Rosin modified acrylate coating

Abstract

The invention relates to the technical field of functional coatings, and provides a rosin modified acrylate coating. The acrylate coating is a modified acrylate copolymer emulsion, and a modified acrylate copolymer is a random copolymer of a compound X, methyl methacrylate, butyl acrylate, methacrylic acid and hexafluorobutyl methacrylate. The structure of the compound X simultaneously contains an acrylate structure, a rosin ester structure and a halamine structure. According to the method disclosed by the invention, not only is the modified acrylate coating with good waterproof and oil-proof performance and antibacterial performance obtained, but also the rosin part and the halamine part are connected to the side group of the polyacrylate, and the coating does not contain free rosin compounds or halamine compounds, so that the rosin part and the halamine part can be prevented from being migrated and separated out from the coating; further, the water-proof, oil-proof and antibacterial properties of the coating are prevented from being reduced.

Description

Technical Field

[0001] The invention relates to the technical field of functional coatings and provides a rosin-modified acrylate coating. Background Art

[0002] For environmental protection, traditional disposable plastic cups have been gradually replaced by disposable paper cups. The barrier film layer on the surface of paper cups is mostly polyethylene coating, which has the disadvantages of being non-degradable and non-repulpable, making it more difficult to recycle paper cups. The use of environmentally friendly coating materials can overcome this disadvantage. Environmentally friendly coating materials include water-based polyurethane coatings, water-based acrylic coatings, polylactic acid coatings, cellulose coatings, protein active coatings, etc.

[0003] Water-based acrylic ester has the advantages of uniform coating, good anti-fouling, good wear resistance and high reslurry rate, but its waterproof and oil-proof performance needs to be improved when used as paper cup coating. The introduction of fluorinated acrylate as a comonomer can significantly improve the waterproof and oil-proof performance of water-based acrylic ester coating, but due to the strong polarity of the fluorocarbon chain, it will reduce the stability of the molecule. Therefore, the amount of fluorinated acrylate added should be controlled at a low level.

[0004] Studies have shown that modifying acrylic emulsion with rosin can improve the waterproof and oil-proof properties of the coating. One is to use blending. Due to the large difference in particle size between rosin emulsion particles and polymer emulsion particles, it is easy to precipitate and stratify. The other is to use copolymerization. Although there are polymerizable conjugated double bonds in the rosin structure, the double bonds are located on the tricyclic structure, which has large steric hindrance and is not easy to participate in polymerization. The unpolymerized free rosin is easy to migrate and precipitate from the coating.

[0005] In addition, paper cups are usually used to hold water, drinks or food, so giving them antibacterial properties is of great significance for food safety. Halamine compounds have broad-spectrum and long-lasting antibacterial properties, but because they are small molecules, adding them directly to water-based acrylic paints is similar to free rosin, and they are also easy to migrate and precipitate under certain conditions. Summary of the invention

[0006] In order to prepare an acrylic coating with good waterproof and oil-proof properties and antibacterial properties, and to overcome the defects that rosin is not easy to participate in copolymerization and small molecule antibacterial substances are easy to migrate and precipitate, the present invention provides a rosin-modified acrylic coating and a preparation method thereof.

[0007] To achieve the above purpose, the specific technical solution of the present invention is as follows:

[0008] The invention provides a rosin-modified acrylic ester coating, wherein the acrylic ester coating is a modified acrylic ester copolymer emulsion.

[0009] The modified acrylic ester copolymer is a random copolymer, and its monomer units include compound X monomer units, methyl methacrylate monomer units, butyl acrylate monomer units, methacrylic acid monomer units, and hexafluorobutyl methacrylate monomer units. That is, the modified acrylic ester copolymer is a random copolymer of compound X, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate.

[0010] Wherein, the structural formula of the compound X is as shown in the attached Figure 1 shown.

[0011] Preferably, in the structure of the modified acrylic ester copolymer, the molar ratio of the compound X monomer unit, the methyl methacrylate monomer unit, the butyl acrylate monomer unit, the methacrylic acid monomer unit, and the hexafluorobutyl methacrylate monomer unit is 0.2-0.3: 0.4-0.6: 0.8-1: 0.6-0.8: 0.05-0.1.

