IPDI (isophorone diisocyanate), for example Huls Vestagon B1530. Polyisocyanates can be internally blocked by a self-condensation process to form a nitroxymethyl polyester. One such commercially available nitroxymethyl polyester compound is HulsVestagon BF 1540 (an IPDI nitroxymethyl polyester).

Hydroxy-functional polyester resins, which are commonly used in polyester-polyurethane systems, result from the polycondensation reaction of a diol, a dicarboxylic acid, and a polyol compound (the monomer contains more than two hydroxyl groups). Diols frequently used are trimethylpentanediol and neopentyl glycol; the polyol compounds include trimethylolpropane and trimethylolethane. The dibasic acids include isophthalic acid and terephthalic acid. Reaction details of standard methods for preparing hydroxy-functional polyester resins for polyurethane powder coatings are described in the book by Oldering and Hayward (Oldering p. and Hayward g., resins for surface coatings, second volume, p 137, published by SITA Technology of london in 1987). Different patents describe processes for making hydroxy-functional polyester resins for polyurethane powder coatings with minor variations in acid number, hydroxyl number, functionality of the resin, and choice of raw materials. The hydroxy-functional polyesters used in powder coatings can have an acid number of less than 10, a molecular weight of 2800-3200, a hydroxyl number of 84 and a softening point of 95-100 ℃.

A typical IPDI crosslinked powder coating composition is as follows: 52-53% of hydroxyl polyester, 12-13% of IPDI cross-linking agent, 34% of pigment filler, 1% of flow regulator and small amount of other ingredients.

Other powder coatings in which the silane compounds of the present invention are useful are acrylic-urethane powder coatings. In such systems, hydroxy-functional acrylic resins are used to prepare acrylic-urethane powders in a manner substantially similar to polyester-urethane. Hydroxy-functional acrylic resins can be made as copolymers of methyl acrylate, styrene, acrylic esters, hydroxyethyl methacrylate and acrylic acid. About 9-10% hydroxyethyl methacrylate is typically required to produce a resin with a hydroxyl number of 40, and about 2% acrylic acid to an acid number of 16. Methyl methacrylate and styrene copolymers produce a high Tg (e.g. 95-105 ℃) and are typically toughened with longer chain acrylates or methacrylates such as butyl, ethyl or 2-ethylhexyl esters. Butyl acrylate is often preferred as the acrylic comonomer because of its excellent uv light resistance and high flexibility. The molecular weight of the acrylic copolymer resin is usually 5000-.

The formulation of the acrylic-urethane powder coating is similar to the polyester-urethane formulation except that acrylic resin is used instead of polyester resin.

Still other powder coating formulations in which the silane compounds of the present invention may be used are based on glycidyl-functional acrylate resins, especially glycidyl methacrylate copolymers, and compounds bearing two or more carboxylic acid groups, such as dodecanedioic acid. An exemplary glycidyl methacrylate copolymer is made from 15-35% by weight glycidyl methacrylate, 5-15% by weight butyl methacrylate and the balance styrene and/or methyl methacrylate, and has a number average molecular weight of less than 2500, a Tg of greater than 80 ℃, and a melt viscosity of less than 400 poise (40 Pascal sec) at 150 ℃.

The silane compounds of the present invention can also be used in TGIC/polyester powder coating systems. In such systems, the carboxyl functional polyester resin is cured using TGIC (triglycidyl isocyanurate). Polyester resins suitable for powder coatings using TGIC in the formulation are described in DSM resin BV (DSM resin BV, Belgian patent 898,099, 1982). The resin is obtained from the melt esterification of neopentyl glycol, 1, 4-cyclohexanedimethanol, 1, 6-hexanediol, trimethylolpropane, terephthalic acid and adipic acid. The products obtained have an average molecular weight of 4500-12500, an acid number of 10-26 mg KOH/g and a Tg of 40-85 ℃ and are suitable for the production of powder coatings containing 1.4-5.3% by weight of TGIC. The silanes of the present invention can also be used with similar carboxyl functional polyesters cured with hydroxyalkyl amides.

The powder coating formulations of the present invention may also be based on thermoplastic polymers such as nylon, polyolefins (e.g., polypropylene and polyethylene), polyphenylene sulfide or polyvinyl chloride.

The softening point of the matrix component of the powder coating composition is such that the additives necessary to make the coating formulation of the present invention function at temperatures of about 80-140 c and produce a composition that can be subsequently extruded and ground to a free-flowing fine powder having a size of about 20-120 microns. Solid additives that melt and are compatible with the formulation are preferred. However, compatible liquids can be used either through the masterbatch or on an inert carrier.

In one aspect of the invention, a powder coating or powder binder composition includes a powder coating or powder binder having the structural formula I:

the silane compound (a) of (b),or a hydrolysate or condensate of such a silane compound, wherein R¹Is a hydrocarbyl, acyl, alkylsilyl or alkoxysilyl group, R²Is a monovalent hydrocarbon radical, R³Is an alkylene group, optionally interrupted by one or more ether oxygen atoms, a is 0 or 1, Z is a direct bond or a divalent organic bonding group, X is a monovalent organic group or H, m is 1 to 20, the number m is preferably 2 to 6, most preferably 2.

Radical R¹Can be an alkyl, aryl, alkaryl, aralkyl or acyl group, for example methyl, ethyl, n-propyl, isopropyl, butyl, tert-butyl, phenyl, benzyl, tolyl, benzoyl or acetyl. R¹It may also be an alkylsilyl group, for example a trialkylsilyl group such as trimethylsilyl, triethylsilyl or tripropylsilyl or an arylalkyldialkylsilyl group such as benzyldimethylsilyl or tolyldimethylsilyl. R¹May also be an alkoxysilyl group, for example a trialkoxysilyl group such as trimethoxysilyl, triethoxysilyl and tripropoxysilyl; alkyldialkoxysilyl groups such as methyldimethoxysilyl group, methyldiethoxysilyl group, ethyldimethoxysilyl group, ethyldiethoxysilyl group, methyldiprethoxysilyl group and ethyldipropoxysilyl group; or dialkylalkoxysilyl groups such as dimethylmethoxysilyl, dimethylethoxysilyl, dimethylpropoxysilyl, diethylmethoxysilyl, diethylethoxysilyl and diethylpropoxysilyl. R¹Preferably linear, branched or cyclic C₁_C₆An alkyl group or an acetyl group. Most preferred is ethyl or methyl. Suitable R²The hydrocarbon radicals being aryl, alkenyl or alkyl radicals, which may be linear, branched or cyclic, and are particularly lower (C)₁_C₄) Alkyl groups such as methyl or ethyl. Suitable R³Is C₂_C₁₂Linear, branched or cycloalkylene, preferably C₂_C₆An alkylene group. Exemplary R³The radical being aPropyl, ethylcyclohexylene, 3-dimethylbutylene, ethylene and methylene.

Z is a direct bond or a divalent organic bonding group, suitable divalent bonding groups include esters, amides, ureas, azomethides, urethanes, carbonates, aromatic rings, heterocycles, allophanates, biurets, amines, ethers, and thioethers. The Z groups may be the same or different.

