LED-moisture dual-curing organic silicon modified hyperbranched polyurethane acrylic resin as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of polymer materials, and provides LED-moisture dual-curing organic silicon modified hyperbranched polyurethane acrylic resin as well as a preparation method and application thereof. The preparation method comprises the following steps: firstly, taking first polyhydric alcohol and polyatomic acid as raw materials, preparing a hyperbranched polyester prepolymer containing hydroxyl at the tail end through a first reaction, and further performing a second reaction with an isocyanate compound and second polyhydric alcohol to prepare a hyperbranched polyurethane prepolymer containing isocyanate groups at the tail end; the coating further prepared from the organosilicon modified hyperbranched polyurethane acrylic resin not only can be subjected to UV curing, but also can be subjected to LED curing and moisture curing, energy required by curing is low, curing is 100%, environment friendliness is achieved, VOC is zero, the flash point is 95 DEG C or above, the product curing speed is high, the viscosity is low, and the coating can be widely applied to the field of high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing, high-temperature curing and high-temperature curing. The paint has the advantages of good flexibility, good film-forming property, strong adhesive force and excellent weather resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and more specifically, to a silicone-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing, a preparation method thereof, and an application thereof. Background Art

[0002] Currently, the radiation-curable materials mainly include solvent-based single-curing UV materials. The shadow areas and shielding areas of ordinary single-curing UV materials cannot be cured, and they tend to be cured for flat materials, while full-round curing cannot be achieved for circuit boards and devices with many plug-ins.

[0003] The service life of traditional UV lamps is about 800 - 1500h, while the service life of LED curing equipment is up to more than 15000h, significantly reducing the replacement frequency and cost of the lamps; at the same time, LED curing is more power-saving, and the standby power consumption is almost zero, and the overall energy consumption is reduced by more than 70% compared with UV curing; after the traditional UV lamp is turned on, it generally takes 3 - 5min to reach a stable state, and it takes 5 - 10min to turn off after use, while the LED lamp can be used immediately, reaching 100% power output immediately, and the power supply can be directly turned off after use, which is time-saving and efficient; moreover, LED curing is more environmentally friendly. In addition, ozone is generated instantaneously when the traditional UV lamp is turned on. The UV lamp is a mercury lamp, and improper handling will cause serious pollution, while the LED lamp does not contain pollutants and meets the environmental protection requirements better. Therefore, LED-curable coatings have gradually become a hot spot in the development of radiation coatings. However, there are few LED-curable materials on the market at present, and they mainly have a single-curing chain structure, with slow curing speed, incomplete curing, poor weather resistance, brittle paint films, and the shadow areas and shielding areas cannot be cured. Organic solvents need to be used, which is not environmentally friendly, seriously restricting their application directions and market promotion.

[0004] Aiming at the above problems, it is urgent to develop a material that can achieve LED curing, where both the shadow areas and shielding areas can be cured, with fast curing speed, complete curing, excellent weather resistance, good flexibility of the paint film, without the need to use organic solvents, and environmentally friendly. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. For this purpose, the present invention provides a silicone-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing, a preparation method thereof, and an application thereof. The silicone-modified hyperbranched polyurethane acrylate resin provided by the present invention can be cured by UV, LED, and moisture, so both the shadow areas and shielding areas can be cured, 100% curing can be achieved, the curing is complete, the curing speed is fast, the curing time is short, the coating prepared therefrom can be used immediately after brushing, greatly improving the production and use efficiency, with excellent weather resistance, good flexibility of the paint film, without the need to use organic solvents, and environmentally friendly.

[0006] The first aspect of the present invention provides a preparation method of a silicone-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing.

[0007] Specifically, a preparation method of a silicone-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing includes the following steps:

[0008] (1) In an atmosphere of a protective gas, under the action of catalyst A, a first reaction occurs between a first polyol and a polybasic acid to obtain a hyperbranched polyester prepolymer with hydroxyl groups at the ends.

[0009] (2) Under the action of an organobismuth catalyst, a second reaction occurs between the hyperbranched polyester prepolymer with hydroxyl groups at the ends, an isocyanate compound, and a second polyol to obtain a hyperbranched polyurethane prepolymer with isocyanate groups at the ends.

[0010] (3) A third reaction occurs between the hyperbranched polyurethane prepolymer with isocyanate groups at the ends, hydroxyacrylic acid, and organosiloxane to obtain the silicone-modified hyperbranched polyurethane acrylate resin.

