High-corrosion-resistance confining liquid for aluminum alloy transparent conductive oxide film as well as preparation method and application of high-corrosion-resistance confining liquid

Abstract

The invention discloses high-corrosion-resistance confining liquid for an aluminum alloy transparent conductive oxide film and a preparation method and application of the high-corrosion-resistance confining liquid, and belongs to the technical field of aluminum alloy surface hole sealing treatment. 0.8 ml to 1.2 ml of H2SO4, 4.8 g to 5.5 g of Na2SiO3. 9H2O, 2 g to 5 g of PDMDAAC, 3 g to 5 g of Na3PO4 and 0.5 g to 3 g of 8-hydroxyquinoline are dissolved in each liter of pure water; the pH value of the confining liquid is 2.5-3; a workpiece to be sealed is placed in the diluted sealing liquid, ultrasonic vibration is conducted for 30-50 seconds at the room temperature, the workpiece stays in air for 20-30 seconds after being taken out of a bath, then the residual sealing liquid is washed away with pure water, and sealing is completed after drying; according to the invention, PDMDAAC is introduced, and under the combined action of PO < 3 + > and 8-hydroxyquinoline, the whole system has multiple effects of conductivity and corrosion inhibition.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum alloy surface sealing treatment, and relates to a high corrosion-resistant sealing liquid for an aluminum alloy transparent conductive oxide film, and a preparation method and application thereof. Background Art

[0002] The fundamental reason why the transparent oxide film of aluminum alloy has excellent electrical conductivity is that the oxide film layer is thin and has a high porosity. The transparent conductive anodic oxide film of aluminum and aluminum alloy is a porous film with a honeycomb structure, and the number of micropores reaches 4×10 9 ~77×10 9 / square centimeter, the specific surface area is very high, which makes the surface of the oxide film have extremely high chemical activity. The corrosive media or dirt in the air or the use environment can be easily adsorbed into the membrane pores. This leads to the fact that while maintaining good electrical conductivity, it is inevitable that the corrosion resistance cannot be well taken into account. This requires a sealing liquid that does not affect the conductivity and color of the film layer and can significantly reduce the porosity.

[0003] Aluminum alloy sealing liquid is used to seal the transparent conductive anodic oxide film of aluminum alloy. Aluminum alloy sealing liquid can prevent the erosion of corrosive media and improve the corrosion resistance of the oxide film. Unsealed or poorly sealed anodic oxide films may be stained and corroded in a short time. The sealing liquid also has the function of enhancing anti-pollution ability and maintaining a good appearance during use; and it can improve the stability, durability and light resistance of the colored film.

[0004] One method of aluminum alloy sealing liquid is to use the expansion of hydration reaction products, which is a common method of sealing by using the expansion of hydration reaction products. By causing the oxide film to undergo hydration reaction, the product expands and thus seals the micropores. Another method is to use salt hydrolysis for adsorption and inhibition sealing: for example, adding nickel acetate or cobalt acetate salt to pure water to hydrolyze in hot water, hydroxide deposition occurs in the pores of the oxide film, which has a sealing effect. This method can be carried out under slightly lower temperature conditions, and the tank liquid life is longer than boiling water sealing, and the sealing quality is better, but there are environmental issues, because its wastewater contains a large amount of heavy metals nickel and cobalt, and heavy metal ions can cause serious harm to the environment. In order to protect environmental safety, complex and expensive wastewater treatment equipment is required.

[0005] In the existing sealing methods, whether it is pure water boiling sealing or steam high pressure sealing or Ni 2+ Salt colorless sealing cannot achieve the ideal effect. The conventional hydrophobic material film-forming sealing can significantly reduce the conductivity of the film layer while enhancing the corrosion resistance. Some of them have a hydrophobic effect but cannot resist salt spray corrosion. Summary of the invention

[0006] The present invention overcomes the shortcomings of the prior art and proposes a high corrosion resistant sealing liquid for transparent conductive oxide film of aluminum alloy and a preparation method and application thereof; the present invention is achieved through the following technical solutions: High corrosion resistant sealing liquid for transparent conductive oxide film of aluminum alloy, each liter of pure water contains the following components: H2SO4 0.8~1.2ml Na2SiO3·9H2O 4.8~5.5g PDMDAAC 2~5g Na3PO4 3~5g 8-Hydroxyquinoline 0.5~3g The molecular weight of the PDMDAAC is less than 30,000, and the molar percentage of PDMDAAC is 30%; The pH of the blocking solution is 2.5-4.

[0007] Preferably, H2SO4 is 1 ml and Na2SiO3·9H2O is 5 g.

