An acrylic modified polysiloxane / hexagonal boron nitride composite heat-conducting anticorrosive coating and a preparation method thereof

Abstract

The application belongs to the technical field of paint, and discloses a kind of acrylic modified polysiloxane / hexagonal boron nitride composite heat-conducting anticorrosive paint and preparation method thereof.The heat-conducting anticorrosive paint includes the following components by mass fraction: 60-80 parts of acrylic modified polysiloxane resin, 4-20 parts of modified hexagonal boron nitride, and 6-15 parts of curing agent.The application effectively improves the interfacial bonding force between h-BN particles and polymer matrix by surface functionalization modification of hexagonal boron nitride, promotes the rapid transfer of heat along the filler network, and combines the surface functionalization treated hexagonal boron nitride with acrylic modified polysiloxane to obtain a composite heat-conducting anticorrosive paint;the acrylic modified polysiloxane resin and the modified hexagonal boron nitride have a synergistic effect, and the obtained heat-conducting anticorrosive paint has excellent heat-conducting efficiency and corrosion protection ability.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to an acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating and its preparation method. Background Technology

[0002] With the advancement of technology and the growth of industrial demands, the requirements for material performance are becoming increasingly stringent. Especially in fields such as electronic equipment, aerospace, and automotive manufacturing, materials are required not only to have good thermal conductivity to ensure effective heat dissipation but also excellent corrosion resistance to extend service life. Traditional single materials often struggle to meet these demanding conditions simultaneously; therefore, developing novel composite materials has become one of the effective ways to solve this problem.

[0003] Acrylic-modified polysiloxanes, as an important class of organosilicon materials, have broad application prospects in the coatings field. These materials combine the excellent mechanical strength and weather resistance of acrylic resins with the outstanding chemical resistance and low surface energy of polysiloxanes, resulting in good physical and mechanical properties and excellent protective effects. However, when used alone, their thermal conductivity is relatively weak, insufficient to meet the requirements of efficient heat dissipation in certain specific applications.

[0004] Hexagonal boron nitride (h-BN), as a two-dimensional material, has attracted widespread attention due to its unique structural properties. It possesses a layered structure similar to graphene, and its atomic arrangement gives h-BN excellent insulation and chemical stability, while also providing relatively high thermal conductivity. However, the poor compatibility of h-BN in its pristine state with polymer matrices limits its effectiveness in practical applications.

[0005] Therefore, it is of great significance to study an acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating with excellent physical properties, thermal conductivity, and corrosion resistance, as well as its preparation method. Summary of the Invention

[0006] In view of this, the present invention provides an acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating, the purpose of which is to solve the problems of poor physical properties, low thermal conductivity and poor corrosion resistance caused by poor interfacial bonding between h-BN particles and polymer matrix in the prior art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides an acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating, comprising the following components in parts by weight:

[0009] Acrylic-modified polysiloxane resin 60-80 parts, modified hexagonal boron nitride 4-20 parts, curing agent 6-15 parts.

[0010] Preferably, the acrylic-modified polysiloxane resin contains 10-20% silicon and the acrylate monomer is one or more of methyl methacrylate, butyl acrylate, and ethyl acrylate.

[0011] Preferably, the curing agent is γ-aminopropyltriethoxysilane or γ-aminopropyltrimethoxysilane.

[0012] Preferably, the preparation of the modified hexagonal boron nitride includes the following steps:

[0013] Hexagonal boron nitride was mixed with toluene to obtain a dispersion. Acrylic acid and an initiator were added to the dispersion, and the mixture was dried after the reaction to obtain modified hexagonal boron nitride.

[0014] Preferably, the particle size of the hexagonal boron nitride is 0.1–5 μm.

[0015] Preferably, the initiator is azobisisobutyronitrile.

[0016] Preferably, the ratio of hexagonal boron nitride to toluene is 1g:50-100mL;

[0017] The mass ratio of acrylic acid to initiator is 100:0.8-2;

[0018] The mass ratio of acrylic acid to hexagonal boron nitride is 10:0.8 to 1.5.

[0019] Preferably, the reaction temperature is 50–80°C and the reaction time is 5–8 hours.

[0020] Preferably, the drying temperature is 55-65°C and the drying time is 10-14 hours.

[0021] This invention also provides a method for preparing the aforementioned acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating, comprising the following steps:

[0022] An acrylic-modified polysiloxane resin, modified hexagonal boron nitride, and a curing agent are mixed to obtain a thermally conductive and corrosion-resistant coating.

