One-pack ambient cure crosslinkable copolymer composition of vinyl branched ester and vinyl silane, and uses thereof

Abstract

The present invention relates to a method for producing a stable copolymer composition consisting of an organic solvent, an alkyl-alkoxysilane and / or a C1-C9 alcohol, where monomers and a radical initiator are added to a reactor. The copolymer composition is based on modified vinyl branched ester polymers with vinyl silanes and a water scavenger. The copolymer composition can be formulated to a desired viscosity that allows application by standard techniques, and the cure is optimized in the presence of an applied catalyst as a one-pack system cured at room temperature.

Description

[Technical Field]

[0001] The present invention relates to a method for producing stable resins for use in low temperature (below 80°C) moisture-curing one-package coatings, whereby silane copolymers are prepared by radical polymerization in the presence of non-polymerizable moisture scavengers such as alkoxysilanes, orthoesters or titanates and / or C1-C9 alcohols.

[0002] The coating composition comprises A) silane-vinyl ester copolymer, B) optionally pigments and fillers; C) solvent, D) paint additives, E) moisture scavengers such as alkoxysilanes, vinylsilanes, orthoesters, titanates, preferably vinylsilanes, most preferably vinyltrimethoxysilane; F) optionally a C1-C6 alcohol; G) optionally a polysiloxane polymer, and H) adhesion promoters, I) Curing catalyst It consists of:

[0003] The polymer compositions are particularly suitable for ambient cure (below 60°C) coating and adhesive applications. [Background technology]

[0004] The use of silanes in one-pack (1K) acrylic coating formulations is well known, particularly acrylic-silane coating compositions that have acceptable cure rates and, upon curing, produce films with good physical and chemical properties. However, one significant disadvantage of these compositions is their short pot life. For decades, the industry has been working on options to address this major drawback.

[0005] No. 4,043,953 relates to an ambient temperature, moisture-curable coating composition that achieves improved pot life by the present invention, which comprises a blend of an acrylic-silane interpolymer derived from a monomer lacking an active hydrogen atom, a cure-accelerating catalyst, and a monomeric hydrolytically reactive organosilicon compound represented by the structural formula: XnSi(OR)4-n.

[0006] EP0007765 makes the following comment regarding the above: "Although the method disclosed in US4,043,953 does improve the stability of polymeric organosilanes, we have found that this method has certain limitations, especially when it is desired to use the polymeric organosilanes as adhesion-promoting additives rather than as coatings themselves. When polymeric organosilanes are used as adhesion-promoting additives rather than as coating materials, the viscosity stability requirements are somewhat strict for several reasons. For this reason, EP0007765 and EP0050249 have found that the presence of low molecular weight alcohols and monomeric hydrolysis-reactive compounds has a synergistic effect on the stability of acrylic-silane interpolymers."

[0007] Twenty years later, WO0198419 still looks to physical separation of the catalyst, proposing a so-called one-pack system, where the catalyst is usually packaged separately from the (pigmented) polymer. The components are mixed together just before application of the coating. A quick-drying, storage-stable pseudo-one-pack system is possible using "double" cans, where the catalyst is stored separately from the paint in one can.

[0008] WO04067576 demonstrates that stable coating formulations can be obtained when the acrylic polymer is substantially free of functional groups that can react with polysiloxanes or catalysts. The document does not mention the properties of the coating. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] U.S. Patent No. 4,043,953 [Patent Document 2] European Patent No. 0007765 [Patent Document 3] European Patent No. 0050249 [Patent Document 4] International Publication No. 2001 / 98419 [Patent Document 5] International Publication No. 2004 / 067576 Summary of the Invention [Problem to be solved by the invention]

[0010] Therefore, there is a need for compositions and methods of applying such compositions that have reduced cure cycles and cure temperatures while minimizing the effects of undesirable chemicals. Most preferably, the industry is looking for a system that can be cured at room temperature after application, yet is stable in the can before application. [Means for solving the problem]

[0011] (Summary of the Invention) SUMMARY OF THE INVENTION Embodiments of the present invention are directed to methods that result in polymer compositions and methods for applying polymer compositions that exhibit improved stability.

