Single-component high-temperature-resistant yellowing-resistant UV (ultraviolet) curing plastic varnish as well as preparation method and application thereof

Abstract

The invention relates to the technical field of coatings, in particular to a single-component high-temperature-resistant and yellowing-resistant UV curing plastic varnish, a preparation method and application. The coating is prepared from the following raw materials in parts by mass: 40-60 parts of resin, 4-7 parts of a photoinitiator, 2-5 parts of fumed silica, 10-25 parts of a polyfunctional reactive diluent, 1 part of an adhesion promoter, 1.6 parts of an anti-yellowing agent, 0.5 part of a defoaming agent, 3 parts of a silane coupling agent, 0.8 part of a flatting agent and 5 parts of a solvent. The prepared coating is stable in performance, good in adhesive force with a plastic substrate, resistant to aging and yellowing and not prone to cracking.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a single-component high-temperature-resistant and yellowing-resistant UV-curing plastic varnish, a preparation method and an application thereof. Background Art

[0002] Light-curing coatings have the advantages of fast curing speed and energy saving. They are a commonly used green and environmentally friendly coating that has been widely used in the protection and decoration of metal, wood and plastic surfaces. The application of light-curing coatings in the field of plastic products can improve the beauty and service life of plastics. However, due to the strong non-polarity of the plastic surface, the interfacial force between the light-curing coating and the plastic substrate is weak; at the same time, the light curing speed is fast, resulting in the internal stress not being released in time, accumulating between the plastic and the coating, causing the coating to peel off from the substrate during long-term use.

[0003] In order to improve adhesion, methods often used include reducing the viscosity of the coating, improving leveling, or adding coupling agents. These methods often need to take into account the mobility of small molecules, the volatility of organic compounds, and the yellowing after curing.

[0004] In view of the above situation, the present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, a preparation method and application thereof. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0006] Resin 40-60 parts

[0007] Photoinitiator 4-7 parts

[0008] 2-5 parts of fumed silica

[0009] 10-25 parts of multifunctional active diluent

[0010] Adhesion promoter 1 part

[0011] 1.6 parts of anti-yellowing agent

[0012] 0.5 parts of defoamer

[0013] Silane coupling agent 3 parts

[0014] 0.8 parts of leveling agent

[0015] 5 parts of solvent.

[0016] As an embodiment of the present invention, the raw materials for preparing the varnish include, in parts by mass:

[0017] Resin 45.5 parts

[0018] Photoinitiator 5.5 parts

[0019] 3 parts of fumed silica

[0020] 15.5 parts of multifunctional active diluent

[0021] Adhesion promoter 1 part

[0022] 1.6 parts of anti-yellowing agent

[0023] 0.5 parts of defoamer

[0024] Silane coupling agent 3 parts

[0025] 0.8 parts of leveling agent

[0026] 5 parts of solvent.

[0027] As an embodiment of the present invention, the preparation method of the resin is as follows:

[0028] S01: 15-40 parts of alicyclic epoxy acrylate monomer, 5-15 parts of acryloyl morpholine (ACMO), and 10-25 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate are added to a reaction kettle for reaction, and heated to 80-100° C. with stirring; then 20-45 parts of alicyclic epoxy acrylate monomer, 15-35 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate (HEMA / HPMA), 1-2 parts of solvent, 0.5-3 parts of initiator and 0.1-0.5 parts of chain transfer agent are added to a mixing container, and stirred until all solids are dissolved to obtain a mixed monomer for standby use;

[0029] Add the above-mentioned mixed monomers to a separating funnel and add dropwise, and control the addition to be completed within 2-3 hours; after the addition is completed, reflux and keep warm at 80-100°C for 2-4 hours; then increase the temperature by 8-15°C and react for another 1-2 hours; finally increase the temperature to 115-125°C and reflux for 0.5-1.5 hours to consume all the remaining initiator, and cool to obtain an alicyclic epoxy acrylate copolymer solution;

[0030] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0031] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01, adjust the temperature to 90-100°C, add 0.3-2 parts of catalyst, 0.05-0.5 parts of antioxidant, 0.05-0.8 parts of polymerization inhibitor, and then drip 9-16 parts of acrylic acid (equivalent to an excess of 1-5% of epoxy groups) into the reaction kettle evenly, and control the dripping time to be 30-40 minutes; then heat to 105-115°C, keep the temperature for about 7-9 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0032] S03: Synthesis of UV resin:

[0033] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 95-100°C, add 8-18 parts of acid anhydride, then slowly heat to 105-112°C, keep the reaction warm for about 3-5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0034] As an embodiment of the present invention, the acid anhydride is one or two of maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0035] As an embodiment of the present invention, the acid anhydride is one or two of maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0036] As an embodiment of the present invention, the photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0037] As an embodiment of the present invention, the multifunctional reactive diluent comprises one or more of trimethylolpropane triacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and tripropylene glycol diacrylate.

