Organic silicon modified solvent-free epoxy anticorrosive paint capable of resisting 250 DEG C and preparation method of organic silicon modified solvent-free epoxy anticorrosive paint

Abstract

The invention relates to a 250 DEG C resistant organosilicon modified solvent-free epoxy anticorrosive paint, which comprises a component A and a component B. The mass ratio of the component A to the component B is 100: (44.4-55.5). The component A is prepared from the following components in parts by weight: 40 to 50 parts of hyperbranched modified epoxy resin, 0 to 20 parts of glass flake, 0 to 20 parts of mica powder, 0 to 20 parts of talcum powder, 0 to 20 parts of calcium sulfate whisker, 5 to 10 parts of pigment, 0.5 to 1.5 parts of organic bentonite, 0.5 to 1.5 parts of silane coupling agent, 0.1 to 0.5 part of dispersing agent, 0.1 to 0.5 part of defoaming agent and 0.1 to 0.5 part of flatting agent; the component B is a mixture of a modified epoxy curing agent and an organic silicon modified amine curing agent; the hyperbranched modified epoxy resin is used as a main film-forming substance and is matched with the modified epoxy curing agent and the organic silicon modified amine curing agent, so that a coating can resist the high temperature of 250 DEG C for a long time and has excellent flexibility, adhesive force and corrosion resistance, and the coating is extremely low in volatile organic matter content and very green and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating and a preparation method thereof. Background Art

[0002] With the continuous development of various fields, the demand for various functional special materials is increasing, and the requirements for new equipment are also increasing. As we all know, the production of a large part of special materials involves high-temperature treatment, which requires the production equipment to be able to withstand a certain high temperature. At present, the main material of most high-temperature resistant equipment is steel, and only a few are composed of titanium alloys or other alloys. This leads to the fact that in the actual material production process, if the main material of the equipment is steel, once it encounters corrosive media, it will cause equipment damage or major accidents, greatly increasing the cost of production materials.

[0003] At present, common high-temperature resistant coatings include inorganic ceramic systems, special functional resins, etc. These materials can withstand temperatures above 1000°C, even exceeding 2000°C. However, the toughness and corrosion resistance of these coatings are very poor, and they can only be used as high-temperature resistant coatings. Organic coatings are very easy to decompose film-forming substances at high temperatures, so there are very few products that can be used as high-temperature resistant coatings. Special polymers such as polyimide and polyetheretherketone are materials that are resistant to high temperatures of 300-500°C, corrosion-resistant, and have excellent mechanical properties, but they cannot be widely used due to their high material costs; common silicone-modified resins can be used as high-temperature resistant coatings with aluminum powder and other ceramic powders, with a maximum temperature resistance of 600°C, but the toughness and corrosion resistance of such products are relatively general. Conventional silicone-modified epoxy resins can only withstand high temperatures of 250°C, but such coatings do not have excellent toughness and corrosion resistance.

[0004] Traditionally used epoxy resins have the characteristics of low cost, excellent toughness, adhesion and anti-corrosion performance, and are widely used in the field of heavy corrosion protection. However, conventional epoxy resins can only withstand 150°C for a short period of time, and phenolic modified epoxy resins can only withstand 200°C for a short period of time. Therefore, it is urgent to propose a low-cost anti-corrosion coating that can withstand a certain high temperature for a long time. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a 250°C resistant silicone-modified solvent-free epoxy anti-corrosion coating. The invention uses a hyperbranched modified epoxy resin as the main film-forming substance, and is matched with a modified epoxy curing agent and a silicone-modified amine curing agent, so that the coating can withstand a high temperature of 250°C for a long time, and the coating has excellent flexibility, adhesion and anti-corrosion properties, and the coating has an extremely low content of volatile organic matter, and is very green and environmentally friendly.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising component A and component B, wherein the mass ratio of component A to component B is 100:44.4-55.5;

[0008] The component A comprises the following components in parts by weight: 40-50 parts of hyperbranched modified epoxy resin, 0-20 parts of glass flakes, 0-20 parts of mica powder, 0-20 parts of talc, 0-20 parts of calcium sulfate whiskers, 5-10 parts of pigment, 0.5-1.5 parts of organic bentonite, 0.5-1.5 parts of silane coupling agent, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of defoamer and 0.1-0.5 parts of leveling agent;

[0009] The component B is a mixture of a modified epoxy curing agent and an organosilicon-modified amine curing agent.

[0010] Preferably, the hyperbranched modified epoxy resin is EV-2098 organosilicon-modified hyperbranched epoxy resin.