The monovalent organic group X is typically the residue of an organic compound bearing one or more carboxylic acids, halides, alcohols, isocyanates, amines, epoxies, thiols, or other pendant or terminal functional groups that have been reacted in a known manner to form the linkage Z. The residue X can be a polymer, such as a polyacrylate, a polycarbonate, a polyurethane, a polyalkylene, a polyester, a polyamide, a polyether, and combinations thereof. The radical X is preferably an aliphatic, cycloaliphatic or aromatic hydrocarbon radical, preferably C₁_C₂₄Hydrocarbon groups, especially saturated linear, branched or alicyclic hydrocarbon groups. Exemplary X groups include 2, 3-butylene, 1, 6-hexylene, 1, 4-cyclohexanedimethylene, 1, 4-cyclohexylene, 1, 7-heptylene, 1, 8-octylene, 1, 12-dodecylene, 1, 10-decaalkylene, 1, 9-nonylene, 4 '-isopropylidenediphenylene, 4' -isopropylidenedicyclohexylene, 1, 4-butylene, phenylene, methylphenylene, 1,3- (. alpha.,. tetramethyl) xylylene.

If m ═ 1, then z is preferably a direct bond and x is preferably an alkyl group or a group with epoxide, methacrylate, acrylate or amine functionality. The alkyl groups may be linear or branched. If it is an alkyl group, the alkyl group should be C₄_C₁₈More preferably C₆_C₁₂Most preferably C₈。

Preferred silanes useful in the formulations of the present invention can be characterized by structural formula II:

or a hydrolysate or condensate of the formula wherein R¹、R²、R³A, m and X are as defined above, A and B are independently-NH-or-O-.

Silyl carbamates of formula II wherein a ═ NH and B ═ O can be prepared by the reaction of polyol compounds with isocyanatoalkylalkoxysilanes. The novel silane carbamates obtainable in this way include the carbamates formed wherein the polyol compound is a dialkanol. Linear symmetrical diols such as 1, 4-cyclohexanediol, 4' -isopropylidenedicyclohexanol and 1, 4-cyclohexanedimethanol also yield the preferred silyl carbamate compounds of the invention. Silyl carbamates of this type can also be prepared by reacting silyl isocyanates with polymeric polyol compounds such as polyether polyol compounds, polyester polyol compounds, polybutadiene polyol compounds or polyacrylate polyol compounds.

Suitable examples of isocyanatoalkylalkoxysilanes are isocyanatopropyltrimethoxysilane, isocyanatopropylmethyldimethoxysilane, isocyanatopropylmethyldiethoxysilane, isocyanatopropyltriethoxysilane, isocyanatopropyltriisopropoxysilane, isocyanatopropylmethyldiisopropoxysilane, isocyanatoneohexyltrimethoxysilane, isocyanatoneohexyldimethoxysilane, isocyanatoneohexyldiethoxysilane, isocyanato neohexyl triethoxysilane, isocyanato neohexyl triisopropoxysilane, isocyanato neohexyl diisopropoxysilane, isocyanato isopentyl trimethoxysilane, isocyanato isopentyl dimethoxysilane, isocyanato isopentyl methyldiethoxysilane, isocyanato isopentyl triethoxysilane, isocyanato isopentyl triisopropoxysilane, and isocyanato isopentyl methyldiisopropoxysilane.

Suitable examples of polyol compounds which will react with the isocyanatoalkylalkoxysilane to form solid silyl carbamate esters include 2, 3-butanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, 1, 4-cyclohexanediol, 1, 7-heptanediol, 1, 8-octanediol, pentaerythritol, 1, 12-dodecanediol, 1, 10-decanediol, 3, 6-dimethyl-4-octyne-3, 6-diol, 1, 9-nonanediol, bisphenol A, hydrogenated bisphenol A (i.e., 4' -isopropylidenebicyclohexanol), and 1, 4-butanediol.

The reaction product of the polyol compound and the isocyanatopropyltrialkoxysilane can be a liquid or a solid of various viscosities at room temperature. Solids having melting points of about 30-170 c are particularly suitable for use as powder coating additives since they can be added directly to conventional compositions without substantially changing their melt properties.

The isocyanatopropylalkoxysilane preferably has a high purity, i.e., greater than about 95%, and is preferably free of impurities and/or additives such as transesterification catalysts which promote side reactions. Examples of undesirable transesterification catalysts are acids, bases, organometallic compounds. For isocyanatopropyltrimethoxysilane, a purity of at least 98% is preferred. This can be done by distillation under the reference SILQUEST^*Y-5187 silane is available as isocyanatopropyltrimethoxysilane from Witco Corporation to remove impurities such as (3-trimethoxysilylpropyl) methylcarbamate and others as well as inhibitors, catalysts, and other additives.

Preferred diols have symmetry, such as 1, 4-butanediol, 1, 4-cyclohexanediol and 1, 4-cyclohexanedimethanol. While the reaction product of 1, 4-butanediol and isocyanatopropyltriethoxysilane is a solid at room temperature, the reaction product of 1, 2-butanediol or 1, 3-butanediol with isocyanatopropyltriethoxysilane is a liquid at room temperature. Similarly, the reaction product of 1, 4-cyclohexanediol and isocyanatopropyltriethoxysilane is a solid at room temperature, while the reaction product of 1, 2-cyclohexanediol and isocyanatopropyltriethoxysilane is a liquid at room temperature. A schematic reaction for the formation of a silane carbamate from a diol is illustrated below:

wherein R is³And X is as defined above. The reaction is catalyzed by tin catalysts such as dibutyltin dilaurate (DBTDL), dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin dioctoate, dibutyltin bis (2-ethylhexanoate), tin acetate, tin octoate, tin ethylhexanoate, tin laurate. Other urethane catalysts include: K-KAT^*s (zirconium, aluminium, bismuth compounds), diazabicyclo [2, 2]Octane (DABCO), N-Dimethylcyclohexylamine (DMCA), 1, 8-diazabicyclo [5, 4,0]-undec-7-ene (DBU), 1, 5-diazabicyclo [2, 3, 0]Non-5-ene (DBN). The reaction is usually exothermic and the temperature should be controlled to minimize the color of the final product. Excessive exothermicity may also introduce impurities by side reactions. It is recommended that the exotherm be controlled so that the temperature of the reaction mixture does not exceed 150 c, more preferably does not exceed about 110 c.

In a similar manner, triols, tetrols, pentols, hexals can be reacted with an equivalent amount of isocyanatoalkyltriethoxysilane. Such materials include glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, inositol, mannitol, sorbitol, fructose, fucose and glucose.

The preferred silane of the present invention is an addition compound prepared from 2 moles of isocyanatopropyltriethoxysilane with 1 mole of 1, 4-cyclohexanedimethanol.

Examples of such carbamates include: bis [3- (triethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate, bis [3- (trimethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate, bis [3- (methyldimethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate, bis [3- (triethoxysilyl) propyl ] -1, 2-cyclohexanedimethyldicarbamate, bis [3- (methyldiethoxysilyl) propyl ] -1, 2-cyclohexanedimethyldicarbamate, bis [3- (triethoxysilyl) propyl ] -1, 4-butanedicarbamate, bis [3- (methyldiethoxysilyl) propyl ] -1, 4-butanedicarbamate, bis [3- (triethoxysilyl) propyl ] -2, 3-butanedicarbamate, bis [3- (triethoxysilyl) propyl ] -1, 10-decanedicarboxylate, bis [3- (trimethoxysilyl) propyl ] -1, 6-cyclohexanedicarbamate, tris [3- (trimethoxysilyl) propyl ] -1, 2, 3-propanetricarbamate, tris [3- (triethoxysilyl) propyl ] -1, 2, 3-propanetricarbamate, tris [3- (methyldimethoxysilyl) propyl ] -1, 2, 3-propanetricarbamate.

