CN113683714B - Thioether type naphthalimide derivative photoinitiator containing hydrogen donor and suitable for UV-LED aerobic light curing - Google Patents

Abstract

The invention discloses a thioether type naphthalimide derivative photoinitiator containing a hydrogen donor, which is suitable for UV-LED aerobic light curing, relates to the field of photosensitive polymers, and is provided based on the problem that the initiation performance of the existing photoinitiator is poor under the irradiation of a UV-LED light source and in the presence of oxygen; the invention prepares a photoinitiator containing hydrogen donor thioether type naphthalimide derivative, and provides a preparation method and application thereof in a photocuring system; the invention has the beneficial effects that: (1) the ultraviolet absorption wavelength of the photoinitiator prepared by the invention is obviously prolonged, and the photoinitiator has better ultraviolet absorption capacity within the wavelength range of an LED light source. (2) The photoinitiator prepared by the invention has obvious antioxidant polymerization inhibition effect. (3) The migration stability of the photoinitiator prepared by the invention is obviously improved.

Description

A hydrogen-donor-containing sulfide-type naphthalene imide derivative suitable for UV-LED aerobic photocuring biological photoinitiator

technical field

The invention relates to the field of photosensitive polymers, in particular to a preparation method and application of a hydrogen donor-containing sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring.

Background technique

UV light curing technology is a new technology that came out in the middle of the 20th century. It uses ultraviolet light (with a wavelength of 200-400nm) as the energy source to trigger the rapid transformation of chemically reactive liquid substances into solids. Compared with the traditional thermal curing technology, it has the advantages of fast speed, high efficiency, less pollution and low cost, and is a rapidly developing "green" new technology. UV photocurable products are composed of three parts, namely photoinitiator, photocurable resin and monomer (also known as reactive diluent).

Ultraviolet light-emitting diode (UV-LED) is a semiconductor electronic device. UV-LED equipment can convert electrical energy into optical radiation. As a radiation equipment, UV-LED has been widely used in radiation curing reaction and other fields. Compared with traditional UV light sources, UV-LED light sources have the following characteristics: (1) It can emit almost monochromatic light, and its spectral line width is very narrow (5-20nm); (2) The luminous output is almost 100% (3) low energy consumption; (4) no ozone; (5) no ultraviolet radiation; (6) low heat generation; (7) low operating costs; (8) long service life; (9) safe and simple operation ; (10) compact design, easy to carry. The use of UV-LED light sources with low energy consumption and high safety performance in industry can not only ensure the safety of personnel but also reduce costs. In view of its advanced, economical and environmentally friendly characteristics, UV-LED has a good development prospect and is applied to some potential new fields.

UV-LED light curing technology is currently limited by the absorption wavelength of the photoinitiator and the problem of oxygen inhibition during the curing process. Most of the reported or commercialized photoinitiators have poor light absorption wavelengths above 365nm. Under the irradiation of UV-LED light source, the initiation performance of these photoinitiators is poor. In addition, these commercial photoinitiators are sensitive to oxygen and must be strictly deoxygenated during use. These two points severely limit the development and promotion of UV-LED photocuring technology.

SUMMARY OF THE INVENTION

The invention provides a hydrogen donor-containing sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring and a preparation method thereof. The photoinitiator can well initiate photopolymerization of monomers to form a polymer film in an environment where oxygen exists, and has low mobility. The present invention prepares a series of hydrogen-donor-containing sulfide-type naphthalimide derivative photoinitiators suitable for UV-LED aerobic photocuring through extensive and in-depth research and molecular design.

To achieve the above object, the present invention adopts the following technical solutions:

1. A hydrogen donor sulfide type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring is characterized in that: the general chemical structure formula of the photoinitiator is as follows:

Wherein the value range of n is 1～10; R ₁ is selected from C ₃ -C ₂₀ aliphatic alkyl, hydroxyl, vinyl, propenyl, methyl, ethyl, alkoxy, halogen atom, aralkyl or benzene Base _; R2 is selected from carboxyl, benzoyl, acetyl, acryloyl, methoxy, ethoxy, nitro.

2. The method according to item 1, characterized in that: the value range of n is 1-5; R ₁ is selected from vinyl and methyl; R ₂ is selected from methoxy.

