Air-drying prepolymer and preparation method thereof, PMMA elastic waterproof coating

Abstract

This application discloses an air-drying prepolymer and its preparation method, as well as a PMMA elastic waterproof coating. The air-drying prepolymer includes one or more combinations of compounds represented by formulas (1) to (4): in formulas (1) to (4), R1 is selected from C1-C8 alkylene groups, and R2 is selected from H, C1-C8 alkyl groups, and hydroxyl-substituted C1-C8 alkyl groups. The PMMA elastic waterproof coating and its respective preparation method in the embodiments of this application use an air-drying prepolymer mixed with PUA resin and other components in the PMMA elastic waterproof coating to introduce the air-drying prepolymer into the PUA resin, and then into the structure of the PMMA elastic waterproof coating. Utilizing the good storage stability of the air-drying prepolymer containing oxygen-absorbing functional groups, the influence of oxygen inhibition on the curing behavior of the PMMA elastic coating can be effectively reduced.

Description

Technical Field

[0001] The present application belongs to the technical field of waterproof coatings, and in particular relates to an air-drying prepolymer and a preparation method thereof, and a PMMA elastic waterproof coating. Background Art

[0002] The name of PMMA waterproof material comes from the use of MMA monomer as an active diluent. In the system, the initiator and the reducing agent contact each other and react to generate active free radicals. The active free radicals induce the MMA monomer to undergo polymerization to form a polymerized polymer, namely PMMA. Since the saturated vapor pressure of the MMA monomer is low, operators who apply the paint at the paint construction site will inhale a large amount of MMA gas. In addition, the initiator and the reducing agent act very quickly, and the free radical quenching speed is also very fast, which can easily cause MMA to remain in the final coating before it reacts completely. This will have an immeasurable impact on the health of people and the water environment in the environment where this paint is used.

[0003] In addition, PMMA waterproof coatings are susceptible to oxygen attack and incomplete curing, commonly known as oxygen inhibition, which is more prominent in scenes with high wind speed, low air pressure and high humidity. Existing PMMA waterproof coatings are high glass transition temperature coatings, which are used in places with small grass-roots activities such as floors and railway tracks. The scenes are limited and it is difficult to adapt to scenes with large grass-roots activities. Summary of the invention

[0004] The PMMA elastic waterproof coating and respective preparation methods provided in the embodiments of the present application can effectively reduce the influence of oxygen inhibition on the curing behavior of the PMMA elastic coating.

[0005] In a first aspect, the present application provides an air-drying prepolymer, comprising one or a combination of compound structures represented by formula (1) to formula (4):

[0006]

[0007] In formula (1) to formula (4), R1 is selected from C1-C8 alkylene, and R2 is selected from H, C1-C8 alkyl, and hydroxy-substituted C1-C8 alkyl.

[0008] In the embodiment of the first aspect of the present application, in formula (1) to formula (4), R1 is selected from methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, and octylene.

[0009] In the embodiment of the first aspect of the present application, in formula (1) to formula (4), R2 is selected from H, methyl, ethyl, propyl, butyl, pentyl, n-hexyl, n-heptyl, n-octyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, hydroxypentyl, hydroxyhexyl, hydroxyheptyl, and hydroxyoctyl.

[0010] In the embodiment of the first aspect of the present application, the compound of the structure shown in formula (1) includes:

[0011]

[0012] In the embodiment of the first aspect of the present application, the compound of the structure shown in formula (2) includes:

[0013]

[0014] In the embodiment of the first aspect of the present application, the compound of the structure shown in formula (3) includes:

[0015]

[0016] In the embodiment of the first aspect of the present application, the compound of the structure shown in formula (4) includes:

[0017]

[0018] In a second aspect, the present application provides a method for preparing an air-drying prepolymer, comprising:

[0019] Compounds of structures represented by formula (9) to formula (11) are provided respectively, one or a combination of the compounds of structures represented by formula (9) to formula (10) is used as raw material A, and a compound of structure represented by formula (11) is used as raw material B:

[0020]

[0021] In formula (9), R3 is H or methyl; in formula (10), R4 is H or methyl;

[0022]

[0023] In formula (11), R5 is H, C1-C8 alkyl, or C1-C8 alkyl substituted with hydroxyl, and R6 is C1-C8 alkylene;

[0024] Raw material A, raw material B, a solid acid catalyst and a polymerization inhibitor are mixed and reacted in a ratio of 1:(1-3):(0.01wt.%-0.06wt.%):(0.05wt.%-0.1wt.%) to obtain an air-drying prepolymer; wherein the raw material A and the raw material B are in a molar ratio, and the ratio of the solid acid catalyst and the polymerization inhibitor is calculated as a percentage of the total mass of the raw material A and the raw material B.

[0025] In an embodiment of the second aspect of the present application, the compound of the structure represented by formula (9) is nadic anhydride or methyl nadic anhydride.

[0026] In an embodiment of the second aspect of the present application, the compound of the structure represented by formula (10) is tetrahydrophthalic anhydride or methyltetrahydrophthalic anhydride.

[0027] In an embodiment of the second aspect of the present application, the compound represented by formula (11) is selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

[0028] In an embodiment of the second aspect of the present application, the solid acid catalyst is selected from β molecular sieve, strong acid resin, sulfuric acid / zirconium oxide, and tungstic acid / zirconium oxide.

[0029] In the embodiment of the second aspect of the present application, the β molecular sieve refers to a high-silicon zeolite having a three-dimensional cross-structured twelve-membered ring channel, and the chemical composition is: |Na +7 |[Al7Si 57 O 128 ]-BEA, selected from NE-H00-02, NE-H00-04.

[0030] In an embodiment of the second aspect of the present application, the strong acid resin is selected from Rohm and Haas Amberlyst 15WET and D005 macroporous strong acid cationic resin.

[0031] In an embodiment of the second aspect of the present application, the polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone, methylhydroquinone or a combination thereof.

[0032] In the third aspect, the present application provides a PUA resin, which is prepared from polyether polyol, polyisocyanate, a capping agent, and a hydroxy acrylate compound; wherein the molar ratio R of -NCO in the polyisocyanate and -OH in the polyether polyol is 1.1 to 1.5, and the molar ratio of the capping agent and the hydroxy acrylate compound is (0.1 to 0.5):1, calculated based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate.

[0033] In an embodiment of the third aspect, the PUA resin is diluted with an acrylate monomer, and the amount of the acrylate monomer accounts for 20% to 40% of the total mass of the PUA resin.

[0034] In a fourth aspect, the present application provides a method for preparing a PUA resin, comprising: providing a polyether polyol and a polyisocyanate, wherein the molar ratio R of -NCO in the polyisocyanate to -OH in the polyether polyol is 1.1 to 1.5; mixing the polyether polyol and the polyisocyanate for reaction to obtain a pre-finished product; adding an inhibitor, a capping agent, and a hydroxy acrylate compound to the pre-finished product in sequence under catalyst conditions to obtain a PUA resin; wherein, based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate, the molar ratio of the inhibitor, the capping agent, and the hydroxy acrylate compound is 0.06:(0.1 to 0.5):1.

[0035] In an embodiment of the fourth aspect, the preparation method of the PUA resin further includes: mixing the PUA resin with an acrylate monomer to obtain a PUA resin dilution solution; wherein the amount of the acrylate monomer accounts for 20% to 40% of the total mass of the PUA resin.

[0036] In an embodiment of the fourth aspect, providing the polyether polyol includes heating the polyether polyol to 103° C. to 108° C. and performing vacuum dehydration to reduce the moisture content of the polyether polyol to below 0.5%.

[0037] In the embodiment of the present application, the molecular weight of the polyether polyol is in the range of 1000 to 6000, and the hydroxyl functionality is 2 to 3.

[0038] In an embodiment of the present application, the polyether polyol is selected from polyether diol, polyether triol or a combination thereof.

[0039] In an embodiment of the third aspect of the present application, the mass ratio of the polyether diol to the polyether triol is 1:(0.5-0.8).

[0040] In an embodiment of the present application, the polyether diol includes DL-2000D and / or DL1000D; the polyether triol includes EP330N and / or MN1000.

[0041] In an embodiment of the present application, the polyisocyanate is selected from toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI) or a combination thereof.