Other silyl carbamates of formula II, wherein a ═ O and B ═ NH, can be prepared from the reaction of alkoxysilyl alcohols with polyisocyanates. Such silyl carbamates may also be obtained by reaction of a polyisocyanate with a terminally unsaturated alcohol followed by hydrosilylation.

A schematic reaction for the preparation of silyl carbamates from diisocyanates and alkoxysilyl alcohols is illustrated below:

wherein R is³And X is as defined above. This reaction can be integrated by the above-mentioned catalyst, and the same applies. Preferred X (N ═ C ═ O)_nThe compounds are polyisocyanate prepolymers prepared from diisocyanates and polyol compounds. In a similar manner, triisocyanates such as IPDI isocyanurate and HDI isocyanurate can be reacted with an equivalent amount of alkoxysilyl alcohol. The alkoxysilyl polyol compound can be reacted with an equivalent amount of polyisocyanate in this reaction.

Suitable examples of alkoxysilyl alcohols include: carbamic acid N (3-methyldiethoxysilylpropyl) -2-hydroxy-1-propylEsters, N (3-methyldiethoxysilylpropyl) -1-hydroxy-1-propyl carbamate, N (3-triethoxysilylpropyl) -2-hydroxy-1-propyl carbamate, N (3-triethoxysilylpropyl) -1-hydroxy-1-propyl carbamate, N (3-triethoxysilylpropyl) -4-hydroxybutyramide. Other examples are described in us patent 5,587,502, the contents of which are incorporated herein by reference. Suitable polyisocyanates include, but are not limited to: 1, 6-Hexane Diisocyanate (HDI), isophorone diisocyanate (IPDI), 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, a mixture of 2, 4-toluene diisocyanate and 2, 6-Toluene Diisocyanate (TDI), diphenylmethane 4, 4-diisocyanate (MDI), bis (4-isocyanatocyclohexyl) methane (H)₁₂MDI), 1,3- (α, α, α ', α', -tetramethyl) xylene diisocyanate (TXMDI), α, α -dimethyl m-isopropylbenzyl isocyanate (m-TMI), and dimers, trimers, biurets, allophanates, and other oligomers of such polyisocyanates. The polyisocyanate may also be a polymeric polyurethane "prepolymer", such as those obtained by the reaction of the above-mentioned polyisocyanate and a polyether polyol compound, a polyester polyol compound, a polybutadiene polyol compound or a polyacrylate polyol compound.

Alternatively, the carbamates useful in the present invention may be prepared by reacting a terminally unsaturated alcohol with a polyisocyanate and hydrosilylation of the terminally unsaturated polyurethane intermediate in the presence of a suitable catalyst. An example of a reaction sequence using allyl alcohol and a platinum catalyst is illustrated below:

wherein R is¹And R²X is an organic radical and n is 1 to 10. For example isocyanates OCN-X- (NCO)_nCan be HDI, IPDI, H₁₂MDI, TDI, MDI, TMXDI, TMI or prepolymers of dimers, trimers, allophanates or oligomers thereof. In the above sequence as wellInstead of allyl alcohol, a terminally unsaturated polymeric alcohol may be used. These and other contents of U.S. patents 5,298,572 and 5,227,434 (to which reference is made) are incorporated herein by reference. Similarly, a terminally unsaturated isocyanate can be reacted with a polyol compound to give a terminally unsaturated urethane, which can be hydrosilylated in a similar manner:

silane urea compounds may also be used in the formulations of the present invention. Such compounds correspond to formula II, wherein a and B are both NH. They are suitable for being obtained by reaction of alkoxysilylalkylamines with organic isocyanates or by reaction of organic amines with alkoxysilylalkyl isocyanates. This reaction is similar to the reaction of isocyanates and alcohols, but generally does not require a catalyst.

Examples of alkoxysilylalkylamines include 3-aminopropyltriethoxysilane (SILQUEST)^*A-1100), 3-aminopropyltrimethoxysilane (SILQUEST)^*A-1110), 3-phenylaminopropyltrimethoxysilane (SILQUEST)^*Y-9669), N-bis (3-propyltrimethoxysilyl) amine (SILQUEST)^*A-1170), 3-aminopropyl (methyldiethoxysilane), 3-aminopropyl (methyldimethoxysilane), aminohexyltriethoxysilane (SILQUEST)^* Y-11637)。

Examples of the organic (poly) amine include: n-octylamine, n-hexylamine, ethylenediamine, propylenediamine, 1, 4-diaminobutane, 1, 6-diaminohexane, IPDA, TDA, MDA, H₁₂MDA. The organic amines may be polymers, such as Jeffamines^*(polyether polyamine).

In all of the above descriptions of synthetic methods, it will be understood that if the trialkoxysilane starting compound is replaced by the corresponding dialkoxyalkylsilane, triacyloxysilane, or diacyloxyalkylsilane, other compounds of formula I will be produced.

In addition, other conventional additives may be used. In a preferred process, a silicone slip agent is used in the extrusion.

Examples of conventional powder coating additives that may be added to the coating formulations of the present invention include: promoting catalysts, pigments, leveling agents, flow control agents, light stabilizers, antioxidants, and fillers, all of which are well known in the art. These ingredients may be used in the compositions of the present invention in conventional amounts.

Examples of suitable flow modifiers include, but are not limited to: acrylic resins (usually supported on silica), fluorinated aliphatic polyesters and polydimethylsiloxanes (preferably solid or high viscosity gels). Flow regulators are generally used in amounts of 0.5 to 2.0% by weight of the total composition.

In general, the titanium, zirconium or tin compound catalyst is added in an amount of usually 0.05 to 1.5%, preferably 0.1 to 0.5% by weight based on the total weight of the composition. Examples of these catalysts are dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dioxide, dibutyltin dioctoate, tin octoate, titanium isopropoxide, aluminum titanate, chelated titanic acid, zirconium ethoxide. Various tertiary amines and acids, alone or in combination, may be used to catalyze the curing of the silane. Other silane catalysts are described in U.S. patent 4923945, which is incorporated herein by reference.

Fillers and colorants can be added in large amounts, often 50% or more, sometimes 60% or more, by total weight of the composition. Fillers and pigments can be completely eliminated from the clear coat formulation.

The silane compounds described above are useful as crosslinkers, adhesion promoters, and/or modifiers of film properties such as environmental resistance or mar resistance. At the elevated temperatures used to cure the powder coatings, the urethane groups (if any) in the molecule can react with the isocyanate groups to form allophanates and biurets, and/or SiOR¹The groups are capable of reacting with the polyol compound in the coating in an exchange reaction.

The silanes of formula I may be used alone or in combination with conventional crosslinking agents. They may be used to provide a primary networking, or they may augment a conventional networking. In the case of compounds in which the X group is polymerizable and which are meltable solids, the silanes of formula I may be used as base resins for coating systems.

In addition to the above methods, the polymeric silanes of the present invention can be synthesized by the copolymerization of silane monomers with non-silane monomers. For example 3-methacryloxypropyltrimethoxysilane, SILQUEST^*A-174 may be added to an alkyl (meth) acrylate monomer such as methyl methacrylate (and/or a substituted (meth) acrylate such as hydroxyethyl acrylate, hydroxyethyl methacrylate, glycidyl acrylate, or glycidyl methacrylate) and copolymerized to give a silane-functional poly (meth) acrylate (or a silane-functionalized GMA resin if glycidyl methacrylate is included).

