Water-based polymer composite sound-absorbing and sound-insulating coating and preparation method thereof

Abstract

The invention belongs to the technical field of high-molecular polymers and functional coatings, and particularly relates to a water-based high-molecular composite sound-absorbing and sound-insulating coating and a preparation method thereof. The composite sound-absorbing and sound-insulating coating comprises the following components in parts by weight: 20-40 parts of silicone acrylic emulsion; 15-30 parts of a porous sound-absorbing filler; 20-40 parts of a high-density sound insulation filler; 5 to 10 parts of cross-linked acrylate coated butyl rubber core-shell emulsion; 1-8 parts of a functional auxiliary agent; and 10 to 25 parts of deionized water. Through cooperative use of the porous sound-absorbing filler, the high-density sound-insulating filler and the butyl rubber elastic damping material, the sound-absorbing coefficient and the sound-insulating amount of the coating can be synergistically improved. Core-shell coating treatment is carried out on butyl rubber through cross-linked acrylate, the adhesive force, flexibility and alkali resistance of the coating can be remarkably improved, and meanwhile the acoustic performance of the coating is also improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high molecular polymers and functional coatings, and particularly relates to a water-based high molecular composite sound-absorbing and sound-insulating coating and a preparation method thereof. BACKGROUND

[0002] With the acceleration of urbanization, the expansion of industrial production and the growth of traffic flow, noise pollution (such as indoor noise of buildings, traffic noise, noise of industrial equipment, etc.) has become an important problem affecting the living environment and production efficiency. According to statistics, the compliance rate of urban environmental noise in China is less than 70%, and low-frequency noise (such as elevators, air conditioner outdoor units, and traffic low-frequency vibrations) has a particularly significant impact on human health (such as sleep disorders and cardiovascular diseases) due to its long transmission distance and slow attenuation, prompting the urgent need for efficient and convenient noise reduction materials.

[0003] Traditional noise reduction materials are mainly divided into sound-absorbing materials (such as glass wool, rock wool, and porous foam) and sound-insulating materials (such as sound-insulating boards, metal plates, and sealing strips), but they have significant drawbacks:

[0004] Sound-absorbing materials: rely on porous structures to convert sound energy into heat energy through air viscous resistance and friction, and have good absorption effect on medium and high frequency sound waves (>1000Hz), but have weak low-frequency sound absorption ability (low-frequency waves have long wavelengths, and materials need to have large thickness or resonance structures), and have problems such as complex installation (need to be fixed with keels), large space occupation (thickness usually >50mm), easy dust generation (such as glass wool), and poor environmental protection (some contain formaldehyde).

[0005] Sound-insulating materials: based on the "mass law" (the larger the surface density, the better the sound insulation effect), such as concrete walls and lead plates, which can block sound waves, but have large weight (such as a 100mm concrete wall weighs about 240kg / m 2 ), high construction difficulty (need to be cast in place or spliced), poor flexibility (difficult to adapt to curved / irregular substrates), and cannot absorb sound waves (easy to cause sound reflection and secondary noise).

[0006] Sound-absorbing and sound-insulating coatings are a kind of composite material composed of sound-insulating materials, sound-absorbing materials, and high molecular polymers. As a lightweight and convenient alternative to traditional noise reduction materials, sound-absorbing and sound-insulating coatings have broad application prospects due to their strong adaptability and small space occupation. Although sound-absorbing and sound-insulating coatings solve some of the problems of traditional materials, their technical maturity is still low, and existing products still have significant shortcomings in terms of acoustic performance (sound absorption and sound insulation are difficult to balance), physical and mechanical properties (weak adhesion, insufficient flexibility, poor water resistance; cracks may occur due to thermal expansion and cold contraction of the substrate, and bubbling and peeling may occur on wet substrates, losing sound insulation and sealing), construction efficiency (need to set up multiple layers and multiple coatings, and the construction is complex), and cost control (some products use nano-porous materials such as aerogels, which have high cost). SUMMARY

[0007] In view of the above-mentioned defects and shortcomings of the prior art, the primary object of the present application is to provide a water-based high polymer composite sound-absorbing and sound-insulating coating.

[0008] Another object of the present application is to provide a preparation method of the water-based high polymer composite sound-absorbing and sound-insulating coating.

[0009] The object of the present application is achieved by the following technical solutions.

[0010] A water-based high polymer composite sound-absorbing and sound-insulating coating comprises the following components by weight:

[0011] 20-40 parts of a silicone-acrylate emulsion;

[0012] 15-30 parts of a porous sound-absorbing filler;

[0013] 20-40 parts of a high-density sound-insulating filler;

[0014] 5-10 parts of a cross-linked acrylate-coated butyl rubber core-shell emulsion;

[0015] 1-8 parts of a functional additive;

[0016] 10-25 parts of deionized water.

