A kind of gingerol acrylate and its application in preparing light-curing coating

Abstract

The present invention provides gingerol acrylate and its application in preparing a photocurable coating, belonging to the technical field of coatings. The present invention obtains gingerol acrylate monomer by reacting gingerol with acryloyl chloride in a n-hexane solution, and the gingerol acrylate monomer cooperates with each component of 6-functionality polyurethane acrylate, 2-functionality polyurethane acrylate, active diluent, photoinitiator, wetting agent, leveling agent, and defoamer to synergistically act, so that the prepared coating has good antibacterial effect, reduces the use of antibacterial agents, and is energy-saving and environmentally friendly; and the preparation method is simple and suitable for industrial large-scale production.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to gingerol acrylate and application thereof in preparing light-curing coatings. Background Art

[0002] Photocuring coatings use high-energy ultraviolet light as the curing energy source. The photoinitiator in the coating absorbs ultraviolet light to produce free radicals or cations, which trigger polymerization and cross-linking reactions of oligomers and active diluents to form a network structure of coatings. It has the characteristics of energy saving, fast curing speed, low VOC emissions, and high production efficiency. With the continuous improvement of photocuring coatings, it is not only used in wood, metal, plastic, paper, leather and other products, but also in optical fibers, printed circuit boards, electronic component packaging and other materials.

[0003] At present, in order for a coating to have an antibacterial function, it is usually necessary to add an antibacterial agent or a bactericide, most of which are artificially synthesized agents and do not have long-term effectiveness. Frequent use of coatings containing antibacterial agents or bactericides may also cause bacteria to develop drug resistance, and may easily have negative effects on human health. It may also destroy the balance of other microorganisms in the environment, thereby causing serious pollution, which is not conducive to the development of photocuring coatings. Summary of the invention

[0004] In view of the defects of the prior art, the present invention obtains gingerol acrylate monomer by reacting gingerol with acryloyl chloride in a n-hexane solution. The gingerol acrylate monomer can be used with components such as 6-functional polyurethane acrylate and 2-functional polyurethane acrylate to prepare a photocurable coating with good long-term antibacterial effect.

[0005] In order to achieve the above purpose, the present invention solves the technical problem by adopting the following technical solutions:

[0006] On the one hand, the present invention provides a photocurable coating, which includes, by mass percentage, 3% to 20% of gingerol acrylate monomer, 20% to 45% of 6-functionality polyurethane acrylate, 3% to 15% of 2-functionality polyurethane acrylate, 3% to 15% of active diluent, 1% to 10% of photoinitiator, 0.5% to 5% of wetting agent, 1% to 5% of leveling agent, and 0.1% to 2% of defoaming agent.

[0007] In some of the embodiments, the composition includes, by mass percentage, 5% to 15% gingerol acrylate monomer, 25% to 40% 6-functionality polyurethane acrylate, 5% to 10% 2-functionality polyurethane acrylate, 5% to 10% active diluent, 3% to 8% photoinitiator, 1% to 3% wetting agent, 2% to 4% leveling agent, and 0.5% to 1% defoaming agent.

[0008] In some of the embodiments, the composition includes, by mass percentage, 10% gingerol acrylate monomer, 30% 6-functional polyurethane acrylate, 8% 2-functional polyurethane acrylate, 8% active diluent, 5% photoinitiator, 2% wetting agent, 3% leveling agent, and 0.8% defoaming agent.

[0009] In some of the embodiments, the preparation of the gingerol acrylate monomer includes: dissolving gingerol in n-hexane, then adding a n-hexane solution of acryloyl chloride to react at 2-6° C., and filtering, washing, and drying the reaction product to obtain the gingerol acrylate monomer.

[0010] In some embodiments, the reactive diluent is any one of dipropylene glycol diacrylate, tripropylene glycol diacrylate, methyl methacrylate, ethyl acrylate, and caprolactone acrylate.

[0011] In some embodiments, the photoinitiator is any one of 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and α-hydroxyalkyl phenone.

[0012] In some embodiments, the wetting agent is a polyether siloxane copolymer.

[0013] In some embodiments, the leveling agent is BYK-354, BYK-333, BYK-310, BYK-450 or ANK-1033.

[0014] In some embodiments, the defoaming agent is a silicone defoaming agent.