3. The method according to item 2, characterized in that: the value of n is 1.

4. A method for preparing a hydrogen donor sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring described in item 1, characterized in that: its general synthesis process is as follows Shown:

5. according to the method described in item 4, it is characterized in that: the preparation method that is applicable to the hydrogen donor sulfide type naphthalimide derivative photoinitiator that is applicable to UV-LED aerobic photocuring comprises the following steps:

(1) In the step a, the primary amine and 4-bromo-1,8-naphthalene dicarboxylic anhydride are added to the reaction vessel, and reacted at 60-100°C for 24 hours; after the reaction is completed, cool, and then the crude product Washed several times with absolute ethanol to obtain brown-red solid intermediate A;

(2) In the step a, the intermediate product A and the acid chloride are added to the reaction vessel, an anhydrous organic solvent is added, and the reaction is carried out at 0-5° C. for 6 h; after the reaction is completed, the anhydrous solvent is distilled off under reduced pressure to obtain the crude product , and then purify the crude product with a chromatographic column to obtain a pale yellow solid intermediate B;

(3) In the step c, add benzylmercaptan, acetic anhydride and catalyst into the reactor and heat to reflux for 12h and stir; concentrated carbonate aqueous solution, and then washed with deionized water, the organic layer was dried with a desiccant, filtered, and the solvent was distilled off under reduced pressure to obtain a crude product, and then the crude product was purified by a chromatographic column to obtain a colorless liquid intermediate product C;

(4) In the step d, mix the intermediate product B prepared in step b, the intermediate product C prepared in step c, the palladium catalyst, the iron complex and the alkali, and add an appropriate amount of organic solvent 1 and organic solvent 2 , reacted for 24 hours in a nitrogen atmosphere and at 80-120 °C; after the reaction was completed, cooled, poured the reaction solution into an appropriate amount of saturated saline solution to wash, and then extracted with dichloromethane, combined the organic phases, and washed the organic layer with saturated brine. The organic layer was dried with a desiccant, filtered, and the solvent was distilled off under reduced pressure to obtain a crude product, and then the crude product was purified by a chromatographic column to obtain the final product.

6. The method according to item 5, characterized in that: in the step a, the number of moles of the primary amine is 1 to 10 times that of 4-bromo-1,8-naphthalic anhydride; the reaction temperature It is 70-90°C.

7. The method according to item 6, characterized in that: in the step a, the number of moles of the primary amine is 3 to 6 times that of 4-bromo-1,8-naphthalene dicarboxylic anhydride.

8. The method according to item 7, characterized in that: in the step a, the number of moles of the primary amine is 5 times that of 4-bromo-1,8-naphthalene dicarboxylic anhydride; the reaction temperature is 85°C .

9. The method according to item 5, characterized in that: in the step b, the acid chloride is selected from acetyl chloride, acryloyl chloride, methacryloyl chloride, benzoyl chloride, terephthaloyl chloride, oxalyl chloride, para One or more of tosyl chloride; the number of moles of the acid chloride is 1 to 6 times that of the intermediate product A; the organic base is selected from triethylamine, diethylamine, 4-dimethylaminopyridine, pyridine, One or more of 3-picoline and 2-picoline; the number of moles of the organic base is 1 to 7 times that of the intermediate product A; the anhydrous organic solvent is selected from anhydrous dichloromethane, One or more of absolute ethanol, anhydrous petroleum ether, anhydrous acetone, anhydrous toluene, and anhydrous tetrahydrofuran; the reaction temperature is 0-2°C.

10. The method according to item 9, characterized in that: in the step b, the acid chloride is selected from acetyl chloride and acryloyl chloride; the number of moles of the acid chloride is 2 to 4 times that of the intermediate product A; the organic The base is selected from triethylamine; the number of moles of the organic base is 2 to 5 times that of the intermediate product A; the anhydrous organic solvent is selected from anhydrous dichloromethane.

11. The method according to item 10, characterized in that: in the step b, the number of moles of the acid chloride is 3 times that of the intermediate product A; the number of moles of the organic base is 4 times that of the intermediate product A; The reaction temperature is 0°C.

12. The method according to item 5, characterized in that: in the step c, the number of moles of the acetic anhydride is 0.5 to 4.5 times that of benzyl mercaptan; the catalyst is ferric chloride, ferrous chloride, One or more of copper chloride, cuprous chloride, nickel chloride, aluminum chloride, sodium nitrate, potassium nitrate, and magnesium nitrate; the molar number of the catalyst is 0.001 to 0.020 times that of benzyl mercaptan; Described carbonate aqueous solution is one or more in sodium carbonate aqueous solution, potassium carbonate aqueous solution, ammonium carbonate aqueous solution, sodium bicarbonate aqueous solution, potassium bicarbonate aqueous solution, ammonium bicarbonate aqueous solution; The concentration of described carbonate aqueous solution is 1 %~25%.

