Waterproof paint, preparation method and coating

Abstract

The invention provides a waterproof coating, a preparation method and a coating. The waterproof coating is prepared from the following raw materials: silane modified polyurethane resin; a silane modified anti-UV nano filler; the silane-modified anti-UV nano-filler comprises silane-modified polyurethane resin and a silane-modified anti-UV nano-filler, the silane-modified polyurethane resin is obtained through a reaction of silane-modified composite isocyanate and polyether polyol, and the silane-modified polyurethane resin and the silane-modified anti-UV nano-filler have silane groups, epoxy groups, vinyl groups and optional ureido groups.

Description

Technical Field

[0001] The present disclosure relates to the field of chemical materials, and in particular to a waterproof coating, a preparation method and a coating. Background Art

[0002] Traditional polyurethane waterproof coatings have excellent mechanical properties and good waterproof performance, but poor weather resistance, easy to blister in high temperature and high humidity environments, high requirements for substrate dryness, and may contain free isocyanates that are harmful to the human body; acrylic waterproof coatings have good weather resistance and environmental protection, but the water resistance of the coating is poor, and it is difficult to construct under low temperature and high humidity conditions; JS waterproof coatings are easy to bond with wet bases and are easy to construct, but there is also the problem of difficult construction at low temperatures. With the improvement of the quality of life, people have higher and higher requirements for environmental protection. Therefore, the market needs low-odor, solvent-free, environmentally friendly high-performance waterproof coatings.

[0003] Silane-modified polymer is a new type of polymer material, which is usually divided into two categories: silane-modified polyether and silane-modified polyurethane. The main chain of the polymer is a macromolecular polyether or polyurethane prepolymer, which is end-capped with isocyanate silane or aminosilane. Its curing mechanism is moisture curing, which reacts with external moisture to produce a cross-linked network structure. Adhesives or coatings prepared based on silane-modified polymer resins have the comprehensive properties of silicone and polyurethane. Although conventional silane-modified resin coatings have their own unique physical properties, they also have certain disadvantages. For example, their adhesion to concrete is relatively low, and a special primer is required to treat the base layer to achieve a firm bond. In addition, the large amount of plasticizer added makes the material easy to migrate, causing the material to age and deteriorate, and easy to crack.

[0004] Therefore, the current waterproof coatings still need to be further improved. Summary of the invention

[0005] The present disclosure aims to provide a waterproof coating, a preparation method and a coating to solve or alleviate one or more technical problems in the related art.

[0006] As a first aspect of an embodiment of the present disclosure, the present disclosure provides a waterproof coating. The raw materials for forming the waterproof coating include:

[0007] Silane modified polyurethane resin;

[0008] Silane modified UV resistant nanofillers; and

[0009] additive,

[0010] The silane-modified polyurethane resin is obtained by reacting a silane-modified complex isocyanate and a polyether polyol, and the silane-modified polyurethane resin and the silane-modified anti-UV nanofiller contain a silane group, an epoxy group, a vinyl group, and optionally a urea group.

[0011] Furthermore, the silane-modified polyurethane resin and the silane-modified anti-UV nanofiller are obtained by modification with a modifier, wherein the modifier includes a silane coupling agent, and the silane coupling agent includes any one or more of WD50, KH550, KH560, KH570, and IPST.

[0012] Furthermore, the silane coupling agent includes multiple coupling agents.

[0013] Furthermore, the mass ratio of isocyanate to the silane coupling agent in the raw material for forming the composite isocyanate is (7-10): (0.8-2).

[0014] Furthermore, the raw materials for forming the waterproof coating further include hydrolysis coupling gel, and the hydrolysis coupling gel is formed by hydrolysis reaction of multiple silane coupling agents.

[0015] Furthermore, the silane-modified anti-UV nanofiller is formed of nanoparticles and a modifier, the nanoparticles include at least one of titanium dioxide, cerium oxide, zinc oxide, tungsten oxide, silicon oxide and vanadium oxide, and the modifier includes a variety of silane coupling agents.

[0016] Furthermore, the additive comprises a composite anti-sagging agent thixotropic paste, and optionally at least one of a dewatering agent, a catalyst, a dispersant, a defoaming agent and a filler, wherein the composite anti-sagging agent thixotropic paste comprises nano calcium, gas silica, wax powder and bentonite.

[0017] Furthermore, in the raw materials for forming the silane-modified polyurethane resin, the mass ratio of the complex isocyanate and the polyether polyol is (3-8): (15-30).

[0018] Furthermore, the waterproof coating satisfies at least one of the following conditions:

[0019] The viscosity of the waterproof coating is 11500-16400 mPa.s;

[0020] The volatile organic compound content of the waterproof coating is not higher than 20g / L.

[0021] In another aspect of the present disclosure, the present disclosure provides a method for preparing the aforementioned waterproof coating. The method comprises:

[0022] Forming a composite isocyanate, wherein the composite isocyanate is formed by reacting an isocyanate and a modifier containing a silane at a temperature not higher than 20 degrees Celsius;

[0023] Forming a silane-modified polyurethane resin, wherein the silane-modified polyurethane resin is formed by adding the complex isocyanate to a polyether polyol;

[0024] forming a silane-modified anti-UV nanofiller, wherein the modified anti-UV nanofiller is obtained by treating nanoparticles with the modifier,

[0025] The silane-modified polyurethane resin, the silane-modified anti-UV nanofiller and the additive are mixed and subjected to a degassing treatment to obtain the waterproof coating.

