阅读说明：本技术 一种特氟龙涂覆金属网及其制备方法 (Teflon coated metal net and preparation method thereof ) 是由 骆劲松 于 2021-09-26 设计创作，主要内容包括：本申请涉及金属制品技术领域,具体公开了一种特氟龙涂覆金属网及其制备方法。所述特氟龙涂覆金属网包括金属网基体以及特氟龙涂层,所述金属网基体为经过碱溶液浸泡处理的金属网基体,所述特氟龙涂层由涂膜液在金属网基体表面受热固化后形成,所述涂膜液的配方中包括如下重量份的组分：特氟龙粉40-60份,过硫酸盐16-24份,去离子水120-140份,乳化剂8-12。本申请使用碱溶液对金属网基体进行预处理,并且通过过硫酸盐提高了特氟龙粉的活性,有助于提高特氟龙涂层与金属网基体之间的结合度,延长了特氟龙涂层的使用寿命。(The application relates to the technical field of metal products, and particularly discloses a teflon coated metal mesh and a preparation method thereof. The Teflon coating metal net comprises a metal net substrate and a Teflon coating, wherein the metal net substrate is soaked in an alkali solution, the Teflon coating is formed by heating and curing a coating liquid on the surface of the metal net substrate, and the coating liquid comprises the following components in parts by weight: 40-60 parts of Teflon powder, 16-24 parts of persulfate, 120-140 parts of deionized water and 8-12 parts of emulsifier. This application uses the alkali solution to carry out the preliminary treatment to the metal mesh base member to improved the activity of teflon powder through the persulfate, helped improving the conjugation degree between teflon coating and the metal mesh base member, prolonged the life of teflon coating.)

1. The Teflon-coated metal mesh is characterized by comprising a metal mesh substrate and a Teflon coating, wherein the metal mesh substrate is soaked in an alkali solution, the Teflon coating is formed by heating and curing a coating liquid on the surface of the metal mesh substrate, and the coating liquid comprises the following components in parts by weight: 40-60 parts of Teflon powder, 16-24 parts of persulfate, 120-140 parts of deionized water and 8-12 parts of emulsifier.

2. The teflon-coated metal mesh according to claim 1, wherein the coating solution comprises the following components in parts by weight: 45-55 parts of Teflon powder, 18-22 parts of persulfate, 135 parts of deionized water 125-11 parts of emulsifier.

3. The teflon-coated metal mesh of claim 1, wherein the coating solution further comprises 6-10 parts of a carbonization aid in the formula, and the carbonization aid comprises the following raw materials in parts by weight: 70-90 parts of bagasse and 12-16 parts of phosphoric acid, wherein the water content of the bagasse is 58-66%.

4. The teflon-coated metal mesh of claim 3, wherein the preparation method of the charring assistant comprises the following steps:

(1) mixing bagasse and acetone according to a ratio of 1: (12-16) uniformly mixing the components in a weight ratio to obtain bagasse dispersion liquid;

(2) adding phosphoric acid into bagasse dispersion liquid, heating for 2-3h at 50-65 ℃, and then evaporating to remove acetone to obtain the carbonization auxiliary agent.

5. The teflon-coated metal mesh of claim 4, wherein the formulation of the charring aid further comprises 8-12 parts of phosphorus oxychloride.

6. The teflon-coated metal mesh of claim 3, wherein the formulation of the coating solution further comprises 16-24 parts by weight of ferrous chloride.

7. The teflon-coated metal mesh of claim 6, wherein the formulation of the coating solution further comprises 6-10 parts by weight of hydrogen peroxide.

8. The teflon-coated metal mesh of claim 1, wherein the coating solution further comprises 8-12 parts by weight of a silane coupling agent.

9. The teflon-coated metal mesh of claim 8, wherein the silane coupling agent has at least one carbon-carbon double bond in a molecule.

