Aliphatic cyclic polyether imide high-performance photocuring material and preparation method thereof

Abstract

The application belongs to the technical field of high polymer materials, and particularly relates to a kind of alicyclic polyetherimide high-performance light-cured material and a preparation method thereof. An alicyclic methacrylate acrylate monomer is synthesized by ring-opening reaction of an alicyclic epoxy monomer and a carboxyl group, and an alicyclic imide monomer is prepared by Michael addition reaction of the alicyclic methacrylate acrylate. An alicyclic epoxy imide monomer is generated by epoxidation reaction of the alicyclic imide monomer and an oxidizing agent. The alicyclic epoxy imide monomer is subjected to ring-opening polymerization to obtain an alicyclic polyetherimide material. The material can be prepared into an alicyclic polyetherimide high-performance light-cured film by ultraviolet light curing. The main chain and the side chain of the alicyclic polyetherimide high-performance light-cured material are both alicyclic polyether rigid structures, and the material contains acrylate groups, has good toughness, heat resistance, weather resistance, and electrical properties, and can be used in the fields of IC carrier board solder resist ink, electronic packaging, flexible display substrate, photoresist and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of high polymer materials, and particularly relates to a kind of alicyclic polyether imide high-performance light-cured material and a preparation method thereof. BACKGROUND

[0002] UV curing has a wide range of applications in coatings and inks, adhesives, electronics industry, and biomedical science. Light-cured materials have fast curing speed, high production efficiency, no or less organic solvents, reduced environmental pollution, and can be adjusted according to the requirements to obtain materials with different properties.

[0003] At present, in the manufacturing and packaging processes of numerous electronic devices, high-performance sealant, special ink and other polymer materials are involved, including circuit ink and PCB photosensitive developing solder resist ink required for printed electronic circuit board manufacturing. With the increasing precision of electronic device manufacturing, the performance requirements of packaging materials and PCB ink are also increasingly stringent. Traditional aromatic packaging materials and solder resist materials cannot meet the performance requirements. The biggest defect is that the traditional packaging materials are difficult to improve in water and oxygen barrier property, thermal expansion coefficient, yellowing resistance and other key properties. For the photosensitive developing solder resist ink used for IC carrier board (new generation chip packaging technology), it is difficult for traditional aromatic epoxy-based materials to obtain sufficient developing resolution, low CTE, high T g , high hardness and other properties. In view of the current situation, it is necessary to develop a kind of alicyclic polyether imide high-performance light-cured material to improve the comprehensive performance of light-cured film and meet the requirements of more complex applications in the future. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the application provides a preparation method of alicyclic polyether imide high-performance light-cured material with a new structure. The application introduces alicyclic structure into the polymer molecular chain, generates multifunctional alicyclic polyether imide light-cured resin through Michael addition reaction, epoxidation reaction and ring-opening polymerization reaction. The resin contains acrylate groups and can be cured into a film in tens of seconds under UV light. The main chain and side chain of the resin both contain alicyclic structure, which improves the transparency and rigidity of the cured film and improves the optical properties and mechanical properties of the cured resin.

[0005] The object of the application can be achieved by the following technical solutions:

[0006] In a first aspect, the application provides a preparation method of alicyclic polyether imide high-performance light-cured material, comprising the following steps:

[0007] S1, reacting the epoxy group of an alicyclic epoxy monomer with the carboxyl group of acrylic acid or acrylic acid derivative in the presence of a polymerization inhibitor and a catalyst to synthesize an alicyclic methacrylate acrylate monomer;

[0008] S2, dissolve the alicyclic methacrylate acrylate monomer synthesized in step S1 and the imide ring monomer containing a cyclic double bond at the end group in a solvent, and add a catalyst to perform a Michael addition reaction between the N-H structure of the imide ring monomer and the acrylate double bond structure to synthesize an alicyclic imide monomer;

[0009] S3, dissolve the alicyclic imide monomer synthesized in step S2, an oxidizing agent, and sodium bicarbonate in a solvent, and after reaction, obtain an alicyclic epoxy imide monomer through washing and purification;

[0010] S4, dissolve the alicyclic epoxy imide monomer synthesized in step S3 in a solvent, add an initiator and a catalyst, and perform ring-opening polymerization reaction, and after reaction, obtain an alicyclic polyether imide monomer through washing and purification;

[0011] S5, mix the alicyclic polyether imide monomer obtained in step S4 and a photoinitiator, and after ultraviolet light curing, obtain an alicyclic polyether imide high-performance light-cured film.

