Film former, water-based peelable coating and preparation method

Abstract

The present disclosure provides a film-forming agent, a method for preparing the film-forming agent, a water-based strippable coating, and a method for preparing the water-based strippable coating, and relates to the technical field of coatings. The preparation method of the film-forming agent comprises: mixing a stripping agent, methyl methacrylate, butyl acrylate, and acrylic acid to obtain a first mixed solution; wherein the stripping agent is a polyether-modified organic silicon substance; adding the first mixed solution to a target aqueous solution to obtain an emulsion; adding a first ammonium persulfate aqueous solution to a reactor; adding the emulsion and a second ammonium persulfate aqueous solution to the reactor in multiple times and over a predetermined time period to obtain a second mixed solution; adjusting the pH of the second mixed solution to 6 to 7 to obtain a film-forming agent; wherein the film-forming agent is a polyacrylate emulsion, the polyacrylate emulsion comprises latex particles, and the latex particles are in situ coated with a stripping agent. The present disclosure can avoid the residue of the coating on the substrate material after stripping.

Description

Technical Field

[0001] The present disclosure relates to the technical field of coatings, and in particular to a film former, a method for preparing the film former, a water-based strippable coating, and a method for preparing the water-based strippable coating. Background Art

[0002] In order to prevent materials from being bumped or scratched, spraying a peelable coating on the surface of the material for temporary protection is an effective treatment method. For example, the material can be protected by a peelable coating during transportation, and the coating can be removed from the material when it is delivered for use. Currently, peelable coatings have become the main solution for temporary protection in fields such as ship painting, glass curtain wall installation, metal welding, and transportation of high-precision equipment.

[0003] Strippable coatings contain film formers. Currently, due to the poor quality of the film formers, there may be residues on the surface of the material after the coating is stripped.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to provide a film former, a method for preparing the film former, a water-based strippable coating and a method for preparing the water-based strippable coating, thereby overcoming the problem of residues on the surface of the material after the coating is stripped, at least to a certain extent.

[0006] According to a first aspect of the present disclosure, a method for preparing a film-forming agent is provided, comprising: mixing a stripping agent, methyl methacrylate, butyl acrylate and acrylic acid to obtain a first mixed solution; wherein the stripping agent is a polyether-modified organosilicon-based substance; adding the first mixed solution to a target aqueous solution to obtain a second mixed solution, and subjecting the second mixed solution to a shear emulsification treatment to obtain an emulsion; wherein the target aqueous solution comprises sodium dodecyl sulfate and OP-10; adding a first ammonium persulfate aqueous solution to a reactor; adding the emulsion and a second ammonium persulfate aqueous solution to the reactor multiple times and over a predetermined time period to obtain a second mixed solution; wherein the concentration of the second ammonium persulfate aqueous solution is greater than that of the first ammonium persulfate aqueous solution; adjusting the pH of the second mixed solution to 6 to 7 to obtain a film-forming agent; wherein the film-forming agent is a polyacrylate emulsion, the polyacrylate emulsion comprises latex particles, and the latex particles are in situ coated with the stripping agent.

[0007] Optionally, in parts by mass, the stripping aid is 0.3 to 1 part, methyl methacrylate is 45 to 55 parts, butyl acrylate is 45 to 55 parts, and acrylic acid is 0.3 to 1 part; the target aqueous solution is 50 to 60 parts; wherein the mass ratio of sodium dodecyl sulfate to the target aqueous solution is 5% to 8%, and the mass ratio of OP-10 to the target aqueous solution is 5% to 8%.

[0008] Optionally, adding the first aqueous ammonium persulfate solution into the reactor comprises: adding 25 to 30 parts by mass of the first aqueous ammonium persulfate solution having a concentration of 2% to 3% into the reactor, and adjusting the temperature of the reactor to 70° C. to 75° C.

[0009] Optionally, adding the emulsion and the second aqueous ammonium persulfate solution into the reactor multiple times and over a predetermined time period to obtain a second mixed solution, comprising: adding the emulsion and 50 to 55 parts of the second aqueous ammonium persulfate solution with a concentration of 4% to 5% into the reactor dropwise over 1 to 4 hours, and after the dropwise addition is completed, adjusting the temperature of the reactor to 80° C. to 85° C. and keeping it warm for 3 to 4 hours.

[0010] According to a second aspect of the present disclosure, a film-forming agent is provided, which is prepared by any of the above-mentioned methods for preparing the film-forming agent.

