Halogen-free flame-retardant polyurea protective coating and application thereof

Abstract

To address the shortcomings of existing technologies, this invention provides a halogen-free flame-retardant polyurea protective coating, comprising component A and component B. Component A is a semi-prepolymer obtained by reacting a first polyether polyol with an aromatic isocyanate. Component B, by weight, comprises: 30-50 parts of a second polyether polyol, 20-30 parts of an amine chain extender, 15-20 parts of a halogen-free flame retardant, 0.2-0.5 parts of a coupling agent, and 0.2-0.5 parts of a catalyst. This invention provides a flame-retardant polyurea protective material that can be used in the petrochemical industry, possessing excellent mechanical properties and highly efficient and environmentally friendly flame-retardant performance.

Description

Technical Field

[0001] This invention relates to the field of polymer flame retardant modification technology, and in particular to a halogen-free flame retardant polyurea protective coating and its application. Background Technology

[0002] Polyurea (PUA), as a high-performance coating, is widely used in vehicle and aircraft protection, storage tank corrosion prevention, and building waterproofing due to its excellent mechanical properties, corrosion resistance, abrasion resistance, and water resistance. Spray-applied polyurea is a coating produced by the reaction of an isocyanate component (component A) and an amino compound component (component B). Spray-applied polyurea technology combines the advantages of coatings, rubber, and plastics as anti-corrosion materials, making it one of the most advanced anti-corrosion technologies internationally. This technology uses terminal amino polyethers and amine chain extenders as active hydrogen components, which react with isocyanates to achieve rapid curing at room temperature. It offers advantages such as being solvent-free, having high mechanical strength, fast application speed, and good aging resistance.

[0003] However, polyurea itself is extremely flammable, with a limiting oxygen index (LOI) of only about 21%, and produces a large number of molten droplets and toxic fumes when burning. A large number of flammable droplets can cause burns to people and rapid spread of fire, while toxic fumes can cause asphyxiation. Therefore, it is of great significance to improve the flame retardant properties of polyurea while maintaining its excellent mechanical properties.

[0004] In existing technologies, there are two main approaches to improving the flame retardancy of sprayed polyurea materials:

[0005] One approach is to alter the chemical structure of the polyurea itself, typically by introducing flame-retardant elements such as phosphorus, nitrogen, and silicon into the polyurea molecular chain.

[0006] Second, flame retardants containing flame-retardant elements are added to polyurea materials.

[0007] The latter method offers better practicality and economy, making it a common approach for flame-retardant modification of sprayed polyurea. However, existing flame-retardant modified polyurea materials, especially polyurea coatings, still exhibit less than ideal flame-retardant effects. Furthermore, the addition of flame retardants often results in a significant reduction in mechanical properties, hindering the application of flame-retardant polyurea coatings. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a halogen-free flame-retardant polyurea protective coating, comprising component A and component B. Component A is a semi-prepolymer obtained by reacting a first polyether polyol with an aromatic isocyanate. Component B, by weight, comprises: 30-50 parts of a second polyether polyol, 20-30 parts of an amine chain extender, 31-35 parts of a halogen-free flame retardant, 0.2-0.5 parts of a coupling agent, and 0.2-0.5 parts of a catalyst.

[0009] The molecular formula of the halogen-free flame retardant is:

[0010]

[0011] Furthermore, the first polyether polyol is at least one of polytetrahydrofuran ether polyol and polyoxypropylene ether polyol. The second polyether polyol is at least one of difunctional polyether polyol and trifunctional polyether polyol.

[0012] Furthermore, the molecular weight of the first polyether polyol is 1000-2000. The molecular weight of the second polyether polyol is 1000-4000.

[0013] Furthermore, both component A and component B are liquid phase components. The volume ratio of component A to component B is 1:1.

[0014] Furthermore, the semi-prepolymer is prepared by the following method:

[0015] In an inert environment, the first polyether polyol is heated to 100-120°C in a reaction vessel while stirring.

[0016] S102 creates a negative pressure environment in the reaction vessel and maintains this negative pressure environment for a preset time.

[0017] S103 maintains a negative pressure environment, reducing the temperature of the first polyether polyol in the reaction vessel to 50-60℃.