[0017] Preferably, the silicone-acrylate emulsion is prepared by the following method:

[0018] An emulsifier is added to a reaction kettle containing deionized water and heated, stirred and dissolved, and then acrylate monomers, acrylic monomers and silane coupling agent monomers are mixed and emulsified to obtain a monomer emulsion; then an initiator solution is added dropwise and incubated for copolymerization to obtain the silicone-acrylate emulsion.

[0019] Preferably, in the preparation of the silicone-acrylate emulsion, the emulsifier is one or more of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate and nonylphenol polyoxyethylene ether; and the amount of the emulsifier added is 3-6% of the mass of the deionized water.

[0020] Preferably, in the preparation of the silicone-acrylate emulsion, the temperature of the heating, stirring and dissolving and the incubation for copolymerization is 60-80℃.

[0021] Preferably, in the preparation of the silicone-acrylate emulsion, the acrylate monomers are one or more of methyl methacrylate, ethyl acrylate and butyl acrylate; and the amount of the acrylate monomers added is 40-60% of the mass of the acrylic monomers.

[0022] The main role of the acrylate monomers is to coordinate the hardness and flexibility of the coating film and improve the water resistance.

[0023] Preferably, in the preparation of the above-mentioned silicone-acrylate emulsion, the acrylate monomer is one or both of acrylic acid and methacrylic acid.

[0024] The main role of the acrylate monomer in the present application is to improve the adhesion of the coating.

[0025] Preferably, in the preparation of the above-mentioned silicone-acrylate emulsion, the silane coupling agent monomer is one or both of methacryloxypropyltrimethoxysilane and vinyltriethoxysilane; the amount of the silane coupling agent monomer added is 10-20% of the mass of the acrylate monomer.

[0026] The main role of the silane coupling agent monomer in the present application is to improve the interfacial bonding with the sound-absorbing and sound-insulating filler through the hydrolyzed silicon hydroxyl group, thereby avoiding cracking of the coating or falling off of the filler; and to improve the water resistance and strength performance of the coating through the micro-crosslinking of the hydrolyzed silicon hydroxyl group.

[0027] Preferably, in the preparation of the above-mentioned silicone-acrylate emulsion, the solid content of the monomer emulsion is 40-60%.

[0028] Preferably, in the preparation of the above-mentioned silicone-acrylate emulsion, the initiator is potassium persulfate or ammonium persulfate; the total amount of the initiator added is 0.3-0.6% of the mass of the monomer emulsion.

[0029] Preferably, the porous sound-absorbing filler is one or several of expanded perlite, hollow glass microbeads, and porous ceramic powder with a particle size of 0.005-0.5 mm.

[0030] Preferably, the high-density sound-insulating filler is one or several of barite powder (BaSO4), ferrite powder (Fe3O4), and calcium carbonate powder (CaCO3) with a particle size of 1-10 μm.

[0031] Preferably, the mass ratio of the porous sound-absorbing filler to the high-density sound-insulating filler is controlled to be 1:1-2. Under the above-mentioned ratio range, the sound-absorbing effect of the porous structure is ensured, and the areal density (dry film density ≥ 1.2 g / cm 3 ) is increased through the high-density filler, thereby enhancing the sound-insulating performance.

[0032] Preferably, the cross-linked acrylate-coated butyl rubber core-shell emulsion is prepared by the following method:

[0033] (1) Acrylate monomer and diene cross-linking agent are added to an aqueous emulsifier solution for mixing and emulsification to obtain a shell monomer pre-emulsion;

[0034] (2) The shell monomer pre-emulsion obtained in step (1) is added to butyl rubber latex for stirring and mixing and emulsification, then an initiator solution is added dropwise for polymerization under heating to obtain a cross-linked acrylate-coated butyl rubber core-shell emulsion.

[0035] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the acrylate monomer is a mixture of methyl methacrylate and butyl acrylate in a mass ratio of 1:1-2; the diene cross-linking agent is one or more of isoprene, 1,4-pentadiene, 1,5-hexadiene, and 2,5-dimethyl-1,5-hexadiene.

[0036] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the diene cross-linking agent is added in an amount of 0.5-3% of the mass of the acrylate monomer.

[0037] The acrylate monomer and diene cross-linking agent used in the present application have good affinity with butyl latex particles, and can better coat the butyl latex particles after emulsification, and then cross-link into a shell through in-situ polymerization to obtain a cross-linked acrylate coated butyl rubber core-shell emulsion with good coating effect. The acrylate coating can significantly improve the compatibility of butyl rubber particles with silicone-acrylate adhesive resin, which is conducive to forming an "island structure" in the dried coating film in which butyl rubber particles are dispersed in silicone-acrylate film-forming resin, reducing the continuous phase separation of butyl rubber, thereby significantly improving the dispersion effect of butyl rubber and reducing the influence on the overall uniformity of the coating film. The obtained composite coating has better damping performance and flexibility, and can achieve better sound absorption and sound insulation effects and stronger adhesion.

