High-damping wear-resistant coating and preparation method thereof

Abstract

The invention relates to a high-damping wear-resistant coating and a manufacturing method thereof. The high-damping wear-resistant coating comprises the following raw materials in parts by weight: 30-50 parts of modified polyurethane acrylate resin; 15 to 25 parts of core-shell structure microspheres; 10 to 20 parts of hybrid filler of boron nitride nanosheets and aluminum oxide nanowires; 3-5 parts of a silane coupling agent; 0.5 to 1 part of a defoaming agent; the preparation method comprises the following steps: carrying out ultrasonic treatment on boron nitride nanosheets and aluminum oxide nanowires in an ethanol medium for 30-40 minutes, and carrying out ball-milling mixing to obtain a hybrid filler; reacting the core-shell structure microspheres with a silane coupling agent at 75-85 DEG C for 1.5-2 hours to obtain surface modified microspheres; and stirring and mixing the modified polyurethane acrylate resin and the surface modified microspheres at the temperature of 55-65 DEG C at the rotating speed of 150-250 rpm for 1-1.5 hours. Damping and abrasion resistance are synchronously improved, through the synergistic effect of the core-shell microspheres and the hybrid filler, it is measured that tan delta reaches 0.51-0.55 at the temperature of 25 DEG C and is increased by 2.8 times compared with a pure polyurethane coating, Taber abrasion loss is only 38-45 mg / 1000 turns, corrosion resistance is remarkably improved, a salt spray test shows that after 2000 hours, the scratch corrosion width is smaller than or equal to 1.5 mm, and the adhesive force retention rate is 92%.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, in particular to a high-damping and wear-resistant coating and a manufacturing method thereof. Background Art

[0002] Damping coatings are formulated from polymer resins with appropriate amounts of fillers and auxiliary materials. They are a specialty coating that can be applied to various metal plate structures, providing vibration reduction, thermal insulation, and a certain degree of sealing. They are widely used for vibration reduction in aircraft, ships, vehicles, and various types of machinery. Because the coating can be sprayed directly onto the surface, it is easy to apply, making it particularly advantageous for complex structures such as those on ships and aircraft.

[0003] However, the prior art also has the following defects:

[0004] 1. Traditional damping coatings, such as acrylics, usually have a loss factor of <0.3 and poor wear resistance, with a wear loss of >100mg / 1000 revolutions;

[0005] 2. Wear-resistant coatings, such as polyurethane ceramic composite coatings, can reach a hardness of more than 3H, but the damping performance is insufficient, tanδ < 0.15;

[0006] 3. For example, the modified graphene oxide co-cured water-based epoxy resin coating and its preparation method proposed in Chinese patent 201910330031.6 uses graphene-enhanced epoxy resin coating. Although it improves wear resistance, it has the problem of uneven dispersion resulting in a decrease in damping performance of more than 20%.

[0007] Therefore, a high-damping wear-resistant coating and a manufacturing method thereof are proposed to solve the above problems. Summary of the Invention

[0008] In response to the shortcomings of the existing technology, the present invention provides a high-damping wear-resistant coating and a manufacturing method thereof, which has the advantages of high damping and wear resistance, and solves the problems of traditional damping coatings, such as acrylics, which usually have a loss factor of less than 0.3 and poor wear resistance, with a wear amount of more than 100 mg / 1000 revolutions; wear-resistant coatings, such as polyurethane ceramic composite coatings, which have a hardness of more than 3H but insufficient damping performance, with tanδ less than 0.15; and graphene-enhanced epoxy resin coatings, which improve wear resistance but have the problem of uneven dispersion resulting in a damping performance drop of more than 20%.

[0009] To achieve the above object, the present invention provides the following technical solution: a high-damping and wear-resistant coating, comprising the following raw materials in parts by weight:

[0010] Modified polyurethane acrylate resin: 30-50 parts;

[0011] Core-shell structure microspheres: 15-25 parts;

[0012] Hybrid filler of boron nitride nanosheets and aluminum oxide nanowires: 10-20 parts;

[0013] Silane coupling agent: 3-5 parts;

[0014] Defoaming agent: 0.5-1 part;

[0015] The particle size of the core-shell microspheres is 200-500 nm, and the shell layer contains carboxyl functional groups; the mass ratio of boron nitride nanosheets to aluminum oxide nanowires in the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is 3:1.

[0016] Furthermore, the modified polyurethane acrylate resin has a glass transition temperature of -20-60° C., and the molecular chain contains a hanging chain structure.