[0011] According to a third aspect of the present disclosure, a method for preparing a water-based strippable coating is provided, using the above-mentioned film-forming agent, comprising: adding a stripping agent to the film-forming agent to obtain a first material; adding a first defoaming agent and an anti-flash rust agent to the first material to obtain a second material; adjusting the pH of the second material to 8 to 9, and adding a thickener to obtain a third material; adding a second defoaming agent to the third material to obtain a water-based strippable coating.

[0012] Optionally, adding a stripping agent to the film-forming agent to obtain a first material comprises: adding a stripping agent to the film-forming agent at a stirring speed of 1200 rpm to 1800 rpm, and stirring for 20 min to 40 min to obtain the first material; wherein the stripping agent is calcium carbonate, and the mass percentage of the stripping agent in the water-based strippable coating is 8.5% to 30%.

[0013] Optionally, the first defoamer and the second defoamer are both polymer non-silicon defoamers, the first defoamer and the second defoamer have the same mass, and the sum of the masses of the first defoamer and the second defoamer in the water-based strippable coating accounts for 0.5% to 1.5% by mass; the anti-flash rust agent is a phosphate complex organic zinc anti-flash rust agent, and the mass percentage of the anti-flash rust agent in the water-based strippable coating is 0.3% to 1.5%.

[0014] Optionally, the thickener comprises an acrylic associative thickener and fumed silica, and the mass percentage of the thickener in the water-based strippable coating is 0.7% to 2.0%.

[0015] According to a fourth aspect of the present disclosure, a water-based strippable coating is provided, which is prepared using the above-mentioned method for preparing the water-based strippable coating.

[0016] According to the scheme of the exemplary embodiment of the present disclosure, in the process of preparing the film-forming agent, a polymer chain polymerization process is involved, wherein a polyether-modified silicone-based substance is introduced in situ into the latex particles. As a stripping aid, the in-situ introduction of the polyether-modified silicone-based substance can form a deep entanglement of the molecular chain with the polymer substance of the film-forming agent, which helps to form these substances into a whole, thereby avoiding the stripping aid remaining on the surface of the base material and improving the strippability of the coating.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0019] Figure 1 A flow chart of a method for preparing a film-forming agent according to an embodiment of the present disclosure is schematically shown.

[0020] Figure 2 A flow chart of a method for preparing a water-based strippable coating according to an embodiment of the present disclosure is schematically shown. DETAILED DESCRIPTION

[0021] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, processes, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0022] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated descriptions will be omitted. The flowcharts shown in the accompanying drawings are only exemplary illustrations and do not necessarily include all the steps. For example, some steps can also be decomposed, while some steps can be combined or partially combined, so the actual execution order may change according to actual conditions. In addition, all the terms "first", "second", "third", etc. below are only for the purpose of distinction and should not be used as limitations of the present disclosure.

[0023] Taking wind turbine installation as an example, wind turbine towers and blades are easily bumped and scratched during transportation. In order to protect their surfaces, temporary protective peelable coating can be sprayed on them, and the coating can be peeled off when they are delivered for operation.

[0024] Strippable coatings can be water-based coatings composed of film formers, stripping agents, fillers, and additives. For example, an acrylic resin emulsion with excellent film-forming properties can be used as a film former. In order to achieve a good stripping effect, in addition to adding stripping agents such as organic silicon fluorine substances or powders such as calcium carbonate, it is also necessary to add a stripping aid with low surface energy to further optimize the stripping effect. However, there is a difference in polarity between the stripping aid and the film former in the water-based coating, which will cause poor compatibility between the two, resulting in the stripping aid easily remaining on the substrate surface after the coating is stripped, which deteriorates the strippability of the coating.

[0025] In order to solve or at least alleviate the above problems, the present disclosure provides a new film-forming agent and a preparation method thereof.

[0026] Figure 1 The flowchart of the method for preparing the film-forming agent according to the embodiment of the present disclosure is schematically shown. Figure 1 The preparation method of the film-forming agent of the embodiment of the present disclosure comprises the following steps:

[0027] S10. Mixing a stripping agent, methyl methacrylate, butyl acrylate and acrylic acid to obtain a first mixed solution.

[0028] In an exemplary embodiment of the present disclosure, the release agent is a polyether-modified organic silicon-based substance. In other words, the release agent mentioned in the present disclosure can also be referred to as a polyether-modified organic silicon-based release agent.