[0012] The present invention further provides a preparation process of the modified acrylate copolymer emulsion, which is specifically:

[0013] S1, adding isocyanuric acid and triethylamine to ethylene glycol monomethyl ether, stirring and heating under reflux, introducing a certain amount of ethylene oxide when the temperature reaches 100-110°C, raising the temperature to 115-120°C and refluxing for 12-15h, cooling in an ice-water bath for crystallization, filtering with suction, recrystallizing with methanol, filtering with suction, and drying to obtain compound A;

[0014] S2, adding compound A and triethylamine into methanol, slowly adding a methanol solution of di-tert-butyl dicarbonate dropwise, stirring at room temperature for 8-12 hours, cooling in an ice-water bath for crystallization, filtering with suction, and drying to obtain compound B;

[0015] S3, adding compound B, pyridine and triethylamine to toluene, heating to 50°C, then adding rosin acid chloride, stirring and reacting for 3-4 hours, then adding acryloyl chloride, continuing the reaction for 3-4 hours, cooling in an ice-water bath for crystallization, filtering, washing with saturated sodium chloride solution and deionized water in turn, and drying to obtain compound C;

[0016] S4, adding compound C to a saturated solution of dry hydrogen chloride in tetrahydrofuran, stirring and reacting at room temperature for 8-10 hours, filtering with suction, rinsing with icy ether, and drying to obtain compound D;

[0017] S5, premixing compound D, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to form a monomer mixture, adding 1 / 3 of the monomer mixture, 1 / 2 of potassium persulfate, 1 / 2 of sodium bisulfite, and sodium dodecyl sulfate into deionized water, stirring and heating to 65-70° C. and reflux reaction for 2-3 hours, then adding the remaining monomer mixture, potassium persulfate, and sodium bisulfite, heating to 80-85° C. and continuing the reaction for 4-5 hours, and cooling to obtain a copolymer emulsion;

[0018] S6, cooling the copolymer emulsion to 10-15°C, adjusting the pH value to 8-9, adding sodium hypochlorite solution, and stirring for 20-30 minutes.

[0019] In the above step S1, ethylene oxide is reacted with isocyanuric acid to connect 2-hydroxyethyl groups to the two N groups in the isocyanuric acid structure to obtain di(2-hydroxyethyl)isocyanurate, i.e., compound A, whose structural formula is shown in the attached figure. Figure 2 To ensure that disubstituted isocyanurate is obtained, the molar ratio of isocyanuric acid to ethylene oxide should be controlled to be 1:2. Preferably, in S1, the amount ratio of isocyanuric acid, ethylene glycol monomethyl ether, triethylamine, and ethylene oxide is 1 mol: 250-300 mL: 0.02-0.03 mol: 2 mol.

[0020] In the above step S2, di-tert-butyl dicarbonate is used to protect the remaining -NH- on the isocyanuric acid structure to ensure that only the hydroxyl group on the 2-hydroxyethyl group reacts in the subsequent reaction. After protection, compound B is obtained, and its structural formula is as shown in the attached figure. Figure 3 Preferably, in S2, the usage ratio of compound A, di-tert-butyl dicarbonate, triethylamine and methanol is 1 mol: 1-1.1 mol: 1-1.1 mol: 400-600 mL.

[0021] The above step S3 is a process in which two hydroxyl groups on compound B react with acyl chloride groups. First, one hydroxyl group reacts with rosin acyl chloride to form rosin ester, and then the other hydroxyl group reacts with acryloyl chloride to form acrylate to obtain compound C, whose structural formula is shown in the attached figure. Figure 4 As shown. To ensure that the compound after the reaction contains both rosin ester and acrylate structures, the molar ratio of compound B, rosin acyl chloride and acryloyl chloride should be controlled to be 1:1:1, and acryloyl chloride should be added after the rosin acyl chloride is fully reacted. Preferably, in S3, the amount ratio of compound B, rosin acyl chloride, acryloyl chloride, pyridine, triethylamine and toluene is 1 mol: 1 mol: 1 mol: 0.2-0.3 mol: 2-2.2 mol: 300-500 mL.

[0022] The above step S4 is a deprotection process corresponding to step S2. The deprotection is performed using hydrogen chloride to obtain the corresponding hydrochloride, i.e., compound D, whose structural formula is shown in the attached figure. Figure 5 As shown. Preferably, in S4, the molar ratio of compound C to hydrogen chloride is 1:2.5-3. It can be seen that after the preparation process of S1-S4, in the structure of isocyanuric acid, one N is connected to a group containing a rosin ester structure, one N is connected to a group containing an acrylate structure (which can participate in the polymerization reaction through C=C), and one N forms a hydrochloride.

