Environment-friendly damping noise reduction coating and application thereof in automobile chassis

Abstract

The invention discloses an environment-friendly damping and noise-reducing coating and application thereof in an automobile chassis, and relates to the technical field of coatings. The preparation method comprises the following steps: activating the activity of silicon hydroxyl on the surfaces of hollow glass beads, carrying out esterification reaction with itaconic acid to introduce double bonds, grafting 3-mercaptopropyltrimethoxysilane through thiol alkene click reaction to prepare modified glass beads, and adding the modified hollow glass beads into a coating base material to prepare the environment-friendly damping noise-reducing coating. Dense silane chain segments are grafted on the surfaces of the microbeads to form silane layers, the rigidity and damping characteristics of the coating can be adjusted by introducing the silane layers, the coating has a higher loss factor under the action of dynamic stress, when the coating is coated on an automobile chassis, when the coating is vibrated or impacted, external mechanical energy can be effectively converted into heat energy, and the heat energy is effectively converted into heat energy. Therefore, the damping performance of the material is remarkably improved, the vibration and noise reduction effect is better achieved, and the protection effect is achieved. The environment-friendly damping noise-reducing coating prepared by the invention has the effects of vibration reduction and noise reduction.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and specifically to an environmentally friendly damping and noise reduction coating and its application in an automotive chassis. Background Art

[0002] During the driving of an automobile, factors such as the operation of the engine, the intrusion of wind, and the friction between the tires and the ground can cause the vibration of the vehicle body. Attaching damping materials to the parts with larger vibration amplitudes is a common method for vibration reduction and noise reduction.

[0003] In the early stage, the damping materials were mainly asphalt gaskets. Such products contain a large amount of VOCs, which cause great harm to the environment and human body and have been gradually phased out. Therefore, it is necessary to develop an environmentally friendly damping and noise reduction coating and its application in an automotive chassis.

[0004] Waterborne damping coatings generally consist of polymer emulsions, additives, fillers, etc. Polymer emulsions are the basis of damping coatings and are also the main providers of damping performance. Different additives and fillers have different effects on various properties of the coatings. Summary of the Invention

[0005] The purpose of the present invention is to provide an environmentally friendly damping and noise reduction coating and its application in an automotive chassis to solve the problems existing in the prior art.

[0006] To solve the above technical problems, the present invention provides the following technical solution: An environmentally friendly damping and noise reduction coating, which is characterized in that, by weight percentage, it comprises the following components: styrene-acrylic emulsion 15-30%, acrylate emulsion 15-30%, ME52 silicone resin emulsion 10-20%, damping filler 5-20%, modified hollow glass microspheres 5-10%, silicone additive 1-5%, wetting and dispersing agent 0.2-1%, defoaming agent 0.2-1%, thickening agent 0.2-1%, pH regulator in an appropriate amount, deionized water 25-45%;

[0007] The preparation steps of the modified hollow glass microspheres are as follows: First, activate the surface silanol activity of the hollow glass microspheres, then carry out an esterification reaction with itaconic acid to introduce double bonds, and then graft 3-mercaptopropyltrimethoxysilane through a thiol-ene click reaction.

[0008] Further, the Tg of the styrene-acrylic solution is 22°C, and the Tg of the acrylate emulsion is -8°C.

[0009] Further, the particle size of the hollow glass microspheres is 5-100 μm.

[0010] Further, the damping filler includes one or more of mica powder, heavy calcium carbonate, talc powder, and silica aerogel.

[0011] Further, a preparation method of an environment-friendly damping and noise-reducing coating includes the following preparation steps:

[0012] (1) Dissolve itaconic acid in ethanol with a mass 2 - 4 times that of itaconic acid, add activated hollow glass microspheres with a mass 1.1 - 1.3 times that of itaconic acid, stir at 300 - 400 r / min for 10 - 15 min to obtain a mixture, add p-toluenesulfonic acid with a mass 0.3 - 0.4 times that of itaconic acid, perform ultrasonic treatment at 30 - 40 kHz for 20 - 30 min, raise the temperature to 78 - 79 °C, stir at 700 - 800 r / min for 6 - 8 h, filter, and wash with deionized water to obtain hollow glass microspheres loaded with itaconic acid;

[0013] (2) Mix the hollow glass microspheres loaded with itaconic acid and 3-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.4 - 0.6 to obtain a mixture, add anhydrous ethanol with a mass 2 - 3 times that of the mixture, stir at 200 - 300 r / min for 5 - 10 min, add an initiator accounting for 1 - 3% of the mass of the mixture, stir at 250 - 300 r / min for 15 - 20 min, place it under ultraviolet light for reaction for 24 h, filter, and wash with deionized water 2 - 3 times to obtain modified hollow glass microspheres;

