A two-component composition, process for its preparation and use

Abstract

The present application relates to a kind of two-component composition and its preparation method and application, belong to wood sealing primer technical field.The two-component composition described in the present application, include component A and component B;Wherein: the component A includes epoxy resin a1 and epoxy silane;In the component A, the weight of the epoxy silane accounts for 18-80wt% of the total weight of the epoxy resin a1 and the epoxy silane;The component B includes adduct and aminosilane;In the component B, the weight of the adduct accounts for 10-80wt% of the total weight of the adduct and the aminosilane.The two-component composition of the present application is low in odor, hardness is established and early polishing is established very fast, pot life is extremely excellent, simultaneously with excellent surface effect, flexibility, does not contain organic solvent or only has low content of organic solvent, can be widely applied as composition in wood sealing primer, to improve the performance of wood coating.

Description

Technical Field

[0001] This invention relates to the field of wood sealing primer technology, and in particular to a two-component composition, its preparation method, and its application. Background Technology

[0002] Against the backdrop of increasingly stringent carbon emissions and emission controls, the environmental attributes of coating products have become one of the core indicators for industry entry and market competition. VOCs in coating systems are largely contributed by diluents and organic solvents, which continuously escape during curing, drying, and film formation, not only increasing atmospheric emission pressure but also raising health risks for workers. Compared to solvent-free / ultra-low VOC coatings, traditional solvent-based coatings, due to their high solvent content and emission intensity, are struggling to meet increasingly stringent regulations and customer requirements. Therefore, the research and application of low-VOC or even near-zero VOC wood coating systems has become an inevitable trend.

[0003] In the wood coating process chain, the first primer (i.e. wood sealing primer) plays a key role in "wetting-penetration-sealing-bridging", which directly determines the adhesion, smoothness and final appearance stability of subsequent coatings. However, wood is a porous and hygroscopic substrate, and the core shortcomings of traditional solvent-based wood sealing primers lie in the systemic problems caused by "high solvent dependence": First, the VOC emission intensity is high, and the amount of volatilization during the drying process is high, resulting in obvious odor, environmental compliance pressure, and personnel exposure risks; Second, the solvent has a stronger wetting and swelling effect on the wood, which can easily induce substrate deformation such as fiber bulging and rib swelling. Moreover, under the migration and carrying effect of the solvent, the wood contents are more likely to seep into the coating film, causing defects such as yellowing, discoloration, and mottled appearance; Third, in order to achieve workability, further dilution is often required, which leads to a decrease in solid content and a limited film thickness in one application. Multiple applications are required to achieve coverage and fullness, resulting in a disadvantage in overall construction efficiency and material utilization; Fourth, solvent vapors are flammable, and the safety risks in storage, paint mixing, spraying, and drying are higher. There is a strong dependence on explosion-proof ventilation, recycling and treatment, and fire protection systems, which increases the overall management cost.

[0004] Solvent-free coating systems typically achieve the required application viscosity and film formation through high-solids resins, reactive diluents, or water-based / radiation curing technologies. This significantly reduces VOC sources, resulting in lower on-site odor and harmful volatile emissions, making it easier to meet environmental regulations and indoor air quality control requirements. Simultaneously, due to the reduced volatile components, the volume shrinkage of the coating film during curing is more controllable, porosity is lower, and sealing and chemical resistance are often superior. This helps suppress yellowing, staining, and other appearance problems caused by the migration of wood extracts (tannins, oils, etc.). The swelling effect on wood fibers is also relatively weakened, reducing the probability of substrate defects such as fuzzing and roughening, thereby improving the sandability of the primer, interlayer adhesion, and the consistency and durability of the overall coating. Furthermore, solvent-free systems generally have higher flash points and less flammable vapor, simultaneously reducing the risk of fire and explosion during production and construction, as well as the pressure of solvent storage and transportation management, making occupational health and safety management more controllable.

[0005] Currently, there are two main approaches to the development of solvent-free / ultra-low VOC wood primers:

[0006] One type is water-based one- or two-component sealing primers based on acrylic emulsions / resins / dispersions, with related solutions disclosed in patents such as CN104761992B, CN105295607B, CN105602377B, and CN109111835B. However, these water-based acrylic sealing primers generally have a low degree of crosslinking, slow drying and curing, and weaker film density and sealing properties compared to solvent-based systems. In addition, due to the high Tg of acrylic resins, a certain amount of film-forming aids often needs to be added to the formulation. Although VOCs have been significantly reduced, there is still room for further reduction.

[0007] Secondly, there are solvent-free two-component sealing primers developed around epoxy resins and amine curing agents. Patent CN120271791A discloses a two-component composition comprising component A and component B. Component B contains a small-molecule aminosilane (1c) with a strong odor, which is highly irritating to the human respiratory tract and has a lachrymatory effect. The substituted phenol (1d) also has a strong amine odor. The odor does not meet customer requirements, and early sanding performance is poor, requiring overnight sanding, indicating significant room for improvement. Patent CN121182303A discloses a low-odor two-component composition comprising components A and B. By using a large-molecule amine curing agent, the odor problem is solved at its source, and it exhibits good film-forming properties. However, the high activity of the curing agent results in a very short pot life (<1 hour), causing it to fail to meet the application time requirements in actual production. Summary of the Invention

[0008] Based on this, the purpose of the present invention is to overcome the defects or deficiencies of the prior art and provide a two-component composition, its preparation method and application. The two-component composition has a low odor, very fast hardness increase and early sandability establishment, excellent surface effect and flexibility, contains no organic solvent or has only a low content of organic solvent, and has an extremely long pot life. It can be widely used as a composition in wood sealing primers to improve the performance of wood coatings.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] This invention provides a two-component composition comprising component A and component B; wherein:

[0011] Component A comprises epoxy resin a1 and epoxy silane; in component A, the epoxy silane accounts for 18-80 wt% of the total weight of epoxy resin a1 and epoxy silane; epoxy resin a1 contains two epoxy groups; epoxy silane is a silane containing one epoxy group.