[0012] In one aspect of the present invention, there is provided a method for producing a polymer composition, the composition comprising an organosilane copolymer derived from at least A1 and A2 monomers, wherein the A1 monomer comprises a vinyl ester monomer and the A2 monomer comprises a vinyl silane monomer, and a non-polymerizable moisture scavenger (E) selected from the group consisting of alkoxysilanes, orthoesters, titanates, zirconates, oxazolidines, sulfates, and / or C1 to C9 alcohols, and combinations thereof.

[0013] Another aspect of the present invention provides a method for applying a composition, the composition comprising an organosilane copolymer derived from at least A1 and A2 monomers, where the A1 monomer comprises a vinyl ester monomer and the A2 monomer comprises a vinyl silane monomer, and a moisture scavenger selected from the group consisting of vinyl silanes, orthoesters, titanates, zirconates, oxazolidines, sulfates, and / or C1-C9 alcohols, and combinations thereof. The composition may further comprise one or more materials selected from the group consisting of solvents, catalysts, pigments, fillers, coating additives, C1-C6 alcohols, polysiloxane polymers, adhesion promoters, and combinations thereof. The composition may be further cured in the presence of moisture. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention provides a method for producing a polymer composition exhibiting improved stability and a method for applying the polymer composition. The method comprises reacting a vinyl ester monomer, a silane-functional monomer, and an organic peroxide in the presence of a non-polymerizable moisture scavenger selected from the group consisting of an alkoxysilane, an orthoester, or a titanate, preferably an alkyl-alkoxysilane, and / or a C1-C9 alcohol at a reaction temperature of 80°C to 200°C. Preferred alkyl-alkoxysilanes are methyltrimethoxysilane, ethyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, or blends thereof, and / or C1-C9 alcohols, such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, terbutanol, pentanol, hexanol, heptanol, octanol, isononanol, and combinations thereof. It has been found that the combination of an alkyl-alkoxysilane and an alcohol has a synergistic effect on the stability of the formulation.

[0015] Here, the alkyl-alkoxysilane and the C1-C9 alcohol are present in a weight ratio of 100 / 0 to 30 / 70.

[0016] Here, the moisture scavenger is present in a weight ratio of 1 / 100 to 15 / 85 based on the total amount of the monomers used.

[0017] The polymer composition must include an organosilane copolymer and a moisture scavenger. The moisture scavenger may be selected from the group consisting of vinyl silanes, alkyl silanes, orthoesters, titanates, zirconates, oxazolidines, sulfates, and / or C1-C9 alcohols, and combinations thereof. The polymer composition is useful in coatings and other applications. The composition may further include one or more materials selected from the group consisting of solvents, catalysts, pigments, fillers, paint additives, C1-C6 alcohols, polysiloxane polymers, adhesion promoters, and combinations thereof.

[0018] The polymer compositions can be formulated to a desired viscosity that allows application by standard coating techniques, and the cure rate is optimized in the presence of an applied catalyst.

[0019] The polymer composition can include an organosilane copolymer and a moisture scavenger. The organosilane copolymer can comprise 10% to 60% by weight of the polymer composition, e.g., 5% to 80% by weight, such as 20% to 50% by weight. The moisture scavenger can comprise 0.1% to 5% by weight of the polymer composition, e.g., 0.05% to 10% by weight, such as 1% to 3% by weight.

[0020] The polymer composition includes an organosilane copolymer. In one embodiment, the organosilane copolymer is derived from at least A1 and A2 monomers, where the A1 monomer includes a vinyl ester monomer and the A2 monomer includes a silane-functional monomer such as vinylsilane trimethoxy, vinyltriethoxysilane, methylvinyldiethoxysilane, an acrylosilane monomer, a methacrylosilane monomer, or a combination thereof. The copolymer may also be derived from one or more optional monomers selected from the group consisting of a monomer including vinyl acetate (A3 monomer), a monomer including an acrylic acid ester, a monomer including a methacrylic acid ester (A4 monomer), or a combination thereof, a monomer including any other vinyl monomer other than a vinyl ester or vinylsilane (A5 monomer), and a combination thereof.