10. A process for the preparation of a teflon coated metal mesh according to any of the claims 1-9, characterized in that it comprises the following steps:

(1) deoiling and derusting the surface of the metal mesh matrix, and then cleaning and drying the metal mesh matrix;

(2) soaking the metal net in an alkali solution for 18-24h, and then drying the metal net matrix;

(3) weighing Teflon powder, persulfate, deionized water and an emulsifier according to the weight parts, and uniformly mixing to obtain a coating liquid;

(4) coating the coating liquid on the surface of the metal mesh substrate according to the consumption of 140 plus 180ml of the coating liquid per kilogram of the metal mesh substrate, then carrying out heat treatment on the metal mesh substrate at the temperature of 350 plus 380 ℃, wherein the heat treatment time is 2-3h, and obtaining the Teflon coated metal mesh after the heat treatment is finished.

Technical Field

The application relates to the technical field of metal products, in particular to a teflon coated metal net and a preparation method thereof.

Background

Teflon is a different name of polytetrafluoroethylene, and hydrogen atoms in molecules of the Teflon are all replaced by fluorine atoms, so that the Teflon has the characteristic of corrosion resistance, and is an ideal material for processing a metal surface coating.

In the related art, a teflon coated metal mesh comprises a metal mesh substrate and a teflon coating, wherein the teflon coating is formed by heating and curing a coating liquid on the surface of the metal mesh substrate, and the coating liquid comprises the following components in parts by weight: 40-60 parts of Teflon powder, 120-140 parts of deionized water, 8-12 parts of an emulsifier, 20-40 parts of a binder, wherein the binder is polyvinyl alcohol. The preparation method of the teflon coated metal mesh comprises the following steps: (1) deoiling and derusting the surface of the metal net, and then carrying out sand blasting treatment on the surface of the metal net; (2) weighing Teflon powder, deionized water, an emulsifier and a binder according to the parts by weight to obtain a coating liquid; (3) and (3) coating the surface of the metal mesh subjected to sand blasting with a coating solution, then carrying out heat treatment on the metal mesh substrate at the temperature of 350-380 ℃, wherein the heat treatment time is 2-3h, and obtaining the Teflon coated metal mesh after the heat treatment is finished. In the heat treatment process, the Teflon parts are melted and converted into Teflon coatings, and the Teflon coatings are attached to the surface of the metal mesh substrate subjected to sand blasting and play a role in protecting the metal mesh substrate.

In view of the above-mentioned related art, the inventors believe that the teflon coating layer, although having an effect of protecting the metal mesh substrate, is easily detached from the metal mesh substrate surface due to the low surface energy of the teflon molecules, resulting in a limitation in the service life of the teflon-coated metal mesh.

Disclosure of Invention

In the related technology, the Teflon coating is easy to fall off, and the service life of the Teflon coated metal mesh is influenced. To ameliorate this drawback, the present application provides a teflon coated metal mesh and a method of making the same.

In a first aspect, the present application provides a teflon coated metal mesh, which adopts the following technical scheme:

a Teflon coated metal mesh comprises a metal mesh substrate and a Teflon coating, wherein the metal mesh substrate is soaked in an alkali solution, the Teflon coating is formed by heating and curing a coating liquid on the surface of the metal mesh substrate, and the coating liquid comprises the following components in parts by weight: 40-60 parts of Teflon powder, 16-24 parts of persulfate, 120 parts of deionized water and 140 parts of emulsifier, 8-12 parts of emulsifier