[0042] In the embodiments of the present application, among the polyisocyanates, toluene diisocyanate and dicyclohexylmethane diisocyanate, toluene diisocyanate and isophorone diisocyanate, diphenylmethane diisocyanate and dicyclohexylmethane diisocyanate, and diphenylmethane diisocyanate and isophorone diisocyanate can be mixed in groups and used, and the molar ratio thereof is 1:2 to 3.

[0043] In the embodiment of the present application, after the polyether polyol and the polyisocyanate react to obtain a prepolymer, a catalyst is used to catalyze the reaction of the end-capping agent and the hydroxy acrylate compound with the prepolymer.

[0044] In an embodiment of the present application, the catalyst is selected from dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dibutyltin di(dodecylsulfide), organic bismuth, organic zinc or a combination thereof. Optionally, the organic bismuth catalyst is selected from DY-20, BiCAT8118, BiCAT8108, BiCAT8124. The organic zinc is selected from DY-5350. Organic bismuth and organic zinc can be used in combination at a ratio of (1:10) to (10:1).

[0045] In the embodiment of the present application, the amount of the catalyst used is 0.1 wt.% to 0.5 wt.% calculated as a mass percentage based on the total weight of the PUA resin product.

[0046] In an embodiment of the present application, the polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone, and methylhydroquinone.

[0047] In an embodiment of the present application, the capping agent is selected from benzyl alcohol, n-octanol, hydroxybutyric acid, isobornyl alcohol or a combination thereof.

[0048] In an embodiment of the present application, the hydroxyacrylate compound is selected from hydroxyethyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate or a combination thereof.

[0049] In an embodiment of the present application, the acrylic acid ester monomer is selected from methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate or a combination thereof.

[0050] In a fifth aspect, an embodiment of the present application provides a PMMA elastic waterproof coating, comprising: component A and component B; wherein, in parts by weight, component A comprises:

[0051] PUA resin, 100 parts by weight, the PUA resin being the above-mentioned PUA resin or a PUA resin prepared according to the preparation method of the PUA resin;

[0052] 20 to 100 parts by weight of the air-drying prepolymer based on 100 parts by weight of the PUA resin is the above-mentioned air-drying prepolymer:

[0053] Based on 100 parts by weight of PUA resin, the active diluent is 40 to 250 parts by weight:

[0054] Based on 100 parts by weight of PUA resin, 50 to 225 parts by weight of powder:

[0055] 20 to 100 parts by weight of plasticizer based on 100 parts by weight of PUA resin:

[0056] 20 to 90 parts by weight of reinforcing agent based on 100 parts by weight of PUA resin:

[0057] Based on 100 parts by weight of PUA resin, 10 to 50 parts by weight of air drying agent:

[0058] 8 to 50 parts by weight of reducing agent based on 100 parts by weight of PUA resin:

[0059] 4 to 25 parts by weight of anti-settling agent based on 100 parts by weight of PUA resin:

[0060] 2 to 10 parts by weight of an anti-ultraviolet aging agent based on 100 parts by weight of PUA resin:

[0061] 2 to 10 parts by weight of antioxidant based on 100 parts by weight of PUA resin:

[0062] Component B is an oxidizing agent.

[0063] In an embodiment of the fifth aspect of the present application, the mass ratio of component A to component B is 100:(1-5).

[0064] In an embodiment of the fifth aspect of the present application, the powder is selected from heavy calcium carbonate, light calcium carbonate, talc, barium sulfate, aluminum hydroxide, titanium dioxide, fumed silica, nano calcium carbonate or a combination thereof.

[0065] In an embodiment of the fifth aspect of the present application, the particle size of the powder is 400 mesh to 2000 mesh.

[0066] In an embodiment of the fifth aspect of the present application, the active diluent is selected from methacrylic acid, methyl methacrylate, styrene, butyl acrylate, isooctyl acrylate, glycidyl acrylate, hydroxyethyl methacrylate, ethyl acrylate or a combination thereof.

[0067] In an embodiment of the fifth aspect of the present application, the air-drying agent is refined or semi-refined paraffin.

[0068] In the embodiment of the fifth aspect of the present application, the anti-ultraviolet aging agent is selected from UV-326, UV-329 or a combination thereof.

[0069] In the embodiment of the fifth aspect of the present application, the antioxidant is selected from 1010, 686 or a combination thereof.

[0070] In an embodiment of the fifth aspect of the present application, the reducing agent is selected from diethanolamine, dimethylethanolamine, N,N-diethylhydroxylamine, N,N-dimethyl-p-toluidine, N,N-diethylaniline or a combination thereof.

[0071] In an embodiment of the fifth aspect of the present application, the anti-settling agent is selected from fumed silica, organic bentonite or polyurea anti-settling agent.

[0072] In an embodiment of the fifth aspect of the present application, the reinforcing agent is selected from 3102 Mitsubishi resin, 950 Mitsubishi resin or a combination thereof.

[0073] In an embodiment of the fifth aspect of the present application, the plasticizer is selected from acetyl tributyl citrate, dioctyl terephthalate, dioctyl phthalate or a combination thereof.

[0074] In an embodiment of the fifth aspect of the present application, the oxidant is selected from benzoyl peroxide, cumene hydroperoxide or a combination thereof.

[0075] In an embodiment of the fifth aspect of the present application, component A of the PMMA elastic waterproof coating further includes: 1 to 15 parts by weight of a pH buffer based on 100 parts by weight of PUA resin.

[0076] In an embodiment of the fifth aspect of the present application, the pH buffer is selected from tartaric acid, potassium dihydrogen phosphate, sodium bicarbonate or a combination thereof.

[0077] In an embodiment of the fifth aspect of the present application, component A of the PMMA elastic waterproof coating further includes: 2 to 10 parts by weight of color paste based on 100 parts by weight of PUA resin.

[0078] In an embodiment of the fifth aspect of the present application, the color paste is selected from emerald green, iron red, orange or a combination thereof.

[0079] In the sixth aspect, the embodiments of the present application provide a method for preparing a PMMA elastic waterproof coating, comprising: dispersing PUA resin, powder, active diluent, air drying agent, plasticizer, anti-ultraviolet aging agent, antioxidant, reducing agent, anti-settling agent, reinforcing agent, and air drying prepolymer according to the composition and content of the PMMA elastic waterproof coating to obtain component A; mixing component B with component A to obtain the PMMA elastic waterproof coating.

[0080] In the embodiment of the sixth aspect of the present application, the pH buffer and / or color paste are dispersed with other components in component A.

[0081] The PMMA elastic waterproof coating and preparation method thereof in the embodiments of the present application use an air-drying prepolymer to mix with a PUA resin and other components in the PMMA elastic waterproof coating, introduce the air-drying prepolymer into the PUA resin, and then introduce it into the structure of the PMMA elastic waterproof coating, and utilize the good storage stability of the air-drying prepolymer containing oxygen-absorbing functional groups to effectively reduce the influence of oxygen inhibition on the curing behavior of the PMMA elastic coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0083] Figure 1 This is the infrared absorption spectrum of the air-drying prepolymer prepared in Example 1.

[0084] Figure 2 This is the HR-MS spectrum of the air-drying prepolymer prepared in Example 1.

[0085] Figure 3 The air-drying prepolymer prepared in Example 1 1 HNMR spectrum.

[0086] Figure 4 It is a schematic diagram of the equipment structure for surface reaction thermal testing.

[0087] Explanation of the reference numerals: 1. Metal outer cylinder surface is plated with a shell; 2. Metal inner cylinder surface is plated with a shell; 3. Insulated handle; 4. Insulated frame; 5. Insulated cover; 6. Thermometer; 7. Wires for connecting the digital display. DETAILED DESCRIPTION

[0088] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0089] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0090] PMMA coating: PMMA coating consists of acrylate monomer (usually MMA, because it is low-toxic and cheap), oxidant, reductant, and powder. When used, mix the concentrated components and then apply them on the base layer.

[0091] Free radical curing: The contact between the oxidant (RR) and the reductant can quickly generate active free radicals R* and release a large amount of heat; the active free radical R* will attack the acrylate monomer with a double bond to obtain an active monomer free radical RA*; the active monomer free radical RA* continues to attack the acrylate monomer with a double bond to obtain an active monomer free radical RAA* (RA...A*), and so on. The cycle continues until it encounters R* for disproportionation termination, and the molecular weight no longer increases, and finally a polymer of RAAR is obtained. At this time, the molecular weight of the polymer is about tens of thousands to hundreds of thousands. The activity level of the polymer is very low at the microscopic level, and it behaves as a hard material at the macroscopic level. This process is called free radical curing or free radical addition.

