1. A thick film anti-cracking inorganic zinc silicate antirust paint comprises a component A and a component B, wherein the component A comprises zinc powder; the method is characterized in that: the component B comprises ethyl silicate or/and ethyl silicate prepolymer, toughening resin, glass fiber, solvent and acid solution;

the toughening resin is one or a combination of more of isocyanate and isocyanate addition compound.

2. The thick film crack-resistant inorganic zinc silicate rust inhibitive paint of claim 1, wherein said acidic solution is one or more of hydrochloric acid solution, sulfuric acid solution and phosphoric acid solution.

3. The thick-film anti-cracking inorganic zinc silicate antirust paint of claim 1, wherein the glass fiber is one or more of ultra-short cut glass fiber and glass fiber powder.

4. The thick film crack-resistant inorganic zinc silicate rust inhibitive paint of claim 1, wherein said ethyl silicate and ethyl silicate prepolymer is one or more of the combination of ES-28, ES-40 and ES-32.

5. The thick-film anti-cracking inorganic zinc silicate antirust paint as claimed in claim 1, wherein the weight ratio of the ethyl silicate prepolymer and/or the ethyl silicate prepolymer to the toughening resin is (57-65): (1-3).

6. The thick film crack resistant inorganic zinc silicate rust inhibitive paint of claim 1, characterized in that: the component B comprises 100 parts of zinc powder according to the weight part ratio;

the component A comprises, by weight, 57-65 parts of ethyl silicate or/and ethyl silicate prepolymer, 24-34 parts of solvent, 3-5 parts of acidic solution, 1-3 parts of toughening resin and 3-5 parts of glass fiber.

7. The thick film crack resistant inorganic zinc silicate rust inhibitive paint of claim 1, characterized in that: the specification of the zinc powder is 500-800 meshes.

8. The thick film crack-resistant inorganic zinc silicate rust inhibitive paint of claim 1, wherein said solvent is absolute ethanol.

9. The thick film crack-resistant inorganic zinc silicate rust inhibitive paint of claim 1, wherein the weight ratio of the component a to the component b is (2.5-3): 1.

10. A method of preparing a thick film crack-resistant inorganic zinc silicate rust inhibitive paint according to any one of claims 1 to 9, wherein the method of preparing component b comprises the steps of:

s100, adding the ethyl silicate or/and ethyl silicate prepolymer and a solvent into a reactor, slowly dropwise adding an acidic solution under the stirring condition, and reacting for 50-70 min;

s200, adding toughening resin and continuously stirring for 90-120 min;

and S300, under the stirring condition, adding glass fiber into the reaction product obtained in the step S200, and dispersing at a high speed until the mixture is uniform to obtain the component B.

Background

The existing alcohol-soluble inorganic zinc silicate antirust paint is prepared by taking an ethyl silicate prepolymer as a main raw material and adding superfine zinc powder, a thickening agent, an antirust pigment filler, a solvent, an auxiliary agent and the like, and has been successfully applied to the field of steel structures such as bridges, storage tanks and the like as a heavy-duty anticorrosive paint due to good corrosion resistance.

However, because the film forming matter in the existing alcohol-soluble inorganic zinc silicate antirust paint is an inorganic Si-O three-dimensional network, the flexibility of the paint film is poor, and the coating is easy to crack or fall off when the paint film is subjected to the action of an external force which deforms the paint film; even in the absence of external force, the coating with an excessively high dry film thickness shrinks during drying to crack the coating, and particularly, the coating cracks are more likely to occur at the inner corner welding seams of the steel structure base material and the welding seams of the web and flange plates of the H-shaped steel. Therefore, it is generally considered that it is necessary to control the film thickness to 80 μm or less to prevent cracking, and it is relatively safe to control the film thickness to 120 μm or less. And when the film thickness is too low, the corrosion resistance is lowered.

