CN111909591B - Anti-corrosion heat-preservation heat-insulation coating and preparation method thereof - Google Patents

Abstract

The invention discloses a novel anticorrosion heat-insulation coating and a preparation method thereof, wherein the novel anticorrosion heat-insulation coating is formed by mixing A, B two components, wherein the component A comprises mixed resin, a toughening agent, a reactive diluent, a reactive flame retardant, a functional filler and a coupling agent, and the component B comprises: curing agent, curing accelerator, functional filler and coupling agent; the preparation method comprises preparing component A, preparing component B, and mixing the two. The coating has strong adhesive force with a metal matrix, excellent corrosion resistance and low thermal conductivity, has good corrosion resistance, heat insulation and heat insulation properties, is simple and convenient to construct, can be directly coated by blade coating or coated on the surfaces of pipelines and equipment by means of a mould, and effectively solves the corrosion problem under the heat insulation layer.

Description

Anti-corrosion heat-preservation heat-insulation coating and preparation method thereof

Technical Field

The invention belongs to the field of coatings, and particularly relates to an anticorrosive heat-insulating coating and a preparation method thereof.

Background

The heat-insulating layer material is wrapped on the outer surface of the pipeline or the equipment, so that heat loss can be reduced (or cold insulation is performed to prevent the pipeline/the equipment from condensation), the temperature of an operating system is maintained, energy is saved, meanwhile, external harmful media can be prevented from contacting the metal surface of the pipeline or the equipment, the running capacity of the pipeline or the equipment is improved, and the problem that corrosion under the heat-insulating layer frequently occurs on the surface of the pipeline or the equipment which is not provided with an anticorrosive coating or is in a corrosive industrial atmosphere is troublesome.

Under Insulation Corrosion (CUI) refers to a Corrosion phenomenon occurring on the outer surface of a pipe or equipment externally wrapped with Insulation material due to the ingress of condensed water and corrosive substances Under the conditions of system operation, maintenance, failure, etc. The corrosion rate is influenced by factors such as the concentration of a corrosion medium, the oxygen content in the environment, the temperature, the humidity and the like.

However, the exterior of the heat insulating material is still provided with primary stainless steel, aluminum foil or other protective materials, so that CUI is not easy to find, and the structure and the thickness of the heat insulating material make the CUI difficult to detect.

In the petrochemical industry only, pipeline faults caused by CUI account for over 60 percent. Every year, the loss caused by serious problems of dangerous product leakage, abnormal parking of equipment and even casualties caused by equipment and pipeline failures caused by CUI is up to billions of dollars. Similar problems occur in the metallurgical, electrical and other industries.

Most of the existing solutions for solving the problems still remain to improve the corrosion resistance of the metal pipeline coating under the heat-insulating layer, but still have the problems of inconvenient inspection, untimely inspection, difficult replacement and the like.

Therefore, there is a need for a new coating that is not only corrosion resistant but also thermal insulating.

Disclosure of Invention

The purpose of the invention is as follows: the first purpose of the invention is to provide a coating with excellent corrosion resistance, strong adhesion with a metal matrix and good heat insulation performance.

The second purpose of the invention is to provide a preparation method of the coating.

The technical scheme is as follows: the anticorrosive heat-insulating coating is formed by mixing A, B two components;

wherein, the component A comprises the following components in parts by weight: 15-32 parts of mixed resin, 8-18 parts of toughening agent, 5-18 parts of reactive diluent, 0-16 parts of reactive flame retardant, 40-60 parts of functional filler and 1-5 parts of coupling agent;

the component B comprises the following components in parts by weight: 18-36 parts of curing agent, 5-15 parts of curing accelerator, 38-56 parts of functional filler and 1-9 parts of coupling agent.