13. The method according to item 12, characterized in that: in the step c, the number of moles of the acetic anhydride is 1.5 to 2.5 times that of benzylmercaptan; the catalyst is nickel chloride; the moles of the catalyst The number is 0.008-0.012 times that of benzyl mercaptan; the carbonate aqueous solution is sodium bicarbonate aqueous solution; the concentration of the carbonate aqueous solution is 9%-12%.

14. according to the described method of item 13, it is characterized in that: in described step c, the number of moles of described acetic anhydride is 2.0 times of benzylmercaptan; The number of moles of described catalyst is 0.010 times of benzylmercaptan; The concentration of the carbonate aqueous solution is 10%.

15. The method according to item 5, characterized in that: in the step d, the palladium catalyst is selected from bis(dibenzylideneacetone)palladium, tris(dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, bis(dibenzylideneacetone) One of triphenylphosphino)palladium acetate, bis(di-tert-butylphenylphosphine)palladium dichloride, bis(3,5,3',5'-dimethoxydibenzylideneacetone)palladium or more; the iron complex is selected from 1,1'-bis(diphenylphosphino)ferrocene, 1,1-bisdiphenylphosphinoferrocene nickel chloride, (S,S)- One of (-)-2,2'-bis[-(N,N-dimethylamino)(phenyl)methyl]-1,1'-bis(diphenylphosphino)ferrocene or Multiple; the inorganic base is selected from one or more of sodium hydroxide, sodium hydroxide, calcium hydroxide, aluminum hydroxide, lithium hydroxide, magnesium hydroxide, zinc hydroxide, anhydrous tripotassium phosphate; The number of moles of the palladium catalyst is 0.1 to 0.8 times that of the intermediate product B; the number of moles of the iron complex is 0.10 to 0.20 times that of the intermediate product B; the number of moles of the inorganic base is 1.0 to 5.0 times that of the intermediate product B times; the number of moles of the intermediate product C is 1 to 5 times that of the intermediate product B; the reaction temperature is 90 to 115°C; the organic solvent 1 is the same or different from the organic solvent 2, and is independently selected from toluene , dichloromethane, methanol, acetone, petroleum ether, ethyl acetate, ethanol; the volume of the organic solvent 1 is 1 to 6 times that of the organic solvent 2; the organic solvent 1 and the organic solvent 2. The total volume is 1-24mL; the saturated salt solution is selected from one of saturated ammonium chloride solution, saturated ammonium sulfate solution, saturated magnesium chloride solution, saturated sodium sulfate solution, saturated potassium chloride solution, and saturated potassium nitrate solution or more.

16. The method according to item 15, characterized in that: in the step d, the palladium catalyst is selected from bis(dibenzylideneacetone) palladium; the iron complex is selected from 1,1'-bis (diphenylphosphino) ferrocene; the inorganic base is selected from anhydrous tripotassium phosphate; the molar number of the palladium catalyst is 0.3 to 0.7 times that of the intermediate product B; the molar number of the iron complex is intermediate 0.12 to 0.18 times that of product B; the number of moles of the inorganic base is 2.0 to 3.0 times that of the intermediate product B; the number of moles of the intermediate product C is 2 to 3 times that of the intermediate product B; the reaction temperature is 110°C The organic solvent 1 is toluene; the organic solvent 2 is acetone; the volume of the organic solvent 1 is 2 to 4 times that of the organic solvent 2; the total volume of the organic solvent 1 and the organic solvent 2 is 5 to 17 mL ; The saturated salt solution is a saturated ammonium chloride solution.

17. The method according to item 16, characterized in that: in the step d, the number of moles of the palladium catalyst is 0.6 times that of the intermediate product B; the number of moles of the iron complex is 0.14 times that of the intermediate product B ; The number of moles of the inorganic base is 2.4 times that of the intermediate product B; the number of moles of the intermediate product C is 3 times that of the intermediate product B; the volume of the organic solvent 1 is 2 times that of the organic solvent 2; the organic solvent The total volume of solvent 1 and organic solvent 2 is 12 mL.

18. The method according to item 5, characterized in that: in the step c and step d, the desiccant is selected from anhydrous magnesium sulfate, anhydrous sodium sulfate, anhydrous magnesium chloride, anhydrous calcium chloride one or more.

19. The method according to item 18, characterized in that: in the step b and step c, the desiccant is anhydrous sodium sulfate.