[0023] The above step S5 is a process in which compound D is copolymerized with other acrylic monomers through its C=C to obtain a modified acrylic copolymer emulsion composed of monomer units of compound D, methyl methacrylate monomer units, butyl acrylate monomer units, methacrylic acid monomer units, and hexafluorobutyl methacrylate monomer units. Preferably, in S5, the amount ratio of compound D, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate, and deionized water is 0.2-0.3 mol: 0.4-0.6 mol: 0.8-1 mol: 0.6-0.8 mol: 0.05-0.1 mol: 0.02-0.04 mol: 0.04-0.06 mol: 0.3-0.5 mol: 400-600 mL.

[0024] In the above step S6, the -NH-·HCl on the monomer unit of compound D in the copolymer is first converted into -NH- by adjusting the pH, and then -NH- is converted into -NCl- by sodium hypochlorite, so that the monomer unit of compound D in the copolymer is converted into the monomer unit of compound X. Preferably, in S6, the concentration of the sodium hypochlorite solution is 10-15wt%, and the molar ratio of sodium hypochlorite to the monomer unit of compound D in the copolymer is 1.05-1.1:1. It can be seen that the random copolymer of compound X, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate provided by the present invention is not directly obtained by copolymerizing compound X with other acrylic monomers, but is first obtained by copolymerizing compound D with other acrylic monomers and then converting -NH-·HCl into -NCl-.

[0025] As mentioned above, on the one hand, rosin can improve the waterproof and oil-proof properties of acrylic coatings, but the conjugated double bonds in the rosin structure are located in the tricyclic structure, which is not easy to copolymerize with acrylic monomers, and the unpolymerized free rosin is easy to migrate and precipitate from the coating; on the other hand, common halamine antibacterial compounds are small molecules. If they are directly added to water-based acrylic coatings, they are also easy to migrate and precipitate from the coating under certain conditions. The gradual migration and precipitation of free rosin or halamine compounds will cause the coating's waterproof and oil-proof properties and antibacterial properties to gradually decrease.

[0026] The present invention creatively utilizes the structural characteristics of isocyanuric acid, which has three reactive -NH-, and utilizes them in different ways:

[0027] For the first -NH-, -CH2CH2OH is first connected to N through reaction with ethylene oxide, and then the hydroxyl group is used to react with rosin acid chloride to form rosin ester, thereby connecting the rosin ester structure to isocyanuric acid. For the second -NH-, similarly, -CH2CH2OH is first connected to N through reaction with ethylene oxide, and then the hydroxyl group is used to react with acryloyl chloride to form acrylate, thereby connecting the acrylate structure to isocyanuric acid, thereby giving the compound the ability to copolymerize with other acrylic monomers through C=C. After the rosin ester structure and the acrylate structure are connected to isocyanuric acid, the acrylate structure is copolymerized with methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to obtain an emulsion coating. The method of the present invention introduces a rosin ester structure into the side group of the acrylate copolymer, which is used in combination with the fluorine-containing monomer hexafluorobutyl methacrylate to further improve the waterproof and oil-proof performance of the acrylate coating. In addition, the rosin does not need to rely on the conjugated double bonds on its own tricyclic structure to participate in polymerization, but relies on C=C of the acrylate structure to participate in polymerization, thereby significantly reducing the difficulty of polymerization, thereby preventing the existence of free rosin in the emulsion.

[0028] For the third -NH-, it undergoes BOC protection, deprotection, and halogenation, and finally becomes a halogenamine structure (N-Cl). It is well known that halogenamine compounds are organic antibacterial agents with broad-spectrum and long-acting antibacterial functions, do not produce toxic and side effects on the human body, and are environmentally friendly. Although rosin has certain antibacterial functions, its antibacterial effect is limited. By introducing the halogenamine structure through the method of the present invention, the antibacterial effect of the coating can be significantly improved. Moreover, the present invention does not directly add small molecule halogenamine compounds to the coating, but introduces the halogenamine structure through the third -NH- of isocyanuric acid. After copolymerization, the halogenamine structure is located on the side group of the copolymer and becomes a part of the polymer structure, thereby preventing the presence of free halogenamine compounds in the emulsion.