The coating is prepared by compounding two components with different effects, and has excellent corrosion resistance, strong adhesive force with a metal matrix and good heat insulation performance. Furthermore, the mixed resin in the component A of the coating is formed by premixing bisphenol F type epoxy resin and/or modified novolac epoxy resin with polyfunctional epoxy resin at 120-180 ℃ in nitrogen, and the content of the polyfunctional resin in the mixed resin is not less than 55%. The bisphenol F type epoxy resin is prepared by reacting phenol with formaldehyde under acid catalysis to generate bisphenol F, and then carrying out polycondensation reaction with epoxy chloropropane in the presence of sodium hydroxide, compared with modified novolac epoxy, the bisphenol F type epoxy resin has good fluidity, the heat resistance and the medium resistance of a product obtained by blending the bisphenol F type epoxy resin with the modified novolac epoxy are not affected, and the heat resistance and the corrosion resistance of the product are affected by the participation of the bisphenol F type epoxy resin in the aspects of well adjusting the construction operability of a formula and improving the wettability. The functionality of the modified novolac epoxy is more than 2, the modified novolac epoxy can reach about 3.5 under the influence of modification, the cured novolac epoxy has high strength, good heat resistance and excellent corrosion resistance, but has high brittleness, and the added bisphenol F type epoxy resin can improve the brittleness and enhance the toughness on the basis of not influencing the overall thermal property, mechanical property and chemical property. The polyfunctional resin has high functionality and high reactivity, determines the advantages of large curing crosslinking degree, excellent heat resistance, excellent corrosion resistance, low curing shrinkage and the like of the product, but also has the defects of high viscosity, poor low-temperature wettability and the like, so that the polyfunctional resin can be blended with bisphenol F and/or novolac epoxy at higher temperature, not only can the low-temperature wettability and the construction operability be improved, but also the loss of the heat resistance, the corrosion resistance and the like is small. On the basis, the problem of epoxy group loss at high temperature is considered, and nitrogen protection on the blending system is an ideal and simple operation method. Preferably, the multifunctional epoxy resin is one or two of tetraphenyl glycidyl ether ethane, triphenyl glycidyl ether methane, tetraglycidyl diaminodiphenylmethane, tetraglycidyl xylene diamine and triglycidyl trisisocyanate.

The toughening agent at least comprises one of hydroxyl-terminated liquid nitrile rubber, carboxyl-terminated liquid nitrile rubber, epoxy-terminated liquid nitrile rubber or amino-terminated liquid nitrile rubber.

The reactive flame retardant is brominated epoxy resin, can participate in curing crosslinking reaction, and does not influence the thermal conductivity of a system while ensuring the flame retardant performance.

The functional filler comprises the following raw material components in parts by weight: 2-8 parts of aerogel powder, 0-18 parts of aluminum silicate fiber, 18-26 parts of sepiolite powder, 0-14 parts of potassium titanate whisker, 5-12 parts of ferrophosphorus powder, 8-20 parts of hollow ceramic microsphere and 12-30 parts of hollow glass microsphere, wherein the aluminum silicate fiber and the potassium titanate whisker are not 0 at the same time.

Still further, the curing agent in the component B of the coating is maleic anhydride modified polyamide curing agent and/or maleic anhydride modified aromatic amine curing agent. The reason for adopting the curing agent is that the mixed resin contains active groups such as ether bond, hydroxyl, epoxy group and the like; the aromatic amine cured product has excellent heat resistance and medium resistance, the polyamide has good toughness and peel strength, and after the polyamide is modified by maleic anhydride, the curing rate is improved, and the toxicity is reduced; the maleic anhydride modified aromatic amine curing agent/maleic anhydride modified polyamide curing agent and the mixed resin are cured and crosslinked to form a three-dimensional network structure, and the temperature resistance and the corrosion resistance of the whole product are reflected to the greatest extent.

The curing accelerator may include at least one of (2, 4, 6-tris (dimethylaminomethyl) phenol, 2-ethyl-4-methylimidazole, benzyldimethylamine or boron trifluoride amine complex.

