MXPA01000283A - Partial interpenetrating networks of polymers - Google Patents

Abstract

A process for producing a coating composition for use over chalky substrates comprising a partial interpenetrating network of a polyurethane component and a waterborne polymer component, wherein the polyurethane component is prepared in the presence of the waterborne polymer component.

Description

PARTIALLY INTERPENETRANT POLYMER NETS FIELD OF THE INVENTION This invention relates to improved resins and polymers for use in both paints and coatings, and in residential architectural exterior paints and coatings, particularly with coatings having utility over weathered and powdered substrates, such as brick, wood , vinyl and aluminum deck boards.

BACKGROUND OF THE INVENTION A dusty substrate is one in which the elements (such as sun, rain, snow, heat, etc.) have degraded the integrity of the paint film to such an extent that it breaks up and a dust is evolved. fine that stays on the surface of the structure or the housing building. This powder consists of pigment, binder, additives, etc., which due to the degradation of the paint film are no longer part of a coherent film. This degraded film does not provide good protection to the underlying substrate. Furthermore, these powdered substrates are generally not the preferred surfaces for the application of a new paint layer, since the powder will adversely affect the adhesion characteristics of the new paint on the substrate. U.S. Patent No. 4,722,965 discloses a latex polymer comprising a major amount of an alkyl acrylate and / or alkyl methacrylate and a minor amount of a secondary amine, this latex polymer can be mixed with copolymer acetate / acrylic coatings to form a latex coating composition having improved powder adhesion properties. European Patent Application 94309136.3 discloses the use of a polymer blend of a latex, a resin having an acid functional group and which is soluble in alkali and an aminosilane to provide adhesion of the coatings on powdery substrates. U.S. Patent No. 5,202,378 discloses an outdoor latex paint having improved adhesion over dust, wherein the latex paint is based on a film-forming polymer binder containing minor amounts of acrylate or copolymerized fatty acid methacrylate, such as lauryl or stearyl methacrylate. Currently, there are various latex and alkyd paints, which are available commercially, which claim to be suitable for use on powdery substrates. All coatings that are currently available have limitations, either in their adhesion properties or in other paint properties. The present invention offers better adhesion to powdered substrates and other substrates than coatings that are currently available.

SUMMARY OF THE INVENTION The present invention comprises polymers and coatings prepared therefrom, which have exceptional adhesion to powdery substrates, which makes them ideal coatings for use in outdoor paints. The present invention comprises a polymer network, ie, a polymer network, also referred to herein, as a "partially interpenetrating network" or "PIPN" which comprises at least two components: a polyurethane component and a polymer component carried in water, wherein the polyurethane component is prepared, at least partially, in the presence of the polymer component carried in water and, where one or both of the components They may contain functional groups that allow them to cure or crosslink, either alone or with the other component, after application to the substrate. The preparation of the polyurethane component in the presence of the polymer component carried in water ensures a partially interpenetrating network of two polymers which is not only physically different from the cold mixture of two polymers prepared separately, but is also functionally superior to said cold mix as regards its adhesion to powdery substrates and other substrates, such as galvanized metal, chipboard, wood, concrete, plastic, leather, vinyl and substrates coated with glossy alkyd paint and aged. While there are several different variants and preferred embodiments of the present invention, essential to the success of the invention is the preparation of two components, a polymeric component carried in water and a polyurethane component. In one embodiment, the polyurethane is prepared as a prepolymer which is neutralized and dispersed in a latex polymer composition and subsequently subjected to chain extension in the presence of the latex composition to create a network of the two polymers that is much more integrated than a physical mixture of the two separate components. The alternative and preferred embodiments of the present invention will now be described more fully, allowing the person in charge of the formulations to incorporate functional groups in either or both of the components, that of polyurethane and that of the polymer carried in water, which allows that the components cure or reticulate (either individually or with each other) after application to the substrate. The polymer network and the coatings containing the polymer network produced by the present invention have particular utility in powdered substrates including wood, concrete, cement, brick, vinyl and previously painted aluminum deck boards, as well as the like. They can also be applied to metal, concrete, wood, plastic, leather, vinyl and other non-dusty substrates.

DETAILED DESCRIPTION OF THE INVENTION The compositions of this invention are polymeric systems comprising a polyurethane component and at least one polymeric component carried in water, wherein the polyurethane component is partially prepared in the presence of the polymeric component carried in water to produce a final polymer network that is highly integrated and that has better performance characteristics than the mere physical mix of the individual components. The compositions of this invention are polymer networks which, * - - ~ l! . in one sense, they can be described as stable dispersions of polyurethane polymers prepared at least partially in the presence of a polymeric medium carried in water. However, unlike the physical mixture of a dispersion of preformed polyurethane polymer and a polymer carried in preformed water, the partial preparation of the polyurethane polymer in the presence of the polymer carried in water results in a network of the two components which is different from the physical mixture, both in its physical properties and in its performance properties. Depending on the functional groups that are present in the polyurethane component, on the polymer component carried in water or both, the two components can be crosslinked (either together or individually) after application to the substrate. The composition of the present invention may contain two or more components carried in water, such as, for example, a latex and a silicone emulsion. Other polymeric components carried in water may include water-reducible alkyds, alkyd emulsions, acrylic polymers, polyester emulsions, fluoropolymer emulsions, polyurethane-acrylic dispersions, silicone emulsions, polyethylene emulsions, polyurethane dispersions and polyamide dispersions.