[0092] Oxygen inhibition: During the free radical curing process, the active monomer free radical RAA* encounters R* for disproportionation termination, and finally obtains the polymer of RAAR; and oxygen itself is also an active free radical, so oxygen will react with the active monomer free radical RAA* to obtain RAAO2. At this time, the molecular weight of the polymer no longer increases, and this situation is called oxygen inhibition. Oxygen inhibition will cause the microscopic activity of the polymer to be larger, and the macroscopic manifestation is a sticky state. The surface of the film coating formed is sticky, and the bottom of the coating is hard.

[0093] Polyurethane: Polyurethane is a polymer with a certain molecular weight obtained by the reaction of diols and diisocyanates. When the terminal group is hydroxy acrylate, the obtained polyurethane becomes acrylic polyurethane, i.e. PUA resin. Molecules containing active hydroxyl groups will undergo addition reaction with isocyanates.

[0094] As pointed out in the background technology section, PMMA waterproof coating is easily attacked by oxygen and may cause incomplete curing. The inventors of this application found in the process of improving the prior art that:

[0095] The saturated vapor pressure of MMA (methyl methacrylate) is relatively low, and the initiator speed is too fast, which will cause the MMA monomer to fail to react completely and remain in the coating, causing the MMA gas to be inhaled by the human body or have a certain impact on the environment.

[0096] The methods to solve oxygen inhibition in the prior art are generally to isolate or eliminate oxygen, specifically by covering a layer of film on the coating, introducing a sealant (such as wax) or an oxygen scavenger (such as mercapto) into the coating. However, these methods inevitably have the problem of poor environmental adaptability, and the humidity, temperature and cleanliness of the environment will have a great impact on the implementation of these methods.

[0097] Existing PMMA waterproof coatings are high-glass transition temperature coatings, which are used in locations with low base mobility, such as floors and railway tracks, and their application scenarios are limited. Because most buildings use concrete structures, concrete structures will shrink and settle during long-term negative pressure, that is, the base is highly mobile, which requires the coating covering the building surface to have a certain degree of elasticity and flexibility to prevent stress cracking and frost cracking. Therefore, it is necessary to improve PMMA waterproof coatings to make them have a wider range of applications.

[0098] In order to solve the problems existing in the prior art, the embodiments of the present application provide an air-drying prepolymer and a preparation method thereof, a PMMA elastic waterproof coating and a preparation method thereof, which are introduced one by one below.

[0099] PMMA elastic waterproof coating and preparation method thereof

[0100] The PMMA elastic waterproof coating comprises a component A and a component B; wherein, by weight, the component A comprises:

[0101] PUA resin, 100 parts by weight, where the PUA resin is the above-mentioned PUA resin or a PUA resin prepared according to the preparation method of the PUA resin;

[0102] 20 to 100 parts by weight of the air-drying prepolymer based on 100 parts by weight of the PUA resin is the above-mentioned air-drying prepolymer:

[0103] Based on 100 parts by weight of PUA resin, the active diluent is 40 to 250 parts by weight:

[0104] Based on 100 parts by weight of PUA resin, 50 to 225 parts by weight of powder:

[0105] 20 to 100 parts by weight of plasticizer based on 100 parts by weight of PUA resin:

[0106] 20 to 90 parts by weight of reinforcing agent based on 100 parts by weight of PUA resin:

[0107] 10 to 50 parts by weight of air drying agent based on 100 parts by weight of PUA resin:

[0108] 8 to 50 parts by weight of reducing agent based on 100 parts by weight of PUA resin:

[0109] 4 to 25 parts by weight of anti-settling agent based on 100 parts by weight of PUA resin:

[0110] 2 to 10 parts by weight of an anti-ultraviolet aging agent based on 100 parts by weight of PUA resin:

[0111] 2 to 10 parts by weight of antioxidant based on 100 parts by weight of PUA resin:

[0112] Component B is an oxidizing agent.

[0113] The PMMA elastic waterproof coating of the embodiment of the present application uses an air-drying prepolymer to mix with a PUA resin and other components in the PMMA elastic waterproof coating, introduces the air-drying prepolymer into the PUA resin, and then introduces it into the structure of the PMMA elastic waterproof coating. The air-drying prepolymer containing oxygen-absorbing functional groups has good storage stability, which can effectively reduce the influence of oxygen inhibition on the curing behavior of the PMMA elastic waterproof coating.

[0114] On the one hand, the PMMA elastic waterproof coating of the embodiment of the present application, through the click chemistry reaction of "free radical polymerization", the oxygen-absorbing functional group is made into a monomer structure with excellent storage stability, and the monomer structure containing the oxygen-absorbing functional group is polymerized with the PUA resin when forming the PMMA elastic waterproof coating and introduced into the PUA resin structure, thereby effectively reducing the effect of oxygen inhibition on the curing of the PMMA coating, improving the conversion rate of acrylate monomers containing double bonds, and improving the smoothness of the surface of the PMMA elastic waterproof coating film.

[0115] On the other hand, the PMMA elastic waterproof coating of the embodiment of the present application adjusts the molar ratio of -NCO in the polyisocyanate forming the PUA resin and -OH in the polyether polyol, that is, the R value, and forms a polyurethane structure with double bonds through hydroxy acrylate, which provides reaction sites for the subsequent reactive diluent monomer to form chain growth and three-dimensional network cross-linking structure on the molecular structure of the polyurethane, thereby obtaining a PMMA elastic waterproof coating with both strength and ductility, so as to be better suitable for various scenes. Such as ground structures and roof structures with a large degree of base activity. For example, it can be applied to scenes with a large degree of base activity such as parking lots with high activity intensity, metal bridge decks, and steel structure roofs.

[0116] The inventor of the present application has considered that during the construction process of PMMA elastic waterproof coating, the working conditions of electric mixers with high torque are usually not available, and the slurry needs to have a relatively long low viscosity working condition. Polar functional groups (side chains of end-capping agents have hydroxyl groups) and large steric hindrance functional groups (long chains and organic molecular chains of hydroxy acrylate monomers introduced into PUA resin) are introduced into the resin structure of PMMA elastic waterproof coating to reduce the viscosity of the resin and promote the floating of the air-drying agent, so as to form an oxygen barrier layer on the surface of PMMA elastic waterproof coating, further isolate PMMA elastic waterproof coating from oxygen in the air, and reduce the effect of oxygen inhibition on coating curing. And improve the surface dryness of PMMA elastic waterproof coating.

[0117] In some embodiments of the present application, the mass ratio of component A to component B is 100:(1-5).

[0118] In some embodiments of the present application, the powder is selected from heavy calcium carbonate, light calcium carbonate, talc, barium sulfate, aluminum hydroxide, titanium dioxide, fumed silica, nano calcium carbonate or a combination thereof.

[0119] In some embodiments of the present application, the particle size of the powder is 400 mesh to 2000 mesh.

[0120] In some embodiments of the present application, the reactive diluent is selected from methacrylic acid, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, styrene, isooctyl acrylate, glycidyl acrylate, hydroxyethyl methacrylate, ethyl acrylate or a combination thereof.

[0121] In the embodiments of the present application, by optimizing the monomer ratio of the acrylic acid active diluent, the adhesion of the PMMA elastic waterproof coating to the cement foundation is improved, while the pungent odor and residue of acrylic acid are further reduced, thereby reducing the impact on construction workers and the environment.

[0122] In the PMMA elastic waterproof coating of the embodiment of the present application, the air-drying prepolymer with oxygen-absorbing functional groups is obtained by a simple esterification reaction addition, and a part of the carboxyl group is retained. After the PMMA elastic waterproof coating is formed into a film, it can undergo a "carboxyl-epoxy" chemical reaction with the epoxy group of acrylic acid glycidyl ether in the active diluent to achieve cross-linking after film formation, further increase the internal cross-linking density, and effectively enhance the tensile modulus strength of the PMMA elastic waterproof coating.