[0018] S104 adds the required amount of isocyanate to the reaction vessel and heats the reaction system of the first polyether polyol and isocyanate to 80-90°C.

[0019] The semi-prepolymer is obtained by reacting S105 for 2-3 hours.

[0020] Furthermore, the NCO% content in the semi-prepolymer is 15-20%.

[0021] Furthermore, the halogen-free flame retardant is prepared by the following method:

[0022] S201 is prepared by dissolving 10-20 parts of p-formylphenylboronic acid and 10-15 parts of tris(hydroxymethyl)aminomethane in a solvent to obtain the first reaction system.

[0023] S202 heats the first reaction system to 65-75℃ and stirs the reaction for 40-120 minutes to obtain the second reaction system.

[0024] S203 dissolves 20-40 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a solvent and adds it dropwise to the second reaction system. The reaction temperature is maintained at 65-75℃, and the reaction is stirred for 4-8 hours to obtain the third reaction system.

[0025] S204 After filtering the third reaction system, washing it with the solvent described in S201, and drying it, the halogen-free flame retardant is obtained.

[0026] Furthermore, the solvent is anhydrous ethanol.

[0027] Furthermore, the halogen-free flame retardant is a pale yellow solid.

[0028] Furthermore, the halogen-free flame retardant accounts for 20-30% of the mass percentage in component B.

[0029] In addition, the present invention also provides an application of the above-mentioned halogen-free flame-retardant polyurea coating in the fields of storage tank protection, bulletproof coating, vehicle body protection, building waterproofing, pipeline corrosion protection and ship hull protection.

[0030] The beneficial effects of this invention are as follows: This invention provides a flame-retardant polyurea protective material that can be used in the petrochemical industry. This flame-retardant polyurea protective material has excellent mechanical properties and efficient and environmentally friendly flame-retardant properties. Its performance can reach tensile strength >14MPa, elongation at break >200%, vertical burning test reaches V-0 level, and LOI reaches more than 27%. It can be used in storage tank protection, bulletproof coating, vehicle body protection, building waterproofing, pipeline corrosion protection and ship hull protection. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the synthesis route of the halogen-free flame retardant of the present invention.

[0032] Figure 2 The TGA and DTG curves of pure PUA and Example 3 under nitrogen atmosphere are shown.

[0033] Figure 3 These are screenshots from a video of the vertical combustion test of the pure PUA and the sample in Example 3 of this invention.

[0034] Figure 4 The HRR and THR curves are for the pure PUA of this invention and the sample of Example 3.

[0035] Figure 5 The images are digital photographs and electron microscope images of the carbon residue after cone calorimetry testing, wherein: (a) is a digital photograph of the carbon residue after cone calorimetry testing of pure PUA, (b) is a digital photograph of the carbon residue after cone calorimetry testing of the sample of Example 3, and (c) is an electron microscope image of the carbon residue after cone calorimetry testing of the sample of Example 3. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Unless otherwise specified, the reagents used in this invention are all conventional test reagents or commercially available reagents, and the processing methods such as stirring, heating, washing, and drying are all conventional processing methods.

[0038] Unless otherwise specified, the weight parts mentioned in this invention refer to uniform mass parts, such as 1g, 10g, or 100g. The specific mass number corresponding to one mass part can be determined as needed and is not limited to the examples of 1g, 10g, or 100g mentioned above.

[0039] This invention provides an exemplary halogen-free flame-retardant polyurea protective coating, comprising component A and component B. Component A is a semi-prepolymer obtained by reacting a first polyether polyol with an aromatic isocyanate. Component B, by weight, comprises: 30-50 parts of a second polyether polyol, 20-30 parts of an amine chain extender, 31-35 parts of a halogen-free flame retardant, 0.2-0.5 parts of a coupling agent, and 0.2-0.5 parts of a catalyst.

[0040] The molecular formula of the halogen-free flame retardant is:

[0041]

[0042] The novel phosphorus-nitrogen synergistic halogen-free flame retardant (PTD) used in this invention has a multi-hydroxyl structure, which can effectively promote the char formation of polyurea (PUA) matrix, and has good compatibility with PUA, with little negative impact on the mechanical properties of PUA.

