Functional coating composition

Abstract

The invention provides a functional coating composition, and relates to the technical field of coatings. The functional coating composition is composed of a component A and a component B. The raw material components of the component A comprise aspartic ester resin and a functional pigment filler, and the aspartic ester resin contains first aspartic resin with an asymmetric structure. The functional coating composition provided by the invention can realize thick coating, and the adhesive force of the cured coating is good.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings and relates to a functional coating composition. Background Art

[0002] Aspartic acid ester polyurea, cured with an isocyanate curing agent, exhibits excellent weathering and corrosion resistance. Aspartic acid polyurea coatings have been widely used in the anti-corrosion field. By adding functional fillers to aspartic acid polyurea, various functional materials can be obtained, such as those with radar absorption, sound insulation, and thermal conductivity. For example, Chinese patent CN114085600A discloses a polyaspartic acid ester polyurea radar-absorbing coating. Radar absorbers are added to the aspartic acid polyurea raw materials. The coating exhibits characteristics such as low sagging during spraying, fast film drying, high coating strength, good elasticity, and excellent durability. Adhesion is a key performance characteristic of coatings, but existing aspartic acid polyurea coatings lack sufficient adhesion and have high viscosity, making them unsuitable for spraying (it is generally accepted that coatings with viscosities exceeding 1000 mPa.s are unsuitable for spraying). In addition, for coatings that need to be applied thickly, such as radar-absorbing coatings, the thickness usually reaches 1.5mm-2mm, so multiple coats are required. From the perspective of production efficiency, the thicker the coating, the fewer the coating times, and the higher the production efficiency.

[0003] Therefore, the above-mentioned prior art needs further improvement. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a functional coating composition.

[0005] The technical solutions of the present invention are as follows: A functional coating composition, consisting of component A and component B; The raw materials of component A include: aspartic acid ester resin and functional pigments and fillers; The aspartic acid ester resin contains the first aspartic acid resin represented by the following formula (1): (1) wherein R1 is C1-C3 alkyl, R2 is C4-C8 alkyl; R3 and R4 are independently selected from H or C1-C4 alkylmethyl, and R3 and R4 are not H at the same time; The B component is an isocyanate curing agent.

[0006] Preferably, both R3 and R4 are methyl; Or, the R3 is methyl, and the R4 is H; Or, the R3 is H, and the R4 is methyl.

[0007] Preferably, the weight ratio of the aspartic acid ester resin to the functional pigment and filler is 1:0.1-2.

[0008] Preferably, the functional pigment filler is selected from one or a combination of two or more of anti-corrosion fillers, wave-absorbing materials, sound-absorbing materials, conductive fillers, magnetic fillers and thermal conductive fillers.

[0009] More preferably, the absorbing material is selected from one or a combination of two or more of ferrite, carbonyl iron powder, sendust powder, hydroxyl iron powder, soft magnetic alloy, ultrafine soft magnetic metal powder and iron silicon chromium powder.

[0010] Preferably, the weight proportion of the first aspartic acid ester resin is not less than 50%.

[0011] Preferably, the aspartic acid ester resin further contains a second aspartic acid resin; The second aspart resin is selected from one or a combination of two or more of F420 resin, F220 resin, F330 resin and F421 resin of Feiyang Junyan Company; The weight proportion of the second aspartic acid ester resin in the aspartic acid ester resin does not exceed 50%.

[0012] Preferably, the sum of the weight of the aspartic acid ester resin and the functional pigment and filler accounts for no less than 80% of the weight of component A.

[0013] Preferably, the raw material components of component A further include one or a combination of two or more of an auxiliary agent and an organic solvent.

[0014] More preferably, the auxiliary agent is selected from one or a combination of two or more of a wetting agent, a leveling agent, an anti-aging agent, a defoaming agent, an anti-settling agent, an anti-yellowing agent, an anti-UV agent and a water absorbent.

[0015] The beneficial effects of the present invention are: (1) The aspartic acid ester resin used in the present invention contains first-grade aspartic acid resin, which has an asymmetric structure, has the characteristics of long working life and quick drying, and has low viscosity. The prepared coating composition is suitable for spraying process, and can achieve the technical effect of a film thickness of 200 μm or higher in one spraying, with high construction efficiency and good adhesion of the coating.

[0016] (2) The aspartic acid ester resin of component A further contains F420 resin, etc., which can further improve the performance of the coating composition, such as faster drying and thicker film thickness in one spraying. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is further illustrated and described below through specific implementation methods.