[0029] As can be seen from the above, the present invention provides a rosin-modified acrylate coating and a preparation method thereof, which has the following beneficial effects:

[0030] The present invention modifies three -NH- of isocyanuric acid, wherein: one is connected to a group containing an acrylate structure, giving it the ability to copolymerize with other acrylic monomers and becoming a part of the acrylate copolymer structure; one is connected to a group containing a rosin ester structure to further improve the waterproof and oil-proof performance of the acrylate coating; and one is converted into a halamine structure to significantly improve the antibacterial effect of the acrylate coating. Through the method of the present invention, not only a modified acrylate coating with good waterproof and oil-proof performance and antibacterial performance is obtained, but also the rosin part and the halamine part are both connected to the side group of the polyacrylate, and there is no free rosin compound or halamine compound in the coating, which can prevent the two from migrating and precipitating from the coating during storage or use, thereby preventing the reduction of the waterproof and oil-proof performance and antibacterial performance of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is the structural formula of compound X;

[0032] Figure 2 is the structural formula of compound A;

[0033] Figure 3 is the structural formula of compound B;

[0034] Figure 4 is the structural formula of compound C;

[0035] Figure 5 is the structural formula of compound D. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below by specific embodiments, but this should not be construed as limiting the scope of the present invention to the following examples. Without departing from the above-mentioned method concept of the present invention, various substitutions or changes made according to common technical knowledge and customary means in the art should be included in the scope of the present invention. The raw materials involved in the following examples and comparative examples are all conventional commercial products.

[0037] Example 1

[0038] S1, adding isocyanuric acid and triethylamine to ethylene glycol monomethyl ether, stirring and heating under reflux, introducing a certain amount of ethylene oxide when the temperature reaches 105°C, heating to 115°C and reflux for 15h, cooling in an ice-water bath for crystallization, filtering with suction, recrystallizing with methanol, filtering with suction, and drying to obtain compound A;

[0039] S2, compound A and triethylamine are added to methanol, and a methanol solution of di-tert-butyl dicarbonate is slowly added dropwise, and the mixture is stirred at room temperature for 12 hours, cooled in an ice-water bath for crystallization, filtered, and dried to obtain compound B;

[0040] S3, compound B, pyridine and triethylamine were added to toluene, heated to 50°C, then rosin acid chloride was added, stirred and reacted for 3.5 hours, then acryloyl chloride was added, reacted for 3.5 hours, cooled in an ice-water bath for crystallization, filtered, washed with saturated sodium chloride solution and deionized water in turn, and dried to obtain compound C;

[0041] S4, adding compound C to a saturated solution of dry hydrogen chloride in tetrahydrofuran, stirring the mixture for reaction at room temperature for 10 h, filtering the mixture with suction, rinsing the mixture with icy ether, and drying the mixture to obtain compound D;

[0042] S5, premixing compound D, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to form a monomer mixture, adding 1 / 3 of the monomer mixture, 1 / 2 of potassium persulfate, 1 / 2 of sodium bisulfite, and sodium dodecyl sulfate into deionized water, stirring and heating to 65° C. and reflux reaction for 3 h, then adding the remaining monomer mixture, potassium persulfate, and sodium bisulfite, heating to 85° C. and continuing the reaction for 4 h, and cooling to obtain a copolymer emulsion;

[0043] S6, cooling the copolymer emulsion to 12°C, adjusting the pH value to 8, adding sodium hypochlorite solution, and stirring for 20 minutes.

[0044] In S1, the usage ratio of isocyanuric acid, ethylene glycol monomethyl ether, triethylamine and ethylene oxide is 1 mol:300 mL:0.05 mol:2 mol.

[0045] In S2, the usage ratio of compound A, di-tert-butyl dicarbonate, triethylamine and methanol is 1 mol: 1 mol: 1 mol: 400 mL.

[0046] In S3, the usage ratio of compound B, rosin acid chloride, acryloyl chloride, pyridine, triethylamine and toluene is 1 mol: 1 mol: 1 mol: 0.25 mol: 2.1 mol: 400 mL.

[0047] In S4, the molar ratio of compound C to hydrogen chloride is 1:2.5.

[0048] In S5, the dosage ratio of compound D, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.2 mol: 0.5 mol: 0.9 mol: 0.7 mol: 0.075 mol: 0.03 mol: 0.05 mol: 0.4 mol: 500 mL.

[0049] In S6, the concentration of the sodium hypochlorite solution is 13 wt %, and the molar ratio of sodium hypochlorite to the monomer unit of compound D in the copolymer is 1.1:1.