[0011] The present invention prepares a silicone-modified hyperbranched polyurethane acrylate resin that can achieve LED-moisture dual curing through three-step reactions. Due to its three-dimensional spherical multi-branched structure, compared with chain-shaped resins, it has the characteristics of fast reaction speed, low product viscosity, high peripheral functionality, strong reactivity, and faster and more complete LED curing. At the same time, it has good flexibility, strong adhesion, and excellent weather resistance. The acrylate groups in the resin structure can help achieve UV curing and LED curing, and the terminal isocyanate groups can also achieve moisture curing, thus solving the problem that the shadow areas and shielding areas that cannot be irradiated by LED cannot be cured, realizing 100% curing, and also solving the problems of high energy consumption and environmental unfriendliness of traditional UV curing. It has the characteristics of both LED-moisture dual curing and can extend the application of radiation curing materials from planar applications to more other application scenarios. At the same time, due to the introduction of silane coupling agents, Si-O bonds are bonded in the molecular structure. The Si-O bond has a long bond length, high bond energy, strong binding ability, good adhesion, strong stability, is partially ionized, and has partial double bond characteristics, further improving the weather resistance, stability, adhesion, and bonding performance of the product.

[0012] Preferably, in step (1), the molar ratio of the first polyol to the polybasic acid is (1.0 - 1.5):1.

[0013] Preferably, in step (2), the molar ratio of the hyperbranched polyester prepolymer with hydroxyl groups at the ends, the isocyanate compound, and the second polyol is (4 - 5):(1.8 - 2.5):1.

[0014] Preferably, in step (3), the molar ratio of the hyperbranched polyurethane prepolymer with an isocyanate group (NCO) at the end, hydroxy acrylic acid, and organosiloxane is (15 - 20):(3 - 4):1.

[0015] Preferably, in step (1), the catalyst A is at least one of p-toluenesulfonic acid, heteropolyacid, solid superacid, strongly acidic cation exchange resin, tetrabutyl titanate, phosphoric acid, and phosphorous acid.

[0016] Preferably, in step (1), the temperature of the first reaction is 100 - 115 °C, and / or the time of the first reaction is 2 - 3 h.

[0017] Preferably, in step (1), the first polyol is pentaerythritol.

[0018] Preferably, in step (1), the polybasic acid is 2,2-dimethylolpropionic acid.

[0019] In the first reaction, the hydroxyl group in pentaerythritol and the carboxyl group in 2,2-dimethylolpropionic acid undergo an esterification reaction to obtain a hyperbranched polyester prepolymer with a hydroxyl group at the end. The reaction equation for a single-molecule raw material is as follows:

[0020]

[0021] Preferably, in step (1), the protective gas is nitrogen.

[0022] Preferably, in step (2), the second polyol is at least one of polyethylene glycol, polypropylene glycol, propylene glycol block polyether, polyester polyol, 1,4-butanediol (BDO), 1,6-hexanediol (HD), neopentyl glycol (NPG), and diethylene glycol (EG).

[0023] Preferably, in step (2), the isocyanate compound is at least one of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), polymethylene polyphenyl polyisocyanate (PAPI), and hexamethylene diisocyanate (HDI).

[0024] Preferably, in step (2), the second reaction specifically includes the following steps: First, mix the hyperbranched polyester prepolymer with a hydroxyl group at the end and the second polyol, then add an organic bismuth catalyst (environmentally friendly catalyst), heat up to 55 - 85 °C, and then dropwise add the isocyanate compound while controlling the temperature below 85 °C. After the isocyanate compound is added dropwise, keep it warm at 80 - 90 °C for 1 - 2 h to carry out the second reaction.

[0025] Preferably, in step (2), the second reaction is carried out in a protective gas atmosphere.

[0026] Preferably, in step (2), the protective gas is nitrogen.

[0027] In the second reaction, the isocyanate compound (NCO) reacts with the hydroxyl groups (the hydroxyl groups of the hyperbranched polyester prepolymer with hydroxyl groups at the end and the hydroxyl groups of the second polyol) to form a hyperbranched polyurethane prepolymer with isocyanate groups at the end.

[0028] Preferably, in step (3), the third reaction ends when the NCO content reaches 4-5%.

[0029] Preferably, in step (3), the third reaction specifically includes the following steps: placing the hyperbranched polyurethane prepolymer with isocyanate groups at the end at 55-65 °C, dropping organosiloxane and hydroxyacrylate into it, keeping the temperature for the third reaction for 3-6 h after dropping, terminating the reaction when the NCO content in the system reaches 4-5%, and obtaining the organosilicon-modified hyperbranched polyurethane acrylate resin.