[0038] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the aqueous emulsifier solution is an aqueous solution of at least one emulsifier selected from the group consisting of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, and nonylphenol polyoxyethylene ether; and the mass concentration of the aqueous emulsifier solution is 2-5%.

[0039] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the solid content of the shell monomer pre-emulsion is 40-60%; the solid content of the butyl latex is 40-50%; and the addition amount of the shell monomer pre-emulsion is 30-50% of the mass of the butyl latex.

[0040] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the initiator is potassium persulfate or ammonium persulfate, and the total amount of the initiator added is 0.5-1.0% of the mass of the shell monomer pre-emulsion.

[0041] Preferably, in the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the temperature of the heating polymerization reaction is 60-80℃.

[0042] Preferably, the functional auxiliary agent includes at least one of a dispersing agent (such as sodium polyacrylate), a defoaming agent (such as silicone), a thickening agent (such as hydroxyethyl cellulose), a film-forming auxiliary agent (such as alcohol ester twelve), and a mildew-proof agent (such as isothiazolinone).

[0043] The preparation method of the above-mentioned water-based polymer composite sound-absorbing and sound-insulating coating comprises the following preparation steps:

[0044] The dispersant and the defoaming agent are added into the deionized water and stirred and uniformly mixed, then the porous sound-absorbing filler and the high-density sound-insulating filler are added and stirred and ground, then the silicone-acrylate emulsion and the cross-linked acrylate coated butyl rubber core-shell emulsion are added and uniformly mixed, finally, the film-forming aid and the thickening agent are added to adjust the viscosity to 8000-12000 mPa·s, filtration and packaging are performed, and thus the water-based polymer composite sound-absorbing and sound-insulating coating is obtained.

[0045] The functions and principles of the components of the present application are as follows:

[0046] The silicone-acrylate emulsion is a film-forming material, which provides the mechanical properties and adhesion of the coating, is environmentally friendly, has good film-forming properties and strong compatibility with the filler.

[0047] The cross-linked acrylate coated butyl rubber core-shell emulsion introduces damping properties, consumes vibration energy through internal friction and enhances the low-frequency sound-insulating effect.

[0048] The porous sound-absorbing filler has a porous structure, enhances sound energy reflection and scattering, consumes sound energy through air viscous resistance and heat conduction (mainly high-frequency sound absorption) and has excellent sound-absorbing performance.

[0049] The high-density sound-insulating filler is a high-density inorganic filler, which blocks the transmission of sound waves through the law of mass (mainly middle and low-frequency sound insulation).

[0050] The functional aid adjusts the workability, stability and durability of the coating. For example, the dispersant prevents the agglomeration of the filler and improves the uniformity of dispersion; the defoaming agent eliminates the bubbles generated during preparation and application, avoiding the influence of pinholes in the coating on the acoustic properties; the thickening agent adjusts the viscosity to 8000-12000 mPa·s (25℃, Brookfield viscometer), which is suitable for spray / roll coating application; and the film-forming aid reduces the minimum film-forming temperature (MFT) of the resin, ensuring the integrity of low-temperature film formation.

[0051] The sound-absorbing mechanism relies on the connected porous structure inside the coating (such as the pore size of 10-20 μm of the porous sound-absorbing filler), and after the sound wave enters the pore, the sound energy is converted into heat energy through the viscous friction of air molecules and the pore wall and the vibration loss of the material skeleton.

[0052] The sound-insulating mechanism increases the area density of the coating through the high-density sound-insulating filler, and inhibits the vibration of the substrate through the damping aid (such as butyl rubber), thereby reducing the transmission of sound waves.

[0053] Through the synergistic effect of the above-mentioned components, a three-dimensional porous structure and a damping vibration reduction system are formed inside the coating, which can simultaneously realize the dual effects of sound absorption and sound insulation.

[0054] Compared with the prior art, the present application has the following advantages:

[0055] (1) By compounding "porous light sound-absorbing filler" with "high-density sound-insulating filler", high-frequency sound absorption and low-frequency sound insulation are considered, and the defects of traditional coatings "single function of sound absorption or sound insulation" are solved. Butyl rubber elastic damping material is introduced, and the butyl rubber viscoelasticity is used to consume vibration energy through internal friction, thereby further improving the low-frequency sound insulation volume. The acoustic performance is realized through the synergistic effect of "porous sound absorption + high-density sound insulation + damping energy consumption".

