High-adhesion environment-friendly water-based sealant as well as preparation method and application thereof

Abstract

The invention provides a high-adhesion environment-friendly water-based sealant as well as a preparation method and application thereof, and the high-adhesion environment-friendly water-based sealant comprises the following components in parts by weight: 30-170 parts of a main emulsion, 0.5-5 parts of a dispersing agent, 0.5-15 parts of a plasticizer, 0.5-2 parts of a defoaming agent, 0.5-5 parts of an anti-freezing agent, 0-10 parts of a coupling agent, 30-200 parts of filler and 0-5 parts of a thixotropic agent, the main emulsion comprises an organic silicon modified acrylic emulsion and a second emulsion; the second emulsion comprises at least one of styrene-acrylic emulsion, acrylic emulsion, vinyl acetate emulsion and vinyl acetate-ethylene copolymer emulsion. The high-adhesive-force environment-friendly water-based sealant has a good bonding effect on different base materials, has good flexibility and extrusion performance, does not crack at a low temperature, and is environment-friendly and harmless to a human body.

Description

Technical Field

[0001] This invention belongs to the field of adhesive technology, specifically relating to a high-adhesion environmentally friendly water-based sealant, its preparation method, and its application. Background Technology

[0002] Sealants are common adhesives used to fill gaps in buildings, seal connections between components, and have a certain degree of adhesion. Most sealants on the market are silicone structural sealants and alcohol-based sealants. Silicone structural sealants have good adhesion, but they release an irritating odor during curing. Alcohol-based sealants release small methanol molecules during curing, which can harm the skin and respiratory tract; long-term exposure to this environment can even endanger people's physical and mental health.

[0003] With increasing demands for environmental protection and health, water-based sealants are widely used in interior decoration and other fields due to their characteristics of being free of organic solvents, having less odor, being environmentally friendly, and harmless to the human body. However, common water-based sealants on the market often exhibit low adhesion and poor bonding effects when applied to different materials, leading to many limitations in their practical applications.

[0004] Therefore, developing a healthy and environmentally friendly water-based sealant with high adhesion and good bonding effect is an urgent problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a high-adhesion environmentally friendly water-based sealant, its preparation method, and its application. The high-adhesion environmentally friendly water-based sealant exhibits high adhesion and good bonding effect, as well as good flexibility and extrusion performance. It does not crack at low temperatures and is environmentally friendly and harmless to the human body.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a high-adhesion environmentally friendly water-based sealant, which, by weight, comprises 30-170 parts of a main emulsion, 0.5-5 parts of a dispersant, 0.5-15 parts of a plasticizer, 0.5-2 parts of a defoamer, 0.5-5 parts of an antifreeze agent, 0-10 parts of a coupling agent, 30-200 parts of a filler, and 0-5 parts of a thixotropic agent; the main emulsion comprises a silicone-modified acrylic emulsion and a second emulsion; the second emulsion comprises at least one of styrene-acrylic emulsion, acrylic emulsion, vinyl acetate emulsion, and vinyl acetate-ethylene copolymer emulsion.

[0007] In this invention, an organosilicon-modified acrylic emulsion is compounded with a second emulsion and other components to form a strong adhesive layer on various substrates. This layer exhibits high adhesion, good bonding effect, good flexibility and sealing properties, and does not crack at low temperatures. Furthermore, it is environmentally friendly and harmless to the human body, thus enhancing the applicability and practicality of the sealant. This makes it widely applicable in interior decoration and can significantly improve the quality and safety of decoration.

[0008] In this invention, the main emulsion is 30 to 170 parts, for example, it can be 40 parts, 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts, 150 parts, 160 parts, etc.

[0009] In this invention, the dispersant is 0.5 to 5 parts, for example, it can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, etc.

[0010] In this invention, the plasticizer is 0.5 to 15 parts, for example, it can be 1 part, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts, etc.

[0011] In this invention, the defoamer is used in amounts of 0.5 to 2 parts, for example, 0.6 parts, 0.8 parts, 1 part, 1.2 parts, 1.4 parts, 1.6 parts, 1.8 parts, etc.

[0012] In this invention, the antifreeze is 0.5 to 5 parts, for example, it can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, etc.

[0013] In this invention, the coupling agent is 0 to 10 parts, for example, it can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, etc.