[0026] Further, the method satisfies at least one of the following conditions:

[0027] When forming the composite isocyanate, the isocyanate and the first modifier are added to cold water and the temperature is maintained at no more than 20 degrees Celsius, and then the second modifier to the fourth modifier are sequentially added dropwise, and each is independently reacted for 0.5-1.5 hours and the temperature is controlled to be no more than 20 degrees Celsius, and the mass ratio of the isocyanate, the first modifier, the second modifier, the third modifier and the fourth modifier is (8-10): (0.3-0.8): (0.05-0.2): (0.1-0.3): (0.2-0.5);

[0028] When forming the silane-modified polyurethane resin, the polyether polyol is subjected to a temperature-raising dehydration treatment to make its moisture content no higher than 0.05%, and then the composite isocyanate is added to the polyether polyol to react until the isocyanate group content is 0;

[0029] The additive comprises a composite anti-sagging agent thixotropic paste, and the composite anti-sagging agent thixotropic paste is obtained by physically mixing nano calcium, gas silicon, wax powder and bentonite.

[0030] The method further comprises an operation of forming a hydrolyzed coupling agent gel, wherein the operation of forming the hydrolyzed coupling agent gel comprises mixing and stirring a plurality of silane coupling agents and water in a closed container to perform a hydrolysis reaction.

[0031] Furthermore, when forming the silane-modified polyurethane resin, it further includes: after adding the complex isocyanate to the polyether polyol to react until the isocyanate group content is 0, adding the hydrolysis coupling agent gel to react for 20-120 minutes.

[0032] In another aspect of the present disclosure, the present disclosure provides a coating, which is formed by using the above-mentioned waterproof coating.

[0033] The waterproof coating and preparation method thereof proposed in the present disclosure adopt silane-modified polyurethane resin, silane-modified anti-UV nanofiller, and a suitable additive system to prepare a new type of silane-modified single-component moisture-curing waterproof coating. The waterproof coating reacts with water vapor in the air to form a silicon-oxygen-silicon three-dimensional cross-linked structure. When used, it is coated on the base layer and cured by reacting with moisture to form a continuous and seamless polymer elastic waterproof film. In addition, the waterproof coating has excellent long-lasting adhesion to various base layers and has large cohesive energy. The material has excellent tensile properties, greatly improved water resistance, and fast drying at low temperature.

[0034] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present disclosure will be readily apparent from the following detailed description. DETAILED DESCRIPTION

[0035] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present disclosure, and different embodiments may be combined arbitrarily without conflict. Therefore, the following description is considered to be illustrative and non-restrictive in nature.

[0036] In the first aspect of the present disclosure, the present disclosure proposes a waterproof coating. The raw materials for forming the waterproof coating include silane-modified polyurethane resin, silane-modified anti-UV nanofiller and additives. The silane-modified polyurethane resin is obtained by reacting a silane-modified complex isocyanate and a polyether polyol, and the silane-modified polyurethane resin and the silane-modified anti-UV nanofiller have a silane group, an epoxy group, a vinyl group, and optionally a urea group. The waterproof coating has at least one of the advantages of being solvent-free, safe and environmentally friendly, fast curing speed, fast drying at particularly low temperatures, having a greater wetting ability for the base layer, strong adhesion, and good bonding to various substrates.

[0037] For ease of understanding, the following is a brief description of the principle by which the coating can achieve the aforementioned beneficial effects:

[0038] Most of the existing polyurethane waterproof coatings on the market are easy to produce carbon dioxide gas when reacting with air, and it is difficult to bond to a wet base surface. The solid content is generally low, and it contains a large amount of solvents. It is a non-exposed coating and has poor weather resistance. Although the above problems are also improved by forming a resin coating through silane modification in the related art, the silane-modified resin coating often has poor weather resistance, and the lasting adhesion to the base layer such as concrete is not high. A special primer is required to treat the base layer to achieve a firm bond. In addition, a large amount of plasticizer is added, which is easy to seep out, and the material ages quickly and is easy to crack. Therefore, the performance of the waterproof coating obtained cannot be effectively controlled. Generally, there are problems such as low physical properties, high viscosity, and viscosity reduction by adding a diluent, poor bonding to the base layer, especially poor bonding to the concrete base layer, poor bonding to the wet base surface, and insufficient water resistance.

[0039] The present invention adopts silane-modified polyurethane resin and silane-modified anti-UV nanofiller to form waterproof coating, and can obtain coating with good water resistance, weather resistance, oxidation resistance, air permeability, low polarity and low surface performance through silane modification. In addition, due to the relatively low compatibility of silicone and polyurethane, siloxane will migrate to the surface of the film and enrich on the surface of the polyurethane film, which can give the modified polymer low surface energy and improve the water resistance, chemical resistance, high and low temperature resistance, weather resistance and other properties of the paint film. The silicone material is mixed with physical methods to reduce the surface performance of the coating film and improve the overall performance.

[0040] In the waterproof coating disclosed in the present invention, the silane-modified polyurethane resin and the silane-modified anti-UV nanofiller are obtained by modification treatment with a modifier. The modifier contains at least one of a silane group, an epoxy group, and a vinyl group. The modifier can react with the raw material isocyanate in the polyurethane resin to generate a urea group. The above groups are conducive to the coating forming a moderate viscosity and maintaining a high solid content. In addition, the silane-modified group is also conducive to improving the weather resistance and mechanical properties of the coating formed by the coating due to the aforementioned migration and enrichment process.