[0018] The present invention provides a functional coating composition, which consists of component A and component B; The raw materials of component A include: aspartic acid ester resin and functional pigments and fillers; The aspartic acid ester resin contains the first aspartic acid resin represented by the following formula (1): (1) wherein R1 is C1-C3 alkyl, R2 is C4-C8 alkyl; R3 and R4 are independently selected from H or C1-C4 alkylmethyl, and R3 and R4 are not H at the same time; Component B is an isocyanate curing agent.

[0019] In the functional coating composition of the present invention, the aspartic acid ester resin acts as a binder and undergoes cross-linking and curing under the action of an isocyanate curing agent to form a coating or a cured material. The functional pigments and fillers serve to impart functionality to the coating composition. The first aspartic acid ester resin contained in the aspartic acid ester resin is structurally asymmetric, and the two secondary amino groups are subjected to different steric hindrances and have different activities. The secondary amino group with low steric hindrance provides a quick-drying effect, while the secondary amino group with high steric hindrance provides a long pot life effect, thereby achieving both a long pot life and a quick-drying effect. Moreover, the first aspartic acid ester resin has a low viscosity, with a viscosity of no more than 350 mPa.s at 25°C. The viscosity of the functional coating composition prepared is also low, making the functional coating composition suitable for spraying construction processes and having good workability. Moreover, a film thickness of 200 μm or more can be achieved in one spraying, effectively improving construction efficiency.

[0020] The first aspartic acid ester can be obtained by reacting the cyclohexanediamine compound represented by the following formula (2) with a first dialkyl maleate (R1OCOCH=CHCOOR1) and a second dialkyl maleate (R2OCOCH=CHCOOR2), respectively. For example, the first aspartic acid ester can be obtained by reacting with the first dialkyl maleate and then with the second dialkyl maleate, or by reacting with the second dialkyl maleate and then with the first dialkyl maleate.

[0021] (2).

[0022] For example, the cyclohexanediamine compound represented by formula (2) may be 2,4-dimethyl-1,3-cyclohexanediamine, 2-methyl-1,3-cyclohexanediamine, 4-methyl-1,3-cyclohexanediamine, etc. For example, the first dialkyl maleate may be dimethyl maleate, diethyl maleate, di-n-propyl maleate, etc.; for example, the second dialkyl maleate may be dibutyl maleate, dihexyl maleate, dioctyl maleate, diisooctyl maleate, diisopentyl maleate, etc.

[0023] In some embodiments, R3 and R4 are both methyl; Or, R3 is methyl, R4 is H; Or, R3 is H and R4 is methyl.

[0024] In the present invention, the asymmetric structure of the first-stage asparagine resin can be derived from the difference between R1 and R2, and can further be derived from the difference between R3 and R4 on the intermediate cyclohexane structure, or the superposition of these two effects. For example, when R3 is a methyl group and R4 is H, the asymmetric structure of the first-stage asparagine resin is derived from the difference between R1 and R2; when both R3 and R4 are methyl groups, or when R3 is H and R4 is methyl, the asymmetric structure of the first-stage asparagine resin is derived from the difference between R1 and R2 and the difference between R3 and R4, with the dual effects superimposed. The asymmetric structure of the first-stage asparagine resin causes the two secondary amino groups to be subjected to different steric hindrances, resulting in different activities. The secondary amino group with greater steric hindrance has relatively lower activity, while the secondary amino group with less steric hindrance has relatively higher activity.

[0025] In some embodiments, the weight ratio of the aspartic acid resin to the functional pigment is 1:0.1-2. For example, the weight ratio can be any value among 1:0.1, 1:0.3, 1:0.5, 1:0.6, 1:0.8, 1:1, 1:1.2, 1:1.4, 1:1.5, 1:1.7, 1:1.8, 1:2, etc., or any value in between, without particular limitation. Furthermore, the weight ratio of the aspartic acid resin to the functional pigment can be 1:0.5-2. The viscosity of the aspartic acid resin increases after adding functional pigments. Within a suitable range, the more functional pigments added, the stronger the functionality and the higher the viscosity. The first aspartic acid resin of the present invention has a low viscosity, so even if a large amount of functional pigments is added to the aspartic acid resin, it still has a low viscosity and good sprayability. However, if F420 resin, F520 resin, or the like is used alone, the viscosity is too high after adding a large amount of functional pigments, making it unsuitable for spraying.

