阅读说明：本技术 冷喷锌超薄型封闭剂及其施工方法 (Cold zinc-spraying ultrathin sealant and construction method thereof ) 是由 赵栋 张诗童 于 2020-12-28 设计创作，主要内容包括：本发明公开了冷喷锌超薄型封闭剂,包括A剂和B剂；所述A剂按质量分数至少包括以下组分：聚醚多元醇40～55份；四氢呋喃聚醚多元醇：15～25份；异氰酸酯：35～45份；环氧树脂5份～10份；磁铁粉5～10份；所述B剂按质量分数至少包括以下组分：环氧树脂：30份～50份；溶剂：30份-60份；助溶剂：0.5份～2份；着色剂：1份～2份；消泡剂：0.5份～1.5份；固化剂：20份～50份；超分子助剂：0.1份～1份；本发明的封闭剂能够在极薄的情况下具有较高的力学性能、屏蔽性能和吸附性能,显著降低了施工成本。(The invention discloses a cold zinc-spraying ultrathin sealant, which comprises an agent A and an agent B; the agent A at least comprises the following components in percentage by mass: 40-55 parts of polyether polyol; tetrahydrofuran polyether polyol: 15-25 parts; isocyanate: 35-45 parts of a solvent; 5-10 parts of epoxy resin; 5-10 parts of magnet powder; the agent B at least comprises the following components in percentage by mass: epoxy resin: 30-50 parts; solvent: 30-60 parts; cosolvent: 0.5 to 2 parts; colorant: 1-2 parts; defoaming agent: 0.5 to 1.5 portions; curing agent: 20-50 parts of a solvent; supramolecular auxiliaries: 0.1 to 1 portion; the sealant disclosed by the invention has higher mechanical property, shielding property and adsorption property under an extremely thin condition, and the construction cost is obviously reduced.)

1. The cold zinc spraying ultrathin sealant is characterized in that:

comprises an agent A and an agent B;

the agent A at least comprises the following components in percentage by mass:

40-55 parts of polyether polyol;

tetrahydrofuran polyether polyol: 15-25 parts;

isocyanate: 35-45 parts of a solvent;

5-10 parts of epoxy resin;

5-10 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 30-50 parts;

solvent: 30-60 parts;

cosolvent: 0.5 to 2 parts;

colorant: 1-2 parts;

defoaming agent: 0.5 to 1.5 portions;

curing agent: 20-50 parts of a solvent;

supramolecular auxiliaries: 0.1 to 1 portion.

2. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the diameter of the magnet powder is 3-7 microns.

3. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the supermolecule auxiliary agent is one or a mixture of polyvinyl alcohol and polyvinyl formal.

4. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50; the epoxy resin is a mixture obtained by mixing one or more of 607 epoxy resin, 604 epoxy resin, 601 epoxy resin, E51 epoxy resin, 828 epoxy resin and 128 epoxy resin according to a certain proportion.

5. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the solvent in the agent B is a mixture obtained by mixing one or more of dimethylbenzene, n-butyl alcohol and ethylbenzene according to a certain proportion; the curing agent is one or a mixture of more than one of NX2018, NX2016 and NX 2015.

6. The cold-spray zinc ultra-thin sealant according to claim 1, wherein: the cosolvent is an organic silane coupling agent.

7. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to a certain proportion.

8. The cold-spray zinc ultra-thin sealant according to claim 1, wherein:

the colorant is titanium dioxide.

9. The construction method of the cold zinc spraying ultrathin type sealing agent adopts the cold zinc spraying ultrathin type sealing agent as claimed in any one of claims 1 to 8, and is characterized in that:

and uniformly spraying the agent A on the surface of the cold-sprayed zinc coating to be sealed, drying to form a stable coating, and then continuously and uniformly spraying the agent B.

10. The method of claim 9, wherein the method comprises the following steps:

the spraying thickness of the agent A is 5-10 microns, and the spraying thickness of the agent B is 5-10 microns.

Technical Field

The invention relates to the technical field of cold zinc spraying corrosion prevention systems, in particular to a cold zinc spraying ultrathin sealant and a construction method thereof.

