CN116376332A - Super-smooth inorganic zinc-rich coating - Google Patents

Super-smooth inorganic zinc-rich coating Download PDF

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Publication number
CN116376332A
CN116376332A CN202310352260.4A CN202310352260A CN116376332A CN 116376332 A CN116376332 A CN 116376332A CN 202310352260 A CN202310352260 A CN 202310352260A CN 116376332 A CN116376332 A CN 116376332A
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China
Prior art keywords
inorganic zinc
rich coating
smooth
rich
ultra
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Pending
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CN202310352260.4A
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Chinese (zh)
Inventor
陈根辉
李政
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Guoke New Materials Research Institute Hainan Co ltd
Guoke Xiancai Hefei Technology Co ltd
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Guoke New Materials Research Institute Hainan Co ltd
Guoke Xiancai Hefei Technology Co ltd
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Priority to CN202310352260.4A priority Critical patent/CN116376332A/en
Publication of CN116376332A publication Critical patent/CN116376332A/en
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    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D1/00Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D171/00Coating compositions based on polyethers obtained by reactions forming an ether link in the main chain; Coating compositions based on derivatives of such polymers
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08Anti-corrosive paints
    • C09D5/10Anti-corrosive paints containing metal dust
    • C09D5/106Anti-corrosive paints containing metal dust containing Zn

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  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paints Or Removers (AREA)

Abstract

The invention discloses an ultra-smooth inorganic zinc-rich coating, which comprises an inorganic zinc-rich coating and an ultra-smooth coating, wherein the inorganic zinc-rich coating is prepared from nano modified inorganic zinc-rich coating, and the ultra-smooth coating is formed by pouring low-surface-energy lubricating oil on the surface of the inorganic zinc-rich coating. The super-smooth inorganic zinc-rich coating solves the problem that the inorganic zinc-rich coating has poor anti-corrosion effect under the conditions of high humidity and water contact by introducing the super-smooth coating technology, and further improves the anti-corrosion performance of the inorganic zinc-rich coating.