By adopting the technical scheme, compared with the related technology, the method has the advantages that the metal mesh substrate is pretreated by using the alkali solution, and the formula system of the coating solution is changed. Hydroxyl is grafted on the surface of the metal mesh substrate soaked by the alkali solution, and a part of alkaline substances are remained. After the coating liquid is coated on the surface of the metal mesh substrate, persulfate is activated by alkaline substances remained on the surface of the metal mesh substrate and decomposed to generate sulfate radicals. The sulfate radical can make the hydroxyl radical fall off from the surface of the metal net matrix to generate hydroxyl radical and form activating site on the surface of the metal net matrix. The hydroxyl free radicals attack fluorine atoms on the surface of the Teflon powder, so that carbon-fluorine bonds on the surface of the Teflon powder are broken, the reaction activity of the Teflon powder is improved, and the Teflon powder is grafted on active sites on the surface of the metal mesh substrate to form a Teflon coating. In the process of curing the coating liquid, the persulfate, the Teflon powder and the metal mesh substrate soaked by the alkali solution generate a synergistic effect, so that the combination degree between the Teflon coating and the metal mesh substrate is increased, the possibility of falling off of the Teflon coating is reduced, and the service life of the Teflon coating is prolonged.

Preferably, the formula of the coating liquid comprises the following components in parts by weight: 45-55 parts of Teflon powder, 18-22 parts of persulfate, 135 parts of deionized water 125-11 parts of emulsifier.

By adopting the technical scheme, the formula of the coating liquid is optimized, the combination degree between the Teflon coating and the metal mesh substrate is improved, and the service life of the Teflon coating is prolonged.

Preferably, the formula of the coating solution also comprises 6-10 parts of a carbonization auxiliary agent, and the carbonization auxiliary agent comprises the following raw materials in parts by weight: 70-90 parts of bagasse and 12-16 parts of phosphoric acid, wherein the water content of the bagasse is 58-66%.

By adopting the technical scheme, the bagasse mainly comprises cellulose, and the cellulose can react with phosphoric acid to generate cellulose phosphate. When the coating liquid contacts the metal mesh substrate, alkaline substances remained on the surface of the metal mesh substrate enable a part of phosphate groups in the cellulose phosphate to fall off, and cellulose residues and phosphoric acid are generated. In the process of heating and curing the coating liquid, the concentration of phosphoric acid is gradually increased, and the carbonization type of the phosphoric acid is gradually enhanced. The phosphoric acid with the increased concentration carbonizes the cellulose residue and the Teflon powder attacked by the free radicals, the carbonized part of the Teflon powder is combined with the carbonized cellulose residue to generate carbonized particles, and the carbonized particles and the Teflon powder are jointly cured to form the Teflon coating. The density of the Teflon coating is increased by the carbonized particles, and the corrosion resistance of the Teflon coating is improved. In addition, the residual phosphate groups at the un-carbonized parts of the cellulose phosphate molecules can form a chelate with the metal mesh substrate, so that the bonding degree between the Teflon coating and the metal mesh substrate is enhanced, and the service life of the Teflon coating is prolonged.

Preferably, the preparation method of the carbonization aid comprises the following steps:

(1) mixing bagasse and acetone according to a ratio of 1: (12-16) uniformly mixing the components in a weight ratio to obtain bagasse dispersion liquid;

(2) adding phosphoric acid into bagasse dispersion liquid, heating for 2-3h at 50-65 ℃, and then evaporating to remove acetone to obtain the carbonization auxiliary agent.

By adopting the technical scheme, the bagasse dispersion liquid is prepared, so that the dispersion degree of the bagasse is improved, the cellulose phosphate is favorably formed, the acetone is favorable for inhibiting the carbonization activity of the phosphoric acid, and the possibility that the bagasse is directly carbonized by the phosphoric acid is reduced.

Preferably, the formula of the carbonization auxiliary agent also comprises 8-12 parts of phosphorus oxychloride.

By adopting the technical scheme, a part of hydroxyl groups in cellulose molecules do not have esterification activity, and phosphorus oxychloride can capture hydrogen atoms in three hydroxyl groups at most and convert the hydrogen atoms into phosphate groups, so that the content of the phosphate groups in the cellulose phosphate is increased, a chelate is formed between the cellulose phosphate and a metal mesh substrate, and the binding degree between the Teflon coating and the metal mesh substrate is increased.