[0012] The application first synthesizes an alicyclic methacrylate acrylate monomer by reacting the epoxy group of an alicyclic epoxy monomer with the carboxyl group of an acrylic acid or an acrylic acid derivative, which introduces acrylate groups and methacrylate groups, the former being used for Michael addition reaction and the latter being used for photopolymerization reaction; then the synthesized alicyclic methacrylate acrylate monomer and an imide ring monomer containing a cyclic double bond at the end group are subjected to Michael addition reaction between the N-H structure of the imide monomer and the acrylate double bond structure to synthesize an alicyclic imide monomer, which avoids the cumbersome steps of thermal imidization and the long reaction time, greatly improving the reaction efficiency; then the end group double bond is epoxidized by an oxidizing agent to obtain an alicyclic epoxy imide monomer; the alicyclic epoxy imide monomer is subjected to ring-opening polymerization reaction to obtain an alicyclic polyether imide monomer, and the polyether backbone can improve the comprehensive performance of the material; finally, the alicyclic polyether imide monomer is mixed with a photoinitiator, and after ultraviolet light curing, a light-cured film is prepared, which adopts the method of free radical photopolymerization and is efficient and more suitable for industrial production. The alicyclic polyether imide high-performance light-cured material prepared by the application has excellent toughness, heat resistance, weather resistance, and electrical properties, and has wide application prospects in the fields of IC carrier board solder mask ink, electronic packaging, flexible display substrate, photoresist, etc.

[0013] Preferably, in step S1, the alicyclic epoxy monomer includes but is not limited to 3,4-epoxy cyclohexyl methacrylate and 4-vinyl epoxy cyclohexane; the acrylic acid derivative includes but is not limited to methacrylic acid and beta-acryloyloxy propionic acid; the alicyclic methacrylate acrylate monomer has both acrylate groups and methacrylate groups, the former being used for Michael addition reaction and the latter being used for photopolymerization reaction.

[0014] Preferably, in step S1, the reaction temperature between the carboxyl group and the epoxy group is 105°C, and the reaction time is 10–12 h. Preferably, in step S1, the polymerization inhibitors used in the reaction include, but are not limited to, butylated hydroxytoluene (BHT) and p-hydroxyanisole (MEHQ).

[0015] Preferably, in step S1, the catalyst includes, but is not limited to, chromium isooctanoate.

[0016] Preferably, in step S1, the molar ratio of the alicyclic epoxy monomer to acrylic acid or the alicyclic epoxy monomer to methacrylic acid is 1.1:1.

[0017] Preferably, in step S2, the imide ring monomer containing a cyclic double bond at the end group includes, but is not limited to, 1,2,3,6-tetrahydrophthalimide and 5-norbornene-2,3-dicarboximide.

[0018] Preferably, in step S2, the solvent includes, but is not limited to, dichloromethane and ethyl acetate.

[0019] Preferably, in step S2, the catalyst includes, but is not limited to, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

[0020] Preferably, in step S2, the Michael addition reaction is carried out at a temperature of 70°C to 80°C for 8 to 10 hours.

[0021] Preferably, in step S2, the molar ratio of the alicyclic methacrylate acrylate monomer to the imide cyclic monomer with a cyclic double bond at the end group is 1.1:1.

[0022] Preferably, in step S2, the product obtained after the reaction is acid-washed and washed with saturated NaCl water to obtain a viscous and transparent alicyclic imide monomer.

[0023] Preferably, in step S3, the oxidant includes, but is not limited to, m-chloroperoxybenzoic acid and hydrogen peroxide.

[0024] Preferably, in step S3, the solvent includes, but is not limited to, dichloromethane and dichloroethane.

[0025] Preferably, in step S3, the molar ratio of the oxidant to the alicyclic imide monomer is 3-3.5:1, and the molar ratio of sodium bicarbonate to the oxidant is 1:1.

[0026] More preferably, in step S3, the reaction temperature is room temperature and the reaction time is 20-24 hours.

[0027] Preferably, in step S3, the product obtained after the reaction is washed with alkali and NaCl water to obtain a viscous and transparent alicyclic epoxyimide monomer.

[0028] Preferably, in step S4, the solvent includes, but is not limited to, ethyl acetate and dichloromethane.

[0029] Preferably, in step S4, the initiator includes, but is not limited to, trimethylolpropane (TMP), methanol, and glycerol.

[0030] Preferably, in step S4, the catalyst is boron trifluoride diethyl ether.

[0031] Preferably, in step S4, the reaction temperature of the ring-opening polymerization reaction is 45–60°C, and the reaction time is 4–6 h.

[0032] More preferably, in step S4, the molar ratio of the initiator to the alicyclic epoxy imide monomer is 1:5, and the molar ratio of the catalyst to the alicyclic epoxy imide monomer is 1:25.

[0033] Preferably, in step S4, the product obtained after the reaction is washed with water to obtain a viscous and transparent alicyclic polyether imide monomer.