Polyurethane Component As described above, the polyurethane component is generally prepared as a prepolymer that is dispersed in the polymeric component carried in water, after which it is further reacted to produce the final product of this invention. The polyurethane prepolymer is preferably prepared from ingredients that produce a predominantly linear prepolymer, i.e., a prepolymer prepared from substantially bifunctional reactants. The polyurethane prepolymer compositions of this invention are generally produced by first reacting an active hydrogen-containing composition with a material having an isocyanate functional group. The material with the isocyanate functional group is preferably a material having the functional group diisocyanate, selected from the group of: aromatic, cycloaliphatic or aliphatic isocyanates. Examples of suitable isocyanates include 1,6-hexamethylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, isophorone. diisocyanate, cyclohexane-1,4-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, p-xylylene diisocyanate, meta-1,1,3,3-tetramethylxyl diisocyanate and mixtures thereof. Small amounts of trifunctional isocyanates can be used, such as a trimer of hexamethylene diisocyanate in the form of isocyanurate or biuret and the trimer of isophorone diisocyanate. Preferred diisocyanates include 4,4'-dicyclohexylmethane diisocyanate, meta-1,1,3,3-tetramethylxylylene diisocyanate, isophorone diisocyanate and mixtures thereof. What is most preferred is a combination of 4, '-dicyclohexylmethane diisocyanate and meta1, 1,3,3-tetramethylxylylene diisocyanate. When a mixture of two or more isocyanates is used, the ratio of NCO equivalents to those contributed by the individual isocyanates is not critical. The composition containing active hydrogen that reacts with the isocyanate has, preferably, two functional groups with respect to the isocyanate groups, ie they have two active hydrogen atoms as determined by the Zerewitinoff method. Active hydrogens include hydrogen atoms bonded to oxygen, nitrogen or sulfur and, thus, useful compounds include those having at least two of the -OH, -SH, -NH and -NH2 groups. Examples of these compounds include diols, diamines, amino alcohols and mercaptans. The composition containing active hydrogen is preferably a diol selected from the group consisting of ^ ma ^ - ti? M ti ^ áii ^^^ i ^^^^^^^^^^^^^^ M ^^^^ polyester diols, polyether diols, polyacetal diols, polyamide diols, polyester polyamide diols, poly (alkylene ether) diols, polythioether diols and polycarbonate diols. Suitable polyether diols are, for example, the condensation products of ethylene oxide, propylene oxide, butylene oxide or tetrahydrofuran and their copolymerization, graft or block polymerization products, such as mixed ethylene oxide, condensates. of propylene oxide and the graft polymerization products of the reaction of olefins under high pressure with the aforementioned alkylene oxide condensates. Suitable polyethers are prepared by condensation of the said alkylene oxides with polyhydric alcohols, such as ethylene glycol, 1,2-propylene glycol and 1,4-butane diol. The polyester diols, polyester amide diols and suitable polyamide diols are preferably saturated and are obtained, for example, from the reaction of saturated or unsaturated polycarboxylic acids, with saturated or unsaturated polyhydric alcohols. Suitable carboxylic acids for preparing these compounds include, for example, adipic acid, succinic acid, phthalic acid, terephthalic acid and maleic acid. Suitable polyhydric alcohols for preparing diols of --Ml -? ----------------- -------- ßSÉÉ & polyester include, for example, ethylene glycol, 1,2-propylene glycol, 1, 4 -butanediol, neopentyl glycol, hexanediol and trimethylolpropane. A suitable amino alcohol for preparing polyester amide diols is, for example, ethanolamine. Suitable diamines for preparing polyester amide diols and polyamide diols are, for example, ethylenediamine and hexamethylenediamine. Suitable polyacetals can be prepared from, for example, 1,4-butanediol or hexanediol and formaldehyde. Suitable polythioether diols can be prepared, for example, by the condensation of thiodiglycol with ethylene oxide, propylene oxide, butylene oxide or tetrahydrofuran. Additional useful diols include Bisphenol A, polybutadiene-based diols, polysiloxane-based diols and fluorinated diols. The most preferred bifunctional active materials containing active hydrogen are a combination of: 1) polyester diols formed from the reaction of saturated and unsaturated dihydric alcohols, such as ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,4 -butenediol, 1,6-hexanediol, furan dimethanol and cyclohexanedimethanol with saturated and unsaturated polycarboxylic acids, such as maleic acid, fumaric acid, itaconic acid, succinic acid, goes "to-" "• *» "-« ** »•• glutaric acid, adipic acid, isophthalic acid, terephthalic acid, phthalic anhydride, dimethyl terephthalate, dimeric acids and the like; and 2) hydrophilic groups containing diol. A preferred polyester diol is Rucoflex ™ 1015-120 (a mixture of polyether diols based on neopentyl glycol, hexanediol and adipic acid, which can be obtained commercially from Ruco Polymer Corporation). A particularly preferred diol containing hydrophilic groups is dimethylolpropionic acid. When used, these two diols are preferably present in percentages such that the Rucoflex ™ material contributes approximately between 30% and 70% of the OH functional group of the total materials. As the examples demonstrate hereinafter, a preferred embodiment comprises Rucoflex ™ 1015-120, trimethylolpropane, dimethylolpropionic acid and cyclohexane dimethanol. Although it is preferred to use bifunctional compounds containing active hydrogen, small amounts of trifunctional compounds and with a greater number of functional groups can be used. Examples of these compounds with a greater number of functional groups include trimethylolpropane, pentaerythritol, polyester triols and polyether triols. Large amounts of these compounds with a greater number of functional groups will create in solution an undesirable cross-linked non-linear prepolymer. In a preferred embodiment, the polyurethane component contains at least one functional group that allows the polyurethane component to be further crosslinked (in auto-oxidative or otherwise) once the composition has been applied to the substrate and is exposed to the drying conditions of the polyurethane. ambient air, usually associated with house paints. During the preparation of a polyurethane prepolymer with the isocyanate functional group, the preferred proportion of the total of active hydrogen-isocyanate-containing materials must be such that there is an excess of the isocyanate functional group with respect to the active hydrogen functional group. Preferably the ratio of molar equivalents of NCO to total active hydrogen should be approximately between 1.01: 1 and 2.0: 1; preferably approximately between 1.01: 1 and 1.7: 1. To prepare a polyurethane prepolymer with the hydroxy functional group, there must be an excess of the hydroxy functional group with respect to the isocyanate functional group. Optionally and preferably, during the reaction is present up to about 0.06%, preferably about 0.01% to 0.04% (by weight, based on the total solids of the compositions containing active hydrogen and diisocyanate) of a catalyst such as dibutyltin dilaurate , tin octoate and the like. To ensure that the polyurethane prepolymer is dispersible in an aqueous medium, such as in a latex medium, pendant or suspended ionizable groups are incorporated into the prepolymer and then subsequently ionized. Useful ionizable groups include pendant or pendant groups such as the carboxylate, sulfonate, sulfate, phosphonate and / or phosphate groups, located along the polymer backbone. Preferred carboxylate groups are those that are derived by preparing the polyurethane prepolymer from an active hydrogen-containing composition and having a carboxyl group. For example, diols, diamines and bifunctional diols containing a carboxyl group are useful. The preferred composition containing active hydrogen with the carboxy functional group is dimethylolpropionic acid. The polyurethane prepolymer must contain a sufficient amount of the carboxyl groups, which are ionized by neutralization to render the polyurethane prepolymer dispersible. Preferably, the contribution of part of the active hydrogen-containing compositions having ionizable groups is between about 1% and 10% of the solids by weight of the polyurethane prepolymer.