[0038] As an embodiment of the present invention, the adhesion promoter includes a phosphate adhesion promoter.

[0039] As an embodiment of the present invention, the preparation method of the one-component high temperature resistant and yellowing resistant UV curing plastic varnish comprises the following steps:

[0040] S1. Add the resin and active diluent to the solvent in sequence and pre-disperse for 8-12 minutes at a dispersion speed of 300-500 r / min;

[0041] S2. At a speed of 300-500 r / min, add adhesion promoter, anti-yellowing agent, defoaming agent and leveling agent to step S1 in sequence and pre-disperse for 8-12 minutes;

[0042] S3, at a speed of 300-500 r / min, add the remaining raw materials to step S2 in sequence, pre-disperse for 3-7 min, and high-speed disperse at a speed of 1500-2000 r / min for 25-35 min;

[0043] S4. Stop dispersing, test the sample to see if it is qualified, and obtain the finished product.

[0044] As an embodiment of the present invention, the one-component high temperature resistant and yellowing resistant UV curing plastic varnish is applied in the field of plastic coatings.

[0045] By adopting the above technical solution, the present invention has the following beneficial effects:

[0046] The coating prepared by the invention has stable performance, good adhesion to the plastic substrate, resistance to aging and yellowing, and is not easy to crack. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0048] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0049] Resin 45.5 parts

[0050] Photoinitiator 5.5 parts

[0051] 3 parts of fumed silica

[0052] 15.5 parts of multifunctional active diluent

[0053] Adhesion promoter 1 part

[0054] 1.6 parts of anti-yellowing agent

[0055] 0.5 parts of defoamer

[0056] Silane coupling agent 3 parts

[0057] 0.8 parts of leveling agent

[0058] 5 parts of solvent.

[0059] Resin

[0060] The preparation method of the resin is as follows:

[0061] S01: 15-40 parts of alicyclic epoxy acrylate monomer, 5-15 parts of acryloyl morpholine (ACMO), and 10-25 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate are added to a reaction kettle for reaction, and heated to 80-100° C. with stirring; then 20-45 parts of alicyclic epoxy acrylate monomer, 15-35 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate (HEMA / HPMA), 1-2 parts of solvent, 0.5-3 parts of initiator and 0.1-0.5 parts of chain transfer agent are added to a mixing container, and stirred until all solids are dissolved to obtain a mixed monomer for standby use;

[0062] Add the above-mentioned mixed monomers to a separating funnel and add dropwise, and control the addition to be completed within 2-3 hours; after the addition is completed, reflux and keep warm at 80-100°C for 2-4 hours; then increase the temperature by 8-15°C and react for another 1-2 hours; finally increase the temperature to 115-125°C and reflux for 0.5-1.5 hours to consume all the remaining initiator, and cool to obtain an alicyclic epoxy acrylate copolymer solution;

[0063] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0064] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01, adjust the temperature to 90-100°C, add 0.3-2 parts of catalyst, 0.05-0.5 parts of antioxidant, 0.05-0.8 parts of polymerization inhibitor, and then drip 9-16 parts of acrylic acid (equivalent to an excess of 1-5% of epoxy groups) into the reaction kettle evenly, and control the dripping time to be 30-40 minutes; then heat to 105-115°C, keep the temperature for about 7-9 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0065] S03: Synthesis of UV resin:

[0066] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 95-100°C, add 8-18 parts of acid anhydride, then slowly heat to 105-112°C, keep the reaction warm for about 3-5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0067] The acid anhydride is one or two of maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride and methylhexahydrophthalic anhydride.

[0068] In the present invention, in the preparation of the resin, the solvent is toluene; the initiator is tert-butyl peroxide; thiopropionic acid; the chain transfer agent is triphenylphosphine; the antioxidant is MIANOX PEP-36; and the inhibitor is inhibitor 510.