[0034] Preferably, in step S5, the photoinitiator includes, but is not limited to, α,α-dimethoxy-α-phenylacetophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone (D1173), 1-hydroxy-cyclohexylphenyl ketone, 2-methyl-1-[4-methylmercaptophenyl]-2-morpholinopropanone-1,2-phenyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) or phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide (BAPO).

[0035] Preferably, in step S5, the amount of photoinitiator is 0.5 to 2% of the weight percentage of the alicyclic polyether imide monomer.

[0036] Preferably, in step S5, the ultraviolet light intensity is 30–40 mW / cm². 2 The illumination time is 60-80 seconds.

[0037] Preferably, in step S5, after ultraviolet irradiation, the product is placed in an oven at 80°C and dried for 6–10 hours.

[0038] Secondly, the present invention provides a high-performance photocurable alicyclic polyether imide material prepared by the above preparation method, wherein the structure of the high-performance photocurable alicyclic polyether imide material is shown below:

[0039]

[0040] In the formula, n is any integer from 2 to 5; the group R is the acrylate double bond in the alicyclic methacrylate acrylate monomer. After the transformation, the other structures of the alicyclic methacrylate acrylate monomer remain unchanged. The alicyclic methacrylate acrylate monomer contains both methacrylate and acrylate groups, wherein the methacrylate group structure is shown in Figure I, and the acrylate group structure is shown in Figure II.

[0041]

[0042] Thirdly, the present invention provides the application of the above-mentioned alicyclic polyether imide high-performance photocurable material in the field of optoelectronic devices.

[0043] The alicyclic polyetherimide high-performance photocurable film prepared by the method of this invention has better toughness, heat resistance, weather resistance and electrical properties, providing a new method for the application development of IC substrate solder resist ink, electronic packaging, flexible display substrate, photoresist and other fields.

[0044] The beneficial effects that this application can produce are as follows:

[0045] This invention discloses a method for preparing a high-performance photocurable alicyclic polyether imide material. First, an alicyclic methacrylate acrylate monomer is synthesized through a ring-opening reaction of an alicyclic epoxy monomer with a carboxyl group. Then, an alicyclic imide monomer is prepared from the alicyclic methacrylate acrylate monomer via a Michael addition reaction. The alicyclic imide monomer is then subjected to an epoxidation reaction with an oxidant to generate an alicyclic epoxy imide monomer. Finally, the alicyclic epoxy imide monomer undergoes ring-opening polymerization to obtain the alicyclic polyether imide material. This material can be UV-cured to prepare high-performance photocurable polyether imide films. The high-performance photocurable alicyclic polyether imide material prepared by this method not only has a rigid alicyclic polyether main chain but also contains alicyclic rigid structures in its side chains, along with acrylate groups, endowing the material with excellent toughness, heat resistance, weather resistance, and electrical properties. It can be used in IC substrate solder resist inks, electronic packaging, flexible display substrates, photoresists, and other fields. Attached Figure Description

[0046] Figure 1 This is a reaction route diagram for preparing the high-performance photocurable film of alicyclic polyether imide in Example 1.

[0047] Figure 2 The images show actual photos of the alicyclic polyetherimide high-performance photocurable films prepared in Examples 1, 2, and 1.

[0048] Figure 3Thermogravimetric analysis (TGA) diagrams of the alicyclic polyetherimide high-performance photocurable films prepared in Examples 1, 2, and 1.

[0049] Figure 4 The images show the DSC diagrams of the high-performance photocurable films of alicyclic polyetherimide prepared in Examples 1, 2 and Comparative Example 1. Detailed Implementation

[0050] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0051] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the experimental materials used in the following embodiments are all available through conventional commercial channels.

[0052] Example 1

[0053] A method for preparing high-performance photocurable alicyclic polyetherimide materials, the specific preparation method including the following steps:

[0054] (1) Preparation of alicyclic methacrylate acrylate monomers

[0055] The synthesis reaction formula is as follows:

[0056]

[0057] The specific preparation method is as follows:

[0058] 0.72 g (0.01 mol) of acrylic acid (AA), 0.0018 g (0.25 wt% relative to AA) of butylated hydroxytoluene (BHT) and 0.0018 g (0.25 wt% relative to AA) of p-hydroxyanisole (MEHQ) were added to a three-necked flask equipped with a reflux condenser, thermometer, mechanical stirrer and continuous nitrogen purging. The temperature was slowly raised to 105 °C, and 0.00648 g (0.9 wt% relative to AA) of chromium isooctanoate was added. Then, 2.16 g (0.011 mol) of 3,4-epoxycyclohexylmethyl methacrylate was added at 105 °C over a period of about 6 hours. After the reaction was completed at a constant temperature of 105 °C ± 2 °C, a transparent product was obtained, which was named CHOMA-AA.