[0011] Preferably, the dispersant is BYK-2155 dispersant.

[0012] Preferably, the defoaming agent is SN-6368A defoaming agent.

[0013] Preferably, the leveling agent is BYK-354 leveling agent.

[0014] Preferably, the model of the silane coupling agent is 6040.

[0015] Preferably, the type of the organic bentonite is 200B.

[0016] Preferably, the pigment is a mixture of titanium dioxide and organic black pigment, wherein the mass ratio of titanium dioxide to organic black pigment is 25:1.

[0017] Preferably, the component B is formed by mixing 13.1 to 16.3 parts by weight of epoxy curing agent 2652 and 31.3 to 39.2 parts by weight of organosilicon modified amine curing agent EV-B303.

[0018] The present invention also provides a method for preparing a 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following steps:

[0019] S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 800-1500 r / min for 3-5 minutes; then sequentially add glass flakes, talcum powder, mica powder, calcium sulfate whiskers, and pigment into a dispersion container for dispersion at a speed of 1500-3000 r / min for 10-20 minutes to obtain component A;

[0020] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0021] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The hyperbranched modified epoxy resin selected by the present invention has a lower viscosity (1000-2000mPs / 25°C) and better heat resistance than ordinary resins. The resin is used as the main film-forming substance, and an anti-corrosion product can be prepared without adding a diluent. This is because the hyperbranched modified epoxy resin used in the present invention is obtained by modifying epoxy resin with multifunctional silicone small molecules. The heat resistance of the film-forming substance is improved by introducing molecular segments with higher bond energy into the epoxy resin. The resin center is a multifunctional silicone small molecule, and the epoxy resin is used as a branch segment to form a hyperbranched molecular structure. In addition, due to the large steric hindrance between the resin molecules, the gaps between the resin molecules are large, and there is no molecular entanglement problem, so it has a lower viscosity.

[0024] (2) The present invention uses a mixture of silicone modified amine and modified epoxy curing agent as the main curing agent, which can not only improve the toughness of the coating but also improve the temperature resistance of the coating. This is because the bond energy in the silicone resin is larger than that of the conventional amine curing agent, and its temperature resistance is better; the epoxy curing agent has good toughness and anti-corrosion performance and excellent comprehensive performance. The main reason is that the silicone modified amine is a combination of silicone resin and special amine monomer. The main molecule is silicone, and the special amine monomer serves as a side chain, which can ensure that the coating has good anti-corrosion and temperature resistance, and can also achieve room temperature curing. However, the curing agent has poor toughness when combined with conventional resins. This is because the molecular chain segment of the silicone modified amine is relatively short, and the coating network formed is relatively dense. Therefore, doping the silicone modified amine with an epoxy curing agent with a long molecular chain segment can have a toughening effect and improve the mechanical properties of the coating. DETAILED DESCRIPTION

[0025] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following components in parts by weight;

[0028] 40 parts of hyperbranched modified epoxy resin, 20 parts of glass flakes, 20 parts of talc, 12 parts of calcium sulfate whiskers, 5 parts of pigment, 0.5 parts of organic bentonite, 1.5 parts of silane coupling agent, 0.3 parts of dispersant, 0.2 parts of defoamer, 0.5 parts of leveling agent, 31.3 parts of organosilicon modified amine curing agent, 13.1 parts of modified epoxy curing agent;

[0029] The preparation method of the epoxy anticorrosive coating in this embodiment is:

[0030] S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 800 r / min for 5 minutes; then sequentially add glass flakes, talcum powder, calcium sulfate whiskers, and pigment into a dispersion container for dispersion at a speed of 1500 r / min for 20 minutes to obtain component A;

[0031] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0032] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0033] Example 2

[0034] A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following components in parts by weight;

[0035] 43 parts of hyperbranched modified epoxy resin, 15 parts of glass flakes, 5 parts of mica powder, 16 parts of talc, 10 parts of calcium sulfate whiskers, 8 parts of pigment, 0.7 parts of organic bentonite, 1.2 parts of silane coupling agent, 0.5 parts of dispersant, 0.5 parts of defoamer, 0.1 parts of leveling agent, 33.7 parts of organosilicon modified amine curing agent, 14 parts of modified epoxy curing agent;

[0036] The preparation method of the epoxy anticorrosive coating in this embodiment is:

[0037] S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 1500 r / min for 3 minutes; then sequentially add glass flakes, talcum powder, mica powder, calcium sulfate whiskers, and pigment into a dispersion container for dispersion at a speed of 3000 r / min for 15 minutes to obtain component A;

[0038] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0039] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0040] Example 3

