High-gloss spray paint for motorcycles and spraying process of high-gloss spray paint

Abstract

The invention relates to the technical field of paint, and discloses high-gloss spray paint for motorcycles and a spraying process of the high-gloss spray paint. The high-gloss spray paint is prepared from the following raw materials in parts by mass: 8 to 12 parts of polyethylene glycol-polycaprolactone-acrylate, 15 to 20 parts of sulfydryl acrylate, 20 to 30 parts of acrylic resin, 6 to 10 parts of additive, 8 to 15 parts of metallic pigment, 20 to 30 parts of amino resin, 1 to 2 parts of flatting agent, 15 to 30 parts of solvent, 1 to 2 parts of solvent oil and 0.02 to 0.05 part of photoinitiator. The additive is prepared from silane modified tert-butyl methyl benzoate, double-bond modified tert-butyl methyl benzoate and an assistant cross-linking agent according to the mass ratio of (1 to 2) to (5 to 6) to 1; the preparation method of the assistant crosslinker comprises the following steps: adding 5-amino-2, 4-di-tert-butyl methyl benzoate and triphenylmethane triisocyanate into tetrahydrofuran, uniformly mixing, stirring to react for 6-8 hours at 70-90 DEG C, and removing the solvent to obtain the assistant crosslinker.

Description

Technical Field

[0001] The invention relates to the technical field of coatings and discloses a high-gloss spray paint for motorcycles and a spraying process thereof. Background Art

[0002] With the continuous development of the motorcycle market, the appearance design and decorativeness of motorcycles have gradually become one of the important factors to attract consumers. High-gloss spray paint can make the surface of the motorcycle present a brighter appearance and enhance the overall texture. Acrylic resin is a commonly used material for automotive spray paint. It has good gloss, dries quickly, and is easy to use, but there is a problem that the impact resistance needs to be improved. During the use of motorcycles, it is inevitable to encounter various complex road conditions and environments. Therefore, the impact resistance of the spray paint is required to be high. Spray paint with good impact resistance can resist external impact to a certain extent, prevent the paint film from cracking and peeling, and thus protect the vehicle body from damage. In summary, it is of great significance to study a high-gloss, high-impact-resistant spray paint and its spraying process for motorcycles. Summary of the invention

[0003] The object of the present invention is to provide a high-gloss spray paint for motorcycles and a spraying process thereof to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solution: a high-gloss spray paint for motorcycles, comprising the following raw materials, calculated by mass: 8 to 12 parts of polyethylene glycol-polycaprolactone-acrylate, 15 to 20 parts of mercapto acrylate, 20 to 30 parts of acrylic resin, 6 to 10 parts of additives, 8 to 15 parts of metallic pigments, 20 to 30 parts of amino resins, 1 to 2 parts of leveling agents, 15 to 30 parts of solvents (including butanol and ethyl acetate), 1 to 2 parts of solvent oil, and 0.02 to 0.05 parts of photoinitiator TPO.

[0005] More optimally, the additive includes silane-modified methyl tert-butyl benzoate, double-bond-modified methyl tert-butyl benzoate, and a cross-linking agent in a mass ratio of (1-2): (5-6): 1.

[0006] More optimally, the preparation of the silane-modified methyl tert-butyl benzoate includes the following steps: mixing 5-amino-2,4-di-tert-butyl benzoate, sodium hydroxide and tetrahydrofuran under nitrogen protection, adding 3-chloropropyltrimethoxysilane at 5-10° C. in an ice-water bath for a total addition time of 1.5-2 h, stirring the reaction for 2-3 h, and removing the solvent by rotary evaporation to obtain silane-modified methyl tert-butyl benzoate.

[0007] Preferably, the preparation of the double bond modified methyl tert-butylbenzoate comprises the following steps: Mix methyl 5-amino-2,4-di-tert-butylbenzoate, sodium hydroxide and tetrahydrofuran under nitrogen protection, add allyl chloroformate at 5-10 °C using an ice-water bath, with a total addition time of 1.5-2 h, stir and react for 2-3 h, and remove the solvent by rotary evaporation to obtain the double bond modified methyl tert-butylbenzoate.

[0008] Preferably, the preparation of the co-crosslinking agent comprises the following steps: Add methyl 5-amino-2,4-di-tert-butylbenzoate and triphenylmethane triisocyanate into tetrahydrofuran and mix evenly, stir and react at 70-90 °C for 6-8 h, and remove the solvent by rotary evaporation to obtain the co-crosslinking agent.

