MXPA99006925A - Epoxy-polysiloxane polymer composition - Google Patents

Abstract

Epoxy-polysiloxane polymer compositions of this invention are prepared by combining a resin component with a hardener component. The resin component comprises a non-aromatic epoxy rein ingredient and a polysiloxyne ingredient. The hardener component comprises an amine and optionally an organotin catalyst. The composition can also include aggregates, pigments, and other additives depending on the particular end use. The composition is prepared using a sufficient amount of water to promote hydrolysis of the polysiloxane and the polycondensation of the silanols produced by such hydrolysis. In its cured form, the epoxy-polysiloxane composition exists as a uniformly dispersed arrangement of linear epoxy chain fragments that are cross-linked with a continuous polysiloxane polymer chain, thereby forming a non-interpenetrating polymer network chemical structure that has substantial advantages over conventional epoxy systems. Protective coatings formed from such compositions exhibit excellent weatherability in sunlight, and superior chemical and corrosion resistance after curing.

Description

POLYMERIC COMPOSITION OF EPOXY-POLYSYLLOXAN Field of the Invention This invention relates to compositions based on epoxy resin, useful for protective coatings and the like and, more specifically, to an epoxy-polyxane polymer composition having improved properties of flexibility, resistance to environmental conditions, resistance to compression and resistance. chemistry.

Background of the Invention Epoxy coating materials are well known and have gained commercial acceptance as protective and decorative coatings for steel, aluminum, for galvanization, wood and concrete in maintenance, in the navy, construction, in the architectural area, in aircraft and markets finished products. The basic raw materials used to prepare these coatings generally comprise as essential components (a) REF .: 30915 an epoxy resin, (b) a hardener and (c) a pigment or aggregate component. Known epoxy-based coating materials often contain several components in addition to the epoxy, hardener and pigment / aggregate, such as non-reactive diluents and reactants including mono- and di-epoxides, plasticizers, bituminous and asphaltic extenders, adhesion promoters, suspending and thixotropic agents, surfactants, corrosion inhibitors, ultraviolet light sterilizer, catalysts and rheology modifiers. The resin components and the hardener may also contain volatile organic solvents which are used to lower the viscosity of the composition, thereby providing a suitable consistency for spray application with conventional air, airless and electrostatic spray equipment. Epoxy-based protective coatings have many properties that can make them desirable as coating materials. These are readily available and are ea applied by a variety of methods including spraying, roller application and brushing. These adhere perfectly to steel, concrete, and other substrates, have low moisture vapor transmission rates and act as water barriers, upon entry of the chloride and sulfate ions, provide excellent protection against corrosion under a variety of conditions. of atmospheric exposure and have good resistance to many chemicals and solvents. Epoxy-based coating materials generally do not have good resistance to environmental conditions in sunlight. While such coatings maintain their resistance to chemicals and corrosion, exposure to the ultraviolet light component of sunlight results in a surface degradation phenomenon known as an abatement which changes the luster and color of the original coating. Where color and luster retention is desired or required, epoxy-based protective coatings are typically topcoated with a coating that is more resistant to environmental conditions, for example, an alkyd, vinyl or aliphatic polyurethane coating. . The end result is a two or sometimes three component coating system which provides resistance to corrosion and resistance to environmental conditions, but which is also labor intensive and expensive to apply. While epoxy-based coating materials have gained wide commercial acceptance, there nevertheless remains a need for epoxy-based materials with improved color and luster retention, better resistance to chemicals and corrosion, and improved resistance to mechanical abuse. . The new epoxy coating materials are necessary to comply with the new environmental regulations and for governmental health hazards. Epoxy coating materials with improved color and luster retention are needed wherever they can be exposed to sunlight. An epoxy coating that does not work and does not require an upper coating resistant to environmental conditions, It is desirable. The coating materials with improved resistance to chemicals, corrosion, impact and abrasion, are necessary for containment structures of primary and secondary chemicals, to protect steel and concrete in the treatment with chemical products, power generation, railroad cars, wastewater treatment water, and the paper and pulp processing industries. To date, epoxy coatings with improved resistance to environmental conditions have been obtained by modification with acrylic resin or by curing with epoxy resins inherently resistant to environmental conditions, for example, sorbitol-glycidyl ethers, hydrogenated reaction products of bisphenol A and epichlorohydrin, and more recently the resins of melamine co-esterified with epoxy functional group, of Monsanto with polyamide, acrylic or polyester resins with cycloaliphatic or carboxyl amine functional group. Another method has been the use of epoxidized polyester resins in combination with certain vehicles with a carboxyl functional group. While these coatings show improved resistance to environmental conditions, their resistance to chemicals and corrosion is generally inferior to the previously described epoxy-based coatings.

Therefore, an object of the present invention is to provide an epoxy-based coating composition having improved resistance against chemicals, against corrosion and against environmental conditions.