[0069] Photoinitiator

[0070] The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0071] As an embodiment of the present invention, the photoinitiator further comprises substance A, and the preparation method of substance A is as follows: 0.645 g of 2,4,6-trimethylbenzoylphenylphosphonic acid and 15 ml of anhydrous dichloromethane are mixed and dissolved, 0.41 ml of oxalyl chloride is added in an ice-water bath and reacted until there is no gas, and then the reaction is continued at 25°C for 24 hours, and after reduced pressure evaporation, 15 ml of anhydrous dichloromethane and 0.41 ml of polyethylene glycol are added, and the reaction is carried out at 25°C for 24 hours, and then the substance A is purified and rotary evaporated; wherein the molecular weight of the polyethylene glycol is 113.

[0072] Multifunctional reactive diluent

[0073] The multifunctional reactive diluent comprises one or more of trimethylolpropane triacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and tripropylene glycol diacrylate.

[0074] As an embodiment of the present invention, the multifunctional reactive diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate, and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0075] Adhesion promoter

[0076] The adhesion promoter is a phosphate adhesion promoter, specifically Santuo Chemical LRD-3.

[0077] Anti-yellowing agent

[0078] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0079] Defoaming agent

[0080] The defoaming agent is Digo 810.

[0081] Silane coupling agent

[0082] The silane coupling agent described in the present invention is KH-570.

[0083] Leveling agent

[0084] The leveling agent in the present invention is Troy 486CFL.

[0085] Solvents

[0086] The solvent in the present invention is ethyl acetate.

[0087] The preparation method of the one-component high temperature resistant and yellowing resistant UV curing plastic varnish comprises the following steps:

[0088] S1. Add the resin and active diluent to the solvent in sequence and pre-disperse for 8-12 minutes at a dispersion speed of 300-500 r / min;

[0089] S2. At a speed of 300-500 r / min, add adhesion promoter, anti-yellowing agent, defoaming agent and leveling agent to step S1 in sequence and pre-disperse for 8-12 minutes;

[0090] S3, at a speed of 300-500 r / min, add the remaining raw materials to step S2 in sequence, pre-disperse for 3-7 min, and high-speed disperse at a speed of 1500-2000 r / min for 25-35 min;

[0091] S4. Stop dispersing, test the sample to see if it is qualified, and obtain the finished product.

[0092] The present invention is further explained below in conjunction with specific implementation modes.

[0093] Example 1

[0094] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0095] Resin 45.5 parts

[0096] Photoinitiator 5.5 parts

[0097] 3 parts of fumed silica

[0098] 15.5 parts of multifunctional active diluent

[0099] Adhesion promoter 1 part

[0100] 1.6 parts of anti-yellowing agent

[0101] 0.5 parts of defoamer

[0102] Silane coupling agent 3 parts

[0103] 0.8 parts of leveling agent

[0104] 5 parts of solvent.

[0105] Resin: The preparation method of the resin is as follows:

[0106] S01: 25 parts of alicyclic epoxy acrylate monomer, 8 parts of acrylamide morpholine (ACMO), and 15 parts of hydroxypropyl methacrylate are added to a reactor for reaction, and the mixture is stirred and heated to 90° C.; then 28 parts of alicyclic epoxy acrylate monomer, 17 parts of hydroxyethyl methacrylate, 1 part of solvent, 1.5 parts of initiator, and 0.3 parts of chain transfer agent are added to a mixing container, and the mixture is stirred until all the solids are dissolved to obtain a mixed monomer for standby use;

[0107] The mixed monomers are added to a separatory funnel and added dropwise within 3 hours. After the addition is completed, the mixture is refluxed and kept at 85°C for 3 hours. The temperature is then raised by 10°C and the mixture is reacted for another 1.5 hours. Finally, the temperature is raised to 120°C and refluxed for 0.8 hours to consume all the remaining initiators. The mixture is cooled to obtain an alicyclic epoxy acrylate copolymer solution.

[0108] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0109] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01 by weight, adjust the temperature to 95°C, add 0.8 parts of catalyst, 0.16 parts of antioxidant, and 0.24 parts of polymerization inhibitor, and then drip 13.2 parts of acrylic acid evenly into the reaction kettle, and control the dripping to be completed within 40 minutes; then heat to 110°C, keep the temperature and react for about 8 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0110] S03: Synthesis of UV resin:

[0111] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 98°C, add 12 parts of maleic anhydride, and then slowly raise the temperature to 110°C. Keep the reaction warm for about 3.5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0112] The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone and substance A, and the mass ratio is 2:1.