[0056] (2) By using acrylate shell crosslinking coating treatment on butyl rubber, the dispersion performance of butyl rubber in silicone propylene film-forming resin is improved, the sound absorption and sound insulation effect is improved, and the influence on adhesion is reduced.

[0057] (3) The composite coating of the present application uses water as the solvent, has low VOC content, and has no irritating odor during construction, meeting the requirements of green building. DETAILED DESCRIPTION

[0058] The present application will be further described in detail below in combination with examples, but the embodiments of the present application are not limited thereto.

[0059] Example 1

[0060] A water-based high molecular composite sound-absorbing and sound-insulating coating, comprising the following components by weight parts:

[0061] Base material: silicone propylene emulsion 40 parts; crosslinked acrylate coated butyl rubber core-shell emulsion 5 parts.

[0062] Composite porous sound-absorbing filler: expanded perlite (particle size 0.1-0.5mm) 12 parts; hollow glass microbeads (particle size 5-20μm) 8 parts.

[0063] Composite high-density sound-insulating filler: barite powder (BaSO4, particle size 5-10μm) 20 parts; ferrite powder (Fe3O4, particle size 1-5μm) 10 parts.

[0064] Functional additives: dispersant (sodium polycarboxylate) 1.0 part; defoaming agent (silicone type) 0.5 part; thickening agent (hydroxyethyl cellulose) 0.8 part; film-forming aid (dodecanol ester) 3.0 part; preservative (isothiazolinone) 0.3 part.

[0065] Deionized water 19.4 parts.

[0066] The silicone propylene emulsion is prepared by the following method:

[0067] The emulsifiers sodium dodecyl benzene sulfonate and nonylphenol polyoxyethylene ether are added into a reaction kettle containing deionized water in a mass ratio of 1:1, heated to 60℃ and stirred to dissolve, the total mass concentration of the emulsifiers is 4%, then methyl methacrylate, butyl acrylate, acrylic acid and methacryloyloxypropyl trimethoxysilane are mixed and emulsified in a mass ratio of 30:20:100:15 to obtain a monomer emulsion with a solid content of 50%; then the temperature is raised to 70℃ and ammonium persulfate initiator solution is added dropwise for reaction, the total amount of ammonium persulfate added is 0.5% of the mass of the monomer emulsion, the dropwise adding time is controlled to be 1.5h, and after the dropwise adding is completed, the reaction is continued for 3h to obtain a silicone-acrylate emulsion.

[0068] The cross-linked acrylate coated butyl rubber core-shell emulsion is prepared by the following method:

[0069] (1) The cross-linking agent of methyl methacrylate, butyl acrylate and isoprene is added to the mixed emulsifier aqueous solution of sodium dodecyl sulfonate and nonylphenol polyoxyethylene ether (SDS:NPEO=2:1, the total mass concentration of the emulsifier is 3%) in a mass ratio of 40:60:2, mixed and emulsified to obtain a shell monomer pre-emulsion with a solid content of 50%.

[0070] (2) The shell monomer pre-emulsion obtained in step (1) is added to the butyl latex (purchased, solid content of 45%) in a mass ratio of 40:100, stirred and mixed and emulsified, then heated to 70℃ and ammonium persulfate initiator solution is added dropwise for polymerization reaction, the total amount of ammonium persulfate added is 0.8% of the mass of the shell monomer pre-emulsion, the dropwise adding time is controlled to be 1h, and after the dropwise adding is completed, the reaction is continued for 4h to obtain a cross-linked acrylate coated butyl rubber core-shell emulsion.

[0071] The preparation method of the water-based high molecular composite sound-absorbing and sound-insulating coating of the embodiment comprises the following preparation steps:

[0072] S1. Pre-mixing stage: deionized water (19.4 parts) is added to a dispersion kettle, stirring is started (speed 500 rpm), and a dispersing agent (1.0 part) and a defoaming agent (0.5 part) are sequentially added and stirred for 5 min until completely dissolved.

[0073] S2. Filler dispersion stage: the stirring speed is kept at 1200 rpm, and expanded perlite (12 parts), hollow glass microbeads (8 parts), barite powder (20 parts) and ferrite powder (10 parts) are sequentially and slowly added, and after each addition, the fillers are dispersed for 10 min, and the total dispersion time is 40 min.

[0074] S3. Base mixed with additives stage: reduce the rotation speed to 400 rpm, add silicone-acrylate emulsion (40 parts), crosslinking acrylate coated butyl rubber core-shell emulsion (5 parts), stir for 15 min; then add film forming additives (3.0 parts), thickening agent (0.8 parts), preservative (0.3 parts) in sequence, stir for 20 min until the system is uniform.