[0123] In some embodiments of the present application, the air-drying agent is refined or semi-refined paraffin wax. Exemplarily, the air-drying agent is paraffin wax with a grade of 52#, 54#, 56#, 58#, 60#, 62#, or 68#.

[0124] In some embodiments of the present application, the anti-ultraviolet aging agent is selected from UV-326, UV-329 or a combination thereof.

[0125] In some embodiments of the present application, the antioxidant is selected from 1010, 686 or a combination thereof.

[0126] In some embodiments of the present application, the reducing agent is selected from diethanolamine, dimethylethanolamine, N,N-diethylhydroxylamine, N,N-dimethyl-p-toluidine, N,N-diethylaniline or a combination thereof.

[0127] In some embodiments of the present application, the anti-settling agent is selected from fumed silica, organic bentonite or polyurea anti-settling agent. For example, the anti-settling agent can be a thickening anti-settling agent with a brand name of A-200, the main component of which is fumed silica.

[0128] In some embodiments of the present application, the reinforcing agent is selected from 3102 Mitsubishi resin, 950 Mitsubishi resin or a combination thereof.

[0129] In some embodiments of the present application, the plasticizer is selected from acetyl tributyl citrate, dioctyl terephthalate (DOTP), dioctyl phthalate (DOP), or a combination thereof.

[0130] In some embodiments of the present application, the oxidizing agent is selected from benzoyl peroxide, cumene hydroperoxide or a combination thereof.

[0131] The inventors of this application found in the process of further improving the prior art that the existing PMMA waterproof coating realizes the self-polymerization reaction of MMA monomers through the redox reaction of oxidants and reductants. Since the oxidants and reductants are mixed in equal proportions in a molar equivalent ratio, a large number of free radicals will be generated at the moment of contact. Therefore, the PMMA waterproof coating can achieve condensation in 20 minutes and surface drying in 60 minutes, which can shorten the construction period to a limited extent. However, since the redox reaction is too rapid and the heat generation is huge, the huge heat generated will increase the volatilization of the monomers, and cause the environment to overheat, resulting in the risk of explosion, which may cause harm to the health and personal safety of the construction workers. Therefore, it is necessary to improve this. This application controls the reaction process through a thermally controllable method to achieve safe construction while ensuring that the coating can be cured.

[0132] In some embodiments of the present application, component A of the PMMA elastic waterproof coating further includes: 1 to 15 parts by weight of a pH buffer based on 100 parts by weight of the PUA resin.

[0133] In some embodiments of the present application, the pH buffer is selected from tartaric acid, potassium dihydrogen phosphate, sodium bicarbonate or a combination thereof.

[0134] The PMMA elastic waterproof coating of the embodiment of the present application optimizes the types and ratios of the oxidant and the reductant and creatively introduces a pH buffer to ensure the pH stability of the coating system, reduce the reaction heat during the reaction of the oxidant and the reductant, and achieve a high conversion rate of the acrylate monomers.

[0135] In some embodiments of the present application, component A of the low-odor, quick-drying PMMA elastic waterproof coating further includes: 2 to 10 parts by weight of color paste based on 100 parts by weight of PUA resin.

[0136] In some embodiments of the present application, the color paste is selected from emerald green, iron red, orange or a combination thereof, so that the PMMA elastic waterproof coating has a set color.

[0137] The preparation method of PMMA elastic waterproof coating comprises: dispersing PUA resin, powder, active diluent, air drying agent, plasticizer, anti-ultraviolet aging agent, antioxidant, reducing agent, anti-settling agent, reinforcing agent and air drying prepolymer according to the composition and content of PMMA elastic waterproof coating to obtain component A; and mixing component B with component A to obtain PMMA elastic waterproof coating.

[0138] In other embodiments of the present application, the method for preparing the PMMA elastic waterproof coating further includes: dispersing the pH buffer with other components in component A.

[0139] In other embodiments of the present application, the method for preparing the PMMA elastic waterproof coating further includes: dispersing the color paste with other components in component A.

[0140] In some embodiments of the present application, the pH buffer and the color paste are dispersed together with other components in component A. It should be noted that the other components in component A referred to herein refer to the components in component A except the pH buffer and / or the color paste.

[0141] In some embodiments of the present application, the preparation method of PMMA elastic waterproof coating comprises: according to the amount of each component in the PMMA elastic waterproof coating, 100 parts by weight of PUA resin is added to a high-speed disperser (shear speed is 4000rpm~10000rpm), and 50~225 parts by weight of powder is added for shear dispersion for 30 minutes to 50 minutes, and active diluent is added 2 to 3 times for shear dispersion for 1 hour to 2 hours, and air drying agent, color paste, pH buffer, plasticizer, anti-ultraviolet aging agent, antioxidant, reducing agent, anti-settling agent, reinforcing agent, and air drying prepolymer are added in sequence, and shear dispersion is carried out for 1 hour to 2 hours, and the material is discharged to obtain component A of PMMA elastic waterproof coating; component A and component B are dispersed to obtain PMMA elastic waterproof coating.

[0142] Air-drying prepolymer and preparation method thereof

[0143] The method for preparing an air-drying prepolymer comprises: providing compounds of structures represented by formula (9) to formula (11) respectively, using one or a combination of the compounds of structures represented by formula (9) to formula (10) as raw material A, and using a compound of structure represented by formula (11) as raw material B;

[0144]

[0145] In formula (9), R3 is H or methyl;

[0146]

[0147] In formula (10), R4 is H or methyl;

[0148]

[0149] In formula (11), R5 is H, C1-C8 alkyl, or C1-C8 alkyl substituted with hydroxyl, and R6 is C1-C8 alkylene;

[0150] Raw material A, raw material B, a solid acid catalyst and a polymerization inhibitor are mixed and reacted in a ratio of 1:(1-3):(0.01wt.%-0.06wt.%):(0.05wt.%-0.1wt.%) to obtain an air-drying prepolymer; wherein the raw material A and the raw material B are in a molar ratio, and the ratio of the solid acid catalyst and the polymerization inhibitor is calculated as a percentage of the total mass of the raw material A and the raw material B.

[0151] In some embodiments of the present application, the compound of the structure shown in formula (9) is nadic anhydride or methyl nadic anhydride, the compound of the structure shown in formula (10) is tetrahydrophthalic anhydride or methyl tetrahydrophthalic anhydride, and the compound of formula (11) is selected from hydroxyethyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, and hydroxybutyl methacrylate.

[0152] In some embodiments of the present application, the solid acid catalyst is selected from β molecular sieve, strong acid resin, sulfuric acid / zirconium oxide, and tungstic acid / zirconium oxide.

[0153] In some embodiments of the present application, the β molecular sieve refers to a high-silicon zeolite having a three-dimensional cross-structured twelve-membered ring channel, and the chemical composition is: |Na +7 |[Al7Si 57 O 128 ]-BEA, selected from NE-H00-02, NE-H00-04.

[0154] In some embodiments of the present application, the strong acid resin is selected from Rohm and Haas Amberlyst 15WET and D005 macroporous strong acid cationic resin.

[0155] In some embodiments of the present application, the polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone, methylhydroquinone or a combination thereof.

[0156] In some embodiments of the present application, a method for preparing an air-drying prepolymer comprises: providing a hydroxy acrylate monomer shown in formula (11), an inhibitor, and providing a composition of one or more of nadic anhydride, methyl nadic anhydride, tetrahydrophthalic anhydride, and methyltetrahydrophthalic anhydride; adding the composition of one or more of nadic anhydride, methyl nadic anhydride, tetrahydrophthalic anhydride, and methyltetrahydrophthalic anhydride to a mixture of the hydroxy acrylate monomer shown in formula (11) and the inhibitor under the catalysis of a solid acid catalyst, reacting at 130° C. to 135° C. and a vacuum degree of -0.03 MPa to -0.05 MPa for 3 hours to 4 hours, and discharging the material to obtain a novel air-drying prepolymer.

[0157] It should be noted that the method for preparing the air-drying prepolymer can be that the compound with the structure represented by formula (9) or formula (10) reacts alone with the compound with the structure represented by formula (11), or the compounds with the structures represented by formula (9) and formula (10) are mixed and reacted with the compound with the structure represented by formula (11) to obtain the air-drying prepolymer.