20. A free radical photocurable composition, comprising a hydrogen donor sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring described in item 1; the composition It contains 0.1%-5% of the hydrogen-donor-containing thioether-type naphthalimide derivative photoinitiator and 95%-99.9% of photocurable resin or monomer, based on the total weight of the composition.

21. According to the composition described in item 20, it is characterized in that: the photocurable resin is selected from epoxy (meth)acrylic resin, polyurethane (meth)acrylic resin, polyester (meth)acrylic resin, polyester One or more of ether (meth)acrylic resins, acrylated poly(meth)acrylic resins; the monomer is one or more of monofunctional or polyfunctional (meth)acrylates Various.

In the following description of the present invention, unless otherwise explicitly stated, the numerical values in the present application can be regarded as modified by the word "about". However, the inventors have reported the numerical values in the examples as precisely as possible although some errors inevitably included.

In this application, unless expressly excluded, specific or preferred embodiments of the invention may be combined. In addition, each element of the embodiment of the present application is a specific preferred selection of the corresponding high-level technical features. If the overriding technical features can be combined with other overriding features, the elements of the embodiments, that is, the specific preferred options, can also be combined with the other overriding features. These combinations should be regarded as a part of the original content of this application.

The present invention also provides the application of the above-mentioned photoinitiator in a photocuring system.

The beneficial effects of the present invention are: compared with traditional photoinitiators, the ultraviolet absorption wavelength of the photoinitiator prepared by the present invention is obviously extended, and its performance of anti-oxygen and polymerization inhibition is obviously improved, and it can be used in the presence of UV-LED light source and oxygen. Under certain conditions, it has high photocuring efficiency, which is beneficial to the development of UV-LED photocuring industry; it has low mobility, which is conducive to the development of the food packaging industry.

Description of drawings

Fig. 1 is the photoinitiation mechanism diagram that contains hydrogen donor sulfide type naphthalimide derivative photoinitiator that the present invention provides;

Fig. 2 is the anti-oxygen inhibition mechanism diagram of the hydrogen donor sulfide type naphthalimide derivatives photoinitiator containing hydrogen provided by the present invention;

Fig. 3 is the ultraviolet absorption spectrogram of the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives prepared in Example 1-2 of the present invention;

Fig. 4 is the real-time infrared images of the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives prepared in Example 1-2 of the present invention and photoinitiator 2959, 184, 1173 in the presence of oxygen to initiate monomer polymerization spectrogram;

Fig. 5 is the migration stability diagram in the polymer film of the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives prepared in Example 1-2 of the present invention;

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

The above-mentioned hydrogen donor-containing thioether-type naphthalimide derivative photoinitiator can be broken in two ways under the irradiation of a 405nm LED light source to generate free radicals with initiating activity. As shown in Figure 1, under light, the photoinitiator first reaches the excited singlet state, and then a small number of molecules in the excited state undergo cleavage mode 1 to generate p-methoxybenzyl radicals and arylsulfur radicals; while most Excited molecules undergo cleavage method 2 to generate p-methoxybenzylsulfide radicals and aryl radicals, thereby initiating the polymerization of monomer 1,6-hexanediol diacrylate (HDDA) to form a polymer film. The above-mentioned photoinitiator molecules containing hydrogen donor thioether type naphthalimide derivatives can still effectively initiate the monomer polymerization process in the environment where oxygen exists. The heavy state can undergo a hydrogen abstraction reaction to generate an alkyl radical, and then the alkyl radical combines with oxygen to generate a peroxyl radical with a stable six-membered ring structure. However, this peroxyl radical cannot initiate the polymerization of the monomer ; Subsequently, the peroxyl radical generates new alkyl radicals to initiate the polymerization of monomers through intramolecular hydrogen extraction (mode 1) and intermolecular hydrogen extraction (mode 2), thus endowing this Hydrogen donor thioether-type naphthalimide derivative photoinitiator reduces the performance of oxygen inhibition.

The experimental materials and reagents used in the following examples can be obtained from commercial sources unless otherwise specified.

[Example 1]

Photoinitiator NABS-HD-1 has the following structural formula:

Its preparation method comprises the following steps:

(a) 4-bromo-1,8-naphthalic anhydride (7.20g, 0.026mol), diglycolamine (13.67g, 0.13mol) and 100mL absolute ethanol were added to a 250mL single-necked flask, under nitrogen protection After the reaction, the reaction liquid was cooled to room temperature and filtered to obtain the crude product. The filter residue was washed with absolute ethanol several times, and the intermediate product was obtained after vacuum drying, which was named BHBD.