Background

The cold zinc spraying anticorrosion is a new steel structure anticorrosion technical system, an anticorrosion functional coating of the cold zinc spraying anticorrosion generally only contains less than 4 percent (mass fraction, the same below) of organic auxiliary agent, and the rest (more than 96 percent, even 99 percent) of high-purity zinc, so that the cold zinc spraying anticorrosion has three main advantages compared with the traditional epoxy zinc-rich sealing coating: firstly, the zinc content of the cold-spray zinc coating is far higher than that of the traditional epoxy zinc-rich sealing coating (50-80%), the protection effect per unit mass is higher, and the cold-spray zinc coating has a potential long-acting protection advantage especially in high-humidity and strong-corrosion application environments such as bridges and ports; secondly, the cold spray zinc coating contains less organic additives, is less prone to the problems of phase separation, brittle fracture caused by aging of the organic additives and the like, and meets the strategic requirements of sustainable development; and thirdly, the overall construction difficulty and the construction cost of the cold zinc spraying anticorrosion system are far less than those of the traditional epoxy zinc-rich anticorrosion system. Based on the advantages, the cold zinc spraying anticorrosion technology system is developed rapidly in recent years, successful application cases are increased rapidly, and the cold zinc spraying anticorrosion technology system must gradually replace the traditional epoxy zinc-rich anticorrosion technology and become a new mainstream.

The characteristic of high zinc content of cold spray zinc also puts higher requirements on the design and formulation of the seal coat. At present, the conventional technical means is to continue to use a mature epoxy resin primer system, however, the protection effect is not good in practice, and the adhesion of the primer is further reduced and even the peeling of the paint skin is caused when the primer is applied and constructed on site in high-humidity areas such as bridges and ports, and the like, because the epoxy resin content of a layer to be protected exposed in the air is high after the epoxy zinc-rich primer is constructed, and the good adhesion effect can be obtained by directly constructing the normal epoxy resin sealing paint. However, the content of the organic auxiliary agent in the cold spray zinc coating is low, the protective layer can be regarded as a pure metal zinc layer, the intermolecular force between the cured protective layer and the epoxy resin is relatively weak, and if the traditional epoxy resin sealing paint is still applied, the problems of weak bonding, paint film falling and the like are inevitably caused. Based on the background, the national standard of the adhesive force of the existing seal primer for cold zinc spraying is only set to be more than or equal to 3MPa and is far lower than the adhesive force standard (more than or equal to 5MPa, standard number) of the seal primer for epoxy zinc-rich coating, and although the requirement can be met in general occasions, the standard is still difficult to adapt to the practical requirement of long-acting protection in large-humidity occasions such as bridges, ports and the like; and the thickness of the common spray coating needs to be larger, the raw material consumption is huge, and the cost is high. Therefore, there is a strong need and a practical significance to develop an epoxy sealer having a strong adhesion ability even with a material saving, especially in a high humidity application.

Disclosure of Invention

The invention provides a cold-sprayed zinc ultrathin sealing agent aiming at the structural characteristics of a cold-sprayed zinc to-be-protected layer, and the sealing agent can have higher mechanical property, shielding property and adsorption property under the extremely thin condition, so that the construction cost is obviously reduced.

Cold spraying zinc ultra-thin type sealing agent,

comprises an agent A and an agent B;

the agent A at least comprises the following components in percentage by mass:

40-55 parts of polyether polyol;

tetrahydrofuran polyether polyol: 15-25 parts;

isocyanate: 35-45 parts of a solvent;

5-10 parts of epoxy resin;

5-10 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 30-50 parts;

solvent: 30-60 parts;

cosolvent: 0.5 to 2 parts;

colorant: 1-2 parts;

defoaming agent: 0.5 to 1.5 portions;

curing agent: 20-50 parts of a solvent;

supramolecular auxiliaries: 0.1 to 1 portion.

Preferably, the diameter of the magnet powder is 3 to 7 micrometers.

Preferably, the supramolecular auxiliary agent is one or a mixture of polyvinyl alcohol and polyvinyl formal.

Preferably, the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50; the epoxy resin is a mixture obtained by mixing one or more of 607 epoxy resin, 604 epoxy resin, 601 epoxy resin, E51 epoxy resin, 828 epoxy resin and 128 epoxy resin according to a certain proportion.

Preferably, the solvent in the agent B is a mixture obtained by mixing one or more of dimethylbenzene, n-butanol and ethylbenzene according to a certain proportion; the curing agent is one or a mixture of more than one of NX2018, NX2016 and NX 2015.

