Water-based photocuring strippable film detergent as well as preparation method and application thereof

Abstract

The invention provides a water-based photocuring peelable film detergent as well as a preparation method and application thereof. The preparation method comprises the following steps: adding the coalescing agent, the active monomer and the filler into water, dissolving and stirring until the materials are uniformly mixed, dropwise adding the photoinitiator, and curing under ultraviolet light to form the peelable film. The preparation method comprises the following steps: taking polyvinyl alcohol and chitosan as film-forming substrates, adding acrylamide, acrylic acid and butyl acrylate as reactive diluents, initiating free radical polymerization through a photoinitiator under the action of cross-linking agents, namely epoxy chloropropane and trimethylolpropane triacrylate, so as to form a cross-linked network, and quickly forming a film. Titanium dioxide, carbon black and other fillers are added to improve the strength of the film body, and the ultraviolet curing rate can be improved by using the characteristic of carbon black for absorbing ultraviolet light. According to the strippable film coating, water is used as a solvent, an environment-friendly material polyvinyl alcohol is used as a matrix, a strippable film can be completely stripped on substrates with different surface roughness and surface energy, such as glass, stainless steel and cement, and meanwhile, the strippable film coating has a relatively high decontamination rate. The preparation method is simple in preparation, low in cost, environment-friendly, wide in application range, stable in performance and high in application value.

Description

Technical Field

[0001] The invention relates to the technical field of functional materials, and in particular to a water-based light-curable strippable film detergent and a preparation method and application thereof. Background Art

[0002] Strippable film decontaminants have been used for more than 70 years in various applications to remove surface contamination. This technology has been used to remove surface contamination from precision optical surfaces since the 1950s. With the continuous deepening of research, in addition to cleaning optical surfaces, strippable film decontaminants are increasingly used in other non-optical cleaning applications. Strippable coatings have been widely studied in wide-area surface decontamination applications due to their advantages such as simple construction, no damage to the substrate surface, and simple subsequent treatment. They are suitable for the protection and decontamination of difficult-to-access surfaces and can be applied to contaminated surfaces with high precision. These liquid film-forming materials are sprayed or brushed on the contaminated surface. During the curing process, the contaminants are attached mechanically and chemically. After curing, the cured film is removed to achieve the purpose of decontamination.

[0003] In recent years, the peelable film decontaminants used for decontamination generally include solvent-based and water-based polymer-based types. Currently, most of the solvent-based decontaminants are used, but solvent-based decontaminants use a large amount of organic solvents in the preparation process. These organic solvents evaporate during the subsequent curing process, causing environmental pollution and harming the health of the preparer and the user. With the increasing public awareness of environmental issues and the related demand for "green" products, the volatile organic compounds (VOCs) emissions generated by solvent-based peelable film decontaminants can be reduced or even avoided by using water-based decontaminants.

[0004] At present, the curing methods of peelable film detergents generally include heat curing, room temperature curing and light curing. Heat curing refers to heating the detergent coated on the surface to promote curing. This method has high requirements for curing equipment and limits the application range of peelable film detergents. Room temperature curing is a method of curing the detergent by placing it in a room temperature environment and letting the solvent or water in the detergent volatilize, but this method takes a long time (CN 115926515A, CN115368814A, CN 116656188 A, CN 111909558B). Therefore, at room temperature, the peelable film is prepared by ultraviolet light curing, and ultraviolet rays irradiate the photoinitiator to produce free radicals, which induce the polymerization of unsaturated bonds of monomers. This method not only has a high curing rate, low energy consumption, and simple preparation, forming energy-saving and environmentally friendly green coating products, but also has important significance for protecting the environment, ecological balance and sustainable development. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects of existing strippable film detergents such as volatile organic compound emissions, long curing time and high energy consumption, thereby providing a water-based light-curable strippable film detergent and its preparation method and application.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In the first aspect, the present invention provides an aqueous photocurable strippable film detergent, wherein the raw materials include, by weight: 20 to 40 parts of polyvinyl alcohol, 1 to 3 parts of chitosan, 600 to 650 parts of acrylamide, 400 to 550 parts of acrylic acid, 200 to 300 parts of butyl acrylate, 100 to 180 parts of trimethylolpropane triacrylate, 200 to 400 parts of epichlorohydrin, 60 to 65 parts of reinforcing filler, 40 to 55 parts of carbon black, and 0.5 to 1 part of photoinitiator.

[0008] Furthermore, the photoinitiator is one or more of TPO, 819DW, and 2959.