The functional filler comprises the following raw material components in parts by weight: 2-8 parts of aerogel powder, 0-15 parts of aluminum silicate fiber, 15-22 parts of sepiolite powder, 0-18 parts of potassium titanate whisker, 8-15 parts of ferrophosphorus powder, 8-16 parts of hollow ceramic microsphere and 18-32 parts of hollow glass microsphere, wherein the aluminum silicate fiber and the potassium titanate whisker are not 0 at the same time.

The method for preparing the anticorrosive heat-insulating coating comprises the following steps:

(1) preparing a component A:

1) stirring the mixed resin, the toughening agent and the reactive diluent for 1-2 hours at room temperature of 180 ℃, a dispersion rotating speed of 1500-3000 rpm and a stirring rotating speed of 20-60 rpm, and adopting nitrogen for protection when the temperature is higher than 120 ℃;

2) adding a reactive flame retardant into the mixed solution obtained in the step 1), continuously stirring for 40-60 min, and keeping the reaction temperature, the rotation speed and the atmosphere;

3) adding a coupling agent into the mixed solution obtained in the step 2), continuously stirring for 20-40 min, and keeping the reaction temperature, the rotation speed and the atmosphere;

4) adding a functional filler into the mixed solution obtained in the step 3), continuing for 1-2 hours, and keeping the reaction temperature, the rotation speed and the atmosphere;

5) cleaning the wall of the reaction kettle and the blades, and then continuously stirring uniformly;

6) stopping heating, vacuumizing and removing bubbles to obtain a component A;

(2) preparing a component B:

1) stirring a curing agent, a curing accelerator and a coupling agent for 1-2 hours at normal temperature at a dispersion rotating speed of 1200-2000 rpm and a stirring rotating speed of 20-60 rpm;

2) adding a functional filler into the mixed solution obtained in the step 1), continuously stirring for 1-2 hours, and keeping the reaction temperature and the rotation speed;

3) cleaning the wall of the reaction kettle and the blades, and then continuously stirring uniformly;

4) vacuumizing and removing bubbles to obtain a component B;

(3) preparing a coating: and mixing the component A and the component B to obtain the coating.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: the coating has excellent corrosion resistance, strong adhesive force with a metal matrix, good heat preservation and heat insulation performance due to low heat conductivity, simple and convenient construction, and can be directly coated by blade coating or coated on the surfaces of pipelines and equipment by means of a mould, thereby effectively solving the corrosion problem under the heat preservation layer.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to examples.

It should be noted that the reactive diluent used in the component a of the coating of the present invention may include at least one of glycol diglycidyl ether, C12-14 aliphatic glycidyl ether, 1, 4-butanediol diglycidyl ether, polypropylene glycol diglycidyl ether, propylene oxide benzyl ether, benzyl glycidyl ether, butyl glycidyl ether, and 1, 6-hexanediol diglycidyl ether, and the reactive diluent has a reactive functional group, and participates in the reaction of the system during curing, so as to reduce the viscosity to the maximum extent, ensure good workability, and not reduce the heat resistance and corrosion resistance of the system; one or more proper reactive diluents are selected for compatibility, so that the tensile shear strength of the coating can be improved, and the toughness can be enhanced.

The coupling agent is silane coupling agent, and can be at least one of 3-aminopropyl trimethoxy silane, gamma-aminopropyl triethoxy silane, aniline methyl triethoxy silane, 4-anilino triethoxy silane, N- (2-aminoethyl) -3-aminopropyl trimethoxy silane, 2, 3-glycidoxypropyl methyl dimethoxy silane, vinyl trimethoxy silane and vinyl tri (beta-methoxyethoxy) silane, wherein the coupling agent in the component B can not carry epoxy group. Preferably, the silane coupling agent may be gamma-aminopropyltriethoxysilane.

In addition, the base materials used in the present invention are commercially available.

Example 1

The coating of this example was prepared by blending A, B in a 4:1 weight ratio. The specific raw materials of the component A and the component B are shown as follows.