[0012] Component B comprises an adduct and an aminosilane; in Component B, the weight of the adduct accounts for 10-80 wt% of the total weight of the adduct and the aminosilane; the adduct is an addition product obtained by reacting epoxy resin b1 with aminosilane in a molar ratio of 1:2; the epoxy resin b1 contains two epoxy groups; the aminosilane in Component B and the aminosilane used to prepare the adduct each independently include at least one of the compounds of formula (1);

[0013]

[0014] R in equation (1) 1 R 2 R 3 Each can be methyl or ethyl.

[0015] Through repeated research, the inventors of this invention discovered that limiting the weight of the adduct in component B of this invention to 10-80 wt% of the total weight of the adduct and the aminosilane, and specifying that the adduct is an addition product obtained by reacting the epoxy resin and the aminosilane in a molar ratio of 1:2, results in a two-component composition with low odor, very rapid hardness increase and early sanding performance, excellent surface finish, flexibility, and an extremely long pot life. If the weight of the adduct is less than 10% of the total weight of the adduct and the aminosilane, the coating formed when the two-component composition is used as a wood sealing primer will be white, with reduced early sanding performance and a stronger odor. If the weight of the adduct is greater than 80% of the total weight of the adduct and the aminosilane, the hardening process of the coating formed when the two-component composition is used as a wood sealing primer will be significantly delayed, with both surface drying and hard drying times significantly prolonged, and reduced early sanding performance and pot life.

[0016] The adduct of the present invention is an addition product obtained by reacting the epoxy resin b1 with the aminosilane at a molar ratio of 1:2. The adduct has a moderate molecular weight, which can effectively regulate the activity of the aminosilane and reduce odor and irritation. At the same time, the adduct can effectively balance the drying rate and pot life of the two-component composition. The two-component composition obtained by combining the B component containing the adduct and the aminosilane with the A component has the characteristics of low odor and long pot life, excellent early sanding properties, and extremely fast hardness build-up. This is because the B component containing the adduct and the aminosilane contains a certain amount of high-density moisture-curable silane structure, and the adduct effectively regulates the activity of the active NH group that can react with the epoxy group in the epoxy resin a1 or the epoxy silane, thereby resulting in a faster reaction rate.

[0017] Furthermore, the inventors were surprised to find that component B, containing the adduct and the aminosilane, exhibits good compatibility with epoxy resin a1 in component A. If component A uses a liquid epoxy resin, the epoxy silane must account for 18-80 wt% of the total weight of epoxy resin a1 and the epoxy silane to achieve the desired effect. If component A uses a solid epoxy resin, the epoxy silane must be used to adjust the viscosity to a suitable level, wherein the epoxy silane accounts for 25-80 wt% of the total weight of epoxy resin a1 and the epoxy silane. If the proportion of epoxy silane is too low, insufficient hydrolysis may result in a whitening of the coating after drying and reduced sandability. Moreover, if the proportion of epoxy silane in component A is too high, the crosslinking density after hydrolysis will be too high, leading to poor coating flexibility.

[0018] The inventors of this invention have also discovered that the aminosilane in component B, and the compound structure of the aminosilane used to prepare the adduct, for example, the compound structure of formula (1), must contain only one amino group; if an aminosilane containing two amino groups is used, such as N The addition product obtained from -aminoethyl-γ-aminopropyltrimethoxysilane (CAS: 1760-24-3) contains an excessively high concentration of active NH that can react with epoxy groups (or the B component contains an excessively high concentration of active NH that can react with epoxy groups), which will lead to a decrease in the pot life of the two-component composition, and the coating film formed by the two-component composition will experience shrinkage and wrinkling.

[0019] The adduct and the aminosilane in component B are ultimately in a mixed state. In a preferred embodiment of the invention, the adduct and the aminosilane are added to component B in the form of a mixture prepared by reacting epoxy resin b1 with an excess of aminosilane under heating conditions. It is understood that in this process, since epoxy resin b1 contains two epoxy groups and the aminosilane is in excess, the mixture formed after the reaction of epoxy resin b1 with the excess aminosilane contains both the adduct product (i.e., the adduct) formed by the reaction of epoxy resin b1 and aminosilane in a molar ratio of 1:2, and the remaining unreacted aminosilane; the remaining aminosilane serves as the aminosilane in component B. The amount of aminosilane used is sufficient to ensure that the weight of the adduct in the final component B is 10-80 wt% of the total weight of the adduct and the aminosilane.