[0009] Furthermore, the reinforcing fillers are titanium dioxide and montmorillonite.

[0010] Furthermore, in the reinforcing filler, the mass ratio of titanium dioxide to montmorillonite is 1:3.

[0011] Furthermore, the relative molecular mass of the polyvinyl alcohol is preferably 27,000 to 67,000.

[0012] In a second aspect, the present invention provides a method for preparing an aqueous photocurable strippable film detergent, comprising the following steps:

[0013] Step 1, dissolving polyvinyl alcohol in water, heating and stirring at 80-100° C. until dissolved to obtain a polyvinyl alcohol solution;

[0014] Step 2, adding titanium dioxide, montmorillonite and chitosan to the polyvinyl alcohol solution obtained in step 1, reacting at 80-100° C. for 1-2 hours, stirring evenly, to obtain a mixed solution A;

[0015] Step 3, adding acrylamide, acrylic acid, butyl acrylate, and trimethylolpropane triacrylate to the mixed solution A obtained in step 2, and stirring evenly to obtain a mixed solution B;

[0016] Step 4, adding epichlorohydrin and carbon black to the mixed solution B obtained in step 3, stirring evenly to obtain a mixed solution C;

[0017] Step 5, adding a photoinitiator to the mixed solution C obtained in step 4, and stirring evenly to obtain an aqueous photocurable strippable film detergent.

[0018] Furthermore, in step 4, before adding epichlorohydrin and carbon black, sodium hydroxide solution is added to adjust the pH value of the mixed solution B to 9-11.

[0019] In a third aspect, the present invention provides an application of an aqueous photocurable strippable film cleaner, wherein the aqueous photocurable strippable film cleaner is coated on a substrate, left to stand under an ultraviolet lamp for 2 to 8 minutes, and the strippable film cleaner is peeled off after curing.

[0020] Furthermore, the substrate is glass, metal, cement, ceramic or plastic.

[0021] The technical solution of the present invention has the following advantages:

[0022] 1. The water-based photocurable strippable film detergent provided by the present invention adopts polyvinyl alcohol and chitosan as film-forming agents, and has the characteristics of abundant sources, sufficient reserves, and high safety in use; acrylamide, acrylic acid, and butyl acrylate are added as active diluents to provide a large number of cross-linking sites, and under the action of free radicals provided by the photoinitiator, the active monomers are cross-linked with each other; and under the action of cross-linking agents epichlorohydrin and trimethylolpropane triacrylate, the active monomers react with the cross-linking agent to form a cross-linked network and quickly form a film; fillers such as titanium dioxide and carbon black are added to improve the strength of the film body, and the ultraviolet light absorption characteristics of carbon black can be used to increase the ultraviolet curing rate, thereby quickly forming a strippable decontamination film.

[0023] 2. The synthesis process of the water-based light-curable strippable film detergent provided by the present invention uses water as a solvent instead of other solvents, which is low-cost and environmentally friendly.

[0024] 3. The water-based photocurable detergent of the present invention has good film-forming properties and can be applied to a variety of surfaces, such as metal, glass, ceramic, plastic and cement surfaces with uneven roughness. It has good strippability after UV curing and excellent decontamination ability. The decontamination rate on different surfaces exceeds 90%, which can meet the operational requirements of decontamination on different continuous surfaces.

[0025] 4. The present invention is simple to prepare, low in cost, stable in performance, and environmentally friendly, and has wide application value in actual production and life. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1The present invention is a peeling effect diagram of a water-based photocurable film cleaner provided by an embodiment of the present invention applied on the surface of glass, cement, and stainless steel to form a peelable film. DETAILED DESCRIPTION

[0028] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0029] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the art can be used. The raw materials or instruments used are all conventional products that can be obtained commercially, including but not limited to the raw materials or instruments used in the examples of this application.

[0030] In the following, in conjunction with the accompanying drawings, a water-based photocurable film decontaminant, a preparation method and an application thereof provided by an embodiment of the present invention will be described in detail.

[0031] Example 1

[0032] The present embodiment provides a water-based photocurable strippable film detergent, which comprises, by weight, 20 parts of polyvinyl alcohol, 2 parts of chitosan, 610 parts of acrylamide, 500 parts of acrylic acid, 230 parts of butyl acrylate, 100 parts of trimethylolpropane triacrylate, 320 parts of epichlorohydrin, 60 parts of reinforcing fillers (titanium dioxide and montmorillonite), 43 parts of carbon black, and 0.5 parts of photoinitiator 819DW.