[0026] In some embodiments, the functional pigments and fillers are selected from one or a combination of two or more of anti-corrosion fillers, wave-absorbing materials, sound-absorbing materials, conductive fillers, magnetic fillers, and thermally conductive fillers. The above-mentioned functional pigments and fillers can impart better functionality to the coating composition. For example, the anti-corrosion fillers can impart better corrosion resistance to the asparagus polyurea coating, the wave-absorbing materials can impart radar wave absorption properties to the asparagus polyurea coating, and the sound-absorbing materials can impart sound absorption and noise reduction properties to the asparagus polyurea coating. The above-mentioned functional pigments and fillers can be directly obtained from the market or prepared according to existing methods. Furthermore, the wave-absorbing materials are selected from one or a combination of two or more of ferrite, carbonyl iron powder, sendust powder, hydroxy iron powder, soft magnetic alloy, ultrafine soft magnetic metal powder, and iron silicon chromium powder, and can be directly obtained from the market.

[0027] In some embodiments, the weight proportion of the first aspartic acid resin in the aspartic acid resin is not less than 50%. If the weight proportion of the first aspartic acid resin in the aspartic acid resin is insufficient, the performance of the first aspartic acid resin cannot be fully utilized. For example, the weight proportion can be any value among 50%, 60%, 70%, 80%, 90%, 100%, etc., or any value therebetween, without particular limitation. Furthermore, the weight proportion of the first aspartic acid resin in the aspartic acid resin can be not less than 70%.

[0028] In some embodiments, the aspartic acid ester resin further comprises a second aspartic acid resin; The second day winter resin is selected from one or a combination of two or more of F420 resin, F220 resin, F330 resin and F421 resin produced by Feiyang Junyan Company; The second aspartic acid ester resin accounts for no more than 50% by weight of the aspartic acid ester resin.

[0029] The combination of the first aspartate resin and the second aspartate resin in the aspartic acid ester resin can give the aspartic acid ester resin one or more better properties. For example, the addition of F420 resin can further shorten the drying time, making it more conducive to the construction of multiple spray coats. The film thickness of a single spray coat can also be increased, improving construction efficiency. The weight proportion of the second aspartate resin in the aspartic acid ester resin should not be too high, otherwise it will affect the performance of the first aspartate resin. However, from the perspective of performance selection, when it is necessary to highlight one or more properties, the weight proportion of the second aspartate resin in the aspartic acid ester resin can be appropriately increased. For example, the weight proportion can be any value among 50%, 40%, 30%, 20%, 10%, 0%, etc., or any value in between, without special restrictions.

[0030] In some embodiments, the combined weight of the aspartic acid ester resin and the functional pigments and fillers accounts for no less than 80% of the weight of component A, thereby better enhancing the performance of the functional aspartic acid coating composition. Furthermore, the combined weight of the aspartic acid ester resin and the functional pigments and fillers accounts for no more than 98% of the weight of component A. For example, the combined weight of the aspartic acid ester resin and the functional pigments and fillers may account for any value among 80%, 82%, 85%, 88%, 90%, 92%, 93%, 95%, 97%, 98%, or any value in between, without particular limitation.

[0031] In some embodiments, the raw materials of Component A further include one or a combination of two or more of an additive and an organic solvent. Additives can optimize the properties of the coating composition, such as improved leveling, wettability, defoaming, and yellowing resistance. Organic solvents can further reduce the viscosity of the coating composition, facilitating the miscibility of the various raw material components and the application process. Furthermore, the additives are selected from one or a combination of two or more of a wetting agent, a leveling agent, an anti-aging agent, a defoamer, an anti-settling agent, an anti-yellowing agent, an anti-UV agent, and a water absorbent, all of which are commercially available. The organic solvent may be xylene, butyl acetate, or propylene glycol methyl ether acetate (PMA). The amount of organic solvent added may not exceed 5% by weight of Component A to achieve a high solids content (≥90%, or ≥95%) in the coating composition.

[0032] There are no particular limitations on the isocyanate curing agent in component B, which can be obtained directly from the market, such as HT-600, HT-100, HI-100, TPA-100, GB963B-100, etc. The amount of the isocyanate curing agent added to component B can be adjusted to a molar ratio of 1:1.03-1.15 between the NH groups in component A and the NCO groups in component B.

[0033] The preparation method of the functional coating composition of the present invention is not particularly limited and can be prepared according to conventional methods. For example, one preparation method can be: after the aspartic acid ester resin and the functional pigment and filler are mixed and dispersed evenly, various additives are added and dispersed evenly, and then an organic solvent is added and dispersed evenly to obtain the functional coating composition.

[0034] The technical solution of the present invention is further described and illustrated below based on various embodiments.

[0035] Preparation Example 1-2 Preparation of First Asparagus Resin Preparation Example 1 The molar ratio of 4-methyl-1,3-cyclohexanediamine, di-n-butyl maleate and diethyl maleate is 1:1.05:1.05.

