CN109023322B - Water-based membrane liquid replacing phosphating liquid and preparation method thereof - Google Patents
Water-based membrane liquid replacing phosphating liquid and preparation method thereof Download PDFInfo
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- CN109023322B CN109023322B CN201811032170.2A CN201811032170A CN109023322B CN 109023322 B CN109023322 B CN 109023322B CN 201811032170 A CN201811032170 A CN 201811032170A CN 109023322 B CN109023322 B CN 109023322B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
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Abstract
An aqueous leather membrane liquid replacing phosphating liquid comprises the following raw materials in parts by weight: 30-100 parts of water, 5-10 parts of polar solvent, 1-3 parts of fatty alcohol-polyoxyethylene ether nonionic surfactant (AEO), 1-5 parts of alkyl trimethyl ammonium chloride cationic surfactant, 10-30 parts of water-based phenolic resin and 20-50 parts of water-based emulsion; the water-soluble phenolic resin with a novel structure replaces the traditional tannic acid as a rust removing and rust converting agent, overcomes the defects of products in the current market, develops a better-performance phosphating solution substitute product integrating oil removal, rust removal, phosphating and passivation, does not contain phosphoric acid, heavy metal and waste acid liquid discharge, is a really environment-friendly product, and is suitable for pretreatment before coating of large-sized workpieces, steel frames, pipelines, metal furniture, doors and windows, vehicles, ships, bridges, equipment and machine tools and the like which are inconvenient to operate in the traditional phosphating.
Description
Technical Field
The invention belongs to the field of chemical treatment and corrosion prevention of the surface of steel, and particularly relates to a water-based leather membrane liquid for replacing phosphating liquid and a preparation method thereof.
Background
The prior surface coating pretreatment of steel products is mainly a phosphating process, and the whole process generally comprises four procedures of oil removal, rust removal, phosphating, passivation and the like. The treatment period is long, a large amount of waste acid liquor containing phosphorus and heavy metals is generated in the process, and on the premise that the environmental protection pressure is severe day by day, a novel product which is environment-friendly and efficient and can replace the traditional phosphating process to realize economic benefits and social benefits is needed to be developed.
Under the background, products integrating four functions of oil removal, rust removal, phosphorization and passivation appear on the market, but the actual effect is poor and satisfactory, and the defects of poor oil removal effect, poor adhesive force, insufficient corrosion resistance and the like are mainly reflected, and in addition, phosphoric acid, heavy metals and the like are also contained.
For example, application No. 201710843595.0 discloses a four-in-one acid-washing phosphating solution formula which contains heavy metals such as tin and molybdenum besides phosphoric acid; application No. 2016103737470 discloses a phosphating solution with comprehensive functions of oil removal, rust removal, phosphating and passivation, which contains heavy metals such as copper, nickel and the like besides phosphoric acid; application No. 2014102123148 discloses a phosphating solution having the functions of removing rust, removing oil, phosphating to form a film and passivating, but containing a phosphoric acid component.
Disclosure of Invention
In order to solve the problems of the prior art, the invention provides a water-based leather membrane liquid replacing phosphating solution and a preparation method thereof, which uses water-soluble phenolic resin with a novel structure to replace the traditional tannic acid as a rust removing and rust converting agent, overcomes the defects of products in the current market, develops a phosphating solution replacing product with better performance, which integrates oil removing, rust removing, phosphating and passivation, does not contain phosphoric acid, heavy metal and does not discharge waste acid liquor, and is really environment-friendly.
In order to achieve the purpose, the invention adopts the following technical scheme:
an aqueous leather membrane liquid replacing phosphating liquid comprises the following raw materials in parts by weight: 30-100 parts of water, 5-10 parts of polar solvent, 1-3 parts of fatty alcohol-polyoxyethylene ether nonionic surfactant (AEO), 1-5 parts of alkyl trimethyl ammonium chloride cationic surfactant, 10-30 parts of water-based phenolic resin and 20-50 parts of water-based emulsion.
Furthermore, the water-based emulsion is a film forming agent, belongs to corrosion-resistant and rust-proof emulsion, and is one or more of acrylic emulsion, PVDC emulsion, polyurethane modified acrylic emulsion and acrylic modified polyurethane dispersion.
Further, the polar solvent is one or more of ethanol, acetone, isopropanol, ethylene glycol dimethyl ether and ethylene glycol diethyl ether.
