A preparation process of waterproof spray material

Abstract

The invention discloses a preparation process of a waterproof spray material, belonging to the technical field of waterproof coatings. The raw materials include the following parts by weight: 20-40 parts of MDI, 0.05-0.1 parts of dibutyltin oxide, 30-50 parts of polypropylene glycol, 10-20 parts of PET, 5-15 parts of modified diols, 150-200 parts of acetone, 4-8 parts of 1,4-butanediol, 0.1-0.3 parts of initiator, 8-16 parts of silane coupling agents, and 100-200 parts of deionized water. PET can enhance the mechanical properties of the material; polyurethane can be modified by using a silane coupling agent to improve the waterproofness and heat resistance of the material; modified diol can significantly enhance the flame retardancy and waterproofness of the material, and the performance is long-term and stable; therefore, the material prepared by the present invention has stable and efficient flame retardancy and waterproofness, and excellent heat resistance and mechanical properties, and has important application value in the technical field of waterproof coatings.

Description

Technical Field

[0001] The invention belongs to the technical field of waterproof coatings, and in particular, relates to a preparation process of a waterproof spray material. Background Art

[0002] Spray coating is a process method that uses spray equipment to evenly apply paint to the surface of an object. This technology is widely used in industries such as construction, automobiles, aerospace, and furniture manufacturing. Common coatings include oil-based paint, powder coating, and water-based paint. Oil-based paint: solvent-based paint that dries quickly and is suitable for a variety of surfaces. Powder coating: applied through electrostatic spraying, suitable for metal surfaces, and has no VOC emissions. And water-based paint: water-based paint, more environmentally friendly, with a lower VOC (volatile organic compound) content, in line with the development concept of ecological and environmental protection, has received more and more attention from experts and scholars in recent years.

[0003] Common polyurethane water-based paint is a polymer material developed by using water as a dispersant medium instead of organic solvents in traditional polyurethane. In addition to being environmentally friendly, it also has the advantages of good construction performance, high solid content, good fullness, high paint film hardness, high wear resistance and impact resistance. However, the waterproof performance of polyurethane water-based paint is poor, which makes it difficult to meet the growing production needs.

[0004] SPU waterproof coating is a polyurethane waterproof material. Specifically, it belongs to silane-modified polyurethane (SPU for short), which is a polyurethane material modified by silane. SPU waterproof coating is widely used in various water-using environments due to its high strength, good elasticity, waterproofness, and wear resistance. This material not only has stable performance, but also is easy to construct, and can be divided into different models to meet different waterproofing needs. However, polyurethane is an organic polymer, which is flammable and has poor flame retardant properties. Therefore, it is urgent to invent a flame retardant waterproof spray material to meet the higher demands in the field of waterproof coating technology. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a preparation process of a waterproof spray material.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A preparation process of a waterproof spray material comprises the following steps:

[0008] Under nitrogen protection, MDI (4,4'-diphenylmethane diisocyanate), dibutyltin oxide (catalyst), polypropylene glycol, polyethylene terephthalate (PET), modified diol and acetone were added to a three-necked flask equipped with a stirring reflux device, stirred and mixed evenly, and reacted at 40°C for 2h; 1,4-butanediol (BDO, chain extender) was added, and reacted at 50°C for 2h; initiator and silane coupling agent were added, the temperature was raised to 60°C and reacted for 4h, deionized water was added, high-speed shear emulsification was performed for 45min, and acetone was removed by reduced pressure rotary evaporation to obtain a waterproof spray material.

[0009] Furthermore, the raw materials are calculated in parts by weight as follows: 20-40 parts of MDI, 0.05-0.1 parts of dibutyltin oxide, 30-50 parts of polypropylene glycol, 10-20 parts of PET, 5-15 parts of modified diol, 150-200 parts of acetone, 4-8 parts of 1,4-butanediol, 0.1-0.3 parts of initiator, 8-16 parts of silane coupling agent, and 100-200 parts of deionized water.

[0010] Furthermore, the initiator is one of cyclohexanone peroxide and dibenzoyl peroxide.