Brief Description of the Invention An epoxy siloxane composition is prepared, according to the principles of this invention, by the combination of the following ingredients: (a) a resin component based on a mixture of a non-aromatic epoxy resin having at least two groups 1 , 2-epoxide with a polysiloxane; (b) a difunctional amine hardening component which may be substituted wholly or in part with an aminosilane; (c) an optional catalyst; (d) a pigment or aggregate component; and (e) water. The epoxy-polysiloxane composition is prepared by using, in the range of about 10 to 60% by weight, of an epoxy, non-aromatic resin ingredient, 15 to 60 weight percent of polysiloxane, 5 to 40 percent by weight. weight of amine hardener, and up to about five percent by weight of catalyst. The above-identified ingredients react to form a non-interpenetrating network composition comprising a continuous phase epoxy siloxane copolymer. The epoxy siloxane compositions of this invention show improved resistance to ultraviolet light and environmental conditions in sunlight, as well as improved resistance against chemicals and corrosion, when compared to conventional epoxy resin based coatings. In addition, the epoxy-polysiloxane compositions of this invention show color retention and luster approaching a level shown by the aliphatic polyurethanes and may, depending on the application, avoid the need for topcoating.

Detailed description The epoxy polysiloxane composition is prepared, according to the principles of this invention, by the combination in the presence of water of: (a) a resin component comprising a non-aromatic epoxide resin and polysiloxane; (b) a hardening component; (c) an optional organotin catalyst; and (d) an optional pigment and / or aggregate component. The epoxy-polysiloxane compositions of this invention may also contain other components such as rheology modifiers, plasticizers, thixotropic agents, antifoaming agents and solvents and the like, to achieve the desired properties sought by the user. The resin component comprises a mixture of epoxide resin and polysiloxane. Epoxy resins useful in the formation of the epoxy-polysiloxane composition are hydrogenated, non-aromatic epoxy resins containing more than one 1,2-epoxide group per molecule. A preferred epoxy, aromatic resin comprises two 1,2-epoxide groups per molecule. The epoxy resin is preferably in liquid form instead of solid, has an epoxide equivalent weight in the range of about 100 to 5,000, and has a reactivity of about two. Preferred epoxy resins include hydrogenated, non-aromatic cyclohexanedimethanol and diglycidyl ethers of hydrogenated Bisphenol A epoxide resins, such as Epon DPL-862, Eponex 1510, Heloxy 107 and Eponex 1513 (epoxy resin of bisphenol A-hydrogenated epichlorohydrin) Shell Chemical in Houston, Texas; Santolink LSE-120 from Monsanto located in Springfield, Massachusetts, Epodil 757 (cyclohexane-dimethanol-diglycidyl ether) from Pacific Anchor located in Allentown, Pennsylvania; Araldite XUGY358 and PY327 of Ciba Geigy located in Hawthorne, New York; Epirez 505 of Rhone-Poulenc located in Louisville, Kentucky; Aroflint 393 and 607 from Reichold Chemicals located in Pensacola, Florida; and ERL4221 of Union Carbide located in Tarrytown, New York. Other suitable non-aromatic epoxy resins include DER 372 and DER 736; Heloxy 67, 68, 107, 48, 84, 505 and 71 each from Shell Chemical; PolyBD-605 from Arco Chemical of Newtown Square, Pennsylvania; Erisys GE-60 from CVC Specialty Chemicals, Cherry Hill, New Jersey; and Fineclad A241 from Reichold Chemical.