[0020] More preferably, the adduct and the aminosilane in component B (i.e., the mixture) are a mixture prepared by reacting epoxy resin b1 with an excess of aminosilane at 40-80°C for 0.5-60 h. The applicant also needs to clarify that, during the reaction of epoxy resin b1 and aminosilane, by using an excess of aminosilane and reacting at 40-80°C for 0.5-60 h, the epoxy resin b1 and aminosilane can react in a molar ratio of 1:2 to obtain the adduct (i.e., the adduct). Furthermore, the applicant needs to clarify that, theoretically, trace amounts of byproducts exist during this reaction (e.g., the adduct obtained by reacting epoxy resin b1 with aminosilane in a molar ratio of 1:1). Those skilled in the art will readily understand that their content is extremely small and negligible, and the present invention does not impose any limitations on their content. The adduct and the aminosilane are a mixture prepared by reacting the epoxy resin b1 with an excess of the aminosilane at 40-70°C for 0.5-30 h.

[0021] Furthermore, regarding the method for obtaining the weight ratio of the adduct to the total weight of the adduct and the aminosilane in the "mixture" obtained by the above preparation method, a preferred method in this invention is to calculate it based on the amount of raw materials used and the theoretical consumption and production of the reaction process; another preferred method is to use nuclear magnetic resonance (NMR) to determine the proportion of the adduct, which is a method that can be routinely performed by those skilled in the art (exemplary calculation methods are provided in specific embodiments).

[0022] In another preferred embodiment of the present invention, the adduct and the aminosilane are added to the B component separately; that is, the adduct can be prepared by first reacting the epoxy resin b1 with the aminosilane in a molar ratio of 1:2 (the reaction conditions are the same as those for the preparation described above), and then the adduct and the aminosilane are mixed during the preparation of the B component.

[0023] The above two methods do not represent a specific limitation of the present invention. The adduct and aminosilane in component B, regardless of the manner or form in which they are added to component B, are acceptable as long as they meet the following condition: "In component B, the weight of the adduct accounts for 10-80 wt% of the total weight of the adduct and the aminosilane; the adduct is an addition product obtained by reacting epoxy resin b1 with aminosilane in a molar ratio of 1:2." Furthermore, it should be noted that "the adduct is an addition product obtained by reacting epoxy resin b1 with aminosilane in a molar ratio of 1:2" specifically refers to the adduct being obtained by reacting epoxy resin b1 with aminosilane according to the above theoretical ratio, and does not represent a limitation on the specific preparation method of the adduct.

[0024] In a preferred embodiment of the present invention, the epoxy resin a1 in component A comprises at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, and hydrogenated bisphenol A epoxy resin. More preferably, considering the low cost and availability of the material, the epoxy resin a1 is preferably a bisphenol A epoxy resin. The epoxy resin a1 preferably used in the present invention is a bisphenol A epoxy resin, such as NPEL-128, NPEL-134, NPES-901, and NPES-904 from Nan Ya Plastics Manufacturing Co., Ltd., Taiwan.

[0025] As a preferred embodiment of the present invention, in component A, the epoxy silane is a silane containing an epoxy group; the epoxy silane includes at least one of the compounds of formula (2) and the compounds of formula (3);

[0026]

[0027] Wherein, R in equation (2) 4 R5 R 6 Each is independently methyl or ethyl, and the statistical average of x is 2-9; R in equation (3) 7 R 8 R 9 Each is independently methyl or ethyl, and the statistical average of y is 2-9.

[0028] As a more preferred embodiment of the present invention, considering the low cost and availability of materials, the epoxy silane is preferably 3-glycidoxypropyltrimethoxysilane (CAS: 2530-83-8) and / or 3-glycidoxypropyltriethoxysilane (CAS: 2602-34-8).

[0029] In a preferred embodiment of the present invention, in component A, the epoxy silane accounts for 25-80 wt% of the total weight of the epoxy resin a1 and the epoxy silane, more preferably 30-80 wt%. Adding a certain amount of the epoxy silane can reduce the viscosity of component A, reduce the amount of organic solvent used or eliminate the need for solvent, and also improve the compatibility between the epoxy resin a1 in component A and the adduct in component B.

[0030] In a preferred embodiment of the present invention, the aminosilane in component B and the aminosilane used to prepare the adduct are each independently at least one of 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane.

[0031] As a preferred embodiment of the present invention, in component B, the epoxy resin b1 includes at least one of the compounds of formula (4);

[0032]

[0033] In formula (4), R is a divalent C2-C25 hydrocarbon group, or a group formed by at least one group of adjacent carbons on the carbon chain of a divalent C2-C25 hydrocarbon group being separated by O (e.g., -ORO- in the structure of formula (4) specifically forms a chain structure corresponding to a polydiol with hydrogen removed from both ends).

[0034] More preferably, the epoxy resin b1 is at least one selected from bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and butanediol diglycidyl ether. Preferably, the epoxy resin b1 used in this invention is a bisphenol A epoxy resin that is liquid at room temperature (such as NPEL-128 and NPEL-134 from Taiwan Nan Ya), or a hydrogenated bisphenol A epoxy resin (such as Hubei Green Home LS-518), or ethylene glycol diglycidyl ether (such as Hubei Green Home LS-669), polypropylene glycol diglycidyl ether (such as Hubei Green Home LS-227), or 1,4-butanediol diglycidyl ether (such as Hubei Green Home LS-622).