[0021] The A1 monomers, including vinyl ester monomers, have the formula:

[0022] [ka] [In the formula, R1, R2, and R3 are hydrogen or an alkyl group having 1 to 15 carbon atoms, and the total number of carbon atoms in R1, R2, and R3 is in the range of 1 to 20.] In one embodiment, the total number of carbon atoms in R1, R2, and R3 ranges from 5 to 12. Suitable vinyl esters include those derived from branched acids, such as pivalic acid, 2-ethylhexanoic acid, and neo-acids (also known as VERSATIC Acids™ from Hexion Inc.) where the total carbon atoms in R1, R2, and R3 are 7, 8, 9, and 10. Examples of these vinyl ester monomers include vinyl pivalate, vinyl 2-ethylhexanoate, vinyl neodecanoate, and vinyl neononanoate, and combinations thereof. Commercially available examples of vinyl ester monomers include VeoVa9, VeoVa10, and combinations thereof, available from Hexion Inc., Columbus, Ohio.

[0023] The vinyl ester monomer, A1 monomer, can comprise 15% to 95% by weight, such as 30% to 95% by weight, 50% to 90% by weight, etc., of the total weight percent of monomers (100% by weight).

[0024] The vinyl silane monomer, A2 monomer, has the formula:

[0025] [ka] or

[0026] [ka] [In the formula, R4, R5, and R6 are alkyl groups having 1 to 4 carbon atoms.] Suitable vinyl silanes and R4-R6 are methoxy or ethoxy. Suitable examples of these vinyl silane monomers include vinyl silane trimethoxy, vinyl triethoxy silane, methyl vinyl diethoxy silane, and combinations thereof. Commercially available examples of vinyl silane monomers include Silquest A171 and Silquest A151, and combinations thereof, available from Momentive Performance Materials Inc., New York, USA (or country or city and state for the United States).

[0027] Monomer A2 containing acrylosilane or methacrylosilane can also be used in the copolymer. Suitable examples of acrylosilane monomers include methacryloxypropylmethyldimethoxysilane, methacryloxytrimethoxysilane, and methacryloxytriethoxysilane, and combinations thereof. Commercially available examples of acrylosilane monomers include Silquest A174, Silquest * Y-11878 and combinations thereof, which are commercially available from Momentive Performance Materials Inc. (company name) of New York, USA (or country or city and state in the case of the United States).

[0028] The vinylsilane monomer, A2 monomer, can comprise 2% to 25% by weight, such as 2% to 20% by weight, or 1% to 35% by weight of the total weight percent (100% by weight) of the monomers. The acrylosilane-containing monomer, A2 monomer, A2 monomer can comprise 0% to 15% by weight, such as 5% to 10% by weight, or 0% to 25% by weight of the total weight percent (100% by weight) of the monomers.

[0029] The vinyl acetate-containing monomer, A3 monomer, can comprise 0% to 75% by weight of the total weight percent of the monomers (100% by weight), such as 0% to 60%, 20% to 50%, etc.

[0030] Monomers containing acrylic acid esters, methacrylic acid esters, or combinations thereof, A4 monomers, can also be used in the copolymer. Suitable examples of A4 monomers include methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, isopropyl methacrylate, isobornyl methacrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate, and combinations thereof. The monomers containing acrylic acid esters, methacrylic acid esters, or combinations thereof, A4 monomers, can comprise 0% to 40%, 5% to 25%, or 0% to 97% by weight of the total weight percent (100% by weight) of the monomers.

[0031] Monomers, A5 monomers, including any vinyl monomer other than vinyl esters or vinyl silanes, can also be used in the copolymer. Suitable examples of A5 monomers include N-vinylpyrrolidone, vinyl ethers, acrylic acid, methacrylic acid, and combinations thereof.

[0032] Monomers, A5 monomers, including any vinyl monomer other than vinyl esters or vinyl silanes, can comprise 0% to 30% by weight, such as 0% to 10% by weight, 0% to 5% by weight, etc., of the total weight percent of monomers (100% by weight).

[0033] In one embodiment of the present invention, the copolymer derived from at least A1 and A2 monomers comprises 10% to 95% by weight of A1 monomer; 5% to 35% by weight of A2 monomer; 0% to 75% by weight of A3 monomer; 0% to 97% by weight of A4 monomer, and 0% to 30% by weight of A5 monomer (wherein the weight percents are based on the total weight of at least A1 and A2 monomers, and the total weight percent is 100 weight percent).