[0009] Preferably, the silane modified methyl tert-butylbenzoate comprises the following raw materials, by mass: 2.5-3 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 4-5 parts of sodium hydroxide, 100-150 parts of tetrahydrofuran, 2-3 parts of 3-chloropropyltrimethoxysilane.

[0010] Preferably, the double bond modified methyl tert-butylbenzoate comprises the following raw materials, by mass: 2.5-3 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 4-5 parts of sodium hydroxide, 100-150 parts of tetrahydrofuran, 1-2 parts of allyl chloroformate.

[0011] Preferably, the co-crosslinking agent comprises the following raw materials, by mass: 2.5-3 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 4-5 parts of triphenylmethane triisocyanate, 60-80 parts of tetrahydrofuran.

[0012] Preferably, the preparation of the mercaptoacrylate refers to the prior art and specifically comprises the following steps: Step 1: Mix thiophenol, 30% aqueous potassium hydroxide solution, 2-bromoethanol and water in a molar ratio of (0.1-0.2):(0.11-0.15):(0.1-0.2):(5-7), stir and react at 100-110 °C for 1-2 h, extract and collect the organic layer, dry and filter, and distill off the solvent to obtain an intermediate; Step 2: Dilute the thermal initiator BPO and xylene in a molar ratio of 1:5 to obtain an initiator solution; Step 3: Mix the initiator solution, the intermediate, acrylic acid and methyl methacrylate to obtain a mixed monomer; the molar ratio of the intermediate, acrylic acid and methyl methacrylate is (0.1-0.2):(0.005-0.01):(0.5-1); the addition amount of the initiator solution is 0.6-2 wt% of the total amount of the mixed monomer; Step 4: Add octadecyl mercaptan chain transfer agent to xylene and mix to obtain a primer solution with a chain transfer agent concentration of 0.1 - 0.5 wt%. At 120 - 130 °C, drop 40 - 60 wt% of the mixed monomers of the primer solution into it within 2 - 3 h, keep stirring at a constant temperature for 3 - 4 h, raise the temperature to 135 - 150 °C for reflux dehydration reaction for 1 - 2 h, and filter to obtain mercapto acrylic resin.

[0013] The spraying process of the above high - gloss paint spray includes the following steps: Put the high - gloss paint spray into a paint supply pressure tank, and directly spray it on the workpiece using a one - coat - one - bake process, with the working air pressure of 0.4 - 0.8 MPa; Let it stand at room temperature for 10 - 15 min, irradiate with ultraviolet light for 5 - 10 s, dry at 60 °C for 30 min, dry at 90 °C for 10 min, and the spraying is completed.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The composition of polyethylene glycol - polycaprolactone - acrylate, mercapto acrylate, and acrylic resin is used to replace the single acrylic resin in traditional paint sprays; among them, polyethylene glycol - polycaprolactone - acrylate contains a polyethylene glycol chain segment, which improves flexibility and polarity, thereby improving the wettability and adhesion of the paint spray to the substrate, and can better adapt to the microscopic unevenness of the substrate surface; the contained polycaprolactone chain segment can absorb and dissipate external impact energy, thereby improving the impact resistance of the material; at the same time, due to the presence of acrylate chain segments, it has good compatibility with other components. Mercapto acrylate makes the formed paint film have excellent adhesion on the metal surface, and at the same time improves the dispersion of nano - metal coatings in the paint, so the spraying of a primer is no longer required, and only one - time construction is needed; the addition amounts of the above three substances need to be controlled, otherwise the flatness of the paint film will decrease due to problems such as changes in compatibility or cross - linking degree, resulting in a decline in various performances.

[0015] The present invention also additionally adds an additive, which is obtained by mixing methyl tert - butylbenzoate modified with silane, methyl tert - butylbenzoate modified with double bonds, and a co - crosslinking agent in a certain mass ratio; due to the presence of tert - butyl, it has a certain steric hindrance, reducing the overall viscosity, thereby reducing the construction difficulty, improving the flatness, and having a certain improvement in the gloss of the paint film; among them, methyl tert - butylbenzoate modified with silane improves the dispersion of each component in the paint spray and also has an auxiliary effect on improving adhesion; methyl tert - butylbenzoate modified with double bonds, under the action of a photoinitiator, generates a cross - linking reaction with mercapto acrylate, improving the compatibility with the above - mentioned acrylate composition, and also acting as a compatibilizer to improve the overall compatibility of the additive with the acrylate composition; the co - crosslinking agent contains an isocyanate group, which plays a role in increasing the cross - linking degree of the paint spray, forming a network structure, and improving the impact resistance; the addition amounts of each component in this additive and the addition amount of this additive also need to be controlled to ensure that the performance will not decline due to excessive cross - linking. Detailed implementation mode