[0041] In addition, the waterproof coating proposed in the present disclosure can be used as both a waterproof layer and a bonding layer, so that the modified asphalt roll or thermoplastic polyolefin (TPO) waterproof roll can be firmly bonded to the base layer or roll, and the system can be cold-bonded. It is also suitable for bonding construction of polystyrene board (EPS) and extruded board (XPS) insulation board, and has good flexibility in low temperature environment and can adapt to the temperature difference between hot and cold.

[0042] According to some examples of the present invention, the aforementioned modifier includes a silane coupling agent. The specific type of the silane coupling agent is not particularly limited, for example, it can include any one or more of WD50, KH550, KH560, KH570, and IPST. In some examples, the modifier may include two or more of the above-mentioned silane coupling agents.

[0043] According to some examples of the present invention, the composite isocyanate can be obtained by reacting isocyanate with a silane coupling agent in advance, wherein the isocyanate includes a compound containing an isocyanate group, for example, including but not limited to one or more of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI), and dicyclohexylmethane diisocyanate (HMDI). The mass ratio of isocyanate to the silane coupling agent in the raw material for forming the composite isocyanate can be (7-10): (0.8-2). The above ratio is conducive to the formation of isocyanate fully modified by the silane modifier, and the content and ratio of urea group, epoxy group, unsaturated group and silane group in the obtained composite isocyanate are all moderate, which is conducive to the formation of a silane-modified polyurethane resin with good polymerization degree, viscosity and network structure. More specifically, a variety of silane coupling agents may be used in this step, such as IPTS, KH550, KH560 and KH570, wherein the mass ratio of IPTS:KH550:KH560:KH570 may be (0.3-0.8):(0.05-0.2):(0.1-0.3):(0.2-0.5).

[0044] In the raw materials of the silane-modified polyurethane resin, the mass ratio of the complex isocyanate to the polyether polyol is not particularly limited, and can be, for example, (3-8):(15-30).

[0045] In some examples of the present invention, the raw materials for forming the waterproof coating may further include a hydrolysis coupling gel. The hydrolysis coupling gel is formed by a hydrolysis reaction of multiple silane coupling agents, and the ratio of silane coupling agent to water may be (500-700):1. In other words, the raw materials of the waterproof coating may contain a gel system formed by a silane coupling agent and water. Pre-forming a part of the silane coupling agent and water to form a gel is beneficial to reducing the reaction rate of the system and preventing the formation of components with excessive molecular weight, which leads to a decrease in the overall viscosity of the system. The hydrolysis coupling agent gel may contain multiple silane coupling agents, for example, KH550, KH560, and KH570, wherein the mass ratio of KH550:KH560:KH570 may be (0.5-2):(1-3):(2-5). In a specific embodiment, the mass ratio of KH550:KH560:KH570:water may be 1:2:3:0.01.

[0046] The hydrolysis coupling gel can be added in the step of forming the silane-modified polyurethane resin, and the content of the added hydrolysis coupling gel is not particularly limited. However, in a specific embodiment, in order to further improve the performance of the coating, the mass ratio of the composite isocyanate, the polyether polyol and the hydrolysis coupling gel in the raw materials of the silane-modified polyurethane resin can be (3-8): (15-30): (0.1-0.5).

[0047] In some examples of the present invention, silane-modified anti-UV nanofillers can be formed by nanoparticles and modifiers. In the present invention, the specific types of nanoparticles are not particularly limited, as long as they have certain anti-UV properties. For example, the nanoparticles may include at least one of titanium dioxide, cerium oxide, zinc oxide, tungsten oxide, silicon oxide and vanadium oxide, and the particle size of the nanoparticles is preferably 20-100nm, and the modifier includes a variety of silane coupling agents. The modifier here can be selected from the aforementioned silane coupling agents. The silane modifier forming the silane-modified anti-UV nanofiller may be the same as the modifier forming the composite isocyanate, or it may be different. In the silane-modified anti-UV nanofiller, the mass ratio of nanoparticles and modifiers can be (8-12): (0.03-0.1).

[0048] In order to further improve the performance of the coating, the raw materials for forming the waterproof coating may further include one or more additives. For example, the additives include a composite anti-sagging agent thixotropic paste, and optionally at least one of a dewatering agent, a catalyst, a dispersant, a defoaming agent, and a filler. The specific composition of the dewatering agent, the catalyst, the dispersant, the defoaming agent, the filler, etc. is not particularly limited, and those skilled in the art can select according to actual needs.

[0049] According to an embodiment of the present invention, a composite anti-sagging agent thixotropic paste includes nano calcium, gas silicon, wax powder and bentonite. The composite anti-sagging agent thixotropic paste of the above components is particularly suitable for a polyurethane resin system modified by silane. Specifically, nano calcium and gas silicon are conducive to forming more hydrogen bonds in the system, thereby constructing a three-dimensional network structure to improve the mechanical properties and weather resistance of the coating formed by the coating. Moreover, the above two components have good silane affinity, which is conducive to forming a more uniform system. In addition, bentonite can enhance the water resistance, strength and adhesion of the coating, and wax powder has the effect of increasing the storage stability of the coating, which is conducive to forming a more three-dimensional structure and avoiding local excessive polymerization to form macromolecules with a molecular weight exceeding expectations.