[0059] The CHOMA-AA prepared in this step was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum in DMSO-d6 solvent were 6.33–5.91 ppm (3H, -CH=CH2), 6.03 ppm and 5.65 ppm (2H, -C=CH2), 5.03–4.77 ppm (1H, alicyclic O=CO-CH-), 3.95 ppm (2H, -CH2-OC=O), 3.75 and 3.65 ppm (1H, alicyclic -CH-O-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic -CH-, alicyclic -CH2-). The peak positions in the IR absorption spectrum were 3400 cm⁻¹. -1 (OH stretching vibration), 2935cm -1 and 2863cm -1 (Alicyclic CH stretching vibration), 1714 cm -1 (C=O stretching vibration), 1666cm -1 (C=C stretching vibration); the relative molecular mass of CHOMA-AA is 268.13.

[0060] (2) Preparation of alicyclic imide monomers

[0061] The synthesis reaction formula is as follows:

[0062]

[0063] The specific preparation method is as follows:

[0064] The product CHOMA-AA (2.95 g, 0.011 mol), 1,2,3,6-tetrahydrophthalimide (1.51 g, 0.01 mol), and catalyst DBU (1 mL) obtained in step (1) were sequentially added to a flask and stirred in an oil bath at 75 °C for 8 h. The resulting product was dissolved in dichloromethane and washed three times with a 1 mol / L dilute hydrochloric acid solution and once with a saturated sodium chloride solution. The dichloromethane was then removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure, pale yellow, viscous product, which is the alicyclic imide monomer PIM-2.

[0065] The product PIM-2 was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum in DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 5.83 ppm (2H, cyclic -C=C-), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.10 ppm (2H, -CH-CO-), 2.52 ppm (2H, -CH2-CO-), 2.28 ppm (4H, -CH2-C=C-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic -CH-, alicyclic -CH2-). The peak position in the IR absorption spectrum was 3488 cm⁻¹. -1 (OH stretching vibration), 696cm -1 (Out-of-plane bending vibration of ring C), 813cm -1 and 1635cm -1 (C=C stretching vibration), original 3212cm -1 The characteristic absorption peak of -NH- disappeared; the relative molecular mass of PIM-2 is 419.19.

[0066] (3) Preparation of alicyclic epoxyimide monomers

[0067] The synthesis reaction formula is as follows:

[0068]

[0069] The specific preparation method is as follows:

[0070] The product PIM-2 (4.19 g, 0.01 mol) from step (2) was dissolved in 50 mL of dichloroethane, and then m-chloroperoxybenzoic acid (2.59 g, 0.015 mol) and sodium bicarbonate (1.26 g, 0.015 mol) were added. The mixture was stirred at room temperature for 24 h. The resulting solution was washed three times with saturated sodium bicarbonate aqueous solution and once with saturated sodium chloride aqueous solution. Then, dichloroethane was removed by rotary evaporation. The product was placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure, pale yellow, viscous product, which is the alicyclic epoxyimide monomer EPIM-2.

[0071] The product EPIM-2 was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum in DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.10 ppm (2H, -CH-CO-), 2.82 ppm (2H, epoxide-CH-), 2.52 ppm (2H, -CH2-CO-), 2.28 ppm (4H, -CH2-C=C-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic-CH-, alicyclic-CH2-). The peak position in the IR absorption spectrum was 813 cm⁻¹. -1 and 1635cm -1 (C=C stretching vibration), 796cm -1 (Characterial absorption peak of epoxy COC), originally 696 cm⁻¹ -1 The out-of-plane bending vibration peak of the terminal C=C double bond disappears; the relative molecular mass of EPIM-2 is 435.19.

[0072] (4) Preparation of alicyclic polyether imide monomers

[0073] The synthesis reaction formula is as follows:

[0074]

[0075] The specific preparation method is as follows:

[0076] 4.35 g (0.01 mol) of the product EPIM-2 from step (3), 50 ml of ethyl acetate, and 0.27 g (0.002 mol) of trimethylolpropane were added sequentially to a three-necked flask equipped with a reflux condenser, thermometer, mechanical stirrer, and continuous nitrogen purging. The temperature was raised to 55 °C, and then a mixed solution of 0.1 ml of boron trifluoride ether and 10 ml of ethyl acetate was added dropwise from a constant pressure funnel over 0.5 h. The reaction was continued for 6 h. After the reaction was completed, the resulting solution was washed three times with deionized water, and then the ethyl acetate was removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure viscous product, which is the alicyclic polyether imide monomer PEPIM-2.