[0023] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention effectively improves the interfacial bonding force between h-BN particles and the polymer matrix by surface functionalizing hexagonal boron nitride, promoting rapid heat transfer along the filler network. The surface-functionalized hexagonal boron nitride is combined with acrylic-modified polysiloxane to prepare a composite thermally conductive and anti-corrosion coating. The acrylic-modified polysiloxane resin and the modified hexagonal boron nitride have a synergistic effect, giving the obtained thermally conductive and anti-corrosion coating excellent thermal conductivity and anti-corrosion protection capabilities. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1 The image shows the SEM morphology of the thermally conductive and anti-corrosion coating obtained in Example 1 after coating.

[0027] Figure 2 The image shows the SEM morphology of the coating obtained in Comparative Example 1 after coating preparation.

[0028] Figure 3 The image shows the elemental distribution of the coating surface after the thermally conductive and anti-corrosion coating obtained in Example 1 is applied. Detailed Implementation

[0029] This invention provides an acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating, comprising the following components in parts by weight:

[0030] Acrylic-modified polysiloxane resin 60-80 parts, modified hexagonal boron nitride 4-20 parts, curing agent 6-15 parts.

[0031] In this invention, the mass fraction of the acrylic-modified polysiloxane resin is preferably 62-78 parts, more preferably 65-75 parts, and even more preferably 70-72 parts; the mass fraction of the modified hexagonal boron nitride is preferably 8-18 parts, more preferably 10-15 parts, and even more preferably 12-13 parts; and the mass fraction of the curing agent is preferably 7-14 parts, and even more preferably 8-10 parts.

[0032] In this invention, the silicon content in the acrylic-modified polysiloxane resin is preferably 10-20%, more preferably 12-18%, and even more preferably 15-16%, and the acrylate monomer is preferably one or more of methyl methacrylate, butyl acrylate, and ethyl acrylate.

[0033] In this invention, the curing agent is preferably γ-aminopropyltriethoxysilane or γ-aminopropyltrimethoxysilane.

[0034] In this invention, the preparation of the modified hexagonal boron nitride includes the following steps:

[0035] Hexagonal boron nitride was mixed with toluene to obtain a dispersion. Acrylic acid and an initiator were added to the dispersion, and the mixture was dried after the reaction to obtain modified hexagonal boron nitride.

[0036] In this invention, the particle size of the hexagonal boron nitride is preferably 0.1-5 μm, more preferably 1-4.2 μm, and even more preferably 2-3 μm.

[0037] In this invention, the initiator is preferably azobisisobutyronitrile (AIBN).

[0038] In this invention, the preferred ratio of hexagonal boron nitride to toluene is 1g:50-100mL, more preferably 1g:60-90mL, and even more preferably 1g:70-80mL;

[0039] The mass ratio of acrylic acid to initiator is preferably 100:0.8 to 2, more preferably 100:1 to 1.8, and even more preferably 100:1.2 to 1.6;

[0040] The mass ratio of acrylic acid to hexagonal boron nitride is preferably 10:0.8 to 1.5, more preferably 10:1 to 1.4, and even more preferably 10:1.1 to 1.2.

[0041] In this invention, the mixing is preferably ultrasonic dispersion or stirring dispersion. The ultrasonic dispersion power is preferably 120-180W, more preferably 130-170W, and even more preferably 140-150W. The ultrasonic dispersion time is preferably 0.5-2h, more preferably 1-1.5h. The stirring dispersion stirring rate is preferably 200-450rpm, more preferably 250-400rpm, and even more preferably 300-350rpm. The stirring dispersion time is preferably 20-90min, more preferably 30-70min, and even more preferably 50-60min.

[0042] The acrylic acid and initiator are preferably added by dropwise addition, and the dropwise addition rate is preferably 0.5 to 2 mL / min, more preferably 0.8 to 1.6 mL / min, and even more preferably 1 to 1.2 mL / min.

[0043] After the reaction, solid-liquid separation and washing are performed. The solid-liquid separation is preferably vacuum filtration, and the vacuum degree of the vacuum filtration is preferably ≤13.3 Pa, more preferably ≤10.1 Pa, and even more preferably ≤9 Pa. The washing reagent is preferably water, and the number of washings is preferably 3 to 6 times, more preferably 4 to 5 times.