TABLE 1A Components starting materials

TABLE 2B Components starting materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	20	5	43	4

Wherein in the component A, the mixed resin is prepared by premixing 40 parts of modified novolac epoxy resin and 60 parts of tetraglycidyl diaminodiphenylmethane at 160 ℃ in nitrogen. The toughening agent is epoxy-terminated liquid nitrile rubber. The reactive diluent is 30 parts of 1, 4-butanediol diglycidyl ether and 70 parts of propylene oxide benzyl ether. The reactive flame retardant is brominated bisphenol A epoxy resin. The functional filler comprises the following components in parts by weight: 4 parts of silica aerogel powder, 12 parts of 3mm aluminum silicate fiber, 18 parts of sepiolite powder, 8 parts of 1.5mm potassium titanate whisker, 6 parts of ferrophosphorus powder, 11 parts of hollow ceramic microspheres and 26 parts of hollow glass microspheres. The coupling agent is 2, 3-glycidoxypropylmethyldimethoxysilane.

In the component B, the curing agent is maleic anhydride modified aromatic amine curing agent. The curing accelerator is 2-ethyl-4-methylimidazole. The functional filler comprises the following raw material components in parts by weight: 4 parts of silica aerogel powder, 8 parts of 3mm aluminum silicate fiber, 17 parts of sepiolite powder, 12 parts of 1.5mm potassium titanate whisker, 12 parts of ferrophosphorus powder, 14 parts of hollow ceramic microspheres and 25 parts of hollow glass microspheres. The coupling agent is gamma-aminopropyl triethoxysilane.

The coating preparation method of this embodiment includes the steps of:

(1) preparing a component A:

1) placing the mixed resin, the toughening agent and the reactive diluent in a closed reaction kettle with dispersing and stirring functions, and stirring for 1h under the conditions of 140 ℃ nitrogen protection, 1800rpm dispersion rotating speed and 36rpm stirring rotating speed;

2) adding a reactive flame retardant into the mixed solution obtained in the step 1), continuously stirring for 40min, and keeping the reaction temperature, the rotation speed and the atmosphere;

3) adding a coupling agent into the mixed solution obtained in the step 2), continuously stirring for 20min, and keeping the reaction temperature, the rotation speed and the atmosphere;

4) cleaning the toothed kettle, cleaning the materials which are not uniformly stirred on the inner wall of the reaction kettle or the stirring paddle into the kettle, continuously stirring for 40min, and keeping the reaction temperature, the rotation speed and the atmosphere;

5) adding aerogel powder into the mixed solution obtained in the step 4), continuously stirring for 60min, and keeping the reaction temperature, the rotation speed and the atmosphere;

6) adding sepiolite powder and ferrophosphorus powder into the mixed solution obtained in the step 5), continuously stirring for 30min, and keeping the reaction temperature, the rotation speed and the atmosphere;

7) turning off the high-speed dispersion, adding hollow ceramic microspheres and hollow glass microspheres into the mixed solution obtained in the step 6), continuously stirring for 30min, and keeping the reaction temperature, the rotation speed and the atmosphere;

8) keeping high-speed dispersion closed, adding aluminum silicate fibers and potassium titanate whiskers into the mixed solution in the step 7), reducing the stirring speed to 25rpm, continuing stirring for 30min, and keeping the reaction temperature, the rotation speed and the atmosphere;

9) cleaning the wall of the reaction kettle and the blades, and then continuously stirring for 20 min;

10) stopping heating (removing nitrogen gas) and vacuumizing to remove bubbles for 30min, and taking out of the kettle.