[0043] The present invention provides, by way of example, a first polyether polyol, which is at least one of polytetrahydrofuran ether polyol and polyoxypropylene ether polyol.

[0044] The present invention provides, by way of example, a second polyether polyol, which is at least one of difunctional polyether polyol and trifunctional polyether polyol.

[0045] The present invention provides, by way of example, a first polyether polyol having a molecular weight of 1000-2000.

[0046] The present invention provides, by way of example, a second polyether polyol having a molecular weight of 1000-4000.

[0047] This invention provides an exemplary method for preparing a semi-prepolymer corresponding to component A, comprising:

[0048] In an inert environment, the first polyether polyol is heated to 100-120°C in a reaction vessel while stirring.

[0049] S102 creates a negative pressure environment in the reaction vessel and maintains this negative pressure environment for a preset time.

[0050] S103 maintains a negative pressure environment, reducing the temperature of the first polyether polyol in the reaction vessel to 50-60℃.

[0051] S104 adds the required amount of isocyanate to the reaction vessel and heats the reaction system of the first polyether polyol and isocyanate to 80-90°C.

[0052] The semi-prepolymer is obtained by reacting S105 for 2-3 hours.

[0053] The present invention provides an example of a semi-prepolymer with an NCO percentage content of 15-20%.

[0054] This invention provides an exemplary method for preparing the above-mentioned halogen-free flame retardant, the synthetic route of which is as follows: Figure 1 As shown, it includes:

[0055] S201 is prepared by dissolving 10-20 parts of p-formylphenylboronic acid and 10-15 parts of tris(hydroxymethyl)aminomethane in a solvent to obtain the first reaction system.

[0056] S202 heats the first reaction system to 65-75℃ and stirs the reaction for 40-120 minutes to obtain the second reaction system.

[0057] S203 dissolves 20-40 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a solvent and adds it dropwise to the second reaction system. The reaction temperature is maintained at 65-75℃, and the reaction is stirred for 4-8 hours to obtain the third reaction system.

[0058] S204 After filtering the third reaction system, washing it with the solvent described in S201, and drying it, the halogen-free flame retardant is obtained.

[0059] The present invention provides an exemplary solvent, namely anhydrous ethanol.

[0060] The present invention provides an exemplary halogen-free flame retardant obtained by the above preparation method, which is a pale yellow solid.

[0061] This invention provides, by way of example, a component A and a component B, wherein both components A and B are liquid phase components. The volume ratio of components A to B is 1:1.

[0062] The present invention provides an exemplary amount of halogen-free flame retardant, wherein the halogen-free flame retardant accounts for 20-30% of the mass percentage of component B.

[0063] Within this addition range, the halogen-free flame retardant can enable the polyurea coating obtained by this invention to have better flame retardant and mechanical properties.

[0064] This invention provides an exemplary application method for the halogen-free flame-retardant polyurea protective coating obtained by this invention, including: for storage tank protection, bulletproof coating, vehicle body protection, building waterproofing, pipeline corrosion protection and ship hull protection.

[0065] The technical effects of the present invention will be further explained below with reference to specific embodiments.

[0066] Example 1

[0067] A halogen-free flame-retardant polyurea protective coating is prepared by the following method:

[0068] (1) Preparation of component A:

[0069] Under inert conditions, 48 ​​parts of polyoxypropylene ether polyol with a molecular weight of 2000 are heated to 100-120°C and dehydrated under vacuum pressure (-0.1MPa) for at least 1 hour until no bubbles are generated. Then, the temperature is lowered to 50-60°C and 26 parts of isocyanate MDI-50 and 26 parts of isocyanate MDI-100 are added. The mixture is reacted at 80-90°C for 2-3 hours to obtain semi-prepolymer component A.

[0070] (2) Preparation of component B:

[0071] Component B is obtained by dispersing and stirring 41 parts of polyoxypropylene ether polyol with a molecular weight of 2000, 22 parts of 3,5-dimethylthiotoluene diamine, 4 parts of N,N-dialkyltoluene diamine, 29 parts of novel halogen-free flame retardant PTD, 0.5 parts of coupling agent and 0.5 parts of catalyst evenly, and then filtering.