[0008] The method for preparing a high corrosion-resistant sealing liquid for an aluminum alloy transparent conductive oxide film is characterized by comprising the following steps: S1. Dissolve Na2SiO3·9H2O in a portion of pure water, cool to room temperature for standby use, and obtain liquid A; S2, add H2SO4 dropwise to a portion of pure water, stirring while dropping, and then cool to room temperature for use, to obtain liquid B; S3, PDMDAAC, Na3PO4, and 8-hydroxyquinoline were added to a portion of pure water in sequence under stirring to fully dissolve, and the pH was adjusted to between 1.5 and 2 with H2SO4 to obtain liquid C; S4. Add liquid A to liquid B under stirring, cool to room temperature for later use, and obtain liquid D; S5. Add liquid D to liquid C under stirring and mix thoroughly to obtain liquid E; S6. Let the E solution stand for more than 1 hour, filter and take the clarified liquid, adjust the pH to between 2.5 and 3 with H3PO4 / NH3·H2O and add pure water to 1L to obtain a concentrated blocking solution.

[0009] Preferably, in step S1, Na2SiO3·9H2O is dissolved in 100 ml of pure water; in step S2, H2SO4 is added dropwise to 300 ml of pure water; in step S3, PDMDAAC, Na3PO4, and 8-hydroxyquinoline are added sequentially to 500 ml of pure water under stirring.

[0010] For the application of high corrosion resistance sealing liquid for transparent conductive oxide film of aluminum alloy, add 0.3~0.6ml H3PO4 and 0.8~1.2ml sealing liquid to pure water and stir evenly, add pure water to 1L, adjust pH=2.5, and obtain diluted sealing liquid; Place the workpiece to be sealed in the diluted sealing liquid, vibrate ultrasonically for 30-50 seconds at room temperature, leave it in the air for 20-30 seconds after coming out of the bath, then rinse it with pure water to remove the residual sealing liquid, and the sealing is completed after drying.

[0011] Preferably, H3PO4 / NH3·H2O is used to adjust the pH.

[0012] More preferably, the drying is performed at 100-120° C. for 15 min.

[0013] The beneficial effects of the present invention compared with the prior art are as follows: The present invention adopts Na2SiO3·9H2O to react with H2SO4 in an environment of pH <3 to form Na2SO4 and H2SiO3, and a trace amount of PDMDAAC (polydimethyldiallyl ammonium chloride) and Na3PO4 have the effect of preventing H2SiO3 from polymerizing in an acidic environment, so that H2SiO3 maintains a nanometer size, and has an excellent filling and sealing effect on the micropores of the conductive oxide film under the action of ultrasound.

[0014] In the acidic environment of 2.5-3.5, the combination of PDMDAAC and Na2HPO4 has a good metal corrosion inhibition effect, and the participation of 8-hydroxyquinoline has a good effect on the corrosion of Cl - Capturing further enhances the metal corrosion inhibition effect of the entire system.

[0015] After the surface sealing liquid is dried, the PDMDAAC is used as a quaternary ammonium salt conductive agent, and the conductivity of the polymer has the ability to maintain conductivity in a low humidity environment. When the dosage is 2g / L, the good requirements can be achieved in the range of RH=20-60%. 3+ The combined effect of hydroxyquinoline and 8-hydroxyquinoline makes the whole system have the multiple effects of conductivity and corrosion inhibition. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a transparency comparison diagram of the actual objects of Example 1 and Comparative Example 1; Figure 2 The conductivity comparison diagram of the actual objects of Example 2 and Comparative Example 2; Figure 3 This is a comparison chart of the corrosion resistance of the actual objects of Example 3 and Comparative Example 3. DETAILED DESCRIPTION

[0017] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail in conjunction with the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. The technical solutions of the present invention are described in detail below in conjunction with the embodiments and the accompanying drawings, but the scope of protection is not limited thereto.

[0018] Example 1 This embodiment provides a high corrosion resistance sealing liquid for aluminum alloy transparent conductive oxide film and its preparation method and application 1. Formula of high corrosion resistant sealing liquid (1000 times concentrated liquid): H2SO4 1ml / L Na2SiO3·9H2O 5g / L PDMDAAC (molecular weight <30,000) 2g / L (the molar percentage of PDMDAAC is 30%) Na3PO4 5g / L 8-Hydroxyquinoline 3g / L H2O to 1L 2. Preparation of sealing agent: (Take the preparation of 1L 1000 times concentrated solution as an example) (1) Take 100 ml of pure water and dissolve 5 g of Na2SiO3·9H2O in it, then cool to room temperature for later use to obtain liquid A; (2) Take 300 ml of pure water and add 1 ml of H2SO4 dropwise into it, stirring while cooling to room temperature, to obtain Solution B; (3) Take 500 ml of pure water, add 15 g of 30% PDMDAAC, 5 g of Na3PO4, and 3 g of 8-hydroxyquinoline into the pure water in sequence while stirring, stir to fully dissolve, and adjust the pH to between 1.5 and 2 with H2SO4 to obtain Solution C; (4) Add liquid A to liquid B while stirring and cool to room temperature for later use to obtain liquid D; (5) Add liquid D to liquid C while stirring and mix thoroughly to obtain liquid E; (6) Allow solution E to stand for more than 1 h, filter out the clear solution, adjust the pH to 2.5 with H3PO4 / NH3·H2O, and add pure water to 1 L to obtain the blocking solution.