The ionizable groups of the polyurethane prepolymer are converted by combining the prepolymer with water containing a tertiary amine. Tertiary amines which can be used include triethylamine, trimethylamine, triisopropylamine, tributylamine, triethylenediamine, N, N-dimethyl-cyclohexylamine, N, N-dimethylstearylamine, N, N-dimethylaniline, N-methylmorpholine, N-ethylmorpholine, N-methylpiperazine, N-methylpyrrolidine, N, N-dimethyl-ethanolamine, N, N-diethyl-ethanolamine, triethanolamine, N-methyldiethanolamine, dimethylaminopropanol, 2-methoxyethyldimethylamine, N-hydroxyethylpiperazine, 5-diethylamino-2-pentanone and mixtures thereof and scatter. The amount of added tertiary amine must be sufficient to neutralize at least about 90% of the ionic groups present in solution. Preferably, the tertiary amine is added in an amount sufficient to neutralize 100% of the ionic groups. Other weak bases can be used to neutralize the ionic groups, although tertiary amines are preferred, because they do not react with the free isocyanate groups of the prepolymer. The preparation of the polyurethane prepolymer is usually carried out by charging the active hydrogen-containing composition with the catalyst into a reaction vessel, heating the content to a "V - ^ - a ------ temperature of between about 85 ° C and 100 ° C and adding, either by continuous or stepwise addition in a period of time, preferably approximately between 0.5 hours and 1.5 hours The materials with the isocyanate functional group may optionally be present in a solvent, such as n-methyl-2-pyrrolidone, dimethylformamide, methyl ethyl ketone (MEK), toluene and mixtures thereof in an amount which it varies up to about 20% by weight, based on the total weight of the materials present in the reaction vessel.After completing the addition of the isocyanate materials, the temperature of the reaction vessel is maintained between approximately 85 ° and 100 °. C, for about 3 to 4.5 hours The percentage of residual isocyanate can be determined using any means well known in the art At this point, the polyurethane prepolymer is now formed and is ready for the reaction additional, in accordance with this invention. The prepolymer is dispersed in water containing a tertiary amine, such as, for example, triethylamine, which neutralizes the ionic groups of the prepolymer. Once the polyurethane is dispersed in water, the dispersion is ready for incorporation of the polymeric component carried in water. In general, the weight ratio of the polyurethane prepolymer component to the polymer component carried in water, in general, is in the range of about 1:99 to 99: 1, preferably about 1: 4 to 1: 1. . To extend the polyurethane prepolymer chain and convert it into a PIPN in the presence of the polymer component carried in water, a compound having a functional group capable of extending the polyurethane prepolymer chain, such as a polyol, an amino alcohol, is used. , an aliphatic, alicyclic, aromatic or heterocyclic primary or secondary amine or diamine, a silicone with the amine functional group or a silane with the amine functional group. Water-soluble chain extenders are preferred. Examples of suitable chain extenders include ethylene diamine, propylene diamine, butylene diamine, hexamethylenediamine, cyclohexylenediamine, piperazine, 2-methyl piperazine, isophorone diamine, phenylenediamine, tolylenediamine, xylylenediamine, hydrazine, dimethylhydrazine, adipic dihydrazide, ethylene glycol, di, tri, and tetraethylene glycol, propane 1,2-diol, propane 1,3-diol, neopentyl glycol and mixtures thereof, equivalents thereof and the like in an amount sufficient to react with up to at least 90% of the theoretical amount of the NCO functional group residual, it is added in general to the composition to extend the polyurethane chain. Chain extenders having a number of functional groups greater than 2, such as, for example, diethylenetriamine, may also be included, although they should be limited to a small amount to avoid creating a composition that is highly crosslinked. If the polyurethane prepolymer has a hydroxy functional group, a dispersible or water-emulsifiable polyisocyanate can be used as the chain extender. If the polyurethane prepolymer has an acetoacetoxy functional group, a polyamine, a polyaldehyde or a dispersible or water-emulsifiable polyisocyanate can be used as the chain extender. If the polyurethane prepolymer contains N-methylol functional groups, a dispersible or water-emulsifiable polyisocyanate can be used as the chain extender. The creation of a partially interpenetrating network by extending the polyurethane prepolymer chain in the presence of a fully prepared water-borne polymer composition creates a final composition that physically is not equal to the physical cold mixture of a similar polyurethane dispersion and a polymer carried in similar water. As discussed above, the dispersing medium of the polyurethane prepolymer is preferably water to which the polymer component carried in water is subsequently added. This can be a combination of the polymeric component carried in water and additional water.

