Plastic matte ultraviolet curing coating and preparation method thereof

Abstract

The invention relates to the field of ultraviolet curing coatings, in particular to a plastic matte ultraviolet curing coating and a preparation method thereof.The plastic matte ultraviolet curing coating is prepared from, by weight, 30-40 parts of acrylic resin, 15-30 parts of bifunctional monomers, 30-45 parts of trifunctional monomers, 5-10 parts of modifier, 1-5 parts of active amine, 3-6 parts of initiator and 1-3 parts of auxiliaries; the structural formula of the modifier is as follows: # imgabs0 #. A coating film formed after the coating prepared by the invention is subjected to ultraviolet curing has good mechanical properties and strong adhesive force with a plastic matrix.

Description

Technical Field

[0001] The invention relates to the field of ultraviolet curing coatings, in particular to a plastic matte ultraviolet curing coating and a preparation method thereof. Background Art

[0002] Compared with traditional coatings, UV-curing coatings do not contain any organic solvents or volatile components, have a solid content of nearly 100%, and cause less pollution to the environment. At the same time, they have the characteristics of low curing energy consumption, high film-forming efficiency, good chemical stability, and wide applicability. They are widely used in the surface treatment of plastic structural parts such as home appliances, automobiles, mobile phones, PCs, medical equipment, and lighting appliances. They are a modern coating that is efficient, energy-saving, and environmentally friendly.

[0003] However, UV-curing coatings have insufficient wettability and weak penetration on plastic substrates, which affects their adhesion, which limits their application to a certain extent. Summary of the invention

[0004] Purpose of the invention: In view of the above technical problems, the present invention proposes a plastic matte UV-curing coating and a preparation method thereof.

[0005] The technical solutions adopted are as follows: A plastic matte UV-curing coating, comprising the following components in parts by weight: 30-40 parts of acrylic resin, 15-30 parts of bifunctional monomer, 30-45 parts of trifunctional monomer, 5-10 parts of modifier, 1-5 parts of active amine, 3-6 parts of initiator, and 1-3 parts of auxiliary agent; The acrylic resin is composed of aromatic polyurethane modified acrylate, epoxy modified acrylate and polyester modified acrylate; The mass ratio of the aromatic polyurethane modified acrylate, epoxy modified acrylate and polyester modified acrylate is 1-3:1-3:1-3; The structural formula of the modifier is as follows: .

[0006] Furthermore, the preparation method of the modifier is as follows: ; S1: 4,4',4''-methylenetriphenol and 2,2-dihydroxymethylpropionic acid undergo esterification to obtain an intermediate product; ; S2: The intermediate product undergoes a condensation reaction with epichlorohydrin to obtain the modifier.

[0007] Furthermore, the bifunctional monomer is one or a combination of two or more of ethylene glycol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol methacrylate, tripropylene glycol methacrylate, tetraethylene glycol methacrylate, polyethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, propoxylated neopentyl glycol diacrylate, 1,6-ethylene glycol dimethyl diacrylate, phthalic acid dimethacrylate, phthalic acid monoethylene glycol dimethacrylate, ethoxylated bisphenol A dimethacrylate, and hydroxypivalic acid neopentyl glycol monoester dimethacrylate.

[0008] Furthermore, the trifunctional monomer is one or a combination of two or more of trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, glycerol trihydroxypropyl ether triacrylate, and pentaerythritol triacrylate.

[0009] Furthermore, the active amine consists of triethanolamine and isophoronediamine.

[0010] Furthermore, the mass ratio of triethanolamine to isophoronediamine is 1-5:1-5.

[0011] Further, the initiator is one or a combination of two or more of 1-hydroxycyclohexyl benzophenone, p-phenyl benzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone, 2-benzyl-2-methylamino-1-(4-morpholinophenyl)-1-butanone, 2-(4-methylbenzyl)-2-methylamino-1-(4-morpholinophenyl)-1-butanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 4,4'-bis(diethylamino)benzophenone, and isopropylthioxanthone.

[0012] Furthermore, the auxiliary agent includes one or a combination of two or more of a dispersant, a leveling agent, a defoaming agent, and a matting powder.

[0013] The present invention also provides a method for preparing a plastic matte UV-curable coating: Under light-proof conditions, firstly mix the acrylic resin, bifunctional monomer, trifunctional monomer and modifier evenly, then add the active amine, initiator and auxiliary agent and stir thoroughly.