(b) BHBD (5.83g, 16mmol), triethylamine (6.48g, 64mmol) and 150mL of anhydrous dichloromethane synthesized in Example 1 were added to a 250mL single-necked flask, and acetyl chloride (3.77g, 48mmol) was dissolved in 20mL of anhydrous dichloromethane, added dropwise into a single-necked flask in an ice-water bath at 0°C, and stirred for 6h; after the reaction was completed, the solvent was distilled off under reduced pressure to obtain a crude product, which was then purified by a chromatographic column , to obtain an intermediate product named BDBIEA.

(c) Add p-methoxybenzylmercaptan (3.09g, 0.02mol), acetic anhydride (4.08g, 0.04mol) and anhydrous nickel chloride (259mg, 2mmol) into a 50mL single-necked flask and heat to 75°C , stirred for 4h. After the reaction is over, add an appropriate amount of deionized water to the reactor, extract 3 times with dichloromethane, combine the organic layers, wash the organic layer 3 times with 10% aqueous sodium bicarbonate solution and deionized water, and wash the organic layer with anhydrous After Na ₂ SO ₄ was dried, filtered, and the solvent was distilled off under reduced pressure to obtain a crude product, and then the crude product was purified by a chromatographic column to obtain the intermediate product MOBET;

(d) BDBIEA (812.46mg, 2mmol), MOBET (1.18gg, 6mmol), bis(dibenzylideneacetone)palladium (690.60mg, 1.2mmol), 1,1'-bis (Diphenylphosphino)ferrocene (98.70mg, 0.024mmol), anhydrous tripotassium phosphate (1.02g, 4.8mmol), 8mL toluene and 4mL acetone were added to a 50mL three-necked flask, and under nitrogen protection, the temperature Rise to 110°C and stir for 12h. After the reaction was completed, the reaction solution was cooled to room temperature, and the reaction solution was poured into 10 mL of saturated ammonium chloride aqueous solution, extracted 3 times with dichloromethane, and the organic phases were combined, and the organic layer was washed 3 times with saturated brine, and the organic layer was washed through After drying over anhydrous Na ₂ SO ₄ , filter, and distill off the solvent under reduced pressure to obtain the crude product, then purify the crude product with a chromatographic column to obtain the final product NABS-HD-1, which was identified by NMR spectroscopy.

The NMR data of the photoinitiator NABS-HD-1 are: ¹ H NMR (400MHz, Chloroform- d) δ8.63 (dd, J=7.6, 1.2Hz, 1H), 8.58 (dd, J=8.4, 1.2 Hz,1H),8.46(d,J=7.6Hz,1H),7.76(dd,J=8.8,7.6Hz,1H),7.60(d,J=7.6Hz,1H),7.33(d,J=8.8 Hz,2H), 6.88(d,J=8.8Hz,2H),4.45(t,J=6.4Hz,2H),4.33(s,2H),4.19(dd,J=4.8,4.4 Hz,2H), 3.85(t, J=6.0Hz, 2H), 3.80(s, 2H), 3.76(dd, J=4.8, 4.8Hz, 2H), 1.98(s, 3H).

The NMR data of the photoinitiator NABS-HD-1 are: ¹³ C NMR (100MHz, Chloroform- d) δ171.1, 164.1, 159.3, 144.9, 131.6, 130.9, 130.3, 130.1, 129.7, 127.1, 126.7, 124.1, 123.1 , 119.5, 114.3, 68.5, 67.9, 63.7, 55.3, 38.9, 37.1, 29.7, 20.9.

[Example 2]

The photoinitiator NABS-HD-2 has the following structural formula:

Its preparation method comprises the following steps:

(a) BHBD (5.83g, 16mmol), triethylamine (6.48g, 64mmol) and 150mL of anhydrous dichloromethane synthesized in Example 1 were added to a 250mL single-necked flask, and acryloyl chloride (4.35g, 48mmol) was dissolved in 20mL of anhydrous dichloromethane, added dropwise into a single-necked flask in an ice-water bath at 0°C, and stirred for 6h; after the reaction was completed, the solvent was distilled off under reduced pressure to obtain a crude product, which was then purified by a chromatographic column , to obtain an intermediate product named BDBIEB.