[0014] (3) By mass percentage, mix and stir 15 - 30% of styrene-acrylic emulsion, 15 - 30% of acrylate emulsion, 10 - 20% of ME52 silicone resin emulsion, 5 - 20% of damping filler, 5 - 10% of modified hollow glass microspheres, 1 - 5% of silicone auxiliary agent, 0.2 - 1% of wetting and dispersing agent, 0.2 - 1% of defoaming agent, 0.2 - 1% of thickening agent, an appropriate amount of pH regulator, and 25 - 45% of deionized water, and obtain an environment-friendly damping and noise-reducing coating after defoaming.

[0015] Further, the initiator in step (2) is photoinitiator 1173.

[0016] Further, the wavelength of the ultraviolet light in step (3) is 320 - 350 nm.

[0017] Further, an application of an environment-friendly damping and noise-reducing coating, which is characterized in that the environment-friendly damping and noise-reducing coating is applied to the automobile chassis. Coat the environment-friendly damping and noise-reducing coating on the washed automobile chassis, with a coating thickness of 0.5 - 0.8 mm, and dry it at 70 °C for 20 min.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0019] The present invention prepares an environment-friendly damping and noise-reducing coating by preparing modified hollow glass microspheres to achieve the effect of vibration reduction and noise reduction.

[0020] First, activate the surface silanol groups of hollow glass microspheres, then carry out an esterification reaction with itaconic acid to introduce double bonds, and then graft 3-mercaptopropyltrimethoxysilane through a thiol-ene click reaction to prepare modified glass microspheres. The modified glass microspheres are added as damping fillers to the coating base material to prepare an environmentally friendly damping and noise reduction coating; 3-mercaptopropyltrimethoxysilane and the double bond undergo a thiol-ene click reaction under ultraviolet light to graft dense silane segments on the surface of the microspheres, forming a silane layer. The introduction of the silane layer can adjust the stiffness and damping characteristics of the coating, enabling the coating to have a higher loss factor under dynamic stress. Moreover, the silane layer significantly increases the surface roughness and the density of active sites of the microspheres, and can form a more complex microstructure in the coating system, forming more covalent bonds and hydrogen bonds with the coating base material. This not only improves the dispersion performance of the hollow glass microspheres in the coating but also enhances the intermolecular force, playing the role of a reinforcing framework and improving the mechanical strength of the damping and noise reduction coating; when the coating is applied to the automotive chassis, when subjected to vibration or impact, the flexible movement of the silane segments in the silane layer will generate viscoelastic internal friction, and at the same time, the interface between the grafted microspheres and the coating matrix will also generate friction due to relative movement, causing more friction and internal energy consumption, which can effectively convert the external mechanical energy into heat energy, thereby significantly improving the damping performance of the material and better achieving the effect of vibration reduction and noise reduction, playing a protective role. Detailed implementation manners

[0021] The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] In order to more clearly illustrate the method provided by the present invention, the following examples are used for detailed description. The test methods for each index of the environmentally friendly damping and noise reduction coating prepared in the following examples are as follows:

[0023] Loss factor: The environmentally friendly damping and noise reduction coatings prepared in the examples and comparative examples with the same mass are coated on the automotive chassis with a coating thickness of 0.8 mm. After drying at 70 °C, the loss factor is tested according to GB / T 18258-2000 "Test Method for Damping Performance of Damping Materials".

[0024] Impact resistance: The environmentally friendly damping and noise reduction coatings prepared in the examples and comparative examples with the same mass are coated on the automotive chassis with a coating thickness of 0.8 mm. After drying at 70 °C, the impact resistance is tested according to GB / T 93-1987 "Standard Type of Spring Washers for Fasteners".

[0025] Water resistance: The environmentally friendly damping and noise reduction coatings prepared in the examples and comparative examples with the same mass were coated on the car chassis with a coating thickness of 0.8 mm. After drying at 70 °C, their water resistance was tested under the conditions of 20 °C for 96 h according to GB / T 1733-1993 "Method for Determining Water Resistance of Paint Films".

[0026] Oil resistance: The environmentally friendly damping and noise reduction coatings prepared in the examples and comparative examples with the same mass were coated on the car chassis with a coating thickness of 0.8 mm. After drying at 70 °C, their oil resistance was tested under the conditions of 20 °C in 120 solvent naphtha according to GB / T 1734-1993 "Method for Determining Gasoline Resistance of Paint Films".