[0015] On the other hand, the present invention provides a method for preparing the photocurable coating, wherein gingerol acrylate monomer, 6-functionality polyurethane acrylate, 2-functionality polyurethane acrylate, reactive diluent, photoinitiator, wetting agent, leveling agent and defoaming agent are mixed and stirred at 600-1000 rpm for 20-40 minutes to obtain the photocurable coating.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The invention uses gingerol as the basis to modify and synthesize acrylic monomers, and cooperates with components including 6-functionality polyurethane acrylate, 2-functionality polyurethane acrylate, active diluent, photoinitiator, wetting agent, leveling agent and defoamer to achieve synergistic effect. The prepared coating has good long-term antibacterial effect, reduces the use of antibacterial agents, and is energy-saving and environmentally friendly. The preparation method is simple, and the raw materials except the gingerol acrylate monomer are easily obtained, so the coating is suitable for industrial large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is the structural formula of gingerol acrylate monomer. DETAILED DESCRIPTION

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In the present invention, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0022] In the present invention, the test methods used are conventional methods unless otherwise specified; the materials, reagents, etc. used are reagents and materials that can be obtained from commercial channels unless otherwise specified.

[0023] The viscosity of 6-functionality polyurethane acrylate is 1000-2000cps, 25℃, and it is a slightly yellow liquid.

[0024] The viscosity of 2-functional polyurethane acrylate is 5000~15000cps, 25℃, transparent liquid.

[0025] In the present invention, the preparation method of gingerol acrylate comprises the following steps:

[0026] 50 g of gingerol was dissolved in 300 mL of n-hexane, and then a n-hexane solution of acryloyl chloride (prepared by adding 5 g of acryloyl chloride to 15 mL of n-hexane) was uniformly added in an ice-water bath at 2-6° C. for 30 min to carry out the reaction. The reaction time was 15 h. After the reaction, the product was filtered through a Buchner funnel, washed with water and isobutanol for 2-3 times, and dried at low temperature to obtain gingerol acrylate monomer.

[0027] Example 1

[0028] A photocurable coating comprises, by mass percentage, 10% of gingerol acrylate monomer, 30% of 6-functionality polyurethane acrylate, 8% of 2-functionality polyurethane acrylate, 8% of active diluent, 5% of photoinitiator, 2% of wetting agent, 3% of leveling agent and 0.8% of defoaming agent.

[0029] In this embodiment, the active diluent is methyl methacrylate; the photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone; the wetting agent is polyether siloxane copolymer Digo 280; the leveling agent is BYK-333; and the defoaming agent is BYK-035.

[0030] According to the above formula, gingerol acrylate monomer, 6-functional polyurethane acrylate, 2-functional polyurethane acrylate, reactive diluent, photoinitiator, wetting agent, leveling agent and defoaming agent were mixed at 800 rpm and stirred for 30 minutes to prepare a light-curing coating.

[0031] Example 2

[0032] A photocurable coating comprises, by mass percentage, 5% of gingerol acrylate monomer, 40% of 6-functionality polyurethane acrylate, 5% of 2-functionality polyurethane acrylate, 10% of active diluent, 3% of photoinitiator, 1% of wetting agent, 4% of leveling agent and 0.5% of defoaming agent.

[0033] In this embodiment, the active diluent is ethyl acrylate; the photoinitiator is α-hydroxyalkyl phenone; the wetting agent is polyether siloxane copolymer Digo 280; the leveling agent is Digo 450; and the defoaming agent is BYK-066N.

[0034] According to the above formula, gingerol acrylate monomer, 6-functional polyurethane acrylate, 2-functional polyurethane acrylate, reactive diluent, photoinitiator, wetting agent, leveling agent and defoaming agent were mixed at 1000 rpm and stirred for 20 minutes to prepare a light-curing coating.

[0035] Example 3

[0036] A photocurable coating comprises, by mass percentage, 15% of gingerol acrylate monomer, 25% of 6-functionality polyurethane acrylate, 10% of 2-functionality polyurethane acrylate, 5% of active diluent, 8% of photoinitiator, 3% of wetting agent, 2% of leveling agent and 1% of defoaming agent.

[0037] In this embodiment, the active diluent is dipropylene glycol diacrylate; the photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone; the wetting agent is polyether siloxane copolymer Digo 280; the leveling agent is BYK-333; and the defoaming agent is BYK-025.