[0044] In this invention, the reaction temperature is preferably 50-80°C, more preferably 55-75°C, and even more preferably 60-70°C; the reaction time is preferably 5-8 hours, more preferably 5.5-7.5 hours, and even more preferably 6-7 hours; the reaction is preferably carried out under stirring, and the stirring speed is preferably 150-300 rpm, more preferably 180-260 rpm, and even more preferably 200-250 rpm.

[0045] In this invention, the drying is preferably vacuum drying, with the vacuum degree preferably ≤13.3 Pa, more preferably ≤10.1 Pa, and even more preferably ≤9 Pa. The drying temperature is preferably 55-65°C, more preferably 58-64°C, and even more preferably 60-62°C. The drying time is preferably 10-14 h, more preferably 11-13 h, and even more preferably 12-12.5 h.

[0046] This invention also provides a method for preparing the aforementioned acrylic-modified polysiloxane / hexagonal boron nitride composite thermally conductive and anti-corrosion coating, comprising the following steps:

[0047] An acrylic-modified polysiloxane resin, modified hexagonal boron nitride, and a curing agent are mixed to obtain a thermally conductive and corrosion-resistant coating.

[0048] In this invention, the preferred mixing order is to add modified hexagonal boron nitride to the acrylic-modified polysiloxane resin, mix them evenly, and then add the curing agent.

[0049] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0050] In the embodiments and comparative examples of this invention, the acrylic-modified polysiloxane resin was produced by Kaifeng Quark New Materials Co., Ltd.

[0051] Example 1

[0052] 5g of hexagonal boron nitride (particle size 4.5μm) was ultrasonically dispersed with 500mL of toluene at a frequency of 150W for 1h to obtain a dispersion. 50g of acrylic acid and 1g of azobisisobutyronitrile were added dropwise to the dispersion at a rate of 1.2mL / min, and the mixture was stirred at 200rpm at 60℃ for 6h. After the reaction was completed, the mixture was vacuum filtered at a vacuum degree of 10.1Pa. The resulting filter residue was washed three times with water and then vacuum dried at 60℃ at a vacuum degree of 10.1Pa for 12h to obtain modified hexagonal boron nitride.

[0053] Add 1.5g of modified hexagonal boron nitride to 10g of acrylic modified polysiloxane resin (silicon content is 15%, acrylate monomer is butyl acrylate), mix well, then add 1g of γ-aminopropyltriethoxysilane, mix well to obtain a thermally conductive and anti-corrosion coating.

[0054] Example 2

[0055] The preparation steps for the modified hexagonal boron nitride are the same as in Example 1;

[0056] Add 0.5g of modified hexagonal boron nitride to 10g of acrylic modified polysiloxane resin (silicon content is 15%, acrylate monomer is butyl acrylate), mix well, then add 1g of γ-aminopropyltriethoxysilane, mix well to obtain a thermally conductive and anti-corrosion coating.

[0057] Example 3

[0058] The preparation steps for the modified hexagonal boron nitride are the same as in Example 1;

[0059] Add 2g of modified hexagonal boron nitride to 10g of acrylic modified polysiloxane resin (silicon content is 15%, acrylate monomer is butyl acrylate), mix well, then add 1g of γ-aminopropyltriethoxysilane, mix well to obtain thermally conductive and anti-corrosion coating.

[0060] Comparative Example 1

[0061] Compared with Example 1, the addition of modified hexagonal boron nitride is omitted, and the other steps are the same as in Example 1.

[0062] Comparative Example 2

[0063] Compared with Example 1, "modified hexagonal boron nitride" was replaced with "hexagonal boron nitride", and the other steps were the same as in Example 1.

[0064] Comparative Example 3

[0065] Compared with Example 1, "adding 1.5g of modified hexagonal boron nitride" was replaced with "adding 4.7g of modified hexagonal boron nitride", and the other steps were the same as in Example 1.

[0066] The performance of the thermally conductive and anti-corrosion coatings obtained in Examples 1-3 and the coatings obtained in Comparative Examples 1-3 was tested:

[0067] The thermally conductive and anti-corrosion coatings obtained in Example 1 and Comparative Example 1 were respectively coated on the surface of tinplate sheets with a coating thickness of 220 μm. After coating, the coatings were dried at a drying temperature of 30°C for 24 h, and the SEM morphology of the coatings was observed.