[0075] S4. Filtration and adjustment: filter with 100 mesh filter screen to remove agglomerated particles; detect viscosity, if deviates from the target (8000-12000 mPa·s), fine-tune by adding thickening agent or deionized water, and the water-based high polymer composite sound-absorbing and sound-insulating coating is obtained.

[0076] The sound-absorbing and sound-insulating coating obtained in this example has an average sound absorption coefficient (GB / T 18696.2-2002) of 0.65 (125-4000 Hz), a sound absorption coefficient of >0.7 in the frequency band of 500-2000 Hz, and a peak value (1000 Hz) of 0.82. The weighted sound insulation volume (Rw) (GB / T 50121-2005, dry film thickness of 2 mm) is 34 dB (100-3000 Hz). The VOC content is ≤80 g / L (GB 18582-2020). The adhesion (GB / T 9286-2021 grid method) is 0 level. The water resistance (GB / T 1733-1993, immersion for 24 h) has no blistering or peeling. The alkali resistance (GB / T 9265-2009, saturated Ca(OH)2, 24 h) is normal. The flexibility (GB / T 1731-2020, bending test) result is 2 mm (the coating has no cracks).

[0077] Example 2

[0078] A water-based high polymer composite sound-absorbing and sound-insulating coating, comprising the following components by weight parts:

[0079] Base: silicone-acrylate emulsion (same as in Example 1) 30 parts; crosslinking acrylate coated butyl rubber core-shell emulsion (same as in Example 1) 7.5 parts.

[0080] Porous sound-absorbing filler: expanded perlite (particle size 0.1-0.5 mm) 15 parts.

[0081] High-density sound-insulating filler: barite powder (BaSO4, particle size 5-10 μm) 20 parts.

[0082] Functional additives: dispersant (sodium polycarboxylate) 0.8 parts; defoamer (silicone-based) 0.5 parts; thickening agent (hydroxyethyl cellulose) 1.5 parts; film forming additive (dodecanol ester) 2.0 parts; preservative (isothiazolinone) 0.2 parts.

[0083] Deionized water 22.5 parts.

[0084] The preparation method of the water-based polymer composite sound-absorbing and sound-insulating coating of the present example is the same as that of Example 1.

[0085] The sound-absorbing and sound-insulating coating obtained in the present example is tested to have an average sound absorption coefficient of 0.58 (125-4000 Hz), a sound absorption coefficient > 0.6 in the frequency band of 500-2000 Hz, and a peak value (1200 Hz) of 0.76. The weighted sound insulation volume (Rw) is 30 dB (100-3000 Hz). The VOC content is ≤ 80 g / L. The adhesion is 0 level. The water resistance test shows no blistering and no peeling. The alkali resistance test shows no abnormality. The flexibility test result is 1 mm (the coating has no cracks).

[0086] Example 3

[0087] A water-based polymer composite sound-absorbing and sound-insulating coating, comprising the following components by weight:

[0088] Base material: 20 parts of silicone-acrylate emulsion (the same as in Example 1); 10 parts of cross-linked acrylate-coated butyl rubber core-shell emulsion (the same as in Example 1).

[0089] Porous sound-absorbing filler: 30 parts of expanded perlite (particle size 0.1-0.5 mm).

[0090] High-density sound-insulating filler: 40 parts of barite powder (BaSO4, particle size 5-10 μm).

[0091] Functional additives: 1.6 parts of dispersant (sodium salt of polycarboxylic acid); 0.4 parts of defoaming agent (silicone-based); 0.3 parts of thickening agent (hydroxyethyl cellulose); 4.0 parts of film-forming aid (dodecanol ester); 0.2 parts of preservative (isothiazolinone).

[0092] Deionized water: 13.5 parts.

[0093] The preparation method of the water-based polymer composite sound-absorbing and sound-insulating coating of the present example is the same as that of Example 1.

[0094] The sound-absorbing and sound-insulating coating obtained in the present example is tested to have an average sound absorption coefficient of 0.68 (125-4000 Hz), a sound absorption coefficient > 0.7 in the frequency band of 500-2000 Hz, and a peak value (900 Hz) of 0.85. The weighted sound insulation volume (Rw) is 37 dB (100-3000 Hz). The VOC content is ≤ 80 g / L. The adhesion is 1 level. The water resistance test shows no blistering and no peeling. The alkali resistance test shows no abnormality. The flexibility test result is 3 mm (the coating has no cracks).

[0095] Example 4

[0096] A water-based polymer composite sound-absorbing and sound-insulating coating, which is different from Example 1 in that the cross-linked acrylate-coated butyl rubber core-shell emulsion is prepared by the following method:

[0097] (1) Methyl methacrylate, butyl acrylate and 1,4-pentadiene crosslinking agent with a mass ratio of 50:50:0.5 were added to a mixed emulsifier aqueous solution of sodium dodecyl sulfonate and nonylphenol polyoxyethylene ether (SDS:NPEO = 2:1, total mass concentration of emulsifier was 3%) to mix and emulsify, to obtain a shell monomer pre-emulsion with a solid content of 50%.