[0038] According to the above formula, gingerol acrylate monomer, 6-functional polyurethane acrylate, 2-functional polyurethane acrylate, reactive diluent, photoinitiator, wetting agent, leveling agent and defoaming agent were mixed at 600 rpm and stirred for 40 minutes to prepare a light-curing coating.

[0039] Comparative Example 1

[0040] The difference between Comparative Example 1 and Example 1 is that the formulation of the photocurable coating is different, and the other aspects are the same.

[0041] A photocurable coating comprises, by mass percentage, 20% of gingerol acrylate monomer, 20% of 6-functionality polyurethane acrylate, 3% of 2-functionality polyurethane acrylate, 15% of active diluent, 1% of photoinitiator, 5% of wetting agent, 5% of leveling agent and 0.2% of defoaming agent.

[0042] Comparative Example 2

[0043] The difference between Comparative Example 2 and Example 1 is that the formulation of the photocurable coating is different, and the other aspects are the same.

[0044] A photocurable coating comprises, by mass percentage, 3% of gingerol acrylate monomer, 45% of 6-functionality polyurethane acrylate, 15% of 2-functionality polyurethane acrylate, 4% of active diluent, 9% of photoinitiator, 0.5% of wetting agent, 1% of leveling agent and 2% of defoaming agent.

[0045] Comparative Example 3

[0046] The difference between Comparative Example 3 and Example 1 is that capsaicin is used to modify the synthetic acrylate monomer, and the other aspects are the same.

[0047] The method for preparing the acrylic acid ester monomer comprises the following steps:

[0048] Capsaicin is dissolved in n-hexane, and then a n-hexane solution of acryloyl chloride is added at 2-6° C. to react, and the reaction product is separated and purified to obtain an acrylate monomer.

[0049] Comparative Example 4

[0050] Comparative Example 4 is different from Example 1 in that gingerol acrylate monomer is not added, and the other aspects are the same.

[0051] Comparative Example 5

[0052] Comparative Example 5 is different from the example in that hexafunctional polyurethane acrylate is not added, and the other aspects are the same.

[0053] Comparative Example 6

[0054] The difference between Comparative Example 6 and Example 1 is that no difunctional polyurethane acrylate is added, and the other aspects are the same.

[0055] Test Example 1

[0056] The photocurable coatings prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were coated on plastic substrates respectively, and then the substrates were illuminated by a high pressure mercury lamp (with an incident light intensity of 40 mW / cm 2 ) to obtain the sample to be tested. Test indicators:

[0057] 1. Hardness test: GB6739-86 "Coating hardness pencil test method"

[0058] 2. Adhesion test: GB_T 9286-2021 "Scratch test for paints and varnishes"

[0059] 3. Antibacterial test

[0060] According to GB / T 21866-2008 "Determination of Antibacterial Properties and Antibacterial Effects of Antibacterial Coatings (Paint Films)", the antibacterial effect of photocurable coatings was tested. An experimental group (the photocurable coatings prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were coated on a plastic substrate) and a blank control group (plastic substrate) were set up, and the experimental group and the blank control group sterilized by ultraviolet light were placed in 2 mL of the Escherichia coli suspension to be inoculated and cultured at 37°C for 3 hours. Take out the sample coating and wash the surface of the sample with a sterile PBS buffer solution, then place the sample in a sterile PBS solution and use ultrasonic treatment to disperse the bacteria on the sample into the PBS solution. Use a pipette to take 100 μL and evenly apply it on the solid culture medium. After incubation in a constant temperature biochemical incubator at 37°C for 24 hours, calculate the number of colonies and calculate the antibacterial rate. The antibacterial rate calculation formula is as follows:

[0061]

[0062] Wherein, B is the average number of bacteria recovered from the blank control sample after 24 hours (cfu / piece), and C is the average number of bacteria recovered from the light-cured coating after 24 hours (cfu / piece).

