A fire-retardant coating with high fire-retardant stability, a preparation method thereof and application thereof

Abstract

The present application relates to the field of IPC classification C09D, and more particularly to a high flame-retardant stability flame-retardant coating and a preparation method and application thereof. The high flame-retardant stability flame-retardant coating comprises the following components in parts by weight: polyhydric alcohol 80-120 parts, functional additives 30-80 parts, acid ester 40-80 parts, and solvent 100-200 parts. The high flame-retardant stability flame-retardant coating provided by the present application has good flame-retardant performance, can effectively prevent high-temperature conduction, further effectively protects the base material, has good storage stability during use, and has a broad development prospect.

Description

Technical Field

[0001] This invention relates to the field of C09D in the IPC classification, and more particularly to a flame-retardant coating with high flame-retardant stability, its preparation method, and its application. Background Technology

[0002] With social progress and economic development, more and more coatings are being used in people's production and daily lives. Furthermore, recent fire incidents have served as a stark reminder of the importance of fire prevention, leading to flame-retardant coatings receiving more attention than similar products. However, existing flame-retardant coatings typically incorporate metal oxides, metal hydroxides, halogenated flame retardants, and nitrogen and phosphorus compounds as flame retardants. While these flame retardants can provide good flame-retardant effects, they often negatively impact high-temperature barrier properties, water resistance, stability, service life, and shelf life.

[0003] The prior art (CN201711246622.2) provides a flame-retardant waterborne polyurethane coating, whose raw materials mainly include polyurethane resin, modified quartz sand, modified exfoliated fibers, and linseed oil. It mainly relies on the flame-retardant effects of flame retardants and silica to achieve flame retardancy in the coating. Although it can form a strong fiber network to increase the coating strength, its high-temperature insulation and protection performance for the substrate are poor. It is prone to flame retardancy but thermal melting and cracking of the protective substrate. Furthermore, it has poor compatibility and lacks broad applicability.

[0004] Therefore, there is an urgent need for a flame-retardant coating that not only has excellent flame-retardant properties, but also effectively blocks high-temperature transmission, effectively protects the substrate, and has excellent long-term storage and service life. Summary of the Invention

[0005] To address the aforementioned problems, the first aspect of this invention provides a flame-retardant coating with high flame-retardant stability, wherein the raw materials, by weight, include the following components: 80-120 parts of polyols, 30-80 parts of functional additives, 40-80 parts of esters, and 100-200 parts of solvents.

[0006] As a preferred embodiment, the polyol is at least one of polyester polyol, bio-based polyol, and polyether polyol.

[0007] As a preferred embodiment, the polyol is a polyether polyol.

[0008] As a preferred embodiment, the functional additive is at least three of the following: catalyst, coupling agent, chain extender, neutralizer, flame retardant, ultraviolet absorber, hydrolytic agent, anti-drip agent, antioxidant, and filler.

[0009] As a preferred embodiment, the functional additive is a catalyst, coupling agent, chain extender, neutralizer, or flame retardant.

[0010] As a preferred embodiment, the catalyst is dibutyltin dilaurate.

[0011] As a preferred embodiment, the coupling agent is any one of KH-550, KH-560, and KH-570.

[0012] As a preferred embodiment, the chain extender is at least one of dimethylolpropionic acid and diaminobenzoic acid.

[0013] As a preferred embodiment, the chain extender is dimethylolpropionic acid.

[0014] As a preferred embodiment, the neutralizing agent is at least one of acetic acid, triethanolamine, and ammonia.

[0015] As a preferred option, the filler is barium sulfate.

[0016] As a preferred embodiment, the barium sulfate is pretreated modified barium sulfate. The modification steps include the following steps: (1) mixing barium sulfate with ammonia water and stirring, then adding it to an ethanol solution and stirring until homogeneous; (2) preparing tetraethyl orthosilicate and ethanol into a dropwise solution and adding it dropwise to the mixture in step (1) while stirring, with a reaction time of 3 to 5 hours; (3) filtering and drying after the reaction is complete to obtain the product.

[0017] As a preferred embodiment, the solvent is at least one of organic ketones, organic alcohols, and organic amides.

[0018] As a preferred option, the solvent is acetone.

[0019] As a preferred embodiment, the flame retardant is at least one of nitrogen-phosphorus flame retardants, metal oxide flame retardants, and halogen flame retardants.

[0020] As a preferred embodiment, the mass ratio of the nitrogen-phosphorus composite flame retardant to the polyol is 2-3:10-11.