[0030] Preferably, the organobismuth catalyst is at least one of bismuth octoate (such as DY-20), bismuth isooctoate, and bismuth neodecanoate.

[0031] Preferably, in step (3), the organosiloxane is at least one of 3-triethoxysilyl-1-propylamine, γ-glycidyletheroxypropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidyletheroxypropyltrimethoxysilane, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane.

[0032] Preferably, in step (3), the hydroxyacrylate is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, 2-oxo-tetrahydrofuran-3-hydroxy-methyl acrylate, 4-hydroxybutyl acrylate, hydroxyethyl methacrylate, and hydroxybutyl acrylate.

[0033] The second aspect of the present invention provides an organosilicon-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing.

[0034] An organosilicon-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing is prepared by using the preparation method of the organosilicon-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing. The viscosity of the organosilicon-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing at 25 °C is 3000-5000 mPa·s.

[0035] Preferably, the viscosity of the organosilicon-modified hyperbranched polyurethane acrylate resin with LED-moisture dual curing at 25 °C is 3000-4000 mPa·s.

[0036] The third aspect of the present invention provides an application of an organosilicon-modified hyperbranched polyurethane acrylate resin with dual curing of LED and moisture.

[0037] An application of an organosilicon-modified hyperbranched polyurethane acrylate resin with dual curing of LED and moisture in the preparation of coatings, inks or adhesives.

[0038] The fourth aspect of the present invention provides a coating.

[0039] A coating, comprising the following raw material components: the organosilicon-modified hyperbranched polyurethane acrylate resin, an active monomer, an antifoaming agent, a wetting and leveling agent, and a photoinitiator.

[0040] Preferably, by weight, the coating comprises the following raw material components: 40-60 parts of the organosilicon-modified hyperbranched polyurethane acrylate resin, 30-50 parts of the active monomer, 0.1-0.7 parts of the antifoaming agent, 1-2 parts of the wetting and leveling agent, and 4-6 parts of the photoinitiator.

[0041] Preferably, the coating further comprises color powder. The coating containing color powder is mainly for the color display function and is also called ink.

[0042] More preferably, by weight, the coating further comprises 0.1-1.5 parts of color powder.

[0043] Preferably, the active monomer is at least one of butyl acrylate, isooctyl acrylate, tetrahydrofurfuryl methacrylate, dodecyl acrylate, acryloylmorpholine, lauryl acrylate, isobornyl methacrylate, isobornyl acrylate.

[0044] Preferably, the antifoaming agent is at least one of organosilicon antifoaming agent, polyether antifoaming agent, polyether-modified silicone antifoaming agent, mineral oil antifoaming agent.

[0045] Preferably, the wetting and leveling agent is at least one of polyacrylate non-ionic leveling agent, polyurethane non-ionic leveling agent, methacrylic acid anion leveling agent, quaternary ammonium salt cation leveling agent, polyoxyethylene polyoxypropylene non-ionic wetting agent, sodium sulfate anion wetting agent, sodium phosphate anion wetting agent, quaternary ammonium salt type cation wetting agent.

[0046] Preferably, the photoinitiator is at least one of 2,4,6(trimethylbenzoyl) diphenylphosphine oxide (TPO), 2,4,6-trimethylbenzoyldiphenylphosphinate (abbreviated as TPO-L), 2-hydroxy-2-methyl-1-phenyl-1-propanone (photoinitiator 1173), and 1-hydroxycyclohexyl phenyl ketone (photoinitiator 184).

[0047] The fifth aspect of the present invention provides a method for preparing a coating.

[0048] A method for preparing a coating includes the following steps:

[0049] Mix the raw material components to obtain the coating.

[0050] The sixth aspect of the present invention provides an application of a coating.