[0014] In this invention, the coupling agent includes at least one of 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane (Momentive Wetlink 78), γ-glycidoxypropyltrimethoxysilane (Momentive Coatosil 2287), and γ-methacryloyloxypropyltrimethoxysilane.

[0015] In this invention, the filler is 30 to 200 parts, for example, 40 parts, 60 parts, 80 parts, 100 parts, 120 parts, 140 parts, 160 parts, 180 parts, etc.

[0016] In this invention, the thixotropic agent is 0 to 5 parts, for example, it can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, etc.

[0017] Preferably, by weight, the main emulsion comprises 70-130 parts of silicone-modified acrylic emulsion (e.g., 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, etc.) and the second emulsion comprises 20-40 parts (e.g., 22, 24, 26, 28, 30, 32, 34, 36, 38, etc.).

[0018] In this invention, the solid content of the second emulsion is 30-70%, for example, it can be 35%, 40%, 45%, 50%, 55%, 60%, 65%, etc.

[0019] In some embodiments of the present invention, the mass ratio of the organosilicon-modified acrylic emulsion to the second emulsion is (2.2~3.98):1, for example, it can be 2.4:1, 2.6:1, 2.8:1, 3:1, 3.2:1, 3.4:1, 3.6:1, 3.8:1, etc.

[0020] Preferably, by weight, the raw materials for preparing the silicone-modified acrylic emulsion include 50-100 parts of pre-emulsified acrylate emulsion (e.g., 55, 60, 65, 70, 75, 80, 85, 90, 95, etc.), 0.1-5 parts of initiator (e.g., 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, etc.), and 0.5-5 parts of emulsifier (e.g., 1, 1.5, etc.). 4-8 parts of silane coupling agent (e.g., 4.2, 4.5, 4.8, 5, 5.2, 5.5, 5.8, 6, 6.2, 6.5, 6.8, 7, 7.2, 7.5, 7.8, etc.) and 0-20 parts of water (e.g., 2, 4, 6, 8, 10, 12, 14, 16, 18, etc.).

[0021] In this invention, the pre-emulsified acrylate emulsion comprises, by weight, 40-70 parts water (e.g., 42, 45, 48, 50, 52, 55, 58, 60, 62, 65, 68, etc.), 30-60 parts acrylate monomers (e.g., 32, 35, 38, 40, 42, 45, 48, 50, 52, 55, 58, etc.), and 0.5-1 part emulsifier (e.g., 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, etc.).

[0022] In this invention, the acrylate monomers in the pre-emulsified acrylate emulsion include at least one of methyl methacrylate, methyl acrylate, butyl acrylate, and isooctyl acrylate; the emulsifiers in the pre-emulsified acrylate emulsion include at least one of sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, Span series emulsifiers, and Tween series emulsifiers.

[0023] In this invention, the preparation method of the pre-emulsified acrylate emulsion includes: mixing water and an emulsifier, then adding acrylate monomers dropwise to the mixture, and stirring at 400-600 rpm for 20-40 min to obtain the pre-emulsified acrylate emulsion.

[0024] Preferably, the initiator comprises sodium persulfate and / or ammonium persulfate.

[0025] Preferably, the emulsifier includes at least one of sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, Span series emulsifiers, and Tween series emulsifiers.

[0026] Preferably, the silane coupling agent comprises at least one of 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane (Momentive Wetlink 78), γ-glycidoxypropyltrimethoxysilane (Momentive Coatosil 2287), and γ-methacryloyloxypropyltrimethoxysilane.

[0027] Preferably, the dispersant comprises at least one of ammonium salt block copolymers, polycarboxylate dispersants, and polyacrylamide.

[0028] Preferably, the plasticizer includes at least one of methyl chloroform, chloroparaffin, dioctyl phthalate, and dibutyl phthalate.

[0029] Preferably, the defoamer includes an organosilicone defoamer.

[0030] In this invention, the silicone defoamer includes at least one of Wacker's SC 120, SC 129, SC 132, and 855E.

[0031] Preferably, the antifreeze includes at least one of propylene glycol, glycerol, and ethylene glycol.

[0032] Preferably, the filler includes at least one of calcium carbonate, barium carbonate, titanium dioxide, quartz powder, aluminum hydroxide, alumina, silica, carbon black, talc, clay, and silica powder.