[0035] To facilitate a deeper understanding of the adduct of the present invention, the present invention uses "the adduct is an addition product obtained by reacting bisphenol A or / and bisphenol F epoxy resin b1 with the aminosilane in a molar ratio of 1:2" as an exemplary description. The adduct obtained by reacting bisphenol A or / and bisphenol F epoxy resin b1 with the aminosilane in a molar ratio of 1:2 (i.e., the adduct) has the structure shown in formula (5):

[0036]

[0037] Wherein, R in equation (5) 10 R 11 R 12 Each is independently methyl or ethyl; R 13 It is hydrogen or methyl; n is 1~10.

[0038] In a preferred embodiment of the present invention, the two-component composition may contain little or no organic solvent. When an organic solvent is selectively added to the two-component composition according to actual needs, component A and / or component B further include an organic solvent. Adding an organic solvent to component A and / or component B can improve the film-forming properties of the two-component composition, adjust the drying speed, and extend the pot life.

[0039] Furthermore, the weight of the organic solvent in component A and / or component B is 0.01-30 wt% of the total weight of the two-component composition. Excessive addition of the organic solvent will reduce the drying speed and increase the VOC content in the two-component composition system.

[0040] Further, the organic solvent is at least one selected from alcohol ethers, alcohols, ethers, esters, and ketone cosolvents. Preferably, the organic solvent is an alcohol ether solvent, such as dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, propylene glycol butyl ether, and ethylene glycol butyl ether.

[0041] Furthermore, the ratio of the total weight of the epoxy resin a1 and the epoxy silane in component A to the weight of the adduct and amino silane in component B is 1:(0.3-1.4). A ratio that is too high or too low will result in too many active NH groups on the epoxy groups or amino groups not participating in the crosslinking reaction, causing a decrease in crosslinking density and affecting the performance of the two-component composition as a wood sealing primer.

[0042] The present invention also provides the application of any of the above-described two-component compositions in wood (two-component) sealing primers.

[0043] By mixing component A with component B, the resulting two-component composition is applied directly to the wood substrate as a wood sealing primer.

[0044] Furthermore, the wood (two-component) sealing primer is a wood (two-component) sealing primer with low solvent content, having an organic solvent content of <20wt%, preferably <10wt%, and more preferably <5wt%.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The two-component composition of this invention has a long pot life, achieves dual curing, has high cross-linking density, low odor, and offers excellent surface finish, high hardness, early and overnight sandability, and flexibility. It contains no organic solvents or contains only low amounts of organic solvents. In particular, it improves the pot life while maintaining coating performance, solving the problem of imbalance between drying speed and pot life in previous products, allowing more time for actual production and application. It is especially suitable for wood sealing primers. Attached Figure Description

[0047] Figure 1 The NRM diagram of an example sample of the present invention (a mixture of an adduct C and an aminosilane);

[0048] Figure 2 The diagram shows the structural formulas of aminosilane and adduct C in the example sample; where formula A corresponds to aminosilane and formula B corresponds to adduct C. Detailed Implementation

[0049] The present invention is further illustrated below with reference to specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions in the art or as recommended by the manufacturer; the raw materials and reagents used, unless otherwise specified, are all commercially available from the conventional market. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention are within the scope of protection claimed by the present invention.

[0050] The raw materials used in the following examples or comparative examples:

[0051] (1) Epoxy resin:

[0052] ①Epoxy resin a1:

[0053] NPEL-128: Taiwan Nan Ya, bisphenol A epoxy resin (liquid), epoxy equivalent is approximately 184-190.

[0054] NPES-904: Taiwan Nan Ya, bisphenol A epoxy resin (solid), epoxy equivalent is approximately 780-850.

[0055] ②Epoxy resin b1:

[0056] NPEL-128: Taiwan Nan Ya, bisphenol A epoxy resin (liquid), epoxy equivalent is approximately 184-190.

[0057] LS-518: Hubei Green Home, hydrogenated bisphenol A epoxy resin, epoxy equivalent is approximately 217-238.

[0058] LS-669: Hubei Green Home, ethylene glycol diglycidyl ether, epoxy equivalent approximately 128-137.

[0059] LS-227: Hubei Green Home, polypropylene glycol diglycidyl ether, epoxy equivalent approximately 625-910.

[0060] LS-622: Hubei Green Home, 1,4-Butanediol diglycidyl ether, epoxy equivalent approximately 120-137.

[0061] (2) Epoxysilane:

[0062] GX-560: Anhui Sibao, 3-glycidyl etheroxypropyltrimethoxysilane, CAS: 2530-83-8.

[0063] (3) Aminosilane:

[0064] GX-540: Anhui Sibao, 3-aminopropyltrimethoxysilane, CAS: 13822-56-5.

[0065] GX-550: Anhui Sibao, 3-aminopropyltriethoxysilane, CAS: 919-30-2.

[0066] GX-792: Anhui Sibao, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, CAS: 1760-24-3 (Note: This aminosilane contains two amino groups and does not belong to the compounds of formula (1) as defined in this invention).

[0067] (4) A mixture of adduct C and aminosilane:

[0068] For the adduct and aminosilane in component B of the present invention, they are ultimately in a mixed state in component B. Therefore, the adduct C and aminosilane in component B of the embodiments of the present invention and some comparative examples (Comparative Examples 1-5) are "mixtures" prepared by epoxy resin b1 and excess aminosilane under heating conditions. It can be understood that the mixture contains both the addition product (i.e., adduct C) of epoxy resin b1 and aminosilane reacting in a molar ratio of 1:2, and the remaining unreacted aminosilane; the remaining aminosilane is then used as the aminosilane in component B.