(b) BDBIEB (836.90mg, 2mmol), MOBET (1.18gg, 6mmol), bis(dibenzylideneacetone)palladium (690.60mg, 1.2mmol), 1,1'-bis (Diphenylphosphino)ferrocene (98.70mg, 0.024mmol), anhydrous tripotassium phosphate (1.02g, 4.8mmol), 8mL toluene and 4mL acetone were added to a 50mL three-necked flask, and under nitrogen protection, the temperature Rise to 110°C and stir for 12h. After the reaction was completed, the reaction solution was cooled to room temperature, and the reaction solution was poured into 10 mL of saturated ammonium chloride aqueous solution, extracted 3 times with dichloromethane, and the organic phases were combined, and the organic layer was washed 3 times with saturated brine, and the organic layer was washed through After drying over anhydrous Na ₂ SO ₄ , filter, and distill off the solvent under reduced pressure to obtain a crude product, then purify the crude product with a chromatographic column to obtain the final product NABS-HD-2, which was identified by NMR spectroscopy.

The NMR data of the photoinitiator NABS-HD-2 are: ¹ H NMR (400MHz, Chloroform- d) δ8.63 (dd, J=7.2, 1.2Hz, 1H), 8.59 (dd, J=7.2, 1.2 Hz,1H),8.46(d,J=8.0Hz,1H),7.76(dd,J=8.4,7.2Hz,1H),7.61(d,J=8.0Hz,1H),7.34(d,J=8.4 Hz,2H), 6.89(d,J=8.4Hz,2H),6.33(dd,J=17.2,1.6Hz,1H),6.05(d,J=17.6,10.4Hz,1H),5.73(d,J =10.4, 1.6Hz, 1H), 4.46(t, J=6.0Hz, 2H), 4.43(s, 2H), 4.29(dd, J=4.8, 4.8Hz, 2H), 3.87(t, J=6.0Hz , 2H), 3.81 (s, 2H), 3.80 (dd, J=4.8, 4.4Hz, 2H).

The NMR data of the photoinitiator NABS-HD-2 are: ¹³ C NMR (100MHz, Chloroform- d) δ166.1, 164.0, 163.9, 159.3, 144.9, 131.5, 130.8, 130.7, 130.2, 130.1, 129.5, 128.2, 128.1 , 126.9, 126.6, 123.8, 122.9, 119.3, 114.2, 68.5, 67.9, 63.7, 55.3, 38.9, 36.9.

[Example 3-8]

The purpose of embodiment 3-8 is to illustrate that the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives prepared in embodiment 1-2 can be effective in the environment where oxygen exists under the irradiation of UV-LED light source. Initiate the polymerization of monomer 1,6-hexanediol diacrylate (HDDA); the initiation activity is higher than that of existing photoinitiators 2959, 184, and 1173.

(1) prepare photosensitive resin composition: its proportioning is:

A: 1,6-hexanediol diacrylate (99.5 or 98 parts by mass)

B: Photoinitiator (0.5 parts by mass)

C: Photoinitiator (2.0 parts by mass)

Table 1 is the composition proportioning in each embodiment:

(2) Polymerization performance test

Test method: After stirring the above composition in the dark, apply it evenly on the potassium bromide salt sheet with a capillary tube to form a coating film of about 30 μm, and place it in a real-time infrared instrument (Thermo Fisher Scientific Corporation of the United States, model UVEC- 411, light intensity 100mW/cm ² ) to expose the coating film at a wavelength of 405nm, and the exposure time is 900s.

Test result: Accompanying drawing 3 shows, the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives prepared in embodiment 1-2 has good ultraviolet absorption ability under the emission wavelength of LED light source; Accompanying drawing 4 Show, the photosensitive resin composition that contains three kinds of commercial photoinitiators can not initiate monomer polymerization (embodiment 3-5) under the UV-LED light source irradiation of 405nm and the condition that oxygen exists, but contains the prepared by the present invention The photosensitive resin composition containing hydrogen donor thioether type naphthalimide derivative photoinitiator can successfully initiate photopolymerization (embodiment 6-8) under the conditions of 405nm UV-LED light source irradiation and the presence of oxygen, It shows that the hydrogen donor-containing sulfide-type naphthalimide derivative photoinitiator prepared in the present invention has good applicability in the UV-LED aerobic photocuring system.

[Example 9]

The purpose of this example is to illustrate that the photoinitiator NABS-HD-2 containing a hydrogen donor sulfide-type naphthalimide derivative prepared in Example 2 can have a lower mobility in the polymer film.