Description

Super-smooth inorganic zinc-rich coating
Technical Field
The invention discloses an ultra-smooth inorganic zinc-rich coating, and belongs to the technical field of metal corrosion prevention.
Background
Steel is used as engineering material widely applied and is spread over the aspects of people's production and life. Statistics show that the steel loss caused by corrosion is up to 10% of the total yield worldwide each year, and the economic loss caused by steel corrosion accounts for about 3.5% of the total national production value. Therefore, it is necessary to apply corrosion protection measures to steel products, wherein applying corrosion protection paint is the most efficient, economical and common practice.
The alcohol-soluble inorganic zinc-rich paint takes tetraethoxysilane as a film forming substance, forms an iron-zinc silicate complex coating by cross-linking reaction with zinc powder and surface iron atoms, covers the surface of steel, protects the steel together through electrochemical protection and shielding, and has excellent corrosion resistance. However, because of the high zinc powder content in the coating, the coating has a porous structure, and meanwhile, the coating has hydrophilicity, water and corrosive media dissolved in the water can be easily contacted with the steel substrate, so that the coating cannot be directly used in the corrosion prevention field under the high humidity or water contact environment.
The super-slip coating is a new bionic material. The concept of liquid infusion of porous surfaces was first proposed by the university of harvard Aizenberg subject group 2011, simulating the principle of nepenthes predating insects on smooth surfaces. The porous structure is infused with the liquid with low surface energy, and the air film in the porous solid is replaced by a liquid film, so that a more stable solid/liquid composite film layer is formed. Because of the low surface energy of the liquid, the environmental liquid has a large contact angle and a small sliding angle on the surface, and is difficult to adhere to or invade the surface, so the surface is also called a super-sliding surface. The liquid film on the ultra-smooth surface can effectively prevent corrosive medium from invading the coating, so that the coating has high-efficiency anticorrosion effect.
The inorganic zinc-rich coating has a porous structure, and if the inorganic zinc-rich coating can be combined with the ultra-smooth coating technology, the coating can effectively prevent the invasion of liquid corrosive medium, and the anti-corrosion effect of the coating under the environment of high humidity and water contact is improved.
Disclosure of Invention
Based on the problems existing in the prior art, the invention provides an ultra-smooth inorganic zinc-rich coating, and aims to solve the problem that the inorganic zinc-rich coating has poor anti-corrosion effect under the conditions of high humidity and water contact by introducing an ultra-smooth coating technology, so that the anti-corrosion performance of the inorganic zinc-rich coating is further improved.
The invention aims at realizing the following technical scheme:
an ultra-smooth inorganic zinc-rich coating is characterized in that: the super-smooth inorganic zinc-rich coating comprises an inorganic zinc-rich coating and a super-smooth coating; the inorganic zinc-rich coating is prepared from nano modified inorganic zinc-rich coating, and the ultra-smooth coating is formed by pouring low surface energy lubricating oil on the surface of the inorganic zinc-rich coating.
Further, the nano modified inorganic zinc-rich paint is obtained by mixing and uniformly stirring a component A and a component B containing hydrophobic nano particles.
Further: the component A comprises the following raw materials in percentage by mass: 10-30% of tetraethoxysilane, 5-10% of small molecular hydrophobe, 0.5-2% of hydrophobic nano particles, 5-20% of filler and 48-76.5% of solvent. And the component B is zinc powder. The mass ratio of the component A to the component B is 1:2-4.
Preferably, the low surface energy lubricating oil is a perfluoropolyether.
Preferably, the small molecular hydrophobic agent in the component A is one or more of perfluorooctyl triethoxysilane, tridecafluorooctyl trimethoxysilane, heptadecafluorodecyl triethoxysilane and heptadecafluorodecyl trimethoxysilane.
Preferably, the hydrophobic nano particles in the component A are hydrophobically modified fumed silica, and the particle size distribution is 10-500 nanometers.
Preferably, the filler in the component A is one or more of zinc oxide, titanium dioxide, mica powder, talcum powder and ferrotitanium powder.
Preferably, the solvent in the component A is one or two of absolute ethyl alcohol and isopropanol.
Preferably, the zinc powder in the component B is 500 mesh zinc powder.
Preferably, the inorganic zinc-rich coating is prepared by stirring and mixing the nano modified inorganic zinc-rich coating component A and the nano modified inorganic zinc-rich coating component B and then brushing, roller coating or spraying.
The beneficial effects of the invention are mainly as follows:
the super-smooth inorganic zinc-rich coating solves the problem that the inorganic zinc-rich coating has poor anti-corrosion effect under the conditions of high humidity and water contact by introducing the super-smooth coating technology, and further improves the anti-corrosion performance of the inorganic zinc-rich coating, and the specific mechanism is as follows: the lubricating oil with low surface energy can be stably stored in micropores of the inorganic zinc-rich coating through nano modification; the existence of the low-surface-energy lubricating oil can effectively prevent the corrosive medium from penetrating the coating, especially under the high-humidity or water-contact environment, so that the corrosion resistance of the coating is improved; the presence of the low surface energy lubricating oil reduces the adhesion of contaminants to the surface of the coating, providing the coating with self-cleaning capabilities. The preparation process of the ultra-smooth inorganic zinc-rich coating is simple and is suitable for large-area construction.
Detailed Description
The following examples of the present invention are described in detail, and are given by taking the technical scheme of the present invention as a premise, and the detailed implementation and specific operation procedures are given, but the protection scope of the present invention is not limited to the following examples.
Example 1