Variations in the structure of the polyurethane In one embodiment, the polyurethane component of the present invention contains ingredients that allow it to be cured in auto-oxidative form after application to the substrate, when exposed to the conditions of curing to ambient air, normally associated with architectural paints and coatings. In particular, during or after the preparation of the polyurethane prepolymer, although before the extension of the prepolymer chain into the polymeric component carried in water, the compositions which are attached to the main chain of the polyurethane can be added to the composition of the polyurethane. prepolymer Each of these compositions is reacted directly with the polyurethane backbone, but remains unreacted during the chain extension process and also remains unreacted during normal storage of the final product. However, with the application of the product to the substrate and the exposure to the drying conditions normally associated with house paint, these added functional groups cure the polyurethane component in auto-oxidative form. Preferred compositions that allow this post-application crosslinking, ie post-application, include .------- g-k.-M -.- J - »» »---, .-" fl ^ & -a-fe- ^ - ^^ s-sgte .- »----- *. £ &&&c > compositions containing active hydrogen that are monofunctional or bifunctional with respect to the isocyanates. Some of these materials containing active hydrogen include fatty amines, allylamines, diallylamines, ethoxylated allylamines, ethoxylated allyl alcohols, fatty alcohols, allyl alcohols, trimethylol propane mono and diallyl ether, hydroxyethyl acrylate, hydroxyethyl methacrylate, mono and diglycerides obtained by alcoholysis of oils drying with polyols or the reaction of drying fatty acids with polyols, acetoacetate-containing materials, such as the adduct of trimethylolpropane with t-butylacetoacetate, the direct introduction of the acetoacetate functional group into the polyurethane prepolymer by reaction with t-butylacetoacetate or diketene and the reaction of the main chain with drying oils having anhydride functional groups, either in the preparation stage of the prepolymer or in the extension of the chain. Polyurethane polymer backbones can also be added to the backbone of the polyurethane polymer which cure by the condensation mechanism, for example, by reacting the polyurethane prepolymer with a di or trialkoxysilane having the amine functional group, with a di or trialkoxysilane having the diamine functional group or with a di or trialkoxysilane having the isocyanate functional group. Post-crosslinking functional groups can also be prepared by treating the polyurethane prepolymer with adipic dihydrazide and formaldehyde. Additionally, the polyurethane prepolymer can be modified to include post-crosslinking functional groups by incorporating oils with the epoxy, di or trialkoxysilane functional group with the epoxy or di or trialkoxysilane functional group with the amine or diamine functional group in the extension step of the chain. Crosslinking agents or aminoplast crosslinkers such as hexametoxymelamine or those having a high content of N-methylol or imino groups may be added in the chain extension step to introduce crosslinking by condensation.

Polymer Component Carried in Water Suitable for use as the waterborne polymer component of the invention, is any polymer carried in water that does not have functional groups that are reactive with the NCO functional group of the polyurethane prepolymer or with the polyamine chain extender or polyhydroxy, as well as with the carboxyl groups and with any functional groups in the prepolymer. These polymers carried in water include emulsions of s * 3 * latex, acrylic polymers, polyester emulsions, water-reducible alkyd polymers, alkyd-acrylic dispersions, alkyd emulsions, fluoropolymer emulsions, silicone emulsions, polyethylene emulsions, polyurethane dispersions, polyamide dispersions and dispersions of polyurethane-acrylic. A polymer carried in water useful and preferred in the present invention can be almost any latex composition that is suitable for use as a paint and / or coating, preferably a latex formulated to be an exterior paint and / or coating. Conventional latex polymers were prepared by polymerizing at least one ethylenically unsaturated monomer in water, using surfactants and water soluble initiators. Typical ethylenically unsaturated monomers include vinyl monomers, acrylic monomers, allylic monomers, acrylamide monomers and mono- and dicarboxylic unsaturated acids. Vinyl esters include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isopropyl acetate, vinyl neodeconate and similar vinyl esters; vinyl halides include vinyl chloride, vinyl fluoride and vinylidene chloride; Vinyl aromatic hydrocarbons include styrene, α-methylstyrene and similar lower alkyl styrenes. Acrylic monomers include monomers such as lower alkyl esters of acrylic or methacrylic acid having an alkyl ester moiety containing from 1 to 12 carbon atoms, as well as aromatic derivatives of acrylic and methacrylic acid. Useful acrylic monomers include, for example, acrylic and methacrylic acid, methacrylate and methacrylate, ethylacrylate and methacrylate, butylacrylate and methacrylate, propylacrylate and methacrylate, 2-ethylhexylacrylate and methacrylate, cyclohexyl acrylate and methacrylate, decylacrylate and methacrylate, isodecyl acrylate and methacrylate, and benzyl acrylate and methacrylate. The preparation of latex compositions is well known in the art of painting and coating. Any of the well-known free radical emulsion polymerization techniques for formulating the latex polymers can be used in the present invention. Polymerization techniques suitable for use herein are taught in U.S. Patent No. 5, 486, 576, incorporated by reference herein.

Coating formulations Once dispersed in the dispersion medium, the composition can be modified with other standard ingredients commonly used to formulate outdoor paints in homes. For example, the dispersions of this $. -. invention can be combined with other ingredients such as pigments, extenders, dispersants, surfactants, colorants, paraffins, waxes, UV stabilizers, rheology modifiers, biocides, fungicides and other conventional additives. Dispersions of dyes and pigments, when used, are usually added in amounts of up to about 15% by volume of the total composition.

EXAMPLES The following examples demonstrate the methods of preparation of the compositions of this invention. They also demonstrate the preparation of representative polyurethane components and representative polymeric waterborne components. The examples are intended to be representative of the formulations that can be prepared and are not intended to limit the scope of the invention.

