CN116554759A

CN116554759A - A kind of coating composition and its preparation method and application

Info

Publication number: CN116554759A
Application number: CN202310718284.7A
Authority: CN
Inventors: 陈强; 贺玉平; 范艺千; 谭祖中; 袁尧
Original assignee: CRRC Zhuzhou Vehicle Co Ltd
Current assignee: CRRC Zhuzhou Vehicle Co Ltd
Priority date: 2023-06-16
Filing date: 2023-06-16
Publication date: 2023-08-08
Also published as: WO2024254995A1

Abstract

The application relates to a coating composition and its preparation method and application, belonging to the technical field of coating anticorrosion; the coating composition includes A component and B component, wherein, the components of A component include polymagnesium aluminum silicate, amine Blending agent, defoamer, dispersant, barium sulfate, zinc phosphate, epoxy emulsion, liquid epoxy resin and thickener; the components of component B include: modified amine water-based epoxy curing agent and anti-flash rust agent; By adding epoxy emulsion and liquid epoxy resin to the composition, the solid content, cross-linking density, chemical resistance and corrosion resistance of the applied paint film are enhanced, and the dry film thickness of single-pass spraying can reach more than 150 μm; Under the condition of dry film thickness of 70μm, the performance index of salt spray resistance can reach 1000h, and under the condition of dry film thickness of 150μm, the performance index of salt spray resistance can reach more than 1600h.

Description

Coating composition and preparation method and application thereof

Technical Field

The application relates to the technical field of paint corrosion prevention, in particular to a paint composition and a preparation method and application thereof.

Background

At present, the water-based epoxy paint for the domestic rail transit vehicle generally has the problems of small thickness of one-time film formation and low corrosion resistance of a single-pass coating (generally, the salt spray resistance index is 500h under the condition of 70 mu m of dry film thickness), the required thickness and corrosion resistance can be achieved only by spraying for a plurality of times, the defects of complex construction process and long construction period exist, and meanwhile, the interlayer adhesive force and the corrosion resistance of the coating are reduced easily due to residual water of a paint film under the condition that the primer is sprayed for one time, namely, the primer is sprayed for a plurality of times.

Disclosure of Invention

The application provides a coating composition, a preparation method and application thereof, so as to solve the problem of small thickness of a one-time film of the existing coating.

In a first aspect, the present application provides a coating composition comprising an a-component and a B-component, wherein the ingredients of the a-component comprise a magnesium aluminum polysilicate, an amine neutralizer, an antifoaming agent, a dispersant, barium sulfate, zinc phosphate, an epoxy emulsion, a liquid epoxy resin, and a thickener; the component B comprises the following components: modified amine aqueous epoxy curing agent and anti-flash rust agent.

As an alternative embodiment, the component A comprises, by mass, 0.1-0.8 part of poly-magnesium aluminum silicate, 0.3-0.8 part of amine neutralizer, 0.2-0.5 part of defoamer, 0.5-2 parts of dispersant, 15-30 parts of barium sulfate, 6-12 parts of zinc phosphate, 10-30 parts of epoxy emulsion, 20-40 parts of liquid epoxy resin and 0.2-0.5 part of thickener; and/or

The component B comprises the following components in parts by mass: 75-85 parts of modified amine waterborne epoxy curing agent and 8-16 parts of flash rust inhibitor.

As an alternative embodiment, the ingredients of the a component further comprise 6.5-15 parts of a first solvent; and/or

The component B also comprises 8-16 parts of a second solvent.

As an alternative embodiment, the mass ratio of the a component and the B component is (7-9): 1.

as an alternative embodiment, the epoxy value of the epoxy emulsion is less than or equal to 0.25.

As an alternative embodiment, the liquid epoxy resin comprises a liquid bisphenol a epoxy resin; and/or

The liquid bisphenol A type epoxy resin comprises at least one of E55, E51 and E44.