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0017] It should be noted that there are no special restrictions on the purchasing manufacturers of all raw materials involved in the present invention. Exemplarily, they include: ethanol (CAS: 64-17-5); polyethylene glycol-polycaprolactone-acrylate (PolySciTech PST-Al126); acrylic resin (DSM CR201-65); metallic pigment (Bote Company nano metallic paint 5000); amino resin (butylated amino resin allnex CYMEL1158); leveling agent (Efka AFCONA3777); solvent naphtha (Mingwei S-100 solvent naphtha); benzenethiol (CAS: 108-98-5); 30% aqueous potassium hydroxide solution (Nanjing Chemical Reagent Co., Ltd.); thermal initiator (BPO benzoyl peroxide); photoinitiator (TPO, CAS: 75980-60-8) octadecyl mercaptan (CAS: 112-55-0); methyl 5-amino-2,4-di-tert-butylbenzoate (CAS: 1182822-31-6); 3-chloropropyltrimethoxysilane (CAS: 2530-87-2); allyl chloroformate (CAS: 2937-50-0); triphenylmethane triisocyanate (4,4ˊ,4〞-triphenylmethane triisocyanate, CAS: 2422-91-5); Unless otherwise specified, the following are all in parts by mass or mass ratio; Preparation of mercaptoacrylate: Mix benzenethiol, 30% aqueous potassium hydroxide solution, 2-bromoethanol and water in a molar ratio of 0.1:0.15:0.15:6, stir and react at 110 °C for 1 h, extract twice with ethyl acetate, collect the organic layer, dry with anhydrous magnesium sulfate, filter, and distill off the solvent to obtain an intermediate; mix the initiator BPO and xylene in a molar ratio of 1:5 to obtain an initiator solution; mix the initiator solution, the intermediate, acrylic acid, and methyl methacrylate to obtain a mixed monomer; the molar ratio of the intermediate, acrylic acid, and methyl methacrylate is 0.15:0.01:0.8; the addition amount of the initiator solution is 1 wt% of the total amount of the mixed monomer; add octadecyl mercaptan chain transfer agent to xylene and mix to obtain a primer solution with a chain transfer agent concentration of 0.4 wt%; at 120 °C, drop 50 wt% of the primer solution mass of the mixed monomer in 3 h, keep stirring for 4 h, raise the temperature to 145 °C for reflux dehydration reaction for 2 h, and filter to obtain mercaptoacrylate resin; Example 1: S1: Mix 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 3 parts of 3-chloropropyltrimethoxysilane at 5 °C using an ice-water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain silane-modified methyl tert-butylbenzoate; S2: Mix 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 2 parts of allyl chloroformate at 5 °C using an ice-water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain double-bond-modified methyl tert-butylbenzoate; S3: Add 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate and 5 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran and mix evenly. Stir and react at 80 °C for 8 h, and remove the solvent by rotary evaporation to obtain a co-crosslinking agent; S4: Mix silane-modified methyl tert-butylbenzoate, double-bond-modified methyl tert-butylbenzoate, and the co-crosslinking agent in a mass ratio of 1.5:6:1 to obtain an additive: S5: Take 10 parts of polyethylene glycol-polycaprolactone-acrylate, 20 parts of mercaptoacrylate, 25 parts of acrylic resin, 8.5 parts of the additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent oil, and 0.04 part of photoinitiator and mix to obtain a high-gloss spray paint.

[0018] Example 2: S1: Mix 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 2 parts of 3-chloropropyltrimethoxysilane at 5 °C using an ice-water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain silane-modified methyl tert-butylbenzoate; S2: Mix 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 1 part of allyl chloroformate at 5 °C using an ice-water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain double-bond-modified methyl tert-butylbenzoate; S3: Add 2.5 parts of methyl 5-amino-2,4-di-tert-butylbenzoate and 4 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran and mix evenly. Stir and react at 90 °C for 6 h, and remove the solvent by rotary evaporation to obtain a co-crosslinking agent; S4: Mix silane-modified methyl tert-butylbenzoate, double-bond-modified methyl tert-butylbenzoate, and the co-crosslinking agent in a mass ratio of 1:5:1 to obtain an additive: S5: Take 12 parts of polyethylene glycol - polycaprolactone - acrylate, 15 parts of mercaptoacrylate, 28 parts of acrylic resin, 7 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 2 parts of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent naphtha, and 0.04 part of photoinitiator, mix them to obtain a high - gloss spray paint.