Preferably, the formula of the coating liquid also comprises 16-24 parts by weight of ferrous chloride.

By adopting the technical scheme, the ferrous chloride is ionized in the coating liquid to generate ferrous ions, and the ferrous ions can react with persulfate to promote the generation of sulfate radicals, thereby being beneficial to improving the combination degree between the Teflon coating and the metal mesh substrate. In addition, both ferrous ions and iron ions generated by activating persulfate through the ferrous ions can react with free phosphate groups to generate precipitates, so that the phosphorus content of the coating liquid waste liquid is reduced, and the pollution of the coating liquid waste liquid to the environment is reduced.

Preferably, the formula of the coating liquid also comprises 6-10 parts of hydrogen peroxide by weight.

By adopting the technical scheme, when the coating liquid is heated, the hydrogen peroxide can be cracked to generate hydroxyl radicals, so that the rate of the hydroxyl radicals attacking fluorine atoms is increased, the activity of Teflon molecules and the combination degree between the Teflon coating and the metal mesh substrate are increased, and the service life of the Teflon coating is prolonged.

Preferably, the coating liquid formula also comprises 8-12 parts by weight of silane coupling agent.

By adopting the technical scheme, the silane coupling agent is hydrolyzed in water to generate silanol groups, the silanol groups can be condensed with hydroxyl on the surface of the metal mesh substrate, and the hydrophobicity of the metal mesh substrate is increased, so that the compatibility between the metal mesh substrate and the Teflon coating is improved, and the service life of the Teflon coating is prolonged. In addition, the silanol group can be grafted with the Teflon molecules losing fluorine atoms, so that the combination degree between the Teflon coating and the metal mesh substrate is increased, and the service life of the Teflon coating is prolonged.

Preferably, the silane coupling agent contains at least one carbon-carbon double bond in the molecule.

By adopting the technical scheme, in the coating liquid, hydroxyl radicals and carbon-carbon double bonds are subjected to addition reaction to generate hydroxyl, the newly generated hydroxyl is condensed with silanol groups generated by hydrolysis of a silane coupling agent, the silane coupling agent is mutually crosslinked to generate a hydrophobic network structure, and the hydrophobic network structure and Teflon powder are jointly cured to generate the Teflon coating. The hydrophobic network structure not only increases the compatibility of the metal mesh substrate and the Teflon coating, but also improves the combination degree between the Teflon coating and the metal mesh substrate, thereby prolonging the service life of the Teflon coating.

In a second aspect, the present application provides a method for preparing a teflon-coated metal mesh, which adopts the following technical scheme.

A preparation method of a Teflon coated metal net comprises the following steps:

(1) deoiling and derusting the surface of the metal mesh matrix, and then cleaning and drying the metal mesh matrix;

(2) soaking the metal mesh substrate in an alkali solution for 18-24h, and then drying the metal mesh substrate;

(3) weighing Teflon powder, persulfate, deionized water and an emulsifier according to the weight parts, and uniformly mixing to obtain a coating liquid;

(4) coating the coating liquid on the surface of the metal mesh substrate according to the consumption of 140 plus 180ml of the coating liquid per kilogram of the metal mesh substrate, then carrying out heat treatment on the metal mesh substrate at the temperature of 350 plus 380 ℃, wherein the heat treatment time is 2-3h, and obtaining the Teflon coated metal mesh after the heat treatment is finished.

By adopting the technical scheme, compared with the related technology, the method does not need to carry out sand blasting treatment on the metal mesh substrate, so that the damage to the metal mesh substrate is reduced, and the teflon coated metal mesh can be obtained by melting teflon powder through heat treatment after coating the film coating liquid.