[0113] The preparation method of the substance A is as follows: 0.645 g of 2,4,6-trimethylbenzoylphenylphosphonic acid and 15 ml of anhydrous dichloromethane are mixed and dissolved, 0.41 ml of oxalyl chloride is added in an ice-water bath, the mixture is reacted until there is no gas, and then the reaction is continued at 25° C. for 24 hours. After reduced pressure evaporation, 15 ml of anhydrous dichloromethane and 0.41 ml of polyethylene glycol are added, the mixture is reacted at 25° C. for 24 hours, and then the substance A is purified and rotary evaporated; wherein the molecular weight of the polyethylene glycol is 113.

[0114] The multifunctional active diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0115] The adhesion promoter is a phosphate adhesion promoter, specifically Santuo Chemical LRD-3.

[0116] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0117] The defoaming agent is Digo 810.

[0118] The silane coupling agent is KH-570.

[0119] The leveling agent is Troy 486CFL.

[0120] The solvent is ethyl acetate.

[0121] Example 2

[0122] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0123] Resin 45.5 parts

[0124] Photoinitiator 5.5 parts

[0125] 3 parts of fumed silica

[0126] 15.5 parts of multifunctional active diluent

[0127] Adhesion promoter 1 part

[0128] 1.6 parts of anti-yellowing agent

[0129] 0.5 parts of defoamer

[0130] Silane coupling agent 3 parts

[0131] 0.8 parts of leveling agent

[0132] 5 parts of solvent.

[0133] Resin: The preparation method of the resin is as follows:

[0134] S01: 25 parts of alicyclic epoxy acrylate monomer, 8 parts of acrylamide morpholine (ACMO), and 15 parts of hydroxypropyl methacrylate are added to a reactor for reaction, and the mixture is stirred and heated to 90° C.; then 28 parts of alicyclic epoxy acrylate monomer, 17 parts of hydroxyethyl methacrylate, 1 part of solvent, 1.5 parts of initiator, and 0.3 parts of chain transfer agent are added to a mixing container, and the mixture is stirred until all the solids are dissolved to obtain a mixed monomer for standby use;

[0135] The mixed monomers are added to a separatory funnel and added dropwise within 3 hours. After the addition is completed, the mixture is refluxed and kept at 85°C for 3 hours. The temperature is then raised by 10°C and the mixture is reacted for another 1.5 hours. Finally, the temperature is raised to 120°C and refluxed for 0.8 hours to consume all the remaining initiators. The mixture is cooled to obtain an alicyclic epoxy acrylate copolymer solution.

[0136] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0137] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01 by weight, adjust the temperature to 95°C, add 0.8 parts of catalyst, 0.16 parts of antioxidant, and 0.24 parts of polymerization inhibitor, and then drip 13.2 parts of acrylic acid evenly into the reaction kettle, and control the dripping to be completed within 40 minutes; then heat to 110°C, keep the temperature and react for about 8 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0138] S03: Synthesis of UV resin:

[0139] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 98°C, add 12 parts of maleic anhydride, and then slowly raise the temperature to 110°C. Keep the reaction warm for about 3.5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0140] The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0141] The multifunctional active diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0142] The adhesion promoter is a phosphate adhesion promoter, specifically Santuo Chemical LRD-3.

[0143] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0144] The defoaming agent is Digo 810.

[0145] The silane coupling agent is KH-570.

[0146] The leveling agent is Troy 486CFL.

[0147] The solvent is ethyl acetate.

[0148] Example 3

[0149] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0150] Resin 45.5 parts

[0151] Photoinitiator 5.5 parts

[0152] 3 parts of fumed silica

[0153] 15.5 parts of multifunctional active diluent

[0154] Adhesion promoter 1 part

[0155] 1.6 parts of anti-yellowing agent

[0156] 0.5 parts of defoamer

[0157] Silane coupling agent 3 parts

[0158] 0.8 parts of leveling agent

[0159] 5 parts of solvent.