Preparing a nano modified inorganic zinc-rich coating component A: 0.5g of hydrophobic fumed silica (particle size 100 nanometers), 13g of tetraethoxysilane, 5g of perfluorooctyl triethoxysilane, 5g of zinc oxide and 4g of mica powder are added into 50g of absolute ethyl alcohol, and the mixture is mechanically stirred for 30 minutes, so that the nano modified inorganic zinc-rich coating component A is obtained.
Preparing nano modified inorganic zinc-rich paint: 15g of component A is taken, 30g of 500-mesh zinc powder is added into the component A under stirring, and stirring is continued for 15 minutes, so that the usable nano modified inorganic zinc-rich paint is obtained.
Preparing an inorganic zinc-rich coating: the nano modified inorganic zinc-rich paint prepared above was sprayed 2 times on a clean steel plate through an air gun with a pressure of 40psi at a distance of 20cm and a speed of 8cm/s, and then the steel plate was cured at room temperature to obtain an inorganic zinc-rich coating.
Preparing an ultra-smooth inorganic zinc-rich coating: brushing the surface of the inorganic zinc-rich coating obtained in the previous step with perfluoropolyether, and standing for 2 hours to enable the perfluoropolyether oil to fully enter micropores of the inorganic zinc-rich coating, thereby obtaining the ultra-smooth inorganic zinc-rich coating.
The super-smooth inorganic zinc-rich coating is subjected to neutral salt spray resistance test according to GB/T1771-2007, and the coating has no problems of foaming, cracking, peeling, rusting and the like after 2000 hours of test. Contact and sliding angles were measured according to ISO19403-2-2017 and ISO19403-7-2017 and were 133 ° and 4 °, respectively.
Example 2
Preparing a nano modified inorganic zinc-rich coating component A: 1.0g of hydrophobic fumed silica (particle size of 30 nanometers), 20g of tetraethoxysilane, 8g of heptadecafluorodecyl triethoxysilane and 7g of titanium dioxide are added into 60g of isopropanol, and the mixture is mechanically stirred for 30 minutes, so that the nano modified inorganic zinc-rich coating component A is obtained.
Preparing nano modified inorganic zinc-rich paint: 10g of component A is taken, 30g of 500-mesh zinc powder is added into the component A under stirring, and stirring is continued for 15 minutes, so that the usable nano modified inorganic zinc-rich paint is obtained.
Preparing an inorganic zinc-rich coating: the nano modified inorganic zinc-rich coating prepared in the above way is brushed on a clean steel plate for 2 times, and then the steel plate is solidified at room temperature to obtain the inorganic zinc-rich coating.
Preparing an ultra-smooth inorganic zinc-rich coating: brushing the surface of the inorganic zinc-rich coating obtained in the previous step with perfluoropolyether, and standing for 2 hours to enable the perfluoropolyether oil to fully enter micropores of the inorganic zinc-rich coating, thereby obtaining the ultra-smooth inorganic zinc-rich coating.
The above inorganic zinc-rich coating and the ultra-smooth inorganic zinc-rich coating were subjected to neutral salt spray resistance test according to GB/T1771-2007: after 2000 hours of testing, the inorganic zinc-rich coating has the problem of rust, and the ultra-smooth inorganic zinc-rich coating has no problems of foaming, cracking, peeling, rust and the like. Contact angle and sliding angle tests were performed according to ISO19403-2-2017 and ISO 19403-7-2017: the contact angle and the sliding angle of the ultra-smooth inorganic zinc-rich coating are 138 degrees and 3 degrees respectively; the inorganic zinc-rich coating layer shows hydrophilicity, and water drops directly penetrate into the coating layer, so that the contact angle and the sliding angle cannot be measured.
Example 3
Preparing a nano modified inorganic zinc-rich paint component A1: 1.0g of hydrophobic fumed silica (particle size 500 nanometers), 25g of tetraethoxysilane, 6g of heptadecafluorodecyl trimethoxysilane, 2g of tridecafluorooctyl trimethoxysilane, 3g of talcum powder and 3g of ferrotitanium powder are added into a mixed solution of 30g of isopropyl alcohol and 30g of absolute ethyl alcohol, and the mixture is mechanically stirred for 30 minutes, so that the nano modified inorganic zinc-rich paint component A1 is obtained.
Preparing a nano modified inorganic zinc-rich paint component A2: 25g of tetraethoxysilane, 3g of talcum powder and 3g of ferrotitanium powder are added into a mixed solution of 30g of isopropyl alcohol and 30g of absolute ethyl alcohol, and the mixture is mechanically stirred for 30 minutes, so that the nano modified inorganic zinc-rich paint component A2 is obtained.
Preparing nano modified inorganic zinc-rich paint: 10g of component A1 is taken, 40g of 500-mesh zinc powder is added into the component A1 under stirring, and stirring is continued for 15 minutes, so that the nano modified inorganic zinc-rich paint N1 which can be used is obtained.
Preparing an inorganic zinc-rich coating: 10g of component A2 was taken, 40g of 500 mesh zinc powder was added to the stirred component A2, and stirring was continued for 15 minutes to obtain a usable inorganic zinc-rich paint N2.
Preparing an inorganic zinc-rich coating: the nano modified inorganic zinc-rich paint N1 and the inorganic zinc-rich paint N2 prepared above are respectively rolled on a clean steel plate by 2 times of roller coating, and then the steel plate is solidified at room temperature to obtain inorganic zinc-rich coatings C1 and C2.
Preparing an ultra-smooth inorganic zinc-rich coating: brushing the perfluoropolyether on the surfaces of the inorganic zinc-rich coatings C1 and C2 obtained in the previous step, and standing for 2 hours to enable the perfluoropolyether oil to fully enter micropores of the inorganic zinc-rich coatings, so as to obtain ultra-smooth inorganic zinc-rich coatings S1 and S2.
The super-smooth inorganic zinc-rich coating S1 and the super-smooth inorganic zinc-rich coating S2 are subjected to neutral salt spray resistance test according to GB/T1771-2007, and the super-smooth inorganic zinc-rich coating S1 after 2000 hours of test has no problems of bubbling, cracking, peeling, rusting and the like, and the super-smooth inorganic zinc-rich coating S2 has rusting problems. Contact angle and slip angle tests were performed according to ISO19403-2-2017 and ISO19403-7-2017, with the super-slip inorganic zinc-rich coating S1 contact angle and slip angle being 126 ° and 6 °, respectively, and the super-slip inorganic zinc-rich coating S2 contact angle and slip angle being 132 ° and 8 °, respectively.
The above description is illustrative of the invention and is not intended to be limiting, but is to be construed as being included within the spirit and scope of the invention.