EXAMPLE 1 Preparation of a polyurethane-acrylic PIPN with subsequent crosslinking A reaction vessel equipped with a nitrogen blanket was charged with 30.0 g of n-methyl pyrrolidone, 180 g of the polyester diol mixture Rucoflex ™ 1015-120, 25.0 g of dimethylolpropionic acid, 6. 0 g of trimethylolpropane, 10.0 g of 1,4-cyclohexanedimethanol and about 1 g of dibutyl tin dilaurate (10% solution in n-methyl pyrrolidone). The contents of the vessel were stirred and the temperature was increased to about 90 ° C. The addition then began in 30 minutes of 146.52 g of meta-1, 1,3,3-tetramethylxylylene diisocyanate (m-TMXDI) and 63.35 g of isophorone diisocyanate (IPDI). The content of the container was maintained for 3.5 to 4 hours or until the theoretical isocyanate value was reached and then 12.5 g of primary soy amine (Adogen 115D of Witco) were added in a period of 15 minutes and the reaction was then maintained under these conditions for 15 minutes to create a polyurethane prepolymer. The polyurethane prepolymer was added to a vessel containing 980.7 g of water and 17.8 g of triethylamine and dispersed well. To the vessel was then added an acrylic latex, which can be obtained commercially, in an amount of 2216.9 g, containing 50% butylacrylate, 48% methyl methacrylate and 2% methacrylic acid and having a solids content of 55% to 60%. Stirring was continued for an additional 3-4 minutes at room temperature (about 25 ° C), after which, 17.6 g of ethylenediamine in 25 g of water was added to the vessel over a period of five minutes to extend the prepolymer chain to time that remains cold to the dispersion. The contents of the container were then dispersed for an additional 45 minutes.

EXAMPLE 2 Preparation of a polyurethane-acrylic PIPN without subsequent cross-linking A reaction vessel equipped with a nitrogen blanket was charged with 40.0 g of n-methyl pyrrolidone, 180 g of Rucoflex ™ 1015-120, 24.0 g of dimethylolpropionic acid, 4.0 g of trimethylolpropane, 10.0 g of 1,4-cyclohexane dimethanol and approximately 1.0 g of dibutyl tin dilaurate (10% solution in n-methyl pyrrolidinone). The contents of the vessel were stirred and the temperature was increased to about 90 ° C. The addition then began in 30-40 minutes of 140.54 g of m-TMXDI and 696.62 g of 4,4 '-dicyclohexylmethane diisocyanate (Desmodur W). The contents of the container were maintained for 3.5 to 4 hours to create a polyurethane prepolymer. The polyurethane prepolymer was then added to a vessel containing 872.9 g of water and 17.2 g of triethylamine and dispersed for three minutes. The acrylic latex of Example 1, which can be obtained commercially, is then added to the container in a -ugly--". amount of 2140.9 g. Stirring was continued for an additional 3-4 minutes at room temperature (approximately 25 ° C), after which, 18.0 g of ethylenediamine in 25 g of water were added to the vessel over a period of five minutes to extend the prepolymer chain to the time that remains cold to the dispersion. The contents of the container were then dispersed for an additional 45 minutes.

EXAMPLE 3 Preparation of a polyurethane-acrylic PIPN with subsequent crosslinking A reaction vessel equipped with a nitrogen blanket was charged with 30.0 g of n-methyl pyrrolidone, 311.13 g of the Rucoflex ™ 1015-120 polyester diol blend, 23.0 g of dimethylolpropionic acid, 3.0 g of trimethylolpropane, 5.0 g of 1,4-cyclohexane dimethanol and about 1.0 g of dibutyl tin dilaurate (10% solution in n-methyl pyrrolidinone). The contents of the vessel were stirred and the temperature was increased to about 90 ° C. The addition then started in 30-40 minutes of 153.84 g of meta-1, 1,3,3-tetramethylxylylene dusocyanate (m-TMXDI) and 39.06 g of isophorone diisocyanate (IPDI) and the contents of the container were maintained for 3.5 to 4 minutes. hours. 2.18 g of aminopropyl triethoxy silane were then added over a period of 5 minutes and the reaction was maintained under these conditions for 15 to 20 minutes to create a polyurethane prepolymer. The polyurethane prepolymer was then added to a vessel containing 891.56 of water and 16.8 g of triethylamine and dispersed for three minutes. To the vessel was added acrylic latex of Example 1, which can be obtained in commercial form, in an amount of 3581.4 g. Stirring was continued for an additional 3-4 minutes at room temperature (about 25 ° C), after which, 12.2 g of ethylenediamine in 22 g of water were added to the vessel over a period of five minutes to extend the prepolymer chain to the time that remains cold to the dispersion. The contents of the container were then dispersed for an additional 45 minutes.

EXAMPLE 4 Preparation of a polyurethane-vinyl acrylic PIPN with subsequent crosslinking To a vessel equipped with a nitrogen blanket was charged 30.0 g of n-methyl pyrrolidone, 180 g of the Rucoflex ™ 1015-120 polyester diol blend, 25.0 g of dimethylolpropionic acid, 6.0 g of trimethylolpropane, 10.0 g of 1,4-cyclohexane dimethanol and about 1.0 g of dibutyl tin dilaurate (10% solution in n-methyl pyrrolidinone). The stirring then started and the temperature was increased to about 90 ° C. In a period of 30-40 minutes, 146.52 g of meta-1, 1,3,3-tetramethylxylylene diisocyanate (m-TMXDI) and 63.35 g of isophorone diisocyanate (IPDI) were then added. The content of the container was maintained for 3.5 to 4 hours and then 12.5 g of primary soy amine (Adogen 115D from Witco) were added in a period of 15 minutes. The reaction was maintained under these conditions for 30 to 60 minutes to create a polyurethane prepolymer. The polyurethane prepolymer was added to a vessel containing 703 g of water and 17.8 g of triethylamine and dispersed for three minutes. A vinyl acrylic latex, which can be obtained commercially, in an amount of 2418.4 g, consisting of 80-90% by weight of vinyl acetate and the remainder is butyl acrylate, was added to the vessel. Stirring was continued for an additional 3-4 minutes at room temperature (about 25 ° C), after which, 17.6 g of ethylenediamine in 25 g of water was added to the vessel over a period of five minutes to extend the prepolymer chain to time that remains cold to the dispersion. The contents of the container were then dispersed for an additional 45 minutes.