[0027] Example 1

[0028] A preparation method of an environmentally friendly damping and noise reduction coating, comprising the following preparation steps:

[0029] (1) Add hollow glass microspheres with a particle size of 50 μm to a 10 wt% hydrochloric acid solution twice the mass of the hollow glass microspheres, stir at 200 r / min for 10 min, filter, wash with deionized water until neutral, dry at 60 °C for 30 min, and then place them in a 3 wt% sodium hydroxide solution twice the mass of the hollow glass microspheres, stir at 60 °C and 400 r / min for 30 min, filter, wash with deionized water until the pH of the washing liquid is neutral, and dry at 60 °C for 30 min to obtain activated hollow glass microspheres;

[0030] (2) Dissolve itaconic acid in ethanol twice the mass of itaconic acid, add activated hollow glass microspheres 1.1 times the mass of itaconic acid, stir at 300 r / min for 10 min to obtain a mixture, add p-toluenesulfonic acid 0.3 times the mass of itaconic acid, ultrasonicate at 30 kHz for 20 min, raise the temperature to 78 °C, stir at 700 r / min for 6 h, filter, and wash with deionized water 3 times to obtain hollow glass microspheres loaded with itaconic acid;

[0031] (3) Mix the hollow glass microspheres loaded with itaconic acid and 3-mercaptopropyltrimethoxysilane at a mass ratio of 1:0.4 to obtain a mixture, add anhydrous ethanol twice the mass of the mixture, stir at 200 r / min for 5 min, add 2% photoinitiator 1173 of the mass of the mixture, stir at 250 r / min for 15 min, place it under ultraviolet light with a wavelength of 320 nm and react for 24 h, filter, and wash with deionized water 2 times to obtain modified hollow glass microspheres;

[0032] (4) By mass percentage, mix 15% styrene-acrylic emulsion, 15% acrylate emulsion, 10% ME52 silicone resin emulsion, 5% mica powder with a particle size of 50um, 5% heavy calcium carbonate, 5% aerogel silica, 5% modified hollow glass microspheres, 2% IOTA9086 silicone buffer energy-absorbing material, 0.3% 731A wetting dispersant, 0.3% NXZ defoamer, 0.4% Tesfu DR72 thickener, and 37% deionized water. Add AMP-95 pH regulator to adjust the pH to 8, stir, and defoam to obtain an environmentally friendly damping and noise reduction coating. The silica aerogel is sourced from Shanghai Shichang New Materials Co., Ltd. with the model SC-SiO2.

[0033] Example 2

[0034] A preparation method of an environmentally friendly damping and noise reduction coating includes the following preparation steps:

[0035] (1) Add hollow glass microspheres with a particle size of 50μm to a 20wt% hydrochloric acid solution that is 2 times the mass of the hollow glass microspheres. Stir at 250r / min for 15min, filter, wash with deionized water until neutral, dry at 60°C for 30min, then place in a 5wt% sodium hydroxide solution that is 2 times the mass of the hollow glass microspheres. Stir at 70°C and 450r / min for 40min, filter, wash with deionized water until the pH of the washing liquid is neutral, and dry at 60°C for 30min to obtain activated hollow glass microspheres;

[0036] (2) Dissolve itaconic acid in ethanol that is 3 times the mass of itaconic acid. Add activated hollow glass microspheres that are 1.2 times the mass of itaconic acid, stir at 350r / min for 13min to obtain a mixture. Add p-toluenesulfonic acid that is 0.3 times the mass of itaconic acid, ultrasonicate at 35kHz for 25min, heat up to 78°C, stir at 750r / min for 7h, filter, and wash with deionized water 3 times to obtain hollow glass microspheres loaded with itaconic acid;

[0037] (3) Mix the hollow glass microspheres loaded with itaconic acid and 3-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.5 to obtain a mixture. Add anhydrous ethanol that is 3 times the mass of the mixture, stir at 250r / min for 8min, add 2% photoinitiator 1173 based on the mass of the mixture, stir at 300r / min for 20min, place it under ultraviolet light with a wavelength of 340nm and react for 24h, filter, and wash with deionized water 3 times to obtain modified hollow glass microspheres;

[0038] (4) By mass percentage, mix 20% styrene-acrylic emulsion, 15% acrylate emulsion, 13% ME52 silicone resin emulsion, 5% mica powder with a particle size of 50um, 5% heavy calcium carbonate, 5% aerogel silica, 7% modified hollow glass microspheres, 3% IOTA9086 silicone buffer energy-absorbing material, 0.3% 731A wetting dispersant, 0.5% NXZ defoamer, 0.5% Tesfu DR72 thickener, and 25.7% deionized water. Add AMP-95 pH regulator to adjust the pH to 9, stir, and defoam to obtain an environmentally friendly damping and noise-reducing coating. The silica aerogel is sourced from Shanghai Shichang New Materials Co., Ltd. and has a model of SC-SiO2.