[0033] In some embodiments of the present invention, the filler comprises 70-130 parts of a first filler (e.g., 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, etc.) and 30-40 parts of a second filler (e.g., 31, 32, 33, 34, 35, 36, 37, 38, 39, etc.); the first filler comprises calcium carbonate or barium carbonate; the second filler comprises any one of titanium dioxide, quartz powder, aluminum hydroxide, and silica.

[0034] In some embodiments of the present invention, the filler comprises any one of the following: a combination of calcium carbonate and quartz powder, a combination of barium carbonate and titanium dioxide, a combination of calcium carbonate and silica, or a combination of calcium carbonate and aluminum hydroxide.

[0035] Preferably, the thixotropic agent includes at least one of organobentonite, fumed silica, hydroxyethyl cellulose, and polyacrylate.

[0036] In a second aspect, the present invention provides a method for preparing a high-adhesion environmentally friendly water-based sealant according to the first aspect, the preparation method comprising the following steps: The main emulsion, dispersant, plasticizer, defoamer, antifreeze, coupling agent, filler and thixotropic agent are mixed to obtain the high adhesion environmentally friendly water-based sealant.

[0037] Preferably, the mixture includes: (1) The silicone-modified acrylic emulsion, the second emulsion and the dispersant are mixed and dispersed evenly to obtain the first dispersion; (2) Mix the first dispersion with the filler and disperse evenly to obtain the second dispersion; (3) Mix the second dispersion with plasticizer, defoamer, antifreeze and coupling agent and disperse evenly to obtain the third dispersion; (4) Mix the third dispersion with the thixotropic agent and disperse evenly to obtain the high-adhesion environmentally friendly water-based sealant.

[0038] Preferably, the preparation method of the organosilicon-modified acrylic emulsion includes the following steps: (S1) Mix water, 20-80% of emulsifier and silane coupling agent, and react to obtain organosilicon prepolymer emulsion; (S2) The organosilicon prepolymer emulsion is mixed with the pre-emulsified acrylate emulsion and the remaining emulsifier, and an initiator is added dropwise to react and obtain the organosilicon modified acrylate emulsion.

[0039] Preferably, the temperature of the reaction in step (S1) is 75-90°C, for example, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C, 88°C, etc.; and the time is 40-80 min, for example, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min, etc.

[0040] In this invention, the reaction in step (S1) is carried out in the presence of a protective atmosphere; the protective atmosphere includes, but is not limited to, nitrogen.

[0041] In this invention, after the reaction in step (S1) is completed, the step of adjusting the pH to 6-7 using a pH adjuster, including ammonia, is further included.

[0042] Preferably, the pH value of the organosilicon prepolymer emulsion is 6 to 7, for example, it can be 6.2, 6.4, 6.6, 6.8, etc.

[0043] Preferably, the temperature during the addition of the initiator in step (S2) is 80-85°C, for example, 81°C, 82°C, 83°C, 84°C, etc.; the addition time is <2h, for example, 0.5h, 1h, 1.5h, etc.

[0044] Preferably, the temperature of the reaction in step (S2) is 90-100°C, for example, 92°C, 94°C, 96°C, 98°C, etc.; and the time is 1-3 hours, for example, 1.5 hours, 2 hours, 2.5 hours, etc.

[0045] In this invention, the mixing and dispersion time in step (1) is 20-40 min, for example, 25 min, 30 min, 35 min, etc.; the mixing and dispersion time in step (2) is 30-60 min, for example, 35 min, 40 min, 45 min, 50 min, 55 min, etc.; the mixing and dispersion in step (2) is carried out under vacuum conditions; the mixing and dispersion time in step (3) is 20-40 min, for example, 25 min, 30 min, 35 min, etc.; the mixing and dispersion in step (3) is carried out under vacuum conditions; the mixing and dispersion time in step (4) is 30-60 min, for example, 35 min, 40 min, 45 min, 50 min, 55 min, etc.; the mixing and dispersion in step (4) is carried out under vacuum conditions.

[0046] Thirdly, the present invention provides an application of the high-adhesion environmentally friendly water-based sealant as described in the first aspect in the construction field.

[0047] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0048] Compared with the prior art, the beneficial effects of the present invention are as follows: The high-adhesion environmentally friendly water-based sealant provided by this invention is formulated with silicone-modified acrylic emulsion, a second emulsion, and other components. It can form a strong adhesive layer on a variety of substrates, exhibiting high adhesion, good bonding effect, and excellent flexibility and sealing properties. At the same time, it is environmentally friendly and harmless to the human body, enhancing the sealant's applicability and practicality, making it widely applicable in interior decoration and significantly improving decoration quality and safety. Detailed Implementation

[0049] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0050] All materials used in this invention can be purchased commercially or prepared using conventional methods. Unless otherwise specified, the materials used in this invention are as follows.

