阅读说明：本技术 一种疏水性单宁修饰聚磷腈纳米材料的制备方法及其在防火阻燃涂料中的应用 (Preparation method of hydrophobic tannin modified polyphosphazene nano material and application of hydrophobic tannin modified polyphosphazene nano material in fireproof flame-retardant coating ) 是由 王岩 于 2020-11-10 设计创作，主要内容包括：本发明属于涂料技术领域,公开了一种疏水性单宁修饰聚磷腈纳米材料的制备方法及其在防火阻燃涂料中的应用。所述聚磷腈纳米材料的制备方法包含以下步骤：(1)沉淀聚合法制备聚磷腈纳米材料：将六氯三聚磷腈和植物单宁加入乙腈中后超声处理,再加入三甲胺,超声处理后离心,清洗沉淀,干燥得产物；(2)超疏水修饰：将得到的产物放入金属盐溶液中,搅拌,过滤,干燥后放入长链硫醇化合物的醇溶液中,搅拌后过滤,醇洗,干燥得疏水性单宁修饰聚磷腈纳米材料。该聚磷腈纳米材料是通过沉淀聚合法经过单宁修饰所得,利用单宁可以与金属离子络合的性能,提高了材料的抑烟性,进一步采用长链烷基化合物对材料进行疏水修饰,提高了材料的耐水性。(The invention belongs to the technical field of coatings, and discloses a preparation method of a hydrophobic tannin modified polyphosphazene nano material and application of the hydrophobic tannin modified polyphosphazene nano material in a fireproof flame-retardant coating. The preparation method of the polyphosphazene nano material comprises the following steps: (1) preparing polyphosphazene nano material by precipitation polymerization: adding hexachlorotriphosphazene and plant tannin into acetonitrile, performing ultrasonic treatment, adding trimethylamine, performing ultrasonic treatment, centrifuging, cleaning the precipitate, and drying to obtain a product; (2) and (3) super-hydrophobic modification: and putting the obtained product into a metal salt solution, stirring, filtering, drying, putting into an alcoholic solution of a long-chain thiol compound, stirring, filtering, washing with alcohol, and drying to obtain the hydrophobic tannin modified polyphosphazene nano material. The polyphosphazene nano material is obtained by tannin modification through a precipitation polymerization method, the smoke suppression performance of the material is improved by utilizing the complexation performance of tannin and metal ions, and the water resistance of the material is improved by further adopting a long-chain alkyl compound to carry out hydrophobic modification on the material.)

1. A preparation method of a hydrophobic tannin modified polyphosphazene nano material is characterized by comprising the following steps:

(1) preparing polyphosphazene nano material by precipitation polymerization: adding hexachlorotriphosphazene and plant tannin into acetonitrile, performing ultrasonic treatment, adding trimethylamine, performing ultrasonic treatment, centrifuging, cleaning the precipitate, and drying to obtain a product;

(2) and (3) super-hydrophobic modification: and (2) putting the product obtained in the step (1) into a metal salt solution, stirring, filtering, drying, putting into an alcohol solution of a long-chain thiol compound, stirring, filtering, washing with alcohol, and drying to obtain the hydrophobic tannin modified polyphosphazene nano material.

2. The preparation method of the hydrophobic tannin-modified polyphosphazene nanomaterial as claimed in claim 1, wherein the plant tannin is one or more of catechol, gallic acid, larch tannin and myricetin; preferably, the mass ratio of the hexachlorotriphosphazene to the vegetable tannin is 3-4: 5-10; further preferably, the mass volume ratio of the plant tannin to the acetonitrile and trimethylamine is 5-10 g: 200-300 mL: 20-30 mL.

3. The preparation method of the hydrophobic tannin modified polyphosphazene nanomaterial as claimed in claim 1, wherein in the step (1), the ultrasonic treatment of the hexachlorotriphosphazene and the plant tannin after being added into acetonitrile is ultrasonic for 10-50 min; preferably, in the step (1), the ultrasonic treatment after the trimethylamine is added is ultrasonic treatment at 45-55 ℃ for 3-5 h; preferably, in the step (1), the precipitate is washed with absolute ethyl alcohol, acetone and water respectively in sequence.