In summary, the present application has the following beneficial effects:

1. the persulfate of this application produces the sulfate radical in the ionization of coating liquid, the sulfate radical free radical that persulfate decomposed the production turns into hydroxyl free radical with the hydroxyl on metal mesh substrate surface, and produce the activation site on metal mesh substrate surface, hydroxyl free radical then attacks the fluorine atom in the teflon powder, make the fracture of carbon fluorine bond, the activity of teflon powder has been improved, help improving the conjugation degree between teflon coating and the metal mesh substrate, the life of teflon coating has been prolonged.

2. In the application, the molecule of the preferred silane coupling agent at least contains one carbon-carbon double bond, the carbon-carbon double bond and hydroxyl radical generate addition reaction, and the generated hydroxyl is condensed with silanol group generated by another silane coupling agent to form a hydrophobic network structure. The hydrophobic network structure not only increases the compatibility of the metal mesh substrate and the Teflon coating, but also improves the combination degree between the Teflon coating and the metal mesh substrate, thereby prolonging the service life of the Teflon coating.

3. According to the method, a metal mesh substrate is soaked by using a sodium hydroxide solution, then a coating solution is coated on the surface of the metal mesh substrate, and a Teflon coated metal mesh is obtained after the landscape of the coating solution is heated and cured. The metal mesh substrate does not need to be subjected to sand blasting in the treatment process, so that the damage to the metal mesh substrate is reduced.

Detailed Description

The present application will be described in further detail with reference to examples.

Preparation example of charring auxiliary

The raw materials used in the preparation examples of the present application are all commercially available, wherein bagasse from Wuming county Xin is sold by Ming's department of agricultural waste (ground to an average particle size of 80 μm), acetone is purchased from Nanjing Zhenmu chemical industry Co., Ltd, phosphoric acid is industrial orthophosphoric acid sold by Shandong Hongyun chemical science and technology Co., Ltd, and phosphorus oxychloride is industrial phosphorus oxychloride sold by Shandong An chemical industry Co., Ltd.

The following will explain preparation example 1 as an example.

Preparation example 1

In the preparation example, the carbonization aid is prepared according to the following method:

(1) uniformly mixing 70kg of bagasse with the water content of 63% with 980kg of acetone to obtain bagasse dispersion liquid;

(2) 12kg of phosphoric acid is added into the bagasse dispersion liquid, the mixture is heated for 2.5h at 58 ℃, and then acetone is removed by evaporation to obtain the carbonization aid.

As shown in Table 1, the preparation examples 1 to 5 were different in the raw material ratio of the auxiliary for carbonization.

TABLE 1

Sample(s)	Bagasse/kg	Phosphoric acid/kg
			Preparation example 1	70	12
Preparation example 2	75	13
			Preparation example 3	80	14
Preparation example 4	85	15
			Preparation example 5	90	16

Preparation example 6

The difference between the preparation example and the preparation example 1 is that the formula of the carbonization auxiliary agent also comprises 8kg of phosphorus oxychloride, and the phosphorus oxychloride is mixed with the bagasse dispersion liquid in the step (2).

As shown in Table 2, production examples 6 to 10 were different in the amount of phosphorus oxychloride used.

TABLE 2

Sample(s)	Preparation example 6	Preparation example 7	Preparation example 8	Preparation example 9	Preparation example 10
						Phosphorus oxychloride per kg	8	9	10	11	12

Examples

The raw materials used in the embodiment of the application can be obtained through the market, wherein the teflon powder is DuPont teflon powder (brand CD097E) sold by Shanghai Xinyun International trade company Limited, the persulfate is industrial sodium persulfate sold by Shandong Zorre chemical company Limited, the deionized water is JC-01 type deionized water sold by Shanghai Jing pure water treatment technology Limited, the emulsifier is Tween 60 produced by Jiangsu Pulex Biotechnology Limited, the ferrous chloride is industrial ferrous chloride (200 meshes) produced by Jiangsu Rufeng synthetic technology Limited, the hydrogen peroxide is electronic hydrogen peroxide produced by Hangzhou Xin chemical technology Limited, the methyltriethoxysilane is purchased from Wuhan Huake Jieke Biotechnology Limited, and the vinyltriethoxysilane is purchased from Shandong Polychem Limited.