[0072] (3) Preparation of halogen-free flame-retardant polyurea protective coating:

[0073] The halogen-free flame-retardant polyurea protective coating can be prepared by spraying the above components A and B in a volume ratio of 1:1 using a high-pressure airless spraying device.

[0074] Example 2

[0075] A halogen-free flame-retardant polyurea protective coating is prepared by the following method:

[0076] (1) Preparation of component A:

[0077] Under inert conditions, 48 ​​parts of polyoxypropylene ether polyol with a molecular weight of 2000 are heated to 100-120°C and dehydrated under vacuum pressure (-0.1MPa) for at least 1 hour until no bubbles are generated. Then, the temperature is lowered to 50-60°C and 26 parts of isocyanate MDI-50 and 26 parts of isocyanate MDI-100 are added. The mixture is reacted at 80-90°C for 2-3 hours to obtain semi-prepolymer component A.

[0078] (2) Preparation of component B:

[0079] Component B is obtained by dispersing and stirring 41 parts of polyoxypropylene ether polyol with a molecular weight of 2000, 22 parts of 3,5-dimethylthiotoluene diamine, 4 parts of N,N-dialkyltoluene diamine, 31 parts of novel halogen-free flame retardant PTD, 0.5 parts of coupling agent and 0.5 parts of catalyst evenly, and then filtering.

[0080] (3) Preparation of halogen-free flame-retardant polyurea protective coating:

[0081] The halogen-free flame-retardant polyurea protective coating can be prepared by spraying the above components A and B in a volume ratio of 1:1 using a high-pressure airless spraying device.

[0082] Example 3

[0083] A halogen-free flame-retardant polyurea protective coating is prepared by the following method:

[0084] (1) Preparation of component A:

[0085] Under inert conditions, 48 ​​parts of polyoxypropylene ether polyol with a molecular weight of 2000 are heated to 100-120°C and dehydrated under vacuum pressure (-0.1MPa) for at least 1 hour until no bubbles are generated. Then, the temperature is lowered to 50-60°C and 26 parts of isocyanate MDI-50 and 26 parts of isocyanate MDI-100 are added. The mixture is reacted at 80-90°C for 2-3 hours to obtain semi-prepolymer component A.

[0086] (2) Preparation of component B:

[0087] Component B is obtained by dispersing and stirring 41 parts of polyoxypropylene ether polyol with a molecular weight of 2000, 22 parts of 3,5-dimethylthiotoluene diamine, 4 parts of N,N-dialkyltoluene diamine, 33 parts of novel halogen-free flame retardant PTD, 0.5 parts of coupling agent and 0.5 parts of catalyst evenly, and then filtering.

[0088] (3) Preparation of halogen-free flame-retardant polyurea protective coating:

[0089] The halogen-free flame-retardant polyurea protective coating can be prepared by spraying the above components A and B in a volume ratio of 1:1 using a high-pressure airless spraying device.

[0090] Comparative Example

[0091] A polyurea coating is prepared by the following method:

[0092] (1) Preparation of component A:

[0093] Under inert conditions, 48 ​​parts of polyoxypropylene ether polyol with a molecular weight of 2000 are heated to 100-120°C and dehydrated under vacuum pressure (-0.1MPa) for at least 1 hour until no bubbles are generated. Then, the temperature is lowered to 50-60°C and 26 parts of isocyanate MDI-50 and 26 parts of isocyanate MDI-100 are added. The mixture is reacted at 80-90°C for 2-3 hours to obtain semi-prepolymer component A.

[0094] (2) Preparation of component B:

[0095] 41 parts of polyoxypropylene ether polyol with a molecular weight of 2000, 22 parts of 3,5-dimethylthiotoluene diamine, 4 parts of N,N-dialkyltoluene diamine, 0.5 parts of coupling agent and 0.5 parts of catalyst were dispersed and stirred evenly, and then filtered to obtain component B.

[0096] (3) Preparation of polyurea coating:

[0097] The above components A and B are sprayed using a high-pressure airless spraying device at a volume ratio of 1:1 to obtain the pure PUA.