4. The preparation method of the hydrophobic tannin modified polyphosphazene nanomaterial as claimed in claim 1, wherein the metal salt is one or more of ferric chloride, ferrous sulfate, cupric chloride and cobalt chloride; preferably, the molar ratio of the hexachlorotriphosphazene to the metal salt is 10: 0.28-0.36.

5. The method for preparing the hydrophobic tannin modified polyphosphazene nanomaterial as claimed in claim 1, wherein the long-chain thiol compound is one or more of n-octadecanethiol, 1-hexadecanethiol, 1-tetradecanethiol, dodecylmercaptan, octanethiol, 1-heptanethiol, 1-nonanethiol, 1-octanethiol, 2-methylbutynethiol, 3-methyl-1-butanethiol, 2-butanethiol and isooctanethiol; preferably, the long chain sulfurThe alcohol compound is one or more of 1-tetradecyl mercaptan, dodecyl mercaptan, 1-octyl mercaptan and 2-methyl butyl mercaptan; further preferably, the concentration of the alcoholic solution of the long-chain thiol compound is 1.5-2.5mg mL^-1。

6. The hydrophobic tannin modified polyphosphazene nanomaterial prepared by the preparation method of any one of claims 1 to 5.

7. The use of the hydrophobic tannin-modified polyphosphazene nanomaterial as claimed in claim 6, wherein the use is in the use of the hydrophobic tannin-modified polyphosphazene nanomaterial in fire-retardant coatings.

8. The fireproof flame-retardant coating is characterized by comprising water-based acrylic resin, a tannin modified polyphosphazene nano material, a functional filler and an auxiliary agent.

9. The fireproof flame-retardant coating according to claim 8, wherein the fireproof flame-retardant coating comprises, by weight, 30-45 parts of aqueous acrylic resin, 15-40 parts of tannin modified polyphosphazene nanomaterial, 15-30 parts of functional filler and 1-2 parts of auxiliary agent; preferably, the functional filler is one or more of titanium dioxide, expandable graphite, nano titanium dioxide and zinc oxide; preferably, the auxiliary agent is one or more of an anti-settling agent, a leveling agent, a dispersing agent and a defoaming agent.

10. The method for preparing the fireproof flame-retardant coating of any one of claims 8 to 9, wherein the method comprises the following steps: mixing the water-based acrylic resin, the tannin modified polyphosphazene nano material, the functional filler and the auxiliary agent, stirring for 30-60 minutes at the rotating speed of 900-3000 r/min after mixing, then adding grinding medium glass beads, sanding for 240-360 minutes at the rotating speed of 2000-3000r/min, filtering out the glass beads, and adjusting the viscosity to 1350 +/-50 mPa & s by using deionized water to obtain the fireproof flame-retardant coating.

Technical Field

The invention relates to the technical field of coatings, in particular to a preparation method of a hydrophobic tannin modified polyphosphazene nano material and application of the hydrophobic tannin modified polyphosphazene nano material in a fireproof flame-retardant coating.

Background

Phosphorus and nitrogen elements in polyphosphazene molecules are flame retardant elements, and as a novel organic and inorganic polymer material, phosphorus and nitrogen atoms with rich main chains endow the polyphosphazene with excellent halogen-free flame retardant property, and the polyphosphazene can reduce the heat release rate and the smoke release amount when added into a base material, and is degraded in combustionN generated in the process₂、NH₃And the like, the flammable gas concentration can be reduced by using the gas which is difficult to burn, low in toxicity and non-corrosive. In addition, the controllability of the types and the proportion of the polyphosphazene molecular side groups enables the polymer material to have various other characteristics, and in practical application, people can introduce the side groups of specific types and the proportion into a polyphosphazene chain according to specific environmental requirements, so that the polyphosphazene material is endowed with the required specific performance to meet the practical application.

Disclosure of Invention

The invention aims to overcome the defect of poor water resistance of the fireproof coating, and provides a polyphosphazene nano material modified by hydrophobic tannin, which is obtained by modifying the polyphosphazene nano material by a precipitation polymerization method through the tannin, improves the smoke suppression performance of the material by utilizing the complexation performance of the tannin and metal ions, further adopts a long-chain alkyl compound to perform hydrophobic modification on the material, improves the water resistance of the material, and can be applied to the water-based fireproof coating.