[0051] lotion Pre-emulsified acrylate emulsion: prepared in the laboratory, the preparation steps are as follows: 60 parts of deionized water and 0.8 parts of emulsifier (sodium dodecyl sulfate) are mixed and stirred for 10 min, and then 50 parts of acrylate monomers (a mixture of methyl methacrylate, methyl acrylate, butyl acrylate and isooctyl acrylate in a mass ratio of 1:1:1:1) are slowly added dropwise. The mixture is stirred slowly at room temperature and 500 rpm for 30 min to obtain a uniformly dispersed pre-emulsified emulsion, which is the pre-emulsified acrylate emulsion.

[0052] Acrylic emulsion: Shenzhen Yoshida Chemical Co., Ltd., E0504.

[0053] Vinyl acetate emulsion: Shenzhen Yoshida Chemical Co., Ltd., DA-102-H.

[0054] dispersant Ammonium salt block copolymer: Sanopco SN 5029 dispersant.

[0055] Polycarboxylate dispersant: Sanopco SN 5040 dispersant.

[0056] thixotropic agents Polyacrylate: Guangdong Zhongtai Lianhua New Materials Co., Ltd., AG-503, AG-201.

[0057] Hydroxyethyl cellulose: Zhengzhou Chengrui Chemical Products Co., Ltd., hydroxyethyl cellulose.

[0058] Organic bentonite: Guangzhou Zhanfei Chemical Technology Co., Ltd., BP-186.

[0059] Example 1 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which, by weight, comprises 103.5 parts of main emulsion, 80 parts of calcium carbonate, 40 parts of quartz powder, 1.5 parts of organobentonite, 8 parts of dioctyl phthalate, 3 parts of ammonium salt block copolymer, 1 part of Wacker SC 120 defoamer, 2 parts of propylene glycol, and 3 parts of Momentive Coatosil 2287 coupling agent.

[0060] By weight, the main emulsion comprises 73.5 parts of silicone-modified acrylic emulsion and 30 parts of acrylic emulsion.

[0061] The raw materials for preparing the silicone-modified acrylic emulsion, by weight, include 50 parts of pre-emulsified acrylic emulsion, 1.5 parts of sodium persulfate, 2 parts of sodium dodecyl sulfate, 15 parts of water, and 5 parts of Momentive Wetlink 78 coupling agent.

[0062] This embodiment provides a method for preparing the high-adhesion environmentally friendly water-based sealant, specifically including the following steps: (1) Add water, 43% of the formula amount of emulsifier (i.e., 43% of the total mass of emulsifier) ​​and Momentive Wetlink 78 to a three-necked flask, purge with nitrogen, stir at 80°C for 60 min, and then adjust the pH value to about 6.5 with ammonia water to obtain an organosilicon prepolymer emulsion; then heat and stir the organosilicon prepolymer emulsion, the remaining emulsifier, and the pre-emulsified acrylic emulsion at 80°C, add the initiator dropwise over 2 h, and after the addition is complete, raise the temperature to 90°C and keep it at that temperature for 2 h. After the reaction is complete, cool naturally and discharge to obtain an organosilicon modified acrylic emulsion. (2) Mix and stir the silicone-modified acrylic emulsion, acrylic emulsion and ammonium salt block copolymer for 30 min until uniformly dispersed to obtain a first dispersion; then add calcium carbonate and quartz powder to the first dispersion, and stir under vacuum for 60 min until uniformly dispersed to obtain a second dispersion; add dioctyl phthalate, Wacker SC 120 defoamer, propylene glycol and Momentive Coatosil 2287 coupling agent to the second dispersion, and stir under vacuum for 30 min until uniformly dispersed to obtain a third dispersion; add organobentonite to the third dispersion, and stir under vacuum for 60 min until uniformly dispersed, and then discharge the sample to obtain the high-adhesion environmentally friendly water-based sealant.