[0077] The product PEPIM-2 was analyzed by 1H NMR and infrared absorption spectroscopy. The chemical shifts in the 400M NMR spectrum of DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.05-2.81 ppm (8H, -CH- and -CH2- on the polyether backbone), 2.52 ppm (2H, -CH2-CO-), 1.88 ppm (3H, -CH3), and 2.09-1.31 ppm (7H, alicyclic -CH- and alicyclic -CH2-). The peak position in the infrared absorption spectrum was 813 cm⁻¹. -1 and 1635cm -1 (C=C stretching vibration), the characteristic absorption peak of the original 796cm-1 epoxy COC disappeared.

[0078] (5) Preparation of photocurable films

[0079] The prepared PEPIM-2 (1g) was mixed with 1wt% free radical photoinitiator D1173 (0.01g), and ultrasonically dissolved at 55℃. The solution was then coated onto a tinplate sheet using a 700μm coating applicator. The sheet was then heated and leveled in a 60℃ oven for 2 hours, followed by exposure to light at an intensity of 38mW / cm². 2 High-performance photocurable films of alicyclic polyetherimide were obtained by exposing the films to UV light intensity for 60–90 s.

[0080] Infrared spectroscopy was performed on the high-performance UV-curable alicyclic polyetherimide film using an ATR module. Analysis of the infrared spectrum of the UV-cured film revealed that the prepolymer, after UV curing, exhibited a high density of 810 cm⁻¹. -1 The characteristic absorption peaks of the nearby acrylate double bonds have basically disappeared, and the prepolymer has changed from a resin state to a cured film state, indicating that the curing is complete.

[0081] Example 2

[0082] Preparation of high-performance photocurable materials of alicyclic polyether imide

[0083] The specific preparation method includes the following steps:

[0084] (1) Preparation of alicyclic methacrylate acrylate monomers

[0085] The synthesis reaction formula is as follows:

[0086]

[0087] The specific preparation method is as follows:

[0088] 0.86 g (0.01 mol) of methacrylic acid (MAA), 0.00215 g (0.25 wt% relative to MAA) of butylated hydroxytoluene (BHT) and 0.00215 g (0.25 wt% relative to MAA) of p-hydroxyanisole (MEHQ) were added to a three-necked flask equipped with a reflux condenser, thermometer, mechanical stirrer, and continuous nitrogen purging. The temperature was slowly raised to 105 °C, and 0.00774 g (0.9 wt% relative to MAA) of chromium isooctanoate was added. Then, 2.00 g (0.011 mol) of methyl acrylate (3,4-epoxycyclohexyl) was added at 105 °C over approximately 6 hours. After the reaction was completed at a constant temperature of 105 °C ± 2 °C, a transparent product was obtained, which was named CHOA-MAA.

[0089] The CHOA-MAA prepared in this step was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO-d6 solvent were 6.33–5.91 ppm (3H, -CH=CH2), 6.03 ppm and 5.65 ppm (2H, -C=CH2), 5.03–4.77 ppm (1H, alicyclic O=CO-CH-), 3.95 ppm (2H, -CH2-OC=O), 3.75 and 3.65 ppm (1H, alicyclic -CH-O-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic -CH-, alicyclic -CH2-). The characteristic peak of the IR absorption spectrum was at 3400 cm⁻¹. -1 (OH stretching vibration), 2935cm -1 and 2863cm -1 (Alicyclic CH stretching vibration), 1714 cm -1 (C=O stretching vibration), 1666cm -1 (C=C stretching vibration); the relative molecular mass of CHOA-MAA is 268.13.

[0090] (2) Preparation of alicyclic imide monomers

[0091] The synthesis reaction formula is as follows:

[0092]

[0093] The specific preparation method is as follows:

[0094] The product CHOA-MAA (2.95 g, 0.011 mol), 1,2,3,6-tetrahydrophthalimide (1.51 g, 0.01 mol), and catalyst DBU (1 mL) obtained in step (1) were sequentially added to a flask and stirred in an oil bath at 75 °C for 8 h. The resulting product was dissolved in dichloromethane and washed three times with a 1 mol / L dilute hydrochloric acid solution and once with a saturated sodium chloride solution. The dichloromethane was then removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure, pale yellow, viscous product, which is the alicyclic imide monomer PIM-3.

[0095] The product PIM-3 was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum in DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 5.83 ppm (2H, cyclic -C=C-), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.10 ppm (2H, -CH-CO-), 2.52 ppm (2H, -CH2-CO-), 2.28 ppm (4H, -CH2-C=C-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic -CH-, alicyclic -CH2-). The peak position in the IR absorption spectrum was 3488 cm⁻¹. -1 (OH stretching vibration), 696cm -1 (Out-of-plane bending vibration of ring C), 813cm -1 and 1635cm -1 (C=C stretching vibration), original 3212cm -1 The characteristic absorption peak of -NH- disappears. The relative molecular mass of PIM-3 is 419.19.