In another aspect, the invention provides a preparation method of a hydrophobic tannin modified polyphosphazene nano material, which comprises the following steps:

(1) preparing polyphosphazene nano material by precipitation polymerization: adding hexachlorotriphosphazene and plant tannin into acetonitrile, performing ultrasonic treatment, adding trimethylamine, performing ultrasonic treatment, centrifuging, cleaning the precipitate, and drying to obtain a product;

(2) and (3) super-hydrophobic modification: and (2) putting the product obtained in the step (1) into a metal salt solution, stirring, filtering, drying, putting into an alcohol solution of a long-chain thiol compound, stirring, filtering, washing with alcohol, and drying to obtain the hydrophobic tannin modified polyphosphazene nano material.

Further, the vegetable tannin is one or more of catechol, gallic acid, larch tannin and myricetin.

Preferably, in some embodiments of the present invention, the mass ratio of the hexachlorotriphosphazene to the vegetable tannin is 3-4: 5-10.

Further preferably, in some embodiments of the present invention, the plant tannin and the acetonitrile/trimethylamine in a mass to volume ratio of 5 to 10 g: 200-300 mL: 20-30 mL.

Preferably, in some embodiments of the present invention, in the step (1), the ultrasonic treatment of the hexachlorotriphosphazene and the plant tannin after adding to the acetonitrile is ultrasonic for 10-50 min.

Preferably, in some embodiments of the present invention, in the step (1), the ultrasonic treatment after the trimethylamine is added is ultrasonic treatment at 45 to 55 ℃ for 3 to 5 hours.

Preferably, in some embodiments of the present invention, in the step (1), the precipitate is washed with absolute ethanol, acetone, and water in sequence.

Further, in some embodiments of the invention, the metal salt is one or more of ferric chloride, ferrous sulfate, cupric chloride, and cobalt chloride.

Preferably, the molar ratio of the hexachlorotriphosphazene to the metal salt is 10: 0.28-0.36.

Further, the long-chain mercaptan compound is one or more of n-octadecanethiol, 1-hexadecanethiol, 1-tetradecanethiol, dodecylmercaptan, octanethiol, 1-heptanethiol, 1-nonanethiol, 1-octanethiol, 2-methylbutylthiol, 3-methyl-1-butanethiol, 2-butanethiol and isooctanethiol.

Preferably, in some embodiments of the invention, the long chain thiol compound is one or more of 1-tetradecyl mercaptan, dodecyl mercaptan, 1-octyl mercaptan, and 2-methyl-butyl mercaptan.

Further preferably, in some embodiments of the invention, the concentration of the alcoholic solution of the long-chain thiol compound is 1.5-2.5mg mL^-1。

In another aspect, the invention provides a hydrophobic tannin modified polyphosphazene nano material obtained by the method.

Further, the invention provides an application of the hydrophobic tannin modified polyphosphazene nano material, wherein the application is to use the hydrophobic tannin modified polyphosphazene nano material in a fireproof flame-retardant coating.

In another aspect, the invention also provides a fireproof flame-retardant coating, which comprises a water-based acrylic resin, a tannin modified polyphosphazene nano material, a functional filler and an auxiliary agent.

Further, the fireproof flame-retardant coating comprises, by weight, 30-45 parts of aqueous acrylic resin, 15-40 parts of tannin modified polyphosphazene nano material, 15-30 parts of functional filler and 1-2 parts of an auxiliary agent.

Further, the functional filler is one or more of titanium dioxide, expandable graphite, nano titanium dioxide and zinc oxide.

Further, the auxiliary agent is one or more of an anti-settling agent, a leveling agent, a dispersing agent and a defoaming agent.

Further, the invention also provides a preparation method of the fireproof flame-retardant coating, which comprises the following steps: mixing the water-based acrylic resin, the tannin modified polyphosphazene nano material, the functional filler and the auxiliary agent, stirring for 30-60 minutes at the rotating speed of 900-3000 r/min after mixing, then adding grinding medium glass beads, sanding for 240-360 minutes at the rotating speed of 2000-3000r/min, filtering out the glass beads, and adjusting the viscosity to 1350 +/-50 mPa & s by using deionized water to obtain the fireproof flame-retardant coating.