[0039] Example 3

[0040] A preparation method of an environmentally friendly damping and noise-reducing coating includes the following preparation steps:

[0041] (1) Add hollow glass microspheres with a particle size of 50μm to a 30wt% hydrochloric acid solution that is 3 times the mass of the hollow glass microspheres. Stir at 300r / min for 15min, filter, wash with deionized water until neutral, dry at 60°C for 30min, then place in a 7wt% sodium hydroxide solution that is 3 times the mass of the hollow glass microspheres. Stir at 80°C and 500r / min for 45min, filter, wash with deionized water until the pH of the washing liquid is neutral, and dry at 60°C for 30min to obtain activated hollow glass microspheres;

[0042] (2) Dissolve itaconic acid in ethanol that is 4 times the mass of the itaconic acid. Add activated hollow glass microspheres that are 1.3 times the mass of the itaconic acid. Stir at 400r / min for 15min to obtain a mixture. Add p-toluenesulfonic acid that is 0.4 times the mass of the itaconic acid, ultrasonicate at 40kHz for 30min, raise the temperature to 79°C, stir at 800r / min for 8h, filter, and wash with deionized water 3 times to obtain hollow glass microspheres loaded with itaconic acid;

[0043] (3) Mix the hollow glass microspheres loaded with itaconic acid and 3-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.6 to obtain a mixture. Add anhydrous ethanol that is 3 times the mass of the mixture. Stir at 300r / min for 10min, add 3% photoinitiator 1173 based on the mass of the mixture, stir at 300r / min for 20min, place it under ultraviolet light with a wavelength of 350nm and react for 24h, filter, and wash with deionized water 3 times to obtain modified hollow glass microspheres;

[0044] (4) By mass percentage, mix 16% styrene-acrylic emulsion, 16% acrylate emulsion, 10% ME52 silicone resin emulsion, 5% mica powder with a particle size of 50um, 6% heavy calcium carbonate, 5% aerogel silica, 8% modified hollow glass microspheres, 2% IOTA9086 silicone buffer energy-absorbing material, 0.5% 731A wetting and dispersing agent, 0.5% NXZ defoamer, 0.2% Tesfu DR72 thickener, and 30.8% deionized water. Add AMP-95 pH regulator to adjust the pH to 8 - 10, stir, and defoam to obtain an environmentally friendly damping and noise-reducing coating. The silica aerogel is sourced from Shanghai Shichang New Materials Co., Ltd., with the model SC-SiO2.

[0045] Comparative Example 1

[0046] The difference between Comparative Example 1 and Example 2 is that step (1) is absent, and the activated hollow glass microspheres in step (2) are changed to hollow glass microspheres; the remaining steps are the same as in Example 2.

[0047] Comparative Example 2

[0048] The difference between Comparative Example 2 and Example 2 is that step (2) is absent, and the hollow glass microspheres loaded with itaconic acid in step (3) are changed to activated hollow glass microspheres; the remaining steps are the same as in Example 2.

[0049] Comparative Example 3

[0050] The difference between Comparative Example 3 and Example 2 lies in step (3). The modified hollow glass microspheres in step (4) are changed to hollow glass microspheres loaded with itaconic acid; the remaining steps are the same as in Example 2.

[0051] Effect Example

[0052] The following Table 1 presents the performance analysis results of the environmentally friendly damping and noise-reducing coatings of Examples 1 to 3 and Comparative Examples 1 to 3 of the present invention.

[0053] Table 1

[0054]