[0063] Example 2 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which, by weight, comprises 99.5 parts of a main emulsion, 70 parts of barium carbonate, 35 parts of titanium dioxide, 1.5 parts of polyacrylate, 6 parts of methyl chloride, 2.5 parts of ammonium salt block copolymer, 1.5 parts of Wacker SC 120 defoamer, 2 parts of propylene glycol, and 4 parts of Momentive Coatosil 2287 coupling agent.

[0064] By weight, the main emulsion comprises 79.5 parts of silicone-modified acrylic emulsion and 20 parts of acrylic emulsion.

[0065] The raw materials for preparing the silicone-modified acrylic emulsion, by weight, include 60 parts of pre-emulsified acrylic emulsion, 1.5 parts of ammonium persulfate, 2 parts of sodium dodecylbenzenesulfonate, 15 parts of water, and 4 parts of Momentive Wetlink 78 coupling agent.

[0066] This embodiment provides a method for preparing the high-adhesion environmentally friendly water-based sealant, and the specific steps are the same as in Embodiment 1.

[0067] Example 3 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which, by weight, comprises 167.5 parts of a main emulsion, 130 parts of calcium carbonate, 30 parts of silica, 1 part of hydroxyethyl cellulose, 10 parts of dioctyl phthalate, 4 parts of ammonium salt block copolymer, 2 parts of Wacker SC 120 defoamer, 2 parts of propylene glycol, and 2 parts of γ-methacryloyloxypropyltrimethoxysilane.

[0068] The main emulsion comprises, by weight, 127.5 parts of silicone-modified acrylic emulsion and 40 parts of acrylic emulsion.

[0069] The raw materials for preparing the silicone-modified acrylic emulsion, by weight, include 100 parts of pre-emulsified acrylic emulsion, 1.5 parts of sodium persulfate, 3 parts of sodium dodecylbenzenesulfonate, 15 parts of water, and 8 parts of Momentive Wetlink 78 coupling agent.

[0070] This embodiment provides a method for preparing the high-adhesion environmentally friendly water-based sealant, and the specific steps are the same as in Embodiment 1.

[0071] Example 4 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which, by weight, comprises 131 parts of a main emulsion, 100 parts of calcium carbonate, 30 parts of aluminum hydroxide, 2 parts of hydroxyethyl cellulose, 8 parts of dibutyl phthalate, 3 parts of polycarboxylate dispersant, 2 parts of Wacker 855E defoamer, 2 parts of propylene glycol, and 3 parts of γ-methacryloyloxypropyltrimethoxysilane.

[0072] The main emulsion comprises, by weight, 96 parts of silicone-modified acrylic emulsion and 35 parts of vinyl acetate emulsion.

[0073] The raw materials for preparing the silicone-modified acrylic emulsion, by weight, include 75 parts of pre-emulsified acrylic emulsion, 1.5 parts of ammonium persulfate, 2.5 parts of sodium dodecyl sulfate, 12 parts of water, and 5 parts of Momentive Wetlink 78 coupling agent.

[0074] This embodiment provides a method for preparing the high-adhesion environmentally friendly water-based sealant, and the specific steps are the same as in Embodiment 1.

[0075] Example 5 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which differs from Embodiment 3 only in that the main emulsion includes 60 parts of silicone-modified acrylic emulsion and 107.5 parts of acrylic emulsion. Other components, dosages, and preparation methods are the same as in Embodiment 3.

[0076] Example 6 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which differs from Embodiment 3 only in that the main emulsion includes 150 parts of silicone-modified acrylic emulsion and 17.5 parts of acrylic emulsion. Other components, dosages, and preparation methods are the same as in Embodiment 3.

[0077] Example 7 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which differs from Embodiment 3 only in that calcium carbonate is replaced with an equal mass of talc powder and silica is replaced with an equal mass of alumina. Other components, dosages, and preparation methods are the same as in Embodiment 3.

[0078] Example 8 This embodiment provides a high-adhesion environmentally friendly water-based sealant, which differs from Embodiment 3 only in that the mass of calcium carbonate is 160 parts, and there is no silica. The other components, dosages, and preparation methods are the same as in Embodiment 3.

[0079] Comparative Example 1 This comparative example provides a water-based sealant, which, by weight, comprises 100 parts acrylic emulsion, 150 parts calcium carbonate, 2 parts hydroxyethyl cellulose, 8 parts dioctyl phthalate, 3 parts polycarboxylate dispersant, 1.5 parts Wacker SC129 defoamer, 2 parts propylene glycol, and 3 parts Momentive Wetlink 78 coupling agent.