[0011] Furthermore, the silane coupling agent is one of KH-550, KH-560 and KH-792.

[0012] PET has good mechanical properties, and the introduction of PET can enhance the mechanical properties of the coating; using silane coupling agent to modify polyurethane, the silane alkoxy group will hydrolyze to form high bond energy, low surface energy silicon oxygen bond, which can improve the waterproofness and heat resistance of the material.

[0013] Further, the modified diol is prepared by the following steps:

[0014] S1. At room temperature, tartaric acid, DAST (diethylaminosulfur trifluoride, fluorination reagent) and dichloromethane were added to a flask and stirred to mix evenly. The mixture was reacted for 55 min, filtered, the filter cake was taken, washed with anhydrous ethanol for 3 times, and dried to obtain intermediate 1. The ratio of tartaric acid, DAST and dichloromethane was 14.9 g:8.5 g:100 mL.

[0015] Under the action of the fluorination reagent, the hydroxyl group on the tartaric acid is converted into a difluorinated compound. The fluorination reagent is selective and the carboxyl group is not affected, thereby obtaining the intermediate 1. The specific reaction process is as follows:

[0016]

[0017] S2. In a three-necked flask equipped with a stirring device, tris(hydroxymethyl)aminomethane hydrochloride, triethylamine and DMF were mixed at room temperature, placed in an ice-water bath at 2°C, and stirred for 45 minutes, and then phosphorus oxychloride was slowly added dropwise, and the temperature was controlled not to exceed 18°C ​​during the addition. After the addition was completed, the temperature was raised to 90°C and the reaction was kept warm for 10 hours. After the reaction was completed, the solvent was removed by filtration under reduced pressure, and the filter cake was washed 2-3 times with anhydrous ethanol, vacuum dried, and ground to obtain intermediate 2; the ratio of tris(hydroxymethyl)aminomethane hydrochloride, triethylamine, DMF, and phosphorus oxychloride was 15.9g:14.4g:100mL:15.6g;

[0018] Tris(hydroxymethyl)aminomethane hydrochloride reacts with phosphorus oxychloride to obtain intermediate 2; the specific reaction process is as follows:

[0019]

[0020] S3. Add intermediate 1 and N,N-dimethylformamide (DMF) to a three-necked flask equipped with a stirring device, heat to 45°C and stir continuously until intermediate 1 is completely dissolved; introduce nitrogen, add intermediate 2 and dicyclohexylcarbodiimide (DCC, dehydrating agent), mix and stir evenly, heat to 50°C, and keep the temperature to react for 75 minutes. After the reaction is completed, filter, remove the solvent by vacuum distillation, and vacuum dry to obtain intermediate 3; the ratio of intermediate 1, N,N-dimethylformamide, intermediate 2, and dicyclohexylcarbodiimide is 16.7g:100mL:16.5g:20.6g;

[0021] The carboxyl group on intermediate 1 and the amino group on intermediate 2 undergo an amidation reaction. Under the action of a dehydrating agent, the reaction can be carried out under relatively mild conditions. By controlling the molar ratio of the two to be close to 1:1 and a slight excess of intermediate 1, only one carboxyl group on intermediate 1 participates in the reaction to obtain intermediate 3. The specific reaction process is as follows:

[0022]

[0023] S4. In a three-necked flask equipped with a stirring device, 1,3-diamino-2-propanol, intermediate 3 and N,N-dimethylformamide were mixed and stirred evenly, dicyclohexylcarbodiimide was added, and the device was placed in a water bath, and the reaction was kept at 55°C for 90 minutes. After the reaction was completed, it was filtered, most of the solvent was removed by rotary evaporation, and then purified by column chromatography (the eluent was a mixed solvent of ethyl acetate / benzene, and the volume ratio of the two was 4:1), and the eluent was removed by rotary evaporation to obtain intermediate 4; the ratio of 1,3-diamino-2-propanol, intermediate 3, N,N-dimethylformamide, and dicyclohexylcarbodiimide was 10.4g:30.1g:200mL:20.6g;

