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CN-121991277-A - Water-based acrylic acid metal pretreatment emulsion, preparation method and application thereof

CN121991277ACN 121991277 ACN121991277 ACN 121991277ACN-121991277-A

Abstract

A water-based acrylic acid metal pretreatment emulsion, a preparation method and application thereof belong to the technical field of water-based acrylic acid emulsion and overcome the defects of high deoiling and degreasing cost, environmental pollution and unclean removal in the prior art. The water-based acrylic acid metal pretreatment emulsion comprises, by mass, 100-140 parts of hard monomers, 120-170 parts of soft monomers, 30-60 parts of functional monomers, 5-15 parts of emulsifying agents, 0.1-0.5 part of buffering agents, 1-8 parts of oxidizing agents, 0.1-0.5 part of reducing agents, 10-30 parts of post-addition additives and 600-680 parts of water, wherein the functional monomers comprise acrylamide, and the acrylamide accounts for 1.5% -26% of the sum of the hard monomers, the soft monomers and the functional monomers. The paint film prepared from the aqueous acrylic acid metal pretreatment emulsion has excellent water solubility.

Inventors

  • TANG HAN
  • CHEN YONGHAO
  • ZHANG YANZHEN
  • WANG JIXIANG
  • HAN JIANAN
  • SUN YONGJIAN
  • YU NAICHAO

Assignees

  • 万华化学集团股份有限公司

Dates

Publication Date
20260508
Application Date
20241104

Claims (10)