[0055] From the comparison of the experimental data of Example 2 and Comparative Examples 1-3, it can be found that in the present invention, the surface silanol groups of hollow glass microspheres are first activated, and then an esterification reaction occurs with itaconic acid to introduce double bonds. Then, 3-mercaptopropyltrimethoxysilane is grafted through a thiol-ene click reaction to prepare modified glass microspheres. The modified glass microspheres are added as a damping filler to the coating base material to prepare an environmentally friendly damping and noise reduction coating; the 3-mercaptopropyltrimethoxysilane and the double bond undergo a thiol-ene click reaction under ultraviolet light to graft dense silane segments on the surface of the microspheres, forming a silane layer. The introduction of the silane layer can adjust the stiffness and damping characteristics of the coating, making the coating have a higher loss factor under dynamic stress. Moreover, the silane layer significantly increases the surface roughness and the density of active sites of the microspheres, and can form a more complex microstructure in the coating system, forming more covalent bonds and hydrogen bonds with the coating base material. This not only improves the dispersion performance of the hollow glass microspheres in the coating, but also enhances the intermolecular force, playing the role of an enhanced skeleton and improving the mechanical strength of the damping and noise reduction coating; when the coating is applied to the automotive chassis, when subjected to vibration or impact, the flexible movement of the silane segments in the silane layer will generate viscoelastic internal friction. At the same time, the interface between the grafted microspheres and the coating matrix will also generate friction due to relative movement, resulting in more friction and internal energy consumption, which can effectively convert the external mechanical energy into heat energy, thereby significantly improving the damping performance of the material and better achieving the effect of vibration reduction and noise reduction, playing a protective role.

[0056] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed claim.

Claims

1. An environmentally friendly damping and noise reduction coating, characterized in that, By weight percentage, it comprises the following components: styrene-acrylic emulsion 15-30%, acrylate emulsion 15-30%, silicone resin emulsion 10-20%, damping filler 5-20%, modified hollow glass microspheres 5-10%, silicone auxiliary 1-5%, wetting and dispersing agent 0.2-1%, defoaming agent 0.2-1%, thickening agent 0.2-1%, pH regulator in an appropriate amount, deionized water 25-45%; The preparation steps of the modified hollow glass microspheres are as follows: first activate the surface silanol activity of the hollow glass microspheres, then carry out an esterification reaction with itaconic acid to introduce double bonds, and then graft 3-mercaptopropyltrimethoxysilane through a thiol-ene click reaction to obtain.

2. The environmentally friendly damping and noise reduction coating according to claim 1, wherein The Tg of the styrene-acrylic solution is 22 °C, and the Tg of the acrylate emulsion is -8 °C.

3. An environmentally friendly damping and noise reduction coating according to claim 1, characterized in that, The particle size of the hollow glass microspheres is 5-100 μm.

4. An environment-friendly damping and noise-reducing coating according to claim 3, characterized in that, The damping filler includes one or several of mica powder, heavy calcium carbonate, talc powder, and silica aerogel.

5. A preparation method of an environment-friendly damping and noise-reducing coating, characterized in that, It includes the following preparation steps: (1) Dissolve itaconic acid in ethanol with a mass 2-4 times that of itaconic acid, add activated hollow glass microspheres with a mass 1.1-1.3 times that of itaconic acid, stir at 300-400 r / min for 10-15 min to obtain a mixture, add p-toluenesulfonic acid with a mass 0.3-0.4 times that of itaconic acid, ultrasonicate at 30-40 kHz for 20-30 min, heat up to 78-79 °C, stir at 700-800 r / min for 6-8 h, filter, and wash with deionized water to obtain hollow glass microspheres loaded with itaconic acid; (2) Mix the hollow glass microspheres loaded with itaconic acid and 3-mercaptopropyltrimethoxysilane at a mass ratio of 1:0.4-0.6 to obtain a mixture, add anhydrous ethanol with a mass 2-3 times that of the mixture, stir at 200-300 r / min for 5-10 min, add an initiator with a mass 1-3% of the mixture, stir at 250-300 r / min for 15-20 min, place it under ultraviolet light for reaction for 24 h, filter, and wash with deionized water 2-3 times to obtain modified hollow glass microspheres; (3) By weight percentage, mix and stir 15-30% of styrene-acrylic emulsion, 15-30% of acrylate emulsion, 10-20% of silicone resin emulsion, 5-20% of damping filler, 5-10% of modified hollow glass microspheres, 1-5% of silicone auxiliary, 0.2-1% of wetting and dispersing agent, 0.2-1% of defoaming agent, 0.2-1% of thickening agent, pH regulator in an appropriate amount, and 25-45% of deionized water, and obtain an environmentally friendly damping and noise reduction coating after defoaming.

6. The preparation method of an environment-friendly damping and noise-reducing coating according to claim 5, characterized in that, The initiator in step (2) is photoinitiator 1173.

7. The preparation method of an environment-friendly damping and noise-reducing coating according to claim 5, characterized in that, The wavelength of the ultraviolet light in step (3) is 320-350 nm.

8. Application of an environment-friendly damping and noise-reducing coating, characterized in that, The environmentally friendly damping and noise reduction coating is applied to the car chassis. Coat the environmentally friendly damping and noise reduction coating on the washed car chassis, with a coating thickness of 0.5-0.8 mm, and dry it at 70 °C for 20 min.

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