[0050] Example 2

[0051] S1, adding isocyanuric acid and triethylamine to ethylene glycol monomethyl ether, stirring and heating under reflux, introducing a certain amount of ethylene oxide when the temperature reaches 105°C, heating to 120°C and refluxing for 12h, cooling in an ice-water bath for crystallization, filtering with suction, recrystallizing with methanol, filtering with suction, and drying to obtain compound A;

[0052] S2, compound A and triethylamine are added to methanol, and a methanol solution of di-tert-butyl dicarbonate is slowly added dropwise, and the mixture is stirred at room temperature for 8 hours, cooled in an ice-water bath for crystallization, filtered, and dried to obtain compound B;

[0053] S3, compound B, pyridine and triethylamine are added to toluene, heated to 50°C, then rosin acid chloride is added, stirred and reacted for 3 hours, then acryloyl chloride is added, reacted for 3 hours, cooled in an ice-water bath for crystallization, filtered, washed with saturated sodium chloride solution and deionized water in turn, and dried to obtain compound C;

[0054] S4, adding compound C to a saturated solution of dry hydrogen chloride in tetrahydrofuran, stirring the mixture for reaction at room temperature for 8 h, filtering the mixture with suction, rinsing the mixture with icy ether, and drying the mixture to obtain compound D;

[0055] S5, premixing compound D, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to form a monomer mixture, adding 1 / 3 of the monomer mixture, 1 / 2 of potassium persulfate, 1 / 2 of sodium bisulfite, and sodium dodecyl sulfate into deionized water, stirring and heating to 68° C. and reflux reaction for 2.5 hours, then adding the remaining monomer mixture, potassium persulfate, and sodium bisulfite, heating to 82° C. and continuing the reaction for 4.5 hours, and cooling to obtain a copolymer emulsion;

[0056] S6, cooling the copolymer emulsion to 15°C, adjusting the pH value to 8, adding sodium hypochlorite solution, and stirring for 25 minutes.

[0057] In S1, the usage ratio of isocyanuric acid, ethylene glycol monomethyl ether, triethylamine and ethylene oxide is 1 mol:250 mL:0.025 mol:2 mol.

[0058] In S2, the usage ratio of compound A, di-tert-butyl dicarbonate, triethylamine and methanol is 1 mol: 1.1 mol: 1.1 mol: 600 mL.

[0059] In S3, the usage ratio of compound B, rosin acid chloride, acryloyl chloride, pyridine, triethylamine and toluene is 1 mol: 1 mol: 1 mol: 0.3 mol: 2.2 mol: 350 mL.

[0060] In S4, the molar ratio of compound C to hydrogen chloride is 1:3.

[0061] In S5, the dosage ratio of compound D, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.25 mol: 0.5 mol: 0.9 mol: 0.7 mol: 0.075 mol: 0.03 mol: 0.05 mol: 0.4 mol: 500 mL.

[0062] In S6, the concentration of the sodium hypochlorite solution is 13 wt %, and the molar ratio of sodium hypochlorite to the monomer unit of compound D in the copolymer is 1.1:1.

[0063] Example 3

[0064] S1, adding isocyanuric acid and triethylamine to ethylene glycol monomethyl ether, stirring and heating under reflux, introducing a certain amount of ethylene oxide when the temperature reaches 105°C, heating to 118°C and reflux for 13h, cooling in an ice-water bath for crystallization, filtering with suction, recrystallizing with methanol, filtering with suction, and drying to obtain compound A;

[0065] S2, compound A and triethylamine are added to methanol, and a methanol solution of di-tert-butyl dicarbonate is slowly added dropwise, and the mixture is stirred at room temperature for 10 hours, cooled in an ice-water bath for crystallization, filtered, and dried to obtain compound B;

[0066] S3, compound B, pyridine and triethylamine are added to toluene, heated to 50°C, then rosin acid chloride is added, stirred and reacted for 4 hours, then acryloyl chloride is added, reacted for 4 hours, cooled in an ice-water bath for crystallization, filtered, washed with saturated sodium chloride solution and deionized water in turn, and dried to obtain compound C;

[0067] S4, adding compound C to a saturated solution of dry hydrogen chloride in tetrahydrofuran, stirring the mixture for reaction at room temperature for 9 hours, filtering the mixture with suction, rinsing the mixture with icy ether, and drying the mixture to obtain compound D;

[0068] S5, premixing compound D, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to form a monomer mixture, adding 1 / 3 of the monomer mixture, 1 / 2 of potassium persulfate, 1 / 2 of sodium bisulfite, and sodium dodecyl sulfate into deionized water, stirring and heating to 70° C. and reflux reaction for 2 h, then adding the remaining monomer mixture, potassium persulfate, and sodium bisulfite, heating to 80° C. and continuing the reaction for 5 h, and cooling to obtain a copolymer emulsion;

[0069] S6, cooling the copolymer emulsion to 10°C, adjusting the pH value to 8, adding sodium hypochlorite solution, and stirring for 30 minutes.