[0069] For the content percentage of adducts in the mixture of adduct C and aminosilane:

[0070] In some methods, nuclear magnetic resonance (NMR) is used to determine the proportion of adducts. The following provides an illustrative measurement and calculation method: The sample is a "mixture" of an adduct C and an aminosilane prepared by heating an epoxy resin b1 with an excess of an aminosilane. The method for determining the content of adduct C in this mixture using NMR is as follows:

[0071] NMR apparatus: Bruker AVANCE NEO 500M;

[0072] Observation kernel: 1 H;

[0073] Waiting time: 5 seconds;

[0074] Cumulative: 32 times;

[0075] Solvent: CDCl3;

[0076] Measurement temperature: room temperature;

[0077] Chemical shift reference: TMS 0.00 ppm.

[0078] The sample was analyzed using the NMR apparatus and conditions described above. Please refer to the results. Figure 1 ;

[0079] Combination Figure 1 as well as Figure 2 Based on the structures of formulas A and B, the specific calculation method for the content of adduct C in this mixture is as follows:

[0080] Figure 2 The structures shown by a1 and a2 in equations A and B correspond to each other. Figure 1 The integral value X is located near 3.81 to 3.85 ppm.

[0081] Figure 2 The structures shown in equation B, b1 and b2, correspond. Figure 1 The integral value Y is around 7.09~7.13ppm and 6.78~6.82ppm.

[0082] Before the reaction, the aminosilane was 1 equivalent. For ease of calculation, the normalized integral value X = 6 was obtained after integration.

[0083] The percentage of adduct C in the total molar number of aminosilane and adduct C is approximately:

[0084]

[0085] In this sample:

[0086] The relative molar mass of adduct C is approximately 823 g / mol;

[0087] The relative molar mass of aminosilane is approximately 221 g / mol;

[0088] The percentage of adduct C in the total mass of aminosilane and adduct C is approximately:

[0089]

[0090] The above method is only an example. In actual operation, those skilled in the art can determine the content of adduct C in the mixture by NMR.

[0091] In another preferred embodiment, the content percentage of adduct C is calculated based on the amount of raw materials used and the theoretical consumption and production of the reaction process. This method is used in the following examples or comparative examples, specifically:

[0092] ①The mixture of adduct C and aminosilane in component B of Examples 1, 8, 13, Comparative Example 2, and 3 is specifically as follows:

[0093] The mixture of adduct C1 and aminosilane (38g GX-550) was prepared by adding 44.45g GX-550 (0.2008mol) and 5.55g NPEL-128 (0.0146mol) to a four-necked flask and reacting at 70℃ for 4h to obtain a pale yellow transparent liquid, which is a mixture of about 12g adduct C1 and about 38g GX-550.

[0094] In addition, the mixture of adduct C and aminosilane in component B of Examples 9, 10, 11, 12, Comparative Example 4, and Comparative Example 5 is specifically a mixture of adduct C1 and aminosilane (38g GX-550) with different contents (see Table 1 for details). The preparation method is to adjust the amount of raw materials according to the above preparation method, and will not be described in detail here.

[0095] ②The mixture of adduct C and aminosilane in component B of Example 2 is specifically as follows:

[0096] The mixture of adduct C2 and aminosilane (GX-540) was prepared by adding 43.81g of GX-540 (0.2444mol) and 6.19g of NPEL-128 (0.0163mol) to a four-necked flask and reacting at 70°C for 4h to obtain a pale yellow transparent liquid, which is a mixture of about 12g of adduct C2 and about 38g of GX-540.

[0097] ③ The mixture of adduct C and aminosilane in component B of Example 3 is specifically as follows:

[0098] The mixture of adduct C4 and aminosilane (GX-550) was prepared by adding 40.61 g of GX-550 (0.1834 mol) and 9.39 g of LS-227 (0.0061 mol) to a four-necked flask and reacting at 70 °C for 4 h to obtain a pale yellow transparent liquid, which is a mixture of about 12 g of adduct C4 and about 38 g of GX-550.

[0099] ④ The mixture of adduct C and aminosilane in component B of Example 4 is specifically as follows:

[0100] The mixture of adduct C5 and aminosilane (GX-550) was prepared by adding 46.61g of GX-550 (0.2106mol) and 3.39g of LS-669 (0.0195mol) to a four-necked flask and reacting at 70℃ for 4h to obtain a pale yellow transparent liquid, which is a mixture of about 12g of adduct C5 and about 38g of GX-550.

[0101] ⑤ The mixture of adduct C and aminosilane in component B of Example 5 is specifically as follows:

[0102] The mixture of adduct C6 and aminosilane (GX-550) was prepared by adding 43.90 g of GX-550 (0.1983 mol) and 6.10 g of LS-518 (0.0134 mol) to a four-necked flask and reacting at 70 °C for 4 h to obtain a pale yellow transparent liquid, which is a mixture of about 12 g of adduct C6 and about 38 g of GX-550.