[0041] A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following components in parts by weight;

[0042] 45 parts of hyperbranched modified epoxy resin, 12 parts of glass flakes, 12 parts of mica powder, 13 parts of talc, 5 parts of calcium sulfate whiskers, 10 parts of pigment, 1 part of organic bentonite, 1 part of silane coupling agent, 0.4 parts of dispersant, 0.3 parts of defoamer, 0.3 parts of leveling agent, 35.3 parts of organosilicon modified amine curing agent, 14.7 parts of modified epoxy curing agent;

[0043] The preparation method of the epoxy anticorrosive coating in this embodiment is:

[0044] S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 1000 r / min for 3 minutes; then sequentially add glass flakes, talcum powder, mica powder, calcium sulfate whiskers, and pigment into a dispersion container for dispersion at a speed of 2000 r / min for 10 minutes to obtain component A;

[0045] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0046] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0047] Example 4

[0048] A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following components in parts by weight;

[0049] 48 parts of hyperbranched modified epoxy resin, 9 parts of glass flakes, 20 parts of mica powder, 10 parts of talc, 10 parts of pigment, 1.2 parts of organic bentonite, 0.8 parts of silane coupling agent, 0.2 parts of dispersant, 0.4 parts of defoamer, 0.4 parts of leveling agent, 37.6 parts of organosilicon modified amine curing agent, 15.7 parts of modified epoxy curing agent;

[0050] The preparation method of the epoxy anticorrosive coating in this embodiment is:

[0051] S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 1200 r / min for 4 minutes; then sequentially add glass flakes, talcum powder, and pigment into a dispersion container for dispersion at a speed of 2500 r / min for 13 minutes to obtain component A;

[0052] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0053] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0054] Example 5

[0055] A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, comprising the following components in parts by weight;

[0056] 50 parts of hyperbranched modified epoxy resin, 18 parts of mica powder, 20 parts of calcium sulfate whiskers, 9.6 parts of pigment, 1.5 parts of organic bentonite, 0.5 parts of silane coupling agent, 0.1 parts of dispersant, 0.1 parts of defoamer, 0.2 parts of leveling agent, 39.2 parts of organosilicon modified amine curing agent, 16.3 parts of modified epoxy curing agent;

[0057] The preparation method of the epoxy anticorrosive coating in this embodiment is:

[0058] S1, sequentially adding hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 1300 r / min for 5 minutes; then sequentially adding calcium sulfate whiskers and pigment into a dispersion container for dispersion at a speed of 1700 r / min for 20 minutes to obtain component A;

[0059] S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B;

[0060] S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

[0061] In the above embodiments, the hyperbranched modified epoxy resin is EV-2098 organosilicon-modified hyperbranched epoxy resin;

[0062] The dispersant is BYK-2155 dispersant;

[0063] The defoamer is SN-6368A defoamer;

[0064] The leveling agent is BYK-354 leveling agent;

[0065] The model of the silane coupling agent is 6040;

[0066] The model of the organobentonite is 200B;

[0067] The pigment is a mixture of titanium dioxide and organic black pigment, wherein the mass ratio of titanium dioxide to organic black pigment is preferably 25:1;

[0068] The modified epoxy curing agent model is 2652, and the silicone modified amine curing agent model is EV-B303;

[0069] The above raw materials can be purchased on the market, among which the hyperbranched modified epoxy resin EV-2098 and the organosilicon modified amine curing agent EV-B303 are preferably from Yierfu Chemical Co., Ltd., and the SN-6368A organosilicon defoaming agent is preferably from Shenzhu Chemical Co., Ltd.

[0070] Comparative Example 1

[0071] No modified epoxy curing agent is included, and the rest is the same as in Example 3.

[0072] Comparative Example 2

[0073] No organosilicon-modified amine curing agent is included, and the rest is the same as in Example 3.

[0074] Comparative Example 3

[0075] The hyperbranched modified epoxy resin was replaced by phenolic modified epoxy resin, and the rest was the same as in Example 3.

[0076] Comparative Example 4

[0077] The organosilicon-modified amine curing agent and the modified epoxy curing agent were replaced by phenolic amine curing agent, and the rest was the same as in Example 3.

[0078] Comparative Example 5

[0079] The hyperbranched modified epoxy resin is replaced by a phenolic modified epoxy resin, and the organosilicon modified amine curing agent and the modified epoxy curing agent are both replaced by a phenolic amine curing agent. The rest is the same as in Example 3.