[0014] Beneficial effects of the present invention: The present invention provides a plastic matte ultraviolet light-curing coating. The aromatic polyurethane-modified acrylate has good flexibility, strong adhesion and strength after film formation, and good weather resistance and chemical resistance. After the epoxy-modified acrylate is added, the coating can be quickly cured, and the gloss and wear resistance after film formation are improved. The polyester-modified acrylate has low viscosity, high wettability, good leveling property, and fast curing speed. After being added, the adhesion of the coating can be improved. The three are combined to jointly improve the mechanical properties of the light-curing coating after film formation and the adhesion to the plastic substrate. The modifier has an aromatic structure and multiple epoxy groups. The epoxy group can The active amine composed of triethanolamine and isophoronediamine can inhibit the oxygen inhibition effect of ultraviolet-cured coatings and catalyze the crosslinking of epoxy groups to improve the density of the coating film. The coating film prepared by the present invention has good mechanical properties after ultraviolet curing and has strong adhesion to the plastic substrate. DETAILED DESCRIPTION

[0015] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially. The techniques not mentioned in the present invention are all referenced to the prior art. Unless otherwise specified, the following examples and comparative examples are parallel experiments, using the same processing steps and parameters.

[0016] Aromatic polyurethane modified acrylate: model R2205, purchased from Green Union (Jining) Chemical Technology Co., Ltd.; Epoxy modified acrylate: model UV-51600, purchased from Jining Fangyu Chemical Co., Ltd.; Polyester modified acrylate: model R3201, purchased from Green Union (Jining) Chemical Technology Co., Ltd.; Ethylene glycol dimethacrylate: purchased from Jiangsu Bosite Chemical Technology Co., Ltd.; Trimethylolpropane trimethacrylate: purchased from Jiangsu Bosite Chemical Technology Co., Ltd.; Modifier: Homemade; Triethanolamine: Merck; Isophorone diamine: Merck; 1-Hydroxycyclohexylbenzophenone: purchased from Wuhan Kemik Biopharmaceutical Technology Co., Ltd.; BYK-110 dispersant: purchased from Shanghai Kaiyin Chemical Co., Ltd.; BYK-380 leveling agent: purchased from Shanghai Kaiyin Chemical Co., Ltd.; BYK-1790 defoamer: purchased from Shanghai Kaiyin Chemical Co., Ltd.; RAD-2105 matte powder: Shenzhen Yoshida Chemical Co., Ltd.

[0017] Embodiment 1: A plastic matte UV-curing coating, comprising the following components in parts by weight: 12 parts of aromatic polyurethane modified acrylate, 12 parts of epoxy modified acrylate, 12 parts of polyester modified acrylate, 20 parts of ethylene glycol dimethacrylate, 35 parts of trimethylolpropane trimethacrylate, 8 parts of modifier, 2 parts of triethanolamine, 1 part of isophorone diamine, 4 parts of 1-hydroxycyclohexyl benzophenone, 0.5 parts of BYK-110 dispersant, 0.2 parts of BYK-380 leveling agent, 0.2 parts of BYK-1790 defoamer, 1 part of RAD-2105 matting powder; The structural formula of the modifier is as follows: .

[0018] The preparation method of the modifier is as follows: ; S1: Under nitrogen protection, add 4,4',4''-methylenetriphenol (0.1 mol) and 2,2-dihydroxymethylpropionic acid (0.3 mol) and p-toluenesulfonic acid (1 g) as catalyst into a flask, stir and heat to 140°C for reaction for 5 hours, use a water separator to separate the water generated by the reaction during the reaction, stop introducing nitrogen after the reaction, connect a vacuum pump to reduce pressure and distill until no water is distilled out, cool to room temperature, dissolve with an appropriate amount of acetone, recrystallize in toluene, and filter. The obtained product is the intermediate product; ; S2: Under nitrogen protection, add the intermediate product (0.01 mol) and epichlorohydrin (0.1 mol) into a flask, stir and heat to 110 °C, add 4.5 g of sodium hydroxide, continue to react for 1 h, cool the reaction solution to room temperature, add 100 ml of dichloromethane and 100 ml of deionized water, stir well to separate the dichloromethane phase, add 100 ml of 20 wt% sodium hydroxide solution to wash, separate the dichloromethane phase, dry it with anhydrous sodium sulfate, and concentrate under reduced pressure to obtain the modifier. ESI-MS (m / z) (M + ): Theoretical value 977.07, measured value 977.21.