The invention also provides a preparation method of the aqueous membrane liquid for replacing phosphating liquid, which comprises the following steps:
1) preparation of the aqueous phenolic resin: putting alkylphenol and formaldehyde solution with volume fraction of 37% into a reaction kettle, stirring to dissolve the alkylphenol, then dropwise adding a small amount of alkaline catalyst, heating to 70-90 ℃ for reaction for 2 hours, cooling to 40-50 ℃, then adding acidic catalyst and tannin, and reacting for 1-3 hours to obtain water-soluble phenolic resin;
2) adding the water-soluble phenolic resin obtained in the step 1) into water in a reaction kettle, adding the water-soluble emulsion while stirring, sequentially adding various surfactants after uniformly stirring, and finally dropwise adding an antifoaming agent accounting for 0.2-0.5% of the total amount of the solution to obtain the water-soluble leather membrane liquid replacing the phosphating solution.
Further, the alkylphenol in the step 1) is one or more of tannic acid, triphenyl phenol, mesityl oxide, resorcinol, catechol, phenol, cresol and cardanol.
Further, the alkylphenol in the step 1) is preferably phenols with strong reaction ability with rust, such as tannic acid, triphenyl phenol, mesityl phenol, resorcinol, catechol and the like.
Further, the alkaline catalyst in the step 1) is sodium hydroxide, and the dosage of the alkaline catalyst is 1% of the mass of the alkylphenol.
Furthermore, the acid catalyst in the step 1) is oxalic acid, and the using amount of the acid catalyst is 0.1-0.5% of the mass of the tannin.
Compared with the prior art, the invention has the beneficial effects that:
1) the water solubility of the phenolic resin is lower than that of the tannic acid, so that the product has better water resistance;
2) the molecular weight of the phenolic resin is larger, and the formed black substance has larger molecular weight, so that the protective film is harder and has higher strength;
3) the phenolic resin can form a more compact special structure in directional arrangement in the drying process, and external oxygen and moisture are prevented from permeating the surface of the steel, so that the corrosivity is improved;
4) part of components in the phenolic resin play a role of a surfactant, and the phenolic resin has a better oil removing effect so as to improve the adhesive force to the surface of steel;
5) the phenolic resin and the water-based emulsion have good compatibility, and a protective film with excellent comprehensive performance can be formed;
6) the process is simple and has strong feasibility, can replace four process steps of oil removal, rust removal, phosphorization and passivation which are necessary for the traditional phosphorization liquid treatment process, can greatly save time and cost and improve production efficiency; any common brushing mode can be adopted; the zero discharge of waste liquid can be really realized;
7) the film has good binding power with steel, and has good compatibility with common corrosion-resistant coating or powder coating on the market;
8) the method is suitable for pretreatment before coating of large-scale workpieces, steel frames, pipelines, metal furniture, doors and windows, vehicles, ships, bridges, equipment and machine tools and the like which are inconvenient to operate in the traditional phosphating.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some 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.
An aqueous leather membrane liquid replacing phosphating liquid comprises the following raw materials in parts by weight: 30-100 parts of water, 5-10 parts of polar solvent, 1-3 parts of fatty alcohol-polyoxyethylene ether nonionic surfactant (AEO), 1-5 parts of alkyl trimethyl ammonium chloride cationic surfactant, 10-30 parts of water-based phenolic resin and 20-50 parts of water-based emulsion.
The water-based emulsion is a film forming agent, belongs to corrosion-resistant and rust-resistant emulsion, and is one or more of acrylic emulsion, PVDC emulsion, polyurethane modified acrylic emulsion and acrylic modified polyurethane dispersion.
The polar solvent is one or more of ethanol, acetone, isopropanol, ethylene glycol dimethyl ether and ethylene glycol diethyl ether.
The invention also provides a preparation method of the aqueous membrane liquid for replacing phosphating liquid, which comprises the following steps:
1) preparation of the aqueous phenolic resin: putting alkylphenol and formaldehyde solution with volume fraction of 37% into a reaction kettle, stirring to dissolve the alkylphenol, then dropwise adding a small amount of alkaline catalyst, heating to 70-90 ℃ for reaction for 2 hours, cooling to 40-50 ℃, then adding acidic catalyst and tannin, and reacting for 1-3 hours to obtain water-soluble phenolic resin;
2) adding the water-soluble phenolic resin obtained in the step 1) into water in a reaction kettle, adding the water-soluble emulsion while stirring, sequentially adding various surfactants after uniformly stirring, and finally dropwise adding an antifoaming agent accounting for 0.1-0.5% of the total amount of the solution to obtain the water-soluble leather membrane liquid replacing the phosphating solution.