[0050] According to an embodiment of the present invention, the dewatering agent may include but is not limited to silane 171; the catalyst may include but is not limited to at least one of chelated tin, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, zinc neodecanoate, butyltin dilaurate and stannous octoate; the dispersant may include but is not limited to at least one of f108 Hangzhou Lin'an auxiliary agent and Deqian Chemical 9250 dispersant, the defoaming agent may include but is not limited to BYK-066N defoamer produced by BYK Chemical, 5500 defoamer of Deqian Chemical and at least one of the silicone defoamers of Shanghai Tiger Chemical; the filler may include but is not limited to at least one of Jiangsu Qunxin's heavy calcium 101a or 201a, Jiangxi Kete's talc 1000, Qingzhou Yuxin's calcium hydrogen 601, Suzhou Lida's heavy calcium ld200 or ld600, Guangyuan heavy calcium cc1500 or cc1000, and talc dhs218.

[0051] The waterproof coating meets at least one of the following conditions:

[0052] The viscosity of the waterproof coating is 11500-16400 mPa.s;

[0053] The volatile organic compound content of the waterproof coating is not higher than 20g / L.

[0054] In some specific embodiments, the weight parts of each component in the waterproof coating can be shown in the following Table 1:

[0055] Table 1

[0056] Components content Silane modified polyurethane resin 13-35 parts by weight Hydrolytic coupling gel 1-3 parts by weight Silane modified UV resistant nanofiller 1-5 parts by weight Dispersants 0.1-0.3 parts by weight Defoaming agent 0.1-0.3 parts by weight filler 30-50 parts by weight Composite anti-sagging agent thixotropic paste 12-25 parts by weight Dewatering agent 1-3 parts by weight catalyst 0.05-0.1 parts by weight

[0057] In general, the waterproof coating proposed in the present disclosure may have at least one of the following advantages:

[0058] 1. The waterproof coating of the present invention is a single-component material, does not require machine stirring, reduces manual operation, and saves costs.

[0059] 2. The waterproof coating of the present invention has excellent weather resistance and can pass UV aging for 2500h. It has excellent weather resistance and anti-corrosion effects, excellent physical properties reaching 3MPa, and an elongation of more than 800%. It is particularly suitable for application in outdoor concrete surface waterproofing, decoration and protection.

[0060] 3. The waterproof coating of the present invention has excellent bonding performance to wet base surfaces and good water resistance, and the bonding strength reaches more than 80% after immersion in water.

[0061] 4. The waterproof coating of the present invention dries quickly at low temperatures, has high activity at low temperatures, forms a film quickly and solidifies quickly, and compared with conventional polyurethane, the drying speed is increased by more than 1 times.

[0062] 5. The waterproof coating of the present invention is a silane hydrolysis cross-linking curing, does not generate carbon dioxide gas during application, and the formed coating is bubble-free.

[0063] 6. The waterproof coating of the present invention is natural and environmentally friendly, does not contain organic solvents, has an extremely low content of volatile organic compounds (reaching below 20 g / L), and has a low viscosity, which is conducive to scraping construction and on-site application.

[0064] The viscosity of this one-component solvent-free silane-modified polyurethane is between 11500-16400mPa.s. It has smooth construction and can be constructed 1mm at a time without flowing. It does not contain solvents, is safe and environmentally friendly, has a fast curing speed, and dries quickly especially at low temperatures. It has a large wetting ability for the base layer, strong adhesion, and good bonding to various substrates. It can pass the 2500h UV aging test. The test results are shown in Table 2 below.

[0065] Table 2

[0066]

[0067] In another aspect of the present disclosure, the present disclosure proposes a method for preparing the aforementioned waterproof coating. Specifically, the method includes the following operations: forming a composite isocyanate, wherein the composite isocyanate is formed by reacting an isocyanate and a modifier containing silane at a temperature not higher than 20 degrees Celsius. Forming a silane-modified polyurethane resin, wherein the silane-modified polyurethane resin is formed by adding the composite isocyanate to a polyether polyol. Forming a silane-modified anti-UV nanofiller, wherein the modified anti-UV nanofiller is obtained by treating nanoparticles with the modifier. Subsequently, the silane-modified polyurethane resin, the silane-modified anti-UV nanofiller and the additive are mixed and degassed to obtain the waterproof coating.

[0068] Specifically, in the step of forming the composite isocyanate, isocyanate and a modifier may be added to cold water. The modifier may be a variety of the aforementioned silane coupling agents. For example, the first modifier may be added first and the temperature may be kept not higher than 20 degrees Celsius, and then the second modifier to the fourth modifier may be added dropwise in sequence, and each may be independently reacted for 0.5-1.5 hours and the temperature may be controlled not higher than 20 degrees Celsius. The first to fourth modifiers may be selected from any component of the aforementioned silane coupling agents. Specifically, the first modifier may be IPTS, the second modifier may be KH550, the third modifier may be KH560, and the fourth modifier may be KH570. The mass ratio of isocyanate, the first modifier, the second modifier, the third modifier and the fourth modifier is (7-10): (0.3-0.8): (0.05-0.2): (0.1-0.3): (0.2-0.5).