[0098] (2) The shell monomer pre-emulsion obtained in step (1) was added to butyl latex (purchased, solid content was 45%) with a mass ratio of 50:100 to mix and emulsify by stirring, then heated to 70°C to add ammonium persulfate initiator solution dropwise to stir and polymerize, the total amount of ammonium persulfate added was 0.8% of the mass of the shell monomer pre-emulsion, the dropwise adding time was controlled to be 1 h, after the dropwise adding was completed, the reaction was continued for 4 h, to obtain a crosslinked acrylate coated butyl rubber core-shell emulsion.

[0099] The sound absorption and insulation coating obtained in the example was tested, the average value of the sound absorption coefficient (GB / T 18696.2-2002) was 0.63 (125-4000 Hz), the sound absorption coefficient in the frequency band of 500-2000 Hz was >0.7, the peak value (1000 Hz) reached 0.81. The weighted sound insulation volume (Rw) was 32 dB (100-3000 Hz). The VOC content was ≤80 g / L. The adhesion was level 1. The water resistance test showed no blistering and no peeling. The alkali resistance test showed no abnormality. The flexibility test result was 2 mm (the coating had no cracks).

[0100] Example 5

[0101] A water-based high molecular composite sound absorption and insulation coating, compared with example 1, the difference is that the crosslinked acrylate coated butyl rubber core-shell emulsion is prepared by the following method:

[0102] (1) Methyl methacrylate, butyl acrylate and 2,5-dimethyl-1,5-hexadiene crosslinking agent with a mass ratio of 33.3:66.6:3 were added to a mixed emulsifier aqueous solution of sodium dodecyl sulfonate and nonylphenol polyoxyethylene ether (SDS:NPEO = 2:1, total mass concentration of emulsifier was 3%) to mix and emulsify, to obtain a shell monomer pre-emulsion with a solid content of 50%.

[0103] (2) The shell monomer pre-emulsion obtained in step (1) was added to butyl latex (purchased, solid content was 45%) with a mass ratio of 30:100 to mix and emulsify by stirring, then heated to 70°C to add ammonium persulfate initiator solution dropwise to stir and polymerize, the total amount of ammonium persulfate added was 0.8% of the mass of the shell monomer pre-emulsion, the dropwise adding time was controlled to be 1 h, after the dropwise adding was completed, the reaction was continued for 4 h, to obtain a crosslinked acrylate coated butyl rubber core-shell emulsion.

[0104] The sound absorption coefficient of the sound absorption and insulation coating obtained in the example is tested to be 0.64 (125-4000 Hz) on average, the sound absorption coefficient in the frequency band of 500-2000 Hz is >0.7, the peak value (1000 Hz) is 0.82. The weighted sound insulation volume (Rw) is 36 dB (100-3000 Hz). The VOC content is ≤80 g / L. The adhesion is level 0. The water resistance test shows no blistering and no peeling. The alkali resistance test shows no abnormality. The flexibility test result is 2 mm (the coating has no cracks).

[0105] Example 6

[0106] A water-based polymer composite sound absorption and insulation coating, compared with Example 1, the difference is that the same amount of N,N'-methylene bisacrylamide crosslinking agent is used instead of isoprene crosslinking agent in the preparation process of the crosslinked acrylate coated butyl rubber core-shell emulsion.

[0107] The sound absorption coefficient of the sound absorption and insulation coating obtained in the example is tested to be 0.64 (125-4000 Hz) on average, the sound absorption coefficient in the frequency band of 500-2000 Hz is >0.7, the peak value (1000 Hz) is 0.82. The weighted sound insulation volume (Rw) is 36 dB (100-3000 Hz). The VOC content is ≤80 g / L. The adhesion is level 0. The water resistance test shows no blistering and no peeling. The alkali resistance test shows no abnormality. The flexibility test result is 2 mm (the coating has no cracks).

[0108] From the comparison results of Example 6 and Example 1, it can be concluded that the use of a crosslinking agent with poor affinity for butyl latex particles reduces the coating effect on butyl rubber emulsion particles, thereby reducing the overall uniformity of the coating film, and the sound absorption performance, sound insulation performance and adhesion of the obtained coating are reduced to a certain extent.

[0109] Comparative Example 1

[0110] A water-based polymer composite sound absorption and insulation coating, compared with Example 2, no porous sound absorption filler is added, the content of high-density sound insulation filler is increased to 35 parts, and the rest is the same.