[0021] As a preferred method, the preparation method of nitrogen-phosphorus composite flame retardant includes the following steps (by mass): (1) Add 10-15 parts of polyphosphoric acid to the reaction vessel, then add 6-8 parts of melamine and 80-100 parts of deionized water, and stir evenly; (2) Add 20-24 parts of hydroquinone and 8-10 parts of ethylene glycol, heat to 50-60℃ and stir to accelerate the reaction; (3) After the reaction is completed, cool to room temperature and add ammonia water to adjust the pH to 7, filter and wash; (4) Pulverize the obtained solid material together with 5-8 parts of melamine pyrophosphate and 10-15 parts of pentaerythritol evenly to obtain the final product.

[0022] As a preferred embodiment, the ester is any one of toluene diisocyanate, isophorone diisocyanate, and diphenylmethane diisocyanate.

[0023] As a preferred embodiment, the mass ratio of the ester to the polyol is 5-7:10-11.

[0024] As a preferred embodiment, the mass ratio of the ester to the polyol is 6:10.5.

[0025] In this application, by adding specifically modified barium sulfate filler, not only can the mechanical properties and radiation protection effect of the flame-retardant coating be effectively improved, but its addition can also effectively improve the overall long-term storage stability and service life of the coating system. The applicant hypothesizes that the amorphous oxide film layer on the surface of the modified barium sulfate has good low surface energy, allowing the barium sulfate to have good dispersibility in the resin system while also enabling direct contact between the barium sulfate and the nitrogen-phosphorus composite flame retardant. This avoids the reaction between the multiple acid sources in the nitrogen-phosphorus composite material and the barium sulfate, thereby stabilizing the overall esterification reaction process of the nitrogen-phosphorus composite material and reducing coating deactivation.

[0026] The second aspect of the present invention provides a method for preparing the above-mentioned high flame retardant stability flame retardant coating, characterized in that the steps include the following steps: (1) weighing all the required raw materials and adding them to a reaction vessel, heating to 40-60°C and stirring to mix evenly to obtain a mixture; (2) maintaining the reaction for 6-10 hours, finally adding deionized water and stirring to emulsify, and removing the solvent by vacuuming to obtain the final product.

[0027] A third aspect of the present invention provides an application of the above-mentioned flame-retardant coating with high flame-retardant stability, including the application of the flame-retardant coating with high flame-retardant stability in solar photovoltaic modules.

[0028] Beneficial effects:

[0029] 1. The flame-retardant coating provided in this application has excellent flame-retardant properties and high-temperature barrier properties. In particular, it can prevent the protected substrate from being affected by high temperature while being flame-retardant. When the flame-retardant coating is applied to the surface of a soft plastic substrate, the foamed layer formed blocks the transmission of high temperature through air isolation and carbon isolation, thereby preventing the soft plastic material from melting and cooling cracking due to reaching its own melting temperature.

[0030] 2. The flame-retardant paint provided in this application can form a foamed carbon layer on the paint surface through the esterification of carbon, acid and gas sources in a specific nitrogen-phosphorus composite material under high temperature and combustion environment. While isolating combustion from air, it also provides high-temperature barrier through poor conductor.

[0031] 3. The flame-retardant paint provided in this application effectively improves the coating mechanical properties and radiation protection effect of the flame-retardant coating by modifying the filler barium sulfate. Its addition can also effectively improve the overall long-term storage stability and service life of the coating system. Detailed Implementation

[0032] Example 1

[0033] Example 1 provides a flame-retardant coating with high flame-retardant stability, comprising, by weight, 105 parts of polyol, 70 parts of functional additives, 70 parts of ester, and 120 parts of solvent.

[0034] Among them, polypolyols are polyether polyols.

[0035] The functional additives are catalysts, coupling agents, chain extenders, neutralizers, and flame retardants, in a mass ratio of 3:7:10:5:25:20.

[0036] The coupling agent is KH-570; the catalyst is dibutyltin dilaurate; the chain extender is dimethylolpropionic acid; the neutralizer is acetic acid; the flame retardant is a nitrogen-phosphorus composite flame retardant; and the filler is modified barium sulfate.

[0037] The ester is toluene diisocyanate.

[0038] The solvent is acetone.

[0039] The preparation method of nitrogen-phosphorus composite flame retardant includes the following steps: (by mass) (1) Add 13 parts of polyphosphoric acid to the reaction vessel, then add 6 parts of melamine and 100 parts of deionized water, and stir evenly; (2) Add 22 parts of hydroquinone and 10 parts of ethylene glycol, heat to 55℃ and stir to accelerate the reaction; (3) After the reaction is completed, cool to room temperature and add ammonia water to adjust the pH to 7, filter and wash; (4) Pulverize the obtained solid material together with 6 parts of melamine pyrophosphate and 12 parts of pentaerythritol evenly to obtain the final product.

[0040] The preparation steps of modified barium sulfate include the following steps: (by mass) (1) Mix 2 parts of barium sulfate with 10 parts of ammonia water and stir, then add to 100 parts of ethanol solution and stir until homogeneous; (2) Prepare a dropping solution by mixing 15 parts of tetraethyl orthosilicate with 60 parts of ethanol, and add it dropwise to the mixture in step (1) while stirring, and the reaction time is 3.5 hours; (3) After the reaction is completed, filter and dry to obtain the product.