[0063] The test results are shown in Table 1 below:

[0064] Table 1 Light-curing coating performance test table

[0065] Group hardness Adhesion Antibacterial rate (%) Example 1 2H Level 0 87.5 Example 2 2H Level 0 84.6 Example 3 2H Level 0 85.8 Comparative Example 1 2H Level 1 73.2 Comparative Example 2 2H Level 0 78.5 Comparative Example 3 H Level 1 80.7 Comparative Example 4 F Level 2 44.2 Comparative Example 5 B Level 2 69.4 Comparative Example 6 HB Level 2 71.2

[0066] It can be seen from Table 1 that Examples 1 to 3 all have good hardness and adhesion, and the antibacterial rate is higher than 80%. In particular, by comparing Example 1 with Comparative Examples 3 and 4, it can be seen that the coating made from capsaicin acrylate monomer also has good antibacterial properties, but its adhesion and hardness are lower than those of the coating made from gingerol acrylate monomer. This is because gingerol can not only effectively inhibit bacteria or fungi, but also help to improve the mechanical strength of the coating.

[0067] Further comparison of Example 1 with Comparative Examples 5 and 6 shows that the hardness and adhesion of Comparative Examples 5 and 6 are lower than those of Example 1. This is because the hexafunctional polyurethane acrylate has more functional groups and can provide more cross-linking points. When used with the difunctional polyurethane acrylate with better fluidity, it helps to improve the mechanical properties of the material.

[0068] In summary, the gingerol acrylate monomer, 6-functionality polyurethane acrylate, 2-functionality polyurethane acrylate, reactive diluent, photoinitiator, wetting agent, leveling agent and defoaming agent of the present invention cooperate with each other within a certain range and work synergistically. The prepared light-cured coating not only has a high antibacterial rate, but also has good mechanical properties, which is beneficial to reducing the growth of bacteria or fungi on the coating surface, thereby extending the practical life of the product, while also reducing the excessive use of chemical substances and reducing the impact on the environment.

[0069] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A photocurable coating, characterized in that: According to the mass percentage, it includes 3% to 20% of gingerol acrylate monomer, 20% to 45% of 6-functional polyurethane acrylate, 3% to 15% of 2-functional polyurethane acrylate, 3% to 15% of active diluent, 1% to 10% of photoinitiator, 0.5% to 5% of wetting agent, 1% to 5% of leveling agent, and 0.1% to 2% of defoaming agent; Gingerol acrylate monomer is obtained by reacting gingerol with acryloyl chloride in n-hexane solution.

2. The photocurable coating according to claim 1, characterized in that: In terms of mass percentage, it includes 5%-15% of gingerol acrylate monomer, 25%-40% of 6-functionality polyurethane acrylate, 5%-10% of 2-functionality polyurethane acrylate, 5%-10% of active diluent, 3%-8% of photoinitiator, 1%-3% of wetting agent, 2%-4% of leveling agent and 0.5%-1% of defoaming agent.

3. The photocurable coating according to claim 1, characterized in that: In terms of mass percentage, it includes 10% gingerol acrylate monomer, 30% 6-functional polyurethane acrylate, 8% 2-functional polyurethane acrylate, 8% active diluent, 5% photoinitiator, 2% wetting agent, 3% leveling agent and 0.8% defoaming agent.

4. The photocurable coating according to claim 1, characterized in that: The preparation of the gingerol acrylate monomer comprises: dissolving gingerol in n-hexane, then adding a n-hexane solution of acryloyl chloride at 2-6° C. to react, and filtering, washing and drying the reaction product to obtain the gingerol acrylate monomer.

5. The photocurable coating according to claim 1, characterized in that: The active diluent is any one of dipropylene glycol diacrylate, tripropylene glycol diacrylate, methyl methacrylate, ethyl acrylate and caprolactone acrylate.

6. The photocurable coating according to claim 1, characterized in that: The photoinitiator is any one of 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and α-hydroxyalkyl phenone.

7. The photocurable coating according to claim 1, characterized in that: The wetting agent is a polyether siloxane copolymer.

8. The photocurable coating according to claim 1, characterized in that: The leveling agent is BYK-354, BYK-333, BYK-310, Digo 450 or ANK-1033.

9. The photocurable coating according to claim 1, characterized in that: The defoamer is an organosilicon defoamer.

10. The method for preparing a photocurable coating according to any one of claims 1 to 9, characterized in that: The gingerol acrylate monomer, 6-functional polyurethane acrylate, 2-functional polyurethane acrylate, active diluent, photoinitiator, wetting agent, leveling agent and defoamer are mixed at 600-1000 rpm and stirred for 20-40 minutes to prepare a light-curing coating.

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