[0070] In S1, the usage ratio of isocyanuric acid, ethylene glycol monomethyl ether, triethylamine and ethylene oxide is 1 mol:270 mL:0.025 mol:2 mol.

[0071] In S2, the usage ratio of compound A, di-tert-butyl dicarbonate, triethylamine and methanol is 1 mol: 1.05 mol: 1.05 mol: 500 mL.

[0072] In S3, the usage ratio of compound B, rosin acid chloride, acryloyl chloride, pyridine, triethylamine and toluene is 1 mol: 1 mol: 1 mol: 0.2 mol: 2 mol: 450 mL.

[0073] In S4, the molar ratio of compound C to hydrogen chloride is 1:2.3.

[0074] In S5, the dosage ratio of compound D, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.3 mol: 0.5 mol: 0.9 mol: 0.7 mol: 0.075 mol: 0.03 mol: 0.05 mol: 0.4 mol: 600 mL.

[0075] In S6, the concentration of the sodium hypochlorite solution is 13 wt %, and the molar ratio of sodium hypochlorite to the monomer unit of compound D in the copolymer is 1.05:1.

[0076] Comparative Example 1

[0077] Compared with Example 3, compound D was not prepared, and methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate were used to directly prepare the acrylic coating. The preparation process is as follows:

[0078] Methyl methacrylate, butyl acrylate, methacrylic acid and hexafluorobutyl methacrylate are premixed to form a monomer mixture, 1 / 3 of the monomer mixture, 1 / 2 potassium persulfate, 1 / 2 sodium bisulfite and sodium dodecyl sulfate are added into deionized water, stirred and heated to 70°C for reflux reaction for 2 hours, then the remaining monomer mixture, potassium persulfate and sodium bisulfite are added, the temperature is raised to 80°C and the reaction is continued for 5 hours, and then cooled to obtain a copolymer emulsion.

[0079] The dosage ratio of methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.5 mol: 0.9 mol: 0.7 mol: 0.075 mol: 0.03 mol: 0.05 mol: 0.4 mol: 600 mL.

[0080] Comparative Example 2

[0081] Compared with Example 3, compound D was not prepared, but rosin and chloroisocyanuric acid were directly added to the preparation system. The preparation process is:

[0082] Rosin, chloroisocyanuric acid, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate are premixed into a mixture, 1 / 3 of the mixture, 1 / 2 potassium persulfate, 1 / 2 sodium bisulfite, and sodium dodecyl sulfate are added into deionized water, stirred and heated to 70°C for reflux reaction for 2 hours, then the remaining mixture, potassium persulfate, and sodium bisulfite are added, the temperature is raised to 80°C for reaction for 5 hours, and cooled to obtain a copolymer emulsion.

[0083] The dosage ratio of rosin, chloroisocyanuric acid, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.3 mol: 0.3 mol: 0.5 mol: 0.9 mol: 0.7 mol: 0.075 mol: 0.03 mol: 0.05 mol: 0.4 mol: 600 mL.

[0084] The test selected paper cup base paper (180g / ㎡) produced by Shanghai Kaining Paper Industry. Before the test, an air knife was used to apply the above coatings on the base paper. Two coatings were applied on one side (primer coating + top coating), with a single coating of 2.5g / ㎡ and a total coating of 5g / ㎡. After vacuum drying, the paper was used as the test sample.

[0085] (1) The sample papers of Examples 1-3 were folded into a small box without a lid, with the coated surface facing inward, and freshly boiled hot water was added. The box was left to stand for 30 minutes to observe whether there was water seepage. The results showed that no water seepage occurred in the sample papers of Examples 1-3, indicating that the coating formed by the acrylic paint prepared in the present invention had good waterproof performance.

[0086] (2) The sample papers of Examples 1-3 were folded into a small box without a lid, with the coated surface facing inward, and edible oil was added. The box was left to stand for 24 hours to observe whether there was oil seepage. The results showed that the sample papers of Examples 1-3 had no oil seepage, indicating that the coating formed by the acrylic paint prepared in the present invention had good oil-proof performance.

[0087] (3) Water contact angle test: OCA40 contact angle measuring instrument was used. The test temperature was (25±2)°C and the relative humidity was (65±2%). For the samples of Example 3 and Comparative Example 1, the contact angle values ​​of water on the samples were measured at 5 points and the average value was taken.