[0069] Specifically, the additives may include a composite anti-sagging agent thixotropic paste, and various additives contained in the aforementioned waterproof coating. Among them, the composite anti-sagging agent thixotropic paste can be obtained by physically mixing nano calcium, gas silica, wax powder and bentonite. For example, a plasticizer (including but not limited to chlorinated paraffin and diisononyl phthalate) can be added to a kneader, and then the temperature is raised to 100-120°C, and then an appropriate amount of nano calcium, gas silica, wax powder and bentonite are added, and the mixture is dehydrated and kneaded under vacuum-0.1MPa for 2-4h until the moisture content is below 0.1%, and the mixture is discharged into a pressure cylinder to obtain a composite anti-sagging agent thixotropic paste. The mass ratio of plasticizer, nano calcium, gas silica, wax powder and bentonite can be (100-150): (180-220): (2-5): (0.5-2): (0.5-2), wherein the mass ratio of chlorinated paraffin and diisononyl phthalate in the plasticizer can be (90-110): (20-40).

[0070] In a specific example of the present disclosure, the method may include the following steps:

[0071] 1. Formation of complex isocyanate:

[0072] Add appropriate amount of isocyanate (TDI) and first modifier (IPTS) to the reactor into which cooling water is introduced, and keep the temperature below 20°C, then slowly drop an appropriate amount of second modifier (WD50), drip it for 20-40 minutes, stir and control the temperature below 20°C to react for about 1 hour, then drop an appropriate amount of third modifier (KH560), stir and control the temperature below 20°C to react for about 1 hour, finally drop the fourth modifier (KH570), stir and control the temperature below 20°C to react for 1 hour, and finally discharge the terminal isocyanate containing silane group and epoxy group, vinyl group, and urea group. Among them, the mass ratio of TDI: IPTS: KH550: KH560: KH570 can be 9: 0.5: 0.1: 0.2: 0.3. The above reaction conditions are conducive to controlling the reaction rate within a more desired range, and thus obtaining a coating with good viscosity and molecular weight distribution.

[0073] 2. Hydrolysis coupling agent gel:

[0074] Add appropriate amount of silane modifier, such as KH550, KH560, KH570 coupling agent into the reactor, control the temperature at 60℃, then drop appropriate amount of distilled water, stir and control the temperature below 60℃ to react for about 1h to obtain the hydrolyzed coupling agent gel after partial hydrolysis of silane. The mass ratio of KH550: KH560: KH570: water is 1:2:3:0.1.

[0075] 3. Silane modified polyurethane resin:

[0076] Add an appropriate amount of polyether polyol to the reactor, heat it to 110°C for dehydration for more than 2 hours, test its moisture content to be less than 0.05%, then cool it to 80°C, add the composite isocyanate obtained in step 1 to the reactor, add it within 20 minutes, then stir and keep warm for 2 hours, test the isocyanate group content to be 0, indicating that the reaction is complete, then add the hydrolysis coupling agent gel in step 2 and stir for 0.5 hours, stop stirring and discharge. The mass ratio of polyether polyol: composite isocyanate: hydrolysis coupling agent gel can be 20:5:0.2.

[0077] 4. Silane modified UV-resistant nanofiller:

[0078] Add light-controlled nanomaterials to a vertical nitrogen-fixing powder dryer with bag dust collection and other devices, heat and stir while spraying a mixed solution formed by KH550, KH560, KH570 coupling agents and other components, the temperature does not exceed 80°C, stir, dry, modify and disperse for about 1 hour, turn on the nitrogen-fixing equipment, heat to 130°C for deep processing and drying for 3 hours, and test the moisture content below 0.05% before discharging to the cooling bin for standby. The light-controlled nanomaterial is obtained by mixing titanium oxide, tungsten oxide, cerium oxide and vanadium oxide in a ratio of 1:2:1:1, and the mass ratio of light-controlled nanomaterials: KH550: KH560: KH570 can be 10:0.01:0.02:0.03.

[0079] Silane-modified UV-resistant nanofillers can provide better integration of inorganic / organic material components in coatings.

[0080] 5. Composite anti-sagging agent thixotropic paste:

[0081] Add an appropriate amount of plasticizer (for example, chlorinated paraffin and diisononyl phthalate) to the kneader, then heat it to 110°C, add an appropriate amount of nano calcium, gas silica, wax powder and bentonite, dehydrate and knead for 2-4 hours under vacuum -0.1MPa until the moisture content is below 0.1%, and discharge it into a pressure cylinder. The thixotropic agent obtained after physical mixing is more suitable for the silane-modified polyurethane system of the present invention, which can assist in forming a good three-dimensional network structure, thereby improving the weather resistance and mechanical properties of the coating. The mass ratio of chlorinated paraffin: diisononyl phthalate: nano calcium: gas silica: wax powder: bentonite can be 100:30:200:2:1:1.

[0082] 6. Coating screw preparation

[0083] The silane-modified polyurethane resin in step 3, the silane-modified anti-UV nanofiller in step 4, the filler dried in advance to a moisture content of less than 0.05%, the composite anti-sagging agent thixotropic paste in step 5, and a mixture of auxiliary agents such as a dewatering agent, a catalyst, a dispersant, and a defoaming agent are accurately measured and put into a twin-screw machine, and a single-component silane-modified polyurethane waterproof coating is obtained by degassing, grinding, dispersing and extruding.