Examples 1 to 5

The following description will be given by taking example 1 as an example.

Example 1

The teflon coated metal mesh of example 1 was prepared according to the following procedure:

(1) deoiling and derusting the surface of the metal mesh matrix, and then cleaning and drying the metal mesh matrix;

(2) soaking the metal net in an alkali solution for 20 hours, and then drying the metal net matrix;

(3) uniformly mixing 40kg of teflon powder, 16kg of sodium persulfate, 120kg of deionized water and 8kg of emulsifier to obtain a coating liquid;

(4) coating the coating liquid on the surface of the metal mesh substrate according to the consumption of 150ml of the coating liquid per kilogram of the metal mesh substrate, then carrying out heat treatment on the metal mesh substrate at 370 ℃, wherein the heat treatment time is 2.6h, and obtaining the Teflon coated metal mesh after the heat treatment is finished.

As shown in Table 3, examples 1 to 5 differ mainly in the raw material ratio of the coating solutions.

TABLE 3

Sample(s)	Teflon powder/kg	Sodium persulfate/kg	Deionized water/kg	Emulsifier/kg
					Example 1	40	16	120	8
Example 2	45	18	125	9
					Example 3	50	20	130	10
Example 4	55	22	135	11
					Example 5	60	24	140	12

Example 6

The difference between the embodiment and the embodiment 3 is that the coating solution further comprises 6-10 parts of a carbonization aid in the formula, and the carbonization aid is selected from the carbonization aids in the preparation example 1.

As shown in Table 4, example 3 is different from examples 6 to 15 mainly in the preparation examples of the charring assistant.

TABLE 4

Example 16

The difference between this example and example 13 is that the formulation of the coating solution further includes 16kg of ferrous chloride, and the ferrous chloride is mixed with deionized water in the step (3) of preparing teflon coated metal mesh.

As shown in Table 5, examples 16-20 differ in the amount of ferrous chloride used.

TABLE 5

Example 21

This example differs from example 18 in that the formulation of the coating solution also included 6kg of hydrogen peroxide, which was co-mixed with deionized water in step (3) of preparing the teflon coated metal mesh.

As shown in Table 6, examples 21 to 25 differ in the amount of hydrogen peroxide used.

TABLE 6

Sample(s)	Example 21	Example 22	Example 23	Example 24	Example 25
						Hydrogen peroxide/kg	6	7	8	9	10

Example 26

The difference between this example and example 23 is that the formulation of the coating solution further includes 8kg of silane coupling agent, and the silane coupling agent is methyltriethoxysilane.

As shown in Table 7, examples 26 to 30 were different in the amount of methyltriethoxysilane used.

TABLE 7

Example 31

This example is different from example 28 in that vinyltriethoxysilane was used as the silane coupling agent.

Comparative example

Comparative example 1

A Teflon coated metal mesh comprises a metal mesh substrate and a Teflon coating, wherein the Teflon coating is formed by heating and curing a coating liquid on the surface of the metal mesh substrate, and the preparation method of the Teflon coated metal mesh comprises the following steps: (1) deoiling and derusting the surface of the metal net, and then carrying out sand blasting treatment on the surface of the metal net;

(2) uniformly mixing 50kg of teflon powder, 130kg of deionized water, 10kg of emulsifier and 30kg of binder to obtain a coating liquid, wherein the binder is polyvinyl alcohol;

(3) and (3) coating the surface of the metal mesh subjected to sand blasting with a coating solution, then carrying out heat treatment on the metal mesh substrate at 370 ℃, wherein the heat treatment time is 2.5h, and obtaining the Teflon coated metal mesh after the heat treatment is finished.

Comparative example 2

This comparative example differs from example 3 in that the metal mesh substrate was not subjected to the alkali solution immersion treatment.