The silane compounds preferably used in the present invention are meltable solids, which makes them particularly suitable for incorporation into conventional powder coating formulations without substantially altering the melt properties of the material. It is desirable that the melting point be in the range of about 30-170 deg.C, preferably about 40-120 deg.C, and more preferably about 50-110 deg.C.

The molecular weight of the silane compounds of the present invention is preferably about 8000 daltons or less, more preferably about 5000 daltons or less.

Although solids are a preferred embodiment of the present invention, silanes in liquid form or waxy form can be used as additives in conventional powder coating resin systems.

The preferred way of adding the non-solid silane is through an inert carrier such as silica, carbon black or porous polymer. The liquid may also be added in the form of a solid solution, such as a "masterbatch" or capsule. The silanes of the present invention may be incorporated into powder coating formulations by blending into/onto pigments or fillers. Titanium dioxide is a preferred support for these silanes. These forms of silane can be added to powder coating formulations in a similar manner to solid silanes.

In typical powder coating formulations, the silanes are usefully incorporated in an amount of from about 0.5 to about 30% by weight of the formulation, more preferably from about 2 to about 10% by weight. However, in some formulations, higher or lower amounts may prove advantageous. Further, as described above, the silane compound of the structural formula I in which X is polymerizable can be used as the base resin. Accordingly, the powder coating formulations of the present invention should not be considered limited to these ranges of amounts.

Silanes having groups reactive with UV radiation, e.g. methacrylates (e.g. Silquest)^*A-174) can advantageously be used in combination with a uv radiation curable powder coating system, as shown, for example, in us patent 5,703,198. Epoxy-functional silanes (e.g. Silquest)^*A-187) can also be advantageously used in combination with a uv radiation curable powder coating system, as shown, for example, in us patent 5,789,039.

Powder adhesives may be similarly formulated. Such binders can be applied to one or both substrates to be bonded in the same manner as powder coatings, for example by electrostatic spraying, triboelectric spraying, electromagnetic brushing or by fluidized bed. The substrates are bonded by melting the coating by heating and, if not fully cured, allowed to cure. Once cooled, the adhesive assembly is completed. Typically, the size dispersion of such powder binders is such that at least 50% by weight will pass through a 200 mesh screen.

Yet another aspect of the present invention is a silane of formula I or a hydrolysate or condensate thereof wherein X contains an alkyl, epoxy, acrylate, methacrylate, anhydride, polyether, hydroxyalkyl or amino (especially primary or secondary amine) group or wherein the silane is a silane of formula II which is coupled to a filler or pigment such as titanium dioxide. In formula I, a suitable m is 1 for the filler. Mixtures of such silanes, especially those with alkylsilanes, may also be used. The product can be used as powder coating or powder adhesive additive.

Represented by formula II or by the following formula:

Q-R³-Si(OR¹)_aR² _3-asilane treated TiO of III₂Or pigments, constituting a further aspect of the invention, wherein Q in formula III is a monovalent organic group bearing at least one epoxide, amine, methacryl, acryloyl, anhydride, or hydroxyalkyl functionality, R¹、R²And R³Is as defined above.

The amine may be a primary, secondary or tertiary amine, and for secondary or tertiary amine groups, the alkyl side chain may be optionally substituted, for example with amino or hydroxyl groups. Specific examples of Q-R-groups include: glycidoxypropyl, 2- (3, 4-epoxycyclohexyl) ethyl, H₂N-(CH₂)₃-、H₂N-(CH₂)₃-NH-(CH₂)₂-, acryloyloxypropyl, methacryloyloxypropyl. Q preferably contains an epoxy group.

Silanes are typically coupled to fillers or pigments by hydrolysis or condensation reactions. The general procedure for treating fillers/pigments with silanes can be found in U.S. Pat. Nos. 4,061,503, 4,151,154, 5,057,151 and 5,562,990, and also the references identified therein. A long list of fillers/pigments that can be treated with silanes can be found in the above-mentioned patents, all of which are incorporated herein by reference. Silanes can be condensed onto various supports in amounts of 1-60%, depending on the nature of the support; titanium dioxide is able to carry less than about 20% silane and still retain a fine powder. For example, a suitable titanium dioxide can be treated with a solution of an epoxy-functional trialkoxysilane, optionally with a co-solvent and water (acidic pH about 2-5) in a high shear mixing device. Suitable solvents include, but are not limited to: THF, dioxane, methanol, ethanol, DMF, DMSO. The concentration of the epoxy-functional trialkoxysilane in solution is not critical, however, it is effective to minimize back-extraction of the solvent using concentrated solutions (60-90%). After removal of volatiles, the treated titanium dioxide can be added to powder coating formulations.

When a combination of various silanes is used, a synergistic effect can be achieved. The silanes on the above carriers may be added separately to the formulation or as a mixture. The mixture may be prepared in a mixing step, or during extrusion. These synergistic silane combinations can be used instead of conventional crosslinking systems such as TGIC or Primid^*XL-552. A variety of titanium dioxides may be used as supports for the silane including, but not limited to: tiona^*RCl-9、RCl-535、Kronos^*2020、Ti-Pure^*R-100 series, R-700 and R-900. Suitable silica supports include, but are not limited to: hubersorb^*600、Hi-Sil^*ABS、Zeosil^*1165MP。

In some cases, the powder coatings of the present invention are capable of further curing and/or faster curing by the action of moisture. Especially in catalytic systems, it is common that ambient moisture will eventually completely cure the silane that was not cured during the baking step. However, high humidity treatment, hot water, or steam may be advantageously employed to more quickly achieve full cure. Thus, embodiments of the present invention can be used to apply a powder coating to a heat-sensitive substrate. After spray application, the coated substrate is heated to just high enough temperature to achieve proper flow and leveling. At this lower temperature, crosslinking is very low, viscosity remains low, and flow/leveling can be improved. In the second step, a moisture curing system can be employed. Moisture curing at lower temperatures can be promoted by the addition of one or more of the above-mentioned silane curing catalysts.

The invention is further illustrated by the following non-limiting examples.

Example 1

The silane carbamate compound is prepared from isocyanatopropylThe reaction of a methyltrimethoxysilane with a polyol compound as set forth in Table I. The reaction was carried out using a 2: 1.05 molar ratio of isocyanatopropyltriethoxysilane to diol and 300-500ppm dibutyltin dilaurate (DBTDL) catalyst at a total weight of about 30 grams. A100 ml round bottom 3-neck flask was equipped with a magnetic stir bar and a thermometer on one side. The apparatus includes a heated sleeve with a calorimeter. TEFLON is used at the junction^*And (3) a lubricant. The ingredients were transferred into a flask, including a catalyst addition of 300-500ppm DBTDL. The flask was slowly heated under nitrogen until an exotherm occurred. The maximum temperature was maintained at about 100 ℃ to reduce the color of the final product. The reaction was controlled to proceed completely by the disappearance of NCO using IR. The appearance and viscosity of the product were recorded and if the product was a solid, the melting point was also determined by DSC (peak temperature). The product shape and melting point of the solid product are shown in table I.