[0103] ⑥ The mixture of adduct C and aminosilane in component B of Examples 6 and 7 is specifically as follows:

[0104] The mixture of adduct C7 and aminosilane (GX-550) was prepared by adding 45.62 g of GX-550 (0.2060 mol) and 4.38 g of LS-622 (0.0173 mol) to a four-necked flask and reacting at 70 °C for 4 h to obtain a pale yellow transparent liquid, which is a mixture of about 12 g of adduct C7 and about 38 g of GX-550.

[0105] ⑦ The mixture of adduct C and aminosilane in component B of Comparative Example 1 is specifically as follows:

[0106] The mixture of adduct C3 and aminosilane (GX-792) was prepared by adding 44.45g of GX-792 (0.1999mol) and 5.55g of NPEL-128 (0.0146mol) to a four-necked flask and reacting at 70°C for 4 hours to obtain a pale yellow transparent liquid, which is a mixture of about 12g of adduct C3 and about 38g of GX-792.

[0107] (5) Organic solvents:

[0108] DPM: Dow Chemical, dipropylene glycol monomethyl ether, CAS: 34590-94-8.

[0109] (6) Substituted phenols:

[0110] DMP-30: 2,4,6-tris(dimethylaminomethyl)phenol, CAS: 90-72-2.

[0111] Examples 1-13

[0112] Examples 1-13 each provide a two-component composition, comprising component A and component B.

[0113] For details regarding the composition of components A and B, as well as the specific selection and mass of each component in the two-component compositions of each embodiment, please refer to Table 1.

[0114] For the two-component compositions of each embodiment, please refer to Table 2 for the following proportions: the weight of epoxy silane in component A relative to the total weight of epoxy resin a1 and epoxy silane; the weight of adduct C in component B relative to the total weight of adduct C and aminosilane; the content of organic solvent in the two-component composition; and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of adduct C and aminosilane in component B.

[0115] Examples 1-13 also provide a method for preparing a two-component composition, comprising the following steps: mixing the substances of component A according to the formula at 25±2℃ to obtain component A, mixing the substances of component B according to the formula to obtain component B, and mixing component A and component B to obtain a two-component composition.

[0116] Comparative Examples 1-5

[0117] Comparative Examples 1-5 each provide a two-component composition comprising component A and component B.

[0118] For the comparative examples of two-component compositions, please refer to Table 1 for the material composition of component A and component B, as well as the specific selection and mass of each substance.

[0119] For each comparative example of two-component compositions, please refer to Table 2 for the following proportions: the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane; the weight ratio of adduct C in component B to the total weight of adduct C and aminosilane; the content of organic solvent in the two-component composition; and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of adduct and aminosilane in component B.

[0120] The preparation method of the two-component compositions of Comparative Examples 1-5 includes the following steps: at 25±2℃, the substances of component A are mixed according to the formula to obtain component A, the substances of component B are mixed according to the formula to obtain component B, and component A and component B are mixed to obtain the two-component composition.

[0121] Comparative Example 6

[0122] Comparative Example 6 provides a two-component composition comprising component A and component B; wherein,

[0123] Component A includes epoxy resin a1 (NPEL-128, 60g) and epoxy silane (GX-560, 40g).

[0124] Component B includes aminosilane (GX-550, 50g).

[0125] In this comparative example of a two-component composition, the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane is 40%, no adducts are added in component B, the content of organic solvent in the two-component composition is 0, and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of amino silane in component B is 1:0.5.

[0126] The preparation method of the comparative example two-component composition includes the following steps: mixing the substances of component A according to the formula at 25±2℃ to obtain component A, and mixing component A and component B to obtain the two-component composition.

[0127] Comparative Example 7

[0128] Comparative Example 7 provides a two-component composition formulated according to Example 1 of patent CN120271791A.

[0129] Specifically, the two-component composition of Comparative Example 7 comprises component A and component B; wherein:

[0130] Component A includes epoxy resin a1 (NPEL-128, 60g) and epoxy silane (GX-560, 40g).

[0131] Component B includes aminosilane (GX-550, 50g) and substituted phenol (DMP-30, 2g).

[0132] In this comparative example of a two-component composition, the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane is 40%, no adducts are added in component B, the content of organic solvent in the two-component composition is 0, and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of aminosilane and substituted phenol in component B is 1:0.52.

[0133] The preparation method of the comparative example two-component composition includes the following steps: at 25±2℃, the substances of component A are mixed according to the formula to obtain component A, the substances of component B are mixed according to the formula to obtain component B, and components A and B are mixed to obtain the two-component composition.

[0134] Comparative Example 8

[0135] Comparative Example 8 provides a two-component composition formulated according to Example 1 of Patent CN121182303A.

[0136] Specifically, the two-component composition of Comparative Example 8 comprises component A and component B; wherein:

[0137] Component A includes epoxy resin (NPEL-128, 60g) and epoxy silane (GX-560, 40g).

[0138] Component B includes adduct D1 (Example 1 of the corresponding patent CN121182303A uses adduct C1; to avoid confusion in the numbering, this comparative example uses adduct D1 instead, 80g).

[0139] In this comparative example of a two-component composition, the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane is 40%, the weight ratio of adduct D1 in component B to the total weight of adduct D1 and aminosilane is 100%, the content of organic solvent in the two-component composition is 0%, and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of adduct D1 and aminosilane in component B is 1:0.8.