[0051] An application of a coating in preparing electronic protection materials, energy storage devices, household appliances, intelligent mechanical equipment, furniture, medical devices, aerospace materials, ships, anti-corrosion materials, textile materials, or 3D printing materials.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] The present invention first uses a first polyol and a polybasic acid as raw materials, and under the atmosphere of a protective gas and in the presence of catalyst A, through a first reaction, a hyperbranched polyester prepolymer with hydroxyl groups at the ends is prepared. Further, it reacts with an isocyanate compound and a second polyol in a second reaction to obtain a hyperbranched polyurethane prepolymer with isocyanate groups at the ends. Finally, it reacts with hydroxyacrylic acid and organosiloxane in a third reaction to obtain an organosilicon-modified hyperbranched polyurethane acrylate resin as the product. The organosilicon-modified hyperbranched polyurethane acrylate resin prepared by the three-step method of the present invention has a hyperbranched structure with a three-dimensional spherical multi-branched structure, which can not only be UV-cured, but also LED-cured, and can be moisture-cured (both LED-moisture-cured and UV-moisture-cured), enabling curing in both shadow areas and shielding areas, achieving 100% curing, thorough curing, and the energy required for UV curing is greatly reduced compared with traditional UV curing (the energy required for traditional UV curing is 1200 mJ / cm 2 , and the present invention only requires 650 mJ / cm 2) It reduces energy consumption, saves energy, contains no organic solvents, has zero VOC (volatile organic compounds), a flash point above 95 °C, is safe and environmentally friendly, has a fast product curing speed (can be cured in 5 - 15 seconds), low viscosity (at 25 °C, 3000 - 5000 mPa·s), no entanglement between molecules, good flexibility, good film-forming property, strong adhesion, and excellent weather resistance. It is a high-performance environmentally friendly resin. The organosilicon-modified hyperbranched polyurethane acrylate resin provided by the present invention can be further used to prepare coatings, inks, adhesives, etc. It can be packaged immediately after brushing, effectively improving production efficiency and saving costs, and can be widely applied to various industries such as the preparation of electronic protection materials, energy storage devices, household appliances, intelligent mechanical equipment, furniture, medical devices, aerospace materials, ships, anti-corrosion materials, textile materials, 3D printing materials, etc. In addition, the raw materials used in the preparation method of the organosilicon-modified hyperbranched polyurethane acrylate resin provided by the present invention have a wide source, the synthesis process is stable, and it is convenient to realize industrial production. Description of the Drawings

[0054] Figure 1 It is the infrared spectrum of the organosilicon-modified hyperbranched polyurethane acrylate resin of Example 1 of the present invention;

[0055] Figure 2 It is the infrared spectrum of the organosilicon-modified hyperbranched polyurethane acrylate resin of Example 2 of the present invention. Detailed Embodiments

[0056] In order to make the technical solutions described in the present invention clearer and more understandable to those skilled in the art, the following examples are listed for illustration. It should be noted that the following examples do not limit the scope of protection required by the present invention.

[0057] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial channels or can be obtained by existing known methods.

[0058] Example 1

[0059] A preparation method of an LED-moisture dual-curing organosilicon-modified hyperbranched polyurethane acrylate resin, comprising the following steps:

[0060] (1) Synthesis of a hyperbranched polyester prepolymer with hydroxyl groups at the ends: First, 148 g of pentaerythritol and 106 g of 2,2-dimethylolpropionic acid (the molar ratio of pentaerythritol to 2,2-dimethylolpropionic acid is about 1.38:1) are placed in a vacuum drying oven, dried at 110 °C for 1 h to remove water, then cooled to 60 °C, 1.2 g of p-toluenesulfonic acid (catalyst A) is added, filled with N 2 protection, heated to 110 °C and reacted for 2.5 h to obtain a hyperbranched polyester prepolymer with hydroxyl groups at the ends, and cooled for standby;

[0061] (2) Synthesis of hyperbranched polyurethane prepolymer with isocyanate groups at the end: Under N 2 protection conditions, add the above-prepared hyperbranched polyester prepolymer with hydroxyl groups at the end to 68 g of 1,6-hexanediol, stir evenly, add 0.8 g of bismuth isooctanoate (catalyst), heat up to 65 °C, slowly dropwise add 196 g of hexamethylene diisocyanate, control the temperature below 85 °C, after the dropping is completed, keep the temperature at 86 °C for 1.5 h to obtain a hyperbranched polyurethane prepolymer with isocyanate groups at the end (where the molar ratio of the hyperbranched polyester prepolymer with hydroxyl groups at the end, hexamethylene diisocyanate, and 1,6-hexanediol is 4.5:1.97:1);

[0062] (3) Synthesis of organosilicon-modified hyperbranched polyurethane acrylate resin: Cool the above-prepared hyperbranched polyurethane prepolymer with isocyanate groups at the end to 60 °C, slowly dropwise add 14 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 24 g of hydroxyethyl acrylate to it (where the molar ratio of the hyperbranched polyurethane prepolymer with isocyanate groups at the end, hydroxyethyl acrylate, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is 17:3.5:1), after the dropping is completed, keep the temperature for reaction for 4.5 h, when the NCO content in the system is detected to be 4.2%, terminate the reaction to obtain an organosilicon-modified hyperbranched polyurethane acrylate resin, the product viscosity is 3620 mPa·s, the viscosity is relatively low, and it is in liquid form. The infrared spectrum of the product is as Figure 1 shown. The infrared spectrum shows that: 1690 cm -1 is the vibration peak of ester carbonyl; 1735 cm -1 is the characteristic peak of polyurethane; 2264 cm -1 is the characteristic peak of siloxane, indicating that polyurethane has been successfully prepared in the product and organosilicon modification has been carried out, and an organosilicon-modified hyperbranched polyurethane acrylate resin has been successfully prepared.