[0019] 3. Application of blocking solution Take 500ml pure water, add 0.5ml H3PO4 and 1ml blocking solution, stir evenly, add pure water to 1L, adjust pH to 2.5-3.5 with H3PO4 / NH3·H2O and it is ready for use.

[0020] Place the workpiece to be sealed in the above liquid, vibrate ultrasonically for 30-50 seconds at room temperature, leave it in the air for 20-30 seconds after exiting the bath, then rinse with pure water to remove the residual sealing liquid, and dry it at 100-120℃ / 15min to complete the sealing.

[0021] 4. Principle of the medicinal properties of the sealing solution Na2SiO3·9H2O reacts with H2SO4 to form Na2SO4 and H2SiO3 in an environment with pH < 3, while trace amounts of PDMDAAC and Na3PO4 prevent the polymerization of H2SiO3 in an acidic environment, keeping H2SiO3 in nanometer size; under the action of ultrasound, it has an excellent filling and sealing effect on the micropores of the conductive oxide film.

[0022] At the same time, in an acidic environment of 2.5-3, the combination of PDMDAAC and Na2HPO4 has a good metal corrosion inhibition effect, and the participation of 8-hydroxyquinoline - Capturing further enhances the metal corrosion inhibition effect of the entire system.

[0023] After the surface sealing liquid is dried, the conductivity of PDMDAAC polymer has the ability to maintain conductivity in a low humidity environment. When the dosage of PDMDAAC is 2g / L, it can meet good requirements in the range of RH=20-60%.

[0024] Example 2 This embodiment provides a high corrosion resistance sealing liquid for aluminum alloy transparent conductive oxide film and its preparation method and application 1. Formula of high corrosion resistant sealing liquid (1000 times concentrated liquid): H2SO4 1.2ml / L Na2SiO3·9H2O 5.5g / L PDMDAAC (molecular weight <30,000) 2g / L (the molar percentage of PDMDAAC is 30%) Na3PO4 4g / L 8-Hydroxyquinoline 3g / L Add H2O to 1L The configuration and application method of the blocking solution are the same as those in Example 1.

[0025] Example 3 This embodiment provides a high corrosion resistance sealing liquid for aluminum alloy transparent conductive oxide film and its preparation method and application 1. Formula of high corrosion resistant sealing liquid (1000 times concentrated liquid): H2SO4 1.1ml / L Na2SiO3·9H2O 5.2g / L PDMDAAC (molecular weight <30,000) 3g / L (the molar percentage of PDMDAAC is 30%) Na3PO4 5g / L 8-Hydroxyquinoline 1g / L Add H2O to 1L The configuration and application method of the blocking solution are the same as those in Example 1.

[0026] Comparative Example 1 A formula of blocking solution (1000 times concentrated solution): H2SO4 1ml / L Na2SiO3·9H2O 5g / L PDMDAAC (molecular weight <30,000) 2g / L (the molar percentage of PDMDAAC is 30%) Na3PO4 5g / L Add H2O to 1L The configuration and application method of the blocking solution are the same as those in Example 1.

[0027] Comparative Example 2 A formula of blocking solution (1000 times concentrated solution): H2SO4 1.2ml / L Na2SiO3·9H2O 5.5g / L PDMDAAC (molecular weight <30,000) 15g / L (the molar percentage of PDMDAAC is 30%) Na3PO4 5g / L 8-Hydroxyquinoline 3g / L Add H2O to 1L The configuration and application method of the blocking solution are the same as those in Example 1.

[0028] Comparative Example 3 A formula of blocking solution (1000 times concentrated solution): H2SO4 1.1ml / L Na2SiO3·9H2O 5.2g / L PDMDAAC (molecular weight <30,000) 3g / L (the molar percentage of PDMDAAC is 30%) 8-Hydroxyquinoline 1g / L Add H2O to 1L The configuration and application method of the blocking solution are the same as those in Example 1.