TABLE I

Polyol compounds screened	Structure of polyol	Shape of the product	Melting Point (. degree.C.) of the product
				1, 2-octanediol	CH2(CH2)5CH(OH)CH2OH	Liquid, method for producing the same and use thereof
1, 4-cyclohexanediols	C6H10(OH)2	White hard block	63.1
				1, 12-dodecanediol	OH(CH2)12OH	Yellow wax	56.1
1, 10-decanediol	CH3(CH2)7CH(OH)CH2OH	White waxy solid	48.0
				1, 2-butanediol	CH3CH2CH(OH)CH2OH	Light yellow liquid
1, 3-propanediol	HO(CH2)3OH	Light yellow liquid
				1, 5-pentanediol	HO(CH2)5OH	Light yellow liquid
1, 3-butanediol	CH3CH(OH)CH2CH2OH	Yellow liquid
				1, 6-hexanediol	HO(CH2)6OH	White waxy solid	63.3
1, 7-heptanediol	HO(CH2)7OH	Solid body	51.1
				1, 8-octanediol	HO(CH2)8OH	Solid body	58.9
1, 9-nonanediol	HO(CH2)9OH	White waxy solid	38.8
				2, 2-dimethyl-1, 3-propanediol	HOCH2C(CH3)2CH2CH2OH	Light yellow liquid
2, 3-butanediol	CH3CH(OH)CH(OH)CH3	Pale yellow waxy solid	75
				2-ethyl-2- (hydroxymethyl) 1, 3-propanediol	C2H5C(CH2OH)3	Light yellow liquid
3-dimethyl-4-octyne-3, 6-diol	C2H5C(CH3)(OH)C＝CC(CH3)(OH)C2H5	White waxy solid	73.6
				3-cyclohexene-1, 1-dimethanol	C6H9CH2OH	Dark yellow liquid
Bisphenol A	(CH3)2C(C6H4OH)2	Pale yellow waxy solid	Not determined
				Hydrogenated bisphenol A	(CH3)2C(C6H10OH)2	Yellow wet solid	Not determined
Cis-1, 2-cyclohexanediols	C6H10(OH)2	Yellow liquid
				Esterdiol 204	HOCH2C(CH3)2CO2CH2C(CH3)2CH2OH	Yellow liquid
Neopentyl glycol	HOCH2C(CH3)2CH2OH	Light yellow liquid
				Dipropylene glycol	HOC3H6OC3H6OH	Light yellow liquid
Ethylene glycol	HOCH2CH2OH	Yellow liquid
				1, 4-butanediol	HO(CH2)4OH	White waxSolid in the form of	55.4
Pentaerythritol	C(CH2OH)4	White waxy solid	86.1
				Polypropylene glycol 1000	H(OCH(CH3)CH2)nOH	Dark yellow liquid
Trans-1, 2-cyclohexanediols	C6H10(OH)2	Yellow liquid
				2, 3-butanediol (meso form)	CH3CH(OH)CH(OH)CH3	White waxy solid	89.8
2, 2, 4-Trimethyl-1, 3-pentanediol	(CH3)2CHCH(OH)C(CH)3CH2OH	Yellow liquid

Example 2

Preparation of bis [3- (triethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate

A2 liter three neck flask equipped with a magnetic stirrer, thermometer, reflux condenser, addition funnel was charged with 199.4 grams of molten cyclohexanedimethanol (available from Aldrich), 685.6 grams of SILQUEST under a nitrogen blanket^*A-1310 (3-isocyanatopropyltriethoxysilane, available from Witco Corp.) and 0.44 grams of DBTDL. With good mixing and little heating, the flask contents exothermically reached 146 ℃. The temperature of the reaction mixture was maintained at 90-110 ℃ for 3 hours. The infrared spectrum of the reaction mixture was measured at intervals as the reaction proceeded. When the isocyanate is at 2272cm^-1When the absorption peak at (B) was substantially disappeared, the reaction was considered to be completed. Once cooled, a white solid was obtained. The melting point of the material, as measured by DSC (differential scanning calorimetry), was 82.6 ℃. Of the product¹³C and²⁹si NMR analysis confirmed bis [3- (triethoxysilyl) propyl ] group]Formation of (E) -1, 4-cyclohexanedimethyldicarbamate.

Example 3

Preparation of bis [3- (trimethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate

SILQUEST to be purchased^*Y-5187 (3-isocyanatopropyltrimethoxysilane, available from WitcoCorp.) was distilled and analyzed by GC to give a purity of 98.5%. To a 100 ml three-necked flask equipped with a magnetic stirrer, thermometer, reflux condenser, addition funnel was added 21.9 g of molten cyclohexanedimethanol and 0.0101 g (10 ml) of DBTDL under nitrogen. The contents were heated to 50 ℃. Distilled Y-5187 (3-isocyanatopropyltrimethoxysilane) was added dropwise with good stirring. Upon initial addition, an exotherm occurred and the temperature of the reaction mixture rose to 100 ℃. The heat source was removed and Y-5187 was continued at a rate such that the internal temperature was below 100 ℃. After the addition was complete, the reaction mixture was 85 deg.f. And keeping for 1 hour. Infrared analysis showed no isocyanate. After cooling to room temperature, the product was a waxy solid.

Example 4

Preparation of bis [3- (trimethoxysilyl) propyl ] -1, 4-cyclohexanedimethyldicarbamate in liquid form

A2 liter three neck flask equipped with a magnetic stirrer, thermometer, reflux condenser, addition funnel was charged with 350.6 grams of molten cyclohexanedimethanol (available from Aldrich) and 1.3 grams of DBTDL under a nitrogen blanket. With good mixing, SILQUEST was added dropwise^*Y-5187 silane (95.3% purity, 953.7 g) was added at a rate such that the internal temperature was maintained at 70-90 ℃. The addition time was 3.5 hours, and after the end of the addition, the reaction mixture was held at 85 ℃ for 1 hour and the mixture was stirred at room temperature for 17 hours. The completion of the reaction was confirmed by infrared spectroscopy. The reaction product was a viscous liquid with a Gardner Holt viscosity of X +1/2(15.3 stokes).

Example 5

Preparation of bis [3- (triethoxysilyl) propyl ] -1, 2-cyclohexanedimethyldicarbamate

To a 100 ml three-necked flask equipped with a magnetic stirrer, thermometer, reflux condenser, addition funnel was added 2.13 g of cis-1, 2-cyclohexanedimethanol (ex Acros), 7.50 g of SILQUEST under a nitrogen blanket^*A-1310 (3-isocyanatopropyltriethoxysilane, from Witco Corp.) and 0.0119 g DBTDL (dibutyltin dilaurate). The reaction mixture was heated at 100 ℃ for 2 hours. The completion of the reaction was controlled and confirmed by infrared spectroscopy. The reaction product is a viscous liquid.

Example 6

Two samples of carboxyl functional polyester resin were obtained, DSM products P-5500 and P-3900. The effect of the solid silane on the glass transition temperature (Tg) of the polyester resin was examined by DSC. The solid silane was the adduct of isocyanatopropyltriethoxysilane and 1, 4-cyclohexanedimethanol from example 2.

In both tests, the Tg of P-5500 was determined to be 57.5 ℃ and 58.2 ℃ respectively. After addition of 5% by weight of silane, the Tg of the mixture was determined to be 59.4 ℃.

The Tg of P-3900 was determined to be 59.2 ℃. After 5% by weight of silane had been added, the Tg of the mixture was determined to be 58.7 ℃.

These results indicate that the addition of the silane component of the present invention does not substantially adversely affect the Tg of the resins typically used in applying the powder.

Example 7

Powder coating formulations 7A and 7B were prepared from the ingredients listed in table II, where the values are in parts by weight. The ingredients were dry mixed using a Prism Pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 extruder at about 100 ℃. The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 200 mesh sieve.