[0158] In an embodiment of the present application, a hydroxy acrylate compound of the structure shown in formula (11) is provided, and the hydroxy acrylate compound of the structure shown in formula (11) and a polymerization inhibitor are heated to 135° C. to 138° C. and vacuum-dehydrated for 2 to 3 hours to reduce the moisture content in the hydroxy acrylate compound of the structure shown in formula (11) to less than 0.5%. The polymerization inhibitor can slow down the reaction rate of the hydroxy acrylate monomer compound of the structure shown in formula (11) during the heating and vacuum-dehydration process to prevent the hydroxy acrylate monomer compound of the structure shown in formula (11) from solidifying prematurely.

[0159] According to the preparation method of the air-drying prepolymer of the embodiment of the present application, an air-drying prepolymer can be prepared, and the air-drying prepolymer includes one or a combination of compound structures represented by formula (1) to formula (4):

[0160]

[0161]

[0162] In formula (1) to formula (4), R1 is selected from C1-C8 alkylene, and R2 is selected from H, C1-C8 alkyl, and hydroxy-substituted C1-C8 alkyl.

[0163] In some embodiments of the present application, R1 is selected from methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, and octylene.

[0164] In some embodiments of the present application, R2 is selected from H, methyl, ethyl, propyl, butyl, pentyl, n-hexyl, n-heptyl, n-octyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, hydroxypentyl, hydroxyhexyl, hydroxyheptyl, and hydroxyoctyl.

[0165] In some embodiments of the present application, the compound of the structure shown in formula (1) includes:

[0166]

[0167] In some embodiments of the present application, the compound of the structure shown in formula (2) includes:

[0168]

[0169] In some embodiments of the present application, the compound of the structure shown in formula (3) includes:

[0170]

[0171] In some embodiments of the present application, the compound of the structure shown in formula (3) includes:

[0172]

[0173] Taking the compound represented by the structure of formula (9) as nadic anhydride and the compound represented by the structure of formula (11) as hydroxyethyl acrylate as an example, under the catalytic conditions of the solid acid catalyst, nadic anhydride and hydroxyethyl acrylate undergo the following reaction:

[0174]

[0175] Among them, since the molar ratio of hydroxyethyl acrylate and nadic anhydride is 1 to 3:1, when the hydroxyethyl acrylate monomer is not excessive (molar ratio is 1:1), the nadic anhydride mainly reacts to obtain an air-drying prepolymer with one acrylate double bond, and a very small amount of nadic anhydride will react to obtain an air-drying prepolymer with two acrylate double bonds. When the hydroxyethyl acrylate monomer is excessive (the molar ratio of hydroxyethyl acrylate and nadic anhydride is 1.1 to 3:1), the content of the air-drying prepolymer with two acrylate double bonds will increase. Similarly, the same situation also exists when methyl nadic anhydride, tetrahydrophthalic anhydride, and methyltetrahydrophthalic anhydride react with the compound of the structure shown in formula (11).

[0176] In the embodiments of the present application, nadic anhydride, methyl nadic anhydride, tetrahydrophthalic anhydride and methyltetrahydrophthalic anhydride are used to synthesize a new type of air-drying prepolymer, which can replace part of the acrylic monomers with a strong odor, reduce the odor of the PMMA elastic waterproof coating, and also introduce oxygen-absorbing functional groups into the resin structure of the final PMMA elastic waterproof coating, thereby reducing the effect of oxygen inhibition on its curing behavior.

[0177] In the embodiments of the present application, nadic anhydride, methyl nadic anhydride, tetrahydrophthalic anhydride, and methyl tetrahydrophthalic anhydride have similar structures, i.e., double-bond functional groups with oxygen absorption. Taking nadic anhydride as an example, the hydrogen on the positive carbon ion in its double bond is easily lost, becoming a free radical, combining with oxygen in the air to generate peroxide, and this peroxide will produce very strong free radicals, promoting the continuation of the next step of reaction, thereby a series of double-bond cross-linking reactions occur, effectively isolating the inhibition of oxygen on acrylate coatings, so that it solidifies in the air without becoming sticky. In addition, the air-drying prepolymer itself contains double bonds and can be used as a reactive diluent and cross-linking agent.

[0178] PUA resin and preparation method thereof

[0179] The preparation method of PUA resin comprises: providing polyether polyol and polyisocyanate, wherein the molar ratio R of -NCO in the polyisocyanate to -OH in the polyether polyol is 1.1-1.5; mixing the polyether polyol and the polyisocyanate to react to obtain a pre-finished product; adding an inhibitor, a capping agent, and a hydroxy acrylate compound to the pre-finished product in sequence under catalyst conditions to obtain a PUA resin; wherein, calculated based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate, the molar ratio of the inhibitor, the capping agent, and the hydroxy acrylate compound is 0.06:(0.1-0.5):1.

[0180] In an embodiment of the present application, the preparation method of the PUA resin further includes: mixing the PUA resin with an acrylate monomer to obtain a PUA resin diluent; wherein the amount of the acrylate monomer accounts for 20% to 40% of the total mass of the PUA resin. Exemplarily, the amount of the acrylate monomer can account for 25%, 28%, 30%, 32%, 35%, 36%, 38%, 40% of the total mass of the PUA resin.

[0181] In the embodiments of the present application, double-bond terminated polyurethane PUA with a relatively low R value (R value is 1.1-1.5) is used as the source of elasticity and flexibility of the PMMA elastic waterproof coating.

[0182] In some embodiments of the present application, providing the polyether polyol includes heating the polyether polyol to 103° C. to 108° C. and performing vacuum dehydration to reduce the water content of the polyether polyol to less than 0.5%.

[0183] In some embodiments of the present application, the molecular weight of the polyether polyol is in the range of 1000-6000, and the hydroxyl functionality is 2-3.

[0184] In an embodiment of the present application, the polyether polyol is selected from polyether diol, polyether triol or a combination thereof.

[0185] In some embodiments of the present application, the mass ratio of the polyether diol to the polyether triol is 1:(0.5-0.8).

[0186] In some embodiments of the present application, the polyether diol includes DL-2000D and / or DL1000D; the polyether triol includes EP330N and / or MN1000.

[0187] In some embodiments of the present application, the polyisocyanate is selected from toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI), or a combination thereof.

[0188] In some embodiments of the present application, in the polyisocyanate, TDI and HMDI, TDI and IPDI, MDI and HMDI, and MDI and IPDI are mixed and used, and the molar ratio thereof is 1:2-3.

[0189] In some embodiments of the present application, after the polyether polyol and the polyisocyanate react to obtain a prepolymer, a catalyst is used to catalyze the reaction of the capping agent and the hydroxy acrylate compound with the prepolymer.

[0190] In some embodiments of the present application, the catalyst is selected from dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dibutyltin didodecylsulfide, organic bismuth, organic zinc or a combination thereof.

[0191] In some embodiments of the present application, the amount of the catalyst used is 0.1 wt.% to 0.5 wt.% calculated as a mass percentage based on the total weight of the PUA resin product.

[0192] In some embodiments of the present application, the polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone, and methylhydroquinone.

[0193] In some embodiments of the present application, the capping agent is selected from benzyl alcohol, n-octanol, hydroxybutyric acid, isobornyl alcohol or a combination thereof.

[0194] In some embodiments of the present application, the hydroxyacrylate compound is selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate or a combination thereof.

[0195] In some embodiments of the present application, the acrylic acid ester monomer is selected from methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate or a combination thereof.

[0196] In an embodiment of the present application, a method for preparing a PUA resin comprises: putting a polyether polyol into a reactor, heating it to 103°C to 108°C for vacuum dehydration for 3 to 4 hours, testing the moisture content during the vacuum dehydration process to make the moisture content of the polyether polyol below 0.5%, and reducing the temperature of the polyether polyol to 70°C to 75°C; adding polyisocyanate to the polyether polyol cooled to 70°C to 75°C according to an R value of 1.1 to 1.5, reacting for 3 to 5 hours to obtain a pre-finished product; adding a catalyst to the pre-finished product, the amount of the catalyst added being 0.1wt.% to the mass percentage of the total weight of the PUA resin product. 0.5wt.%; under the catalytic condition of the catalyst, an inhibitor, a capping agent and a hydroxy acrylate compound are added to the pre-finished product in order, and after reacting at 70℃~75℃ for 2 hours to 3 hours, a PUA resin is obtained; wherein, based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate, the molar ratio of the inhibitor, the capping agent and the hydroxy acrylate compound is 0.06:(0.1~0.5):1; the PUA resin is cooled to 45℃~50℃, and an acrylate monomer is added to the PUA resin for dilution, the amount of the acrylate monomer accounts for 20%~40% of the total mass of the PUA resin, and the material is discharged to obtain a PUA resin dilution liquid.