[0029] Experimental Example 1 1. Take six identical 100×100×2 mm 6063 aluminum alloy rolled plates, perform the same natural color conductive oxidation treatment, and then perform sealing treatment using Examples 1-3 and Comparative Examples 1-3, respectively. Perform a transparency comparison test on Example 1 and Comparative Example 1, and use a colorimeter to test. The results are shown in FIG. Figure 1 ; Transparency comparison: Example 1 values: L=53.77, a=9.40, b=-1.52; Comparative Example 1 values: L = 52.40, a = 11.50, b = -2.64; The results show that the colorimeter test value does not change much, indicating that the transparency of Example 1 is not affected and the transparency is good.

[0030] 2. Conductivity comparison test of Example 2 and Comparative Example 2 was conducted by using a DC low resistance tester (the instrument method used for conductivity detection is supplemented). The results are shown in Figure 2 : Example 2 value: 0.525 milliohm; Comparative Example 2 value: 0.502 milliohm.

[0031] 3. The corrosion resistance of Example 3 and Comparative Example 3 was compared by using a salt spray test chamber and the test standard was GJB150A-11. The results are shown in Figure 3 : Example 3 numerical value: 144h result, Comparative Example 3 numerical value; 144h result.

[0032] The above content is a further detailed description of the present invention in combination with a specific preferred embodiment. It cannot be determined that the specific embodiments of the present invention are limited to this. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the present invention, which should be regarded as belonging to the present invention and the scope of patent protection determined by the submitted claims.

Claims

1. A high corrosion resistant sealing liquid for transparent conductive oxide film of aluminum alloy, characterized in that: The following components are dissolved in each liter of pure water: H2SO4 0.8~1.2ml Na2SiO3·9H2O 4.8~5.5g PDMDAAC 2~5g Na3PO4 3~5g 8-Hydroxyquinoline 0.5~3g The molecular weight of the PDMDAAC is less than 30,000, and the molar percentage of PDMDAAC is 30%; The pH of the blocking solution is 2.5-3.

2. The high corrosion resistant sealing liquid for aluminum alloy transparent conductive oxide film according to claim 1, characterized in that: H2SO4 is 1ml, Na2SiO3·9H2O is 5g.

3. The method for preparing a highly corrosion-resistant sealing liquid for an aluminum alloy transparent conductive oxide film according to claim 1 or 2, characterized in that: The following steps are involved: S1. Dissolve Na2SiO3·9H2O in a portion of pure water, cool to room temperature for standby use, and obtain liquid A; S2, add H2SO4 dropwise to a portion of pure water, stirring while dropping, and then cool to room temperature for use, to obtain liquid B; S3, PDMDAAC, Na3PO4, and 8-hydroxyquinoline were added to a portion of pure water in sequence under stirring to fully dissolve, and the pH was adjusted to between 1.5 and 2 with H2SO4 to obtain liquid C; S4. Add liquid A to liquid B under stirring, cool to room temperature for later use, and obtain liquid D; S5. Add liquid D to liquid C under stirring and mix thoroughly to obtain liquid E; S6. Let the E solution stand for more than 1 hour, filter and take the clarified liquid, adjust the pH to between 2.5 and 3 with H3PO4 / NH3·H2O and add pure water to 1L to obtain a concentrated blocking solution.

4. The method for preparing a highly corrosion-resistant sealing liquid for an aluminum alloy transparent conductive oxide film according to claim 3, characterized in that: In step S1, Na2SiO3·9H2O is dissolved in 100 ml of pure water; in step S2, H2SO4 is added dropwise to 300 ml of pure water; in step S3, PDMDAAC, Na3PO4, and 8-hydroxyquinoline are added sequentially to 500 ml of pure water under stirring.

5. The use of the high corrosion resistant sealing liquid for aluminum alloy transparent conductive oxide film according to claim 1 or 2, characterized in that: Add 0.3-0.6 ml of H3PO4 and 0.8-1.2 ml of blocking solution to pure water and stir evenly, add pure water to 1 L, adjust pH to 2.5, and obtain the diluted blocking solution; Place the workpiece to be sealed in the diluted sealing liquid, vibrate ultrasonically for 30-50 seconds at room temperature, leave it in the air for 20-30 seconds after coming out of the bath, then rinse it with pure water to remove the residual sealing liquid, and the sealing is completed after drying.

6. The use of the high corrosion resistant sealing liquid for aluminum alloy transparent conductive oxide film according to claim 5, characterized in that: The pH was adjusted using H3PO4 / NH3·H2O.

7. The use of the high corrosion resistant sealing liquid for aluminum alloy transparent conductive oxide film according to claim 6, characterized in that: The drying is carried out at 100-120° C. for 15 minutes.

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