(2) Preparing a component B:

1) putting a curing agent, a curing accelerator and a coupling agent into a closed reaction kettle with dispersing and stirring functions, and stirring for 1h at the conditions of 1200rpm dispersing rotating speed and 30rpm stirring rotating speed at normal temperature;

2) adding aerogel powder into the mixed solution obtained in the step 1), continuously stirring for 60min, and keeping the reaction temperature and the rotation speed (if the temperature of the solution in the kettle is higher than 45 ℃, external circulation cooling is required);

3) adding sepiolite powder and ferrophosphorus powder into the mixed solution obtained in the step 2), continuously stirring for 30min, and keeping the reaction temperature and the rotation speed;

4) turning off the high-speed dispersion, adding hollow ceramic microspheres and hollow glass microspheres into the mixed solution obtained in the step 3), continuously stirring for 30min, and keeping the reaction temperature and the rotation speed;

5) keeping high-speed dispersion closed, adding aluminum silicate fibers and potassium titanate whiskers into the mixed solution obtained in the step 4), reducing the stirring speed to 20rpm, continuing stirring for 30min, and keeping the reaction temperature and the rotation speed;

6) cleaning the wall of the reaction kettle and the blades, and then continuously stirring for 15 min;

7) keeping the temperature, vacuumizing to remove bubbles for 30min, and taking out of the kettle;

(3) preparing a coating: and uniformly mixing the component A and the component B according to the weight part of 4: 1.

Example 2

The coating of this example is made by mixing A, B components in a weight ratio of 15: 1. The specific raw materials of the component A and the component B are shown as follows.

TABLE 3A Components starting materials

Raw materials	Mixed resin	Toughening agent	Reactive diluent	Functional filler	Coupling agent
						Content/portion	32	12	12	50	5

TABLE 4B Components starting materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	18	8	50	7

The resin was mixed as in example 1.

The toughening agent was the same as in example 1.

The reactive diluent was the same as in example 1.

The functional filler of component A is the same as that of example 1.

The curing agent was the same as in example 1.

The curing was performed as in example 1.

The functional filler of component B is the same as that of example 1.

Coupling agent as in example 1

The coating was prepared as described in example 1, except that the reaction temperature was controlled <50 ℃ for the preparation of the a-component.

Example 3

The coating of this example was prepared by blending A, B in a 20:1 ratio by weight. The specific raw materials of the component A and the component B are shown as follows.

TABLE 5A Components starting materials

Raw materials	Mixed resin	Toughening agent	Reactive diluent	Reactive flame retardant	Functional filler	Coupling of
							Content/portion	15	18	5	16	40	1

TABLE 6B Components starting materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	36	15	38	1

Wherein the mixed resin is formed by premixing 20 parts of bisphenol F type epoxy resin, 20 parts of modified novolac epoxy resin and 60 parts of tetraglycidyl diaminodiphenylmethane at 160 ℃ in nitrogen.

The toughening agent was the same as in example 1.

Reactive diluent propylene oxide benzyl ether.

The reaction type flame retardant was the same as in example 1.

The functional filler of the component A comprises the following raw material components in parts by weight: 2 parts of carbon-doped silicon aerogel powder, 26 parts of sepiolite powder, 14 parts of 3mm potassium titanate whisker, 5 parts of ferrophosphorus powder, 8 parts of hollow ceramic microspheres and 30 parts of hollow glass microspheres.

The curing agent is maleic anhydride modified polyamide curing agent.

The curing accelerator is boron trifluoride amine complex.

The functional filler of the component B comprises the following raw material components in parts by weight: 8 parts of carbon-doped silicon aerogel powder, 22 parts of sepiolite powder, 18 parts of 3mm potassium titanate whisker, 8 parts of ferrophosphorus powder, 16 parts of hollow ceramic microspheres and 18 parts of hollow glass microspheres.

The coupling agent N- (2-aminoethyl) -3-aminopropyltrimethoxysilane.

The coating was prepared as described in example 1, except that the dispersion speed was 3000rpm, the stirring speed was 60rpm, and then the stirring speed was reduced to 30 rpm; the dispersion speed of the component B is 2000rpm, the stirring speed is 60rpm, and then the stirring speed is reduced to 30 rpm.

Example 4

The coating of this example is made by mixing A, B components in a weight ratio of 1: 1. The specific raw materials of the component A and the component B are shown as follows.