[0034] The copolymer may have a number average molecular weight of from 1,000 Daltons to 40,000 Daltons, such as from 2,000 Daltons to 25,000 Daltons, from 3,500 Daltons to 12,000 Daltons.

[0035] Suitable moisture scavengers for the coating composition may be selected from the group consisting of vinyl silanes, orthoesters, titanates, zirconates, oxazolidines, calcium sulfate, calcium oxide, isocyanates, zeolite-based molecular sieves, and combinations thereof. Examples of moisture scavengers include vinyltrimethoxysilane, vinyltriethoxysilane, trimethyl orthoformate, triethyl orthoformate, triethyl orthoacetate, tetra-n-butyl titanate, di-isobutoxyl titanium chelate with ethyl acetoacetate, and combinations thereof.

[0036] In one embodiment, the polymer composition comprises a coating formulation including a copolymer based on the monomers described herein, a moisture scavenger described herein, a catalyst, an organic solvent, and optionally one or more additives.

[0037] In one embodiment, the copolymer may comprise 10% to 90% by weight, such as 5% to 80% by weight, 10% to 60% by weight, of the total weight percent (100% by weight) of the coating formulation.

[0038] In one embodiment, the moisture scavenger may comprise 0.05% to 15% by weight, such as 0.1% to 10% by weight, 0.2% to 5% by weight, of the total weight percent (100% by weight) of the coating formulation.

[0039] The catalyst may be selected from the group consisting of strong acids, Lewis acids, carboxylic acids, amines, bases such as caustic alkalis or alcoholates, and combinations thereof. Alternative catalysts are nitrates of polyvalent metal ions, such as calcium nitrate, magnesium nitrate, aluminum nitrate, zinc nitrate, or strontium nitrate. Nitrates can also be advantageously combined with amines. Other catalysts include carbonates, such as sodium carbonate or calcium carbonate. Commercially available examples of catalysts include SiliXan Cat 240 (SiliXan GmbH), Nacure 4054, Nacure 5076, TYZOR TNBT, TYZOR 9000, K-Kat 670 (King Industries), DBTDL (dibutyltin dilaurate) (Sigma Aldrich), 3-aminopropyltrimethoxysilane (Sigma), 2-ethylhexanoic acid, Versatic acid (Hexion), and combinations thereof. A preferred commercially available catalyst for one-package systems for coating formulations is DBTDL.

[0040] In one embodiment, the catalyst may comprise 0.1 wt % to 3 wt %, such as 0.2 wt % to 2 wt %, 0.3 wt % to 1 wt %, of the total weight percent (100 wt %) of the polymer composition.

[0041] The organic solvent may be selected from the group consisting of esters, ethers, ketones, aromatic and aliphatic compounds, and combinations thereof. Examples of organic solvents include butyl acetate, xylene, methyl amyl ketone, ethoxyethyl propionate, and combinations thereof.

[0042] In one embodiment, the organic solvent may comprise 5% to 60% by weight, such as 10% to 55%, 25% to 50%, etc., of the total weight percent (100% by weight) of the polymer composition.

[0043] The optional one or more additives can include one or more materials including pigments, fillers, paint additives, C1-C6 alcohols, polysiloxane polymers [[of the formula xO-Si(R,R')ny]], adhesion promoters, and combinations thereof.

[0044] The C1-C6 alcohol may be selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, and combinations thereof. The formulation may have 0 wt% of the optional C1-C6 alcohol. When present, the C1-C6 alcohol may be 0.1 wt% to 15 wt%, such as 1 wt% to 10 wt%, 2 wt% to 6 wt%, etc., of the total weight percent (100 wt%) of the polymer composition.

[0045] Suitable polysiloxane polymers may be selected from the group consisting of linear and branched polyalkylsiloxanes and combinations thereof. The formulation may have 0 wt% polysiloxane polymer. When present, the polysiloxane polymer may be 1 wt% to 60 wt%, such as 5 wt% to 30 wt%, 10 wt% to 25 wt%, etc., of the total weight percent (100 wt%) of the polymer composition.

[0046] Adhesion promoters may include epoxy silanes, alkoxy silanes and amino silanes, titanates and zirconates, and combinations thereof. Examples of suitable adhesion promoters may be selected from the group consisting of epoxypropyltrimethoxysilane and epoxy silane oligomers, and combinations thereof. Commercially available examples of adhesion promoters include Silquest A-187, Silquest A-1871, and CoatOsil MP200, available from Momentive Performance Materials, Inc., New York, USA.