Such hydrogenated, non-aromatic epoxy resins are desired for their limited reactivity of about two, which promote the formation of a linear epoxy polymer and prohibit the formation of a crosslinked epoxy polymer. It is believed that the resulting linear epoxy polymer formed by the addition of the hardener to the epoxy resin is responsible for the improved strength against the environmental conditions of this composition. The use of such epoxy resins nonaromatic to form a durable protective coating to ambient conditions, has never been previously explored because of the limited reactivity of the epoxide resin and therefore, the perceived inability of the resin to cure to form a protective coating. A preferred epoxy-polysiloxane composition comprises epoxy resin in the range of 10 to 60 weight percent. If the composition comprises less than 10 weight percent epoxide resin, the chemical resistance of the coating will be compromised. If the composition comprises more than about 60 weight percent epoxy resin, the resistance to the environmental coating conditions will be compromised. A particularly preferred composition comprises about 25 weight percent of non-aromatic epoxy resin. With respect to the polysiloxane used to constitute the resin component, preferred polysiloxanes include, but are not limited to, those having the following formula: wherein each Ri is selected from the group consisting of the hydroxyl group and the alkyl, aryl and alkoxy groups having up to six carbon atoms. Each R 2 is selected from the group consisting of hydrogen and alkyl and aryl groups having up to six carbon atoms. It is preferred that Ri and R2 comprise groups having less than six carbon atoms, to facilitate the rapid hydrolysis of the polysiloxane, whose reaction is promoted by the volatility of the analogous alcohol product of the hydrolysis. Groups Ri and R2 having more than six carbon atoms tend to impair the hydrolysis of the polysiloxane due to the relatively low volatility of each alcohol analogue. It is preferred that the subscript * n "is selected so that the ingredient polysiloxane having a molecular weight in the range of about 400 to 10,000. An ingredient of polysiloxane having a molecular weight of about 400 can produce a composition that could be fragile. an ingredient polysiloxane having a molecular weight greater than about 10,000 can produce a composition having a viscosity outside a desired approximately 3.000 to 15.000 centipoise (cP) at 20 ° C range, making the composition too viscous for application without adding solvent in excess of current requirements of the content of volatile organic compounds (VOC). the ingredients of preferred polysiloxanes are polysiloxanes with silanol functional alkoxy group and. polysiloxanes functional group alkoxy particularly preferred are polysiloxanes with functional group methoxy and include, but are not limited to: DC-3 074 and DC-3037 from Dow Corning; GE SR191, SY-550 and SY-231 from Wacker located in Adrian Michigan. Preferred silanol-functional polysiloxanes include, but are not limited to, intermediates DC840, Z6018, Ql-2530 and 6-2230 from Dow Corning. A preferred epoxy-polysiloxane composition comprises polysiloxane in the range of 15 to 60 weight percent. By using an amount of the polysiloxane ingredient outside this range a composition having lower resistance to environmental conditions and chemicals can be produced. A particularly preferred epoxy-polysiloxane composition comprises about 30 weight percent polysiloxane. The hardening component comprises an amine chosen from the general classes of aliphatic amines, aliphatic amine adducts, polyamidoamines, cycloaliphatic amines and adducts of cycloaliphatic amines, aromatic amines, Mannich bases and ketimines. A preferred hardening component comprises a difunctional amine, for example, an amine having two active hydrogens, which may be substituted completely or in part with an aminosilane having the general formula: Y - Si - (O - X) 3 where Y is H (HNR) a, and where * a "is equal to one, each R is a difunctional organic radical independently selected from the group consisting of the aryl, alkyl, dialkylaryl, alkoxyalkyl, and cycloalkyl radicals, and wherein R may vary within of each molecule Y. Each X may be the same or different, and is limited to the alkyl, hydroxyalkyl, alkoxyalkyl and hydroxyalkoxyalkyl groups containing less than about six carbon atoms.At least 0.7 equivalents of amine may be present in the hardener component. or 0.2 moles of aminosilane per equivalent of epoxy Preferred aminosilanes include, but are not limited to: a-methyethyl-aminopropyl-triethoxysilane, n-phenylaminopropyl-trimethoxysi tin, trimethoxysilylpropyl-diethylene triamine, 3- (3-aminophenoxy) propyltrimethoxy silane, aminoethylaminotmethylphenyltrimethoxysilane, 2-aminoeti 1-3-aminopropyl, tris-2-ethylhexoxysilane, n-aminohexyl-aminopropyltrimethoxy if tin and trisa-inopropyl-trismethoxy-ethoxysilane. The manufacturers and trade names of some aminosilanes useful in the present invention are listed in Table 1 Table 1 - Aminosilanes Manufacturer Product Designation Dow Corning Z6020, XI-6100, XI6150 Union Carbide A1100, A1101, A1102, A1108, A1110, A1120, A1126, A1130, A1387, Y9632 Wacker ED117 Hüls A0696, A0698, A0699, A0700, A0710, A0720, A0733, A0733, A0742, A0750, A0800 PCR 12328-1 Preferred aminosilanes are difunctional silanes including aminopropyltrimethoxysilane and aminopropyltriethoxysilane. A particularly preferred aminosilane is Union Carbide A1100. A difunctional aminosilane is desired because it has been found that it has the combination of an aminosilane having a reactivity of two, for example, having only two amine hydrogens, reacts with the non-aromatic epoxy, which also has a reactivity of two, to form a non-crosslinked, linear epoxy polymer that exhibits improved resistance to environmental conditions.