TABLE 7A Components starting materials

Raw materials	Mixed resin	Toughening agent	Reactive diluent	Reactive flame retardant	Functional filler	Coupling agent
							Content/portion	15	10	9	8	60	5

TABLE 8B Components starting materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	22	10	56	9

The resin was mixed as in example 1.

The toughening agent is carboxyl-terminated liquid nitrile rubber.

Reactive diluent C12-14 fatty glycidyl ether.

The reactive flame retardant is dibromo-pentaerythritol epoxy resin.

The functional filler of the component A comprises the following raw material components in parts by weight: 8 parts of aerogel powder, 18 parts of 1mm aluminum silicate fiber, 20 parts of sepiolite powder, 12 parts of ferrophosphorus powder, 20 parts of hollow ceramic microspheres and 12 parts of hollow glass microspheres.

The curing agent comprises 20 parts of maleic anhydride modified polyamide curing agent and 80 parts of maleic anhydride modified aromatic amine curing agent.

The curing accelerator was the same as in example 3.

The functional filler of the component B comprises the following raw material components in parts by weight: 2 parts of titanium dioxide doped aerogel powder, 15 parts of 1mm aluminum silicate fiber, 15 parts of sepiolite powder, 15 parts of ferrophosphorus powder, 8 parts of hollow ceramic microspheres and 35 parts of hollow glass microspheres.

The coupling agent in the component A is silane coupling agent 2, 3-glycidoxypropyl methyldimethoxysilane, and the silane coupling agent aniline methyltriethoxysilane in the component B.

The coating was prepared as described in example 1.

Example 5

The coating of this example is made by mixing A, B components in a weight ratio of 10: 1. The specific raw materials of the component A and the component B are shown as follows.

TABLE 9A Components starting materials

Raw materials	Mixed resin	Toughening agent	Reactive diluent	Reactive flame retardant	Functional filler	Coupling of
							Content/portion	22	16	18	12	48	2

TABLE 10B Components materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	30	11	52	5

The resin was mixed as in example 3.

The toughening agent was the same as in example 1.

The reactive diluent was the same as in example 1.

The reaction type flame retardant was the same as in example 4.

The functional filler of component A is the same as that of example 1.

The curing agent was the same as in example 4.

The curing accelerator was the same as in example 4.

The functional filler of component B is the same as that of example 1.

The coupling agent was the same as in example 1.

The coating was prepared as described in example 1.

Example 6

The coating of this example is made by mixing A, B components in a weight ratio of 5: 1. The specific raw materials of the component A and the component B are shown as follows.

TABLE 11A Components starting materials

Raw materials	Mixed resin	Toughening agent	Reactive diluent	Reactive flame retardant	Functional filler	Coupling of
							Content/portion	26	8	6	4	52	3

TABLE 12B Components materials

Raw materials	Curing agent	Curing accelerator	Functional filler	Coupling agent
					Content/portion	20	5	43	4

Wherein the mixed resin is prepared by premixing 20 parts of bisphenol F type epoxy resin, 15 parts of modified novolac epoxy resin, 30 parts of tetraglycidyl diaminodiphenylmethane and 35 parts of triglycidyl triple isocyanate in nitrogen at 180 DEG C

The toughening agent comprises 30 parts of hydroxyl-terminated liquid nitrile rubber and 70 parts of epoxy-terminated liquid nitrile rubber.

Reactive diluent 1, 4-butanediol diglycidyl ether.

The reaction type flame retardant was the same as in example 1.

The functional filler of component A is the same as that of example 1.

The curing agent was the same as in example 1.

The curing accelerator was 50 parts of benzyldimethylamine and 50 parts of 2-ethyl-4-methylimidazole.

The functional filler of component B is the same as that of example 1.

The coupling agent was the same as in example 1.

The coating preparation method is as described in example 1, and is different in that the dispersion speed is 1500rpm, the stirring speed is 20rpm, and then the stirring speed is reduced to 10 rpm; the dispersion speed of the component B is 1200rpm, the stirring speed is 20rpm, and then the stirring speed is reduced to 10 rpm.