[0047] The formulation may have 0 wt. % adhesion promoter. When present, the adhesion promoter may be 0.05 wt. % to 4 wt. % of the total weight percent (100 wt. %) of the polymer composition.

[0048] Pigments can include anatase and rutile titanium dioxide, lead oxide, zinc oxide, iron oxide, carbon black, and organic pigments, as well as combinations thereof. Examples of suitable pigments can be selected from the group consisting of titanium oxide, iron oxide, and combinations thereof. The formulation can have 0% by weight of pigment. When present, the pigment can be 5% to 50% by weight, e.g., 5% to 40% by weight, or 3% to 60% by weight, of the total weight percent (100% by weight) of the polymer composition. Preferred pigments are those with low moisture content (less than 2%). Titanium dioxide can have a hydrophobic surface treatment, particularly a hydrophobic treatment. Preferred titanium dioxide grades have a hydrophobic surface treatment, such as silicone. These include Ti-Pure™ R-350 from Chemours and 2222 from Kronos GmbH.

[0049] Fillers can include barium and calcium sulfates, silica oxides, silicates, and combinations thereof. The formulation can have 0 wt. % fillers. When present, the fillers can be 5 wt. % to 50 wt. %, such as 10 wt. % to 40 wt. %, 10 wt. % to 30 wt. %, etc., of the total weight percent (100 wt. %) of the polymer composition.

[0050] Paint additives can include UV stabilizers, corrosion inhibitors, heat stabilizers, slip and mar additives, biocides, thickeners, and combinations thereof. The formulation can have 0 wt. % of the paint additives. When present, the paint additives can be 0.01 wt. % to 8 wt. %, such as 0.02 wt. % to 6 wt. %, 0.02 wt. % to 5 wt. %, of the total weight percent (100 wt. %) of the polymer composition.

[0051] In one embodiment, the formulation comprises: 5% to 80% by weight of an organosilane copolymer; 0.1% to 10% by weight of a moisture scavenger; 5% to 60% by weight of a solvent; 0.05 wt.% to 3.0 wt.% of a catalyst; 0% to 15% by weight of a C1 to C6 alcohol; 0% to 60% by weight of a polysiloxane polymer; about 0% to about 4% by weight of an adhesion promoter, and 0% to 60% by weight of paint additives / pigments / fillers (wherein the weight percents are based on the total weight of said composition, with the total weight percent being 100 weight percent).

[0052] The total weight percent of the components of the polymer composition comprises 100 weight percent.

[0053] The present invention also relates to a one-package system comprising a copolymer based on the monomers described herein, a moisture scavenger as described herein, a catalyst, an organic solvent, and optionally one or more additives, and having an extended shelf life of at least one month. The one-package system has the weight percentages of ingredients as described for the formulations described herein.

[0054] In order to provide a better understanding of the present invention, including representative advantages thereof, the following examples are presented. [Example]

[0055] The following procedures and examples are set forth to enable those skilled in the art to more fully understand the invention set forth herein. Unless otherwise specified, the following units of measurement and definitions apply in this application: all parts and percentages are by weight; temperatures are in degrees Celsius (°C).

[0056] experiment For the examples below, the data was derived according to the following procedure.

[0057] Solids: Solids is the weight percent of non-volatile material present in a coating formulation. Solids is measured by weight loss in a ventilated oven at 110°C for 1 hour.

[0058] Viscosity: Viscosity is the resistance of a polymer formulation to flow. Viscosity is determined by a Brookfield viscometer.

[0059] Molecular weight: Molecular weights are given as weight and number average Mw determined by gel permeation chromatography using polystyrene as standard, tetrahydrofuran as elution solvent and refractive index as detector, as described in DIN standard 55672.

[0060] Pot Life: Pot life is an estimate of the time a polymer composition can be used in a particular application. Pot life is usually determined by the time it takes for a formulated system to double its initial viscosity in a closed can after application has been performed.

[0061] Shelf life: Shelf life is an estimate of the time a formulated binder can be stored under typical storage conditions without losing its performance. Shelf life is usually determined by measuring viscosity change.