Such preferred amines and aminosilanes produce epoxy-polysiloxane compositions which, when applied as a substrate coating, exhibit superior resistance to environmental conditions in terms of color retention and luster. A preferred epoxy polysiloxane composition comprises in the range of 5 to 40 weight percent amine and / or aminosilane. By using an amount of the amine and / or aminosilane ingredient outside this range, a composition having lower resistance to environmental conditions and lower resistance to chemicals can be produced. A particularly preferred epoxy polysiloxane composition comprises about 15 weight percent amine and / or aminosilane. Accordingly, a preferred coating composition according to the practice of the present invention may comprise a weight ratio of polysiloxane to amine and / or aminosilane of about two to one. In the preparation of epoxy polysiloxane compositions of the present invention, the proportion of the hardener component to the resin component can vary over a wide range, however whether the hardener is chosen from the general classes of amines, or from an aminosilane of the previous general formula, or any combination thereof. In general, the epoxy resin component is cured with sufficient hardener to provide at least about 0.7 to about 1.2 equivalents by weight of amine per 1 equivalent by weight of epoxide, or with at least 0.2 moles of aminosilane per equivalent weight of epoxide. If the amount of the aggregate hardener provides less than 0.7 weight percent amine equivalent per equivalent weight of epoxide, the coating and parquet composition produced will show a slow cure time and will have lower resistance to environmental conditions and lower strength. the chemical products. If the amount of hardener added provides more than 1.2 equivalent weight per equivalent weight of epoxide, the coating and parquet composition produced will show flush or surface oiliness. The epoxy-polysiloxane compositions of this invention are formulated for application with conventional equipment for air spray, airless, airless, air and electrostatic assisted, brush or roller. The compositions are intended to be used as protective coatings for steel, galvanization, aluminum, concrete and other substrates at dry film thicknesses in the range of 25 microns to about two millimeters. Accordingly, the pigment or aggregate ingredients useful in forming the composition are selected from a material of fine particle size, preferably having at least 90 percent by weight American mesh size greater than 325. Suitable pigments can be selected from organic and inorganic color pigments which can include titanium dioxide, carbon black, carbon black, zinc oxide, natural red and synthetic, oxides of yellow iron, brown and black, yellow of toluidine and benzidine, blue and green of phthalocyanine, and violet of carbazole, and extender pigments including ground and crystalline silica, barium sulfate, magnesium silicate, calcium silicate, mica, micaceous iron oxide, calcium carbonate, zinc powder, aluminum and aluminum silicate, gypsum, feldspar and the like. The amount of pigment that is used to form the composition is understood to vary, depending on the application of the particular composition, and may be zero when a clear composition is desired. A preferred epoxy-polysiloxane composition may comprise up to about 50 weight percent pigment and / or fine particle size aggregate. By using more than 50 weight percent of the pigment ingredient and / or fine particle size aggregate, a composition that is too viscous for the application can be produced. Depending on the particular end use, a preferred coating composition may comprise about 20 weight percent of the aggregate and / or pigment of fine particle size. The pigment and / or aggregate ingredient is typically added to the epoxy resin portion of the resin component and dispersed with a Cowles mixer to at least one milling fineness of Heg an 3, or alternatively is milled or ground by sand to the same fineness of grinding before the addition of the polysiloxane ingredient. The selection of a fine particle size pigment or aggregate and the dispersion or grinding to approximately one Hegman 3 milling allows the atomization of the mixed resin and the curing components with air spray equipment, without air aided air, without conventional air and electrostatic, and provides a smooth and even surface appearance after application. Water is an important ingredient of the present invention and must be present in an amount sufficient to give rise to the hydrolysis of the polysiloxane and the subsequent condensation of the silanols. The sources of water are mainly atmospheric moisture and humidity adsorbed on the pigment or aggregate material. Additional water can be added to accelerate the cure depending on environmental conditions, such as the use of the coating and parquet composition in arid environments. A preferred epoxy-polysiloxane composition comprises up to a stoichiometric amount of water to facilitate hydrolysis. Compositions that are prepared without added water may not contain the amount of moisture necessary for hydrolysis and condensation reactions, and therefore may produce a composition product that has a sufficient degree of resistance to ultraviolet light, corrosion and the chemical products. Compositions that are prepared using more than about two percent by weight of water, tend to hydrolyze and polymerize to form an undesirable gel before application. A particularly preferred epoxy-polysiloxane composition is prepared by using about one percent by weight of water. If desired, the water can be added either to the epoxy resin or to the polyamine hardener. Other sources of water may include trace amounts present in the epoxy resin, polyamine hardener, thinning solvent, or other ingredients. The water may also be incorporated by the use of ketimines or alcohol-solvent-water mixtures as described in US Patent No. 4,250,074 incorporated by reference herein. Regardless of its source, the total amount of water that is used must be the stoichiometric amount necessary to facilitate the hydrolysis reaction. Water that exceeds the stoichiometric amount is undesirable, since excess water acts to reduce the surface luster of the product in finally cured composition. Up to about five percent by weight of catalyst can be added to the resin component, or can be added as a completely separate component, to accelerate the drying and curing of the modified epoxy coating and the parquet materials of the present invention. Useful catalysts include metal driers well known in the paint industry, for example, zinc, manganese, zirconium, titanium, cobalt, iron, lead and tin, each in the form of octoates, neodecanes and naphthatates. Suitable catalysts include organotin catalysts having the general formula:Rs I I R8 where R5 and ß are each selected from the group consisting of alkyl, aryl, and alkoxy having up to eleven carbon atoms, and wherein R7 and Rs are each selected from the same groups as R5 and R6, or from the group consisting of of inorganic atoms such as halogens, sulfur or oxygen. Dibutyltin dilaurate, dibutyltin diacetate, organotitanates, sodium acetate, and secondary or tertiary aliphatic polyamines including propylamine, ethylaminoethanol, triethanolamine, triethylamine and methyldiethanolamine, alone or in combination, can be used to accelerate the hydrolytic polycondensation of the polysiloxane and silane. A preferred catalyst is dibutyltin dilaurate. The epoxy-polysiloxane compositions of the present invention are generally low in viscosity and can be applied by spraying or spraying without the addition of a solvent. However, organic solvents may be added to improve atomization and application with electrostatic spray equipment or to improve flow and leveling and appearance when applied by brush, roller, or standard air and airless spray equipment. Exemplary solvents useful for this purpose include esters, ethers, alcohols, ketones, glycols, and the like. The maximum amount of solvent added to the compositions of the present invention is limited by government regulation under the Clean Air Act, to approximately 420 grams of solvent per liter of the composition. The epoxy polysiloxane compositions of the present invention may also contain rheology modifiers, plasticizers, antifoaming agents, thixotropic agents, pigment wetting agents, bituminous and asphaltic extenders, anti-settling agents, diluents, UV light stabilizers, air release agents and dispersion aids. A preferred epoxy-polysiloxane composition may comprise up to about ten weight percent of such modifiers and agents. The epoxy-polysiloxane compositions of the present invention are supplied as a double package system in moisture proof containers. A container contains the epoxy resin, polysiloxane, any pigment and / or aggregate ingredient, additives and solvent, if desired. The second package contains polyamine and / or aminosilane and optionally catalysts or accelerating agents. The epoxy-polysiloxane compositions of the present invention can be applied and completely cured at ambient temperature conditions in the range of about -6 ° C to 50 ° C. At temperatures below -18 ° C, healing is severely retarded. However, the compositions of the present invention can be applied under baking or curing temperatures up to 150 ° C to 200 ° C.