[0111] The sound absorption coefficient of the sound absorption and insulation coating obtained in the example is tested to be 0.64 (125-4000 Hz) on average, the sound absorption coefficient in the frequency band of 500-2000 Hz is >0.7, the peak value (1000 Hz) is 0.82. The weighted sound insulation volume (Rw) is 36 dB (100-3000 Hz). The VOC content is ≤80 g / L. The adhesion is level 0. The water resistance test shows no blistering and no peeling. The alkali resistance test shows no abnormality. The flexibility test result is 2 mm (the coating has no cracks).

[0112] Comparative Example 2

[0113] A water-based polymer composite sound absorption and insulation coating, compared with Example 2, no high-density sound insulation filler is added, the content of porous sound absorption filler is increased to 35 parts, and the rest is the same.

[0114] The sound absorption and insulation coating obtained in the present comparative example was tested to have an average sound absorption coefficient of 0.50 (125-4000 Hz). The weighted sound reduction volume (Rw) was 20 dB (100-3000 Hz). The VOC content was ≤80 g / L. The adhesion was 0 level. The water resistance test showed no blistering and no peeling. The alkali resistance test showed no abnormality. The flexibility test result was 1 mm (no cracks in the coating).

[0115] Comparative Example 3

[0116] A water-based polymer composite sound absorption and insulation coating was prepared, which was different from Example 2 in that the cross-linked acrylate coated butyl rubber core-shell emulsion was not added, and the content of the silicone-acrylate emulsion was increased to 37.5 parts, and the rest was the same.

[0117] The sound absorption and insulation coating obtained in the present comparative example was tested to have an average sound absorption coefficient of 0.51 (125-4000 Hz). The weighted sound reduction volume (Rw) was 22 dB (100-3000 Hz). The VOC content was ≤80 g / L. The adhesion was 0 level. The water resistance test showed no blistering and no peeling. The alkali resistance test showed no abnormality. The flexibility test result was 2 mm (no cracks in the coating).

[0118] Comparative Example 4

[0119] A water-based polymer composite sound absorption and insulation coating was prepared, which was different from Example 2 in that the same amount of butyl latex (purchased on the market, solid content of 45%) was used to replace the cross-linked acrylate coated butyl rubber core-shell emulsion, and the rest was the same.

[0120] The sound absorption and insulation coating obtained in the present comparative example was tested to have an average sound absorption coefficient of 0.48 (125-4000 Hz). The weighted sound reduction volume (Rw) was 24 dB (100-3000 Hz). The VOC content was ≤80 g / L. The adhesion was 2 level. The water resistance test showed no blistering and no peeling. The alkali resistance test showed blistering. The flexibility test result was 2 mm (no cracks in the coating).

[0121] Comparative Example 5

[0122] A water-based polymer composite sound absorption and insulation coating was prepared, which was different from Example 2 in that no isoprene cross-linking agent was added in the preparation process of the cross-linked acrylate coated butyl rubber core-shell emulsion.

[0123] The sound absorption and insulation coating obtained in the present comparative example was tested to have an average sound absorption coefficient of 0.52 (125-4000 Hz). The weighted sound reduction volume (Rw) was 25 dB (100-3000 Hz). The VOC content was ≤80 g / L. The adhesion was 1 level. The water resistance test showed no blistering and no peeling. The alkali resistance test showed no abnormality. The flexibility test result was 2 mm (no cracks in the coating).

[0124] From the comparison results of the above Comparative Examples 1-3 and the Examples, it can be concluded that the porous sound-absorbing filler, the high-density sound-insulating filler and the butyl rubber elastic damping material are used in combination in the present application, which can synergistically improve the sound-absorbing coefficient and the sound-insulating volume of the coating. In addition, the addition of the crosslinked acrylate-coated butyl rubber core-shell emulsion can also increase the flexibility of the coating.

[0125] From the comparison results of the above Comparative Examples 4-5 and the Examples, it can be concluded that the sound-absorbing performance, the sound-insulating performance, the adhesion, the alkali resistance and the flexibility of the coating obtained by using the uncoated modified butyl latex (Comparative Example 4) are all obviously reduced. The reason is that the unmodified butyl rubber has poor compatibility with the silicone-acryl bonding resin and poor adhesion with the substrate, and is prone to continuous phase separation during the drying and film-forming process, which affects the overall uniformity of the coating film, thereby leading to a comprehensive reduction in performance. The butyl rubber particle coating effect of the un-crosslinked acrylate-modified butyl latex (Comparative Example 5) is poor, which also leads to a significant reduction in the sound-absorbing performance, the sound-insulating performance, the adhesion and the flexibility.

[0126] The above examples are preferred embodiments of the present application, but the embodiments of the present application are not limited by the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present application should be equivalent replacement methods, which are all included in the protection scope of the present application.