[0024] The carboxyl group on intermediate 3 reacts with the amino group of 1,3-diamino-2-propanol to undergo an amidation reaction. Under the action of a dehydrating agent, the reaction can be carried out under relatively mild conditions. By controlling the molar ratio of the two to be close to 1:1 and a slight excess of 1,3-diamino-2-propanol, only one amino group on 1,3-diamino-2-propanol participates in the reaction to obtain intermediate 4. The specific reaction process is shown below:

[0025]

[0026] S5. In a three-necked flask equipped with a stirring device, terephthalaldehyde, intermediate 4 and N,N-dimethylformamide were mixed, vigorously stirred, piperidine (condensing agent) was added, the reaction temperature was controlled to 70°C, the reaction was kept warm for 8 hours, the reaction was completed, the solvent was removed by reduced pressure distillation, the mixture was washed with anhydrous ethanol for 3-4 times, and vacuum dried to obtain a modified diol; the ratio of terephthalaldehyde, intermediate 4, N,N-dimethylformamide and piperidine was 13.4g:75.4g:150mL:30mL;

[0027] Under the action of the condensing agent, the aldehyde group on the terephthalaldehyde condenses with the amino group on the intermediate 4 to form an imine group (C=N Schiff base structure). By controlling the molar ratio of the two to be close to 1:2 and the intermediate 4 to be slightly excessive, a modified diol is obtained; the specific reaction process is as follows:

[0028]

[0029] The obtained modified diol has a benzene ring as the center and a functional group connected by a C=N bond. The two hydroxyl groups enable the modified diol to participate in the polymerization reaction during the polymerization with isocyanate, making it difficult for the modified diol to precipitate and fall off, thereby improving the long-term stability of the performance of the modified diol. In addition, the modified diol molecule also contains a CF bond, a caged phosphonate and a Schiff base structure. The CF bond has a high chemical bond and good stability, and can give the substrate significant waterproofness. It can also coat the CC main chain to reduce the surface of the substrate. surface energy, improving the stability of the matrix; not only that, the F element can also play a role in the joint modification of fluorine and silicon with silicone, significantly enhancing the waterproof performance of the matrix; in addition, the caged phosphonate structure is a green and environmentally friendly flame retardant with strong stability. When burned, it will promote the formation of a carbon layer, inhibit the release of smoke, and improve the flame retardant and smoke suppression properties of the matrix; in addition, the C=N double bond in the Schiff base structure can generate a carbon-nitrogen six-membered ring at high temperature. This type of six-membered ring structure enables the matrix to form a stable cross-linked network, which can play a synergistic role with the caged phosphonate and greatly enhance the flame retardant properties of the matrix.

[0030] Beneficial effects of the present invention:

[0031] 1. The material prepared by the present invention can enhance the mechanical properties of the material by introducing PET; the waterproofness and heat resistance of the material can be improved by modifying the polyurethane with a silane coupling agent;

[0032] 2. The functional groups contained in the prepared modified diol molecules can play a synergistic role, significantly enhancing the flame retardancy and waterproof properties of the material, and the performance is long-term and stable;

[0033] Therefore, the material prepared by the present invention has stable and efficient flame retardancy and waterproofness, and excellent heat resistance and mechanical properties, and has important application value in the field of waterproof coating technology. DETAILED DESCRIPTION

[0034] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Example 1

[0036] Preparation of modified diols:

[0037] S1. At room temperature, add 14.9 g tartaric acid, 8.5 g DAST and 100 mL dichloromethane into a flask, stir and mix evenly, react for 55 min, filter, take the filter cake, wash it with anhydrous ethanol for 3 times, and dry it to obtain intermediate 1;

[0038] S2. In a three-necked flask equipped with a stirring device, 15.9 g of tris(hydroxymethyl)aminomethane hydrochloride, 14.4 g of triethylamine and 100 mL of DMF were mixed at room temperature, placed in an ice-water bath at 2°C, and stirred for 45 min. Then, 15.6 g of phosphorus oxychloride was slowly added dropwise, and the temperature was controlled not to exceed 18°C ​​during the addition. After the addition was completed, the temperature was raised to 90°C and kept for reaction for 10 h. After the reaction was completed, the solvent was removed by filtration under reduced pressure, and the filter cake was washed twice with anhydrous ethanol, vacuum dried, and ground to obtain intermediate 2.