[0084] In general, the waterproof coating and preparation method proposed in the present invention mainly polymerize polysilane in a coordinated step-by-step manner with polyurethane, so that the obtained coating has excellent long-lasting adhesion to various base layers and has large cohesive energy, excellent tensile properties of the material, greatly improved water resistance, and fast drying at low temperature. In addition, the viscosity of the waterproof coating of the present invention is between 11500-16400mPa.s, the construction is smooth, 1mm can be constructed at a time without flowing, it does not contain solvents, is safe and environmentally friendly, has a fast curing speed, and dries quickly at low temperatures, has a large wetting ability for the base layer, strong adhesion, and has good adhesion to various substrates, and can pass a 2500h UV aging test.

[0085] In another aspect of the present disclosure, the present disclosure provides a coating, which is formed by using the aforementioned waterproof coating.

[0086] Example

[0087] The methods used in the following examples are conventional methods unless otherwise specified, and the reagents used are commercially available reagents unless otherwise specified. For example, the reagents used in each step can be as follows:

[0088] Nanoparticles: one or more of titanium dioxide, cerium oxide, zinc oxide, tungsten oxide, silicon oxide, vanadium oxide and other nanoscale materials, preferably with a particle size of 20-100 nm, purchased from the Institute of Organic Chemistry of the Yangtze River Delta Innovation Center.

[0089] Dispersant: Choose one or more of f108 Hangzhou Lin'an additive and Deqian Chemical 9250 dispersant.

[0090] Coupling agent: one or more of the silane coupling agents WD50, KH550, KH560, KH570, and IPST produced by Hubei Wuda Silicone Company.

[0091] Dewatering agent: Silane 171.

[0092] Catalyst: one or more of chelated tin, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, zinc neodecanoate, butyltin dilaurate and stannous octoate.

[0093] Defoaming agent: One or more of BYK-066N defoaming agent produced by BYK Chemical, 5500 defoaming agent produced by Deqian Chemical, and silicone defoaming agent produced by Shanghai Tiger Chemical.

[0094] Filler: one or more of the following: heavy calcium 101a or 201a from Jiangsu Qunxin, talc 1000 from Jiangxi Kete, calcium hydrogen 601 from Qingzhou Yuxin, heavy calcium ld200 or ld600 from Suzhou Lida, heavy calcium cc1500 or cc1000 from Guangyuan, and talc dhs218.

[0095] Isocyanate: any one or more of Wanhua Chemical’s TDI, MDI, HDI and HMDI.

[0096] Polyether polyol: any one or more of 2000d polyether polyol, 1000d polyether polyol, 3050d polyether polyol and 330Nd polyether polyol produced by Dongda Chemical.

[0097] Anti-sagging agent: Arkema LS polyethylene wax (wax powder), Wacker H18 hydrophobic silica, Changan Renheng's organic bentonite, Zhejiang Jinxiong CC601 nano calcium.

[0098] Example 1

[0099] This example provides a silane-modified waterproof coating, the raw materials of which include: 25 parts of the above-mentioned silane-modified polyurethane resin, 1 part of hydrolysis coupling agent gel, 3 parts of silane-modified anti-UV nano filler, 0.1 part of dispersant (Deqian Chemical 9250 dispersant), 0.2 part of defoamer (BYK-066N defoamer), 49.65 parts of filler (heavy calcium and talcum powder each account for 50%), 20 parts of composite anti-sagging agent thixotropic paste, 1 part of dewatering agent (Silane 171), and 0.05 part of catalyst (chelated tin).

[0100] The preparation method of the composite isocyanate, the hydrolysis coupling agent gel, the silane-modified polyurethane resin, the silane-modified anti-UV nanofiller and the composite anti-sagging agent thixotropic paste in the raw materials is as follows:

[0101] 1. Preparation method of composite isocyanate: add appropriate amount of isocyanate (TDI) and first modifier (IPTS) to the reactor into which cooling water is introduced, and keep the temperature below 20°C, then slowly dropwise add appropriate amount of second modifier (WD50), drip completely for 20-40min, stir and control the temperature below 20°C to react for about 1h, then dropwise add appropriate amount of third modifier (KH560), stir and control the temperature below 20°C to react for about 1h, finally dropwise add fourth modifier (KH570), stir and control the temperature below 20°C to react for 1h, and finally discharge the terminal isocyanate containing silane group, epoxy group, vinyl group and urea group. Among them, the mass ratio of TDI: IPTS: KH550: KH560: KH570 is 9: 0.5: 0.1: 0.2: 0.3.

[0102] 2. Preparation method of hydrolyzed coupling agent gel: add appropriate amount of silane modifiers KH550, KH560, KH570 into the reactor, control the temperature at 60°C, then drop appropriate amount of distilled water, stir and control the temperature below 60°C to react for about 1 hour. The mass ratio of KH550: KH560: KH570: water is 1:2:3:0.1.

[0103] 3. Preparation method of silane-modified polyurethane resin: add an appropriate amount of polyether polyol to the reactor, heat it to 110°C for dehydration for more than 2 hours, test its moisture content to be less than 0.05%, then cool it to 80°C, add the above-obtained composite isocyanate to the reactor, add it within 20 minutes, then stir and keep warm for 2 hours, test the isocyanate group content to be 0, indicating that the reaction is complete, then add the above-obtained hydrolysis coupling agent gel and stir for 0.5 hours, stop stirring and discharge. The mass ratio of polyether polyol: composite isocyanate: hydrolysis coupling agent gel is 20:5:0.2.