[0019] Example 3: S1: Mix 3 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 3 parts of 3 - chloropropyltrimethoxysilane at 5°C using an ice - water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain silane - modified methyl tert - butylbenzoate. S2: Mix 3 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 2 parts of allyl chloroformate at 5°C using an ice - water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain double - bond - modified methyl tert - butylbenzoate. S3: Add 3 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate and 5 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran and mix evenly. Stir and react at 70°C for 8 h, and remove the solvent by rotary evaporation to obtain a co - crosslinking agent. S4: Mix silane - modified methyl tert - butylbenzoate, double - bond - modified methyl tert - butylbenzoate, and the co - crosslinking agent in a mass ratio of 2:6:1 to obtain an additive. S5: Take 8 parts of polyethylene glycol - polycaprolactone - acrylate, 17 parts of mercaptoacrylate, 30 parts of acrylic resin, 9 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 5 parts of butanol, 15 parts of ethyl acetate, 1 part of solvent naphtha, and 0.04 part of photoinitiator, mix them to obtain a high - gloss spray paint.

[0020] Comparative Example 1 (without adding polyethylene glycol - polycaprolactone - acrylate, and the remaining method steps are the same as those in Example 1): S1: Mix 2.5 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 3 parts of 3 - chloropropyltrimethoxysilane at 5°C using an ice - water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain silane - modified methyl tert - butylbenzoate. S2: Mix 2.5 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 2 parts of allyl chloroformate at 5°C using an ice - water bath. The total addition time is 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain double - bond - modified methyl tert - butylbenzoate. S3: Add 2.5 parts of methyl 5-amino-2,4-ditert-butylbenzoate and 5 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran, mix evenly, stir and react at 80 °C for 8 h, and remove the solvent by rotary evaporation to obtain a co-crosslinking agent; S4: Mix methyl 5-amino-2,4-ditert-butylbenzoate modified with silane, methyl 5-amino-2,4-ditert-butylbenzoate modified with double bond, and the co-crosslinking agent in a mass ratio of 1.5:6:1 to obtain an additive; S5: Take 30 parts of mercaptoacrylate, 25 parts of acrylic resin, 8.5 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent oil, and 0.04 part of photoinitiator, mix them to obtain a high-gloss spray paint.

[0021] Comparative Example 2 (reduce the amount of mercaptoacrylate added, increase the amount of polyethylene glycol-polycaprolactone-acrylate added, and the other method steps are the same as those in Example 1): S1: Mix 2.5 parts of methyl 5-amino-2,4-ditert-butylbenzoate, 5 parts of sodium hydroxide and 120 parts of tetrahydrofuran under nitrogen protection, add 3 parts of 3-chloropropyltrimethoxysilane at 5 °C using an ice-water bath, with a total addition time of 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain methyl 5-amino-2,4-ditert-butylbenzoate modified with silane; S2: Mix 2.5 parts of methyl 5-amino-2,4-ditert-butylbenzoate, 5 parts of sodium hydroxide and 120 parts of tetrahydrofuran under nitrogen protection, add 2 parts of allyl chloroformate at 5 °C using an ice-water bath, with a total addition time of 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain methyl 5-amino-2,4-ditert-butylbenzoate modified with double bond; S3: Add 2.5 parts of methyl 5-amino-2,4-ditert-butylbenzoate and 5 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran, mix evenly, stir and react at 80 °C for 8 h, and remove the solvent by rotary evaporation to obtain a co-crosslinking agent; S4: Mix methyl 5-amino-2,4-ditert-butylbenzoate modified with silane, methyl 5-amino-2,4-ditert-butylbenzoate modified with double bond, and the co-crosslinking agent in a mass ratio of 1.5:6:1 to obtain an additive; S5: Take 20 parts of polyethylene glycol-polycaprolactone-acrylate, 10 parts of mercaptoacrylate, 25 parts of acrylic resin, 8.5 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent oil, and 0.04 part of photoinitiator, mix them to obtain a high-gloss spray paint.