[0039] S3, add 16.7g of intermediate 1 and 100mL of N,N-dimethylformamide to a three-necked flask equipped with a stirring device, heat to 45°C and stir continuously until intermediate 1 is completely dissolved; introduce nitrogen, add 16.5g of intermediate 2 and 20.6g of dicyclohexylcarbodiimide, mix and stir evenly, heat to 50°C, keep warm and react for 75min, filter after the reaction, remove the solvent by distillation under reduced pressure, and dry in vacuo to obtain intermediate 3;

[0040] S4, in a three-necked flask equipped with a stirring device, 10.4g of 1,3-diamino-2-propanol, 30.1g of intermediate 3 and 200mL of N,N-dimethylformamide were mixed and stirred evenly, 20.6g of dicyclohexylcarbodiimide was added, the device was placed in a water bath, and the reaction was kept at 55°C for 90min. After the reaction was completed, it was filtered, most of the solvent was removed by rotary evaporation, and then purified by column chromatography (the eluent was a mixed solvent of ethyl acetate / benzene, and the volume ratio of the two was 4:1), and the eluent was removed by rotary evaporation to obtain intermediate 4;

[0041] S5. In a three-necked flask equipped with a stirring device, 13.4 g of terephthalaldehyde, 75.4 g of intermediate 4 and 150 mL of N,N-dimethylformamide were mixed, and the mixture was stirred vigorously. 30 mL of piperidine was added, and the reaction temperature was controlled to 70°C. The reaction was kept warm for 8 hours. After the reaction was completed, the solvent was removed by vacuum distillation, and the mixture was washed with anhydrous ethanol for 3 times. The mixture was dried in vacuo to obtain a modified diol.

[0042] Example 2

[0043] Preparation of modified diols:

[0044] S1. At room temperature, add 29.8 g tartaric acid, 17.0 g DAST and 200 mL dichloromethane into a flask, stir and mix evenly, react for 55 min, filter, take the filter cake, wash it with anhydrous ethanol for 3 times, and dry it to obtain intermediate 1;

[0045] S2. In a three-necked flask equipped with a stirring device, 31.8 g of tris(hydroxymethyl)aminomethane hydrochloride, 28.8 g of triethylamine and 200 mL of DMF were mixed at room temperature, placed in an ice-water bath at 2°C, and stirred for 45 min. Then, 31.2 g of phosphorus oxychloride was slowly added dropwise, and the temperature was controlled not to exceed 18°C ​​during the addition. After the addition was completed, the temperature was raised to 90°C and the reaction was kept warm for 10 h. After the reaction was completed, the solvent was removed by filtration under reduced pressure, and the filter cake was washed twice with anhydrous ethanol, vacuum dried, and ground to obtain intermediate 2.

[0046] S3, add 33.4g of intermediate 1 and 200mL of N,N-dimethylformamide to a three-necked flask equipped with a stirring device, heat to 45°C and stir continuously until intermediate 1 is completely dissolved; introduce nitrogen, add 33.0g of intermediate 2 and 41.2g of dicyclohexylcarbodiimide, mix and stir evenly, heat to 50°C, keep warm and react for 75min, filter after the reaction, remove the solvent by reduced pressure distillation, and vacuum dry to obtain intermediate 3;

[0047] S4, in a three-necked flask equipped with a stirring device, 20.8g of 1,3-diamino-2-propanol, 60.2g of intermediate 3 and 400mL of N,N-dimethylformamide were mixed and stirred evenly, 41.2g of dicyclohexylcarbodiimide was added, the device was placed in a water bath, and the reaction was kept at 55°C for 90min. After the reaction was completed, it was filtered, most of the solvent was removed by rotary evaporation, and then purified by column chromatography (the eluent was a mixed solvent of ethyl acetate / benzene, and the volume ratio of the two was 4:1), and the eluent was removed by rotary evaporation to obtain intermediate 4;