As an alternative embodiment, the defoamer includes at least one of polydimethylsiloxane and tributyl phosphate; and/or

The dispersing agent comprises fatty acid polyethylene glycol; and/or

The thickener comprises a hydrophobic group modified ethoxypolyurethane polymer.

In a second aspect, the present application provides a method of preparing a coating composition, the method comprising:

mixing and grinding a first solvent, poly-magnesium aluminum silicate, a dispersing agent, barium sulfate, zinc phosphate and part of defoaming agent to obtain a primary mixed material;

mixing the primary mixed material, the epoxy emulsion and the liquid epoxy resin, and then mixing the primary mixed material, the epoxy emulsion and the liquid epoxy resin with a thickening agent and a residual defoaming agent to obtain a component A;

mixing a modified amine aqueous epoxy curing agent, a second solvent and a flash rust inhibitor to obtain a component B;

according to the A component and the B component, a coating composition is obtained.

As an alternative embodiment, the fineness of the primary mixed material is less than or equal to 40 mu m; and/or

The viscosity of the component A is 2-4 Pa.s.

In a third aspect, the present application provides a component comprising a substrate and a coating applied to at least a portion of the surface of the substrate, the components of the coating comprising a component a and a component B, wherein the components of the component a comprise a magnesium aluminum polysilicate, an amine neutralizer, a defoamer, a dispersant, barium sulfate, zinc phosphate, an epoxy emulsion, a liquid epoxy resin, and a thickener; the component B comprises the following components: modified amine aqueous epoxy curing agent and anti-flash rust agent.

Compared with the prior art, the technical scheme provided by the embodiment of the application has the following advantages:

according to the coating composition provided by the embodiment of the application, the solid content, the crosslinking density, the chemical resistance and the corrosion resistance of a paint film applied by the coating composition are enhanced by adding the epoxy emulsion and the liquid epoxy resin into the components, and the thickness of a dry film in single-pass spraying construction can reach more than 150 mu m; under the condition of the dry film thickness of 70 mu m, the salt spray resistance index can reach 1000h, and under the condition of the dry film thickness of 150 mu m, the salt spray resistance index can reach more than 1600 h.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.

Fig. 1 is a flowchart of a method provided in an embodiment of the present application.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present application based on the embodiments herein.

Unless specifically indicated otherwise, the various raw materials, reagents, instruments, equipment, and the like used in this application are commercially available or may be prepared by existing methods.

The embodiment of the application provides a coating composition, which comprises an A component and a B component, wherein the components of the A component comprise poly magnesium aluminum silicate, an amine neutralizer, a defoamer, a dispersant, barium sulfate, zinc phosphate, an epoxy emulsion, a liquid epoxy resin and a thickener; the component B comprises the following components: modified amine aqueous epoxy curing agent and anti-flash rust agent.

Further, the component A comprises, by mass, 0.1-0.8 part of poly magnesium aluminum silicate, 0.3-0.8 part of amine neutralizer, 0.2-0.5 part of defoamer, 0.5-2 parts of dispersant, 15-30 parts of barium sulfate, 6-12 parts of zinc phosphate, 10-30 parts of epoxy emulsion, 20-40 parts of liquid epoxy resin, 0.2-0.5 part of thickener and 6.5-15 parts of first solvent; the component B comprises the following components in parts by mass: 75-85 parts of modified amine waterborne epoxy curing agent, 8-16 parts of flash rust inhibitor and 8-16 parts of second solvent. The first solvent and the second solvent may be specifically selected from deionized water.

The poly-magnesium aluminum silicate has the functions of preventing sinking and sagging, and the mass fraction of the poly-magnesium aluminum silicate is controlled to be 0.1-0.8 part, and the adverse effects of overlarge mass value are that the viscosity of the paint is large, the production and the construction are unfavorable, and the adverse effects of overlarge small mass value are that the paint can sink and the paint is easy to flow down during the construction.