[0029] For uniform mixing of the above materials, by weight, the amount of the stripping aid is 0.3 to 1 part, the amount of methyl methacrylate is 45 to 55 parts, the amount of butyl acrylate is 45 to 55 parts, and the amount of acrylic acid is 0.3 to 1 part.

[0030] S12. Adding the first mixed solution to the target aqueous solution to obtain a second mixed solution, and performing shear emulsification treatment on the second mixed solution to obtain an emulsion.

[0031] In an exemplary embodiment of the present disclosure, the target aqueous solution is 50 to 60 parts, and the target aqueous solution includes sodium lauryl sulfate and OP-10, wherein the mass ratio of sodium lauryl sulfate to the target aqueous solution is 5% to 8%, and the mass ratio of OP-10 to the target aqueous solution is 5% to 8%. For example, the mass of sodium lauryl sulfate and OP-10 can be the same, both of which are 6% of the target aqueous solution.

[0032] S14. Adding a first aqueous solution of ammonium persulfate into the reactor.

[0033] According to some embodiments of the present disclosure, 25 to 30 parts by mass of a first aqueous ammonium persulfate solution having a concentration of 2% to 3% may be added to the reactor, and the temperature of the reactor is adjusted to 70° C. to 75° C.

[0034] The present disclosure does not limit the type of the reactor, which may be, for example, a beaker, a reaction kettle, etc.

[0035] S16. Adding the emulsion and the second aqueous ammonium persulfate solution into the reactor in multiple times and over a predetermined period of time to obtain a second mixed solution.

[0036] In an exemplary embodiment of the present disclosure, the concentration of the second aqueous ammonium persulfate solution is greater than the concentration of the first aqueous ammonium persulfate solution.

[0037] According to some embodiments of the present disclosure, the emulsion and 50 to 55 parts of a second aqueous ammonium persulfate solution having a concentration of 4% to 5% are added dropwise into the reactor in multiple portions over 1 to 4 hours, and after the addition is completed, the temperature of the reactor is adjusted to 80° C. to 85° C. and kept warm for 3 to 4 hours.

[0038] It should be noted that this process includes polymer polymerization reaction, which is carried out in multiple times and over a predetermined period of time in order to control the reaction rate and avoid failure of the film-forming agent preparation due to violent reaction.

[0039] S18. The pH of the second mixed solution is adjusted to 6 to 7 to obtain a film-forming agent.

[0040] Specifically, after the heat preservation in step S16, natural cooling is performed, and after natural cooling to room temperature, the pH of the second mixed solution can be adjusted to 6 to 7 to obtain a film-forming agent. The present disclosure does not limit the type of pH adjusting agent used.

[0041] In an exemplary embodiment of the present disclosure, the film-forming agent is a polyacrylate emulsion, which contains latex particles, and the latex particles are in-situ coated with a release agent. Specifically, the polyether-modified silicone release agent accounts for 0.3% to 1% of the polyacrylate emulsion.

[0042] It should be understood that the polyacrylate emulsion is a liquid composed of water and latex particles. The latex particles are generated by in-situ polymerization of monomers. The disclosed solution adds a polyether-modified silicone-based release agent to the organic monomers used in the polymer, and then polymerizes them into polymer latex particles, thereby forming a polyacrylate emulsion in which the release agent is in-situ coated inside the latex particles.

[0043] Furthermore, the present disclosure provides a film-forming agent, which is prepared by the above-mentioned method for preparing the film-forming agent.

[0044] Figure 2 The flowchart of the method for preparing the water-based strippable coating according to the embodiment of the present disclosure is schematically shown. Figure 2 The method for preparing the water-based peelable coating according to the embodiment of the present disclosure may include the following steps:

[0045] S20. Adding a stripping agent to the film-forming agent to obtain a first material.

[0046] In an exemplary embodiment of the present disclosure, the film-forming agent is the film-forming agent prepared by the above steps S10 to S18, and the mass percentage of the film-forming agent in the entire water-based strippable coating is 65% to 90%. The stripping agent can be calcium carbonate, and the mass percentage of the stripping agent in the entire water-based strippable coating is 8.5% to 30%.

[0047] Specifically, the stripping agent is added to the film-forming agent at a stirring speed of 1200 rpm to 1800 rpm, and stirred for 20 min to 40 min to obtain the first material.