[0104] 4. Preparation method of silane-modified anti-UV nanofiller: Add light-controlled nanomaterials to a vertical nitrogen-fixing powder dryer with bag dust collection and other devices, heat and stir while spraying a mixed solution formed by KH550, KH560, KH570 coupling agents and other components, the temperature does not exceed 80°C, stir and dry the modified dispersion for about 1 hour, turn on the nitrogen-fixing equipment, heat to 130°C for deep processing and drying for 3 hours, and test the moisture content below 0.05% before discharging to the cooling bin for standby. The light-controlled nanomaterial is obtained by mixing titanium oxide, tungsten oxide, cerium oxide, and vanadium oxide in a ratio of 1:2:1:1, and the mass ratio of light-controlled nanomaterials: KH550: KH560: KH570 is 10:0.01:0.02:0.03.

[0105] 5. Preparation method of composite anti-sagging agent thixotropic paste: add appropriate amount of plasticizer (chlorinated paraffin and diisononyl phthalate) into the kneading machine, then heat up to 110℃, add appropriate amount of nano calcium, gas silicon, wax powder and bentonite, dehydrate and knead for 2-4 hours under vacuum -0.1MPa until the moisture content is below 0.1%, and discharge into the pressing cylinder. The mass ratio of chlorinated paraffin: diisononyl phthalate: nano calcium: gas silicon: wax powder: bentonite is 100:30:200:2:1:1.

[0106] The preparation method of the silane-modified waterproof coating comprises the following steps:

[0107] The above-mentioned silane-modified polyurethane resin, silane-modified anti-UV nanofiller, filler dried in advance to reduce the moisture content to less than 0.05%, composite anti-sagging agent thixotropic paste, as well as dewatering agent, catalyst, dispersant, defoaming agent and catalyst are accurately measured and put into a twin-screw machine respectively, and the single-component silane-modified polyurethane waterproof coating is obtained by degassing, grinding, dispersing and extruding.

[0108] Example 2

[0109] This example provides a silane-modified waterproof coating, the raw materials of which include: 20 parts of the above-mentioned silane-modified polyurethane resin, 1 part of hydrolysis coupling agent gel, 3 parts of silane-modified anti-UV nano filler, 0.1 part of dispersant (Deqian Chemical 9250 dispersant), 0.2 part of defoamer (BYK-066N defoamer), 49.65 parts of filler (50% each of heavy calcium and talcum powder), 25 parts of composite anti-sagging agent thixotropic paste, 1 part of dewatering agent (Silane 171), and 0.05 part of catalyst (chelated tin).

[0110] The preparation method of the composite isocyanate, hydrolysis coupling agent gel, silane-modified polyurethane resin, silane-modified anti-UV nanofiller and composite anti-sagging agent thixotropic paste in the raw materials is the same as that in Example 1.

[0111] The preparation method of the silane-modified waterproof coating comprises the following steps:

[0112] Silane-modified polyurethane resin, silane-modified anti-UV nanofiller, filler dried in advance to reduce moisture content to less than 0.05%, composite anti-sagging agent thixotropic paste, dewatering agent, catalyst, dispersant, defoaming agent and catalyst are accurately weighed and respectively put into a twin-screw machine, and a single-component silane-modified polyurethane waterproof coating is obtained by degassing, grinding, dispersing and extruding.

[0113] Example 3

[0114] This example provides a silane-modified waterproof coating, the raw materials of which include: 25 parts of the above-mentioned silane-modified polyurethane resin, 1 part of hydrolysis coupling agent gel, 5 parts of silane-modified anti-UV nano filler, 0.1 part of dispersant (Deqian Chemical 9250 dispersant), 0.3 part of defoamer (BYK-066N defoamer), 49.65 parts of filler (50% each of heavy calcium and talcum powder), 18.9 parts of composite anti-sagging agent thixotropic paste, 1 part of dewatering agent (Silane 171), and 0.05 part of catalyst (chelated tin).

[0115] The preparation method of the composite isocyanate, hydrolysis coupling agent gel, silane-modified polyurethane resin, silane-modified anti-UV nanofiller and composite anti-sagging agent thixotropic paste in the raw materials is the same as that in Example 1.

[0116] The preparation method of the silane-modified waterproof coating comprises the following steps:

[0117] Silane-modified polyurethane resin, silane-modified anti-UV nanofiller, filler dried in advance to reduce moisture content to less than 0.05%, composite anti-sagging agent thixotropic paste, dewatering agent, catalyst, dispersant, defoaming agent and catalyst are accurately weighed and respectively put into a twin-screw machine, and a single-component silane-modified polyurethane waterproof coating is obtained by degassing, grinding, dispersing and extruding.

[0118] Comparative Example 1

[0119] The method is basically the same as Example 1, except that the raw materials do not include the silane-modified anti-UV nanofiller, and all other materials are increased and supplemented in the same proportion.

[0120] Comparative Example 2

[0121] The method is basically the same as Example 1, except that the raw materials do not include the hydrolyzable coupling agent gel, and all other materials are increased and supplemented in the same proportion. In addition, the preparation method of the silane-modified polyurethane resin does not include the step of adding the hydrolyzable coupling agent gel for stirring.

[0122] Comparative Example 3

[0123] The method is basically the same as Example 1, except that no silane is added to the silane-modified resin, and all other materials are increased and supplemented in the same proportion.