Comparative example 1

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the mixed resin in the component A comprises 50 parts of tetraglycidyl xylene diamine and 50 parts of triglycidyl triple isocyanate.

Comparative example 2

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the coating toughening agent is nitrile rubber-26.

Comparative example 3

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the diluent is butyl acetate.

Comparative example 4

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the flame retardant is FR-701 which is purchased from Hongtai flame retardant materials Co., Ltd, Dongguan.

The preparation method of the coating comprises the specific steps as described in example 1.

Comparative example 5

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the component A is not protected by nitrogen when reacting.

Comparative example 6

The composition and preparation method of the coating raw material of the comparative example are basically the same as those of example 1, except that: the step of removing bubbles by vacuum is left.

Performance testing

After the component A and the component B of the coatings described in the embodiments 1-6 and the comparative examples 1-6 are uniformly mixed according to the proportion, samples are prepared according to the test requirements and the performance is detected.

Corrosion resistance: GB/T9274-1988 (5% sulfuric acid, continuous immersion for 72 h; 5% sodium hydroxide, continuous immersion for 72h), actual test: 5% sulfuric acid, soaking for 240h continuously, and observing the surface of the coating. 5 percent of sodium hydroxide, soaking for 240 hours continuously, and observing the surface of the coating.

Equivalent thermal conductivity [ < 0.05W/(m.K) ]: HG/T5182-2017

The adhesive force after temperature change resistant circulation (the pull-open method is more than or equal to 2.5 MPa): HG/T5178-2017

Resistance to salt fog after temperature change cycling (standard 1440h, pass): HG/T5178-2017

The experimental results obtained are shown in table 7 below.

TABLE 13 comparison of Performance between examples 1 to 6 and comparative examples 1 to 6

Through the comparison of the test performances of the above examples and comparative examples, it can be found that: the liquid nitrile rubber has bisphenol F resin and/or novolac epoxy resin and a resin matrix with multiple functional groups, has good corrosion resistance and excellent performance after temperature change circulation resistance in a maleic anhydride modified aromatic amine/or maleic anhydride modified polyamide system, and has high peel strength after toughening of liquid nitrile rubber with end reaction groups; after functional fillers with low thermal conductivity (aerogel, aluminum silicate fibers, sepiolite powder, ferrophosphorus powder, hollow ceramic microspheres, hollow glass microspheres and the like) are added, the overall material has low thermal conductivity and is an anticorrosive heat-insulating coating used in a composite field.

When selecting materials and adjusting the process, the problems of adding materials with high thermal conductivity, remaining inert liquid molecules, loss of active groups, introduction of large-size bubbles and the like are avoided as much as possible.

Based on the limitations and disadvantages of heat-insulating and corrosion-resistant materials in the traditional chemical and metallurgical industries and the disassembly and inspection thereof, the invention provides an anticorrosive heat-insulating coating and a preparation method thereof, the coating can be directly blade-coated or coated on the surfaces of pipelines and equipment by means of a mold, has good heat resistance, corrosion resistance and low heat conductivity, has excellent adhesive force with a metal matrix, has excellent aging resistance, and avoids the possibility that oxygen, moisture and corrosive ions invade into the coating to corrode the metal matrix, and the coating has the advantages of easy obtainment of raw materials in a formula, simple manufacturing process and convenient construction.

Claims (5)

1. An anticorrosive heat preservation thermal barrier coating, its characterized in that: a, B is prepared by mixing the two components;