[0160] Resin: The preparation method of the resin is as follows:

[0161] S01: 25 parts of alicyclic epoxy acrylate monomer, 8 parts of acrylamide morpholine (ACMO), and 15 parts of hydroxypropyl methacrylate are added to a reactor for reaction, and the mixture is stirred and heated to 90° C.; then 28 parts of alicyclic epoxy acrylate monomer, 17 parts of hydroxyethyl methacrylate, 1 part of solvent, 1.5 parts of initiator, and 0.3 parts of chain transfer agent are added to a mixing container, and the mixture is stirred until all the solids are dissolved to obtain a mixed monomer for standby use;

[0162] The mixed monomers are added to a separatory funnel and added dropwise within 3 hours. After the addition is completed, the mixture is refluxed and kept at 85°C for 3 hours. The temperature is then raised by 10°C and the mixture is reacted for another 1.5 hours. Finally, the temperature is raised to 120°C and refluxed for 0.8 hours to consume all the remaining initiators. The mixture is cooled to obtain an alicyclic epoxy acrylate copolymer solution.

[0163] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0164] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01 by weight, adjust the temperature to 95°C, add 0.8 parts of catalyst, 0.16 parts of antioxidant, and 0.24 parts of polymerization inhibitor, and then drip 13.2 parts of acrylic acid evenly into the reaction kettle, and control the dripping to be completed within 40 minutes; then heat to 110°C, keep the temperature and react for about 8 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0165] S03: Synthesis of UV resin:

[0166] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 98°C, add 12 parts of maleic anhydride, and then slowly raise the temperature to 110°C. Keep the reaction warm for about 3.5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0167] The photoinitiator comprises substance A.

[0168] The preparation method of the substance A is as follows: 0.645 g of 2,4,6-trimethylbenzoylphenylphosphonic acid and 15 ml of anhydrous dichloromethane are mixed and dissolved, 0.41 ml of oxalyl chloride is added in an ice-water bath, the mixture is reacted until there is no gas, and then the reaction is continued at 25° C. for 24 hours. After reduced pressure evaporation, 15 ml of anhydrous dichloromethane and 0.41 ml of polyethylene glycol are added, the mixture is reacted at 25° C. for 24 hours, and then the substance A is purified and rotary evaporated; wherein the molecular weight of the polyethylene glycol is 113.

[0169] The multifunctional active diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0170] The adhesion promoter is a phosphate adhesion promoter, specifically Santuo Chemical LRD-3.

[0171] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0172] The defoaming agent is Digo 810.

[0173] The silane coupling agent is KH-570.

[0174] The leveling agent is Troy 486CFL.

[0175] The solvent is ethyl acetate.

[0176] Example 4

[0177] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0178] Resin 45.5 parts

[0179] Photoinitiator 5.5 parts

[0180] 3 parts of fumed silica

[0181] 15.5 parts of multifunctional active diluent

[0182] Adhesion promoter 1 part

[0183] 1.6 parts of anti-yellowing agent

[0184] 0.5 parts of defoamer

[0185] Silane coupling agent 3 parts

[0186] 0.8 parts of leveling agent

[0187] 5 parts of solvent.

[0188] The resin is DSM Neocryl B-725 solid acrylic resin.

[0189] The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone and substance A, and the mass ratio is 2:1.

[0190] The preparation method of the substance A is as follows: 0.645 g of 2,4,6-trimethylbenzoylphenylphosphonic acid and 15 ml of anhydrous dichloromethane are mixed and dissolved, 0.41 ml of oxalyl chloride is added in an ice-water bath, the mixture is reacted until there is no gas, and then the reaction is continued at 25° C. for 24 hours. After reduced pressure evaporation, 15 ml of anhydrous dichloromethane and 0.41 ml of polyethylene glycol are added, the mixture is reacted at 25° C. for 24 hours, and then the substance A is purified and rotary evaporated; wherein the molecular weight of the polyethylene glycol is 113.

[0191] The multifunctional active diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0192] The adhesion promoter is a phosphate adhesion promoter, specifically Santuo Chemical LRD-3.

[0193] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0194] The defoaming agent is Digo 810.

[0195] The silane coupling agent is KH-570.

[0196] The leveling agent is Troy 486CFL.

[0197] The solvent is ethyl acetate.

[0198] Example 5

[0199] The present invention provides a one-component high temperature resistant and yellowing resistant UV curing plastic varnish, wherein the raw materials for its preparation comprise, in parts by mass:

[0200] Resin 45.5 parts

[0201] Photoinitiator 5.5 parts

[0202] 3 parts of fumed silica

[0203] 15.5 parts of multifunctional active diluent

[0204] Adhesion promoter 1 part

[0205] 1.6 parts of anti-yellowing agent

[0206] 0.5 parts of defoamer

[0207] Silane coupling agent 3 parts

[0208] 0.8 parts of leveling agent

[0209] 5 parts of solvent.