[0124] Performance Testing

[0125] The waterproof coatings prepared in the above-mentioned Examples 1-3 and Comparative Examples 1-3 were subjected to the following performance tests, and the specific results are shown in Table 3.

[0126] Table 3

[0127]

[0128]

[0129] It can be seen from the above table that the coatings of the embodiments of the present disclosure all have good performance, high weather resistance, high bonding strength to wet base surfaces, high adhesive strength, and good anti-sagging properties.

[0130] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0131] The disclosure above provides many different embodiments or examples to implement different structures of the present disclosure. In order to simplify the present disclosure, the components and settings of specific examples are described above. Of course, they are only examples, and the purpose is not to limit the present disclosure. In addition, the present disclosure can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed.

[0132] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A waterproof coating, characterized in that: The raw materials for forming the waterproof coating include: Silane modified polyurethane resin; Silane modified UV resistant nanofillers; and additive, The silane-modified polyurethane resin is obtained by reacting a silane-modified composite isocyanate and a polyether polyol. The silane-modified polyurethane resin and the silane-modified anti-UV nanofiller have a silane group, an epoxy group, a vinyl group, and optionally a urea group.

2. The waterproof coating according to claim 1, characterized in that: The silane-modified polyurethane resin and the silane-modified anti-UV nanofiller are obtained by modification with a modifier, wherein the modifier includes a silane coupling agent. The silane coupling agent includes any one or more of WD50, KH550, KH560, KH570, and IPST.

3. The waterproof coating according to claim 2, characterized in that: The silane coupling agent includes various coupling agents.

4. The waterproof coating according to claim 3, characterized in that: The mass ratio of isocyanate to the silane coupling agent in the raw materials for forming the composite isocyanate is (7-10): (0.8-2).

5. The waterproof coating according to claim 1, characterized in that: The raw materials for forming the waterproof coating further include hydrolysis coupling gel, and the hydrolysis coupling gel is formed by hydrolysis reaction of multiple silane coupling agents.

6. The waterproof coating according to claim 1, characterized in that: The silane-modified anti-UV nanofiller is formed by nanoparticles and a modifier. The nanoparticles include at least one of titanium dioxide, cerium oxide, zinc oxide, tungsten oxide, silicon oxide and vanadium oxide, The modifier includes various silane coupling agents.

7. The waterproof coating according to claim 1, characterized in that: The additives include a composite anti-sagging agent thixotropic paste, and optionally at least one of a dewatering agent, a catalyst, a dispersant, a defoaming agent and a filler. The composite anti-sagging agent thixotropic paste comprises nano calcium, gas silicon, wax powder and bentonite.

8. The waterproof coating according to claim 1, characterized in that: In the raw materials for forming the silane-modified polyurethane resin, the mass ratio of the complex isocyanate to the polyether polyol is (3-8): (15-30).

9. The waterproof coating according to claim 1, characterized in that: Satisfy at least one of the following conditions: The viscosity of the waterproof coating is 11500-16400 mPa.s; The volatile organic compound content of the waterproof coating is not higher than 20g / L.

10. A method for preparing the waterproof coating according to any one of claims 1 to 9, characterized in that: include: Forming a composite isocyanate, wherein the composite isocyanate is formed by reacting an isocyanate and a modifier containing a silane at a temperature not higher than 20 degrees Celsius; forming a silane-modified polyurethane resin, wherein the silane-modified polyurethane resin is formed by adding the complex isocyanate to a polyether polyol; forming a silane-modified anti-UV nanofiller, wherein the modified anti-UV nanofiller is obtained by treating nanoparticles with the modifier, The silane-modified polyurethane resin, the silane-modified anti-UV nanofiller and the additive are mixed and subjected to a degassing treatment to obtain the waterproof coating.

11. The method according to claim 10, characterized in that The method satisfies at least one of the following conditions: When forming the composite isocyanate, the isocyanate and the first modifier are added to cold water and the temperature is maintained at no more than 20 degrees Celsius, and then the second modifier to the fourth modifier are sequentially added dropwise, and each is independently reacted for 0.5-1.5 hours and the temperature is controlled to be no more than 20 degrees Celsius, and the mass ratio of the isocyanate, the first modifier, the second modifier, the third modifier and the fourth modifier is (8-10): (0.3-0.8): (0.05-0.2): (0.1-0.3): (0.2-0.5); When forming the silane-modified polyurethane resin, the polyether polyol is subjected to a temperature-raising dehydration treatment to make its moisture content no higher than 0.05%, and then the composite isocyanate is added to the polyether polyol to react for 2-4 hours until the isocyanate group content is 0; The additive comprises a composite anti-sagging agent thixotropic paste, and the composite anti-sagging agent thixotropic paste is obtained by physically mixing nano calcium, gas silicon, wax powder and bentonite.

12. The method according to claim 10, characterized in that Further comprising the operation of forming a hydrolyzed coupling agent gel, The operation of forming the hydrolyzable coupling agent gel comprises mixing and stirring a plurality of silane coupling agents and water in a closed container to perform a hydrolysis reaction.

13. The method according to claim 11, characterized in that When forming the silane-modified polyurethane resin, it further comprises: After the composite isocyanate is added to the polyether polyol and reacted until the isocyanate group content is 0, the hydrolysis coupling agent gel is added and reacted for 20-120 minutes.

14. A coating, characterized in that: The coating is formed using the waterproof coating according to any one of claims 1 to 9.

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