EXAMPLE 5 Preparation of a polyurethane-acrylic-polysiloxane PIPN with subsequent crosslinking To a reaction vessel equipped with a nitrogen cover were charged 30.0 g of n-methyl pyrrolidone, 311.1 g of Rucoflex ™ 1015-120, 23 g of dimethylolpropionic acid, 3.6 g of trimethylolpropane, 5.0 g of 1,4-cyclohexane dimethanol and about 1.0 g of dibutyl tin dilaurate (10% solution in n-methyl) pyrrolidinone). The stirring then started and the temperature was increased to about 90 ° C. Then 45.5 g of IPDI and 155.1 g of m-TMXDI were added to the reaction vessel. The content of the container was then maintained from 3.5 to 4 hours, after which added 16.8 g of triethylamine at 85 ° C. The contents of the vessel were then maintained for an additional 15 to 20 minutes, followed by the addition of 13.0 g of primary soy amine (Kemamine P997D from Witco) and maintaining it for an additional 20 to 30 minutes. The prepolymer of The polyurethane was then transferred to a vessel containing 888.42 g of water and 16.8 g of triethylamine and dispersed for three minutes. To the vessel was then added an emulsion of polydimethylsiloxane having an amino functional group, which can be obtained in the form commercial Wacker Silicones as BS 1306, in an amount of 140.5 g and dispersed for three minutes. To the vessel was then added 3160,665 g of the acrylic latex of Example 1, which can be obtained in commercial form. Stirring was continued for an additional 3-4 minutes at room temperature (approximately 25 ° C), after which, 34.5 g of isophorone diamine in 55 g of water were added to the vessel over a period of five minutes to extend the prepolymer chain while keeping the dispersion cold. The contents of the vessel were then dispersed for an additional 45 minutes and subsequently filtered.

EXAMPLE 6 Preparation of polyurethane-acrylic-polysiloxane PIPN with subsequent crosslinking 30.0 g of n-methyl pyrrolidone, 311.13 g of the Rucoflex ™ 1015-120 polyester diol blend, 23.0 g of dimethylolpropionic acid, 3.0 g of trimethylolpropane, 5.0 g of 1,4-cyclohexane dimethanol and about 1.0 g of dibutyl tin dilaurate (10% solution in n-methyl pyrrolidinone) were charged into a reaction vessel equipped with a nitrogen blanket. Stirring started and the temperature was then increased to about 89 ° C. Then, 153.84 g of meta-1, 1,3,3-tetramethylxylylene diisocyanate (m-) were added to the vessel.

TMXDI) and 40.6 g of isophorone diisocyanate (IPDI) in a period of 20 minutes and the container was maintained for 3.5 to 4 hours. Triethylamine was added in an amount of 16.8 g at 85 ° C, the reaction was maintained for 5 minutes, followed by the addition of 2.18 g of aminopropyl triethoxy silane, after which the vessel was held for an additional 15 minutes. The resulting polyurethane prepolymer was then added to a vessel containing 848.8 g of water and dispersed for 3 minutes. The The polysiloxane emulsion BS 1306, which can be obtained commercially from Wacker, in an amount of 136.2 g was added and stirred for 2 minutes. The acrylic latex of Example 1, in an amount of 3064.2 g was then added to the container. Stirring was continued for 3 to 4 additional minutes at room temperature (approximately 25 ° C), after which 11.9 g of ethylene diamine in 22 g of water was added to the vessel over a period of 5 minutes to extend the prepolymer chain while keeping it cool to the dispersion. The content was then dispersed for an additional 45 minutes.

EXAMPLE 7 Preparation of a polyurethane-alkyd PIPN with subsequent cross-linking 25 A reaction vessel equipped with a The nitrogen blanket was charged with 50.0 g of n-methyl pyrrolidinone, 277.1 g of the Rucoflex ™ 1015-120 polyester diol blend, 26.2 g of dimethylolpropionic acid, 0.9 g of trimethylolpropane and about 1.0 g of dibutyl tin dilaurate ( 10% in n-methyl pyrrolidinone). The contents of the vessel were stirred and the temperature was increased to approximately 87 ° C. The addition then began in 20 minutes of 27.3 g of 4,4'-dicyclohexylmethane diisocyanate and 132.7 g of isophorone diisocyanate (IPDI). The content of the container was maintained for 3.25 hours, then 5.7 g of primary soy amine (Adogen 115D from Witco) was added. The reaction was maintained under these conditions for about 30 more minutes to create a polyurethane prepolymer. The resultant polyurethane prepolymer was then added to a vessel containing 667.8 g of water and 18.8 g of triethylamine and dispersed well. An alkyd emulsion, URADIL 516 acrylic, which can be obtained commercially from DSM Resins, in an amount of 3133.2 g (60% solids) was then added to the vessel. Stirring was continued for an additional 3-4 minutes at room temperature (approximately 25 ° C), after which 9.5 g of ethylenediamine in 20 g of water was added to the vessel over a period of five minutes to extend the prepolymer chain , while keeping dispersion cold. The content was then dispersed for an additional 45 minutes.

EXAMPLE 8A Preparation of Matte Exterior Painting Using standard paint manufacturing techniques, a matte exterior paint was prepared, using the polyurethane-acrylic PIPN of Examples 1 to 7. The formula of the paint was as follows: Percentage by weight PIPN 32 Water 10.2 Dispersant Tamol 165 -A 2.0 Surfactant Triton CF-10 0.4 Zinc oxide 2.2 Defoamer 0.09 Silica Minex 4 13.2 Clay 4.4 Talc 4.4 ag. of coalescence Dowanol DPNB 1.4 Fungicide 0.2 Pulp of Ti02 17.5 Water 11.4 Thickener Cellosize ER 0.4 Defoamer 0.3 EXAMPLE 8B Preparation of a glossy exterior paint Using standard paint manufacturing techniques, a glossy exterior paint was prepared, using the polyurethane-acrylic PIPN from examples 1 to 7. The formula of the painting was as follows: Percent by weight PIPN 54.2 Water 10 Dispersant Colloids 286N 0.4 Surfactant Surfynol CT111 0.2 Biocide 0.1 Deforamer Dehydran 1620 0.15 Ammonia 0.3 Associative thickener Acrylsol RM 2020 0.3 Associative thickener Acrylsol RM 825 0.4 Propylene glycol 0.5 Titanium dioxide 17.9 Water 0.8 DPNB 1.1 Dehydrating agent 1620 0.15 Thickener associative Acrylsol RM 825 0.4 Water 13 COMPARATIVE EXAMPLE 9 A bright paint was prepared using a cold mixture of: (i) 80% by weight of the acrylic latex of Example 3, which can be obtained commercially and (ii) 20% by weight of a polyurethane dispersion prepared substantially in accordance with the polyurethane prepolymer of Example 3, dispersed in water and subjected to chain extension with ethylene diamine. The latex and the polyurethane dispersion were used to prepare a glossy paint having the formula of the paint of Example 8B.