[0080] This comparative example provides a method for preparing a water-based sealant, specifically including the following steps: (2) Mix the acrylic emulsion and polycarboxylate dispersant for 30 min until uniformly dispersed; then add calcium carbonate and stir under vacuum for 60 min until uniformly dispersed; then add dioctyl phthalate, Wacker SC 129 defoamer, propylene glycol and Momentive Wetlink 78 coupling agent and stir under vacuum for 30 min until uniformly dispersed; finally add hydroxyethyl cellulose and stir under vacuum for 60 min until uniformly dispersed. Discharge the sample to obtain the water-based sealant.

[0081] Comparative Example 2 This comparative example provides a water-based sealant, which, by weight, comprises 175.5 parts of a main emulsion, 240 parts of calcium carbonate, 0.5 parts of fumed silica, 12 parts of dioctyl phthalate, 4 parts of polycarboxylate dispersant, 2 parts of Wacker SC 120 defoamer, and 2 parts of propylene glycol.

[0082] The main emulsion comprises, by weight, 125.5 parts of silicone-modified acrylic emulsion and 50 parts of acrylic emulsion.

[0083] The raw materials for preparing the silicone-modified acrylic emulsion, by weight, include 100 parts of pre-emulsified acrylic emulsion, 1.5 parts of sodium persulfate, 3 parts of sodium dodecyl sulfonate, 15 parts of water, and 6 parts of Momentive Wetlink 78 coupling agent.

[0084] This comparative example provides a method for preparing the water-based sealant, with the specific steps being the same as in Example 1.

[0085] Comparative Example 3 This comparative example provides a water-based sealant, which differs from Example 3 only in that the acrylic emulsion is replaced with an equal mass of epoxy resin emulsion (Shenzhen Yoshida Chemical Co., Ltd. E0430). All other components, dosages, and preparation methods are the same as in Example 3.

[0086] Performance testing The water-based sealant provided in the test examples and comparative examples, in accordance with the test methods of standard JC / T 484, was tested under standard conditions (23±2℃, RH 50±5%) for its hand-pull adhesion performance, tensile properties, and other properties on various substrates of anodized aluminum I-beams. The specific test results are shown in Table 1 (hand-pull adhesion performance of water-based sealant) and Table 2 (tensile and other properties of water-based sealant on anodized aluminum / anodized aluminum I-beams).

[0087] In Table 1, the hand-pull adhesion performance of water-based sealants to different substrates is determined by the adhesion failure. Cohesive failure indicates that the failure mode is that the adhesive sample breaks / destroys, and the substrate is not obviously exposed. Cohesive failure indicates that the hand-pull adhesion performance is the best, which is better than adhesion failure. The value in adhesion failure indicates the percentage of the failure area to the total adhesion area. For example, "50% adhesion failure" means that the failure area accounts for 50% of the total adhesion area. The larger the value, the worse the adhesion performance.

[0088] The bond failure conditions in Table 2 are determined by tensile testing using a tensile testing machine.

[0089] Table 1 Table 2 As shown in Tables 1 and 2, the water-based sealant provided by this invention is formulated with silicone-modified acrylic emulsion, a second emulsion, and other components. It can form a strong adhesive layer on various substrates, exhibiting high adhesion, good bonding effect, and excellent flexibility and sealing properties. Furthermore, it is environmentally friendly and harmless to the human body. The water-based sealant has an elongation at break ≥335%, an extrusion rate ≥1327 mL / min, and exhibits no cracking at -5℃. The area of ​​adhesion failure on different substrates is ≤50%.

[0090] As can be seen from Comparative Example 1, the water-based sealant does not contain silicone-modified acrylic emulsion, has poor adhesion to glass and ceramics, and has poor elongation at break and extrusion performance.

[0091] As can be seen from Comparative Example 2, the water-based sealant has a high content of main emulsion and filler, resulting in poor adhesion to various substrates, as well as poor elongation at break, extrusion performance, and low-temperature flexibility.

[0092] As can be seen from Comparative Example 3, the water-based sealant obtained by not using a specific type of second emulsion and compounding with silicone-modified acrylic emulsion has poor adhesion to various substrates, and poor elongation at break, extrusion performance and low-temperature flexibility.