[0210] Resin: The preparation method of the resin is as follows:

[0211] S01: 25 parts of alicyclic epoxy acrylate monomer, 8 parts of acrylamide morpholine (ACMO), and 15 parts of hydroxypropyl methacrylate are added to a reactor for reaction, and the mixture is stirred and heated to 90° C.; then 28 parts of alicyclic epoxy acrylate monomer, 17 parts of hydroxyethyl methacrylate, 1 part of solvent, 1.5 parts of initiator, and 0.3 parts of chain transfer agent are added to a mixing container, and the mixture is stirred until all the solids are dissolved to obtain a mixed monomer for standby use;

[0212] The mixed monomers are added to a separatory funnel and added dropwise within 3 hours. After the addition is completed, the mixture is refluxed and kept at 85°C for 3 hours. The temperature is then raised by 10°C and the mixture is reacted for another 1.5 hours. Finally, the temperature is raised to 120°C and refluxed for 0.8 hours to consume all the remaining initiators. The mixture is cooled to obtain an alicyclic epoxy acrylate copolymer solution.

[0213] S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer:

[0214] Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01 by weight, adjust the temperature to 95°C, add 0.8 parts of catalyst, 0.16 parts of antioxidant, and 0.24 parts of polymerization inhibitor, and then drip 13.2 parts of acrylic acid evenly into the reaction kettle, and control the dripping to be completed within 40 minutes; then heat to 110°C, keep the temperature and react for about 8 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution;

[0215] S03: Synthesis of UV resin:

[0216] Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 98°C, add 12 parts of maleic anhydride, and then slowly raise the temperature to 110°C. Keep the reaction warm for about 3.5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain a high temperature resistant and yellowing resistant alkali-soluble UV resin.

[0217] The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone and substance A, and the mass ratio is 2:1.

[0218] The preparation method of the substance A is as follows: 0.645 g of 2,4,6-trimethylbenzoylphenylphosphonic acid and 15 ml of anhydrous dichloromethane are mixed and dissolved, 0.41 ml of oxalyl chloride is added in an ice-water bath, the mixture is reacted until there is no gas, and then the reaction is continued at 25° C. for 24 hours. After reduced pressure evaporation, 15 ml of anhydrous dichloromethane and 0.41 ml of polyethylene glycol are added, the mixture is reacted at 25° C. for 24 hours, and then the substance A is purified and rotary evaporated; wherein the molecular weight of the polyethylene glycol is 113.

[0219] The multifunctional active diluent comprises trimethylolpropane triacrylate, tripropylene glycol diacrylate and 1,6-hexanediol diacrylate, and the mass ratio is 1:1:1.

[0220] The adhesion promoter is silane coupling agent KH-560.

[0221] The anti-yellowing agent is 2-hydroxy-4-methoxybenzophenone.

[0222] The defoaming agent is Digo 810.

[0223] The silane coupling agent is KH-570.

[0224] The leveling agent is Troy 486CFL.

[0225] The solvent is ethyl acetate.

[0226] Performance Testing

[0227] The coatings prepared in Examples 1 to 5 were placed at 40° C. for 120 days and then subjected to performance testing.

[0228] Test 1: The coating was applied to the surface of the plastic substrate, the dry film thickness was controlled at 15-20 μm, and the coating was applied at 800 mJ / cm 2 Energy curing, test results see Table 1.

[0229] Friction resistance: using a color fastness tester, positive pressure 9N, contact head 6.6cm2, linear motion rate 60 times / min, stroke 100mm, friction sandpaper 3M self-adhesive type 2400, reciprocating 15 times, gloss loss rate (20°) ≤35% is qualified.

[0230] Pencil hardness: GB / T 6739-2006.

[0231] Adhesion test: GBT9286-1998

[0232] Table 1 Performance test

[0233] Example Appearance Pencil hardness Friction resistance Adhesion test Example 1 Uniform gloss H Light loss rate ≤35% >Level 1 Example 2 Uniform gloss H Light loss rate ≤35% Level 1 Example 3 Uneven gloss HB Light loss rate ≤35% Level 1 Example 4 Uniform gloss HB Light loss rate ≤35% Level 1 Example 5 Uneven gloss H Light loss rate ≤35% Level 1

[0234] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish, characterized in that: In parts by mass, the raw materials for its preparation include: Resin 40-60 parts Photoinitiator 4-7 parts 2-5 parts of fumed silica 10-25 parts of multifunctional active diluent Adhesion promoter 1 part 1.6 parts of anti-yellowing agent 0.5 parts of defoamer Silane coupling agent 3 parts 0.8 parts of leveling agent 5 parts of solvent.

2. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1, characterized in that: In parts by mass, the raw materials for its preparation include: Resin 45.5 parts Photoinitiator 5.5 parts 3 parts of fumed silica 15.5 parts of multifunctional active diluent Adhesion promoter 1 part 1.6 parts of anti-yellowing agent 0.5 parts of defoamer Silane coupling agent 3 parts 0.8 parts of leveling agent 5 parts of solvent.

3. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: The preparation method of the resin is as follows: S01: 15-40 parts of alicyclic epoxy acrylate monomer, 5-15 parts of acryloyl morpholine, and 10-25 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate are added to a reaction kettle for reaction, and heated to 80-100° C. with stirring; then 20-45 parts of alicyclic epoxy acrylate monomer, 15-35 parts of hydroxyethyl methacrylate or hydroxypropyl methacrylate, 1-2 parts of solvent, 0.5-3 parts of initiator and 0.1-0.5 parts of chain transfer agent are added to a mixing container, and stirred until all solids are dissolved to obtain a mixed monomer for standby use; Add the above-mentioned mixed monomers to a separating funnel and add dropwise, and control the addition to be completed within 2-3 hours; after the addition is completed, reflux and keep warm at 80-100°C for 2-4 hours; then increase the temperature by 8-15°C and react for another 1-2 hours; finally increase the temperature to 115-125°C and reflux for 0.5-1.5 hours to consume all the remaining initiator, and cool to obtain an alicyclic epoxy acrylate copolymer solution; S02: Acrylic modification of cycloaliphatic epoxy acrylate copolymer: Take 100 parts of the alicyclic epoxy acrylate copolymer solution synthesized in S01, adjust the temperature to 90-100°C, add 0.3-2 parts of catalyst, 0.05-0.5 parts of antioxidant, 0.05-0.8 parts of polymerization inhibitor, and then drip 9-16 parts of acrylic acid (equivalent to an excess of 1-5% of epoxy groups) into the reaction kettle evenly, and control the dripping time to be 30-40 minutes; then heat to 105-115°C, keep the temperature for about 7-9 hours, until the acid value drops below 3.5 mgKOH / g and the epoxy Ev value drops below 3 mgKOH / g to stop the reaction, and obtain an acrylic acid-modified epoxy acrylate copolymer UV resin solution; S03: Synthesis of UV resin: Take 100 parts of the acrylic acid-modified epoxy acrylate copolymer UV resin solution in S02 by mass, adjust the temperature to 95-100°C, add 8-18 parts of acid anhydride, then slowly heat to 105-112°C, keep the reaction warm for about 3-5 hours, monitor the acid value during the reaction process until the acid value no longer changes, and obtain the resin.

4. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 3, characterized in that: The acid anhydride is one or two of maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride.

5. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 3, characterized in that: The acid anhydride is one or two of maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride.

6. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: The photoinitiator comprises 2-hydroxy-2-methyl-1-phenyl-1-propanone.

7. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: The multifunctional reactive diluent comprises one or more of trimethylolpropane triacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and tripropylene glycol diacrylate.

8. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: The adhesion promoter comprises a phosphate adhesion promoter.

9. The method for preparing a one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: Here are the steps: S1. Add the resin and active diluent to the solvent in sequence and pre-disperse for 8-12 minutes at a dispersion speed of 300-500 r / min; S2. At a speed of 300-500 r / min, add adhesion promoter, anti-yellowing agent, defoaming agent and leveling agent to step S1 in sequence and pre-disperse for 8-12 minutes; S3, at a speed of 300-500 r / min, add the remaining raw materials to step S2 in sequence, pre-disperse for 3-7 min, and high-speed disperse at a speed of 1500-2000 r / min for 25-35 min; S4. Stop dispersing, test the sample to see if it is qualified, and obtain the finished product.

10. A one-component high temperature resistant and yellowing resistant UV curing plastic varnish according to claim 1 or 2, characterized in that: Used in the field of plastic coating.