[0096] (3) Preparation of alicyclic epoxyimide monomers

[0097] The synthesis reaction formula is as follows:

[0098]

[0099] The specific preparation method is as follows:

[0100] The product PIM-3 (4.19 g, 0.01 mol) from step (2) was dissolved in 50 mL of dichloroethane, and then m-chloroperoxybenzoic acid (2.59 g, 0.015 mol) and sodium bicarbonate (1.26 g, 0.015 mol) were added. The mixture was stirred at room temperature for 24 h. The resulting solution was washed three times with saturated sodium bicarbonate aqueous solution and once with saturated sodium chloride aqueous solution. Then, dichloroethane was removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure, pale yellow, viscous product, which is the alicyclic epoxyimide monomer EPIM-3.

[0101] The product EPIM-3 was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum in DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.10 ppm (2H, -CH-CO-), 2.82 ppm (2H, epoxide-CH-), 2.52 ppm (2H, -CH2-CO-), 2.28 ppm (4H, -CH2-C=C-), 1.88 ppm (3H, -CH3), and 2.09–1.31 ppm (7H, alicyclic-CH-, alicyclic-CH2-). The peak position in the IR absorption spectrum was 813 cm⁻¹. -1 and 1635cm -1 The peaks at 796 cm⁻¹ (characteristic absorption peak of epoxy COC) and 796 cm⁻¹ (characteristic absorption peak of epoxy COC) are observed, while the out-of-plane bending vibration peak of the terminal C=C double bond at the original 696 cm⁻¹ has disappeared. The relative molecular mass of EPIM-3 is 435.19.

[0102] (4) Preparation of alicyclic polyether imide monomers

[0103] The synthesis reaction formula is as follows:

[0104]

[0105] The specific preparation method is as follows:

[0106] 4.35 g (0.01 mol) of the product EPIM-3 from step (3), 50 ml of ethyl acetate, and 0.27 g (0.002 mol) of trimethylolpropane were added sequentially to a three-necked flask equipped with a reflux condenser, thermometer, mechanical stirrer, and continuous nitrogen purging. The temperature was raised to 55 °C, and then a mixed solution of 0.1 ml of boron trifluoride ether and 10 ml of ethyl acetate was added dropwise from a constant pressure funnel over 0.5 h. The reaction was continued for 6 h. After the reaction was completed, the resulting solution was washed three times with deionized water, and then the ethyl acetate was removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure viscous product, which is the alicyclic polyether imide monomer PEPIM-3.

[0107] The product PEPIM-3 was analyzed by 1H NMR and infrared absorption spectroscopy. The chemical shifts in the 400M NMR spectrum of DMSO-d6 solvent were: 6.03 ppm and 5.65 ppm (2H, -C=CH2), 3.95 ppm (2H, -CH2-OC=O), 3.60 ppm (2H, -N-CH2), 3.05-2.81 ppm (8H, -CH- and -CH2- on the polyether backbone), 2.52 ppm (2H, -CH2-CO-), 1.88 ppm (3H, -CH3), and 2.09-1.31 ppm (7H, alicyclic -CH- and alicyclic -CH2-). In the infrared absorption spectrum: 813 cm⁻¹ -1 and 1635cm -1 (C=C stretching vibration), the characteristic absorption peak of the original 796cm-1 epoxy COC disappeared.

[0108] (5) Preparation of photocurable films

[0109] The prepared PEPIM-3 (1g) was mixed with 1wt% free radical photoinitiator D1173 (0.01g), and ultrasonically dissolved at 55°C until homogeneous. The solution was then coated onto a tinplate sheet using a 700μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38mW / cm². 2 High-performance photocurable films of alicyclic polyetherimide were obtained by exposing the films to UV light intensity for 60–90 s.

[0110] Infrared spectroscopy was performed on the high-performance UV-curable alicyclic polyetherimide film using an ATR module. Analysis of the infrared spectrum of the UV-cured film revealed that the prepolymer, after UV curing, exhibited a high density of 810 cm⁻¹. -1 The characteristic absorption peaks of the nearby acrylate double bonds have basically disappeared, and the prepolymer has changed from a resin state to a cured film state, indicating that the curing is complete.

[0111] Comparative Example 1

[0112] Preparation of high-performance photocurable materials of alicyclic polyether imide

[0113] (1) Preparation of alicyclic imide monomers

[0114] The synthesis reaction formula is as follows:

[0115]

[0116] The specific preparation method is as follows:

[0117] 1,2,3,6-Tetrahydrophthalimide (1.51 g, 0.01 mol), 3-(acryloyloxy)-2-hydroxypropyl methacrylate (2.36 g, 0.011 mol), and catalyst DBU (1 mL) were sequentially added to a flask, and then stirred in an oil bath at 75 °C for 8 h. The resulting product was dissolved in dichloromethane, washed three times with a 1 mol / L dilute hydrochloric acid solution, and once with a saturated sodium chloride solution. The dichloromethane was then removed by rotary evaporation. The product was then dried under vacuum at 40 °C for 8 h to obtain a relatively pure, pale yellow, viscous product, which is the alicyclic imide monomer PIM.