[0036] At room temperature, 4-methyl-1,3-cyclohexanediamine was added to a reaction vessel, the temperature of the reaction system was controlled not to exceed 40°C, di-n-butyl maleate was added dropwise, and after the addition, the temperature was raised to 40-45°C and the reaction was carried out for 24 hours; diethyl maleate was added dropwise, and after the addition, the temperature was raised to 50-55°C and the reaction was carried out for 96 hours, and the reaction was continued at 55-60°C for 48 hours to obtain the first day asparagus resin. The viscosity at 25°C was measured by an NDJ-5S rotational viscometer to be 186 mPa.s.

[0037] Preparation Example 2 The molar ratio of 2,4-dimethyl-1,3-cyclohexanediamine, di-n-butyl maleate and diethyl maleate is 1:1.08:1.02.

[0038] At room temperature, 2,4-dimethyl-1,3-cyclohexanediamine was added to a reaction vessel, the temperature of the reaction system was controlled not to exceed 40°C, di-n-butyl maleate was added dropwise, and after the addition was complete, the temperature was raised to 40-45°C for reaction for 24 hours, and then the temperature was raised to 55-60°C for reaction for 24 hours; diethyl maleate was added dropwise, and after the addition was complete, the temperature was raised to 50-55°C for reaction for 96 hours, and the temperature was continued to be 55-60°C for 48 hours to obtain the first day asparagus resin. The viscosity at 25°C was measured by an NDJ-5S rotational viscometer to be 260 mPa.s.

[0039] Example 1 The functional coating composition of this embodiment is an absorbing coating composition, which is composed of component A and component B with a molar ratio of NH groups to NCO groups of 1:1.05.

[0040] Component A is composed of 35% of the first aspartame resin obtained in Preparation Example 1, 60% of ferrite absorbing material, 0.6% of polyether modified silicone oil leveling agent, 0.4% of dimethyl silicone oil defoaming agent, 2% of butyl acetate and 2% of PMA, based on 100% by weight.

[0041] Component B is HT-600.

[0042] The preparation method of the radar-absorbing coating composition comprises: adding a polyether-modified silicone oil leveling agent and a dimethyl silicone oil defoaming agent to a first-stage winter resin and stirring and dispersing them uniformly; then adding a ferrite radar-absorbing material and stirring and dispersing them uniformly at high speed; and finally adding an organic solvent and stirring uniformly to obtain component A. Components A and B are uniformly mixed to obtain the radar-absorbing coating composition.

[0043] Example 2 The difference between this example and Example 1 is that in Example 1, 35% of the first asparagine resin obtained in Preparation Example 1 was replaced with a combination of 28% of the first asparagine resin obtained in Preparation Example 1 and 7% of F420 resin. The remaining steps remained unchanged.

[0044] Example 3 The difference between this example and Example 1 is that in Example 1, 35% of the first asparagine resin obtained in Preparation Example 1 was replaced with a combination of 24.5% of the first asparagine resin obtained in Preparation Example 1 and 10.5% of F420 resin. The remaining steps remained unchanged.

[0045] Example 4 The difference between this example and Example 1 is that in Example 1, 35% of the first asparagine resin obtained in Preparation Example 1 was replaced with a combination of 17.5% of the first asparagine resin obtained in Preparation Example 1 and 17.5% of F420 resin. The remaining steps remained unchanged.

[0046] Example 5 The difference between this example and Example 1 is that in Example 1, 35% of the first asparagine resin obtained in Preparation Example 1 was replaced with a combination of 14% of the first asparagine resin obtained in Preparation Example 1 and 21% of F420 resin. The remaining steps remained unchanged.

[0047] Comparative Example 1 The difference between this comparative example and Example 1 is that in Example 1, the first asparagine resin is replaced with F420 resin in an equal weight ratio. The remaining steps remain unchanged.

[0048] Comparative Example 2 The difference between this comparative example and Example 1 is that in Example 1, the first asparagine resin is replaced with F520 resin in an equal weight ratio. The remaining steps remain unchanged.

[0049] Example 6 The functional coating composition of this embodiment is a sound-absorbing and noise-reducing coating composition, which is composed of component A and component B with a molar ratio of NH groups to NCO groups of 1:1.08.

[0050] Component A is 100% by weight and is composed of 45% of the first asparagus resin obtained in Preparation Example 2, 50% of D 50 It is composed of hollow glass microspheres with a particle size of 10 μm, 0.6% polyether modified silicone oil leveling agent, 0.4% dimethyl silicone oil defoaming agent, 1% butyl acetate and 3% PMA.

[0051] Component B consists of TPA-100.