[0022] Comparative Example 3 (replace the additive with methyl 5-amino-2,4-ditert-butylbenzoate modified with silane, and the other method steps are the same as those in Example 1): S1: Mix 2.5 parts of methyl 5-amino-2,4-ditert-butylbenzoate, 5 parts of sodium hydroxide and 120 parts of tetrahydrofuran under nitrogen protection, add 3 parts of 3-chloropropyltrimethoxysilane at 5 °C using an ice-water bath, with a total addition time of 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain an additive; S2: Take 10 parts of polyethylene glycol - polycaprolactone - acrylate, 20 parts of mercaptoacrylate, 25 parts of acrylic resin, 8.5 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent oil, and 0.04 part of photoinitiator, mix them to obtain a high - gloss spray paint.

[0023] Comparative Example 4 (increasing the dosage of additive, and the other method steps are the same as those in Example 1): S1: Mix 2.5 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 3 parts of 3 - chloropropyltrimethoxysilane at 5°C using an ice - water bath, with a total addition time of 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain silane - modified methyl tert - butylbenzoate. S2: Mix 2.5 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate, 5 parts of sodium hydroxide, and 120 parts of tetrahydrofuran under nitrogen protection. Add 2 parts of allyl chloroformate at 5°C using an ice - water bath, with a total addition time of 2 h, stir and react for 3 h, and remove the solvent by rotary evaporation to obtain double - bond - modified methyl tert - butylbenzoate. S3: Add 2.5 parts of methyl 5 - amino - 2,4 - di - tert - butylbenzoate and 5 parts of triphenylmethane triisocyanate to 80 parts of tetrahydrofuran, mix evenly, stir and react at 80°C for 8 h, and remove the solvent by rotary evaporation to obtain a co - crosslinking agent. S4: Mix silane - modified methyl tert - butylbenzoate, double - bond - modified methyl tert - butylbenzoate, and the co - crosslinking agent in a mass ratio of 1.5:6:1 to obtain an additive. S5: Take 10 parts of polyethylene glycol - polycaprolactone - acrylate, 20 parts of mercaptoacrylate, 25 parts of acrylic resin, 12.75 parts of additive, 15 parts of metallic pigment, 25 parts of amino resin, 1 part of leveling agent, 8 parts of butanol, 12 parts of ethyl acetate, 1 part of solvent oil, and 0.04 part of photoinitiator, mix them to obtain a high - gloss spray paint.

[0024] Performance test: Take the high - gloss spray paints prepared in Examples 1 - 3 and Comparative Examples 1 - 4, put them into a paint - feeding pressure tank, and directly spray them on the surface - cleaned 2024 - T3 aluminum plate using a one - coat - one - bake process. The spraying thickness is 30 μm, the working air pressure is 0.8 MPa, let it stand at room temperature for 15 min, irradiate with ultraviolet light for 10 s, dry at 60°C for 30 min, and dry at 90°C for 10 min to obtain samples; (1) Test the glossiness with reference to the standard GB / T9754; (2) Test the impact resistance with reference to GB / T1732; see Table 1 for details. Table 1:

[0025] Conclusion: In Comparative Example 1, polyethylene glycol-polycaprolactone-acrylate was not added, resulting in a decrease in both adhesion and impact resistance, and the gloss was also inferior to that of the examples; in Comparative Example 2, the amount of mercaptoacrylate added was reduced and the amount of polyethylene glycol-polycaprolactone-acrylate added was increased, and due to factors such as crosslinking degree and compatibility, the performance decreased; in Comparative Example 3, methyl tert-butylbenzoate modified with silane was used to replace the additive, that is, there was no double-bond modified methyl tert-butylbenzoate and co-crosslinking agent, and the performance decreased; in Comparative Example 4, the amount of additive was increased and the performance decreased. From this, it can be seen that the control of the dosage is also of great significance; in summary, the high-gloss paint prepared by this solution has good adhesion, high gloss and good impact resistance.

[0026] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high gloss spray paint for motorcycles, characterized in that: The invention comprises the following raw materials, calculated by weight: 8 to 12 parts of polyethylene glycol-polycaprolactone-acrylate, 15 to 20 parts of mercapto acrylate, 20 to 30 parts of acrylic resin, 6 to 10 parts of additives, 8 to 15 parts of metallic pigments, 20 to 30 parts of amino resins, 1 to 2 parts of leveling agents, 15 to 30 parts of solvents, 1 to 2 parts of solvent oils, and 0.02 to 0.05 parts of photoinitiators.

2. The high gloss spray paint for motorcycles according to claim 1, characterized in that: The additives include silane-modified tert-butyl benzoic acid methyl ester, double-bond-modified tert-butyl benzoic acid methyl ester, and a cross-linking agent in a mass ratio of (1-2): (5-6):

1.