[0118] The product PIM was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO-d6 solvent were: 6.06 ppm and 5.67 ppm (2H, -C=CH2), 5.83 ppm (2H, ring -C=C-), 4.12–3.93 ppm (6H, -CH2-), 3.60 ppm (H, -CH-O-), 3.11 ppm (2H, -CH-C=O-), 2.52 ppm (2H, -CH2-C=O-), 2.36 and 2.20 ppm (4H, -CH2-C=C-), and 1.88 ppm (3H, -CH3). The peak position in the IR absorption spectrum was 3482 cm⁻¹. -1 (OH stretching vibration), 696cm -1 (Out-of-plane bending vibration of ring C = C-plane), 809cm -1 and 1633cm -1 (C=C stretching vibration), original 3212cm -1 The characteristic absorption peak of -NH- disappears; the relative molecular mass of PIM is 365.38.

[0119] (2) Preparation of alicyclic epoxyimide monomers

[0120] The synthesis reaction formula is as follows:

[0121]

[0122] The specific preparation method is as follows:

[0123] The product PIM (3.65 g, 0.01 mol) from step (1) was dissolved in 50 mL of dichloroethane, and then m-chloroperoxybenzoic acid (2.59 g, 0.015 mol) and sodium bicarbonate (1.26 g, 0.015 mol) were added. The mixture was stirred at room temperature for 24 h. The resulting solution was washed three times with saturated sodium bicarbonate aqueous solution and once with saturated sodium chloride aqueous solution. Then, dichloroethane was removed by rotary evaporation. The product was placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure pale yellow viscous product, which is the alicyclic epoxyimide monomer EPIM.

[0124] The product EPIM was analyzed by 1H NMR, IR absorption, and mass spectrometry. The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO-d6 solvent were: 6.06 ppm and 5.67 ppm (2H, -C=CH2), 4.12–3.93 ppm (6H, -CH2-), 3.60 ppm (H, -CH-O-), 3.11 ppm (2H, -CH-C=O-), 2.82 ppm (2H, epoxide -CH-), 2.52 ppm (2H, -CH2-C=O-), 2.36 and 2.20 ppm (4H, -CH2-C=C-), and 1.88 ppm (3H, -CH3). The peak position in the IR absorption spectrum was 813 cm⁻¹. -1 and 1635cm -1 (C=C stretching vibration), 797cm -1 (Characterial absorption peak of epoxy COC), originally 696 cm⁻¹ -1 The out-of-plane bending vibration peak of the terminal C=C double bond disappears; the relative molecular mass of EPIM is 381.38.

[0125] (3) Preparation of alicyclic polyether imide monomers

[0126] The synthesis reaction formula is as follows:

[0127]

[0128] The specific preparation method is as follows:

[0129] 3.81 g (0.01 mol) of the product EPIM from step (2), 50 ml of ethyl acetate, and 0.27 g (0.002 mol) of trimethylolpropane were added sequentially to a three-necked flask equipped with a reflux condenser, thermometer, mechanical stirrer, and continuous nitrogen purging. The temperature was raised to 55 °C, and then a mixed solution of 0.1 ml of boron trifluoride ether and 10 ml of ethyl acetate was added dropwise from a constant pressure funnel over 0.5 h. The reaction was continued for 6 h. After the reaction was completed, the resulting solution was washed three times with deionized water, and then the ethyl acetate was removed by rotary evaporation. The product was then placed in an oven and vacuum dried at 40 °C for 8 h to obtain a relatively pure viscous product, which is the alicyclic polyether imide monomer PEPIM.

[0130] The product PEPIM was analyzed by 1H NMR and infrared absorption spectroscopy. The chemical shifts in the 400M NMR spectrum of DMSO-d6 solvent were: 6.06 ppm and 5.67 ppm (2H, -C=CH2), 4.12–3.93 ppm (6H, -CH2-), 3.60 ppm (H, -CH-O-), 3.11 ppm (2H, -CH-C=O-), 3.05–2.81 ppm (8H, -CH- and -CH2- on the polyether backbone), 2.52 ppm (2H, -CH2-C=O-), 2.36 and 2.20 ppm (4H, -CH2-C=C-), and 1.88 ppm (3H, -CH3). In the infrared absorption spectrum: 813 cm⁻¹ -1 and 1635cm -1 (C=C stretching vibration), the characteristic absorption peak of the original 796cm-1 epoxy COC disappeared.