Preferably, the cosolvent is an organic silane coupling agent.

Preferably, the defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to a certain proportion.

Preferably, the colorant is titanium dioxide.

The construction method of the cold zinc spraying ultrathin type sealing agent adopts the cold zinc spraying ultrathin type sealing agent as claimed in any one of claims 1 to 8, and is characterized in that:

and uniformly spraying the agent A on the surface of the cold-sprayed zinc coating to be sealed, drying to form a stable coating, and then continuously and uniformly spraying the agent B.

Preferably, the spraying thickness of the agent A is 5-10 micrometers, and the spraying thickness of the agent B is 5-10 micrometers.

The invention provides a cold zinc-spraying ultrathin sealant and a construction method thereof, and the cold zinc-spraying ultrathin sealant has the following beneficial effects:

1. according to the invention, through a step-by-step coating mode, the magnetic iron powder is introduced into the first sealing layer to form a magnetic field between the magnetic iron powder and the steel substrate, so that the adsorbability and the binding force of the cold-sprayed zinc layer and the sealing coating are physically increased, the magnetic iron powder is used as a framework of the first sealing layer to enable the first sealing layer to have excellent mechanical properties such as impact resistance and tensile resistance, the auxiliary agent capable of forming strong supermolecule action with the metal coating is reasonably introduced into the second sealing layer, the interaction force between the sealing paint film and the first sealing layer is greatly increased, meanwhile, the first sealing layer is sealed to avoid the corrosion of the magnetic iron powder, and the actual construction shows that the magnetic iron powder has obviously improved adsorbability and shielding performance.

2. When the agent A contains a small amount of epoxy resin, the isocyanic acid radical and the hydroxyl in the epoxy resin generate epoxy group-terminated high molecular substance with urethane group, the residual isocyanic acid radical is cured with moisture, the polarity of the epoxy group is increased, and the adhesive force with a base material is improved.

3. In the invention, the NCO enables the volume fraction of micro-areas formed by the association of hard sections to be increased, which is beneficial to the separation of two phases, thereby improving the physical crosslinking and reducing the capability of various substances to pass through the coating.

4. The seal primer disclosed by the invention can be used for directly sealing cold spray zinc anticorrosive coatings, has strong adhesive force besides the conventional chemical corrosion resistance, can effectively overcome the problems of peeling, brittle fracture and the like of the conventional epoxy seal primer, and is particularly suitable for field construction of bridges, ports and the like in a high-humidity environment. Besides, the epoxy seal primer disclosed by the invention is also suitable for sealing in other occasions, such as concrete and the like, besides the cold zinc spray anticorrosive paint.

Detailed Description

The technical scheme in the embodiment of the invention is clearly and completely described below; it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art without any inventive work are within the scope of the present invention.

Cold spraying zinc ultra-thin type sealing agent,

comprises an agent A and an agent B;

the agent A at least comprises the following components in percentage by mass:

40-55 parts of polyether polyol;

tetrahydrofuran polyether polyol: 15-25 parts;

isocyanate: 35-45 parts of a solvent;

5-10 parts of epoxy resin;

5-10 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 30-50 parts;

solvent: 30-60 parts;

cosolvent: 0.5 to 2 parts;

colorant: 1-2 parts;

defoaming agent: 0.5 to 1.5 portions;

curing agent: 20-50 parts of a solvent;

supramolecular auxiliaries: 0.1 to 1 portion.

Further, the diameter of the magnet powder is 3-7 micrometers.

Furthermore, the supramolecular auxiliary agent is one or a mixture of polyvinyl alcohol and polyvinyl formal.

Further, the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50; the epoxy resin is a mixture obtained by mixing one or more of 607 epoxy resin, 604 epoxy resin, 601 epoxy resin, E51 epoxy resin, 828 epoxy resin and 128 epoxy resin according to a certain proportion.

Further, the solvent in the agent B is a mixture obtained by mixing one or more of dimethylbenzene, n-butanol and ethylbenzene according to a certain proportion; the curing agent is one or a mixture of more than one of NX2018, NX2016 and NX 2015.

Further, the cosolvent is an organic silane coupling agent.

Further, the defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to a certain proportion.

Further, the colorant is titanium dioxide.