[0098] Performance testing and results

[0099] The prepared polyurea coating / halogen-free flame-retardant polyurea protective coating was subjected to routine mechanical and flammability tests, which were conducted according to the following standards:

[0100] Tensile strength: Tested according to ASTM D 638-2010 standard at a test speed of 500 mm / min.

[0101] Thermal stability: Thermogravimetric analysis was performed in accordance with the provisions of GB / T 27761-2011.

[0102] Combustion performance: LOI standard test according to ASTM D2863, UL-94 standard test according to ASTM D3801. Cone calorimetry test at 35 kW / m² power according to ISO 5660–1.

[0103] Figure 2The TGA and DTG curves for Example 3 and the comparative example under nitrogen atmosphere show that for pure PUA, decomposition mainly occurs in the temperature range of 300°C to 450°C, with a very high decomposition rate and a maximum thermal degradation rate (DTGmax) of 1.48% / °C. At 800°C, the residual carbon content is only 0.1%, indicating that PUA is a polymer that is difficult to char.

[0104] Compared to pure PUA, Example 3 showed a lower initial decomposition temperature (T5%), indicating that the PTD flame retardant promoted the decomposition of the PUA matrix in the early stages of thermal degradation. However, Example 3 exhibited a significantly increased char residue at 800°C. This improved charring properties imply enhanced crosslinking and charring in the condensed phase throughout the combustion process, reducing combustibles and suppressing dripping. Furthermore, Example 3 showed a 37.2% reduction in DTGmax, indicating that the presence of PTD delayed the pyrolysis of PUA segments in the later stages of thermal degradation (after 350°C).

[0105] Figure 3 The video screenshots of the vertical combustion test of pure PUA and the sample of Example 3 are shown. The specific combustion conditions are shown in Table 1. The LOI value of pure PUA is only 22.1%. In the vertical combustion test, it will produce a large amount of molten droplets and smoke and ignite the degreased cotton, with a rating of only V-2. In contrast, the LOI of Example 3 is increased to 27.8%, the molten droplet phenomenon is completely eliminated and reaches the V-0 rating.

[0106] Cone calorimetry is an effective method for simulating the combustion behavior of polymers under real fire conditions. Figure 4 As can be seen, pure PUA is an extremely flammable polymer, with a peak heat release rate (pHRR) and total heat release (THR) as high as 1080.6 kW / m² and 154.7 MJ / m², respectively. Compared with pure PUA, the pHRR and THR values ​​of Example 3 were reduced by 31.0% and 52.9%, respectively, indicating that the PTD flame retardant can effectively improve the flame retardancy of PUA.

[0107] Figure 5 These are digital photographs and electron microscope images of the char residue after cone calorimetry testing of pure PUA and the sample from Example 3. It can be seen that the PUA char residue was completely burned, with virtually no char residue formed, while the sample from Example 3 formed a dense and continuous char layer after combustion. Figure 5 (b) Furthermore, under an electron microscope, the surface of the residual char was observed to be dense and without pores. This typical continuous char layer helps to suppress the release of combustible gases and the diffusion of external oxygen into the matrix during the combustion process, thereby reducing the decomposition of PUA and the release of heat.

[0108] The results of vertical combustion and limiting oxygen index (LOI) tests for Examples 1-3 and the comparative examples are shown in Table 1:

[0109] Table 1. Vertical combustion and LOI test results.

[0110]

[0111] The results of mechanical property tests on Examples 1-3 and the comparative examples are shown in Table 2:

[0112] Table 2. Mechanical property test results.

[0113] Examples / Comparative Examples Tensile strength (MPa) Elongation at break (%) Example 1 16.1 290.8 Example 2 15.5 273.3 Example 3 14.3 245.1 Comparative Example 18.8 334.6

[0114] Table 2 shows the tensile strength and elongation at break test results of pure PUA and PUA flame retardant coating. The tensile strength and elongation at break of pure PUA are 18.8 MPa and 334.6%, respectively. As the amount of PTD flame retardant added increases, the mechanical properties of the material gradually decrease. The tensile strength and elongation at break of Example 3 decrease to 14.3 MPa and 245.1%, respectively, but still have excellent mechanical properties and can meet the requirements of most commercial applications.