[0048] S22. Adding a first defoaming agent and a flash rust preventer to the first material to obtain a second material.

[0049] In an exemplary embodiment of the present disclosure, the first defoamer and the second defoamer described below are both polymer non-silicon defoamers, the mass of the first defoamer and the second defoamer may be the same, and the mass percentage of the sum of the mass of the first defoamer and the second defoamer in the water-based strippable coating is 0.5% to 1.5%. In addition, the flash rust preventer is a phosphate composite organic zinc flash rust preventer, and the mass percentage of the flash rust preventer in the water-based strippable coating is 0.3% to 1.5%.

[0050] Specifically, after obtaining the first material in step S20, the rotation speed may be reduced to 900 rpm to 1000 rpm, and after adding the first defoaming agent and the anti-flash rust agent to the first material, stirring is performed for 10 min to 15 min to obtain the second material.

[0051] S24. The pH of the second material is adjusted to 8 to 9, and a thickener is added to obtain a third material.

[0052] In an exemplary embodiment of the present disclosure, the thickener comprises an acrylic associative thickener and fumed silica, and the mass percentage of the thickener in the water-based strippable coating is 0.7% to 2.0%.

[0053] Specifically, the pH of the second material can be adjusted to 8 to 9 using 2-amino-2-methyl-1-propanol, the stirring speed is increased to 1200 rpm to 1500 rpm, a thickener is added, and stirring is performed for 30 min to 50 min.

[0054] S26. Adding a second defoaming agent to the third material to obtain a water-based strippable coating.

[0055] According to some embodiments of the present disclosure, after adding the second defoaming agent, stirring is performed for 5 to 10 minutes to obtain a water-based strippable coating.

[0056] Furthermore, the present disclosure also provides a water-based peelable coating, which is prepared by the above-mentioned preparation method of the water-based peelable coating.

[0057] Through the above exemplary scheme of the present disclosure, based on the good compatibility of low surface energy polyether-modified silicone-based peeling aids and vinyl-based oily monomers, the polyether-modified silicone-based peeling aids are in-situ introduced into the interior of polyacrylate latex particles by miniemulsion polymerization. On the one hand, the in-situ introduction of polyether-modified silicone substances during the polymer chain polymerization process promotes the deep entanglement of the molecular chains of the two, thereby avoiding the peeling aid from remaining on the surface of the object; on the other hand, the intrinsic adhesion of the polyacrylate molecules is directly reduced from the microscopic molecular level, giving it excellent peelability.

[0058] The present disclosure is described below through examples and comparative examples.

[0059] Example 1

[0060] First, 0.3 g of a polyether-modified silicone-based stripping agent was fully dissolved in 50 g of methyl methacrylate, 50 g of butyl acrylate and 0.5 g of acrylic acid monomer, and then added to 55 g of a 6% aqueous solution of sodium dodecyl sulfate and OP-10 in an equal mass ratio, and high-speed shear emulsification was performed to obtain an emulsion.

[0061] Next, a three-necked flask with a condensation reflux and stirring device was placed in a 50°C water bath, 28 g of a 2.5% ammonium persulfate aqueous solution was poured into the three-necked flask, and the water bath was heated to 75°C.

[0062] Subsequently, the emulsion and 53 g of 4.5% ammonium persulfate aqueous solution were added dropwise into a three-necked flask within 3 hours. After the addition was completed, the water bath was heated to 80°C and kept warm for 4 hours. After natural cooling, the pH was adjusted to 6.5 with 2-amino-2-methyl-1-propanol. Filtration gave a polyacrylate emulsion in which the latex particles were in situ coated with a polyether-modified silicone-based release agent.

[0063] Then, take 100g of polyacrylate emulsion, add 46.2g of calcium carbonate stripping agent to the emulsion at a speed of 1500rpm and stir for 30min, reduce the speed to 1000rpm, add 1.15g of polymer non-silicon defoaming agent and 2.3g of phosphate composite organic zinc anti-flash rust agent and stir for 30min, adjust the pH to 8.5 with 2-amino-2-methyl-1-propanol, increase the speed to 1500rpm, add 1.55g of gas-phase silicon thickener and 1.55g of acrylic acid associative thickener and stir for 30min, add 1.15g of polymer non-silicon defoaming agent and stir for 5min, and discharge to obtain a water-based strippable coating.