[0033] In this embodiment, the preparation method of the aqueous light-curable strippable film detergent comprises the following steps:

[0034] Step (1), dissolving polyvinyl alcohol in water, heating and stirring at 90° C. until the polyvinyl alcohol solution is uniform;

[0035] Step (2), adding titanium dioxide, montmorillonite and chitosan to the polyvinyl alcohol solution obtained in step 1, reacting at 90° C. for 1 h, and stirring evenly to obtain a mixed solution A;

[0036] Step (3), adding acrylamide, acrylic acid, butyl acrylate, and trimethylolpropane triacrylate to the mixed solution A obtained in step 2, and stirring evenly to obtain a mixed solution B;

[0037] Step (4), adding epichlorohydrin and carbon black to the mixed solution B obtained in step 3, stirring evenly, to obtain a mixed solution C;

[0038] Step (5), adding photoinitiator 819DW to the mixed solution C obtained in step 4, stirring evenly, to obtain a water-based photocurable strippable film detergent.

[0039] In this embodiment, the water-based light-curable peelable film detergent is coated on the surface of glass, stainless steel, and cement substrates, and left to stand under ultraviolet light for 5 minutes respectively. After curing, the peelable film is peeled off.

[0040] Example 2

[0041] The present embodiment provides a water-based photocurable strippable film detergent, which comprises, by weight, 20 parts of polyvinyl alcohol, 2 parts of chitosan, 610 parts of acrylamide, 500 parts of acrylic acid, 230 parts of butyl acrylate, 170 parts of trimethylolpropane triacrylate, 300 parts of epichlorohydrin, 60 parts of reinforcing fillers (titanium dioxide and montmorillonite), 43 parts of carbon black, and 29590.5 parts of photoinitiator.

[0042] In this embodiment, the preparation method and application of the aqueous photocurable strippable film detergent can refer to Example 1.

[0043] Example 3

[0044] The present embodiment provides a water-based light-curable strippable film detergent, which comprises, by weight, 20 parts of polyvinyl alcohol, 2 parts of chitosan, 610 parts of acrylamide, 500 parts of acrylic acid, 230 parts of butyl acrylate, 120 parts of trimethylolpropane triacrylate, 380 parts of epichlorohydrin, 60 parts of reinforcing fillers (titanium dioxide and montmorillonite), 43 parts of carbon black, and 0.5 parts of photoinitiator TPO.

[0045] In this embodiment, the preparation method and application of the aqueous photocurable strippable film detergent can refer to Example 1.

[0046] Example 4

[0047] The present embodiment provides a water-based light-curable strippable film detergent, which comprises, by weight, 25 parts of polyvinyl alcohol, 1 part of chitosan, 620 parts of acrylamide, 500 parts of acrylic acid, 250 parts of butyl acrylate, 120 parts of trimethylolpropane triacrylate, 300 parts of epichlorohydrin, 60 parts of reinforcing fillers (titanium dioxide and montmorillonite), 43 parts of carbon black, and 0.8 parts of photoinitiator 819DW.

[0048] In this embodiment, the preparation method and application of the water-based photocurable peelable film cleaner can refer to Example 1, except that the water-based photocurable peelable film cleaner is coated on the surface of glass, stainless steel, and cement substrates, respectively, and left under ultraviolet light for 2 minutes, and the peelable film is peeled off after curing.

[0049] Example 5

[0050] The present embodiment provides a water-based light-curable strippable film detergent, which includes, by weight, 22 parts of polyvinyl alcohol, 1 part of chitosan, 630 parts of acrylamide, 480 parts of acrylic acid, 250 parts of butyl acrylate, 160 parts of trimethylolpropane triacrylate, 280 parts of epichlorohydrin, 60 parts of reinforcing fillers (titanium dioxide and montmorillonite), 43 parts of carbon black, and 0.4 parts of photoinitiator 819DW.

[0051] In this embodiment, the preparation method and application of the water-based photocurable peelable film cleaner can refer to Example 1, except that the water-based photocurable peelable film cleaner is coated on the surface of glass, stainless steel, and cement substrates, respectively, and left under ultraviolet light for 8 minutes, and the peelable film is peeled off after curing.

[0052] Experimental Example 1

[0053] The water-based photocurable strippable film detergent prepared in Example 1 of the present invention was tested for strippability and film-forming properties.