[0048] S5. In a three-necked flask equipped with a stirring device, 26.8 g of terephthalaldehyde, 150.8 g of intermediate 4 and 300 mL of N,N-dimethylformamide were mixed, and the mixture was stirred vigorously until uniform. 60 mL of piperidine was added, and the reaction temperature was controlled to 70°C. The reaction was kept warm for 8 hours. After the reaction was completed, the solvent was removed by distillation under reduced pressure, and the mixture was washed with anhydrous ethanol for 3 times. The mixture was dried in vacuo to obtain a modified diol.

[0049] Example 3

[0050] Under nitrogen protection, 20g MDI, 0.05g dibutyltin oxide, 30g polypropylene glycol, 10g PET, 5g modified diol prepared in Example 1 and 150g acetone were added to a three-necked flask equipped with a stirring reflux device, stirred and mixed evenly, and reacted at 40°C for 2h; 4g 1,4-butanediol was added, and the reaction was carried out at 50°C for 2h; 0.1g cyclohexanone peroxide and 8g KH-560 were added, the temperature was raised to 60°C and reacted for 4h, and then 100g deionized water was added. High-speed shear emulsification was carried out for 45min, and acetone was removed by reduced pressure rotary evaporation to obtain a waterproof spray material.

[0051] Example 4

[0052] Under nitrogen protection, 30gMDI, 0.1gdibutyltin oxide, 40gpolypropylene glycol, 15gPET, 10gmodified diol obtained in Example 2 and 175gacetone were added to a three-necked flask equipped with a stirring reflux device, stirred and mixed evenly, and reacted at 40°C for 2h; 6g1,4-butanediol was added, and the mixture was reacted at 50°C for 2h; 0.2gdibenzoyl peroxide and 12gKH-550 were added, the mixture was heated to 60°C and reacted for 4h, 150gdeionized water was added, high-speed shear emulsification was performed for 45min, and acetone was removed by vacuum rotary evaporation to obtain a waterproof spray material.

[0053] Example 5

[0054] Under nitrogen protection, 40gMDI, 0.1gdibutyltin oxide, 50gpolypropylene glycol, 20gPET, 15gmodified diol obtained in Example 2 and 200gacetone were added to a three-necked flask equipped with a stirring reflux device, stirred and mixed evenly, and reacted at 40°C for 2h; 8g1,4-butanediol was added, and reacted at 50°C for 2h; 0.3gdibenzoyl peroxide and 16gKH-550 were added, the temperature was raised to 60°C and reacted for 4h, and then 200gdeionized water was added, high-speed shear emulsification was carried out for 45min, and acetone was removed by vacuum rotary evaporation to obtain a waterproof spray material.

[0055] Comparative Example 1

[0056] The modified diol in Example 5 was replaced by propylene glycol of equal mass, and the remaining steps were the same as those in Example 5 to obtain the material.

[0057] Comparative Example 2

[0058] Use commercially available waterproof paint.

[0059] The materials of Examples 3-5 and Comparative Examples 1-2 were subjected to performance tests according to the following standards:

[0060] The national standard GB 12441-2005 "Surface fire retardant coating" was used to measure the flame retardant time and mass loss of the sample before and after 60 days of application;

[0061] The national standard GB / T 1733-1993 "Determination of water resistance of paint film" is used to determine the water resistance of the sample coating;

[0062] The wear resistance was tested by the sandpaper linear wear method. A weight of 100 g was added to the 2000-grit sandpaper. The sandpaper was moved on the coating at a constant speed of 1 cm per time. After 10 times, the water contact angle of the coating was tested before and after 60 days.