[0093] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A high-adhesion, environmentally friendly water-based sealant, characterized in that, By weight, the high-adhesion environmentally friendly water-based sealant comprises 30-170 parts of main emulsion, 0.5-5 parts of dispersant, 0.5-15 parts of plasticizer, 0.5-2 parts of defoamer, 0.5-5 parts of antifreeze, 0-10 parts of coupling agent, 30-200 parts of filler, and 0-5 parts of thixotropic agent; The main emulsion comprises a silicone-modified acrylic emulsion and a second emulsion; The second emulsion includes at least one of styrene-acrylic emulsion, acrylic emulsion, vinyl acetate emulsion, and vinyl acetate-ethylene copolymer emulsion.

2. The high-adhesion environmentally friendly water-based sealant according to claim 1, characterized in that, The main emulsion comprises, by weight, 70-130 parts of silicone-modified acrylic emulsion and 20-40 parts of a second emulsion.

3. The high-adhesion environmentally friendly water-based sealant according to claim 1 or 2, characterized in that, The raw materials for preparing the organosilicon-modified acrylic emulsion, by weight, include 50-100 parts of pre-emulsified acrylic emulsion, 0.1-5 parts of initiator, 0.5-5 parts of emulsifier, 4-8 parts of silane coupling agent, and 0-20 parts of water. Preferably, the initiator comprises sodium persulfate and / or ammonium persulfate; Preferably, the emulsifier includes at least one of sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, Span series emulsifiers, and Tween series emulsifiers; Preferably, the silane coupling agent comprises at least one of 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane.

4. The high-adhesion environmentally friendly water-based sealant according to any one of claims 1 to 3, characterized in that, The dispersant includes at least one of ammonium salt block copolymers, polycarboxylate dispersants, and polyacrylamide; Preferably, the plasticizer includes at least one of methyl chloroform, chloroparaffin, dioctyl phthalate, and dibutyl phthalate.

5. The high-adhesion environmentally friendly water-based sealant according to any one of claims 1 to 4, characterized in that, The defoamer includes silicone defoamers; Preferably, the antifreeze includes at least one of propylene glycol, glycerol, and ethylene glycol.

6. The high-adhesion environmentally friendly water-based sealant according to any one of claims 1 to 5, characterized in that, The filler includes at least one of the following: calcium carbonate, barium carbonate, titanium dioxide, quartz powder, aluminum hydroxide, alumina, silica, carbon black, talc, clay, and silica powder. Preferably, the thixotropic agent includes at least one of organobentonite, fumed silica, hydroxyethyl cellulose, and polyacrylate.

7. A method for preparing a high-adhesion environmentally friendly water-based sealant according to any one of claims 1 to 6, characterized in that, The preparation method includes the following steps: The main emulsion, dispersant, plasticizer, defoamer, antifreeze, coupling agent, filler and thixotropic agent are mixed to obtain the high adhesion environmentally friendly water-based sealant.

8. The preparation method according to claim 7, characterized in that, The mixture includes: (1) The silicone-modified acrylic emulsion, the second emulsion and the dispersant are mixed and dispersed evenly to obtain the first dispersion; (2) Mix the first dispersion with the filler and disperse evenly to obtain the second dispersion; (3) Mix the second dispersion with plasticizer, defoamer, antifreeze and coupling agent and disperse evenly to obtain the third dispersion; (4) Mix the third dispersion with the thixotropic agent and disperse evenly to obtain the high-adhesion environmentally friendly water-based sealant.

9. The preparation method according to claim 8, characterized in that, The preparation method of the organosilicon-modified acrylic emulsion includes the following steps: (S1) Mix water, 20-80% of emulsifier and silane coupling agent, and react to obtain organosilicon prepolymer emulsion; (S2) The organosilicon prepolymer emulsion is mixed with the pre-emulsified acrylic emulsion and the remaining emulsifier, and an initiator is added dropwise to react to obtain the organosilicon modified acrylic emulsion. Preferably, the reaction in step (S1) is carried out at a temperature of 75–90°C for 40–80 min. Preferably, the pH value of the organosilicon prepolymer emulsion is 6-7; Preferably, the temperature during the addition of the initiator in step (S2) is 80-85°C, and the addition time is <2h; Preferably, the reaction in step (S2) is carried out at a temperature of 90–100°C for 1–3 hours.

10. The application of a high-adhesion environmentally friendly water-based sealant as described in any one of claims 1 to 6 in the construction field.

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