3. The high gloss spray paint for motorcycles according to claim 2, characterized in that: The preparation of the silane-modified methyl tert-butylbenzoate comprises the following steps: mixing 5-amino-2,4-di-tert-butylbenzoic acid methyl ester, sodium hydroxide and tetrahydrofuran under nitrogen protection, adding 3-chloropropyltrimethoxysilane at 5-10° C. in an ice-water bath for a total adding time of 1.5-2 hours, stirring for reaction for 2-3 hours, and removing the solvent by rotary evaporation to obtain the silane-modified methyl tert-butylbenzoate.

4. The high gloss spray paint for motorcycles according to claim 2, characterized in that: The preparation of the double-bond modified methyl tert-butyl benzoate comprises the following steps: mixing 5-amino-2,4-di-tert-butyl benzoate, sodium hydroxide and tetrahydrofuran under nitrogen protection, adding allyl chloroformate at 5-10° C. in an ice-water bath for a total adding time of 1.5-2 hours, stirring for reaction for 2-3 hours, and removing the solvent by rotary evaporation to obtain the double-bond modified methyl tert-butyl benzoate.

5. The high gloss spray paint for motorcycles according to claim 2, characterized in that: The preparation of the auxiliary cross-linking agent comprises the following steps: adding 5-amino-2,4-di-tert-butylbenzoic acid methyl ester and triphenylmethane triisocyanate into tetrahydrofuran and mixing them evenly, stirring and reacting at 70-90° C. for 6-8 hours, and removing the solvent by rotary evaporation to obtain the auxiliary cross-linking agent.

6. The high gloss spray paint for motorcycles according to claim 3, characterized in that: The silane-modified methyl tert-butylbenzoate comprises the following raw materials, in parts by mass: 2.5-3 parts of 5-amino-2,4-di-tert-butylbenzoic acid methyl ester, 4-5 parts of sodium hydroxide, 100-150 parts of tetrahydrofuran, and 2-3 parts of 3-chloropropyltrimethoxysilane.

7. The high gloss spray paint for motorcycles according to claim 4, characterized in that: The double-bond modified methyl tert-butylbenzoate comprises the following raw materials, calculated by mass: 2.5-3 parts of 5-amino-2,4-di-tert-butylbenzoic acid methyl ester, 4-5 parts of sodium hydroxide, 100-150 parts of tetrahydrofuran, and 1-2 parts of allyl chloroformate.

8. The high gloss spray paint for motorcycles according to claim 5, characterized in that: The auxiliary cross-linking agent comprises the following raw materials, calculated by weight: 2.5 to 3 parts of 5-amino-2,4-di-tert-butylbenzoic acid methyl ester, 4 to 5 parts of triphenylmethane triisocyanate, and 60 to 80 parts of tetrahydrofuran.

9. The high gloss spray paint for motorcycles according to claim 1, characterized in that: The preparation of the mercaptoacrylate comprises the following steps: step 1: mixing thiophenol, potassium hydroxide aqueous solution, 2-bromoethanol and water in a molar ratio of (0.1-0.2): (0.11-0.15): (0.1-0.2): (5-7), stirring at 100-110° C. for 1-2 hours, extracting and collecting an organic layer, drying and filtering, and distilling off the solvent to obtain an intermediate; Step 2: Mix and dilute the thermal initiator and xylene at a molar ratio of 1:5 to obtain an initiator solution; Step 3: Mix the initiator solution, the intermediate, acrylic acid and methyl methacrylate to obtain a mixed monomer; the molar ratio of the intermediate, acrylic acid and methyl methacrylate is (0.1-0.2): (0.005-0.01): (0.5-1); the amount of the initiator solution added is 0.6-2wt% of the total amount of the mixed monomer; Step 4: Add octadecyl mercaptan chain transfer agent to xylene and mix to obtain a primer with a chain transfer agent concentration of 0.1-0.5wt%; add 40-60wt% of the mixed monomers of the primer at 120-130°C over 2-3h, keep warm and stir for 3-4h, raise the temperature to 135-150°C, reflux and dehydrate for 1-2h, and filter to obtain mercapto acrylic resin.

10. A high gloss spraying process for motorcycles, characterized in that: The high gloss spray paint according to any one of claims 1 to 9 is placed in a paint delivery pressure tank, and sprayed directly on the workpiece using a one-coat-one-bake process with a working pressure of 0.4 to 0.8 MPa; the workpiece is allowed to stand at room temperature for 10 to 15 minutes, and then exposed to ultraviolet light and dried by baking to complete the spraying.

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