The alkylphenol in the step 1) is one or more of tannic acid, triphenyl phenol, mesityl oxide, resorcinol, catechol, phenol, cresol and cardanol.
The alkylphenol in the step 1) is preferably phenols with strong reaction capability of tannic acid, triphenyl phenol, mesityl phenol, resorcinol and catechol and rust.
The alkaline catalyst in the step 1) is sodium hydroxide, and the dosage of the alkaline catalyst is 1% of the mass of the alkylphenol.
In the step 1), the acid catalyst is oxalic acid, and the dosage of the acid catalyst is 0.1-0.5% of the mass of tannin.
Example 1:
a preparation method of aqueous membrane liquid replacing phosphating liquid comprises the following steps:
1) preparation of water-soluble phenolic resin: putting 80kg of cardanol and 150kg of formaldehyde solution with volume fraction of 37% into a 1000L reaction kettle, adding a small amount of sodium hydroxide aqueous solution with volume fraction of 20% to enable the pH value to be 8-8.5, then heating to 80 ℃, reacting for 2 hours, and cooling to 40 ℃; adding 300kg of tannic acid and 100kg of catechol, then adding 1kg of oxalic acid, keeping the reaction temperature at 40-50 ℃, and reacting for 3 hours to obtain brown water-soluble phenolic resin.
The reaction is carried out by two steps of reaction of alkali and acid, and reasonable feeding sequence and proportion, the structure arrangement is unique, and meanwhile, the formaldehyde is completely reacted, and the free formaldehyde can be controlled below 500 ppm.
2) Adding 15 parts of the aqueous phenolic resin obtained in the step 1) into 39.8 parts of purified water in a reaction kettle, then adding 30 parts of aqueous polyurethane acrylic emulsion while stirring, sequentially adding 3 parts of MOA-15 nonionic surfactant, 2 parts of hexadecyl trimethyl ammonium chloride cationic surfactant and 10 parts of isopropanol after uniformly stirring, and finally dropwise adding 0.2 part of defoaming agent to obtain the aqueous leather coating liquid for replacing phosphating liquid, wherein the aqueous leather coating liquid is suitable for surface pretreatment of steel products with less iron rust and large oil mass, such as brake discs.
Example 2:
a preparation method of aqueous membrane liquid replacing phosphating liquid comprises the following steps:
1) preparation of water-soluble phenolic resin: putting 80kg of cardanol and 150kg of formaldehyde solution with volume fraction of 37% into a 1000L reaction kettle, adding a small amount of sodium hydroxide aqueous solution with volume fraction of 20% to enable the pH value to be 8-8.5, then heating to 80 ℃, reacting for 2 hours, and cooling to 40 ℃; adding 300kg of tannic acid and 100kg of catechol, then adding 1kg of oxalic acid, keeping the reaction temperature at 40-50 ℃, and reacting for 3 hours to obtain brown water-soluble phenolic resin.
The reaction is carried out by two steps of reaction of alkali and acid, and reasonable feeding sequence and proportion, the structure arrangement is unique, and meanwhile, the formaldehyde is completely reacted, and the free formaldehyde can be controlled below 500 ppm.
2) Adding 20 parts of the aqueous phenolic resin obtained in the step 1) into 39.9 parts of purified water in a reaction kettle, then adding 30 parts of aqueous polyurethane acrylic emulsion while stirring, sequentially adding 1 part of MOA-15 nonionic surfactant, 2 parts of hexadecyl trimethyl ammonium chloride cationic surfactant and 5 parts of isopropanol after uniformly stirring, and finally dropwise adding 0.1 part of defoaming agent to obtain an aqueous leather coating solution for replacing phosphating solution, wherein the aqueous leather coating solution is suitable for surface pretreatment of steel products with less rust.
Example 3:
a preparation method of aqueous membrane liquid replacing phosphating liquid comprises the following steps:
1) preparation of water-soluble phenolic resin: putting 80kg of cardanol and 150kg of formaldehyde solution with volume fraction of 37% into a 1000L reaction kettle, adding a small amount of sodium hydroxide aqueous solution with volume fraction of 20% to enable the pH value to be 8-8.5, then heating to 80 ℃, reacting for 2 hours, and cooling to 40 ℃; adding 300kg of tannic acid and 100kg of catechol, then adding 1kg of oxalic acid, keeping the reaction temperature at 40-50 ℃, and reacting for 3 hours to obtain brown water-soluble phenolic resin.
The reaction is carried out by two steps of reaction of alkali and acid, and reasonable feeding sequence and proportion, the structure arrangement is unique, and meanwhile, the formaldehyde is completely reacted, and the free formaldehyde can be controlled below 500 ppm.