Compared with the prior art, the invention has the following advantages:

(1) the polyphosphazene is used as a core, the main chain of the polyphosphazene is rich in phosphorus and nitrogen atoms, so that the polyphosphazene has excellent halogen-free flame retardant property, plant polyphenol/tannin and the polyphosphazene are combined by using the designability of polyphosphazene molecules and a chemical method, the plant polyphenol contains a plurality of phenolic hydroxyl groups and can be used as a carbonizing agent, and meanwhile, a polyphenol group and metal ions can form stable chelate, so that the formation of a carbon layer is accelerated by the chelate, and the carbonization of an expansion system is promoted in a solid phase, so that the release of heat and the generation of smoke are inhibited;

(2) tannin can form a nano-scale film and is adhered to any substrate interface, which is very similar to the adhesive material of mussel, namely the adhesive force between the flame retardant and the matrix resin can be improved, and the adhesive force between the resin and the substrate is also improved to a certain extent;

(3) according to the invention, the plant polyphenol/tannin can form different forms of bonding and interaction with various groups or molecules, and low surface energy modification is carried out on the flame retardant, so that the flame retardant has hydrophobic property, and the comprehensive performance of the coating is improved;

(4) the polyphosphazene modified plant polyphenol type flame retardant disclosed by the invention can be added into a water-based fireproof coating, so that the influence of a water-soluble fireproof additive on the coating performance is reduced on the basis of ensuring the corrosion resistance of the coating, and the iron tannin and the zinc oxide can be melted in a solid phase to form a covering layer of a glass body, so that the covering layer is sealed on the surface of a product, the heat release rate is reduced, and the coating performance is improved.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. It is to be understood that the following description is only illustrative of the present invention and is not to be construed as limiting the present invention.

The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the number clearly indicates the singular.

Furthermore, the description below of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily for the same embodiment or example. Further, the technical features of the embodiments of the present invention may be combined with each other as long as they do not conflict with each other.

The coating test method comprises the following steps: the coating fire prevention and smoke test is carried out by adopting a full-automatic cone calorimeter, the size of a sample is 100 multiplied by 3mm, and fire prevention and smoke suppression indexes such as heat release rate, smoke release amount and the like are collected every 5 s.

The water resistance test method of the coating comprises the following steps: coating the paint on a steel plate, coating the paint on the steel plate in different ways until the dry film is 1.0mm, taking out the paint film after drying, sealing the edge by using rosin, immersing the paint film in a water tank, completely immersing the paint film, and observing the condition of the paint film after 24 hours.

Example 1

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 6.0g of catechol into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the resulting product was taken up in 3.2mmol L^-1In 100mL of ferric chloride solution, stirring for 4 hours, filteringAfter filtration and drying, the product was taken in 2.0mg mL^-1Stirring the mixture for 4 hours in 50mL of the alcohol solution of the dodecyl mercaptan compound, filtering, washing with alcohol, and drying to obtain the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 42g of water-based acrylic resin, 37g of tannin modified polyphosphazene nano material, 11g of titanium dioxide, 2.5g of expandable graphite, 4.5g of zinc oxide, 0.5g of anti-settling agent, 0.4g of flatting agent, 0.5g of dispersing agent and 0.6g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 0.7KW and the total smoke release quantity is 0.5m²And the layer does not appear and fall off after soaking in water for 24 hours.

Example 2

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 5g of myricetin into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the resulting product was taken up in 3.2mmol L^-1To 100mL of copper chloride solution, stirring for 4 hours, filtering, drying, and adding the product to 2.0mg mL^-1And (3) adding 1-tetradecyl mercaptan into 50mL of alcoholic solution, stirring for 4 hours, filtering, washing with alcohol, and drying to obtain the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 38g of water-based acrylic resin, 38g of tannin modified polyphosphazene nano material, 10g of titanium dioxide, 4g of expandable graphite, 2g of nano titanium dioxide, 6g of zinc oxide, 0.4g of anti-settling agent, 0.3g of flatting agent, 0.5g of dispersing agent and 0.8g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to be (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 0.9KW and the total smoke release quantity is 0.7m when tested by the method of the invention²The layer does not rise and fall off after soaking in water for 24 hours;