In order to solve the problem that the existing alcohol-soluble inorganic zinc silicate antirust paint is easy to crack or fall off, researchers in the field improve the cracking resistance by using organic resin as a base material for blending. Because the alcohol-soluble inorganic zinc silicate antirust paint takes ethanol as a solvent, the organic resin which can be dissolved in the ethanol is limited, the polyvinyl butyral resin is generally adopted, the selectivity is less, the selection is limited, and although the cracking risk can be reduced by adopting the organic resin, the temperature resistance of the coating is reduced, and the addition amount of the organic resin is not too high.

Chinese patent with application number CN201210505277.0 and publication date of 2013, 03 and 20 discloses an organic modified polysilicate and a preparation method thereof, wherein the organic modified polysilicate comprises the following components in percentage by mass: 32-45% of ethyl orthosilicate, 2.5-3% of polyvinyl butyral, 19-36% of isopropanol, 17-20% of ethanol, 5-8% of propylene glycol ethyl ether, 0.3-0.4% of stabilizer, 0.1-0.3% of catalyst and 4-6% of deionized water. The organic modified polysilicate is prepared by cold splicing polyvinyl butyral solution and polysilicate, and the prepared inorganic acid zinc primer can be sprayed at one time with the thickness of 150 mu m and does not crack.

Chinese patent with application number CN201310129205.5 and publication date of 2013, 06 and 12 discloses an inorganic zinc-rich antirust and anti-skid paint which comprises three components of A, B and C, wherein the A component comprises 40-60 parts of solvent, 3-6 parts of water and 30-50 parts of ethyl silicate, the B component comprises 20-30 parts of toughening resin, 5-10 parts of auxiliary agent, 40-60 parts of zinc powder, 30-40 parts of carborundum and 5-10 parts of solvent, the C component comprises aluminum powder, the three components are mixed according to the mass ratio of A to B to C (1-3) to (2-5) to (0.2-0.5), the toughening resin is polyvinyl butyral resin, and the invention is the inorganic zinc-rich antirust paint with the toughening resin being polyvinyl butyral resin.

However, in both of the above-mentioned two chinese patents, the cracking resistance is improved by modifying with an organic resin, and the organic component is further added to improve the cracking resistance continuously, but at the same time, the inorganic film-forming property of the inorganic zinc silicate paint is also changed, which adversely affects the excellent properties of high temperature resistance, chemical resistance, etc.

Disclosure of Invention

To solve the above mentioned background art: the problem that the existing inorganic zinc silicate antirust paint is easy to crack or fall off and the problem that the existing inorganic zinc silicate paint capable of improving the problem of thick film cracking has poor temperature resistance and chemical corrosion resistance.

The invention provides a thick film anti-cracking inorganic zinc silicate antirust paint which comprises a component A and a component B, wherein the component A comprises zinc powder; the component B comprises ethyl silicate or/and ethyl silicate prepolymer, toughening resin, glass fiber, solvent and acid solution; the toughening resin is one or a combination of more of isocyanate and isocyanate addition compound.

The invention improves the cracking resistance by introducing organic phase isocyanate or isocyanate addition compound and inorganic phase glass fiber into ethyl silicate and prepolymer thereof, and the organic phase isocyanate or isocyanate addition compound and the inorganic phase glass fiber have synergistic effect. The hydroxyl-containing polyethyl silicate and prepolymer thereof are hydrolyzed and polymerized under the catalysis of an acidic solution to form hydroxyl-containing polyethyl silicate, when a small amount of isocyanate or isocyanate addition compound is added, the hydroxyl-containing polyethyl silicate and the isocyanate or isocyanate addition compound react to generate aminosilane, and simultaneously a small amount of isocyanato-hydrocarbyl silane can be produced, and the aminosilane and the isocyanato-hydrocarbyl silane have similar structures to silane coupling agents and can be directly used as wetting agents of glass fibers, so that the bonding strength of the glass fibers and film forming materials is higher, the paint film strength is improved, and the occurrence of cracking is reduced. And the inorganic film formed by curing the poly (ethyl silicate) has large brittleness, and the organic chain segment is introduced after the poly (ethyl silicate) reacts with isocyanate or an isocyanate addition product, so that the flexibility is enhanced.

In addition, in order to improve the dispersion performance of the glass fiber in the coating, the glass fiber can be generally subjected to surface treatment by using a silane coupling agent, and then coated with wetting agents such as epoxy resin, acrylic resin and the like so as to improve the dispersion performance of the glass fiber in the coating.