[0019] Preparation method of the above-mentioned plastic matte UV-curing coating: Under light-proof conditions, first mix aromatic polyurethane modified acrylate, epoxy modified acrylate, polyester modified acrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate and modifier, stir at 200r / min for 30min to make the mixture uniform, then add triethanolamine, isophoronediamine, 1-hydroxycyclohexyl benzophenone, BYK-110 dispersant, BYK-380 leveling agent, BYK-1790 defoamer and RAD-2105 matting powder, and finally stir at 50℃ for 10min.

[0020] Embodiment 2: A plastic matte UV-curing coating, comprising the following components in parts by weight: 12 parts of aromatic polyurethane modified acrylate, 10 parts of epoxy modified acrylate, 10 parts of polyester modified acrylate, 30 parts of ethylene glycol dimethacrylate, 45 parts of trimethylolpropane trimethacrylate, 10 parts of modifier, 2 parts of triethanolamine, 1 part of isophorone diamine, 5 parts of 1-hydroxycyclohexyl benzophenone, 0.5 parts of BYK-110 dispersant, 0.2 parts of BYK-380 leveling agent, 0.2 parts of BYK-1790 defoamer, 1 part of RAD-2105 matting powder; The structural formula and preparation method of the modifier are the same as those of Example 1; Preparation method of the above-mentioned plastic matte UV-curing coating: Under light-proof conditions, first mix aromatic polyurethane modified acrylate, epoxy modified acrylate, polyester modified acrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate and modifier, stir at 200r / min for 30min to make the mixture uniform, then add triethanolamine, isophoronediamine, 1-hydroxycyclohexyl benzophenone, BYK-110 dispersant, BYK-380 leveling agent, BYK-1790 defoamer and RAD-2105 matting powder, and finally stir at 50℃ for 10min.

[0021] Embodiment 3: A plastic matte UV-curing coating, comprising the following components in parts by weight: 10 parts of aromatic polyurethane modified acrylate, 12 parts of epoxy modified acrylate, 12 parts of polyester modified acrylate, 15 parts of ethylene glycol dimethacrylate, 30 parts of trimethylolpropane trimethacrylate, 5 parts of modifier, 2 parts of triethanolamine, 1 part of isophorone diamine, 3 parts of 1-hydroxycyclohexyl benzophenone, 0.5 parts of BYK-110 dispersant, 0.2 parts of BYK-380 leveling agent, 0.2 parts of BYK-1790 defoamer, 1 part of RAD-2105 matting powder; The structural formula and preparation method of the modifier are the same as those of Example 1; Preparation method of the above-mentioned plastic matte UV-curing coating: Under light-proof conditions, first mix aromatic polyurethane modified acrylate, epoxy modified acrylate, polyester modified acrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate and modifier, stir at 200r / min for 30min to make the mixture uniform, then add triethanolamine, isophoronediamine, 1-hydroxycyclohexyl benzophenone, BYK-110 dispersant, BYK-380 leveling agent, BYK-1790 defoamer and RAD-2105 matting powder, and finally stir at 50℃ for 10min.

[0022] Comparative Example 1: The method is basically the same as Example 1, except that aromatic polyurethane modified acrylate of the same mass is used to replace the combination of aromatic polyurethane modified acrylate, epoxy modified acrylate and polyester modified acrylate.

[0023] Comparative Example 2: The method is basically the same as Example 1, except that epoxy-modified acrylate of the same mass is used to replace the combination of aromatic polyurethane-modified acrylate, epoxy-modified acrylate and polyester-modified acrylate.

[0024] Comparative Example 3: The method is basically the same as Example 1, except that polyester-modified acrylate of the same mass is used to replace the combination of aromatic polyurethane-modified acrylate, epoxy-modified acrylate and polyester-modified acrylate.

[0025] Comparative Example 4: The method is basically the same as Example 1, except that no modifier is added.

[0026] Comparative Example 5: The process is substantially the same as Example 1, except that no triethanolamine is added.

[0027] Comparative Example 6: The process is substantially the same as Example 1, except that isophoronediamine is not added.

[0028] Performance Test: The PVC plastic plate was wiped with deionized water and dried for use. The coatings in Examples 1-3 and Comparative Examples 1-6 were evenly coated thereon with a wire rod coater to obtain a coating film with a smooth surface and a thickness of 8 μm. The PVC plastic plate was irradiated under a 5000 W, 300 nm UV lamp for 5 seconds, and the performance of the cured coating was tested. The test results are shown in Table 1 below.