TABLE II

Composition (I)	Comparative example 7A	7B examples of the invention
			Glycidyl methacrylate resin (PD 3402, Anderson Development)	72.18	67.85
Dodecanedioic acid	22.34	21.0
			Example 2 silane	0	6.00
Flow modifier (Modaflow III, Solutia)	2.18	2.05
			Tinuvin 900(Ciba-Geigy)	1.42	1.34
Tinuvin 144(Ciba-Geigy)	0.94	0.88
			Benzoin	0.94	0.88

The third formulation 7C was prepared as follows: to the part 7B formulation was added a sufficient amount of a solvent solution of dibutyltin dilaurate catalyst to obtain a catalyst content of 0.053 wt% and the solvent was evaporated.

Three powder coating formulations were electrostatically sprayed (using a Nordson Versa-Spray II gun) onto 3 inch x 6 inch x 0.032 inch (76 mm x 152 mm x 0.8 mm) steel Q plates. The coated panels were baked at 180 ℃ for 18 minutes and the physical properties of the coated panels were tested and the results are shown in Table III:

TABLE III

Sample (I)	Hardness of pencil1	Swinging (Koenig)2Second of	Initial gloss		20 degree gloss retention4％	MEK double-sided rubbing5
										60 degree gloss3	20 degree gloss3
7A	5H	176	95.1	65.3	70.6	100
							7B	5H	169	94.8	65.0	77.5	600
7C	5H	162	93.6	62.4	84.3	800

¹American Society for Testing and Materials (ASTM) D-3363-74

²American Society for Testing and Materials (ASTM) D-4366-84

³American Society for Testing and Materials (ASTM) D-523

⁴The cured coating was subjected to abrasion by an American Association of textile dyers (AATCC) crockfastmeter. The panels were coated with a thin dry layer of BON AMI * brand polish. The teeth of the crockmeter were covered with felt cloth, and the teeth of the crockmeter were subjected to ten double rubs. Record 20 ° gloss Retention of damaged area versus undamaged area⁴The percentage ratio was found to be%.

⁵American Society for Testing and Materials (ASTM) D-4752-87

The results show that the scratch and solvent resistance of the formulations containing the silanes of the invention are improved without a reduction in the other properties tested.

When coated plaques were prepared as above but cured only for 15 minutes at 180 deg.C, then a 1: 1 (by weight) mixture of the 7A, 7B formulation and 7A, 7B gave pencil hardness results of 5H. Formulation 7A, however, without any silane compound of the present invention, gave a pencil hardness of 3H.

Example 8

Powder coating formulations 8A and 8B were prepared from the ingredients listed in table IV, with the values being in parts by weight. Using commercially available SILQUEST^*Y-11570(1, 3, 6-tris [ propyltrimethoxysilyl)]Isocyanurate, available from Witco Corp.). The ingredients were dry mixed using a Ptism Pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 extruder at about 100 ℃. The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh screen and sprayed onto the steel substrate as described above.

TABLE IV

Composition (I)	8A comparative example	8B examples of the invention
			Glycidyl methacrylate resin (PD 3402, Anderson Development)	72.18	70.00
Dodecanedioic acid	22.34	21.67
			Isocyanuric acid silane ester (Y-11570)	0	3.00
Flow modifier (Modaflow III, Solutia)	2.18	2.12
			Tinnafen 900(Ciba-Geigy)	1.42	1.38
Tinnafen 144(Ciba-Geigy)	0.94	0.87
			Benzoin	0.94	0.87

Physical property tests were performed on the coated panels and the results are shown in table V:

TABLE V

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		20 degree gloss retention%	MEK double-sided rubbing
										60 degree gloss	20 degree gloss
8A	5H	192	99.2	79.7	70.6	100
							8B	5H	200	99.5	80.6	91.2	280

Example 9

Powder coating formulations 9A and 9B were prepared from the ingredients listed in table VI, with the values being in parts by weight. The ingredients were dry mixed on a roller mill. The mixture was then melt mixed in a Braebender mixer at about 110 ℃. The cooled extrudates were ground to a powder in a Retsch/Erinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

TABLE VI

Composition (I)	Comparative example 9A	9B examples of the invention
			Polyester resin (Crylcoat 450, UCB)	121.2	119.6
Titanium dioxide (R-960, DuPont)	66.6	65.8
			TGIC(Araldite PT810P，Ciba)	9.2	9.1
Example 2 silane	0	2.5
			Flow modifier (Modaflow III, Solutia)	2.2	2.2
Benzoin	0.8	0.8
			Dibutyl tin dilaurate	0	0.05

The powder coating formulations were electrostatically sprayed (using a Nordson Versa-spray II gun) onto 3 inch x 5 inch x 0.032 inch (76 mm x 152 mm x 0.8 mm) steel Q plates. The coated panels were baked at 180 ℃ for 15 minutes.

The scratch performance of these coatings was evaluated using the american association of textile dyers (AATCC) crockfastometer test method described above. The results show that the silane of example 2 retained 66.7% of its gloss, in contrast to 50.5% of the comparative formulation. This indicates an improvement in the scratch resistance imparted by the silanes of the present invention.

Example 10

Silane urea compounds used as powder coating additives were obtained from the reaction of isocyanate and amine compounds in table VII. The reaction is carried out under such conditions: the total weight was about 30 grams, the equivalent ratio of isocyanate to amine was 1: 1.03, and no catalyst was used in the reaction. Otherwise, the reaction conditions were as described in example 1.

TABLE VII

Isocyanates	Amines as pesticides	Shape of the product	Melting Point (. degree.C.)
				Isocyanatopropyl trimethoxysilane	1, 6-hexanediamine	White solid in lump form	136
Isocyanatopropyl trimethoxysilane	Ethylene diamine	White waxy solid	121
				Isocyanatopropyl trimethoxysilane	1, 2-diaminocyclohexane	Brown paste	114
Isocyanatopropyl trimethoxysilane	Trans-1, 2-diaminocyclohexane	White hard solid	198
				Isocyanatopropyl trimethoxysilane	1, 3-diaminopropane	White block solid	116
Isocyanatopropyl trimethoxysilane	1, 3-ringsHexane-bis-methylamine	Yellow hard solids	79
				Isocyanatopropyl trimethoxysilane	1, 4-diaminobutane	Yellow-brown quick-drying agent
Bis- (isocyanatobenzene) Methane (MDI)	3-aminopropyltriethoxysilane	White hard solid	67
				Bis- (4-isocyanatocyclohexyl) methane (Desmodur W)	3-aminopropyltriethoxysilane	White hard solid	127
1, 6-diisocyanatohexane	3-aminopropyltriethoxysilane	Yellow block solid	117
				Isophorone diisocyanate	3-aminopropyltriethoxysilane	Yellow block solid	105
1，3-bis (isocyanatomethyl) cyclohexane	3-aminopropyltriethoxysilane	Yellow block solid	70
				Bis- (4-isocyanatocyclohexyl) methane (Desmodur W)	3-aminopropylmethyldiethoxysilane	White block solid	77

Example 11

To a solution of 4.7 g tetrahydrofuran, 0.3 g water, pH adjusted to 3.0 with acetic acid, 1.0 g alkyltriethoxysilane (Silquest) was added^*A-137, available from Witco Corp.). Stirred in a Warring mixer for 20 minutes under high shear, then added to 100 grams of titanium dioxide (Tiona RC1-9 available from millenium Inorganic Chemicals). After drying in an oven at 150 ℃, the treated titanium dioxide was formulated into a polyester/TGIG powder coating formulation (11B).