[0080] In order to better understand the excellent performance of the present invention, the coatings prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were tested for performance:

[0081] Solid content: Determined in accordance with GB / T 1725-2007 "Determination of non-volatile matter content of paints, varnishes and plastics";

[0082] VOC content: Determined in accordance with GB / T 23985-2009 “Paints and varnishes - Determination of volatile organic compound (VOC) content - Difference method”;

[0083] Adhesion: measured according to GB / T 1720-2020 "Paint film circle test";

[0084] Salt spray resistance: Determined in accordance with GB / T 1771-1991 "Determination of neutral salt spray resistance of paints and varnishes";

[0085] Liquid medium resistance: Determined in accordance with GB / T 9274-1988 "Determination of liquid medium resistance of paints and varnishes";

[0086] Impact strength: measured in accordance with GB / T 1732-1993 "Determination of impact resistance of paint films";

[0087] Flexibility: Determined in accordance with GB / T 1731-1993 “Determination of paint film flexibility”;

[0088] The test results are shown in Table 1:

[0089] Table 1 Coating performance test results

[0090]

[0091]

[0092] As shown in Table 1, the anticorrosive coating provided by the present invention can withstand a high temperature of 250° C. for a long time. This is because the hyperbranched modified epoxy resin and the silicone modified amine curing agent can synergistically significantly improve the heat resistance of the coating, and when a portion of the long-chain segment epoxy curing agent is added thereto, the crosslinking density of the coating is reduced and the toughness of the coating is improved.

[0093] It can be seen from the test results of Comparative Examples 1-2 that when the hyperbranched modified epoxy resin is used only in synergy with the organosilicon modified amine curing agent, the temperature resistance and anticorrosion performance of the coating meet the requirements, but the toughness of the coating is poor. When the hyperbranched modified epoxy resin is used only in synergy with the epoxy curing agent, the anticorrosion performance and toughness of the coating meet the requirements, but the acid resistance and temperature resistance are poor.

[0094] The above comparative examples 3-5 prove that it is difficult for conventional phenolic modified epoxy resin, phenolic amine curing agent and epoxy curing agent to simultaneously take into account long-term resistance to high temperature of 250° C., corrosion resistance and toughness.

[0095] In the present invention, the dispersants, defoamers, leveling agents, silane coupling agents and pigments mentioned in the embodiments may also be other qualified products on the market, but the products used in the above embodiments have better effects.

[0096] The specific embodiments of the present invention enable those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0097] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating, characterized in that: It comprises component A and component B, wherein the mass ratio of component A to component B is 100:44.4-55.5; The component A comprises the following components in parts by weight: 40-50 parts of hyperbranched modified epoxy resin, 0-20 parts of glass flakes, 0-20 parts of mica powder, 0-20 parts of talc, 0-20 parts of calcium sulfate whiskers, 5-10 parts of pigment, 0.5-1.5 parts of organic bentonite, 0.5-1.5 parts of silane coupling agent, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of defoamer and 0.1-0.5 parts of leveling agent; The component B is a mixture of a modified epoxy curing agent and an organosilicon-modified amine curing agent.

2. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The hyperbranched modified epoxy resin is EV-2098 organosilicon-modified hyperbranched epoxy resin.

3. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The dispersant is BYK-2155 dispersant.

4. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The defoamer is SN-6368A defoamer.

5. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The leveling agent is BYK-354 leveling agent.

6. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The model of the silane coupling agent is 6040.

7. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The model of the organic bentonite is 200B.

8. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The pigment is a mixture of titanium dioxide and organic black pigment, wherein the mass ratio of titanium dioxide to organic black pigment is 25:

1.

9. The 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The component B is prepared by mixing 13.1 to 16.3 parts of epoxy curing agent 2652 and 31.3 to 39.2 parts of organosilicon modified amine curing agent EV-B303 in parts by weight.

10. The method for preparing the 250°C resistant organic silicon modified solvent-free epoxy anticorrosive coating according to claim 1, characterized in that: The following steps are involved: S1, sequentially add hyperbranched modified epoxy resin, dispersant, defoamer, leveling agent, silane coupling agent, and organic bentonite into a dispersion container for pre-dispersion at a speed of 800-1500 r / min for 3-5 minutes; then sequentially add glass flakes, talcum powder, mica powder, calcium sulfate whiskers, and pigment into a dispersion container for dispersion at a speed of 1500-3000 r / min for 10-20 minutes to obtain component A; S2, mixing the modified epoxy curing agent and the organosilicon modified amine curing agent to obtain component B; S3, mixing the component A and the component B, stirring evenly, to obtain a 250° C. resistant organic silicon modified solvent-free epoxy anticorrosive coating.

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