Further, the acid solution is one or more of a hydrochloric acid solution, a sulfuric acid solution and a phosphoric acid solution.

Further, the glass fiber is one or a combination of more of ultra-short cut glass fiber and glass fiber powder.

Further, the ethyl silicate and the ethyl silicate prepolymer are one or a combination of ES-28, ES-40 and ES-32.

Further, the weight ratio of the ethyl silicate or/and ethyl silicate prepolymer to the toughening resin is (57-65): (1-3).

Further, the component B comprises 100 parts of zinc powder according to the weight part ratio; the component A comprises, by weight, 57-65 parts of ethyl silicate prepolymer, 24-34 parts of solvent, 3-5 parts of acidic solution, 1-3 parts of toughening resin and 3-5 parts of glass fiber.

Further, the specification of the zinc powder is 500-800 meshes.

Further, the solvent is absolute ethyl alcohol.

Further, the weight ratio of the component A to the component B is (2.5-3): 1. The invention also provides a preparation method of the thick-film anti-cracking inorganic zinc silicate antirust paint, wherein the preparation method of the component B comprises the following steps:

s100, adding ethyl silicate or/and ethyl silicate prepolymer and a solvent into a reactor, slowly dripping an acidic solution under the stirring condition, and reacting for 50-70 min;

s200, adding toughening resin and continuously stirring for 90-120 min;

and S300, under the stirring condition, adding glass fiber into the reaction product obtained in the step S200, and dispersing at a high speed until the mixture is uniform to obtain the component B.

Compared with the prior art, the thick film anti-cracking inorganic zinc silicate antirust paint provided by the invention has the following technical effects:

the coating film thickness of the coating does not crack up to 180 mu m, and the coating is suitable for thick film spraying construction, can keep the characteristics of inorganic film formation, has unaffected high temperature resistance, still keeps excellent high temperature resistance, and reaches the heat resistance of more than 400 ℃; the corrosion resistance is excellent, and the long-acting heavy-duty anticorrosion application requirements of various steel structures in marine environment can be met;

the raw materials are easy to obtain, the preparation process is simple and convenient, and the method is suitable for large-scale production.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the following description will clearly and completely describe the embodiments of the present invention, and obviously, the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a thick film anti-cracking inorganic zinc silicate antirust paint which comprises a component A and a component B, wherein the component A comprises zinc powder; the component B comprises ethyl silicate or/and ethyl silicate prepolymer, toughening resin, glass fiber, solvent and acid solution; the toughening resin is one or a combination of more of isocyanate and isocyanate addition compound.

Wherein the isocyanate adduct is a product resulting from an isocyanate addition reaction. Preferably, the isocyanate adduct of the toughening resin can be Toluene Diisocyanate (TDI) and trimethylolpropane adduct (TDI-TMP), and the isocyanate in the toughening resin can be hexamethylene diisocyanate biuret (HDI), such as Bayer N75, Asahi chemical formula 75 PX.

Preferably, the acidic solution is one or more of a hydrochloric acid solution, a sulfuric acid solution and a phosphoric acid solution.

Preferably, the acidic solution is a hydrochloric acid solution. Preferably, the concentration of the hydrochloric acid solution is 0.1M.

Preferably, the solvent is absolute ethyl alcohol, a mixed solution of absolute ethyl alcohol and butanol or isopropanol; preferably, the solvent is absolute ethyl alcohol.

Preferably, the glass fiber is one or more of ultra-short cut glass fiber and glass fiber powder.

Preferably, the ethyl silicate and ethyl silicate prepolymer is one or more of ES-28, ES-40 and ES-32.

Preferably, the weight ratio of the ethyl silicate or/and ethyl silicate prepolymer to the toughening resin is (57-65): (1-3).

Preferably, the component B comprises 100 parts of zinc powder according to the weight part ratio; the component A comprises, by weight, 57-65 parts of ethyl silicate prepolymer, 24-34 parts of solvent, 3-5 parts of acidic solution, 1-3 parts of toughening resin and 3-5 parts of glass fiber.