[0062] Stability: The stability of a 1K moisture-curing system is comparatively studied by checking the maximum % amount of water that can be added to the binder before it gels in a closed pot.

[0063] The following examples were carried out and are provided to illustrate the present invention and should not be construed as limiting the scope of the invention.

[0064] Examples 1-8: In a glass reactor equipped with a stirrer and nitrogen inflow. The initial reactor charge is injected into the reactor and a nitrogen blanket is applied (10 ln / h). The stirrer is set to 80 RPM. The temperature is set to 115°C. A monomer mixture is prepared by mixing the monomers and initiator. Once the temperature in the reactor is reached, a shot of initiator is added and the nitrogen flow is stopped. The monomer mixture is then added to the reactor over 4 hours. At the end of the addition, a booster consisting of initiator and solvent is added at 115°C for 1 hour. The reactor is then held at the same temperature for another hour. Finally, the reactor is cooled to below 80°C and the product is discharged.

[0065] [Table 1]

[0066] The best stability results (lowest PDI, highest maximum water content before gelation) are obtained by using butanol (Example 4) in the initial reactor charge, MTMS (Example 5), or a combination of butanol and MTMS (Example 8).

[0067] Enhanced Stability: Post-added (see recipe - no acrylates) Examples 8 to 18: Example 1 is mixed with different stabilizers and stability is evaluated by adding ppm of water to the system until it gels.

[0068] [Table 2]

[0069] The best stability results (highest maximum water content before gelation) are obtained by using vinyltrimethoxysilane (Example 12) as the moisture scavenger or by using a combination of alcohol and vinyltrimethoxysilane (Example 18).

[0070] Enhanced Stability: Synthetic (Replace VV9 with high Tg acrylate) Examples 19-26: In a glass reactor equipped with a stirrer and nitrogen inflow. The initial reactor charge is injected into the reactor and a nitrogen blanket is applied (10 ln / h). The stirrer is set at 80 RPM. The temperature is set to 115°C for Examples 19-20 and 105°C for Examples 21-26. A monomer mixture is prepared by mixing the monomer and initiator. Once the temperature in the reactor is reached, a shot of initiator is added and the nitrogen flow is stopped. The monomer mixture is then added to the reactor over a period of 4 hours. At the end of the addition, a booster consisting of initiator and solvent is added for 1 hour at 115°C for Examples 19-20 and 105°C for Examples 21-26. The reactor is then held at the same temperature for an additional hour. Finally, the reactor is cooled to below 80°C and the product is discharged.

[0071] Examples 22-24 demonstrate a stable process and stable product upon discharge when VeoVa9 is replaced with a high Tg acrylate. Example 25 gelled during processing, while Example 26 was successfully stabilized by increasing the alcohol level in the initial reactor charge.

[0072] Coating formulation procedure: The resin is first diluted with a (synthetic) solvent to a viscosity of 100-200 cP. The catalyst DBTDA is then added to the diluted resin at a 0.5% active level. The formulated resin is then applied 100 μm wet onto the panel using a Mayer rod and allowed to dry at 23±2°C and 50±5% relative humidity.

[0073] [Table 3]

[0074] [Table 4]

[0075] The as-applied properties show similar drying development for the VeoVa9-based and high Tg acrylate-based materials.

[0076] High Gloss Formulation: Synthesis in the Presence of Styrene

[0077] [Table 5]

[0078] Combining a portion of the styrene with VeoVa10 in the initial reactor charge provides the best synthesis results at discharge (Examples 38-39).

[0079] Examples 36-39 are applied by first diluting the system with a synthesis solvent to a viscosity of 100-200 cP. The catalyst, DBTDA, is then added to the diluted resin at a 0.5% active level. The formulated resin is then applied 100 μm wet onto a panel using a Mayer rod and allowed to dry at 23±2°C and 50±5% relative humidity.

[0080] [Table 6]

[0081] Example 38, which contains the highest level of styrene, gives the best gloss.

[0082] Additional examples with VAM (including better translation) Examples 46 and 48 were compared by GPC before the boost step. Example 46 showed about 11% area of ​​unconverted monomer before the boost step, while Example 48 showed 4%. Without the addition of a booster, Example 48 could achieve complete conversion if applied for an additional hour.