[0197] The embodiments of the present application also provide a PUA resin, which is prepared according to the above-mentioned method for preparing the PUA resin.

[0198] Experimental Section

[0199] The following are the sources of some of the raw materials / reagents used in the examples.

[0200] Polyether polyol, brand: DL2000D, purchased from Bluestar Dongda Company;

[0201] Anti-settling agent, brand: A-200 thickening anti-settling agent, purchased from Arkema;

[0202] Reinforcing agent, brand: 3012 Mitsubishi resin, purchased from Mitsubishi Corporation;

[0203] The solid acid catalyst, brand: Amberlyst 15WET, was purchased from Rohm and Haas Company, USA.

[0204] Example 1

[0205] Synthesis of a New Air-Drying Prepolymer

[0206] 120 parts of hydroxyethyl acrylate and inhibitor hydroquinone were put into a reaction kettle, heated to 135°C, vacuumed and dehydrated for 3 hours, the moisture content of the test mixture was 0.2%, 165 parts of nadic anhydride and solid acid catalyst Rohm and Haas Amberlyst 15WET were slowly added, reacted for 3 hours at 130°C and vacuum degree of -0.03Mpa, and then discharged to obtain a novel air-drying prepolymer 1. Among them, the molar ratio of nadic anhydride: hydroxyethyl acrylate = 1:1, and the proportions of the solid acid catalyst and the inhibitor were calculated as a percentage of the total mass of raw material A and raw material B, which were 0.06wt.% and 0.1wt.%, respectively. Hydroxyethyl acrylate and nadic anhydride reacted as follows:

[0207]

[0208] Confirmation of air-drying prepolymer

[0209] In formula (12), the molecular weight of nadic anhydride is 164, the molecular weight of hydroxyethyl acrylate is 116, the molecular weight of nadic anhydride / hydroxyethyl acrylate monoadduct is 280, and the molecular weight of nadic anhydride / hydroxyethyl acrylate diadduct is 378.

[0210] like Figure 1 As shown, 3500cm -1 Corresponding to the characteristic peak of hydroxyl group, 2980cm -1 Corresponding to the characteristic peak of methyl group, 1727cm -1 Corresponding to the characteristic peak of carbonyl, 1636cm -1 Corresponding to the characteristic peak of the carbon-oxygen double bond in the ester group, 1411cm -1 Corresponding to the characteristic peak of methylene, 1186cm -1 This may correspond to the characteristic peak of CO in carboxylic acid, 810 cm -1 The characteristic peak corresponds to the CH characteristic peak on the carbon-carbon double bond. The characteristic peak corresponds to the functional group of the nadic anhydride / hydroxyethyl acrylate monoadduct or nadic anhydride / hydroxyethyl acrylate diadduct prepared in the present application, indicating that the nadic anhydride / hydroxyethyl acrylate monoadduct or nadic anhydride / hydroxyethyl acrylate diadduct was prepared in Example 1 of the present application.

[0211] like Figure 2As shown, in the HR-MS spectrum of the air-drying prepolymer prepared in Example 1, positions 256 and 282 correspond to nadic anhydride / hydroxyethyl acrylate monoadducts, and the intensities of these two positions are the highest, proving that nadic anhydride / hydroxyethyl acrylate monoadducts account for a large proportion. 336 may correspond to trimers formed by polymerization of hydroxyethyl acrylate during the reaction. Positions 318 and 320 may correspond to a "combination" of two nadic anhydrides bound together by strong hydrogen bonds. Positions 563 and 564 may correspond to a "combination" of two nadic anhydrides / hydroxyethyl acrylate monoadducts bound together by strong hydrogen bonds.

[0212] As shown in the following formula (13), Figure 3 The corresponding air-drying prepolymer prepared in Example 1 1 In the HNMR spectrum,

[0213]

[0214] exist Figure 3 The presence of characteristic peaks corresponding to different H in the structural molecular formula of formula (13) can prove that Example 1 of the present application prepared the nadic anhydride / hydroxyethyl acrylate monoadduct.

[0215] The above infrared absorption spectrum, HR-MS spectrum and 1 The HNMR spectrum can prove that the air-drying prepolymer prepared in Example 1 of the present application is a mixture of nadic anhydride / hydroxyethyl acrylate monoadduct and nadic anhydride / hydroxyethyl acrylate diadduct, and the air-drying prepolymer is mainly composed of nadic anhydride / hydroxyethyl acrylate monoadduct.

[0216] Synthesis of PUA resin

[0217] 1000 parts of polyether diol DL2000D were put into the reactor, heated to 105°C, vacuumed and dehydrated for 3 hours, and the temperature of the polyether diol was reduced to 75°C;

[0218] According to the ratio of R value of 1.1, 122 parts of polyisocyanate IPDI (isophorone diisocyanate) were added to the polyether diol at 75°C, and reacted for 3 hours to obtain a pre-finished product;

[0219] Add an organic tin catalyst dibutyltin dilaurate to the pre-finished product, the amount of the organic tin catalyst added is 0.1wt.% calculated as the mass percentage of the total weight of the PUA resin product; then add 0.2 parts of an inhibitor hydroquinone, 10 parts of a capping agent n-butanol, and 40 parts of a hydroxyacrylate compound hydroxyethyl acrylate in sequence, and react at 75°C for 2 hours to obtain PUA resin 1; cool the PUA resin 1 to 45°C, and add 300 parts of methyl methacrylate to the PUA resin 1 cooled to 45°C to obtain a diluted solution of PUA resin 1.

[0220] PMMA elastic waterproof coating and preparation method thereof

[0221] The PMMA elastic waterproof coating comprises: a component A and a component B with a mass ratio of 100:1; wherein the component A comprises:

[0222] PUA resin 1, 100 parts by weight; using methyl methacrylate accounting for 20% of the total weight of the PUA resin to dilute the PUA resin 1 to obtain a PUA resin 1 dilution;

[0223] Air-drying prepolymer 1, 20 parts by weight;

[0224] Reactive diluent methyl methacrylate, 100 parts by weight;

[0225] Powder, calcium carbonate, 50 parts by weight;

[0226] Plasticizer, chlorinated paraffin, 20 parts by weight;

[0227] Reinforcing agent, 3102 Mitsubishi resin, 20 parts by weight;

[0228] Air drying agent, paraffin, 10 parts by weight;

[0229] Reducing agent, N,N-dimethyl-p-toluidine, 8 parts by weight;

[0230] Anti-settling agent, fumed silica, 4 parts by weight;

[0231] Anti-ultraviolet aging agent, 2 parts by weight;

[0232] Antioxidant, 2 parts by weight;

[0233] pH buffer, 1 part by weight;

[0234] Composite green pulp, 1 part by weight;

[0235] Component B is the oxidant benzoyl peroxide (BPO), 3.4 parts.

[0236] Preparation method of PMMA elastic waterproof coating: according to the composition and weight proportion of PMMA elastic waterproof coating, add corresponding content of PUA resin 1 into high-speed disperser, put in powder and shear for 30 minutes, add active diluent 3 times, shear for 1 hour to disperse evenly, add air-drying agent, color paste, pH buffer, plasticizer, anti-ultraviolet aging agent, antioxidant, reducing agent, anti-settling agent, reinforcing agent, air-drying prepolymer 1 in sequence, shear for 1 hour to disperse evenly, discharge, and obtain component A of PMMA elastic waterproof coating; mix component B with component A to obtain PMMA elastic waterproof coating 1. The shearing speed is 4000rpm to 6000rpm.

[0237] Example 2

[0238] The PMMA elastic waterproof coating 2 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the content of the air-drying prepolymer 1 is 35 parts by weight.

[0239] Example 3

[0240] The PMMA elastic waterproof coating 3 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the content of the air-drying prepolymer 1 is 50 parts by weight.