Preferably, the weight ratio of the component A to the component B is (2.5-3) to 1; preferably, the weight ratio of the component A to the component B is 3: 1;

preferably, the specification of the zinc powder is 500-800 meshes.

The invention also provides a preparation method of the thick-film anti-cracking inorganic zinc silicate antirust paint, wherein the preparation method of the component B comprises the following steps: s100, adding ethyl silicate or/and ethyl silicate prepolymer and a solvent into a reactor, slowly dripping an acidic solution under the stirring condition, and reacting for 50-70 min; s200, adding toughening resin and continuously stirring for 90-120 min; and S300, under the stirring condition, adding glass fiber into the reaction product obtained in the step S200, and dispersing at a high speed until the mixture is uniform to obtain the component B.

Preferably, in S100, the acid solution is added dropwise within 30-60 min.

Preferably, in S300, the reaction product obtained in S200 is transferred to a high-speed dispersant, and then glass fiber is added under stirring and dispersed at high speed until uniform.

The invention also provides formulations (unit: parts by weight) of the following examples and comparative examples, as shown in table 1 below:

TABLE 1

In the examples and comparative examples, the weight parts of each raw material were adjusted on the basis of the consistency of the types of the raw material components.

In Table 1, a zinc powder having a mesh number of 600 mesh was used; the ethyl silicate prepolymer is ethyl silicate ES-40; the concentration of the hydrochloric acid solution is 0.1M; the toughening resin is a Bayer company N75 curing agent; the glass fiber is 200-mesh glass fiber powder.

The above examples and comparative examples were prepared as follows:

the preparation method of the component B comprises the following steps: s100, adding ethyl silicate ES-40 and absolute ethyl alcohol into an enamel reaction kettle, sealing the enamel reaction kettle, starting stirring, slowly dropwise adding a hydrochloric acid solution, dropwise adding for 45min, and continuously stirring to react for 60 min; s200, adding a toughening resin (the acrylic resin is replaced in the comparative example 1), and continuously stirring for 100 min; s300, transferring the substances generated after the reaction to a high-speed dispersion machine, adding glass fibers under the stirring condition, and dispersing at a high speed for 10min to uniformly disperse the glass fibers to obtain a component B. The thick film anti-cracking inorganic zinc silicate antirust paint can be prepared by uniformly mixing the component A and the component B according to the weight ratio in the table 1, and can be used for construction.

The following performance tests were performed and the results were obtained using the products obtained in the above examples and comparative examples, as shown in table 2 below:

TABLE 2

As is apparent from the test results in Table 2, comparative example 1 failed to perform the performance test due to unevenness of the paint film caused by poor wettability of the acrylic resin to the glass fiber, as compared with examples 1 to 3, showing that example 1 synergistically acts with the inorganic phase glass fiber to improve the performance by introducing the organic phase isocyanate or isocyanate adduct to the ethyl silicate and prepolymer thereof. The test results of comparative example 2 show that the organic modification alone has no effect on the improvement of the cracking resistance as compared with the organic/inorganic synergy, and the salt spray resistance is affected due to insufficient film thickness.

The inorganic zinc silicate coating with excellent cracking resistance is provided by adopting an organic/inorganic synergistic toughening method, namely the thick-film cracking-resistant inorganic zinc silicate antirust paint is not cracked when the thickness of the thick-film cracking-resistant inorganic zinc silicate antirust paint reaches 180 mu m through one-step spraying, a paint film is not cracked under a 400 ℃ temperature resistance test, the high temperature resistance is excellent, and the heat resistance reaches more than 400 ℃; meanwhile, the salt spray resistance of the product reaches 3000h, the long-acting heavy-duty anticorrosion application requirement of various steel structures in the marine environment is met, and the product can be applied to long-acting anticorrosion protection of the steel structures; and the raw materials are easy to obtain, the preparation process is simple and convenient, and the method is suitable for large-scale production. The main technical indexes of the thick film anti-cracking inorganic zinc silicate antirust paint prepared by the invention are shown in the following table 3:

TABLE 3

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.