[0083] Samples 51, 52 and 53 were formulated as in Examples 36-39.

[0084] [Table 7]

[0085] [Table 8]

[0086] Example 54: In a glass reactor equipped with a stirrer and nitrogen inflow. The initial reactor charge is injected into the reactor and a nitrogen blanket is applied (10 ln / h). The stirrer is set at 80 RPM. The temperature is set at 115°C. A monomer mixture is prepared by mixing the monomers and initiator. Once the temperature in the reactor is reached, a shot of initiator is added and the nitrogen flow is stopped. The monomer mixture is then added to the reactor over a period of 4 hours. At the end of the addition, a booster consisting of initiator and solvent is added at 115°C for 1 hour. The reactor is then held at the same temperature for an additional hour. Finally, the reactor is cooled to below 80°C and the product is discharged.

[0087] [Table 9]

[0088] [Table 10]

[0089] Coating formulation procedure: First, the resin is diluted with a solvent (butyl acetate) to a viscosity of 300 cP. The catalyst DBTDL is then added to the diluted resin at a 1% active level. In Examples 55 and 56, the additive is added at a 3% active level. The formulated resin is then applied 150 μm wet onto a stainless steel panel using a Mayer rod and allowed to dry at 23±2° C. and 50±5% relative humidity.

[0090] Adhesion test on stainless steel: After 7 days of drying, adhesion evaluation is carried out by tape test according to ASTM D3359.

[0091] [Table 11]

[0092] The best adhesion results on stainless steel panels are obtained when an additive is added to the resin.

[0093] Adhesion test on epoxy primer: A fast-drying, high-solids epoxy primer paint recommended for permanent barrier protection in coating systems for severe corrosive environments is applied wet to a stainless steel panel at 150 μm using a Meyer rod and allowed to dry for 21 days at 23 ± 2°C and 50 ± 5% relative humidity.

[0094] The resin is diluted with a solvent (butyl acetate) to a viscosity of 300 cP. The catalyst DBTDL is then added to the diluted resin at an active level of 1%. In Example 2, the additive is added at a 3% active level. The formulated resin is then coated onto an epoxy primer paint at 150 μm wet using a Mayer rod and allowed to dry for 7 days at 23±2°C and 50±5% relative humidity.

[0095] [Table 12]

[0096] By adding 3% active gamma-aminopropyltrimethoxysilane to the resin, improved adhesion is observed on epoxy primers.

[0097] Paint adhesion test on epoxy primer: Pigmented Topcoat Formulation with Resin of Example 54:

[0098] [Table 13]

[0099] Add items 1 through 5 to an appropriately sized stainless steel mixing vessel. Begin low-speed stirring with a Coles-type dispersing blade to homogenize the material. While gently stirring, slowly begin adding item 6. As the viscosity increases, increase the disperser speed. Once all the pigment has been added to the vessel, increase the speed until a toroidal flow or donut effect is achieved. After a few minutes, stop stirring and scrape the vessel walls with a spatula, then resume the dispersion process. After 20 minutes, stop the stirrer and check the grind using a Hegman gauge. It should be above 7. If not, continue grinding for another 20 minutes. Once the grind is achieved, add the remaining ingredients (items 7 and 8). Then gradually add the solvent (items 9 and 10), reducing the stirring speed if necessary to avoid splashing. Filter through a 375 μm mesh and place in a metal can. Add additional solvent if necessary to reach a viscosity of 70 KU.

[0100] The catalyst DBTDL is added to the diluted paint at a 1% active level based on polymer solids. For Examples 55-61, the additive is added at the levels listed in the table. The formulated paint is then applied 150 μm wet onto the epoxy primer paint using a Mayer rod and allowed to dry for 7 days at 23±2°C and 50±5% relative humidity.

[0101] [Table 14]

[0102] By adding one of the listed additives, improved adhesion is observed on epoxy primers.

[0103] Improving paint gloss and stability: Use of new dispersants.

[0104] [Table 15]

[0105] The paint is prepared according to the procedure described above. The catalyst DBTDL is added to the diluted paint at a 1% active level. The formulated paint is then applied wet to a stainless steel panel at 150 μm using a Mayer rod and left to dry for 7 days at 23±2°C and 50±5% relative humidity.