  1. 1. The aqueous acrylic acid metal pretreatment emulsion is characterized by comprising the following raw materials in parts by mass: The functional monomer comprises acrylamide, wherein the acrylamide accounts for 1.5% -26%, preferably 8% -12% of the sum of the mass of the hard monomer, the mass of the soft monomer and the mass of the functional monomer.
  2. 2. The aqueous metal acrylate pretreatment emulsion of claim 1 wherein at least one of the following conditions is satisfied: (5) 0.2-0.4 parts by mass of a buffering agent; (6) 2-4 parts of oxidant; (7) 0.2-0.4 parts by mass of a reducing agent; (8) Adding 15-25 parts by mass of auxiliary agent; (9) 620-680 parts by mass of water; (10) The mass solid content of the water-based acrylic acid metal pretreatment emulsion is 33-35 wt%; (11) The particle size of the emulsion particles in the aqueous acrylic acid metal pretreatment emulsion is 200-1500nm, preferably 400-800nm; (12) The viscosity of the aqueous acrylic acid metal pretreatment emulsion is 3000-18000cps, preferably 5000-10000cps, more preferably 5000-8000cps.
  3. 3. The aqueous metal acrylate pretreatment emulsion according to claim 1 or 2, characterized in that at least one of the following conditions is fulfilled: (1) The hard monomer comprises one or more of butyl methacrylate, methyl methacrylate and styrene; preferably, the hard monomer is selected from the group consisting of methyl methacrylate and/or butyl methacrylate-based monomers; (2) The soft monomer comprises one or more of isooctyl acrylate, butyl acrylate and ethyl acrylate; (3) The functional monomer also comprises one or more of methyl diacetone acrylamide, hydroxyethyl acrylate, methacrylic acid and acrylic acid.
  4. 4. The aqueous metal acrylate pretreatment emulsion of claim 1 or 2 wherein the emulsifier comprises one or more of sodium allyloxy hydroxypropylsulfonate, sodium dodecyl diphenyloxide disulfonate, polyoxyethylene polystyrene phenol ether, sodium tridecyl alcohol polyoxyethylene ether sulfate, ethoxylated alcohol, sulfonated diphenyloxide tetrapolypropylene derivative sodium salt, sodium allylether hydroxypropylsulfonate, sodium dodecyl sulfate, isomeric tridecyl alcohol polyoxyethylene ether; preferably, the emulsifier comprises one or more of isomeric tridecanol polyoxyethylene ether, ethoxylated alcohol and polyoxyethylene polystyrene phenol ether.
  5. 5. The aqueous metal acrylate pretreatment emulsion according to claim 1 or 2, characterized in that at least one of the following conditions is fulfilled: (1) The buffering agent comprises one or more of sodium bicarbonate, sodium carbonate and ammonium bicarbonate; (2) The oxidant comprises one or more of ammonium persulfate, sodium persulfate, tert-butyl hydroperoxide and hydrogen peroxide; (3) The reducing agent comprises one or more of sodium metabisulfite, isoascorbic acid, sodium hydrosulfite and FF 6; (4) The post-addition auxiliary agent comprises at least any one of a neutralizer, a defoaming agent and a preservative.
  6. 6. A method of preparing an aqueous metal acrylate pretreatment emulsion according to any one of claims 1 to 5 comprising the steps of: Step 1, adding deionized water into a reaction kettle, heating to 80-95 ℃, and adding a first emulsifier into the bottom of the kettle; Step 2, adding a part of pre-emulsion and a first oxidant into a reaction kettle at the temperature of 80-95 ℃ to react for 10-30min to obtain seed emulsion; Step 3, dropwise adding the residual pre-emulsion and the second oxidant into the seed emulsion, wherein the total dropwise adding time is 120-300min; And 4, after the dripping is finished, preserving heat at 80-95 ℃, then cooling to 55-75 ℃, adding a third oxidant and a reducing agent at 55-75 ℃, continuously cooling to below 50 ℃, and adding an auxiliary agent after adding to obtain the water-based acrylic acid metal pretreatment emulsion.
  7. 7. The preparation method of the aqueous acrylic acid metal pretreatment emulsion according to claim 6, wherein in the step 4, heat preservation is carried out for 1-8 hours at 80-95 ℃, preferably 3-5 hours; Or (b) In the step 4, the viscosity and the particle size of the emulsion are monitored while the temperature is kept at 80-95 ℃, the temperature is reduced after the viscosity reaches 3000-18000cps and the particle size reaches 200-1500nm, and preferably, the temperature is reduced after the viscosity reaches 5000-8000cps and the particle size reaches 400-800 nm.
  8. 8. The method of preparing an aqueous metal acrylate pretreatment emulsion according to claim 6 or 7 wherein the pre-emulsion comprises hard monomer, soft monomer, functional monomer, secondary emulsifier, buffer and deionized water.
  9. 9. The method for preparing an aqueous metal acrylate pretreatment emulsion according to claim 8, wherein at least one of the following conditions is satisfied: (1) The first emulsifier and the second emulsifier are independently selected from any one or more of sodium allyloxy hydroxypropyl sulfonate, sodium dodecyl diphenyl ether disulfonate, polyoxyethylene polystyrene phenol ether, sodium tridecyl alcohol polyoxyethylene ether sulfate, ethoxylated C12-14 alcohol, sulfonated diphenyl ether tetrapolypropylene derivative sodium salt, sodium allylether hydroxypropyl sulfonate, sodium dodecyl sulfate and isomeric tridecyl alcohol polyoxyethylene ether; (2) 1-2 parts by mass of a first emulsifier; (3) The second emulsifier is 3-14 parts by mass, preferably 7-13 parts by mass; (4) The first oxidant, the second oxidant and the third oxidant are respectively and independently selected from one or more of ammonium persulfate, sodium persulfate, tert-butyl hydroperoxide and hydrogen peroxide; (5) 0.5-4 parts by mass of a first oxidant; (6) The second oxidant is 1-4 parts by mass; (7) 0.5-4 parts by mass of a third oxidant; (8) In the step 2, a part of the pre-emulsion added into the reaction kettle is 2% -5% of the total mass of the pre-emulsion.
  10. 10. Use of the aqueous metal acrylate pretreatment emulsion according to any one of claims 1 to 5 or the aqueous metal acrylate pretreatment emulsion prepared according to any one of claims 6 to 9 in metal pretreatment.