[0064] Example 2

[0065] First, 0.5 g of a polyether-modified silicone-based stripping agent was fully dissolved in 50 g of methyl methacrylate, 50 g of butyl acrylate and 0.5 g of acrylic acid monomer, and then added to 55 g of a 6% aqueous solution of sodium dodecyl sulfate and OP-10 in an equal mass ratio, and high-speed shear emulsification was performed to obtain an emulsion.

[0066] Next, a three-necked flask with a condensation reflux and stirring device was placed in a 50°C water bath, 28 g of a 2.5% ammonium persulfate aqueous solution was poured into the three-necked flask, and the water bath was heated to 75°C.

[0067] Subsequently, the emulsion and 53 g of 4.5% ammonium persulfate aqueous solution were added dropwise into a three-necked flask within 3 hours. After the addition was completed, the water bath was heated to 80°C and kept warm for 4 hours. After natural cooling, the pH was adjusted to 6.5 with 2-amino-2-methyl-1-propanol. Filtration gave a polyacrylate emulsion in which the latex particles were in situ coated with a polyether-modified silicone-based release agent.

[0068] Then, take 100g of polyacrylate emulsion, add 28.67g of calcium carbonate stripping agent to the emulsion at a speed of 1500rpm and stir for 30min, reduce the speed to 1000rpm, add 0.665g of polymer non-silicon defoaming agent and 1.33g of phosphate composite organic zinc anti-flash rust agent and stir for 30min, adjust the pH to 8.5 with 2-amino-2-methyl-1-propanol, increase the speed to 1500rpm, add 1g of gas-phase silicon thickener and 1g of acrylic acid associative thickener and stir for 30min, add 0.665g of polymer non-silicon defoaming agent and stir for 5min, and discharge to obtain a water-based strippable coating.

[0069] Example 3

[0070] First, 1 g of a polyether-modified silicone-based stripping agent was fully dissolved in 50 g of methyl methacrylate, 50 g of butyl acrylate and 0.5 g of acrylic acid monomer, and then added to 55 g of a 6% aqueous solution of sodium dodecyl sulfate and OP-10 in an equal mass ratio, and high-speed shear emulsification was performed to obtain an emulsion.

[0071] Next, a three-necked flask with a condensation reflux and stirring device was placed in a 50°C water bath, 28 g of a 2.5% ammonium persulfate aqueous solution was poured into the three-necked flask, and the water bath was heated to 75°C.

[0072] Subsequently, the emulsion and 53 g of 4.5% ammonium persulfate aqueous solution were added dropwise into a three-necked flask within 3 hours. After the addition was completed, the water bath was heated to 80°C and kept warm for 4 hours. After natural cooling, the pH was adjusted to 6.5 with 2-amino-2-methyl-1-propanol. Filtration gave a polyacrylate emulsion in which the latex particles were in situ coated with a polyether-modified silicone-based release agent.

[0073] Then, 100 g of polyacrylate emulsion was taken, 9.45 g of calcium carbonate stripping agent was added to the emulsion at a speed of 1500 rpm and stirred for 30 min, the speed was reduced to 1000 rpm, 0.275 g of polymer non-silicon defoaming agent and 0.33 g of phosphate composite organic zinc anti-flash rust agent were added and stirred for 30 min, the pH was adjusted to 8.5 with 2-amino-2-methyl-1-propanol, the speed was increased to 1500 rpm, 0.39 g of fumed silicon thickener and 0.39 g of acrylic acid associative thickener were added and stirred for 30 min, 0.275 g of polymer non-silicon defoaming agent was added and stirred for 5 min, and the water-based strippable coating was obtained by discharging.

[0074] Example 4

[0075] First, 0.5 g of a polyether-modified silicone-based stripping agent was fully dissolved in 50 g of methyl methacrylate, 50 g of butyl acrylate and 0.5 g of acrylic acid monomer, and then added to 55 g of a 6% aqueous solution of sodium dodecyl sulfate and OP-10 in an equal mass ratio, and high-speed shear emulsification was performed to obtain an emulsion.

[0076] Next, a three-necked flask with a condensation reflux and stirring device was placed in a 50°C water bath, 28 g of a 2.5% ammonium persulfate aqueous solution was poured into the three-necked flask, and the water bath was heated to 75°C.