While not wishing to be bound by any particular theory, it is believed that the epoxy-polysiloxane compositions of the present invention are cured by: (1) the reaction of the epoxy resin with the amine and / or aminosilane hardener to form epoxy polymer chains; (2) the hydrolytic polycondensation of the polysiloxane ingredient to produce alcohol and polysiloxane polymer; and (3) the copolymerization of the epoxy polymer chains with the polysiloxane polymer to form a fully cured epoxy polysiloxane polymer composition. When an aminosilane is used to form the hardening component, the amine portion of the aminosilane undergoes the epoxy-amine addition reaction, and the silane portion of the aminosilane undergoes hydrolytic polycondensation with the polysiloxane. In its cured form, the epoxy-polysiloxane composition exists as a uniformly dispersed arrangement of linear epoxy chain fragments that are cross-linked with a continuous polysiloxane polymer chain, thereby forming a non-interpenetrating polymer network chemical structure (IPN ) that has substantial advantages over conventional epoxy systems. When the ingredients are combined, it is believed that the silane portion of the aminosilane ingredient is condensed with the polysiloxane ingredient, and the epoxy resides chain extension by reaction with the outstanding amino groups of the polysiloxane, to form a fully cured epoxy polysiloxane polymer composition. In such reaction it is believed that the epoxy resin functions as a crosslinking enhancer, which is added to the crosslinking density of the composition without diminishing the beneficial properties of the polysiloxane. In isolation, the epoxy resin reacts with the aminosilane to form the epoxy polymer chain fragments, and the polysiloxane and aminosilane undergo hydrolytic polycondensation to form a polysiloxane polymer. The reaction kinetics for each polymerization are substantially different, thereby preventing the formation of IPN. For example, the polymerization time of the epoxy resin is about six times that of the polymerization of the polysiloxane polymer. It is believed that the relatively greater amount of time needed to polymerize the non-aromatic epoxy resin is due to the inherent non-reactivity of the non-aromatic epoxy resins, when compared to the high reactivity of the aromatic or unsaturated epoxy resins. In the end, the physical and chemical properties of the epoxy-polysiloxane composition of the present invention are affected by the judicious choice of the epoxy resin, the polysiloxane, the amine and / or aminosilane hardener and the pigment components and / or of the aggregate. An epoxy-polysiloxane composition which is prepared by the combination of a difunctional aminosilane with a non-aromatic epoxy resin, exhibits improved resistance against caustic materials, is resistant to environmental conditions, allows for infinite coating capacity, provides abrasion resistance better than a polyurethane, which is completely unpredictable because the siloxane polymers and epoxy polymers are known to possess terrible resistance to abrasion. The epoxy-polysiloxane compositions of the present invention show unexpected and surprising improvement in resistance against chemical corrosion and environmental conditions, as well as high tensile and compressive strength, and excellent resistance to impact and abrasion. These and other features of the present invention will become more apparent after consideration of the following examples. Reference is made to Table 2 for a description of the ingredients used in Examples 1 to 4. In each example, the ingredients used are combined in the proportions described by weight, in grams.

Table 2 Ingredient Description Eponex 15 13 Shell epoxy resin, equivalent weight = 230 Epodil 757 Cyclohexanedimethanol diglycidyl ether from Pacific Anchor Aroflint 607 Reichold epoxy resin DC-3074 Methoxy functional group polysiloxanes from Dow Corning A- 1 100 Carbide Y- Aminopropyltrimethoxysilane 9632 Aminosilane owned by Carbide Z6020 Aminoethyl-aminopropyltrimethoxysilane from Dow Corning ED-1 17 Aminosilane owned by Wacker Table 2 (continued) Ingredient Description Euredur 3265 Polyamine equivalent weight = 400 of Shering Berlin Ancamine 1942 Polyamine equivalent weight = 70 of Pacific Anchor DCH-99% Diaminocyclohexane of Dupont Araldite R972 Methylene-bis-dianiline equivalent weight = 48 of Ciba Geigy Nuosperse 657 Pigment Moisturizing Agent Tioxide RTC 60 Titanium dioxide F-75 Silica sand mesh 40 Crystal Silica # 70 Silica sand mesh 70 Silcosil 325 US powder silica. Dislon 6500 Thixotrope by King Industries BYK 080 Defoamer by BYK-Chemie Eg emplos Examples 1 to 4 describe the preparation of the resin component of the composition, and the combination of the pigment or aggregate material of the present invention, as used for coating purposes. In each example, the types and proportions of ingredients used to constitute the resin and the pigment mixture are slightly varied. A portion of each resin and pigment mixture as prepared in each example is then combined with various curing and solvent components, in different proportions as shown in Table 3. Each resulting epoxy-polysiloxane composition was tested for curing time. , resistance to environmental conditions, resistance to corrosion and resistance to chemicals, as shown in Table 3.

EXAMPLE 1 A mixture of resin and pigment was prepared by the combination of 385 grams of Eponex 1513 (epoxide resin), 5 grams of Nuosperse 657 (pigment wetting agent), 5 grams of BYK 080 (antifoaming agent), 10 grams of Dislon 6500 (thixotropic agent) and 338 grams of Tioxide RTC60 (titanium dioxide). The ingredients were added to a one-quarter can and assorted to a fineness of Hegman 5 milling, using a dispeller Cowles powered by air motor. This required approximately 20 minutes, after which time 432 grams of DC-3074 (polysiloxane) were added and the combined mixture was then stirred until uniform. The resin mixture had a Brookfield viscosity of approximately 10,000 cP at 20 ° C (70 ° F) and a calculated equivalent weight of 315 grams per equivalent.