[0017] Furthermore, the core layer of the core-shell structured microspheres is composed of a copolymer of nitrile rubber and butyl acrylate, the butyl acrylate content accounts for 8-12% of the core layer mass, the shell layer is carboxylated polystyrene, the degree of carboxylation is 15-20%, the mass ratio of the core layer to the shell layer of the core-shell structured microspheres is 65:35±3%, and the shell layer thickness is 35-55nm.

[0018] Furthermore, the preparation method of the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is as follows:

[0019] 1) mixing boron nitride nanosheets and aluminum oxide nanowires in a mass ratio of (3.2-2.8):1;

[0020] 2) ultrasonic treatment in anhydrous ethanol at a power of 300-400 W for 40-50 minutes;

[0021] 3) then ball milling at 200-250 rpm for 2-3 hours using a planetary ball mill;

[0022] 4) The ball milling medium is zirconia beads with a diameter of 0.3-0.5 mm.

[0023] Furthermore, the preparation method of the modified polyurethane acrylate resin is as follows:

[0024] 1) polytetrahydrofuran diol and isophorone diisocyanate are reacted in a mol ratio of 1: (2.1-2.3),

[0025] 2) adding 4-6 wt% of hydroxyethyl methacrylate for end-capping,

[0026] 3) Finally, dodecyl mercaptan accounting for 1.5-2% of the resin solid content is introduced as a chain transfer agent.

[0027] A method for manufacturing a high-damping, wear-resistant coating, the manufacturing method being specifically as follows:

[0028] 1) ultrasonically treating boron nitride nanosheets and aluminum oxide nanowires in an ethanol medium for 30-40 minutes, and then ball milling to obtain a hybrid filler;

[0029] 2) reacting the core-shell structured microspheres with a silane coupling agent at 75-85° C. for 1.5-2 hours to obtain surface-modified microspheres;

[0030] 3) mixing the modified polyurethane acrylate resin and the surface-modified microspheres at 55-65° C. and 150-250 rpm for 1-1.5 hours;

[0031] 4) adding the hybrid filler to the mixture obtained in step 3), increasing the stirring speed stepwise to 1400-1500 rpm and maintaining it for 30±2 minutes;

[0032] 5) Degas the mixture at a vacuum degree of -0.07 to -0.09 MPa for 15 to 25 minutes.

[0033] Furthermore, the ultrasonic treatment frequency is 38-42 kHz, and the ball milling mixing uses zirconia ball milling beads, with a ball-to-material ratio of (5-8):1.

[0034] Furthermore, the temperature difference between step 3) and step 4) is controlled within the range of ±5°C.

[0035] Furthermore, the step-by-step improvement in step 4) is specifically as follows:

[0036] Stage 1: Disperse at 500-600 rpm for 5 minutes;

[0037] Second stage: dispersion at 800-900 rpm for 8 minutes;

[0038] The third stage: dispersion at 1200-1300 rpm for 5 minutes;

[0039] Final stage: Increase to 1450±50rpm and maintain for the remaining time.

[0040] Compared with the existing technology, the technical solution of this application has the following beneficial effects:

[0041] 1. This invention simultaneously enhances damping and wear resistance. Through the synergistic effect of core-shell microspheres and hybrid fillers, the tan delta measured at 25°C reaches 0.51-0.55, a 2.8-fold improvement compared to pure polyurethane coatings, and a Taber wear loss of only 38-45 mg / 1000 revolutions. Corrosion resistance is significantly improved, with salt spray testing showing scratch rust width ≤ 1.5 mm after 2000 hours, and adhesion retention of 92%.

[0042] 2. The nanofillers of the present invention are arranged in a directional manner. Boron nitride nanosheets are arranged in layers in parallel with a spacing of 50-80nm. Alumina nanowires are interspersed between the boron nitride sheets at an angle of 15-25° to form a three-dimensional interlocking structure, which improves the impact toughness by 40%. The core-shell microsphere-resin interface forms a C=O···Si-O-Si chemical bond. The hydroxyl density of the filler surface is increased from 12 / nm 2 Increased to 18 / nm 2 , the coating cohesion is improved and the peel strength reaches 8.2N / mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] Example 1

[0046] See also Figure 1 The high-damping and wear-resistant coating in this embodiment comprises the following raw materials in parts by weight:

[0047] Modified polyurethane acrylate resin: 30 parts;

[0048] Core-shell microspheres: 15 parts. The core layer of the core-shell microspheres is composed of a copolymer of nitrile rubber and butyl acrylate, with the butyl acrylate content accounting for 8% of the core layer's mass. The shell layer is carboxylated polystyrene with a carboxylation degree of 15%. The core-to-shell mass ratio of the core-shell microspheres is 65:35%, and the shell thickness is 35 nm.