[0063] Example 2

[0064] A preparation method of an LED-moisture dual-curing organosilicon-modified hyperbranched polyurethane acrylate resin, comprising the following steps:

[0065] (1) Synthesis of hyperbranched polyester prepolymer with hydroxyl groups at the end: First, put 156 g of pentaerythritol and 113 g of 2,2-dimethylolpropionic acid (the molar ratio of pentaerythritol and 2,2-dimethylolpropionic acid is about 1.36:1) into a vacuum drying oven, dry and remove water at 110 °C for 1 h, then cool to 60 °C and add 1.2 g of p-toluenesulfonic acid (catalyst A), fill with N 2 protection, heat up to 110 °C and react for 2.5 h to obtain a hyperbranched polyester prepolymer with hydroxyl groups at the end, cool down and reserve for use;

[0066] (2) Synthesis of hyperbranched polyurethane prepolymer with isocyanate groups at the end: Under N 2 protection conditions, the above-prepared hyperbranched polyester prepolymer with hydroxyl groups at the end was added to 62 g of 1,4-butanediol and stirred evenly. 0.8 g of bismuth isooctanoate catalyst was added, and the temperature was raised to 65 °C. 286 g of isophorone diisocyanate was slowly added dropwise, with the temperature controlled below 85 °C. After the addition was completed, it was kept warm at 85 °C for 1.5 h to obtain a hyperbranched polyurethane prepolymer with isocyanate groups at the end (where the molar ratio of the hyperbranched polyester prepolymer with hydroxyl groups at the end, isophorone diisocyanate, and 1,4-butanediol is 4.5:1.87:1);

[0067] (3) Synthesis of organosilicon-modified hyperbranched polyurethane acrylate resin: The above-prepared hyperbranched polyurethane prepolymer with isocyanate groups at the end was cooled to 60 °C, and 16 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 29 g of hydroxyethyl acrylate were slowly added dropwise thereto (where the molar ratio of the hyperbranched polyurethane prepolymer with isocyanate groups at the end, hydroxyethyl acrylate, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane is 17:3.69:1). After the addition was completed, it was kept warm and reacted for 4.5 h. When the NCO content in the system was detected to be 4.7%, the reaction was terminated to obtain an organosilicon-modified hyperbranched polyurethane acrylate resin. The product viscosity was 3916 mPa·s, with a relatively low viscosity and in a liquid state. The infrared spectrum of the product is as Figure 2 shown and analyzed as follows: 1690 cm -1 is the vibration peak of the ester carbonyl group; 1735 cm -1 is the characteristic peak of polyurethane; 2264 cm -1 is the characteristic peak of siloxane, indicating that polyurethane was successfully prepared and organosilicon modification was carried out, and an organosilicon-modified hyperbranched polyurethane acrylate resin was successfully prepared.

[0068] Comparative Example 1

[0069] A preparation method of hyperbranched polyurethane acrylate includes the following steps:

[0070] (1) 55 g of pentaerythritol, 660 g of 2,2-bis(hydroxymethyl)propionic acid, 4 g of p-toluenesulfonic acid (catalyst), and 35 g of the first-generation hyperbranched polyester were added to a reaction kettle with a stirring paddle. Nitrogen was passed through, and the reaction was stirred at 140 - 160 °C under normal pressure for 2 h, and then the pressure was reduced to 0.6 kPa and reacted for 2 h; Dimethylformamide was added to the reaction kettle to dissolve, and after cooling to 50 °C, acetone was added for dilution. Recrystallization was carried out with n-hexane to obtain a white viscous substance; Acetone was repeatedly used for dissolution and n-hexane for recrystallization many times, and vacuum drying was carried out to obtain the second-generation hyperbranched polyester; The hydroxyl content of the second-generation hyperbranched polyester was obtained by hydroxyl determination as 1 mol / 100 g;