[0077] Subsequently, the emulsion and 53 g of 4.5% ammonium persulfate aqueous solution were added dropwise into a three-necked flask within 3 hours. After the addition was completed, the water bath was heated to 80°C and kept warm for 4 hours. After natural cooling, the pH was adjusted to 6.5 with 2-amino-2-methyl-1-propanol. Filtration gave a polyacrylate emulsion in which the latex particles were in situ coated with a polyether-modified silicone-based release agent.

[0078] Then, take 100g of polyacrylate emulsion, add 46.2g of calcium carbonate stripping agent to the emulsion at a speed of 1500rpm and stir for 30min, reduce the speed to 1000rpm, add 1.15g of polymer non-silicon defoaming agent and 2.3g of phosphate composite organic zinc anti-flash rust agent and stir for 30min, adjust the pH to 8.5 with 2-amino-2-methyl-1-propanol, increase the speed to 1500rpm, add 1.55g of gas-phase silicon thickener and 1.55g of acrylic acid associative thickener and stir for 30min, add 1.15g of polymer non-silicon defoaming agent and stir for 5min, and discharge to obtain a water-based strippable coating.

[0079] Example 5

[0080] First, 0.8 g of a polyether-modified silicone-based stripping agent was fully dissolved in 50 g of methyl methacrylate, 50 g of butyl acrylate and 0.5 g of acrylic acid monomer, and then added to 55 g of a 6% aqueous solution of sodium dodecyl sulfate and OP-10 in an equal mass ratio, and high-speed shear emulsification was performed to obtain an emulsion.

[0081] Next, a three-necked flask with a condensation reflux and stirring device was placed in a 50°C water bath, 28 g of a 2.5% ammonium persulfate aqueous solution was poured into the three-necked flask, and the water bath was heated to 75°C.

[0082] Subsequently, the emulsion and 53 g of 4.5% ammonium persulfate aqueous solution were added dropwise into a three-necked flask within 3 hours. After the addition was completed, the water bath was heated to 80°C and kept warm for 4 hours. After natural cooling, the pH was adjusted to 6.5 with 2-amino-2-methyl-1-propanol. Filtration gave a polyacrylate emulsion in which the latex particles were in situ coated with a polyether-modified silicone-based release agent.

[0083] Then, take 100g of polyacrylate emulsion, add 46.2g of calcium carbonate stripping agent to the emulsion at a speed of 1500rpm and stir for 30min, reduce the speed to 1000rpm, add 1.15g of polymer non-silicon defoaming agent and 2.3g of phosphate composite organic zinc anti-flash rust agent and stir for 30min, adjust the pH to 8.5 with 2-amino-2-methyl-1-propanol, increase the speed to 1500rpm, add 1.55g of gas-phase silicon thickener and 1.55g of acrylic acid associative thickener and stir for 30min, add 1.15g of polymer non-silicon defoaming agent and stir for 5min, and discharge to obtain a water-based strippable coating.

[0084] Comparative Example 1

[0085] The polyether-modified silicone-based stripping agent was not added, and the remaining process was the same as that of Example 2.

[0086] Comparative Example 2

[0087] No polyether-modified silicone-based stripping agent was added to the film-forming agent, and only 0.212 g of the polyether-modified silicone-based stripping agent equivalent to that in Example 2 was added after the anti-flash rust agent was added, and the rest of the process was the same as that in Example 2. That is, compared with the above Examples 1-5, the polyether-modified silicone-based stripping agent was added in Comparative Example 2 by blending, rather than by in-situ addition inside the latex particles of the disclosed embodiments.

[0088] The coatings prepared in the above Examples 1 to 5 and Comparative Examples 1 and 2 were sprayed on a chlorinated rubber topcoat test plate and an A3 iron sheet. After drying, the peel strength of the coating was tested using a universal tensile machine. The test results are shown in Table 1:

[0089] Table 1

[0090]

[0091] By comparing Examples 1, 4, and 5, it can be seen that when the amount of the stripping agent is increased, the peel strength of the coating can be significantly reduced. By comparing Example 2 with Comparative Examples 1 and 2, it can be seen that the introduction of the stripping agent can significantly reduce the peel strength of the coating on the chlorinated rubber topcoat test plate, but compared with the blending introduction method, the in-situ introduction can more effectively reduce the peel strength of the coating on the chlorinated rubber topcoat test plate and the A3 iron plate.