[0049] Hybrid filler of boron nitride nanosheets and aluminum oxide nanowires: 10 parts;

[0050] Silane coupling agent: 3 parts;

[0051] Defoaming agent: 0.5 parts;

[0052] The particle size of the core-shell microspheres is 200nm, and the shell contains carboxyl functional groups; the mass ratio of boron nitride nanosheets to alumina nanowires in the hybrid filler of boron nitride nanosheets and alumina nanowires is 3:1; the glass transition temperature of the modified polyurethane acrylate resin is -20°C, and the molecular chain contains a hanging chain structure.

[0053] In this embodiment, the preparation method of the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is as follows:

[0054] 1) mixing boron nitride nanosheets and aluminum oxide nanowires at a mass ratio of 3.2:1;

[0055] 2) Ultrasonic treatment at 300 W in anhydrous ethanol for 40 minutes;

[0056] 3) then ball milled at 200 rpm for 2 hours using a planetary ball mill;

[0057] 4) The ball milling medium is zirconia beads with a diameter of 0.3 mm.

[0058] In this embodiment, the preparation method of the modified polyurethane acrylate resin is as follows:

[0059] 1) polytetrahydrofuran diol and isophorone diisocyanate are reacted in a mol ratio of 1:2.1,

[0060] 2) adding 4 wt% of hydroxyethyl methacrylate for end-capping,

[0061] 3) Finally, dodecyl mercaptan accounting for 1.5% of the resin solid content was introduced as a chain transfer agent.

[0062] The manufacturing method of high damping and wear-resistant coating is as follows:

[0063] 1) Boron nitride nanosheets and alumina nanowires were ultrasonically treated in ethanol for 30 minutes and then ball-milled to obtain a hybrid filler. The ultrasonic treatment frequency was 38 kHz, and zirconia balls were used for ball-to-bearing mixing at a ball-to-bearing ratio of 5:1.

[0064] 2) reacting the core-shell structured microspheres with a silane coupling agent at 75° C. for 1.5 h to obtain surface-modified microspheres;

[0065] 3) mixing the modified polyurethane acrylate resin and the surface-modified microspheres at 55° C. and 150 rpm for 1 h;

[0066] 4) Adding the hybrid filler to the mixture obtained in step 3), increasing the stirring speed stepwise to 1400 rpm and maintaining for 30 minutes, wherein the stepwise increase is as follows:

[0067] Stage 1: Dispersion at 500 rpm for 5 minutes;

[0068] Second stage: dispersion at 800 rpm for 8 minutes;

[0069] The third stage: dispersion at 1200 rpm for 5 minutes;

[0070] Final stage: Increase to 1450 rpm and maintain for the remaining time;

[0071] 5) Degas the mixture at a vacuum of -0.07 MPa for 15 min.

[0072] Example 2

[0073] See also Figure 1 The high-damping and wear-resistant coating in this embodiment comprises the following raw materials in parts by weight:

[0074] Modified polyurethane acrylate resin: 50 parts;

[0075] Core-shell microspheres: 25 parts. The core layer of the core-shell microspheres is composed of a copolymer of nitrile rubber and butyl acrylate, with the butyl acrylate content accounting for 12% of the core layer's mass. The shell layer is carboxylated polystyrene with a carboxylation degree of 20%. The core-to-shell mass ratio of the core-shell microspheres is 65:38%, and the shell thickness is 55 nm.

[0076] Hybrid filler of boron nitride nanosheets and aluminum oxide nanowires: 20 parts;

[0077] Silane coupling agent: 5 parts;

[0078] Defoaming agent: 1 part;

[0079] The particle size of the core-shell microspheres is 500nm, and the shell contains carboxyl functional groups; the mass ratio of boron nitride nanosheets to alumina nanowires in the hybrid filler of boron nitride nanosheets and alumina nanowires is 3:1; the glass transition temperature of the modified polyurethane acrylate resin is 60°C, and the molecular chain contains a hanging chain structure.

[0080] In this embodiment, the preparation method of the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is as follows:

[0081] 1) mixing boron nitride nanosheets and aluminum oxide nanowires at a mass ratio of 2.8:1;

[0082] 2) Ultrasonic treatment in anhydrous ethanol at a power of 400 W for 50 minutes;

[0083] 3) then ball milled at 250 rpm for 3 hours using a planetary ball mill;

[0084] 4) The ball milling medium is zirconia beads with a diameter of 0.5 mm.