Test method: Weigh 0.01 g of the hydrogen donor-containing sulfide-type naphthalimide derivative photoinitiator prepared in Example 1-2 and 2.00 g of 1,6-hexanediol diacrylate (HDDA) respectively. g mixed to make a photosensitive solution; use a 1-2mm thick silicone film to make a template, and place a 2mm thick glass sheet on the bottom of the template; insert the photosensitive solution into the template, spread evenly without leaving air bubbles, and cover with a cover glass; Irradiate the photosensitive liquid with a 405nm LED light source until the photosensitive liquid is solidified; grind the cured resin to powder, take 1g of the ground resin powder, and soak it in 20mL of anhydrous acetone for 3 days; filter the sample to remove the solid to obtain the liquid, and use the US The liquid chromatogram obtained by Waters company's liquid mass spectrometry instrument, accompanying drawing 5.

Test result: Accompanying drawing 5 shows, for the liquid phase chromatogram after the polymer membrane extraction that comprises NABS-HD-1, the peak a that appears at 5.71min place belongs to HDDA molecule, the peak b that appears at 6.40min place belongs to polymer The NABS-HD-1 molecule contained in , and the peak is very obvious, which indicates that there are NABS-HD-1 molecules free in the polymer, and it is easy to migrate out of the polymer. As for the liquid chromatogram of NABS-HD-2 polymer film after extraction, only the peak of HDDA appears in the figure, and no chromatographic peak of NABS-HD-2 is found. This shows that the probability of NABS-HD-2 migrating out of the polymer matrix is much lower than that of NABS-HD-1. anchored to the polymer backbone, making migration difficult. Photoinitiator NABS-HD-2 has excellent migration stability.

The above are only preferred implementations of the present invention, and the scope of protection of the present invention is not limited to the above examples, and various technical solutions that have no substantial difference from the concept of the present invention are within the scope of protection of the present invention.

Claims (10)

1. A hydrogen-donating body thioether type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring, characterized in that, the hydrogen-donating body thioether type naphthalimide derivatized The structural formula of the species photoinitiator is as follows:

Wherein the value of n is 1; R ₁ is vinyl, methyl; R ₂ is methoxy. 2. a kind of preparation method that is applicable to UV-LED aerobic light curing described in claim 1 contains hydrogen donor sulfide type naphthalimide derivative photoinitiator, it is characterized in that, its synthetic technique is as follows Shown: (a)

(b)

(c)

(d)

3. according to claim 2, be applicable to the preparation method of the hydrogen donor sulfide type naphthalimide derivative photoinitiator that is applicable to UV-LED aerobic photocuring, it is characterized in that: described photoinitiator The preparation method comprises the following steps: (1) In step a, the primary amine and 4-bromo-1,8-naphthalene dicarboxylic anhydride are added to the reaction vessel and reacted for 24 hours at 60-100°C; Washed with water and ethanol several times to obtain brownish red solid intermediate product A; (2) In step b, the intermediate product A, acid chloride and organic base are added to the reaction vessel, anhydrous organic solvent is added, and reacted at 0-5°C for 6 hours; after the reaction, the anhydrous organic solvent is distilled off under reduced pressure to obtain Crude product, then purify the crude product with a chromatographic column to obtain a pale yellow solid intermediate B; (3) In step c, the

Add acetic anhydride and catalyst to the reactor, heat and reflux for 12 hours and stir; after the reaction, cool and extract with dichloromethane, combine the organic layers, wash the organic layers with a certain concentration of carbonate aqueous solution, and then wash with deionized water , the organic layer was dried by a desiccant, filtered, and the solvent was distilled off under reduced pressure to obtain a crude product, and then the crude product was purified with a chromatographic column to obtain a colorless liquid intermediate product C; (4) In step d, mix intermediate product B prepared in step b, intermediate product C prepared in step c, palladium catalyst, iron complex and inorganic base, and add an appropriate amount of organic solvent 1 and organic solvent 2, React in a nitrogen atmosphere and at 80-120°C for 24 hours; after the reaction, cool down, pour the reaction solution into an appropriate amount of saturated salt solution to wash, then extract with dichloromethane, combine the organic phases, wash the organic layer with saturated brine, and organic After the layer is dried with a desiccant, filter, remove the solvent by distillation under reduced pressure to obtain a crude product, then purify the crude product with a chromatographic column to obtain the final product; the organic solvent 1 is the same or different from the organic solvent 2, and is independently selected from toluene, One or more of dichloromethane, methanol, acetone, petroleum ether, ethyl acetate, and ethanol. 4. the preparation method of the hydrogen donor sulfide type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring according to claim 3, characterized in that, in the step a, The molar number of the primary amine is 1-10 times that of 4-bromo-1,8-naphthalene dicarboxylic anhydride; the reaction temperature is 70-90°C. 5. the preparation method of the hydrogen donor sulfide type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring according to claim 3, characterized in that: in the step b, The acid chloride is selected from acetyl chloride or acryloyl chloride; the number of moles of the acid chloride is 1 to 6 times that of the intermediate product A; the organic base is selected from triethylamine, diethylamine, 4-dimethylaminopyridine, pyridine, One or more of 3-picoline and 2-picoline; the number of moles of the organic base is 1 to 7 times that of the intermediate product A; the anhydrous organic solvent is selected from anhydrous dichloromethane, One or more of absolute ethanol, anhydrous petroleum ether, anhydrous acetone, anhydrous toluene, and anhydrous tetrahydrofuran; the reaction temperature is 0-2°C. 6. the method for preparing the photoinitiator containing hydrogen donor sulfide type naphthalimide derivatives suitable for UV-LED aerobic photocuring according to claim 3, characterized in that: in the step c, The molar number of the acetic anhydride is