[0140] In this comparative example, the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane, the weight ratio of adduct in component B to the total weight of adduct and aminosilane, the content of organic solvent in the two-component composition, and the ratio of the total weight of epoxy resin a1 and epoxy silane in component A to the total weight of adduct and aminosilane in component B are shown in Table 2.

[0141] The preparation method of the comparative example two-component composition includes the following steps: at 25±2℃, the substances of component A are mixed according to the formula to obtain component A, and component A and component B are mixed to obtain the two-component composition.

[0142] Table 1. Formulations of two-component compositions in Examples 1-13 and Comparative Examples 1-5

[0143]

[0144] Table 2. Relevant proportion data of the two-component composition formulations of Examples 1-13 and Comparative Examples 1-5

[0145]

[0146] Performance testing

[0147] The two-component compositions of Examples 1-13 and Comparative Examples 1-8 were subjected to the following performance tests:

[0148] Application method: Sand the wood substrate with 240# sandpaper; apply the two-component compositions of Examples 1-13 and Comparative Examples 1-8 directly to the wood substrate as wood sealing primers at 25±2℃; after spraying, dry at 25±2℃.

[0149] Early sandability test: 6 hours after coating application, sand with 400# sandpaper and observe the amount of powder produced and the amount of sandpaper sticking. Score 1-5 points, with 5 points (more powder produced, no sandpaper sticking) being the best.

[0150] Overnight sandability test: After drying overnight (16h), sand with 400# sandpaper and observe the amount of powder produced and the amount of sandpaper sticking. Score 1-5 points, with 5 points (more powder produced, no sandpaper sticking) being the best.

[0151] Surface effect test: After the coating is completely dry, visually inspect whether the surface of the coating is transparent and smooth, and score it from 1 to 5 points, with 5 points (transparent and smooth) being the best.

[0152] Flexibility (thermal and cold cycling test): The two-component compositions of Examples 1-13 and Comparative Examples 1-8 were tested according to ASTM D1211. One cycle consisted of 50°C for one hour, room temperature for 0.5 hours, -20°C for one hour, and room temperature for 0.5 hours. The cycles were repeated 5 times. The coating was observed for cracking.

[0153] Pot life: The prepared two-component compositions of Examples 1-13 and Comparative Examples 1-8 were stored at 25±2℃, and the viscosity was measured every hour. The time when the viscosity doubled was the pot life.

[0154] Odor test: Smell the two-component compositions of Examples 1-13 and Comparative Examples 1-8 with your nose and score them from 1 to 5, with 5 being the lowest odor score.

[0155] Please refer to Table 3 for the test results:

[0156] Table 3 Performance Test Results

[0157]

[0158] The performance test results in Table 3 show that the two-component compositions of Examples 1-13 of the present invention, when sprayed as wood sealing primers onto the surface of wood substrates, form coatings with excellent surface effects, overnight sanding properties, early sanding properties, and flexibility, and have an extremely long pot life, which facilitates operation in the production process of downstream enterprises and reduces the waste of raw materials.

[0159] In the two-component composition of Comparative Example 1, the adduct and aminosilane in component B are produced by reacting epoxy resin b1 with an excess of "aminosilane containing two amino groups ( N The mixture of adduct C3 obtained by the reaction of "-aminoethyl-γ-aminopropyltrimethoxysilane" and "aminosilane containing two amino groups" has an excessively high concentration of active NH in component B that can react with epoxy groups. This results in a relatively short pot life for the two-component composition of Comparative Example 1. Furthermore, when the two-component composition of Comparative Example 1 is used as a wood sealing primer, the early sanding and overnight sanding properties of the coating are relatively poor. After film formation, the surface effect of the coating is poor (shrinkage and wrinkling occur) and the flexibility is poor (the coating cracks after the hot and cold cycle test).

[0160] In the two-component composition of Comparative Example 2, the weight ratio of epoxy silane in component A to the total weight of epoxy resin a1 and epoxy silane is 15% (lower than the minimum limit of 18% specified in this invention). When the two-component composition of Comparative Example 2 is used as a wood sealing primer, the pot life is shortened, the film hardening process is significantly delayed, both surface drying and hard drying time are extended, and the early sanding and overnight sanding properties of the film are poor. After film formation, the surface effect of the film is poor (the surface is white and wrinkled defects appear) and the flexibility is poor (the film cracks after the hot and cold cycle test).

[0161] In the two-component composition of Comparative Example 3, no epoxy silane was added to component A. When the two-component composition of Comparative Example 3 was used as a wood sealing primer, the pot life was significantly shortened, the film hardening process was significantly delayed, the surface drying and hard drying times were significantly prolonged, and the early sanding and overnight sanding properties of the film were poor. After film formation, the surface effect of the film was poor (severe whitening and obvious shrinkage defects) and the flexibility was poor (the film cracked after the cold and heat cycle test).

[0162] In the two-component composition of Comparative Example 4, the weight of adduct C1 in component B accounts for 85% of the total weight of adduct C1 and aminosilane (exceeding the maximum limit of 80 wt% defined in this invention). When the two-component composition of Comparative Example 4 is used as a wood sealing primer, although the film-forming effect is good, the film hardening process is significantly delayed, the surface drying and hard drying times are significantly prolonged, the early sanding properties and pot life are significantly reduced, and it no longer meets the requirements of production and construction. This further illustrates the importance of the adduct of this invention for the establishment of film performance under specific equivalents.