EXAMPLE 2 A mixture of resin and pigment was prepared by the combination of 390 grams of Epodil 757 (epoxide resin), 5 grams of Nuosperse 657 (pigment wetting agent), 5 grams of BYK 080 (antifoaming agent), 10 grams of Dislon 6500 (thixotropic agent) and 338 grams of Tioxide RTC 60 (titanium dioxide). The ingredients were added to a one-quarter can and dispersed to a fineness of Hegman grain 5 using a dispeller Cowles powered by air motor. This required approximately 20 minutes after which 432 grams of DC-3074 (polysiloxane) were added and the combined mixture was stirred until uniform. The resin mixture had a Brookfield viscosity of about 3,800 cP at 20 ° C (70 ° F) and a calculated equivalent weight of 265 grams per equivalent.

EXAMPLE 3 The same ingredients and procedures used to prepare the resin and pigment mixture of Example 1 were used, except that 356 grams of Aroflint 607 (epoxide resin) was used instead of 385 grams of Eponex 1513 (epoxide resin). The resin mixture had a Brookfield viscosity of about 6,800 cP at 20 ° C (70 ° F) and a calculated equivalent weight of 338 grams per equivalent.

COMPARATIVE EXAMPLE 4 A mixture of epoxy resin and pigment was prepared by combining 711 grams of Epon 828 (epoxy resin), 5 grams of Nuosperse 657 (pigment moistening agent), 5 grams of BYK 080 (antifoaming agent), 10 grams of Dislon 6500 (thixotropic agent) and 338 grams of Tioxide RTC 60 (titanium dioxide). This comparison example did not include the polysiloxane ingredient. The ingredients were added to a 1-quart can and dispersed to a fine grain fineness of Hegman 5, using a dissolutor Cowles powered by air motor. The mixture was thinned with 100 grams of xylene to reduce the viscosity and then mixed until uniform. The resin mixture had a Brookfield viscosity of approximately 12,000 cP at 20 ° C (70 ° F) and the calculated equivalent weight was 313 grams per equivalent. Three hundred grams of the resin mixture of Example 1 were mixed with 48 grams of Union Carbide's A-1100 (aminopropyltrimethoxysilane) and 20 grams of butyl acetate (organic solvent). The mixture was then applied by spraying to sand-blasting steel test panels using a DeVilbiss spray gun. The coating dried to the touch in less than an hour and was dry in about eight hours. The coating composition showed an initial luster at 60 °, of 90. The resin blends of Examples 1, 2 and 3 and Comparison Example 4 were mixed with the hardeners and solvents shown in Table 3, and applied to the Test panels in a similar way. Compositions prepared according to Table 3 were tested for curing time, resistance to environmental conditions, corrosion resistance and resistance to chemicals according to the following ASTM and industrial test methods: 1. ASTM G53, Once called accelerated natural element corrosive action QUV, is an accelerated test designed to stimulate the deterioration of coatings, caused by sunlight and water such as rain and desiccation. The test panels are exposed to alternating cycles of ultraviolet light and moisture condensation. The degradation is measured by loss of luster or oxidation and blistering on the coating. 2. ASTM B117 measures the corrosion resistance of coated panels exposed to salt spray (fog) under prescribed conditions. The panels are checked periodically and qualified for blistering and oxidation according to ASTM D1654. The rating test method uses a scale of 1 to 10, with 10 indicating no change. 3. The C117 method of Union Carbide, of resistance to chemical products, measures the resistance of the coatings to ten different reagents. One milliliter of each reagent is placed on the test coating and covered with a watch glass. After 24 hours, the reagents are removed and any change is rated on a scale of 1 to 10, with 10 indicating no change, 8 indicating some change, 6 indicating major change, 4 indicating partial failure and 2 indicating indicates complete failure.