The amine neutralizer has the function of regulating the pH value of the paint, controlling the mass fraction of the amine neutralizer to be 0.3-0.8 part, and influencing the storage stability, the workability and the flash rust prevention of the paint when the pH value of the paint is too large or too small.

The mass fraction of the defoaming agent is controlled to be 0.2-0.5 part, and the adverse effect of the excessive mass value is that the coating film is easy to shrink, and the adverse effect of the excessive mass value is that the defoaming agent cannot perform the defoaming function. In some embodiments, the defoamer may be selected from at least one of polydimethylsiloxane and tributyl phosphate.

The mass fraction of the dispersing agent is controlled to be 0.5-2 parts, and the adverse effect of the excessive mass value is that the water resistance and salt spray resistance of a coating film are affected, and the adverse effect of the excessive mass value is that the coating is easy to get coarse and sink. In some embodiments, the dispersant may be selected from fatty acid polyethylene glycols.

The zinc phosphate has the function of enhancing the corrosion resistance of the coating, the mass fraction of the zinc phosphate is controlled to be 6-12 parts, and the adverse effect of the small mass fraction is that the corrosion resistance of the coating is weakened and the coating is easy to rust.

The epoxy emulsion has the function of a film forming substance, the mass fraction of the epoxy emulsion is controlled to be 10-30 parts, the adverse effect of the excessive mass value is that the gloss of a coating film is high, the interlayer adhesive force is affected, and the adverse effect of the excessive mass value is that the adhesive force and the corrosion resistance of the coating film are affected.

The liquid epoxy resin has the functions of a film forming substance, the mass fraction of the liquid epoxy resin is controlled to be 20-40 parts, the adverse effect of the excessive mass value is that the paint film is slow in dryness, and the adverse effect of the excessive mass value is that the paint film is low in crosslinking density and poor in corrosion resistance. In some embodiments, the liquid epoxy resin comprises a liquid bisphenol a type epoxy resin, further the liquid bisphenol a type epoxy resin comprises at least one of E55, E51, E44.

The mass fraction of the thickener is controlled to be 0.2-0.5 part for adjusting the viscosity of the paint, so that the viscosity of the paint is ensured to be within a certain range. In some embodiments, the thickener may be selected from hydrophobic group modified ethoxypolyurethane polymers.

The mass fraction of the modified amine waterborne epoxy curing agent is controlled to be 75-85 parts, the adverse effect of the excessive mass value is that the corrosion resistance of a paint film is poor, and the adverse effect of the too small mass value is that the reaction of components A and B is incomplete, so that the performance of the paint film is affected. The modified amine waterborne epoxy curing agent may be selected from CTW-6061B waterborne epoxy curing agent or EH 613w/80WA waterborne epoxy curing agent.

The mass fraction of the anti-flash rust agent is controlled to be 8-16 parts, and the adverse effect of the excessive mass value is that the storage stability of the coating is affected, and the adverse effect of the excessive mass value is that the anti-rust performance is not achieved. The flash rust inhibitor may specifically be selected from SC2190Z or SC2195A.

In some embodiments, the mass ratio of the A component to the B component is (7-9): 1. preferably, the mass ratio of the component A to the component B is 8:1.

in some embodiments, the epoxy value of the epoxy emulsion is less than or equal to 0.25, and the reason for controlling the epoxy value of the epoxy emulsion to be less than or equal to 0.25 is to enable the crosslinking density of the paint film to be high, and the adhesive force and the corrosion resistance of the paint film are enhanced.

The coating composition selects epoxy emulsion and liquid epoxy resin, the solid content, the crosslinking density, the chemical resistance and the corrosion resistance of a paint film are enhanced, and when the coating composition is applied as the paint film, the thickness of a single-pass spraying construction dry film of the paint film can reach more than 150 mu m; under the condition of the dry film thickness of 70 mu m, the salt spray resistance index can reach 1000 hours, and under the condition of the dry film thickness of 150 mu m, the salt spray resistance index can reach more than 1600 hours; the interlayer adhesive force between the paint film and the oil/water-based acrylic acid finish paint and between the paint film and the oil/water-based polyurethane finish paint is not less than 5MPa.