example 3

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 6g of gallic acid into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the resulting product was taken up in 3.2mmol L^-1Stirring for 4 hours in 100mL of ferrous sulfate solution, filtering, drying, and adding the product into 2.0mg mL^-1And (3) adding 50mL of 1-octanethiol alcohol solution, stirring for 4 hours, filtering, washing with alcohol, and drying to obtain a product, namely the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 38g of water-based acrylic resin, 35g of tannin modified polyphosphazene nano material, 12g of titanium dioxide, 3g of expandable graphite, 4g of nano titanium dioxide, 6g of zinc oxide, 0.6g of anti-settling agent, 0.4g of flatting agent, 0.4g of dispersing agent and 0.6g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to be (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 0.8KW and the total smoke release quantity is 0.8m by testing according to the method of the invention²The layer does not rise and fall off after soaking in water for 24 hours;

example 4

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 6g of larch tannin into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the resulting product was taken up in 3.2mmol L^-1Stirring for 4 hours in 100mL of cobalt chloride solution, filtering and drying to obtain the productThe resulting mixture was placed in a 2.0mg mL portion^-1And (3) adding 50mL of 2-methyl butanethiol in an alcoholic solution, stirring for 4 hours, filtering, washing with alcohol, and drying to obtain the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 35g of water-based acrylic resin, 33g of tannin modified polyphosphazene nano material, 14g of titanium dioxide, 6g of expandable graphite, 10g of zinc oxide, 0.4g of anti-settling agent, 0.4g of flatting agent, 0.5g of dispersing agent and 0.7g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 1.3KW and the total smoke release quantity is 0.9m when tested by the method of the invention²The layer does not rise and fall off after soaking in water for 24 hours;

comparative example 1

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 6.0g of catechol into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the product obtained above was taken in 2.0mg mL^-1Stirring the mixture for 4 hours in 50mL of an alcoholic solution of the dodecyl mercaptan compound, filtering, washing with alcohol, and drying to obtain the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 42g of water-based acrylic resin, 37g of tannin modified polyphosphazene nano material, 11g of titanium dioxide, 2.5g of expandable graphite, 4.5g of zinc oxide, 0.5g of anti-settling agent, 0.4g of flatting agent, 0.5g of dispersing agent and 0.6g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 2.1KW and the total smoke release quantity is 1.1m when tested by the method²And the layer does not appear and fall off after soaking in water for 24 hours.

Comparative example 2

Preparing polyphosphazene nano material by precipitation polymerization: adding 3.5g of hexachlorotriphosphazene and 6.0g of catechol into 250mL of acetonitrile, performing ultrasonic treatment for 30min, adding 25mL of trimethylamine, performing ultrasonic treatment for 4h at 50 ℃, performing centrifugal treatment, respectively cleaning precipitates with absolute ethyl alcohol, acetone and water, and drying to obtain a product.

And (3) super-hydrophobic modification: the resulting product was taken up in 3.2mmol L^-1Stirring the solution of ferric trichloride for 4 hours in 100mL of the solution of ferric trichloride, filtering and drying to obtain the tannin modified polyphosphazene nano material.

Preparation of the coating: respectively weighing 42g of water-based acrylic resin, 37g of tannin modified polyphosphazene nano material, 11g of titanium dioxide, 2.5g of expandable graphite, 4.5g of zinc oxide, 0.5g of anti-settling agent, 0.4g of flatting agent, 0.5g of dispersing agent and 0.6g of defoaming agent for later use, mixing, stirring at the rotating speed of 1000r/min for 30-60 minutes, adding grinding medium glass beads, sanding at the rotating speed of 2000 r/min-3000 r/min for 240-360 minutes, filtering out the glass beads, and adjusting the viscosity to (1350 +/-50) mPa & s by using deionized water to obtain the coating.

The total heat release quantity of the obtained coating is 1.4KW and the total smoke release quantity is 0.7m when tested by the method of the invention²And after 24 hours of soaking in water, the coating foams and falls off.

It will be understood by those skilled in the art that the foregoing is only exemplary of the present invention, and is not intended to limit the invention, which is intended to cover any variations, equivalents, or improvements therein, which fall within the spirit and scope of the invention.