[0071] (2) 50 g of isophorone diisocyanate, 0.8 g of inhibitor hydroquinone, 0.4 g of dibutyltin dilaurate (catalyst), and 100 mL of acetone were added to a reactor, and 27 g of 2-hydroxyethyl methacrylate was dropped into it. The reaction was carried out at normal pressure for 3 h (the temperature was controlled at 35 °C) to obtain a modifier. 100 g of the prepared second-generation hyperbranched polyester, 0.5 g of dibutyltin dilaurate (catalyst), and 100 mL of tetrahydrofuran were added to the reactor and refluxed at normal pressure. After the second-generation hyperbranched polyester was completely dissolved, the above-mentioned modifier was slowly and uniformly dropped into the reactor and reacted at normal pressure for 3.5 h (the temperature was controlled at 68 °C) to obtain a transparent and clear solution. N-hexane was added to the above solution for recrystallization to obtain a white viscous substance. It was repeatedly dissolved in acetone and recrystallized with n-hexane three times, and then vacuum dried to obtain a fluffy and non-sticky white powder product, which was hyperbranched polyurethane acrylate (hyperbranched polyurethane acrylate with a modification degree of 25%).

[0072] Application Example 1

[0073] A three-proof coating, calculated by weight percentage, comprises the following raw material components:

[0074] The organosilicon-modified hyperbranched polyurethane acrylate resin prepared in Example 1, 49.3%;

[0075] Isobornyl methacrylate (reactive monomer), 21%;

[0076] Tetrahydrofurfuryl methacrylate (reactive monomer), 23%;

[0077] Defoaming agent (BYK1790), 0.5%;

[0078] Wetting and leveling agent (BYK333), 1.2%;

[0079] Photoinitiator 1173, 2.5%;

[0080] Photoinitiator 184, 2.5%.

[0081] The preparation method of the above three-proof coating comprises the following steps:

[0082] Mix the raw material components and stir and disperse for 30 min to prepare the three-proof coating.

[0083] Application Example 2

[0084] An LED-moisture dual-curing ink, calculated by weight percentage, comprises the following raw material components:

[0085] The organosilicon-modified hyperbranched polyurethane acrylate resin prepared in Example 2, 55%;

[0086] Isobornyl acrylate (reactive monomer), 17%;

[0087] Acryloylmorpholine (reactive monomer) 20.18%

[0088] Photoinitiator 1173 2.5%

[0089] Photoinitiator 184 2.5%

[0090] Organosilicon defoamer (BYK019) 0.6%

[0091] Nanoscale black toner 0.8%

[0092] Nanoscale purple toner 0.02%

[0093] Nonionic wetting and leveling agent (BYK3560) 1.4%

[0094] The preparation method of the above LED-curable ink includes the following steps:

[0095] Mix the raw material components and stir and disperse for 30 min to obtain the LED-curable ink.

[0096] Comparative application example 1

[0097] A hyperbranched polyurethane acrylate ultraviolet-curable coating includes using the hyperbranched polyurethane acrylate prepared in Comparative example 1 as one of the raw material components. The specific preparation steps are as follows:

[0098] Mix the hyperbranched polyurethane acrylate prepared in Comparative example 1 and 1,6-hexanediol diacrylate (reactive diluent) at a mass ratio of 60:40, add them to a reactor, heat and stir at 50 - 70 °C for 1 h to obtain a uniform and transparent solution. After cooling to room temperature, add 3 wt% of 2-hydroxy-2-methylpropiophenone (photoinitiator) and continue to stir for 30 min to obtain the hyperbranched polyurethane acrylate ultraviolet-curable coating.

[0099] Product effect test

[0100] I. Apply the coating prepared in Application example 1 on a circuit board for performance testing. The test method and its results are as follows:

[0101] 1. Cure with an LED (365 nm), the curing time is 10″00, the coating is surface dry and non-sticky when taken out of the oven. Under the conditions of complete darkness and an air humidity of (75 ± 10)%, it is surface dry in 18 h. The above results indicate that the coating prepared in Application example 1 can achieve dual curing of LED and moisture.

[0102] 2. Solid content: 100%. Good environmental protection performance.

[0103] 3. Adhesion: Test method: "GB / T 9286-2021 Paints and varnishes - Cross-cut test". The result is grade 0, indicating strong adhesion and no peeling phenomenon.

[0104] 4. Flexibility: Test method: "GB / T1731-2020 Determination of flexibility of paint films and putty films". The sample was evenly coated on tin foil, cured by LED, then bent 180° around a mandrel with a diameter of 0.3 cm within 1 s, and no cracks or fine cracks were observed at the bent part under a magnifying glass, indicating excellent flexibility.

[0105] 5. Water resistance: Boiled in boiling water for 4 h, no abnormality was observed on the surface of the paint film, and no abnormality was observed on the copper surface of the test board, indicating good water resistance.