Claims

1. A water-based polymer composite sound-absorbing and sound-insulating paint, characterized by The components include the following components by weight parts: Silicone-acrylate emulsion 20-40 parts; Porous sound-absorbing filler 15-30 parts; High-density sound insulation filler 20-40 parts; Cross-linked acrylate coated butyl rubber core-shell emulsion 5-10 parts; Functional additives 1-8 parts; Deionized water 10-25 parts.

2. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 1, characterized in that The silicone-acrylate emulsion is prepared by the following method: The emulsifier is added to the reaction kettle containing deionized water, heated and stirred to dissolve, then the acrylate monomer, acrylic monomer and silane coupling agent monomer are mixed and emulsified to obtain a monomer emulsion; then the initiator solution is added dropwise for heat preservation and copolymerization reaction to obtain the silicone-acrylate emulsion.

3. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 2, characterized in that: The emulsifier is one or more of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate and nonylphenol polyoxyethylene ether; the amount of emulsifier added is 3-6% of the mass of deionized water; the temperature of the heating and stirring dissolution and heat preservation copolymerization reaction is 60-80℃.

4. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 2, characterized in that: The acrylate monomer is one or more of methyl methacrylate, ethyl acrylate and butyl acrylate; the amount of acrylate monomer added is 40-60% of the mass of the acrylic monomer; the acrylic monomer is one or both of acrylic acid and methacrylic acid; the silane coupling agent monomer is one or both of methacryloyloxypropyl trimethoxysilane and vinyl triethoxysilane; the amount of silane coupling agent monomer added is 10-20% of the mass of the acrylic monomer.

5. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 2, characterized in that: The solid content of the monomer emulsion is 40-60%; the initiator is potassium persulfate or ammonium persulfate, and the total amount of initiator added is 0.3-0.6% of the mass of the monomer emulsion.

6. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 1, characterized in that: The porous sound-absorbing filler is one or more of expanded perlite, hollow glass beads and porous ceramic powder with a particle size of 0.005-0.5mm; the high-density sound insulation filler is one or more of barite powder, ferrite powder and calcium carbonate powder with a particle size of 1-10μm; the mass ratio of the porous sound-absorbing filler to the high-density sound insulation filler is controlled to be 1:1-2; the functional additives include at least one of dispersants, defoamers, thickeners, film-forming aids and mildew-proof agents.

7. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 1, characterized in that: The cross-linked acrylate coated butyl rubber core-shell emulsion is prepared by the following method: (1) The acrylate monomer and diene crosslinking agent are added to the emulsifier aqueous solution and mixed and emulsified to obtain a shell monomer pre-emulsion; (2) The shell monomer pre-emulsion obtained in step (1) is added to the butyl latex and stirred and mixed and emulsified, then the initiator solution is added dropwise for heat polymerization reaction to obtain the cross-linked acrylate coated butyl rubber core-shell emulsion.

8. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 7, characterized in that: In the preparation of the cross-linked acrylate coated butyl rubber core-shell emulsion, the acrylate monomer is a mixture of methyl methacrylate and butyl acrylate in a mass ratio of 1:1-2; the diene crosslinking agent is one or more of isoprene, 1,4-pentadiene, 1,5-hexadiene and 2,5-dimethyl-1,5-hexadiene; the amount of diene crosslinking agent added is 0.5-3% of the mass of the acrylate monomer.

9. The water-based polymer composite sound-absorbing and sound-insulating paint according to claim 7, characterized in that: In the preparation of the crosslinked acrylate coated butyl rubber core-shell emulsion, the aqueous emulsifier solution is an aqueous solution of at least one of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, and nonylphenol polyoxyethylene ether; the mass concentration of the aqueous emulsifier solution is 2-5%; the solid content of the shell monomer pre-emulsion is 40-60%; the solid content of the butyl latex is 40-50%; the amount of the shell monomer pre-emulsion added is 30-50% of the mass of the butyl latex; the initiator is potassium persulfate or ammonium persulfate, and the total amount of the initiator added is 0.5-1.0% of the mass of the shell monomer pre-emulsion; and the temperature of the heating polymerization reaction is 60-80℃.

10. The method for preparing a water-based polymer composite sound-absorbing and sound-insulating paint according to claim 6, characterized in that: The preparation steps include: The dispersant and the defoaming agent are added to deionized water and stirred to mix uniformly, then the porous sound-absorbing filler and the high-density sound-insulating filler are added and stirred to grind, then the silicone-acrylic emulsion and the crosslinked acrylate coated butyl rubber core-shell emulsion are added and mixed uniformly, finally the film-forming aid and the thickening agent are added to adjust the viscosity to 8000-12000 mPa·s, and then the product is filtered and packaged to obtain the water-based high-molecular composite sound-absorbing and sound-insulating coating.