[0241] Example 4

[0242] PMMA elastic waterproof coating 4 is different from PMMA elastic waterproof coating 1 of Example 1 in that PMMA elastic coating 4 is prepared by using air-drying prepolymer 2. The difference between air-drying prepolymer 2 and air-drying prepolymer 1 is that only the molar ratio of nadic anhydride to hydroxyethyl acrylate is 1:2.

[0243] Example 5

[0244] The PMMA elastic waterproof coating 5 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the PMMA elastic waterproof coating 5 is prepared using PUA resin 2. The difference between PUA resin 2 and PUA resin 1 is that the R value during the preparation of PUA resin 2 is 1.5.

[0245] Example 6

[0246] The PMMA elastic waterproof coating 6 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the amount of the active diluent used is 180 parts by weight.

[0247] Example 7

[0248] The PMMA elastic waterproof coating 7 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the active diluent comprises methyl methacrylate and butyl methacrylate in a mass ratio of 1:1.

[0249] Example 8

[0250] The PMMA elastic waterproof coating 8 is different from the PMMA elastic waterproof coating 1 of Example 1 in that the PMMA elastic waterproof coating is prepared using PUA resin 3. The difference between PUA resin 3 and PUA resin 1 is that, during the preparation of PUA resin 3, the methyl methacrylate used in the preparation of PUA resin 1 is replaced with methyl methacrylate and glycidyl acrylate in a mass ratio of 2:1.

[0251] Example 9

[0252] The PMMA elastic waterproof coating 9 is different from the PMMA elastic waterproof coating 1 of Example 1 in that no pH buffer is added.

[0253] Comparative Example 1

[0254] The PMMA elastic waterproof coating 10 is different from the PMMA elastic waterproof coating 1 of the embodiment in that the air-drying prepolymer 1 is not added.

[0255] Comparative Example 2

[0256] The PMMA elastic waterproof coating 10 is different from the PMMA elastic waterproof coating 1 of the embodiment in that the PMMA elastic coating 10 is prepared by using PUA resin 4. The difference between PUA resin 4 and PUA resin 1 is that the R value is 0.8.

[0257] Comparative Example 3

[0258] The PMMA elastic waterproof coating 12 is different from the PMMA elastic waterproof coating 1 of the embodiment in that the PMMA elastic coating 12 is prepared using PUA resin 6. The difference between PUA resin 6 and PUA resin 1 is that when preparing PUA resin 6, the molar ratio of -NCO in isophorone diisocyanate to -OH in polyether diol is 2:1.

[0259] Comparative Example 4

[0260] The PMMA elastic waterproof coating 12 is different from the PMMA elastic waterproof coating 1 in the embodiment in that in the step of preparing the air-drying prepolymer 1, an equal amount of nadic anhydride is replaced by maleic anhydride.

[0261] Comparative Example 5

[0262] The PMMA elastic coating with the brand / model GCP ELIMINATOR was purchased through commercial channels.

[0263] Performance Testing

[0264] The following performance tests were performed on the PMMA elastic coatings of Examples 1-9 and Comparative Examples 1-5:

[0265] 1. The surface drying time and the actual drying time are tested according to the test standard of GB / T19250-2013 to obtain the surface drying time t1 and the actual drying time t2, in minutes / min.

[0266] 2. The elongation at break test, tensile strength test and tear strength test shall be carried out in accordance with the test standards in GB / T19250-2013.

[0267] 3. For solid content test, refer to 7.5 of JC / T2251-2014.

[0268] 4. Surface smoothness test: The film-to-film method in GB / T 10006-2021 is adopted, and the smoothness is characterized by the test value of the coating friction coefficient.

[0269] 5. Surface reaction heat test: Mix the materials according to the ratio recommended by the manufacturer. Figure 4 As shown, pour 100g of the mixed material into the metal inner cylinder, put it into the insulation rack, cover it with the insulation cover, and gently touch the liquid surface with the thermometer probe. Connect the temperature display (start from the contact of each component material, and complete the above actions within five minutes). Record the temperature value every five minutes, record continuously for 60 minutes, draw a temperature change curve, and obtain the temperature extreme value and the time of occurrence. And record the test results in the following Table 1:

[0270] Table 1

[0271]

[0272] Note: The higher the solid content in Table 1, the less the MMA monomer volatilization. The smaller the value of the coating friction coefficient, the smoother the surface of the PMMA elastic coating. In the surface reaction heat test, "55℃ / 20min" indicates that the reaction temperature extreme value of 55℃ appears in 20 minutes.

[0273] From Table 1, we can conclude that:

[0274] 1. By comparing the test results of Examples 1-3, it can be concluded that with the increase in the amount of air-drying prepolymer added, the solid content of the PMMA elastic waterproof coating increases from 97% to 99%, indicating that the volatile components are reduced and the coating properties of the prepared PMMA elastic waterproof coating are comprehensively improved.

[0275] 2. The friction coefficients of the PMMA elastic waterproof coating films of Examples 1-8 are all ≤0.9, which are generally smaller than the friction coefficients of the coating films of the comparative examples of 0.8 to 1.15, indicating that the well-cured coating films of the PMMA elastic waterproof coating of the present application have a lower static friction coefficient.

[0276] 3. Comparing Examples 1-8 and Example 9, the surface reaction heat test of the PMMA elastic waterproof coating without adding the pH buffer in Example 9 has an extreme value of 60°C; while the surface reaction heat test of the PMMA elastic waterproof coating with the addition of the pH buffer has an extreme value of 56°C, which is significantly lower than 60°C. This indicates that during the curing process of the PMMA elastic waterproof coating, the addition of the pH buffer helps to control the curing speed, delay the exothermic peak and reduce the temperature rise, which helps to complete the curing.

[0277] 4. Comparing Example 1, Example 5 with Comparative Example 2 and Comparative Example 3, the R value is small, and the tear strength and tensile strength of the material after the PMMA elastic waterproof coating is formed into a film are poor; as the R value increases, the tear strength and tensile strength of the PMMA elastic waterproof coating are significantly increased, indicating that the stiffness of the material after the PMMA elastic waterproof coating is formed into a film increases, the elongation decreases, and the cost increases. Comparative Example 4 proves that when R is large, the tear strength and tensile strength of the material after the PMMA elastic waterproof coating is formed into a film increases, but the elongation at break is significantly reduced. Therefore, it is necessary to control the size of the R value as appropriate.

[0278] 5. Comparing Example 1 and Example 4, when the molar ratio of nadic anhydride to hydroxyethyl acrylate is reduced from 1:1 to 1:2, that is, the molar number of hydroxyethyl acrylate is greater than the molar number of nadic anhydride, the tear strength, elongation at break and tensile strength of the PMMA elastic waterproof coating are increased.

[0279] 6. Comparing Example 1, Example 6, Example 7 and Example 8, with the increase of the amount of active diluent, the tear strength and tensile strength of the PMMA elastic waterproof coating can be effectively improved, but the elongation at break will be reduced. Replacing methyl methacrylate with methyl methacrylate and butyl methacrylate in a mass ratio of 1:1 can effectively improve the elongation at break and tensile strength of the PMMA elastic waterproof coating. Replacing methyl methacrylate with methyl methacrylate and glycidyl acrylate in a mass ratio of 2:1 can effectively improve the elongation at break of the PMMA elastic waterproof coating.

[0280] 7. Comparative Example 1 proves that if no air-drying prepolymer is added, the solid content is low and the elongation at break of the PMMA elastic waterproof coating after film formation is poor. The solid content, tear strength, elongation at break and tensile strength of the PMMA elastic waterproof coating containing maleic anhydride in Comparative Example 4 and the commercially available elastic coating in Comparative Example 5 are significantly lower than those of the PMMA elastic waterproof coating in the examples of the present application.

[0281] The above is only a specific implementation method of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application.