[0115] As shown in Table 1, combined with the above-mentioned thermogravimetric analysis, cone calorimetry, and residual carbon electron microscopy, compared with traditional flame retardants, the novel phosphorus-nitrogen synergistic PTD flame retardant synthesized in this invention has a multi-hydroxyl structure, which can effectively promote the char formation of the PUA matrix, and has good compatibility with PUA, with minimal negative impact on the mechanical properties of polyurea. The finally obtained halogen-free flame-retardant polyurea protective coating has excellent mechanical properties and highly efficient and environmentally friendly flame-retardant properties, with a tensile strength >14MPa and an elongation at break >200%. It exhibits low heat release during combustion, achieves a UL-94V-0 flame-retardant rating, produces no dripping during combustion, and has an oxygen index of over 27%.

[0116] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A halogen-free flame-retardant polyurea protective coating, comprising component A and component B, characterized in that, Component A is a semi-prepolymer prepared by reacting a first polyether polyol with an aromatic isocyanate. By weight, component B comprises: 30-50 parts of second polyether polyol, 20-30 parts of amine chain extender, 31-35 parts of halogen-free flame retardant, 0.2-0.5 parts of coupling agent, and 0.2-0.5 parts of catalyst. The molecular formula of the halogen-free flame retardant is: 。 2. The halogen-free flame-retardant polyurea protective coating according to claim 1, characterized in that, The first polyether polyol is at least one of polytetrahydrofuran ether polyol and polyoxypropylene ether polyol; the second polyether polyol is at least one of difunctional polyether polyol and trifunctional polyether polyol.

3. The halogen-free flame-retardant polyurea protective coating according to claim 2, characterized in that, The molecular weight of the first polyether polyol is 1000-2000; the molecular weight of the second polyether polyol is 1000-4000.

4. The halogen-free flame-retardant polyurea protective coating according to any one of claims 1-3, characterized in that, Both component A and component B are liquid phase components; the volume ratio of component A to component B is 1:

1.

5. The halogen-free flame-retardant polyurea protective coating according to claim 2, characterized in that, The semi-prepolymer was prepared by the following method: S101 In an inert environment, the first polyether polyol is heated to 100-120°C in a reaction vessel while maintaining stirring; S102 creates a negative pressure environment in the reaction vessel and maintains this negative pressure environment for a preset time; S103 maintains a negative pressure environment to reduce the temperature of the first polyether polyol in the reaction vessel to 50-60℃; S104 Add the required amount of isocyanate to the reaction vessel and heat the reaction system of the first polyether polyol and isocyanate to 80-90°C; The semi-prepolymer is obtained by reacting S105 for 2-3 hours.

6. The halogen-free flame-retardant polyurea protective coating according to any one of claims 1 or 5, characterized in that, The NCO% in the semi-prepolymer is 15-20%.

7. The halogen-free flame-retardant polyurea protective coating according to claim 1, characterized in that, The halogen-free flame retardant is prepared by the following method: S201 According to the mass fraction, 10-20 parts of p-formylphenylboronic acid and 10-15 parts of tris(hydroxymethyl)aminomethane are dissolved in a solvent to obtain the first reaction system; S202 Heat the first reaction system to 65-75℃ and stir for 40-120 min to obtain the second reaction system; S203 Dissolve 20-40 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a solvent and add it dropwise to the second reaction system. Maintain the reaction temperature at 65-75℃ and continue stirring for 4-8 hours to obtain the third reaction system. S204 After filtering the third reaction system, washing it with the solvent described in S201, and drying it, the halogen-free flame retardant is obtained.

8. The halogen-free flame-retardant polyurea protective coating according to claim 7, characterized in that, The solvent is anhydrous ethanol.

9. The halogen-free flame-retardant polyurea protective coating according to any one of claims 1 or 7, characterized in that, The halogen-free flame retardant accounts for 20-30% of component B by mass percentage.

10. The application of a halogen-free flame-retardant polyurea protective coating according to any one of claims 1-9 in the fields of storage tank protection, bulletproof coating, vehicle body protection, building waterproofing, pipeline corrosion protection and ship hull protection.

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