[0085] In this embodiment, the preparation method of the modified polyurethane acrylate resin is as follows:

[0086] 1) polytetrahydrofuran diol and isophorone diisocyanate are reacted in a mol ratio of 1:2.3,

[0087] 2) adding 6 wt% of hydroxyethyl methacrylate for end-capping,

[0088] 3) Finally, dodecyl mercaptan accounting for 2% of the resin solid content was introduced as a chain transfer agent.

[0089] The manufacturing method of high damping and wear-resistant coating is as follows:

[0090] 1) Boron nitride nanosheets and alumina nanowires were ultrasonically treated in an ethanol medium for 40 minutes and then ball-milled to obtain a hybrid filler. The ultrasonic treatment frequency was 42 kHz, and zirconia ball milling beads were used for ball-to-bearing mixing at a ball-to-bearing ratio of 8:1.

[0091] 2) reacting the core-shell structured microspheres with a silane coupling agent at 85° C. for 2 h to obtain surface-modified microspheres;

[0092] 3) mixing the modified polyurethane acrylate resin and the surface-modified microspheres at 65° C. and 250 rpm for 1.5 h;

[0093] 4) Adding the hybrid filler to the mixture obtained in step 3), increasing the stirring speed stepwise to 1500 rpm and maintaining for 31 minutes, wherein the stepwise increase is as follows:

[0094] Stage 1: Dispersion at 600 rpm for 5 minutes;

[0095] Second stage: dispersion at 900 rpm for 8 minutes;

[0096] The third stage: dispersion at 1300 rpm for 5 minutes;

[0097] Final stage: Increase to 1480 rpm and maintain for the remaining time;

[0098] 5) Degas the mixture at a vacuum degree of -0.09 MPa for 25 min.

[0099] Example 3

[0100] See also Figure 1 The high-damping and wear-resistant coating in this embodiment comprises the following raw materials in parts by weight:

[0101] Modified polyurethane acrylate resin: 48 parts;

[0102] Core-shell microspheres: 23 parts. The core layer of the core-shell microspheres is composed of a copolymer of nitrile rubber and butyl acrylate, with the butyl acrylate content accounting for 8% of the core layer's mass. The shell layer is carboxylated polystyrene with a carboxylation degree of 15%. The core-to-shell mass ratio of the core-shell microspheres is 65:35%, and the shell thickness is 35 nm.

[0103] Hybrid filler of boron nitride nanosheets and aluminum oxide nanowires: 18 parts;

[0104] Silane coupling agent: 4.5 parts;

[0105] Defoaming agent: 0.55 parts;

[0106] The particle size of the core-shell microspheres is 200nm, and the shell contains carboxyl functional groups; the mass ratio of boron nitride nanosheets to alumina nanowires in the hybrid filler of boron nitride nanosheets and alumina nanowires is 3:1; the glass transition temperature of the modified polyurethane acrylate resin is -20°C, and the molecular chain contains a hanging chain structure.

[0107] In this embodiment, other parameters remain unchanged.

[0108] Through the examples, the results are as follows:

[0109]

[0110] The damping performance test was conducted using a DMA Q800 tester with a frequency of 1 Hz and a heating rate of 3 °C / min. The wear resistance test was conducted using a Taber 5135 abrasion tester with a CS-10 grinding wheel, a 1 kg load, and 1000 revolutions.

[0111] Specifically, damping and wear resistance are simultaneously enhanced. Through the synergistic effect of core-shell microspheres and hybrid fillers, tanδ measured at 25°C reaches 0.51-0.55, a 2.8-fold improvement compared to pure polyurethane coatings, and Taber wear is only 38-45 mg / 1000 revolutions. Corrosion resistance is also significantly improved. Salt spray testing shows that the width of scratches and rust is ≤1.5 mm after 2000 hours, and adhesion retention is 92%.

[0112] Experimental Example 1: Extreme Environment Adaptability Test

[0113] The test results are shown in the following table

[0114]

[0115]

[0116] In summary, the damping and wear resistance of the present invention are improved simultaneously. Through the synergistic effect of core-shell microspheres and hybrid fillers, it is measured at 25°C: tanδ reaches 0.51-0.55, which is 2.8 times higher than that of pure polyurethane coatings, and the Taber wear amount is only 38-45mg / 1000 revolutions. The corrosion resistance is significantly improved. The salt spray test shows that the scratch rust width is ≤1.5mm after 2000 hours, and the adhesion retention rate is 92%. The nanofillers are arranged in a directional manner, and the boron nitride nanosheets are arranged in parallel layers with a spacing of 50-80nm. Aluminum oxide nanowires are interspersed between the boron nitride sheets at an angle of 15-25° to form a three-dimensional interlocking structure, which increases the impact toughness by 40%. The core-shell microsphere-resin interface forms C=O···Si-O-Si chemical bonds. The hydroxyl density of the filler surface is increased from 12 / nm 2 Increased to 18 / nm 2 , the coating cohesion is improved and the peel strength reaches 8.2N / mm.