[0088] (4) Oil contact angle test: Using the test instrument and method of (3), the contact angle values ​​of diiodomethane on the sample papers of Example 3 and Comparative Example 1 were measured respectively. Five points were measured and the average value was taken.

[0089] The results show that the water contact angles of the sample papers of Example 3 and Comparative Example 1 are 125.5° and 114.3°, respectively, and the oil contact angles are 114.7° and 101.4°, respectively. This is because the rosin ester structure is introduced into the side group of the copolymer of Example 3, which, when used in combination with the fluorine-containing monomer, can further improve the water and oil repellency of the acrylic coating.

[0090] (5) Antibacterial test: The strains of Escherichia coli and Staphylococcus aureus were activated and cultured in a bacterial culture medium with constant temperature shaking for 24 hours to obtain a bacterial solution. Among them, Escherichia coli was cultured in LB medium, with 10 g / L tryptone, 5 g / L yeast extract powder, and 10 g / L sodium chloride, and the pH value was adjusted to 7.8; Staphylococcus aureus was cultured in a high-salt medium, with 10 g / L tryptone, 5 g / L beef extract, and 75 g / L sodium chloride, and the pH value was adjusted to 7.4. 0.5 mL of bacterial solution was dropped on the surface of the sample paper of Examples 1-3 and Comparative Example 1 and the blank sample paper, respectively, and a layer of medical PE film was covered. After 30 minutes, the PE film was removed, and 20 mL of phosphate buffer was used for elution, and then the plate was coated and counted. The antibacterial rate was calculated according to the following formula: Antibacterial rate = (C0-C) × 100% / C0, where C0 is the number of viable bacteria in the blank sample paper and C is the number of viable bacteria in the test sample paper.

[0091] The results show that the antibacterial rates of the samples of Example 1, Example 2, Example 3 and Comparative Example 1 against Escherichia coli are 97.51%, 98.73%, 99.32% and 16.55%, respectively, and the antibacterial rates against Staphylococcus aureus are 98.26%, 99.35%, 99.87% and 21.92%, respectively. This is because the halamine structure and rosin ester structure are introduced into the side groups of the copolymers of the embodiments, the halamine has good antibacterial properties, and the rosin also has a certain antibacterial effect, thereby giving the acrylic coating good antibacterial properties.

[0092] (6) The sample paper of Example 3 and Comparative Example 2 was divided into two parts, one of which was directly tested for water contact angle, oil contact angle, Escherichia coli antibacterial rate, and Staphylococcus aureus antibacterial rate according to the methods of (3), (4), and (5), and the other was immersed in a mixture of water, ethanol, and ether in a volume ratio of 1:1:1, stirred at a speed of 2000 rpm, and ultrasonically oscillated (ultrasonic frequency of 50 kHz and power of 500 W). After 72 hours, the paper was taken out, rinsed with deionized water, and vacuum dried. The water contact angle, oil contact angle, Escherichia coli antibacterial rate, and Staphylococcus aureus antibacterial rate were tested again according to the methods of (3), (4), and (5). The reduction rates of water contact angle, oil contact angle, Escherichia coli antibacterial rate, and Staphylococcus aureus antibacterial rate were calculated using the test data before and after treatment. Reduction rate = (data before treatment - data after treatment) × 100% / data before treatment.

[0093] The results show that the water contact angle reduction rates of the samples of Example 3 and Comparative Example 2 after treatment are 0.08% and 2.38% respectively, the oil contact angle reduction rates are 0.1% and 3.12% respectively, the Escherichia coli antibacterial rate reduction rates are 0.07% and 4.85% respectively, and the Staphylococcus aureus antibacterial rate reduction rates are 0.06% and 4.31% respectively. This is because: there are free rosin and halamine compounds in the coating prepared in Comparative Example 2. After high-speed stirring and ultrasonic treatment, the two migrate and precipitate, resulting in a decrease in the waterproof and oil-proof performance and antibacterial performance of the acrylic ester coating. The preparation method of the present invention connects the rosin part and the halamine part to the side group of the polyacrylate, becoming a part of the polymer structure, and is not prone to migration and precipitation. Therefore, the waterproof and oil-proof performance and antibacterial performance of the coating after treatment do not change significantly.