[0063] The flexibility of the coating film is measured using the national standard GB / T 1731-1993 "Determination of paint film flexibility";

[0064] The measured results are shown in the following table:

[0065]

[0066]

[0067] It can be seen from the above table that the material prepared in the embodiment of the present invention has stable and efficient flame retardancy and waterproofness, and excellent mechanical properties, and has important application value in the field of waterproof coating technology.

[0068] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0069] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A preparation process of a waterproof spray material, characterized in that: The following steps are involved: MDI, dibutyltin oxide, polypropylene glycol, PET, modified diol and acetone are stirred and mixed evenly, and reacted; 1,4-butanediol is added, and reacted; an initiator and a silane coupling agent are added, and the temperature is raised to react, and deionized water is added, high-speed shear emulsification is performed, and reduced-pressure rotary evaporation is performed to obtain a waterproof spray material; Wherein, the modified diol is prepared by the following steps: S1. Add tartaric acid, DAST and dichloromethane into a flask at room temperature, stir and mix evenly, react for 55 minutes, filter, take the filter cake, wash and dry to obtain intermediate 1; S2, tris(hydroxymethyl)aminomethane hydrochloride, triethylamine and DMF were mixed, placed in an ice water bath at 2°C, and stirred for 45 minutes, and then phosphorus oxychloride was added, and the temperature was controlled not to exceed 18°C ​​during the dropwise addition. After the dropwise addition was completed, the reaction was carried out at 90°C for 10 hours. After the reaction was completed, the mixture was filtered under reduced pressure, washed, vacuum dried, and ground to obtain intermediate 2; S3, add intermediate 1 and N,N-dimethylformamide to a three-necked flask, heat and stir continuously until intermediate 1 is completely dissolved; introduce nitrogen, add intermediate 2 and dicyclohexylcarbodiimide, mix and stir evenly, react at 50°C for 75 minutes, and after the reaction is completed, filter, distill under reduced pressure, and dry in vacuum to obtain intermediate 3; S4, 1,3-diamino-2-propanol, intermediate 3 and N,N-dimethylformamide were mixed and stirred evenly, dicyclohexylcarbodiimide was added, and the mixture was reacted at 55°C for 90 minutes. After the reaction was completed, the mixture was filtered, rotary evaporated, purified by column chromatography, and rotary evaporated to obtain intermediate 4; S5, terephthalaldehyde, intermediate 4 and N,N-dimethylformamide are mixed, vigorously stirred and uniformly mixed, piperidine is added, and the mixture is kept at 70°C for 8 hours. After the reaction is completed, vacuum distillation is performed, washing is performed, and vacuum drying is performed to obtain a modified diol; Among them, the ratio of the amount of intermediate 1, N,N-dimethylformamide, intermediate 2, and dicyclohexylcarbodiimide in step S3 is 16.7g:100mL:16.5g:20.6g; the ratio of the amount of 1,3-diamino-2-propanol, intermediate 3, N,N-dimethylformamide, and dicyclohexylcarbodiimide in step S4 is 10.4g:30.1g:200mL:20.6g; the ratio of the amount of terephthalaldehyde, intermediate 4, N,N-dimethylformamide, and piperidine in step S5 is 13.4g:75.4g:150mL:30mL.

2. The preparation process of a waterproof spray material according to claim 1, characterized in that: The raw materials are calculated in parts by weight as follows: 20-40 parts of MDI, 0.05-0.1 parts of dibutyltin oxide, 30-50 parts of polypropylene glycol, 10-20 parts of PET, 5-15 parts of modified diol, 150-200 parts of acetone, 4-8 parts of 1,4-butanediol, 0.1-0.3 parts of initiator, 8-16 parts of silane coupling agent, and 100-200 parts of deionized water.

3. The preparation process of a waterproof spray material according to claim 1, characterized in that: The usage ratio of tartaric acid, DAST and dichloromethane is 14.9 g:8.5 g:100 mL.

4. The preparation process of a waterproof spray material according to claim 1, characterized in that: The ratio of tris(hydroxymethyl)aminomethane hydrochloride, triethylamine, DMF and phosphorus oxychloride used is 15.9g:14.4g:100mL:15.6g.

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