To a solution of 1.0 g methanol, 0.85 g water, 0.2 g acetic acid, 11.2 g trimethoxy alkylene oxide silane (Silquest) was added^*A-187, available from Witco Corp.). Stirred in a Warring mixer under high shear for 30 minutes, then added to 100 grams of titanium dioxide. After drying in an oven at 160 ℃, the treated titanium dioxide was formulated into a polyester powder coating formulation (11C).

Powder coating formulations 11A, 11B and 11C, prepared from the ingredients listed in Table VIII, where the values are in parts by weight. The ingredients were dry mixed using a prism pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 twin-screw extruder at about 100 ℃. The formulations were extruded sequentially, i.e. first 11A, then 11B, then 11C.

The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

TABLE VIII

Composition (I)	11A	11B	11C
				Crylcoat * 450, UCB, polyester resin	218.0	218.0	200.0
R-960, DuPont, titanium dioxide	160.0	-	-
				Silane treated TiO2，Silquest*A-137Silquest*A-187	--	160.0-	-92.6
Araldite*PT810P，Ciba，TGIC	16.4	16.4	10.25
				Modaflow*III, Solutia flow regulators	4.0	4.0	3.0
Benzoin	1.6	1.6	1.0

The powder coating formulations were electrostatically sprayed (using a Nordson Versa-spray II gun) onto 3 '. times.6 '. times.0.032 ' (76 mm. times.152 mm. times.0.8 mm) steel Q plates. The coated panels were baked at 180 ℃ for 18 minutes.

Two formulations: comparative formulation 11A (conventional TGIC/polyester powder coating formulation) and the invention (formulation 11C, where a portion of the TGIC was dispensed with) gave physical properties on coated panels as shown in table IX.

TABLE IX

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		MEK double-sided rubbing
						60 degree gloss	20 degree gloss
			11A	5H				188	91.6	75.2	222
11C	5H	186			88.0	66.0	2000

The results show that replacing some of the TGIC with the silane treated filler or pigment of the present invention improves the solvent resistance of the coating.

Example 12

To a solution of 2.0 g methanol, 1.5 g water, 0.4 g acetic acid, 20.0 g Silquest was added^*A-187 trimethoxy alkylene oxide silane. Stirred in a Warring mixer under high shear for 30 minutes, then added to 100 grams of titanium dioxide. Drying in an oven at 165 deg.C, and processingThe treated titanium dioxide was formulated into a polyester powder coating formulation (12A).

Powder coating formulation 12A was prepared from the ingredients listed in table X, where the values are in parts by weight. Titanium dioxide was treated in the manner described above and the ingredients were dry mixed using a Prism Pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 twin-screw extruder at about 100 ℃. As in example 11, the formulation described as 11A was extruded, followed by the formulation described as 11B, and finally the 12A formulation.

The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

Table X

Composition (I)	12A invention
		Crylcoat * 450, UCB, (polyester resin)	200.0
Silane treated titanium dioxide	155.6
		Araldite*PT810P，Ciba-Geigy TGIC	1.5
Modaflow*III, Solutia flow regulators	4.4
		Benzoin	1.5

The powder coating formulations were electrostatically sprayed (using a Nordson Versa-spray II gun) onto 3 '. times.6 '. times.0.032 ' (76 mm. times.152 mm. times.0.8 mm) steel Q plates. The coated panels were baked at 180 ℃ for 18 minutes.

The following physical property test results were obtained on the coated panels.

TABLE XI

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		MEK double-sided rubbing
						60 degree gloss	20 degree gloss
			11A	5H				188	91.9	75.2	222
12A	5H	200			83.3	46.3	600

The results show that formulations containing the silane-treated fillers or pigments of the present invention have improved solvent resistance.

Example 13

To a solution of 2.0 g methanol, 1.5 g water, 0.4 g acetic acid, 20.0 g Silquest was added^*187 trimethoxy alkylene oxide silane. Stirred in a Warring mixer under high shear for 30 minutes, then added to 100 grams of titanium dioxide. After drying in an oven at 165 ℃, the treated titanium dioxide was formulated into a polyester powder coating formulation (13A).

Powder coating formulation 13A was prepared from the ingredients listed in table XII, where the values are in parts by weight. Titanium dioxide was treated in the manner described above and the ingredients were dry mixed using a Prism Pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 twin-screw extruder at about 100 ℃. As in example 11, the formulation described as 11A was extruded, followed by the formulation described as 11B, and finally the 13A formulation.

The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

TABLE XII

Composition (I)	13A invention
		Crylcoat * 450, UCB, (polyester resin)	272.5
Silane treatment (titanium dioxide)	200.0
		Modaflow*III, Solutia flow regulators	5.0
Benzoin	2.0

The powder coating formulations were electrostatically sprayed (using a Nordson Versa-spray II gun) onto 3 '. times.6 '. times.0.032 ' (76 mm. times.152 mm. times.0.8 mm) steel Q plates. The coated panels were baked at 180 ℃ for 18 minutes.

The following physical property test results were obtained on the coated panels.

TABLE XIII

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		MEK double-sided rubbing
						60 degree gloss	20 degree gloss
			11A	5H				188	91.9	75.2	222
13A	5H	200			84.6	47.3	390

The results show that fillers or pigments treated with silanes, according to the invention, can replace TGIC.

Example 14

12.5 g of amino-bis- (propyltrimethoxysilane) (Silquest)^*A-1170 from WitcoCorp.) and 2.0 g methanol were added to 100 g of titanium dioxide. After mixing in a Warring mixer, the treated titanium dioxide was air dried overnight.

Powder coating formulation 14A (standard TGIC/polyester formulation) and 14B formulation of the invention, prepared from the ingredients listed in table XIV, where the values are in parts by weight. The treated titanium dioxide was prepared in the manner described above, with the ingredients dry mixed using a Prism Pilot3 high speed mixer. The mixture was then extruded sequentially on a Braebender PL-2000 single screw extruder at about 105 ℃. The 14A formulation was extruded first, followed by the 14B formulation.

The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

TABLE XIV

Composition (I)	14A comparative example	14B examples of the invention
			Crylcoat * 450, UCB, (polyester resin)	218.0	200.0
Dupont R-960 titanium dioxide	160.0	-
			Silane treated titanium dioxide	-	147.0
Araldite*PT810P，Ciba-Geigy TGIC	16.4	-
			Modaflow*III, Solutia flow regulators	4.0	4.4
Benzoin	1.6	1.5

The coated steel Q plate was sprayed and baked in the same manner as in the above example. The following physical property test results were obtained on the coated panels.

TABLE XV

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		MEK double-sided rubbing	Network bonding1
							60 degree gloss	20 degree gloss
			14A	5H					178	91.2	79.4	135	4-5
14B	5H	214			82.6	46.6	130	4-5

¹ASTM D-3359

The results show that complete replacement of TGIC with the silane treated filler of the present invention is feasible.

Example 15

To a solution of 4.7 g tetrahydrofuran, 0.3 g water, pH adjusted to 3.0 with acetic acid, 1.0 g triethoxyalkylsilane (Silquest) was added^*A-137, available from Witco Corp.). Stirred in a Warring mixer for 20 minutes under high shear and then added to 100 grams of titanium dioxide. After drying in an oven at 150 ℃, the treated titanium dioxide was formulated into polyester/TGIC powder coating formulations (15B and 15C).