Claims (10)

1. An ultra-smooth inorganic zinc-rich coating, which is characterized in that: the super-smooth inorganic zinc-rich coating comprises an inorganic zinc-rich coating and a super-smooth coating; the inorganic zinc-rich coating is prepared from nano modified inorganic zinc-rich coating, and the ultra-smooth coating is formed by pouring low surface energy lubricating oil on the surface of the inorganic zinc-rich coating.
2. The ultra-smooth inorganic zinc-rich coating according to claim 1, wherein: the nano modified inorganic zinc-rich paint is prepared by mixing and uniformly stirring a component A and a component B containing hydrophobic nano particles.
3. The ultra-smooth inorganic zinc-rich coating according to claim 2, wherein: the component A comprises the following raw materials in percentage by mass: 10-30% of tetraethoxysilane, 5-10% of small molecular hydrophobe, 0.5-2% of hydrophobic nano particles, 5-20% of filler and 48-76.5% of solvent; the component B is zinc powder; the mass ratio of the component A to the component B is 1:2-4.
4. The ultra-smooth inorganic zinc-rich coating according to claim 1, wherein: the low surface energy lubricating oil is perfluoropolyether.
5. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the small molecular hydrophobic agent is one or more of perfluorooctyl triethoxysilane, tridecafluorooctyl trimethoxysilane, heptadecafluorodecyl triethoxysilane and heptadecafluorodecyl trimethoxysilane.
6. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the hydrophobic nano particles are hydrophobic fumed silica, and the particle size distribution is 10-500 nanometers.
7. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the filler is one or more of zinc oxide, titanium dioxide, mica powder, talcum powder and ferrotitanium powder.
8. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the solvent is one or two of absolute ethyl alcohol and isopropanol.
9. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the zinc powder is 500-mesh zinc powder.
10. The ultra-smooth inorganic zinc-rich coating according to claim 3, wherein: the preparation method of the inorganic zinc-rich coating is brushing, roller coating or spraying.
CN202310352260.4A 2023-04-04 2023-04-04 Super-smooth inorganic zinc-rich coating Pending CN116376332A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5413628A (en) * 1993-09-22 1995-05-09 Savin; Ronald R. Stable inorganic zinc-powder rich coating composition
CN1498252A (en) * 2001-03-21 2004-05-19 ŵ�����˹ɷ����޹�˾ Anti-fouling compositions with fluorinated alkyl-or alkoxy-containing polymer or oligomer
US20170058130A1 (en) * 2015-08-28 2017-03-02 Battelle Memorial Institute Paintable hydrophobic and lubricant-infused surface coatings and processes for making and using same
WO2018008728A1 (en) * 2016-07-06 2018-01-11 関西ペイント株式会社 Inorganic zinc-rich paint
US20190136073A1 (en) * 2017-11-08 2019-05-09 King Fahd University Of Petroleum And Minerals Substrate with a superhydrophobic coating and a method of fabricating thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5413628A (en) * 1993-09-22 1995-05-09 Savin; Ronald R. Stable inorganic zinc-powder rich coating composition
CN1498252A (en) * 2001-03-21 2004-05-19 ŵ�����˹ɷ����޹�˾ Anti-fouling compositions with fluorinated alkyl-or alkoxy-containing polymer or oligomer
US20170058130A1 (en) * 2015-08-28 2017-03-02 Battelle Memorial Institute Paintable hydrophobic and lubricant-infused surface coatings and processes for making and using same
WO2018008728A1 (en) * 2016-07-06 2018-01-11 関西ペイント株式会社 Inorganic zinc-rich paint
US20190136073A1 (en) * 2017-11-08 2019-05-09 King Fahd University Of Petroleum And Minerals Substrate with a superhydrophobic coating and a method of fabricating thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
郑翔翔等: "醇溶性无机富锌底漆的研制", 《现代涂料与涂装》, vol. 23, no. 11, pages 8 - 10 *

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