[0029] Adhesion test was carried out with reference to GB / T 9286-1998 "Scratching test for paint and varnish films"; Refer to GB / T 6739-2006 "Determination of film hardness of paints and varnishes by pencil method" for pencil hardness test; Refer to GB / T 31591-2015 "Determination of abrasion resistance of paints and varnishes" for abrasion resistance test;

[0030] It can be seen from Table 1 above that the coating prepared by the present invention has good mechanical properties and strong adhesion to the plastic substrate after UV curing.

[0031] By comparing Example 1 with Comparative Examples 1-3, it can be seen that the film-forming effect of the combination of aromatic polyurethane modified acrylate, epoxy modified acrylate, and polyester modified acrylate is better than the film-forming effect of a single one; By comparing Example 1 with Comparative Example 4, it can be seen that the addition of the modifier can greatly improve the mechanical properties of the coating film formed after the coating is cured and the adhesion to the plastic substrate; By comparing Example 1 with Comparative Examples 5-6, it can be seen that the combination of triethanolamine and isophoronediamine has a greater improvement in the mechanical properties of the coating film formed after the coating is cured.

[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plastic matte UV-curing coating, characterized in that: The invention is composed of the following components in parts by weight: 30-40 parts of acrylic resin, 15-30 parts of bifunctional monomer, 30-45 parts of trifunctional monomer, 5-10 parts of modifier, 1-5 parts of active amine, 3-6 parts of initiator and 1-3 parts of auxiliary agent; The acrylic resin is composed of aromatic polyurethane modified acrylate, epoxy modified acrylate and polyester modified acrylate; The mass ratio of the aromatic polyurethane modified acrylate, epoxy modified acrylate and polyester modified acrylate is 1-3:1-3:1-3; The structural formula of the modifier is as follows: 。 2. The plastic matte UV-curing coating according to claim 1, characterized in that: The preparation method of the modifier is as follows: ； S1: 4,4',4''-methylenetriphenol and 2,2-dihydroxymethylpropionic acid undergo esterification to obtain an intermediate product; ； S2: The intermediate product undergoes a condensation reaction with epichlorohydrin to obtain the modifier.

3. The plastic matte UV-curing coating according to claim 1, characterized in that: The bifunctional monomer is one or a combination of two or more of ethylene glycol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol methacrylate, tripropylene glycol methacrylate, tetraethylene glycol methacrylate, polyethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, propoxylated neopentyl glycol diacrylate, 1,6-ethylene glycol dimethyl diacrylate, phthalic acid dimethacrylate, phthalic acid monoethylene glycol dimethacrylate, ethoxylated bisphenol A dimethacrylate, and hydroxypivalic acid neopentyl glycol monoester dimethacrylate.

4. The plastic matte UV-curing coating according to claim 1, characterized in that: The trifunctional monomer is one or a combination of two or more of trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, glycerol trihydroxypropyl ether triacrylate, and pentaerythritol triacrylate.

5. The plastic matte UV-curing coating according to claim 1, characterized in that: The active amine consists of triethanolamine and isophoronediamine.

6. The plastic matte UV-curing coating according to claim 5, characterized in that: The mass ratio of triethanolamine to isophoronediamine is 1-5:1-5.

7. The plastic matte UV-curing coating according to claim 1, characterized in that: The initiator is one or a combination of two or more of 1-hydroxycyclohexyl benzophenone, p-phenyl benzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone, 2-benzyl-2-methylamino-1-(4-morpholinophenyl)-1-butanone, 2-(4-methylbenzyl)-2-methylamino-1-(4-morpholinophenyl)-1-butanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 4,4'-bis(diethylamino)benzophenone, and isopropylthioxanthone.

8. The plastic matte UV-curing coating according to claim 1, characterized in that: The auxiliary agent includes one or a combination of two or more of a dispersant, a leveling agent, a defoamer and a matting powder.

9. A method for preparing a plastic matte UV-curable coating as claimed in any one of claims 1 to 8, characterized in that: Under light-proof conditions, firstly mix the acrylic resin, bifunctional monomer, trifunctional monomer and modifier evenly, then add the active amine, initiator and auxiliary agent and stir thoroughly.

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