[0106] 6. Mold-proof grade: Test method: IPC-TM-650 2.6.1.1. No bacterial growth was observed after 28 days of testing, and the mold-proof grade reached grade 0.

[0107] 7. Dielectric withstand voltage: Test method: IPC-TM-650 2.5.7.1. No discharge phenomenon occurred at 1500 VAC (alternating current with a voltage of 1500 volts), and the leakage current < 10 μA.

[0108] 8. Salt spray test: Test method: "GB / T 2423.17-2024 Environmental testing - Part 2: Test methods - Test Ka: Salt spray". In an environment of 5% mass fraction of NaCl solution, pH 6.7, and 35 °C, tested for 336 h, the paint film showed no change, indicating excellent salt spray resistance.

[0109] 9. Thermal shock test: Test method: IPC-TM-650 2.6.7.1A. Repeatedly tested at a high temperature of 125 °C and a low temperature of -40 °C, the high and low temperature environments were switched in 15 min, the high and low temperature switching time was 2 min, and the paint film still showed no abnormality and no cracking after 300 cycles, indicating excellent resistance to thermal shock.

[0110] 10. Acid and alkali resistance test: Immersed in 5% ammonium chloride and 3% hydrochloric acid for 500 h respectively, and the paint film showed no abnormality, indicating excellent acid and alkali resistance.

[0111] 11. Damp heat, steady state test: In an environment of temperature 85 °C and humidity 85% RH, tested for 800 h, and no abnormal phenomena such as white spots, blisters, pinholes, cracks, and wrinkles were observed on the paint film.

[0112] 12. Temperature resistance performance: The low-temperature resistance test was carried out at -40 °C for 168 h, and the paint film showed no abnormality; the high-temperature resistance test was carried out at 125 °C for 168 h, and the paint film also showed no abnormality, indicating excellent low-temperature and high-temperature resistance.

[0113] 13. Flame retardancy: Test method: UL94-2022. The flame retardancy performance is excellent, reaching V-0 level.

[0114] 14. Damp insulation resistance test: Test method: IPC-TM-650 2.6.3.4A. Test for 168 h under the conditions of temperature 85°C and humidity 85%RH, no abnormality on the board surface, and insulation resistance > 5000 MΩ.

[0115] 15. Volume resistivity: Test method: IPC-TM-650. The test results show that the volume resistivity > 1×10 13 Ω·cm.

[0116] 16. Flash point: Test method: ISO 3679, and the test result shows 96.5°C.

[0117] II. Performance test of the coating prepared in Application Example 2 applied on the circuit board. The test results are as follows:

[0118] 1. Cured by LED (365 nm), the curing time is 8″00, the surface is dry when taken out of the furnace and does not stick to hands. Under the conditions of complete darkness and air humidity (75±10)%, the surface is dry in 16 h. The above results indicate that the coating prepared in Application Example 2 can achieve dual curing of LED and moisture.

[0119] 2. Solid content: 100%. Excellent environmental protection performance.

[0120] 3. Adhesion: Test method "GB / T 9286-2021 Paints and varnishes - Cross-cut test". The result is grade 0, indicating strong adhesion and no peeling phenomenon.

[0121] 4. Water resistance: Boiled for 4 h, no abnormality on the film surface and no bleeding phenomenon.

[0122] 5. Flexibility: Test method "GB / T1731-2020 Determination of flexibility of films and putty films". The sample is evenly coated on the tin foil, cured by LED, and then bent 180° around a mandrel with a diameter of 0.3 cm within 3 s. Then, no cracks or fine cracks are observed at the bent part under a magnifying glass, indicating excellent flexibility.

[0123] 6. Salt spray test: Test method "GB / T 2423.17-2024 Environmental testing - Part 2: Test methods - Test Ka: Salt spray". In an environment of 5% NaCl, pH 6.7, and 35°C, tested for 336 h, the film has no change, and the salt spray resistance is excellent.

[0124] 7. Thermal shock test: Test method: IPC-TM-650 2.6.7.1A. Repeatedly tested at high temperature 125°C and low temperature -40°C, with a conversion time of 15 min and a high-low temperature conversion time of 2 min. After 100 cycles, the film still has no abnormality and no cracking phenomenon, indicating excellent thermal shock resistance.

[0125] 8. Acid and alkali resistance test: After being immersed in 5% ammonium chloride and 3% hydrochloric acid for 500 hours respectively, the paint film showed no abnormality and had excellent acid and alkali resistance.

[0126] 9. Temperature resistance: The paint film showed no abnormality after the low temperature resistance test was carried out at -40℃ for 168h; the paint film showed no abnormality after the high temperature resistance test was carried out at 125℃ for 168h, and the paint film showed excellent low and high temperature resistance.