Description

Water-based acrylic acid metal pretreatment emulsion, preparation method and application thereof Technical Field The invention belongs to the technical field of aqueous acrylic emulsion, and particularly relates to aqueous acrylic metal pretreatment emulsion, a preparation method and application thereof. Background The metal pretreatment emulsion is used for pretreatment of a metal substrate, a resin surface layer with different mechanical, physical and chemical properties with the substrate is formed on the surface of the metal substrate by roller coating, and then the resin surface layer is coated with grease so as to meet special functional requirements of wear resistance, corrosion resistance, oxidation resistance and the like of the metal substrate before final processing and forming, and the metal pretreatment emulsion is widely applied to the fields of household appliances, buildings, ships and the like. The degreasing agent is used for degreasing and degreasing the oil and fat coated on the surface layer of the resin before further deep processing of the metal substrate, and the degreasing agent mainly comprises an alkaline degreasing agent, an emulsifying degreasing agent, a replacement degreasing agent and the like at present, but most of the degreasing agents have the problems of high cost, environmental pollution and the like, and the problems of uncleanness of grease cleaning, great influence on the processing of the metal substrate, particularly the precise substrate, such as shrinkage cavity, falling and the like, are easy to occur. Disclosure of Invention Therefore, the technical problem to be solved by the invention is to overcome the defects of high deoiling and degreasing cost, environmental pollution and uncleanness in the prior art, thereby providing the aqueous acrylic acid metal pretreatment emulsion, the preparation method and the application thereof. For this purpose, the invention provides the following technical scheme. In a first aspect, the invention provides an aqueous acrylic acid metal pretreatment emulsion, which comprises the following raw materials in parts by mass: The functional monomer comprises acrylamide, wherein the acrylamide accounts for 1.5% -26%, preferably 8% -12% of the sum of the mass of the hard monomer, the mass of the soft monomer and the mass of the functional monomer. In one possible embodiment, the water is 620-680 parts by mass; in one possible embodiment, the aqueous metal acrylate pretreatment emulsion has a mass solids content of 33wt% to 35wt%; in a possible embodiment, the particle size of the latex particles in the aqueous metal acrylate pretreatment emulsion is 200-1500nm, preferably 400-800nm; In one possible embodiment, the aqueous metal acrylate pre-treatment emulsion has a viscosity of 3000-18000cps, preferably 5000-10000cps, more preferably 5000-8000cps. In one possible embodiment, the hard monomer comprises one or more of butyl methacrylate, methyl methacrylate, styrene; preferably, the hard monomer is selected from the group consisting of methyl methacrylate and/or butyl methacrylate-based monomers; In one possible embodiment, the soft monomer comprises one or more of isooctyl acrylate, butyl acrylate, ethyl acrylate; In one possible embodiment, the functional monomer further comprises one or more of methyl diacetone acrylamide, hydroxyethyl acrylate, methacrylic acid, and acrylic acid. In one possible embodiment, the emulsifier comprises one or more of sodium allyloxy hydroxypropylsulfonate (COPS-1), sodium dodecyl diphenyloxide disulfonate, polyoxyethylene polystyrene phenol ether (710), sodium trideceth sulfate, ethoxylated C12-14 alcohol (AE-07), sulfonated diphenyloxide tetrapropy derivative sodium salt (2 A1), sodium allylether hydroxypropylsulfonate, sodium dodecyl sulfate, isomeric trideceth polyoxyethylene (3) ether; Alternatively, the ethoxylated alcohol is an ethoxylated C12-14 alcohol. Preferably, the emulsifier comprises one or more of isomeric tridecanol polyoxyethylene (3) ether, ethoxylated C12-14 alcohol (AE-07) and polyoxyethylene polystyrene phenol ether. When emulsion polymerization is used for preparing emulsion, most of the emulsifier can easily form new micelle, new emulsion particles are formed after initiation reaction, the growth of the emulsion particles is inhibited, the particle size distribution is wide, and the product uses the emulsifier with the cloud point lower than the reaction temperature, such as the isomeric tridecanol polyoxyethylene (3) ether, the polyoxyethylene polystyrene phenol ether (710) and the ethoxylated C12-14 alcohol (AE-07), and when the cloud point is higher than the cloud point, the emulsifier has weak self-micelle forming capability, can well inhibit the formation of new micelle, ensures the continuous growth of the emulsion particles, and prepares the emulsion with large size and narrow distribution, thereby ensuring that the product has reduced film compactness in the film forming p