[0041] The second aspect of this embodiment provides a method for preparing the above-mentioned coating, the steps of which include the following steps: (1) weighing polyols, functional additives and solvents, adding them to a reaction vessel, heating to 55°C and stirring to mix evenly to obtain a mixture; (2) adding an acid ester to the mixture, heating to 80°C and stirring under nitrogen protection for 8 hours, cooling to room temperature, adding deionized water and stirring to emulsify, removing the solvent by vacuum to obtain the coating.

[0042] In this embodiment, the polyether polyol is an industrial-grade polyether polyol product with a molecular weight rating of 5000 sold by Jinan Hongwang Chemical Co., Ltd.

[0043] Example 2

[0044] The specific implementation method of this embodiment is the same as that of Embodiment 1, except that the amount of polyol is 50 parts.

[0045] Comparative Example 1

[0046] The specific implementation method of this comparative example is the same as that of Example 1, except that the modified barium sulfate is 10 parts.

[0047] Comparative Example 2

[0048] The specific implementation method of this comparative example is the same as that of Example 1, except that ordinary barium sulfate is added to the system instead of modified barium sulfate.

[0049] Performance Evaluation

[0050] Storage stability: Samples of the coatings prepared in all examples and comparative examples were taken, placed in a constant temperature oven at 40°C, and stirred at 100 rpm / min. After 7 days, the samples were taken out and observed for the precipitation of impurity particles and the outflow of milky white flocculent material. If any of these were found, the samples were considered unqualified. 100 samples were tested for each example and comparative example. 0-10 unqualified samples were classified as A, 10-20 as B, and more than 20 as C.

[0051] Flame retardancy test: After the paints prepared in the examples and comparative examples were stirred in an open container and stored for 3 months, they were brushed onto the surface of the back panel. Then, a blowtorch flame was brought into contact with the surface of the paint layer (1 mm thick) at a vertical angle, with the outer blue flame (approximately 600°C) contacting the test sample. After the flame came into contact with the flame retardant paint layer, the temperature change of the back panel over time was recorded. The temperature of the back panel was recorded after 10 minutes, and any cracking or melting phenomena were observed. 100 samples were tested for each example and comparative example. 0-5 unqualified samples were classified as A, 5-15 as B, and more than 15 as C.

[0052] Table 1

[0053] Example Storage stability Flame retardancy Example 1 A A Example 2 A A Comparative Example 1 B B Comparative Example 2 B B

[0054] As can be seen from Examples 1-2, Comparative Examples 1-2, and Table 1, the flame-retardant coating with high flame-retardant stability provided by the present invention not only has good flame-retardant properties but also effectively prevents high-temperature conduction, further effectively protecting the substrate material. Furthermore, it exhibits good storage stability during use and has broad development prospects. Example 1, in particular, achieved the best performance index under optimal raw material ratios and preparation processes.

Claims

1. A flame-retardant coating with high flame-retardant stability, characterized in that, By weight, the raw materials include the following components: 80-120 parts of polyols, 30-80 parts of functional additives, 40-80 parts of esters, and 100-200 parts of solvents; The polyols mentioned are polyether polyols; The functional additives are catalysts, coupling agents, chain extenders, neutralizers, flame retardants, and fillers, and the mass ratio of the catalysts, coupling agents, chain extenders, neutralizers, flame retardants, and fillers is 3:7:10:5:25:

20. The flame retardant is a nitrogen-phosphorus composite flame retardant; the mass ratio of the nitrogen-phosphorus composite flame retardant to the polyol is 2~3:10~11; The filler is pretreated modified barium sulfate. The modification steps include the following steps: (1) mix barium sulfate with ammonia water and stir, then add it to an ethanol solution and stir until it is evenly mixed; (2) prepare tetraethyl orthosilicate and ethanol into a drop solution and add it dropwise to the mixture in step (1) while stirring. The dropwise reaction time is 3 to 5 hours; (3) filter and dry after the reaction is completed to obtain the product. The ester is any one of toluene diisocyanate, isophorone diisocyanate, and diphenylmethane diisocyanate; The mass ratio of the ester to the polyol is 5~7:10~11; The solvent is acetone; The preparation method of the flame-retardant coating includes the following steps: (1) Weigh out the polyols, functional additives and solvents, add them to the reaction vessel, heat to 55°C and stir to mix evenly to obtain a mixture; (2) Add ester to the mixture, heat to 80°C and stir under nitrogen protection for 8 hours. Cool to room temperature, add deionized water and stir to emulsify. Remove solvent by vacuum to obtain the final product.

2. The application of a flame-retardant coating with high flame-retardant stability according to claim 1 in solar photovoltaic modules.