Claims

1. A PMMA elastic waterproof coating, characterized in that: include: A component and a component B in a mass ratio of 100:(1-5); wherein, in parts by weight, component A includes: PUA resin, 100 parts by weight; the PUA resin is prepared from polyether polyol, polyisocyanate, end-capping agent, and hydroxy acrylate compound; wherein the molar ratio R of -NCO in the polyisocyanate to -OH in the polyether polyol is 1.1-1.5, and the molar ratio of the end-capping agent to the hydroxy acrylate compound is (0.1-0.5):1, calculated based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate; 20 to 100 parts by weight of an air-drying prepolymer based on 100 parts by weight of PUA resin, wherein the air-drying prepolymer comprises one or a combination of the compound structures represented by formula (1) to formula (4): （1）， （2）， （3）， （4）， In formula (1) to formula (4), R1 is selected from C1-C8 alkylene, and R2 is selected from H, C1-C8 alkyl, and hydroxy-substituted C1-C8 alkyl: 40 to 250 parts by weight of an active diluent based on 100 parts by weight of the PUA resin: the active diluent is selected from methacrylic acid, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, styrene, isooctyl acrylate, glycidyl acrylate, hydroxyethyl methacrylate, ethyl acrylate or a combination thereof; Based on 100 parts by weight of PUA resin, 50 to 225 parts by weight of powder: 20 to 100 parts by weight of a plasticizer based on 100 parts by weight of the PUA resin: the plasticizer is selected from acetyl tributyl citrate, dioctyl terephthalate, dioctyl phthalate or a combination thereof; 20 to 90 parts by weight of reinforcing agent based on 100 parts by weight of PUA resin: 10 to 50 parts by weight of air drying agent based on 100 parts by weight of PUA resin: 8 to 50 parts by weight of reducing agent based on 100 parts by weight of PUA resin: 4 to 25 parts by weight of anti-settling agent based on 100 parts by weight of PUA resin: 2 to 10 parts by weight of an anti-ultraviolet aging agent based on 100 parts by weight of PUA resin: 2 to 10 parts by weight of antioxidant based on 100 parts by weight of PUA resin: Component B is an oxidizing agent.

2. The PMMA elastic waterproof coating according to claim 1, characterized in that: The PUA resin is diluted with an acrylate monomer, and the amount of the acrylate monomer accounts for 20% to 40% of the total mass of the PUA resin; and / or The powder is selected from heavy calcium carbonate, light calcium carbonate, talcum powder, barium sulfate, aluminum hydroxide, titanium dioxide, fumed silica, nano calcium carbonate or a combination thereof; and / or The air-drying agent is refined or semi-refined paraffin; and / or The anti-ultraviolet aging agent is selected from RIASORB® UV-326, RIASORB® UV-329 or a combination thereof; and / or The antioxidant is selected from RIANOX® 1010, RIANOX® 686 or a combination thereof; The reducing agent is selected from diethanolamine, dimethylethanolamine, N,N-diethylhydroxylamine, N,N-dimethyl-p-toluidine, N,N-diethylaniline or a combination thereof; and / or The anti-settling agent is selected from fumed silica, organic bentonite or polyurea anti-settling agent; and / or The reinforcing agent is selected from 3102 Mitsubishi resin, 950 Mitsubishi resin or a combination thereof; and / or The oxidizing agent is selected from benzoyl peroxide, cumene hydroperoxide or a combination thereof.

3. The PMMA elastic waterproof coating according to claim 1, characterized in that: The preparation method of the PUA resin comprises: Providing a polyether polyol and a polyisocyanate, wherein the molar ratio R of -NCO in the polyisocyanate to -OH in the polyether polyol is 1.1 to 1.5; The polyether polyol and the polyisocyanate are mixed and reacted to obtain a pre-finished product; Under catalyst conditions, an inhibitor, a capping agent, and a hydroxy acrylate compound are sequentially added to the pre-finished product to obtain a PUA resin; wherein, based on the amount of -NCO remaining in the polyisocyanate after the reaction of the polyether polyol and the polyisocyanate, the molar ratio of the inhibitor, the capping agent, and the hydroxy acrylate compound is 0.06:(0.1-0.5):1; or The PUA resin is mixed with an acrylate monomer to obtain a PUA resin dilution solution; wherein the amount of the acrylate monomer accounts for 20% to 40% of the total mass of the PUA resin.

4. The PMMA elastic waterproof coating according to claim 3, characterized in that: The molecular weight of the polyether polyol is in the range of 1000 to 6000, and the hydroxyl functionality is 2 to 3; or The polyether polyol meets at least one of the following requirements: The polyether polyol is selected from polyether diol, polyether triol or a combination thereof; The mass ratio of the polyether diol to the polyether triol is 1:(0.5-0.8); The polyether diol includes DL-2000D and / or DL1000D; the polyether triol includes EP330N and / or MN1000; and / or The polyisocyanate is selected from toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate or a combination thereof; and / or Among the polyisocyanates, toluene diisocyanate and dicyclohexylmethane diisocyanate, toluene diisocyanate and isophorone diisocyanate, diphenylmethane diisocyanate and dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate and isophorone diisocyanate can be mixed in groups and used, and the molar ratio thereof is 1:2-3; and / or The catalyst is selected from dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dibutyltin didodecylsulfide, organic bismuth, organic zinc bismuth or a combination thereof; and / or The amount of the catalyst used is 0.1wt.% to 0.5wt.% calculated as a mass percentage of the total weight of the PUA resin product; and / or The end-capping agent is selected from benzyl alcohol, n-octanol, hydroxybutyric acid, isobornyl alcohol or a combination thereof; The hydroxy acrylate compound is selected from hydroxyethyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate or a combination thereof; and / or The acrylic acid ester monomer is selected from methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate or a combination thereof; and / or The polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone and methylhydroquinone.

5. The PMMA elastic waterproof coating according to any one of claims 1 to 4, characterized in that: The component A further comprises: 1 to 15 parts by weight of a pH buffer based on 100 parts by weight of the PUA resin; and / or The component A also includes: 2 to 10 parts by weight of color paste based on 100 parts by weight of PUA resin.

6. The PMMA elastic waterproof coating according to claim 5, characterized in that: The pH buffer is selected from tartaric acid, potassium dihydrogen phosphate, sodium bicarbonate or a combination thereof; and / or The color paste is selected from emerald green, iron red, orange or a combination thereof.

7. The PMMA elastic waterproof coating according to claim 1, characterized in that: In the formulae (1) to (4), R1 is selected from methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, and / or In the formulae (1) to (4), R2 is selected from H, methyl, ethyl, propyl, butyl, pentyl, n-hexyl, n-heptyl, n-octyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, hydroxypentyl, hydroxyhexyl, hydroxyheptyl, and hydroxyoctyl.

8. The PMMA elastic waterproof coating according to claim 1 or 7, characterized in that: The compound having the structure shown in formula (1) includes: (5); and / or The compound represented by the formula (2) includes: (6); and / or The compound represented by the formula (3) includes: (7); and / or The compound represented by the formula (4) includes: （8）。 9. The PMMA elastic waterproof coating according to claim 1, characterized in that: The method for preparing the air-drying prepolymer comprises: providing compounds having structures represented by formula (9) to formula (11) respectively, using one or a combination of the compounds having structures represented by formula (9) to formula (10) as raw material A, and using the compound having structure represented by formula (11) as raw material B: （9）， In formula (9), R3 is H or methyl; （10）， In formula (10), R4 is H or methyl; （11）， In formula (11), R5 is H, C1-C8 alkyl, or C1-C8 alkyl substituted with hydroxyl, and R6 is C1-C8 alkylene; The raw material A, the raw material B, the solid acid catalyst and the polymerization inhibitor are mixed and reacted in a ratio of 1:(1-3):(0.01wt.%-0.06wt.%):(0.05wt.%-0.1wt.%) to obtain an air-drying prepolymer; wherein the raw material A and the raw material B are in a molar ratio, and the ratio of the solid acid catalyst and the polymerization inhibitor is calculated as a percentage of the total mass of the raw material A and the raw material B.

10. The PMMA elastic waterproof coating according to claim 9, characterized in that: The compound represented by the formula (9) is nadic anhydride or methyl nadic anhydride; and / or The compound represented by the formula (10) is tetrahydrophthalic anhydride or methyltetrahydrophthalic anhydride; and / or The compound represented by formula (11) is selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate; and / or The solid acid catalyst is selected from beta molecular sieve, strong acid resin, sulfuric acid / zirconium oxide, tungstic acid / zirconium oxide; and / or The polymerization inhibitor is selected from hydroquinone, 2,5-di-tert-butylhydroquinone, methylhydroquinone or a combination thereof.

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