[0054] Preparation before the test:

[0055] (1) Using a glass sheet, a 304 stainless steel sheet, and a cement sheet with a size of 5 cm×25 cm as substrates, the water-based photocurable peelable film detergent prepared in Example 1 was applied to the surfaces of the three substrates by manual brushing, and the coating thickness was 1.0 mm;

[0056] (2) The three substrates were exposed to ultraviolet light and cured for 5 minutes to obtain a water-based photocurable peelable film.

[0057] Peelability test:

[0058] Take three samples, peel off the peelable film from the substrate, and observe the peeling effect of the film on different substrate surfaces. The peeling rate is calculated as follows:

[0059] Peeling rate = one-time peeling area / coating area.

[0060] Film forming rate experiment:

[0061] Take three samples to observe the curing film-forming effect of the water-based light-curable strippable film cleaner under ultraviolet light. The film-forming rate is calculated as follows:

[0062] Film formation rate = film formation area / coating area.

[0063] The test results are shown in Table 1.

[0064] Table 1 Film formation rate and strippability test results of the water-based photocurable strippable film detergent prepared in Example 1 coated on different substrate surfaces

[0065] Base Film forming rate (%) Peelability (%) Glass 100 100 304 Stainless Steel 1 00 100 Cement sheet 1 00 100

[0066] As shown in Table 1, the water-based photocurable strippable film detergent prepared in Example 1 was coated on three different substrates, namely glass, 304 stainless steel and cement, and exhibited good film-forming properties and strippability.

[0067] See also Figure 1 As shown in the figure, the water-based light-curable peelable film detergent prepared in Example 1 is coated on three different substrates: glass, 304 stainless steel and cement. After UV curing, a peelable film is formed, and the peelable film can be completely peeled off from the substrate.

[0068] Experimental Example 2

[0069] The decontamination performance of the aqueous photocurable strippable film decontaminant prepared in Example 1 of the present invention was tested.

[0070] Preparation before the test:

[0071] (1) A glass sheet, a 3 cm × 3 cm stainless steel sheet, or a cement sheet was used as the substrate;

[0072] (2) Cesium chloride is dissolved in water to obtain a cesium chloride solution, the solution is applied to the surface of a substrate, and the contaminated substrate is obtained after the solution is dried.

[0073] (3) The water-based photocurable peelable film detergent prepared in Example 1 is brushed onto the surface of the contaminated substrate, and after curing, a water-based photocurable peelable film is obtained.

[0074] Decontamination rate:

[0075] After the peelable film is peeled off, the surface contamination level of the substrate after decontamination is measured, and the decontamination rate is calculated according to the decontamination formula.

[0076]

[0077] Where DE is the decontamination rate, n 1 is the amount of cesium chloride in the solution obtained after decontamination, n 0 It is the amount of cesium chloride substance in the solution prepared before contamination.

[0078] The test results are shown in Table 2.

[0079] Table 2 Decontamination rate test results of the water-based photocurable strippable film decontaminant prepared in Example 1

[0080] Base Decontamination rate (%) 304 Stainless Steel 99.75 Glass 99.69 Cement sheet 92.67

[0081] As shown in Table 2, the water-based photocurable strippable film cleaner prepared in Example 1 was coated on three different substrates, namely glass, 304 stainless steel and cement, and a strippable film was formed after UV curing. The strippable film had a decontamination rate of greater than 99% on the stainless steel surface and the glass surface, and a decontamination rate of 92.7% on the rough cement surface, which had a relatively high decontamination rate.

[0082] Experimental Example 3

[0083] The mechanical properties of the aqueous photocurable strippable film detergents prepared in Examples 1 to 5 of the present invention were tested.

[0084] Preparation before the test:

[0085] The aqueous photocurable film decontaminant prepared in Examples 1 to 5 was coated on a standard sample mold and UV-cured to obtain a peelable film.

[0086] Mechanical properties:

[0087] The tensile strength and elongation at break of the peelable film were tested using an Instron 68TM-50,000-watt mechanical testing machine.

[0088] The test results are shown in Table 3.

[0089] Table 3 Performance test results of the peelable film formed by the aqueous photocurable peelable film detergent prepared in Examples 1 to 5

[0090]

[0091]

[0092] As shown in Table 3, the tensile strength of the peelable film formed by the aqueous photocurable peelable film detergent prepared in Examples 1 to 5 can reach up to 1.64 MPa. It can be seen that the aqueous photocurable peelable film provided by the present invention has good mechanical properties and meets the mechanical property requirements of the peelable film.