[0068] The SEM image of the thermally conductive and anti-corrosion coating obtained in Example 1 is shown below. Figure 1 As shown, the SEM morphology of the coating obtained in Comparative Example 1 is as follows. Figure 2 As shown. By Figure 1 and Figure 2 As can be seen, the surface of the coating obtained in Comparative Example 1 is dense and smooth, while the surface of the coating obtained in Example 1 is relatively rough, proving that the modified hexagonal boron nitride and the acrylic-modified polysiloxane resin were effectively combined in the coating obtained in Example 1.

[0069] The surface element distribution of the coating obtained from the thermally conductive and anti-corrosion coating of Example 1 was detected, and a surface element distribution map was obtained.

[0070] The elemental distribution diagram of the surface of the thermally conductive and anti-corrosion coating obtained in Example 1 is shown below. Figure 3 As shown. By Figure 3 It is evident that the coating contains elements such as C, N, O, Si, and B, including the C, N, O, and Si elements of the acrylic-modified polysiloxane resin and the B and N elements of hexagonal boron nitride, and the distribution is uniform, further proving that hexagonal boron nitride and acrylic-modified polysiloxane resin are effectively combined.

[0071] The thermally conductive and anti-corrosion coatings obtained in Examples 1-3 and the coatings obtained in Comparative Examples 1-3 were subjected to thermal conductivity tests and neutral salt spray resistance tests. The thermal conductivity was tested according to GB / T 25261-2018 "Reflective Thermal Insulation Coatings for Buildings", and the neutral salt spray resistance was tested according to GB / T 1771-2007 "Determination of Neutral Salt Spray Resistance of Paints and Varnishes". The test results are shown in Table 1.

[0072] The thermally conductive and anti-corrosion coatings obtained in Examples 1-3 and the coatings obtained in Comparative Examples 1-3 were subjected to aging tests. The test steps were as follows: the thermally conductive and anti-corrosion coatings obtained in Examples 1-3 and the coatings obtained in Comparative Examples 1-3 were subjected to ultraviolet aging for 3000 hours, and the gloss was tested respectively. The test results are shown in Table 1.

[0073] Table 1. Performance test results of the thermally conductive and anti-corrosion coatings obtained in Examples 1-3 and the coatings obtained in Comparative Examples 1-3.

[0074]

[0075]

[0076] As can be seen from Table 1, the thermally conductive and anti-corrosion coatings obtained in Examples 1 to 3 have excellent thermal conductivity, salt spray resistance, and aging resistance.

[0077] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An acrylic-modified polysiloxane / hexagonal boron nitride composite heat conductive anticorrosive coating, characterized by, The composition comprises the following components in mass fraction: 60-80 parts of acrylic modified polysiloxane resin, 4-20 parts of modified hexagonal boron nitride, and 6-15 parts of curing agent; The preparation of the modified hexagonal boron nitride comprises the following steps: The hexagonal boron nitride is mixed with toluene to obtain a dispersion liquid, acrylic acid and an initiator are added into the obtained dispersion liquid, and the modified hexagonal boron nitride is obtained after drying after reaction.

2. The acrylic modified polysiloxane / h-BN composite heat conductive anticorrosive coating according to claim 1, characterized in that, In the acrylic modified polysiloxane resin, the silicon content is 10-20%, and the acrylic ester monomer is one or more of methyl methacrylate, butyl acrylate and ethyl acrylate.

3. The acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to claim 2, characterized in that, The curing agent is gamma-aminopropyl triethoxysilane or gamma-aminopropyl trimethoxysilane.

4. The acrylic modified polysiloxane / h-BN composite heat conductive anticorrosive coating according to claim 1, characterized in that, The particle size of the hexagonal boron nitride is 0.1-5 μm.

5. The acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to claim 4, characterized in that, The initiator is azobis isobutyronitrile.

6. The acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to claim 5, characterized in that, The usage ratio of the hexagonal boron nitride to toluene is 1g: 50-100 mL; The mass ratio of the acrylic acid to the initiator is 100: 0.8-2; The mass ratio of the acrylic acid to the hexagonal boron nitride is 10: 0.8-1.

5.

7. The acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to claim 4 or 6, characterized in that, The reaction temperature is 50-80℃, and the reaction time is 5-8h.

8. The acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to claim 7, characterized in that, The drying temperature is 55-65℃, and the drying time is 10-14h.

9. The method for preparing the acrylic-modified polysiloxane / h-BN composite heat-conducting anticorrosive coating according to any one of claims 1-8, characterized in that, The preparation comprises the following steps: The acrylic modified polysiloxane resin, the modified hexagonal boron nitride and the curing agent are mixed to obtain the heat-conducting anticorrosive coating.

Images