2) Adding 35 parts of the aqueous phenolic resin obtained in the step 1) into 19.9 parts of purified water in a reaction kettle, then adding 34 parts of aqueous PVDC emulsion while stirring, sequentially adding 0.5 part of MOA-15 nonionic surfactant, 0.5 part of hexadecyl trimethyl ammonium chloride cationic surfactant and 2 parts of ethanol after uniformly stirring, and finally dropwise adding 0.1 part of defoaming agent to obtain an aqueous leather membrane solution for replacing phosphating solution, wherein the aqueous leather membrane solution is suitable for surface pretreatment of steel products with much rust.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (6)
1. A preparation method of aqueous membrane liquid replacing phosphating liquid is characterized by comprising the following steps: the water-based skin membrane liquid comprises the following raw materials in parts by weight: 30-100 parts of water, 5-10 parts of polar solvent, 1-3 parts of fatty alcohol-polyoxyethylene ether nonionic surfactant (AEO), 1-5 parts of alkyl trimethyl ammonium chloride cationic surfactant, 10-30 parts of water-based phenolic resin, 20-50 parts of water-based emulsion and a defoaming agent accounting for 0.2-0.5% of the total amount of the solution;
the water-based emulsion is a film forming agent, belongs to corrosion-resistant and rust-proof emulsion, and is one or more of acrylic emulsion, PVDC emulsion and polyurethane emulsion;
the preparation method comprises the following steps:
1) preparation of the aqueous phenolic resin: putting alkylphenol and formaldehyde solution with volume fraction of 37% into a reaction kettle, stirring to dissolve the alkylphenol, then dropwise adding a small amount of alkaline catalyst, heating to 70-90 ℃ for reaction for 2 hours, cooling to 40-50 ℃, then adding acidic catalyst, tannic acid and catechol, and reacting for 1-3 hours to obtain aqueous phenolic resin;
2) adding the water-based phenolic resin obtained in the step 1) into water in a reaction kettle, adding the water-based emulsion while stirring, sequentially adding a fatty alcohol-polyoxyethylene ether nonionic surfactant (AEO), an alkyl trimethyl ammonium chloride cationic surfactant and a polar solvent after uniformly stirring, and finally dropwise adding a defoaming agent accounting for 0.2-0.5% of the total amount of the solution to obtain the water-based leather membrane liquid replacing the phosphating solution.
2. The preparation method of the aqueous membrane liquid for replacing phosphating liquid according to claim 1, which is characterized by comprising the following steps of: the polar solvent is one or more of ethanol, acetone, isopropanol, ethylene glycol dimethyl ether and ethylene glycol diethyl ether.
3. The preparation method of the aqueous membrane liquid for replacing phosphating liquid according to claim 1, which is characterized by comprising the following steps of: the alkylphenol in the step 1) is one or more of tannic acid, triphenyl phenol, mesityl oxide, resorcinol, catechol, phenol, cresol and cardanol.
4. The preparation method of the aqueous membrane liquid replacing phosphating liquid according to claim 3, which is characterized by comprising the following steps of: the alkylphenol in the step 1) is one or more of tannic acid, triphenyl phenol, mesityl phenol, resorcinol and catechol.
5. The preparation method of the aqueous membrane liquid for replacing phosphating liquid according to claim 1, which is characterized by comprising the following steps of: the alkaline catalyst in the step 1) is sodium hydroxide, and the dosage of the alkaline catalyst is 1% of the mass of the alkylphenol.
6. The preparation method of the aqueous membrane liquid for replacing phosphating liquid according to claim 1, which is characterized by comprising the following steps of: in the step 1), the acid catalyst is oxalic acid, and the dosage of the acid catalyst is 0.1-0.5% of the mass of the tannic acid.
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| CN1003869B (en) * | 1987-06-10 | 1989-04-12 | 山东省冶金研究所 | Iron and steel surface painting preprocessing liquor-one step phosphorus liquor |
| JP2009221395A (en) * | 2008-03-18 | 2009-10-01 | Sumitomo Bakelite Co Ltd | Resorcin-modified water soluble phenolic resin for metal-surface treatment, and metal-surface treatment agent |
| CN105017884A (en) * | 2014-04-16 | 2015-11-04 | 镇江德马化工有限公司 | Aqueous rotating rust steel iron surface treatment liquid and preparation method thereof |
| CN104277656A (en) * | 2014-09-16 | 2015-01-14 | 田清峰 | Synthesis process of water-soluble phenolic resin antirust coating |
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