As shown in fig. 1, based on one general inventive concept, the present embodiment also provides a method of preparing a coating composition, the method comprising:

s1, mixing and grinding a first solvent, poly-magnesium aluminum silicate, a dispersing agent, barium sulfate, zinc phosphate and part of defoaming agent to obtain a primary mixed material;

in some embodiments, the fineness of the primary mix is less than or equal to 40 μm. Specifically, in the embodiment, deionized water, poly magnesium aluminum silicate, a dispersing agent, a defoaming agent, barium sulfate and zinc phosphate are sequentially added into a dispersing tank according to the metering, and the materials are uniformly dispersed and then ground until the fineness is less than or equal to 40 mu m, so that a primary mixed material is obtained.

S2, mixing the primary mixed material, the epoxy emulsion and the liquid epoxy resin, and then mixing the primary mixed material, the epoxy emulsion and the liquid epoxy resin with a thickening agent and a residual defoaming agent to obtain a component A;

in some embodiments, the viscosity of the a-component is 2 to 4 Pa-s. Specifically, in the embodiment, adding epoxy emulsion into a paint mixing tank according to the measurement, adding liquid epoxy resin and ground primary mixed material while stirring, sequentially adding a defoaming agent and a thickening agent, stirring for 15-30 min, adjusting the viscosity of the filtered material to 2-4 Pa.s, filtering again to remove impurities, and discharging to obtain the component A.

S3, mixing the modified amine waterborne epoxy curing agent, the second solvent and the flash rust inhibitor to obtain a component B;

specifically, in the embodiment, the modified amine aqueous epoxy curing agent, deionized water and the flash rust inhibitor are sequentially put into a dispersing tank according to the metering, and the materials are uniformly dispersed to obtain the component B.

S4, obtaining the coating composition according to the component A and the component B.

The present application is further illustrated below in conjunction with specific examples. It should be understood that these examples are illustrative only of the present application and are not intended to limit the scope of the present application. The experimental procedures, which are not specified in the following examples, are generally determined according to national standards. If the corresponding national standard does not exist, the method is carried out according to the general international standard, the conventional condition or the condition recommended by the manufacturer.

Example 1

A coating is prepared from the following components:

example 2

A coating is prepared from the following components:

example 3

A coating is prepared from the following components:

example 4

A coating is prepared from the following components:

example 5

A coating is prepared from the following components:

comparative example 1

A coating is prepared from the following components:

comparative example 2

A coating is prepared from the following components:

comparative example 3

A coating is prepared from the following components:

comparative example 4

A coating is prepared from the following components:

the coatings provided in examples 1 to 5 and comparative examples 1 to 4 were tested, the operation of each test being in accordance with the following criteria:

project	Test standard
		Cross-hatch test/stage	GB/T 9286
Adhesion (pull open method)/MPa	GB/T 5210
		VOC content/(g/L)	GB/T23986 10.4
Sag resistance	GB/T 9264
		Salt spray resistance	GB/T 1771

The experimental results are shown in the following table:

as shown in the table, the coating composition provided by the embodiment of the application is used as a coating layer, and the thickness of a dry film in single-pass spraying construction can reach more than 150 mu m; under the condition of the dry film thickness of 70 mu m, the salt spray resistance index can reach 1000 hours, and under the condition of the dry film thickness of 150 mu m, the salt spray resistance index can reach more than 1600 hours; the interlayer adhesion force with the oil/water-based acrylic finish paint and the oil/water-based polyurethane finish paint is not less than 5MPa.

Various embodiments of the present application may exist in a range format; it should be understood that the description in a range format is merely for convenience and brevity and should not be interpreted as a rigid limitation on the scope of the application. It is therefore to be understood that the range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that a description of a range from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, wherever applicable. In addition, whenever a numerical range is referred to herein, it is meant to include any reference number (fractional or integer) within the indicated range.