The construction method of the cold zinc spraying ultrathin type sealing agent adopts the cold zinc spraying ultrathin type sealing agent as claimed in any one of claims 1 to 8, and is characterized in that:

and uniformly spraying the agent A on the surface of the cold-sprayed zinc coating to be sealed, drying to form a stable coating, and then continuously and uniformly spraying the agent B.

Further, the spraying thickness of the agent A is 5-10 microns, and the spraying thickness of the agent B is 5-10 microns.

Specific examples within the above composition ranges are as follows:

example 1:

the agent A comprises the following components in percentage by mass:

40 parts of polyether polyol;

tetrahydrofuran polyether polyol: 25 parts of (1);

isocyanate: 35 parts of (B);

5 parts of epoxy resin;

10 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 30 parts of (1);

solvent: 30 parts of (1);

cosolvent: 2 parts of (1);

colorant: 2 parts of (1);

defoaming agent: 1.5 parts;

curing agent: 50 parts of a mixture;

supramolecular auxiliaries: 1 part.

The formula comprises the following components:

the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50;

the epoxy resin is a mixture of 607 epoxy resin, 604 epoxy resin and 601 epoxy resin mixed in a ratio of 1:2: 3.

The solvent in the agent B is a mixture obtained by mixing dimethylbenzene, n-butanol and ethylbenzene according to the ratio of 3:4: 1.

The cosolvent is vinyl triethoxysilane.

The defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to the ratio of 2:2: 1.

The curing agent in the agent B is a mixture obtained by mixing NX2018 and NX2016 in a ratio of 1: 2.

The colorant is titanium dioxide.

The supermolecule assistant is polyvinyl alcohol.

The agent A is produced and packaged in advance, the agent B is prepared on site, the agent A is uniformly sprayed on the surface of the cold-sprayed zinc coating to be sealed, and after the stable coating is formed by drying, the agent B is continuously and uniformly sprayed.

The spraying thickness of the agent A is 5 micrometers, and the spraying thickness of the agent B is 10 micrometers.

Example 2:

the agent A comprises the following components in percentage by mass:

55 parts of polyether polyol;

tetrahydrofuran polyether polyol: 15 parts of (1);

isocyanate: 45 parts of (1);

10 parts of epoxy resin;

5 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 50 parts of a mixture;

solvent: 60 parts;

cosolvent: 0.5 part;

colorant: 1 part;

defoaming agent: 0.5 part;

curing agent: 20 parts of (1);

supramolecular auxiliaries: 0.1 part.

The formula comprises the following components:

the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50;

the epoxy resin is a mixture of 607 epoxy resin, 604 epoxy resin and 601 epoxy resin mixed in a ratio of 1:2: 3.

The solvent in the agent B is a mixture obtained by mixing dimethylbenzene, n-butanol and ethylbenzene according to the ratio of 3:4: 1.

The cosolvent is vinyl triethoxysilane.

The defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to the ratio of 2:2: 1.

The curing agent in the agent B is a mixture obtained by mixing NX2018 and NX2016 in a ratio of 1: 2.

The colorant is titanium dioxide.

The supermolecule assistant is polyvinyl alcohol.

The agent A is produced and packaged in advance, the agent B is prepared on site, the agent A is uniformly sprayed on the surface of the cold-sprayed zinc coating to be sealed, and after the stable coating is formed by drying, the agent B is continuously and uniformly sprayed.

The spraying thickness of the agent A is 10 micrometers, and the spraying thickness of the agent B is 5 micrometers.

Example 3:

the agent A comprises the following components in percentage by mass:

50 parts of polyether polyol;

tetrahydrofuran polyether polyol: 20 parts of (1);

isocyanate: 40 parts of a mixture;

7 parts of epoxy resin;

8 parts of magnet powder.

The agent B at least comprises the following components in percentage by mass:

epoxy resin: 40 parts of a mixture;

solvent: 45 parts of (1);

cosolvent: 1.5 parts;

colorant: 1.5 parts;

defoaming agent: 1 part;

curing agent: 35 parts of (B);

supramolecular auxiliaries: 0.6 part.

The formula comprises the following components:

the polyether polyol is Td-2000; the tetrahydrofuran polyether polyol is PTMG-2000; the isocyanate is MDI-50;

the epoxy resin is a mixture of 607 epoxy resin, 604 epoxy resin and 601 epoxy resin mixed in a ratio of 1:2: 3.