wherein, the component A comprises the following components in parts by weight: 15-32 parts of mixed resin, 8-18 parts of toughening agent, 5-18 parts of reactive diluent, 0-16 parts of reactive flame retardant, 40-60 parts of functional filler and 1-5 parts of coupling agent; the component A is prepared by premixing bisphenol F type epoxy resin and/or modified novolac epoxy resin with polyfunctional epoxy resin at 120-180 ℃ in nitrogen, wherein the content of the polyfunctional epoxy resin in the mixed resin is not less than 55%, and the polyfunctional epoxy resin is one or two of tetraphenyl glycidyl ether ethane, triphenyl glycidyl ether methane, tetraglycidyl diamino diphenyl methane, tetraglycidyl xylene diamine and triglycidyl isocyanurate; the toughening agent at least comprises one of hydroxyl-terminated liquid nitrile rubber, carboxyl-terminated liquid nitrile rubber, epoxy-terminated liquid nitrile rubber or amino-terminated liquid nitrile rubber; the reactive flame retardant is brominated epoxy resin; the functional filler comprises the following raw material components in parts by weight: 2-8 parts of aerogel powder, 0-18 parts of aluminum silicate fiber, 18-26 parts of sepiolite powder, 0-14 parts of potassium titanate whisker, 5-12 parts of ferrophosphorus powder, 8-20 parts of hollow ceramic microsphere and 12-30 parts of hollow glass microsphere, wherein the aluminum silicate fiber and the potassium titanate whisker are not 0 at the same time;

the component B comprises the following components in parts by weight: 18-36 parts of curing agent, 5-15 parts of curing accelerator, 38-56 parts of functional filler and 1-9 parts of coupling agent.

2. The corrosion-resistant heat-insulating thermal-insulating coating according to claim 1, characterized in that: the curing agent in the component B is maleic anhydride modified polyamide curing agent and/or maleic anhydride modified aromatic amine curing agent.

3. The corrosion-resistant heat-insulating thermal-insulating coating according to claim 1, characterized in that: the curing accelerator includes at least one of (2, 4, 6-tris (dimethylaminomethyl) phenol, 2-ethyl-4-methylimidazole, benzyldimethylamine or boron trifluoride amine complex.

4. The corrosion-resistant heat-insulating thermal-insulating coating according to claim 1, characterized in that: the functional filler in the component B comprises the following raw material components in parts by weight: 2-8 parts of aerogel powder, 0-15 parts of aluminum silicate fiber, 15-22 parts of sepiolite powder, 0-18 parts of potassium titanate whisker, 8-15 parts of ferrophosphorus powder, 8-16 parts of hollow ceramic microsphere and 18-32 parts of hollow glass microsphere, wherein the aluminum silicate fiber and the potassium titanate whisker are not 0 at the same time.

5. A method for preparing the corrosion-resistant heat-insulating thermal-insulating coating of claim 1, which is characterized by comprising the following steps:

(1) preparing a component A:

1) stirring the mixed resin, the toughening agent and the reactive diluent for 1-2 hours at room temperature-180 ℃, 1500-3000 rpm dispersion rotation speed and 20-60 rpm stirring rotation speed, and adopting nitrogen for protection when the temperature is higher than 120 ℃;

2) adding a reactive flame retardant into the mixed solution obtained in the step 1), continuously stirring for 40-60 min, and keeping the reaction temperature, the rotation speed and the atmosphere;

3) adding a coupling agent into the mixed solution obtained in the step 2), continuously stirring for 20-40 min, and keeping the reaction temperature, the rotation speed and the atmosphere;

4) adding a functional filler into the mixed solution obtained in the step 3), continuing for 1-2 hours, and keeping the reaction temperature, the rotation speed and the atmosphere;

5) cleaning the wall of the reaction kettle and the blades, and then continuously stirring uniformly;

6) stopping heating, vacuumizing and removing bubbles to obtain a component A;

(2) preparing a component B:

1) stirring a curing agent, a curing accelerator and a coupling agent for 1-2 hours at normal temperature at a dispersion rotating speed of 1200-2000 rpm and a stirring rotating speed of 20-60 rpm;

2) adding a functional filler into the mixed solution obtained in the step 1), continuously stirring for 1-2 hours, and keeping the reaction temperature and the rotation speed;

3) cleaning the wall of the reaction kettle and the blades, and then continuously stirring uniformly;

4) vacuumizing and removing bubbles to obtain a component B;

(3) preparing a coating: and mixing the component A and the component B to obtain the coating.