Performance detection test method

An air jet sand mold testing machine is used for carrying out erosion test on the Teflon coated metal net at room temperature, a metal net with the mesh size of 300 meshes is selected as a tested sample, a flat-laid square sample is 25cm multiplied by 25cm, an AJ-1000 air jet sand blast erosion testing machine produced by Beijing Zhongjing Seiki science and technology Limited is selected as testing equipment, the testing equipment is corrected according to the standard of ASTM-G76-83 air jet erosion testing machine before testing, and erosion particles are alumina particles (240 meshes) provided by Henan Jade abrasion New Material Limited. In the test, the attack angle of the erosion particles was set to 90 °, the erosion speed was set to 14m/s, the erosion was stopped after the sample was eroded until the surface was peeled off, and the time taken for the sample surface to be peeled off (hereinafter referred to as peeling time) was recorded, and the test results are shown in table 8.

TABLE 8

Sample(s)	Peeling time/min	Sample(s)	Peeling time/min
				Example 1	195	Example 18	251
Example 2	198	Example 19	248
				Example 3	204	Example 20	244
Example 4	201	Example 21	258
				Example 5	197	Example 22	261
Example 6	217	Example 23	264
				Example 7	220	Example 24	262
Example 8	225	Example 25	259
				Example 9	221	Example 26	274
Example 10	218	Example 27	278
				Example 11	231	Example 28	282
Example 12	234	Example 29	279
				Example 13	238	Example 30	275
Example 14	235	Example 31	289
				Example 15	232	Comparative example 1	62
Example 16	245	Comparative example 2	84
				Example 17	247	/	/

It can be seen from the combination of examples 1-5 and comparative example 1 and table 8 that the peeling time measured in examples 1-5 is longer than that in comparative example 1, which shows that when the coating solution prepared by using the formulation system of the present application is used with the metal mesh treated by alkali solution, the bonding degree between the metal mesh substrate and the teflon coating layer is higher, and the prepared teflon coated metal mesh has longer service life.

It can be seen from the combination of example 3 and comparative example 2 and table 8 that the peeling time measured in example 3 is longer than that measured in comparative example 2, which shows that the metal mesh substrate soaked by the alkali solution in example 3 has a synergistic effect with the coating solution, which is helpful for improving the bonding degree between the metal mesh substrate and the teflon coating and prolonging the service life of the teflon coated metal mesh.

Combining examples 3, 6-10 and table 8, it can be seen that the peel times measured for examples 6-10 were all longer than example 3, indicating that the addition of the charring aid helps to increase the bond between the metal mesh substrate and the teflon coating and to extend the life of the metal mesh.

Combining examples 8, 11-15 and table 8, it can be seen that examples 11-15 all measured longer peel times than example 8, indicating that the use of phosphorus oxychloride in the preparation of the charring aid helps to increase the bond between the metal mesh substrate and the teflon coating and to extend the life of the metal mesh.

Combining example 13, examples 16-20 and table 8, it can be seen that the peel times measured for examples 16-20 are all longer than for example 13, indicating that ferrous chloride helps to improve the bond between the metal mesh substrate and the teflon coating and to extend the life of the metal mesh.

Combining example 18, examples 21-25 and table 8, it can be seen that examples 21-25 all measured longer peel times than example 18, indicating that hydrogen peroxide helps to improve the bond between the metal mesh substrate and the teflon coating and to extend the life of the metal mesh.

Combining example 23, examples 26-30 and table 8, it can be seen that the peel times measured for examples 26-30 were all longer than example 23, indicating that the silane coupling agent helps to improve the bond between the metal mesh substrate and the teflon coating and to extend the life of the metal mesh.

Combining example 28 and example 31 with table 8, it can be seen that the peel time measured in example 31 is longer than that in example 28, indicating that the silane coupling agent with double bonds in the molecule helps to improve the bonding degree between the metal mesh substrate and the teflon coating, and to prolong the service life of the metal mesh.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.