[0092] It should be noted that although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0093] In addition, the above-mentioned figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present disclosure, and are not intended to be limiting. It is easy to understand that the processes shown in the above-mentioned figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0094] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing what is disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and embodiments are to be considered merely as exemplary, and the true scope and spirit of the present disclosure are indicated by the claims.

[0095] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A method for preparing a film-forming agent, characterized in that: include: A stripping agent, methyl methacrylate, butyl acrylate and acrylic acid are mixed to obtain a first mixed solution; wherein the stripping agent is a polyether-modified silicone substance; by weight, the stripping agent is 0.3 to 1 part; the methyl methacrylate is 45 to 55 parts, the butyl acrylate is 45 to 55 parts, and the acrylic acid is 0.3 to 1 part; Adding the first mixed solution to a target aqueous solution to obtain a second mixed solution, and subjecting the second mixed solution to a shear emulsification treatment to obtain an emulsion; wherein the target aqueous solution comprises sodium dodecyl sulfate and OP-10; adding a first aqueous solution of ammonium persulfate into a reactor; adding the emulsion and the second ammonium persulfate aqueous solution into the reactor in multiple times and over a predetermined period of time to obtain a third mixed solution; wherein the concentration of the second ammonium persulfate aqueous solution is greater than the concentration of the first ammonium persulfate aqueous solution; adjusting the pH of the third mixed solution to 6 to 7 to obtain a film-forming agent; Wherein, the film-forming agent is a polyacrylate emulsion, and the polyacrylate emulsion contains latex particles, and the interior of the latex particles is in-situ coated with the release aid.

2. The preparation method according to claim 1, characterized in that: By mass fraction, The target aqueous solution is 50 to 60 parts; Wherein, the mass ratio of the sodium dodecyl sulfate to the target aqueous solution is 5% to 8%, and the mass ratio of the OP-10 to the target aqueous solution is 5% to 8%.

3. The preparation method according to claim 1, characterized in that: Adding the first aqueous ammonium persulfate solution into the reactor comprises: 25 to 30 parts by mass of a first aqueous ammonium persulfate solution having a concentration of 2% to 3% are added to the reactor, and the temperature of the reactor is adjusted to 70° C. to 75° C.

4. The preparation method according to claim 1, characterized in that: The emulsion and the second aqueous ammonium persulfate solution are added to the reactor in multiple times and over a predetermined period of time to obtain a third mixed solution, comprising: The emulsion and 50 to 55 parts of a second aqueous ammonium persulfate solution having a concentration of 4% to 5% are added dropwise into the reactor in multiple portions over 1 to 4 hours, and after the addition is completed, the temperature of the reactor is adjusted to 80° C. to 85° C. and maintained for 3 to 4 hours.

5. A film-forming agent, characterized in that The film-forming agent is prepared by the method for preparing a film-forming agent according to any one of claims 1 to 4.

6. A method for preparing a water-based peelable coating, characterized in that: Using the film-forming agent of claim 5, the preparation method comprises: adding a stripping agent to the film-forming agent to obtain a first material; adding a first defoaming agent and a flash rust preventer to the first material to obtain a second material; adjusting the pH of the second material to 8 to 9, and adding a thickener to obtain a third material; A second defoamer is added to the third material to obtain a water-based strippable coating.

7. The preparation method according to claim 6, characterized in that: Adding a stripping agent to the film-forming agent to obtain a first material comprises: adding a stripping agent to the film-forming agent at a stirring speed of 1200 rpm to 1800 rpm, and stirring for 20 min to 40 min to obtain a first material; Wherein, the stripping agent is calcium carbonate, and the mass percentage of the stripping agent in the water-based strippable coating is 8.5% to 30%.

8. The preparation method according to claim 6, characterized in that: The first defoamer and the second defoamer are both polymer non-silicon defoamers, the first defoamer and the second defoamer have the same mass, and the sum of the mass of the first defoamer and the second defoamer in the water-based strippable coating is 0.5% to 1.5% by mass; The anti-flash rust agent is a phosphate composite organic zinc anti-flash rust agent, and the mass percentage of the anti-flash rust agent in the water-based strippable coating is 0.3% to 1.5%.

9. The preparation method according to claim 6, characterized in that: The thickener comprises an acrylic associative thickener and fumed silica, and the mass percentage of the thickener in the water-based strippable coating is 0.7% to 2.0%.

10. A water-based peelable coating, characterized in that: The water-based strippable coating is prepared by the preparation method of the water-based strippable coating according to any one of claims 6 to 9.

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