[0052] Example 7 The difference between this example and Example 6 is that in Example 6, 45% of the first asparagine resin obtained in Preparation Example 2 was replaced by a combination of 36% of the first asparagine resin obtained in Preparation Example 2 and 9% of F420 resin. The remaining steps remained unchanged.

[0053] Comparative Example 3 The difference between this comparative example and Example 6 is that in Example 6, the first asparagus resin obtained in Preparation Example 2 is replaced with a combination of F420 resins in an equal weight ratio. The remaining steps remain unchanged.

[0054] The coating compositions of Examples 1-7 and Comparative Examples 1-3 were sprayed onto a clean tinplate surface and cured at room temperature for 7 days after spraying.

[0055] Performance testing Pot life: the time when the viscosity of the coating composition rises to 10,000 mPa.s when tested at 25°C.

[0056] Sprayability of the coating composition: Spray at 25°C and a spray pressure of 0.5 MPa, and observe whether the spraying is smooth. If smooth, indicate "√"; if not smooth, indicate "×".

[0057] Maximum thickness of one spray coat: the maximum spray film thickness when testing sag resistance according to the method of GB / T 9264-2012.

[0058] Surface drying time and through drying time: Tested in accordance with the method of GB / T 1728-2020. The surface drying time is accurate to 0.05h, and the through drying time is accurate to 0.5h.

[0059] Pull-off adhesion: tested according to the method of GB / T 5210-2019.

[0060] The results are shown in Table 1 below.

[0061] Table 1

[0062] As shown in Table 1, the functional coating composition of the present invention utilizes a first-stage winter resin having an asymmetric structure and low viscosity. The coating composition has low viscosity, making it suitable for spray coating processes. Furthermore, a single spray coating can achieve a film thickness of 200 μm or greater, and the cured coating exhibits good adhesion. Further optimization of the coating composition can achieve properties such as a long pot life, quick drying, a high single spray coating thickness, and good coating adhesion.

[0063] As described above, the basic principles, main features, and advantages of the present invention are shown and described. Those skilled in the art should understand that the present invention is not limited to the above-described embodiments. The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. In other words, equivalent changes and modifications made within the scope of the present invention and the contents of the specification should still fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A functional coating composition, characterized in that It consists of component A and component B; The raw materials of component A include: aspartic acid ester resin and functional pigments and fillers; The aspartic acid ester resin contains the first aspartic acid resin represented by the following formula (1): （1） wherein R1 is C1-C3 alkyl, R2 is C4-C8 alkyl; R3 and R4 are independently selected from H or C1-C4 alkylmethyl, and R3 and R4 are not H at the same time; The B component is an isocyanate curing agent.

2. The functional coating composition according to claim 1, wherein Said R3 and said R4 are both methyl; Or, the R3 is methyl, and the R4 is H; Or, the R3 is H, and the R4 is methyl.

3. The functional coating composition according to claim 1, wherein The weight ratio of the aspartic acid ester resin to the functional pigment and filler is 1:0.1-2.

4. The functional coating composition according to claim 1, wherein The functional pigment filler is selected from one or a combination of two or more of anti-corrosion fillers, wave-absorbing materials, sound-absorbing materials, conductive fillers, magnetic fillers and thermal conductive fillers.

5. The functional coating composition according to claim 4, characterized in that The absorbing material is selected from one or a combination of two or more of ferrite, carbonyl iron powder, sendust powder, hydroxy iron powder, soft magnetic alloy, ultrafine soft magnetic metal powder and iron silicon chromium powder.

6. The functional coating composition according to claim 1, characterized in that The weight proportion of the first aspartic acid ester resin is not less than 50%.

7. The functional coating composition according to claim 1, characterized in that The aspartic acid ester resin further contains a second aspartic acid resin; The second aspart resin is selected from one or a combination of two or more of F420 resin, F220 resin, F330 resin and F421 resin of Feiyang Junyan Company; The weight proportion of the second aspartic acid ester resin in the aspartic acid ester resin does not exceed 50%.

8. The functional coating composition according to claim 1, characterized in that The sum of the weight of the aspartic acid ester resin and the functional pigment and filler accounts for no less than 80% of the weight of component A.

9. The functional coating composition according to claim 1, characterized in that The raw material components of the A component further include one or a combination of two or more of an auxiliary agent and an organic solvent.

10. The functional coating composition according to claim 9, characterized in that The auxiliary agent is selected from one or a combination of two or more of a wetting agent, a leveling agent, an anti-aging agent, a defoaming agent, an anti-settling agent, an anti-yellowing agent, an anti-UV agent and a water absorbent.

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