Powder coating formulations 15A, 15B, and 15C, prepared from the ingredients listed in Table XVI, where the values are in parts by weight. The ingredients were dry mixed using a Prism Pilot3 high speed mixer. The mixture was then extruded on a Werner and Pfleiderer ZSK-30 twin-screw extruder at about 100 ℃. The 15A formulation was extruded first, followed by 15B, and then 15C.

The cooled extrudate was ground to a powder in a Retsch/Brinkman ZM-100 mill. The powder was sieved through a 140 mesh sieve.

The physical properties of each formulation were evaluated. Reference formulation 15A is a standard TGIC/polyester formulation. Formulations 15B and 15C are comparative examples showing the effect of silane treatment with alkyltrialkoxysilanes.

TABLE VIII

Composition (I)	Reference example 15A	15B comparative example	15C comparative example
				Crylcoat * 450, UCB, polyester resin	327.0	327.0	327.0
R-960, DuPont, titanium dioxide	240.0	-	-
				Silane treated TiO2-Silquest* A-137	-	246.0	252.0
Araldite*PT810P，Ciba，TGIC	24.6	18.6	12.6
				Modaflow*III, Solutia flow regulators	6.0	6.0	6.0
Benzoin	2.4	2.4	2.4

The coated steel Q panels were sprayed and baked in the same manner as in the previous examples. The following physical property test results were obtained on the coated panels.

TABLE XVII

Sample (I)	Hardness of pencil	Second swing (Koenig)	Initial gloss		MEK double-sided rubbing
						60 degree gloss	20 degree gloss
			15A	5H				188	90.4	64.5	204
15B	5H	188			88.1	39.5	12
			15C	5H				193	95.0	51.9	14

The loss of MEK rub resistance relative to the reference indicates that the silane treated filler of the comparative example cannot replace some of the TGIC amounts of the reference formulation.

The foregoing embodiments and disclosures are illustrative and not exhaustive. These embodiments and descriptions will suggest many variations and alternatives to one of ordinary skill in the art. All such substitutions and modifications are intended to be included within the scope of the appended claims. For example, while the preparation of the silane of the present invention containing a powder coating formulation is illustrated as a primary example for a silane prepared by the reaction of an active hydrogen compound with an isocyanate, it will be understood that: other silane compounds within the scope defined by structural formula I above can be readily prepared and used in the formulations of the present invention. Likewise, other silane-treated fillers within the scope of the appended claims may be prepared in a manner similar to the above-described procedure. Those skilled in the art will recognize that: equivalents to the specific embodiments described herein are also intended to be encompassed by the appended claims.

Claims (22)

1. A powder coating or adhesive formulation comprising:

(A) at least one silane of formula a, or a hydrolysate or condensate of the silane:

in the formula R¹Is C₁-C₆Alkyl radical, R³Is C₂-C₆Alkylene, one of A and B being NH and the other being an oxygen atom, X being C₄-C₁₂Straight chain,Branched or cyclic alkyl, m is 1-4; and

(B) at least one organic resin component selected from polyesters.

2. A powder coating or adhesive formulation as claimed in claim 1, wherein the polyester is a glycidyl methacrylate resin.

3. The powder coating or binder formulation as claimed in claim 1, wherein the silane carbamate is solid at room temperature and has a melting point of 30-170 ℃.

4. The powder coating or adhesive formulation of any one of claims 1-3, wherein R¹Is methyl or ethyl, X is C_4-12Saturated straight, branched or cyclic alkyl.

5. The powder coating or adhesive formulation of any one of claims 1-3, wherein the silane is isocyanato C_2-6Alkyl tri (C)_1-6Alkoxy) silanes with a compound selected from: an addition product of one of 2, 3-butanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, 1, 4-cyclohexanediol, 1, 7-heptanediol, 1, 8-octanediol, pentaerythritol, 1, 12-dodecanediol, 1, 10-decanediol, 3, 6-dimethyl-4-octyne-3, 6-diol, 1, 9-nonanediol, and 1, 4-butanediol.

6. The powder coating or adhesive formulation of any one of claims 1-3, wherein X is C_4-12A symmetrical alkyl group.

7. The powder coating or adhesive formulation of any one of claims 1-3, wherein m is 2.

8. The powder coating or adhesive of any one of claims 1-3A cocktail formulation wherein X is methylenecyclohexylidenemethylene, R¹Is ethyl.

9. The powder coating or adhesive formulation according to any one of claims 1 to 3, wherein the formulation contains polydimethylsiloxane.

10. The powder coating or adhesive formulation of any one of claims 1-3, wherein the formulation comprises a compound selected from the group consisting of: thermoplastic polymers of nylon, polyolefin, polyphenylene sulfide or polyvinyl chloride.

11. Powder coating or adhesive formulations containing a filler or pigment which is modified with a silane of formula a:

and at least one compound of a hydrolysate or condensate of said silane, wherein R is¹Is C₁-C₆Alkyl radical, R³Is C₂-C₆Alkylene, X is C₄-C₁₂Straight, branched or cyclic alkyl, one of A and B is NH and the other is O, m is 1-4, and the pigment or filler is titanium dioxide.

12. The powder coating or adhesive formulation of claim 11, wherein the R¹Is methyl or ethyl, X is C_4-12Saturated straight, branched or cyclic alkyl.

13. The powder coating or adhesive formulation of any one of claims 11-12, wherein the silane is isocyanato C_2-6Alkyl tri (C)_1-6Alkoxy) silanes with a compound selected from: 2, 3-butanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, 1, 4-cyclohexanediol, 1, 7-heptanediol, 1, 8-octanediol, pentaerythritol, 1, 12-dodecanediolAn addition product of one of alkanediol, 1, 10-decanediol, 3, 6-dimethyl-4-octyne-3, 6-diol, 1, 9-nonanediol and 1, 4-butanediol.

14. The powder coating or adhesive formulation of any one of claims 11-12, wherein the X is C_4-12A symmetrical alkyl group.

15. The powder coating or adhesive formulation of any one of claims 11-12, wherein the m is 2.

16. The powder coating or adhesive formulation of any one of claims 11-12, wherein X is methylenecyclohexylidenemethylene, R¹Is ethyl.

17. The powder coating or adhesive formulation according to any one of claims 11-12, wherein the formulation contains polydimethylsiloxane.

18. The powder coating or adhesive formulation according to any one of claims 11 to 12, wherein the formulation comprises a compound selected from the group consisting of: thermoplastic polymers of nylon, polyolefin, polyphenylene sulfide or polyvinyl chloride.

19. A filler or pigment treated with a silane of formula a, or a hydrolysate or condensate of said silane:

wherein R is as defined in¹Is C_1-6Alkyl radical, R³Is C_2-6Alkylene, X is C_4-12Straight, branched or cyclic alkyl, one of A and B is NH and the other is O, m is 1-4, and the filler or pigment is titanium dioxide.

20. The filler or pigment of claim 19, wherein the silane is isocyanato C_2-6Alkyl tri (C)_1-6Alkoxy) silanes with a compound selected from: an addition product of one of 2, 3-butanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, 1, 4-cyclohexanediol, 1, 7-heptanediol, 1, 8-octanediol, pentaerythritol, 1, 12-dodecanediol, 1, 10-decanediol, 3, 6-dimethyl-4-octyne-3, 6-diol, 1, 9-nonanediol, and 1, 4-butanediol.

21. The filler or pigment of claim 19 or 20, wherein m is 2.

22. The filler or pigment of claim 19 or 20, wherein X is methylenecyclohexylidenemethylene, R¹Is ethyl.