Table 3 Epoxy-polysiloxane composition (coating Weight grams Example 1 300 300 300 300 Example 2 300 Example 3 300 Comparison Example 4 300 Butyl Acetate 20 20 20 20 15 20 25 A1 100 48.3 57.9 ED-117 54.9 Y-9632 48.0 45.0 DCH-99% 15.0 Versamid 125 86.3 Test results Thickness of the dry film (mm) 6 6 6 6 6 6 6 Dry to the touch (hours) 1 1 1.2 1.5 1.5 1 1.5 Dry completely (hours) 8 6 10 16 16 12 20 Corrosion by environmental conditions 90 91 90 86 75 22 65, accelerated QUV, 60 ° luster-initial -1 day - 91 91 65 - - 3 -7 days 52 90 66 48 58 13 1 -21 days - 75 36 - - - - Salt mist - (1000 hours) blister formation 10 10 - - - - 10 oxidation 10 10 - - - - 8 Chemical resistance -NaOH (50%) 10 10 - - - - 10 -HCl (conc.) 10 10 - - - - 8 -H2S04 (conc.) 10 10 - - - - 4 -phenol 8 8 - - - - 4 -H3PO4 (conc.) 10 10 - - - - 6 -NH4OH 10 10 - - - - 10 -ethanol 10 10 - - - - 10 -acetic acid (conc.) 8 8 - - - - 4 -eumeno 10 10 - - - - 10 -acetone 10 10 _ - _ 10 The retention of the luster in the accelerated environmental conditions corrosion test QUV, the salt fog test and the chemical spotting tests clearly show that the coatings formed from the epoxy-polysiloxane compositions of the present invention have improved strength against chemical products, corrosion and environmental conditions, when compared to conventional epoxy-based coating compositions. Although the epoxy polysiloxane compositions of the present invention have been described in considerable detail with reference to certain preferred variations thereof, other variations are possible. Therefore, the spirit and scope of the appended claims should not be limited to the preferred variations described herein.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (18)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A cross-linked epoxy-polysiloxane polymer composition, characterized in that it is prepared by the combination of: water; with a polysiloxane that has the formula wherein each Ri is selected from the group consisting of the hydroxyl group and the alkyl, aryl and alkoxy groups having up to six carbon atoms, each R 2 is selected from the group consisting of hydrogen and the alkyl and aryl groups having up to six carbon atoms. carbon and, wherein n is selected such that the molecular weight for the polysiloxane is in the range of about 400 to 10,000; a non-aromatic epoxy resin having more than one 1,2-epoxide group per molecule, with an epoxide equivalent weight in the range of 100 to about 5,000; and a sufficient amount of an aminosilane hardening component having two amine hydrogens to react with the epoxide groups in the epoxy resin, to form epoxy chain polymers, and to react with the polysiloxane to form polysiloxane polymers, wherein the polymers Epoxy chain and the polysiloxane polymers are copolymerized to form a cured cross-linked epoxy-polysiloxane polymer composition.

2. The composition according to claim 1, characterized in that the non-aromatic epoxide resin is selected from the group consisting of cycloaliphatic epoxy resins consisting of hydrogenated cyclohexanedimethanol and diglycidyl ethers of the hydrogenated Bisphenol A epoxide resins.

3. The composition according to claim 1, characterized in that the aminosilane has the general formula Y - Yes (0-X) 3 where Y is H (HNR) a and where a is one, R is a difunctional organic radical independently selected from the group consisting of the aryl, alkyl, dialkylaryl, alkoxyalkyl, and cycloalkyl radicals, and wherein X is limited to the alkyl, hydroxyalkyl groups , alkoxyalkyl or hydroxyalkoxyalkyl containing less than about six carbon atoms.

4. The composition according to claim 1, characterized in that the composition additionally comprises at least one metal catalyst to facilitate curing at room temperature, wherein the catalyst is selected from the group consisting of zinc, manganese, zirconium, titanium, cobalt, iron , lead, and tin, each in the form of octonates, neodecanes, or naphthatates.

5. The composition according to claim 1, characterized in that it comprises at least one additional ingredient selected from the group consisting of rheology modifiers, plasticizers, antifoaming agents, thixotropic agents, pigment moistening agents, bituminous and asphalt extenders, antiaging agents, diluents, UV light stabilizers, air release agents, dispersion aids, and mixtures thereof.

6. The composition according to claim 1, characterized in that it further comprises a pigment or aggregate material having a fine particle size selected from the group consisting of organic and inorganic color pigments, at least 90 weight percent of the pigment having a larger particle size of North American mesh no. 325

7. The composition according to claim 1, characterized in that it comprises epoxy resin in the range of about 10 to 60 weight percent, 15 to 60 weight percent of polysiloxane, and 5 to 40 weight percent of aminosilane hardener, based on the total weight of the composition.

8. An epoxy-polysiloxane polymer composition, characterized in that it is prepared by the combination of: a polysiloxane selected from the group consisting of polysiloxanes with alkoxy and silanol functional group having a molecular weight in the range of about 400 to 10,000; with non-aromatic epoxy resin having more than one epoxide group per molecule; a sufficient amount of an aminosilane hardening component having two amine hydrogens providing amine in the range of 0.7 to 1.2 equivalent weight per equivalent weight of epoxide having the general formula Y - Si - (OX) 3 where Y is H (HNR) a and where a is one, R is a difunctional organic radical independently selected from the group consisting of the aryl, alkyl, dialkylaryl, alkoxyalkyl, and cycloalkyl radicals, and where X is limited to alkyl, hydroxyalkyl, alkoxyalkyl or hydroxyalkoxyalkyl groups containing less than about six carbon atoms, wherein the aminosilane hardener reacts with the epoxy to form epoxy chain polymers, and reacts with the polysiloxane to form polysiloxane polymers which are copolymerized with the epoxy chain polymers to form a cross-linked epoxy-polysiloxane composition; An organotin catalyst; and A sufficient amount of water to facilitate hydrolysis and polycondensation reactions to form the fully cured crosslinked epoxy polysiloxane polymer composition at room temperature.

9. The composition according to claim 8, characterized in that it comprises epoxy resin in the range of about 10 to 60 weight percent, based on the total weight of the composition, wherein the epoxy resin has an epoxide equivalent weight in the range from 100 to 5,000.

10. The composition according to claim 9, characterized in that the epoxy resin is selected from the group of cycloaliphatic epoxy resins consisting of hydrogenated cyclohexanedimethanol and diglycidyl ethers of hydrogenated Bisphenol A epoxide resins.