COMPARATIVE EXAMPLE 10 A matte paint was prepared using a cold mixture of: (i) 80% by weight of the acrylic latex of Example 3, which can be obtained in commercial form and (ii) 20% by weight of a polyurethane dispersion prepared practically from according to the polyurethane prepolymer of example 3, dispersed in water and subjected to chain extension with ethylenediamine. The latex and the polyurethane dispersion were used to prepare a matte paint having the formula of the paint of Example 8A.

COMPARATIVE EXAMPLE 11 A matte paint was prepared using a mixture 13L cold of: (i) 80% by weight of the acrylic latex of Example 3, which can be obtained in commercial form and (ii) 20% by weight of a polyurethane dispersion prepared substantially in accordance with the polyurethane prepolymer of Example 6, dispersed in water and subjected to chain extension with ethylenediamine and 7.5% by weight of the polysiloxane emulsion of example 6, which can be obtained in commercial form. To prepare a matte paint having the formula of the paint of Example 8A, the latex and the polyurethane dispersion were used with the polysiloxane mixture.

PERFORMANCE In the paints prepared with the partially interpenetrating networks of the present invention, its adhesion to powdered substrates was evaluated. Paints prepared using a standard latex polymer as well as paints prepared using cold mixtures of polyurethane and latex dispersions were also evaluated for comparison. Adhesion to powdery substrates was measured with the "peel strength" adhesion test. The substrates were highly dusty aluminum and latex panels, which had been weathered to the powder classification 2 of the ASTM. The preparation .-H of the test panel included the application of 2.5 grams of the test paint to a substrate area of 2 inches x 4 inches (5.08 cm x 15.4 cm); the immediate placement of a strip of sky blanket of 1.5 inches x 9 inches (3.81 cm x 22.85 cm) over the damp paint, leaving the edge protruding; 1.5 inches (3.81 cm); Firmly press the blanket of sky in the damp paints and then saturate the blanket of sky by applying an additional 5.5 grams of the test paint. After drying for 7 days under controlled conditions of 21 ° C and 50% relative humidity, a strip of 1 inch (2.54 cm) width was cut using a blade and a template along the sky blanket. The sample panel was then placed in a fog chamber for one hour. After removing the panel from the fog chamber, it was connected horizontally to a ring pedestal with a forward inclination of approximately 10 ° with respect to the perpendicular, using utilitarian jaws. The thin edge of the sample panel should be in the upward direction. A weight hanger was attached to the sky blanket by means of an S-hook or a paper clip. In the hanger the weight was then increased in increments of 10, 20 and 50 grams, until the sky blanket was peeled off or detached from the substrate at a rate of 10 to 20 mm / minutes. Unproved areas must be moist i? -li-i --- during the test by wrapping them with a piece of sky blanket saturated with water. The amount in grams of the weight required to achieve separation was reported, up to 2000 grams, as well as the mode of failure. Cohesive failure refers to the failure of the paint itself, rather than the failure of the bond between the test paint and the substrate. Adhesive failure refers to the separation of the test paint from the substrate. It is normally considered that reaching weights from 800 grams up in this test, is an important adhesion. In addition, any cohesive failure ("C" in Table 1), as opposed to a 100% adhesive failure ("A" in Table 1) is indicative of true adhesion improvements. Adherence to powdered substrates was also evaluated by the blister test of ASTM method D714. The test panels for this test were highly powdered aluminum substrates that had a powder classification of 2 of the ASTM, which were then coated with the glossy and matt latex paints, listed in Table 1. The test panels were dried for 1 day and then placed in a fog chamber for 15 to 22 hours. The panels were then tested according to the ASTM method D714, as shown in table 1.

J £ ji &!? * «Ie? --- á¡- ---- »-AirMM-iíW- ^ l - Bn-ftr-6 - SB-a- • - £ --B- WO-- * - • -». 13-- > , Ss -, --- * x *? * Á. ~ -.- »- S ya - ^ The wet adhesion of the paint prepared with the PIPNs of the present invention was evaluated when preparing panels of the same As those who prepared for the blister test, the panels were allowed to dry for 1 day, were placed in a fog chamber for 1 day and then the panels were allowed to recover during the day that followed the chamber. fog. The panels were then subjected to a chilling test in accordance with D3359 of the ASTM. The control latex paints listed in Table 1 were prepared practically in accordance with the glossy and matt paint formulas of Examples 8A and 8B. The latex polymer used consisted of 50% by weight butylacrylate, 48% by weight of methylmethacrylate and 2% weight of methacrylic acid. The results of the adhesion test are presented in Table 1. The paints prepared with the partially interpenetrating networks of the present invention have better adhesion, as measured by the D3359 method of the ASTM, than either latex by itself or cold mixtures of polyurethane and latex dispersions. The differences in performance are very noticeable in very dusty outdoor substrates. asü-a.-. . -aa-sasfe-. J- ^ ga ^^ - ^. J.a¿ --- < - »i ^ -i - ^.» -.- tJ ».. - > ---. . »* ** & . - «¿- ^ a-É ---». * ».-. ^ .. j &kjLix.