Claims

1. A rosin-modified acrylic coating, wherein the acrylic coating is a modified acrylic copolymer emulsion, wherein the modified acrylic copolymer is a random copolymer of compound X, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate, characterized in that: The structural formula of the compound X is 2. The acrylic paint according to claim 1, characterized in that: In the structure of the modified acrylic ester copolymer, the molar ratio of the compound X monomer unit, the methyl methacrylate monomer unit, the butyl acrylate monomer unit, the methacrylic acid monomer unit, and the hexafluorobutyl methacrylate monomer unit is 0.2-0.3: 0.4-0.6: 0.8-1: 0.6-0.8: 0.05-0.

1.

3. The acrylic coating according to any one of claims 1 or 2, characterized in that: The preparation process of the modified acrylate copolymer emulsion is: S1, adding isocyanuric acid and triethylamine to ethylene glycol monomethyl ether, stirring and heating under reflux, introducing a certain amount of ethylene oxide when the temperature reaches 100-110°C, heating to 115-120°C and reflux reaction for 12-15h, cooling in an ice-water bath for crystallization, filtering with suction, recrystallizing with methanol, filtering with suction, and drying to obtain compound A; the molar ratio of isocyanuric acid to ethylene oxide is 1:2; S2, adding compound A and triethylamine into methanol, slowly adding a methanol solution of di-tert-butyl dicarbonate dropwise, stirring at room temperature for 8-12 hours, cooling in an ice-water bath for crystallization, filtering with suction, and drying to obtain compound B; S3, compound B, pyridine and triethylamine are added to toluene, heated to 50°C, then rosin acid chloride is added, stirred to react for 3-4 hours, then acryloyl chloride is added, the reaction is continued for 3-4 hours, cooled in an ice-water bath for crystallization, filtered, washed with saturated sodium chloride solution and deionized water in turn, and dried to obtain compound C; the molar ratio of compound B, rosin acid chloride and acryloyl chloride is 1:1:1; S4, adding compound C to a saturated solution of dry hydrogen chloride in tetrahydrofuran, stirring and reacting at room temperature for 8-10 hours, filtering with suction, rinsing with icy ether, and drying to obtain compound D; S5, premixing compound D, methyl methacrylate, butyl acrylate, methacrylic acid, and hexafluorobutyl methacrylate to form a monomer mixture, adding 1 / 3 of the monomer mixture, 1 / 2 of potassium persulfate, 1 / 2 of sodium bisulfite, and sodium dodecyl sulfate into deionized water, stirring and heating to 65-70° C. and reflux reaction for 2-3 hours, then adding the remaining monomer mixture, potassium persulfate, and sodium bisulfite, heating to 80-85° C. and continuing the reaction for 4-5 hours, and cooling to obtain a copolymer emulsion; S6, cooling the copolymer emulsion to 10-15°C, adjusting the pH value to 8-9, adding sodium hypochlorite solution, and stirring for 20-30 minutes.

4. The acrylic paint according to claim 3, characterized in that: In S1, the usage ratio of isocyanuric acid, ethylene glycol monomethyl ether, triethylamine and ethylene oxide is 1 mol: 250-300 mL: 0.02-0.03 mol: 2 mol.

5. The acrylic paint according to claim 3, characterized in that: In S2, the usage ratio of compound A, di-tert-butyl dicarbonate, triethylamine and methanol is 1 mol: 1-1.1 mol: 1-1.1 mol: 400-600 mL.

6. The acrylic paint according to claim 3, characterized in that: In S3, the usage ratio of compound B, rosin acid chloride, acryloyl chloride, pyridine, triethylamine and toluene is 1 mol: 1 mol: 1 mol: 0.2-0.3 mol: 2-2.2 mol: 300-500 mL.

7. The acrylic paint according to claim 3, characterized in that: In S4, the molar ratio of compound C to hydrogen chloride is 1:2.5-3.

8. The acrylic paint according to claim 3, characterized in that: In S5, the dosage ratio of compound D, methyl methacrylate, butyl acrylate, methacrylic acid, hexafluorobutyl methacrylate, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate and deionized water is 0.2-0.3 mol: 0.4-0.6 mol: 0.8-1 mol: 0.6-0.8 mol: 0.05-0.1 mol: 0.02-0.04 mol: 0.04-0.06 mol: 0.3-0.5 mol: 400-600 mL.

9. The acrylic paint according to claim 3, characterized in that: In S6, the concentration of the sodium hypochlorite solution is 10-15 wt %, and the molar ratio of the sodium hypochlorite to the monomer unit of the compound D in the copolymer is 1.05-1.1:1.

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