[0093] In summary, the water-based photocurable strippable film detergent provided by the present invention uses polyvinyl alcohol and chitosan as film-forming agents, and has the characteristics of abundant sources, sufficient reserves, high safety in use, etc. Active monomers such as acrylamide are used to provide a large number of cross-linking sites. Under the action of free radicals provided by a photoinitiator, the active monomers are cross-linked with each other, and under the action of a trimethylolpropane triacrylate cross-linking agent, the active monomers react with the cross-linking agent to form a cross-linked network. Carbon black is used because it has a high absorption rate in the ultraviolet light range, which can increase the ultraviolet light curing rate of the detergent, thereby quickly forming a strippable decontamination film.

[0094] The present invention has carried out the stripping property and film-forming property test of the water-based light-curable strippable film detergent, as shown in Table 1, Figure 1As shown in Table 2, the film-forming rate on the glass, 304 stainless steel and rough cement substrate surfaces reached 100%, and the strippability rate reached 100%, showing good film-forming and strippability. Decontamination performance tests were also conducted. As shown in Table 2, the decontamination rate on the rough cement surface reached 92.7%, and the decontamination rate on the glass and 304 stainless steel contaminated surfaces was greater than 99%, showing high decontamination performance. Mechanical properties tests were conducted on the strippable films formed by water-based light-curable strippable film decontaminants with different component ratios. As shown in Table 3, the tensile strength can reach up to 1.64MPa.

[0095] The water-based light-curable strippable film decontaminant of the present invention has good film-forming property and can be applied to various surfaces, such as metal, glass, ceramic, plastic and cement surface with uneven roughness. It has good strippability after UV curing and excellent decontamination ability, and can meet the requirements of decontamination operation on different continuous surfaces.

[0096] The synthesis process of the water-based photocurable strippable film cleaner provided by the invention uses water as a solvent instead of other solvents, is low-cost, green and environmentally friendly, and has simple preparation and stable performance, and has wide application value in actual production and life.

[0097] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A water-based photocurable strippable film detergent, characterized in that: Calculated by weight, the raw materials include: 20-40 parts of polyvinyl alcohol, 1-3 parts of chitosan, 600-650 parts of acrylamide, 400-550 parts of acrylic acid, 200-300 parts of butyl acrylate, 100-180 parts of trimethylolpropane triacrylate, 200-400 parts of epichlorohydrin, 60-65 parts of reinforcing filler, 40-55 parts of carbon black, and 0.5-1 part of photoinitiator.

2. The aqueous photocurable peelable film detergent according to claim 1, characterized in that: The photoinitiator is one or more of TPO, 819DW and 2959.

3. The aqueous photocurable peelable film detergent according to claim 1, characterized in that: The reinforcing fillers are titanium dioxide and montmorillonite.

4. The aqueous photocurable peelable film detergent according to claim 1, characterized in that: In the reinforcing filler, the mass ratio of titanium dioxide to montmorillonite is 1:

3.

5. The aqueous photocurable peelable film detergent according to claim 1, characterized in that: The relative molecular mass of the polyvinyl alcohol is 27000-67000.

6. The method for preparing the aqueous photocurable peelable film detergent according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1, dissolving polyvinyl alcohol in water, heating and stirring at 80-100° C. until dissolved to obtain a polyvinyl alcohol solution; Step 2, adding titanium dioxide, montmorillonite and chitosan to the polyvinyl alcohol solution obtained in step 1, reacting at 80-100° C. for 1-2 hours, stirring evenly, to obtain a mixed solution A; Step 3, adding acrylamide, acrylic acid, butyl acrylate, and trimethylolpropane triacrylate to the mixed solution A obtained in step 2, and stirring evenly to obtain a mixed solution B; Step 4, adding epichlorohydrin and carbon black to the mixed solution B obtained in step 3, stirring evenly to obtain a mixed solution C; Step 5, adding a photoinitiator to the mixed solution C obtained in step 4, stirring evenly, to obtain the water-based photocurable peelable film detergent.

7. The method for preparing the water-based photocurable peelable film detergent according to claim 6, characterized in that: In step 4, before adding epichlorohydrin and carbon black, sodium hydroxide solution is added to adjust the pH value of the mixed solution B to 9-11.

8. Use of the aqueous photocurable peelable film detergent according to claims 1 to 7, characterized in that: The water-based light-curable strippable film detergent is coated on a substrate, left to stand under an ultraviolet lamp for 2 to 8 minutes, and the strippable film detergent is peeled off after curing.

9. The use of the aqueous photocurable peelable film detergent according to claim 8, characterized in that: The substrate is glass, metal, cement, ceramic or plastic.

Images