TABLE 1 Example ASTM ASTM Blister Adhesion Strength D3359 (1 D3359 (7 (1 day of wet for the days day of drying) (1 day of detached drying) drying drying) Brillant -e OB OB 6D 0B 650 A Control Mate control OB OB 6D 0B 650 A Example 1 in 4B 4B 10 5B > 2000 C matte paint Example 3 in 4B 4B 10 5B > 2000 C matte paint Example 3 in 3B 3B 10 4B > 2000 C brilliant paint: e Example 5 in 5B 5B 10 5B > 2000 C brilliant paint: e Example 6 in 5B 5B 10 5B > 2000 C matte paint Example 6 in 5B 5B 10 5B > 2000 C bright paint Example 9 6M Example 11 3B 3B 8M 1900 C / A - to-

Claims (17)

CLAIMS t 1. A process to produce a coating composition, the process comprises: a) preparing a polyurethane prepolymer having functional groups, the prepolymer has at least one functional group selected from hydroxy, isocyanate, acetoacetoxy and n-methylol; b) dispersing in water the polyurethane prepolymer having functional groups to form a
1. Dispersion of polyurethane prepolymer; c) adding to the polyurethane prepolymer dispersion a polymer component carried in water, wherein the polymer component carried in water does not contain functional groups that are amine, isocyanate, hydroxy or 15 carboxy reactants and d) extending the chain of the polyurethane prepolymer having functional groups with a chain extender, in the presence of the polymer component carried in water; Wherein the polymer component carried in water is selected from the group consisting of latex emulsions, acrylic polymers, water-reducible alkyds, alkyd emulsions, polyurethane emulsions, silicone emulsions, polyethylene emulsions, 25 dispersions of polyamide and mixtures thereof.
2. 2. The process according to claim 1, wherein the polyurethane prepolymer having functional groups comprises the reaction product of a composition containing active hydrogen and a composition 5 having the isocyanate functional group.
3. 3. The process according to claim 2, wherein the active hydrogen-containing composition is selected from the group consisting of diols, triols, amines, aminoalcohols, mercaptans and mixtures of the 10 same.
4. 4. The process according to claim 2, wherein the composition having the functional group comprises a diisocyanate. The process according to claim 4, wherein the diisocyanate is selected from the group consisting of aromatic, cycloaliphatic and aliphatic diisocyanates and mixtures thereof. 6. The process according to claim 5, wherein the diisocyanate is selected from the group consisting of 20 of 1, 6-hexamethylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-diphenylmethane diisocyanate, isophorone diisocyanate, cyclohexane- 1,4-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, p-xylylene diisocyanate, 25 meta-1, 1, 3, 3 -tetramethylxylylene diisocyanate and mixtures of the same. The process according to claim 1, wherein the polyurethane prepolymer contains functional groups that are crosslinked with film formation and 5 exposure to ambient conditions. The process according to claim 7, wherein the functional groups are selected from the group consisting of fatty amines, allylamines, diallylamines, ethoxylated allylamines, ethoxylated allyl alcohols, 10 fatty alcohols, allyl alcohols, trimethylol propane mono and diallyl ether, hydroxyethyl acrylate, hydroxyethyl methacrylate, mono and diglycerides obtained by alcoholysis of drying oils with polyols or the reaction of drying fatty acids with polyols, materials which 15 contain acetoacetate, drying oils having the anhydride functional group, trialkoxysilane and oils with epoxy functional group. 9. The process according to claim 1, wherein the polymer component carried in water comprises 20 a latex. The process according to claim 2, wherein the ratio of molar equivalents of NCO to the total active hydrogen equivalents is approximately between 1.01: 1 and 2.0: 1. 11. The process according to claim 2, in ^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^ where about 1% to about 10% by weight of total polymer solids is comprised by the active hydrogen containing compositions having at least one pendant or suspended ionizable group, the active hydrogen containing composition is select from the group consisting of diols, amines and mercaptans and the suspended ionizable group is selected from the group consisting of carboxylic acid, sulfonic acid, phosphoric acid, ammonium salts, phosphonium salts and sulfonium salts. The process according to claim 2, wherein the active hydrogen-containing composition is a diol selected from the group consisting of polyester diols, polyether diols, polyacetal diols, polyamide diols, polyamide diols, diols poly (alkylene ether), polythioether diols, polycarbonate diols, Bisphenol A and mixtures thereof. The process according to claim 1, wherein the chain extender is selected from the group consisting of polyols, aminoalcohols, primary or secondary amines aliphatic, alicyclic, aromatic and heterocyclic, silanes with amino functional group, silicones with amino functional group, polyisocyanates and polyaldehydes dispersible or emulsifiable in water. 14. A process for preparing a coating for surfaces having adhesion to powdery weathered surfaces, the process comprising: a) preparing a polyurethane prepolymer having the isocyanate functional group; 5 b) dispersing in water the polyurethane prepolymer having the isocyanate functional group to form a polyurethane prepolymer dispersion; c) adding to the polyurethane prepolymer dispersion having the isocyanate functional group a The polymer component carried in water, wherein the polymer component carried in water does not contain functional groups that are amine, isocyanate, hydroxy or carboxy reactive; and d) extending the polyurethane prepolymer chain having the isocyanate functional group with a chain extender, in the presence of the polymer component carried in water; wherein the polymer component carried in water is selected from the group consisting of emulsions of 20 latexes, acrylic polymers, water-reducible alkyds, alkyd emulsions, polyurethane emulsions, silicone emulsions, polyethylene emulsions, polyamide dispersions and mixtures thereof. 1
5. 5. The process according to claim 14, in 25 where the polyurethane prepolymer contains groups functional elements that crosslink with film formation and exposure to ambient conditions. The process according to claim 15, wherein the functional groups are selected from the group consisting of fatty amines, allylamines, diallylamines, ethoxylated allylamines, ethoxylated allyl alcohols, fatty alcohols, allyl alcohols, trimethylol propane mono and diallyl ether, hydroxyethyl acrylate , hydroxyethyl methacrylate, mono and diglycerides obtained by alcoholysis of drying oils with polyols or the reaction of drying fatty acids with polyols, acetoacetate-containing materials, drying oils having the anhydride functional group, trialkoxysilane and oils with epoxy functional group. The process according to claim 14, wherein the chain extender is selected from the group consisting of polyols, aminoalcohols, primary or secondary amines aliphatic, alicyclic, aromatic and heterocyclic, silanes with amino functional group and silicones with amino functional group.