[0117] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0118] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. High damping and wear-resistant coating, characterized in that: The invention comprises the following raw materials in parts by weight: Modified polyurethane acrylate resin: 30-50 parts; Core-shell structure microspheres: 15-25 parts; Hybrid filler of boron nitride nanosheets and aluminum oxide nanowires: 10-20 parts; Silane coupling agent: 3-5 parts; Defoaming agent: 0.5-1 part; The particle size of the core-shell microspheres is 200-500 nm, and the shell layer contains carboxyl functional groups; the mass ratio of boron nitride nanosheets to aluminum oxide nanowires in the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is 3:

1.

2. The high damping and wear-resistant coating according to claim 1, characterized in that: The modified polyurethane acrylate resin has a glass transition temperature of -20-60° C., and contains a hanging chain structure in its molecular chain.

3. The high damping and wear-resistant coating according to claim 1, characterized in that: The core layer of the core-shell structured microspheres is composed of a copolymer of nitrile rubber and butyl acrylate, with the butyl acrylate content accounting for 8-12% of the core layer mass; the shell layer is carboxylated polystyrene with a carboxylation degree of 15-20%. The mass ratio of the core layer to the shell layer of the core-shell structured microspheres is 65:35±3%, and the shell layer thickness is 35-55nm.

4. The high damping and wear-resistant coating according to claim 1, characterized in that: The preparation method of the hybrid filler of boron nitride nanosheets and aluminum oxide nanowires is as follows: 1) mixing boron nitride nanosheets and aluminum oxide nanowires in a mass ratio of (3.2-2.8):1; 2) ultrasonic treatment in anhydrous ethanol at a power of 300-400 W for 40-50 minutes; 3) then ball milling at 200-250 rpm for 2-3 hours using a planetary ball mill; 4) The ball milling medium is zirconia beads with a diameter of 0.3-0.5 mm.

5. The high damping and wear-resistant coating according to claim 1, characterized in that: The preparation method of the modified polyurethane acrylate resin is as follows: 1) polytetrahydrofuran diol and isophorone diisocyanate are reacted in a mol ratio of 1: (2.1-2.3), 2) adding 4-6 wt% of hydroxyethyl methacrylate for end-capping, 3) Finally, dodecyl mercaptan accounting for 1.5-2% of the resin solid content is introduced as a chain transfer agent.

6. A method for producing a high-damping, wear-resistant coating, comprising the method for producing a high-damping, wear-resistant coating according to any one of claims 1 to 5, characterized in that: The manufacturing method is specifically as follows: 1) ultrasonically treating boron nitride nanosheets and aluminum oxide nanowires in an ethanol medium for 30-40 minutes, and then ball milling to obtain a hybrid filler; 2) reacting the core-shell structured microspheres with a silane coupling agent at 75-85° C. for 1.5-2 hours to obtain surface-modified microspheres; 3) mixing the modified polyurethane acrylate resin and the surface-modified microspheres at 55-65° C. and 150-250 rpm for 1-1.5 hours; 4) adding the hybrid filler to the mixture obtained in step 3), increasing the stirring speed stepwise to 1400-1500 rpm and maintaining it for 30±2 minutes; 5) Degas the mixture at a vacuum degree of -0.07 to -0.09 MPa for 15 to 25 minutes.

7. The method for producing a high-damping and wear-resistant coating according to claim 6, characterized in that: The ultrasonic treatment frequency is 38-42 kHz, and the ball milling mixing uses zirconia ball milling beads, with a ball-to-material ratio of (5-8):

1.

8. The method for producing a high-damping and wear-resistant coating according to claim 6, characterized in that: The temperature difference between step 3) and step 4) is controlled within the range of ±5°C.

9. The method for producing a high-damping and wear-resistant coating according to claim 6, wherein: The step-by-step improvement in step 4) is specifically as follows: Stage 1: Disperse at 500-600 rpm for 5 minutes; Second stage: dispersion at 800-900 rpm for 8 minutes; The third stage: dispersion at 1200-1300 rpm for 5 minutes; Final stage: Increase to 1450±50rpm and maintain for the remaining time.

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