0.5 to 4.5 times; the catalyst is one or more of ferric chloride, ferrous chloride, cupric chloride, cuprous chloride, nickel chloride, aluminum chloride, sodium nitrate, potassium nitrate, magnesium nitrate species; the number of moles of the catalyst is

0.001～0.020 times; the carbonate aqueous solution is one or more of sodium carbonate aqueous solution, potassium carbonate aqueous solution, ammonium carbonate aqueous solution, sodium bicarbonate aqueous solution, potassium bicarbonate aqueous solution, ammonium bicarbonate aqueous solution; the carbon The concentration of the aqueous salt solution is 1% to 25%. 7. The preparation method of the hydrogen-donor sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring according to claim 3, characterized in that: in the step d, The palladium catalyst is selected from bis(dibenzylideneacetone)palladium, tris(dibenzylideneacetone)dipalladium, bis(triphenylphosphino)palladium acetate, bis(di-tert-butylphenylphosphine)dichloro One or more of palladium chloride, bis(3,5,3',5'-dimethoxydibenzylideneacetone) palladium; the iron complex is selected from 1,1'-bis(diphenyl phosphino)ferrocene, 1,1-bisdiphenylphosphinoferrocene nickel chloride, (S,S)-(-)-2,2'-bis[-(N,N-dimethylamine base) (phenyl) methyl]-1,1'-bis(diphenylphosphino)ferrocene; the inorganic base is selected from sodium hydroxide, calcium hydroxide, aluminum hydroxide , lithium hydroxide, magnesium hydroxide, zinc hydroxide, anhydrous tripotassium phosphate or one or more; the number of moles of the palladium catalyst is 0.1 to 0.8 times that of the intermediate product B; the moles of the iron complex The number of moles of the intermediate product C is 0.10 to 0.20 times that of the intermediate product B; the molar number of the inorganic base is 1.0 to 5.0 times that of the intermediate product B; the molar number of the intermediate product C is 1 to 5 times that of the intermediate product B; the reaction temperature 90-115°C; the volume of the organic solvent 1 is 1-6 times that of the organic solvent 2; the total volume of the organic solvent 1 and the organic solvent 2 is 1-24 mL; the saturated salt solution is selected from saturated chlorinated One or more of ammonium solution, saturated ammonium sulfate solution, saturated magnesium chloride solution, saturated sodium sulfate solution, saturated potassium chloride solution, and saturated potassium nitrate solution. 8. The preparation method of the hydrogen donor sulfide-type naphthalimide derivative photoinitiator suitable for UV-LED aerobic photocuring according to claim 3, characterized in that: in the step c, The desiccant is selected from one or more of anhydrous magnesium sulfate, anhydrous sodium sulfate, anhydrous magnesium chloride, and anhydrous calcium chloride. 9. A free radical photocurable composition, characterized in that, comprising the hydrogen donor sulfide type naphthalimide derivative class photoinitiator suitable for UV-LED aerobic photocuring described in claim 1 agent; the composition comprises 0.1%-5% of the described hydrogen-donor-containing sulfide-type naphthalimide derivative photoinitiator and 95%-99.9% of photocurable resin or monomer, based on the composition gross weight. 10. The composition according to claim 9, wherein the photocurable resin is selected from the group consisting of epoxy (meth)acrylic resin, polyurethane (meth)acrylic resin, polyester (meth)acrylic resin, polyester One or more of ether (meth)acrylic resins, acrylated poly(meth)acrylic resins; the monomer is one or more of monofunctional or polyfunctional (meth)acrylates Various.

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