[0127] 10. Flame retardancy: Test method: UL94-2022. Excellent flame retardancy, reaching V-0 level.

[0128] The same performance test method as that of Application Example 1 was used for Comparative Application Example 1, and the results are shown in the following table:

[0129] Table 1 Performance test results of coatings of Application Example 1 and Comparative Application Example 1

[0130]

[0131] From the above test results, it can be seen that the resin prepared in Example 1 of the present invention has low viscosity, is in liquid form, has good compatibility, is easy to spray, and has no splashes; and the NCO content is 4-5%, indicating that moisture curing can be achieved, solving the problem that the places that cannot be cured during UV or LED curing cannot be cured, so both the shadow area and the shielded area can be cured, achieving 100% curing; no solvent, achieving zero VOC; compared with Comparative Example 1, the resin prepared by the present invention also introduces organic siloxane, which has high chemical bond energy and strong intermolecular force, making the performance of the resin product more stable and more weather-resistant. Combined with the above test results, it can be seen that the three-proof coating of Application Example 1 made of the organosilicon-modified hyperbranched polyurethane acrylic tree of the present invention has excellent protective performance.

[0132] As can be seen from the above table, the hyperbranched polyurethane acrylate prepared in Comparative Example 1 is solid, and the coating prepared therefrom can only be UV cured, and cannot be moisture cured, so the shadow area and the shielded area cannot be cured, resulting in incomplete curing, and the solvent-based resin coating cannot achieve zero VOC, and has poor environmental performance. In addition, since the resin of Comparative Example 1 does not use organic siloxane, there is no siloxane with high chemical bond energy in the resin, and the weather resistance is poor.

Claims

1. A method for preparing a silicone-modified hyperbranched polyurethane acrylic resin, characterized in that: The steps include: (1) in a protective gas atmosphere, under the action of a catalyst A, a first polyol and a polyacid undergo a first reaction to prepare a hyperbranched polyester prepolymer containing a hydroxyl group at the end; (2) Under the action of an organic bismuth catalyst, a second reaction is carried out using the hyperbranched polyester prepolymer containing a hydroxyl group at the end, an isocyanate compound and a second polyol to obtain a hyperbranched polyurethane prepolymer containing an isocyanate group at the end; (3) The organosilicon-modified hyperbranched polyurethane acrylic resin is prepared by a third reaction of the hyperbranched polyurethane prepolymer containing an isocyanate group at the end, hydroxy acrylic acid and organosiloxane.

2. The preparation method according to claim 1, characterized in that: In step (1), the molar ratio of the first polyol to the polyacid is (1.0-1.5):

1.

3. The preparation method according to claim 1, characterized in that: In step (2), the molar ratio of the hyperbranched polyester prepolymer containing hydroxyl groups at the end, the isocyanate compound and the second polyol is (4-5):(1.8-2.5):

1.

4. The preparation method according to claim 1, characterized in that: In step (3), the molar ratio of the hyperbranched polyurethane prepolymer containing an isocyanate group at the end, hydroxy acrylic acid and organosiloxane is (15-20):(3-4):

1.

5. The preparation method according to claim 1, characterized in that: The hydroxy acrylate is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, 2-carbonyl-tetrahydrofuran-3-hydroxy-methylacrylate, 4-hydroxybutyl acrylate, hydroxyethyl methacrylate, and hydroxybutyl acrylate.

6. An organosilicon-modified hyperbranched polyurethane acrylic resin, characterized in that: The organosilicon-modified hyperbranched polyurethane acrylic resin is prepared by the preparation method of any one of claims 1 to 5, wherein the viscosity of the organosilicon-modified hyperbranched polyurethane acrylic resin at 25° C. is 3000-5000 mPa.s.

7. Use of the organosilicon-modified hyperbranched polyurethane acrylic resin according to claim 6 in the preparation of coatings, inks or adhesives.

8. A coating, characterized in that: The invention comprises the following raw material components: the organosilicon-modified hyperbranched polyurethane acrylic resin as claimed in claim 6, an active monomer, a defoamer, a wetting and leveling agent and a photoinitiator.

9. The method for preparing the coating according to claim 8, characterized in that: The steps include: The coating is prepared by mixing various raw material components.

10. Use of the coating according to claim 8 in the preparation of electronic protection materials, energy storage equipment, household appliances, intelligent mechanical equipment, furniture, medical equipment, aerospace materials, ships, anti-corrosion materials, textile materials or 3D printing materials.

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