[0106] Example 63, which contains Disperplast P as the dispersant, gives the best paint gloss.

[0107] The graffiti resistance of the coating of Example 63 is evaluated using manual solvent rub according to ASTM D6578.

[0108] Graffiti marking materials used: 1. Solvent ink marker, blue 2. Solvent-based spray paint, red 3. Wax crayon, black Cleaning materials evaluated: 1. Dry 100% propylene white base sheet 2. Citrus-based cleaner 3. Isopropyl alcohol 4. Methyl ethyl ketone The solvent-based ink marker blue applied on the paint from Example 63 comes off after 5 cycles of cleaning material 1, 25 cycles of cleaning material 2, and 3 cycles of cleaning material 3.

[0109] The solvent-based spray paint red is removed after 25 cycles of cleaning materials 1, 2, 3 and 2 cycles of cleaning material 4.

[0110] The black wax crayon is removed after 12 cycles of cleaning material 1.

Claims

1. 1. A method for producing a stable copolymer composition, comprising the step of radically copolymerizing a monomer mixture A in the presence of 0.5 to 10 weight percent of a non-polymerizable moisture scavenger, 0.5 to 15 weight percent of a C1 to C9 alcohol, and 0 to 40 weight percent of another solvent or additive, wherein said monomer mixture A comprises, based on the total weight percent of the monomers in said monomer mixture A: ・A １ 10 to 95% by weight of a vinyl ester monomer of the formula: 【Chemistry 1】 wherein R1, R2, and R3 are hydrogen or alkyl groups having 1 to 15 carbon atoms, and the total number of carbon atoms in R1, R2, and R3 ranges from 7 to 10 carbon atoms; and ・A ２ 3 to 35 weight percent of a silane-functional monomer of the formula: 【Chemistry 2】 [wherein R4, R5, and R6 are alkyl or alkyloxy groups having 1 to 4 carbon atoms.] ・A ３ 60 to 0% by weight of vinyl acetate, ・A ４ 97 to 0% by weight of an acrylate or methacrylate monomer, and ・A ５ 0 to 30% by weight of other copolymerizable vinyl monomers A method comprising:

2. The method of claim 1 , wherein the non-polymeric moisture scavenger is an alkoxysilane, an orthoester, or a combination thereof.

3. 3. The method of claim 2, wherein the alkoxysilane is methyltrimethoxysilane, ethyltrimethoxysilane, methyltriethoxysilane, or ethyltriethoxysilane, and the orthoester is an orthoformate or an orthoacetate.

4. 2. The method of claim 1, wherein the C1 to C9 alcohol is propanol, isopropanol, butanol, isobutanol, terbutanol, pentanol, hexanol, heptanol, octanol, isononanol, or a combination thereof.

5. 5. The method of claim 4, wherein the C1 to C9 alcohol is butanol.

6. The monomer mixture A is 15% by weight to 95% by weight of A １ Monomer and 5% to 35% by weight of A ２ and a monomer.

7. The monomer mixture A is 10% by weight to 95% by weight of A １ monomer, 5% by weight to 35% by weight of A ２ monomer, 0% to 60% by weight of A ３ monomer, 0% to 97% by weight of A ４ monomer, 0% to 30% by weight of A ５ monomer The method of claim 1 , comprising:

8. A stable copolymer composition prepared by the method of any one of claims 1 to 7.

9. 10. A formulation comprising the stable copolymer composition of claim 8 and one or more materials selected from the group consisting of solvents, catalysts, pigments, fillers, paint additives, C1-C6 alcohols, polysiloxane polymers, adhesion promoters, and combinations thereof.

10. 5% to 80% by weight of the stable copolymer composition; 0.1% to 10% by weight of said moisture scavenger; 5% to 60% by weight of a solvent; 0.05 wt.% to 3.0 wt.% of said catalyst; 0% to 15% by weight of said C1 to C6 alcohol; 0% to 60% by weight of said polysiloxane polymer; 0% to 4% by weight of said adhesion promoter, and 0% to 60% by weight of paint additives, pigments, fillers, or combinations thereof 10. The formulation of claim 9, comprising:

11. 10. The formulation of claim 9 which is a one-pack ambient temperature cure coating formulation.

12. 10. An object coated with the formulation of claim 9.

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