11. The composition according to claim 8, characterized in that it comprises polysiloxane in the range of 15 to 60 weight percent, based on the total weight of the composition, wherein the polysiloxane has the formula wherein each Ri is selected from the group consisting of the hydroxyl group and the alkyl, aryl and alkoxy groups having up to six carbon atoms, each R 2 is selected from the group consisting of hydrogen and the alkyl and aryl groups having up to six carbon atoms. carbon and, wherein n is selected so that the molecular weight for the polysiloxane is greater than about 400.

12. The composition according to claim 8, characterized in that it further comprises additives up to about ten percent by weight of the total composition, wherein the additives are selected from the group consisting of flow modifiers, rheology modifiers, plasticizers, antifoaming agents. , thixotropic agents, pigment wetting agents, bituminous and asphaltic extenders, antiaging agents, diluents, UV light stabilizers, air release agents, and dispersion aids.

13. The composition according to claim 8, characterized in that it further comprises a pigment or aggregate material of fine particle size selected from the group consisting of organic and inorganic colored pigments, wherein the aggregate material comprises at least 90 weight percent of aggregate that has a North American mesh particle size greater than 325, based on the total weight of the aggregate material.

14. An epoxy-polysiloxane polymeric polymer network composition of non-interpenetration, characterized in that it is prepared by the combination of: water; with a polysiloxane that has the formula wherein each Ri is selected from the group consisting of the hydroxyl group and the alkyl, aryl and alkoxy groups having up to six carbon atoms, each R 2 is selected from the group consisting of hydrogen and the alkyl and aryl groups having up to six carbon atoms. carbon and, wherein n is selected such that the molecular weight for the polysiloxane is in the range of about 400 to 10,000; a non-aromatic epoxy resin having more than one 1,2-epoxide group per molecule, with an epoxide equivalent weight in the range of 100 to about 5,000; and a stoichiometric amount of an aminosilane hardening component to react with the epoxy resin, to form epoxy resin polymers and with the polysiloxane to form polysiloxane polymers, and has the general formula Y - Yes - (0-X) 3 where Y is H (HNR) a and where a is one, R is a difunctional organic radical independently selected from the group consisting of the aryl, alkyl, dialkylaryl, alkoxyalkyl, and cycloalkyl radicals, and wherein X is limited to the alkyl, hydroxyalkyl groups , alkoxyalkyl or hydroxyalkoxyalkyl containing less than about six carbon atoms; and wherein the epoxy resin polymers and the polysiloxane polymers react together to form an epoxy-polysiloxane polymer of cross-linked non-interpenetrating polymer network.

15. A method for the preparation of a fully curing epoxy-polysiloxane polymeric epoxy-polysiloxane composition characterized in the method comprising the steps of: forming a resin component by combining: a non-aromatic epoxy resin; a polysiloxane selected from the group consisting of polysiloxanes with alkoxy and silanol functional group having a molecular weight in the range of 400 to 10,000; with water; and curing the resin component at room temperature by adding thereto: an aminosilane with two active hydrogens that react with the epoxide resin to form epoxy chain polymers and with the polysiloxane to form polysiloxane polymers, wherein the polymers Epoxy chain reacts with the polysiloxane polymers to form a fully cured cross-linked epoxy polysiloxane polymer; And an organotin catalyst to facilitate the curing of the resin component at room temperature.

16. A method according to claim 15, characterized in that during the step of forming the resin component one or more ingredients are added which are selected from the group consisting of pigments, aggregates, or flow modifiers, rheology modifiers, plasticizers, antifoam agents, thixotropic agents, pigment wetting agents, bituminous and asphaltic extenders, antiaging agents, diluents, UV stabilizers, air release agents and dispersion aids.

17. A method for making a fully cured epoxy polysiloxane polymer composition, characterized in that the method comprises the steps of: forming a resin component by combining: a polysiloxane having the formula wherein each Ri is selected from the group consisting of the hydroxyl group and the alkyl, aryl and alkoxy groups having up to six carbon atoms, each R 2 is selected from the group consisting of hydrogen and the alkyl and aryl groups having up to six carbon atoms. carbon and, wherein n is selected such that the molecular weight for the polysiloxane is in the range of about 400 to 10,000; a non-aromatic epoxy resin having more than one 1,2-epoxide group per molecule, with an epoxide equivalent weight in the range of 100 to about 5,000; and water; the curing of the resin component at room temperature when adding to it: an organotin catalyst; and an aminosilane with two active hydrogens that is condensed through its silane groups with the polysiloxane, whereby the epoxy resin undergoes chain extension by reaction with the amine groups in the polysiloxane, to form a fully cured epoxy-polysiloxane polymer. .

18. A cross-linked epoxy-polysiloxane polymer composition characterized in that it is prepared by combining: a polysiloxane from the group consisting of polysiloxanes with alkoxy and silanol functional group having a molecular weight in the range of 400 to 10,000; with a non-aromatic epoxy resin having more than one epoxide group per molecule; a sufficient amount of an aminosilane ingredient to provide amine in the range of 0.7 to 1.2 equivalent weights of amine, by an equivalent weight of epoxide to react with the epoxy to form epoxy chain polymers, and with the polysiloxane to form polymers of polysiloxane which are copolymerized to form a cross-linked epoxy-polysiloxane copolymer composition.