[0163] In the two-component composition of Comparative Example 5, the weight of adduct C1 in component B accounts for 2% of the total weight of adduct C1 and aminosilane (lower than the minimum limit of 10 wt% specified in this invention). When the two-component composition of Comparative Example 5 is used as a wood sealing primer, the odor is significantly stronger, the early sanding properties of the coating are poor, and the surface effect of the coating is poor (the coating turns white). This further illustrates the importance of the adduct of this invention for the establishment of coating performance at specific equivalent amounts.

[0164] In the two-component composition of Comparative Example 6, no adduct was added to component B, which consisted only of aminosilane. When the two-component composition of Comparative Example 6 was used as a wood sealing primer, it had a strong odor, reduced early sandability of the coating film, and poor surface finish (whitening of the coating film). This further illustrates the importance of the adduct of the present invention for the establishment of coating film performance.

[0165] In the two-component composition of Comparative Example 7, no adduct was added to component B; instead, small-molecule aminosilanes and substituted phenols were used directly as component B. The two-component composition of Comparative Example 7 had a very strong odor.

[0166] In the two-component composition of Comparative Example 8, only the adduct of Example 1 of Patent CN121182303A is used in Component B. When the two-component composition of Comparative Example 8 and the two-component composition of Comparative Example 7 are used as wood sealing primers, the pot life is very short (less than 1 hour), which is not conducive to construction in actual production processes.

[0167] Furthermore, it should be noted that a certain amount of epoxy silane must be added to component A of this invention to improve compatibility and obtain a good coating effect. If component A is a liquid epoxy resin (e.g., Examples 1-12), the weight of the epoxy silane should be 18-80 wt% of the total weight of the epoxy resin a1 and the epoxy silane to achieve the effects of this invention, resulting in a good surface finish after the two-component composition is applied as a wood sealing primer. If component A is a solid epoxy resin (e.g., Example 13), the epoxy silane must be used to adjust the viscosity to a suitable level, wherein the weight of the epoxy silane should be 25-80 wt% of the total weight of the epoxy resin a1 and the epoxy silane. Furthermore, as the proportion of epoxy silane increases further, the coating appearance will gradually improve, and the sanding properties and pot life will also improve simultaneously. A certain amount of epoxy silane must be added to component A of this invention to improve compatibility and obtain a good coating effect.

[0168] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and the present invention also intends to include these modifications and variations.

Claims

1. A two-component composition, characterized in that: It contains component A and component B; wherein: Component A comprises epoxy resin a1 and epoxy silane; in component A, the epoxy silane accounts for 18-80 wt% of the total weight of epoxy resin a1 and epoxy silane; epoxy resin a1 contains two epoxy groups; epoxy silane is a silane containing one epoxy group. Component B comprises an adduct and an aminosilane; in Component B, the weight of the adduct accounts for 10-80 wt% of the total weight of the adduct and the aminosilane; the adduct is an addition product obtained by reacting epoxy resin b1 with aminosilane in a molar ratio of 1:2; the epoxy resin b1 contains two epoxy groups; the aminosilane in Component B and the aminosilane used to prepare the adduct each independently include at least one of the compounds of formula (1); R in equation (1) 1 R 2 R 3 Each can be methyl or ethyl.

2. The two-component composition according to claim 1, characterized in that: The adduct and the aminosilane are added to component B in the form of a mixture, which is prepared by reacting the epoxy resin b1 with an excess of the aminosilane at 40-80°C for 0.5-60 h.

3. The two-component composition according to claim 1, characterized in that: The epoxy silane includes at least one of the compounds of formula (2) and the compounds of formula (3); Wherein, R in equation (2) 4 R 5 R 6 Each is independently methyl or ethyl, and the statistical average of x is 2-9; R in equation (3) 7 R 8 R 9 Each is independently methyl or ethyl, and the statistical average of y is 2-9.

4. The two-component composition according to claim 1, characterized in that: In component A, the weight of the epoxy silane accounts for 25-80 wt% of the total weight of the epoxy resin a1 and the epoxy silane.

5. The two-component composition according to claim 1, characterized in that: The epoxy resin b1 includes at least one of the compounds of formula (4); In formula (4), R is a divalent C2-C25 hydrocarbon group, or a group formed by at least one group of adjacent carbons on the carbon chain of a divalent C2-C25 hydrocarbon group being separated by O.

6. The two-component composition according to claim 1 or 5, characterized in that: The epoxy resin a1 includes at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, and hydrogenated bisphenol A epoxy resin. The epoxy resin b1 includes at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and butylene glycol diglycidyl ether.

7. The two-component composition according to claim 1, characterized in that: The A component and / or the B component further contain an organic solvent, the weight of which is 0.01-30 wt% of the total weight of the two-component composition.

8. The two-component composition according to claim 1, characterized in that: The ratio of the total weight of the epoxy resin a1 and the epoxy silane in component A to the total weight of the adduct and the amino silane in component B is 1:(0.2-1.6).

9. A method for preparing a two-component composition according to any one of claims 1-8, characterized in that: Includes the following steps: The two-component composition is obtained by mixing component A and component B.

10. The use of a two-component composition as described in any one of claims 1-8 in a wood sealing primer.

Images