In this application, unless otherwise indicated, terms of orientation such as "upper" and "lower" are used specifically to refer to the orientation of the drawing in the figures. In addition, in the description of the present application, the terms "include", "comprise", "comprising" and the like mean "including but not limited to". Relational terms such as "first" and "second", and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Herein, "and/or" describing an association relationship of an association object means that there may be three relationships, for example, a and/or B, may mean: a alone, a and B together, and B alone. Wherein A, B may be singular or plural. Herein, "at least one" means one or more, and "a plurality" means two or more. "at least one", "at least one" or the like refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, "at least one (individual) of a, b, or c," or "at least one (individual) of a, b, and c," may each represent: a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple, respectively.

The foregoing is merely a specific embodiment of the application to enable one skilled in the art to understand or practice the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. a coating composition, it is characterized in that, described coating composition comprises A component and B component, and wherein, the composition of described A component comprises polymagnesium aluminum silicate, amine neutralizer, defoaming agent agent, dispersant, barium sulfate, zinc phosphate, epoxy emulsion, liquid epoxy resin and thickener; the components of the B component include: modified amine water-based epoxy curing agent and anti-flash rust agent.

2. The coating composition according to claim 1, characterized in that, the components of the A component include 0.1-0.8 parts of polymagnesium aluminum silicate, 0.3-0.8 parts of amine neutralizer, 0.2-0.5 parts of defoamer, 0.5-2 parts of dispersant, 15-30 parts of barium sulfate, 6-12 parts of zinc phosphate, 10-30 parts of epoxy emulsion, 20-40 parts of liquid epoxy resin and 0.2 parts of thickener -0.5 part; and/or

The components of the B component include, in parts by mass: 75-85 parts of a modified amine water-based epoxy curing agent and 8-16 parts of an anti-flash rust agent.

3. The coating composition according to claim 2, characterized in that, the composition of the A component also includes 6.5-15 parts of the first solvent; and/or

The components of the B component also include 8-16 parts of the second solvent.

4. The coating composition according to claim 3, characterized in that, the mass ratio of the A component to the B component is (7-9):1.

5. The coating composition according to any one of claims 1 to 4, characterized in that, the epoxy value of the epoxy emulsion is ≤0.25.

6. The coating composition according to any one of claims 1 to 4, wherein the liquid epoxy resin comprises a liquid bisphenol A type epoxy resin; and/or

The liquid bisphenol A epoxy resin includes at least one of E55, E51 and E44.

7. The coating composition according to any one of claims 1 to 4, wherein the defoamer comprises at least one of polydimethylsiloxane and tributyl phosphate; and/or

The dispersant comprises fatty acid polyethylene glycol; and/or

The thickener includes a hydrophobically modified ethoxylated polyurethane polymer.

8. A preparation method of coating composition, is characterized in that, described method comprises:

mixing and grinding the first solvent, polymagnesium aluminum silicate, dispersant, barium sulfate, zinc phosphate and part of the defoamer to obtain the initial mixed material;

Mix the initial mixing material, epoxy emulsion and liquid epoxy resin, and then mix with thickener and remaining defoamer to obtain component A;

Mix the modified amine water-based epoxy curing agent, the second solvent and the anti-flash rust agent to obtain component B;

9. The preparation method of the coating composition according to claim 8, characterized in that, the fineness of the primary mixture is ≤40 μm; and/or

The viscosity of the A component is 2-4 Pa·s.

10. A component, characterized in that, the component comprises a substrate and a coating coated on at least part of the surface of the substrate, the composition of the coating includes A component and B component, wherein the A group The components of the component include polymagnesium aluminum silicate, amine neutralizer, defoamer, dispersant, barium sulfate, zinc phosphate, epoxy emulsion, liquid epoxy resin and thickener; the components of the B component include : Modified amine water-based epoxy curing agent and anti-flash rust agent.