The solvent in the agent B is a mixture obtained by mixing dimethylbenzene, n-butanol and ethylbenzene according to the ratio of 3:4: 1.

The cosolvent is vinyl triethoxysilane.

The defoaming agent is a mixture obtained by mixing BYK-359, BYK-356 and BYK-354 according to the ratio of 2:2: 1.

The curing agent in the agent B is a mixture obtained by mixing NX2018 and NX2016 in a ratio of 1: 2.

The colorant is titanium dioxide.

The supermolecule assistant is polyvinyl alcohol.

The agent A is produced and packaged in advance, the agent B is prepared on site, the agent A is uniformly sprayed on the surface of the cold-sprayed zinc coating to be sealed, and after the stable coating is formed by drying, the agent B is continuously and uniformly sprayed.

The spraying thickness of the agent A is 7 micrometers, and the spraying thickness of the agent B is 7 micrometers.

The cold zinc spraying anticorrosion system constructed by the 3 embodiments is compared with a cold zinc spraying coating sold by a certain tap enterprise purchased in the market in a laboratory for performance test, and the test contents are as follows:

1. mechanical testing

The test substrate is Q235 steel with the size of 200mm multiplied by 100mm multiplied by 2mm, the surface of the steel plate reaches Sa2.5 grade (ISO8501-1) through sand blasting treatment, and then the steel plate is cleaned by absolute ethyl alcohol, surface impurities are removed, and the steel plate is dried for standby.

Firstly, cold spray zinc spraying is carried out, then the seal primers prepared according to the formula of the 3 examples are respectively sprayed on the cold spray zinc layer, and the flexibility, the impact resistance, the adhesive force and the grid marking method are respectively tested together with a control sample.

The flexibility and impact resistance of examples 1 to 3 are not significantly advantageous compared to the control, but the adhesion is greatly improved.

2. Salt spray test

The test substrate is Q235 steel with the size of 200mm multiplied by 100mm multiplied by 2mm, the surface of the steel plate reaches Sa2.5 grade (ISO8501-1) through sand blasting treatment, and then the steel plate is cleaned by absolute ethyl alcohol, surface impurities are removed, and the steel plate is dried for standby.

First, cold zinc spray coating was performed, and then a seal primer formulated according to the formulation of the above 3 examples was sprayed on the cold zinc spray coating, respectively, to scratch a scratch exposing the substrate at the middle position of the coating surface, the size of the scratch being 150mm × 1mm, and four pieces of each test sample, three pieces of which were used as a reference, were prepared for the test, together with the control samples. The corrosion and the blistering phenomenon of the scratches on the surface of the coating are regularly observed and regularly recorded by a digital camera, and the results after 2000h salt spray test are summarized as follows:

although the cross section of the control sample is still flat, the phenomenon of incompact is observed by microscopic observation, bubbles are generated, gaps with different lengths are generated, and in addition, the EDS energy spectrum element discovers Fe, which indicates that corrosion products of iron appear in the coating, the substrate part is corroded, the corrosion protection performance of the coating is lost, while the examples 1 to 3 do not obviously suffer from corrosion, and the A agent of the examples 1 to 3 contains magnet powder, but because of the step coating of the B agent, Fe is not precipitated on the surface layer in the long-time salt spray test.

3. Electrochemical testing

Electrochemical impedance spectroscopy measurement of the coating layer adopts Q235 steel as a base material, the size is 10mm multiplied by 3mm,

and (3) polishing the surface by using 400# SiC sand paper, cleaning by using absolute ethyl alcohol, removing impurities on the surface, and airing for later use. Firstly, cold zinc spraying is carried out, then the seal primers prepared according to the formula of the 3 examples are respectively sprayed on the cold zinc spraying layer, the other group of the test samples are sprayed, the electrochemical impedance measurement frequency is 10-10 Hz, the disturbance voltage is 20mV, the test solution is 3.5 wt% NaCl solution, and the test temperature is room temperature. To prevent interference from external signals, the measurement of electrochemical impedance spectra was performed in a faraday electromagnetic shield.

The test structure is summarized as follows:

the shielding and cathodic protection of examples 1 to 3 are significantly longer lasting than the control.

From the above, the mechanical property, the corrosion resistance and the electrochemical property of the cold spray zinc corrosion prevention system can be obviously improved by adopting the formula and the construction method. Can produce remarkable benefits in actual construction.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.