[0131] (4) Preparation of photocurable films

[0132] The prepared PEPIM (1g) was mixed with 1wt% free radical photoinitiator D1173 (0.01g), and ultrasonically dissolved at 55℃. The solution was then coated onto a tinplate sheet using a 700μm coating applicator. The sheet was then heated and leveled in a 60℃ oven for 2 hours, followed by exposure to light at an intensity of 38mW / cm². 2 High-performance photocurable films of alicyclic polyetherimide were obtained by exposing the films to UV light intensity for 60–90 s.

[0133] Infrared spectroscopy was performed on the high-performance UV-curable alicyclic polyetherimide film using an ATR module. Analysis of the infrared spectrum of the UV-cured film revealed that the prepolymer, after UV curing, exhibited a high density of 810 cm⁻¹. -1 The characteristic absorption peaks of the nearby acrylate double bonds have basically disappeared, and the prepolymer has changed from a resin state to a cured film state, indicating that the curing is complete.

[0134] Performance Analysis

[0135] (1) Appearance of the cured film

[0136] Figure 1 The images show physical photos of the alicyclic polyetherimide high-performance photocurable films prepared in Examples 1, 2, and Comparative Example 1. Numbers 1 to 3 in the images are PEPIM-2, PEPIM-3, and PEPIM, respectively. As can be seen from the images, the cured films are pale yellow, highly transparent, and have relatively high overall hardness.

[0137] (2) Pencil hardness and thermal stability analysis

[0138] The performance of the prepared photocurable film was tested using the following methods: (1) Pencil hardness was tested according to GB / T6739—2006; (2) TG test was performed using Netzsch's TG 209F1. Thermogravimetric analysis was used to test the thermal stability of the UV-cured film. The heating rate was 10℃ / min, and the temperature range was 25~700℃. (3) DSC test was performed using a Netzsch DSC-204F1 Phoenix differential scanning calorimeter to determine the glass transition temperature (T) of the UV-cured film. g The heating rate is 10℃ / min, and the temperature range is 25~250℃. Figure 2 , Figure 3 Thermogravimetric analysis (TGA) and DSC plots of the alicyclic polyetherimide high-performance photocurable films prepared in Examples 1, 2, and Comparative Example 1 are shown in Table 1 below. The data for 5% and 10% thermogravimetric analysis of the photocurable films under nitrogen and air, glass transition temperature, and pencil hardness are also shown in Table 1 below.

[0139] Table 1 Properties of Cured Films with Different Resins

[0140]

[0141] As shown in Table 1, the pencil hardness of these thermosetting films is greater than 3H, and PEPIM-2 and PEPIM-3 are harder than PEPIM. The temperatures of the cured films PEPIM-2 and PEPIM-3 in Examples 1 and 2 at 5% and 10% thermal weight loss are higher than those of the cured film PEPIM in Comparative Example 1. This may be because, in addition to the polyether main chain, PEPIM-2 and PEPIM-3 also have alicyclic structures introduced into their side chains, resulting in greater steric hindrance, increased rigidity, and better heat resistance. The glass transition temperatures of the cured films PEPIM-2 and PEPIM-3 in Examples 1 and 2 are higher than those of the comparative PEPIM. This may be because PEPIM does not have alicyclic structures introduced into its side chains and contains more alkane side groups, making its molecular chains more flexible. Therefore, the preparation method of the alicyclic polyether imide high-performance photocurable material proposed in this invention is feasible, and this implementation scheme has good industrialization prospects.

[0142] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A method for preparing a high-performance photocurable material of alicyclic polyether imide, characterized in that, Includes the following steps: S1. Alicyclic methacrylate acrylate monomers are synthesized through step one or step two: Step 1: The epoxy group of the alicyclic epoxy monomer 3,4-epoxycyclohexyl methacrylate is reacted with the carboxyl group of acrylic acid in the presence of a polymerization inhibitor and a catalyst to synthesize the alicyclic methacrylate acrylate monomer. Step 2: The epoxy group of the alicyclic epoxy monomer (3,4-epoxycyclohexyl) methyl acrylate is reacted with the carboxyl group of methacrylic acid in the presence of a polymerization inhibitor and a catalyst to synthesize the alicyclic methacrylate acrylate monomer. S2. The alicyclic methacrylate acrylate monomer synthesized in step S1 and the imide ring monomer containing a cyclic double bond at the end group are dissolved in a solvent, and a catalyst is added. The imide ring monomer undergoes a Michael addition reaction with the NH structure of the acrylate double bond to synthesize the alicyclic imide monomer. S3. The alicyclic imide monomer synthesized in step S2 is dissolved in a solvent with an oxidant and sodium bicarbonate. After the reaction, it is washed and purified to obtain the alicyclic epoxy imide monomer. S4. Dissolve the alicyclic epoxy imide monomer synthesized in step S3 in a solvent, add an initiator, add a catalyst dropwise, and carry out a ring-opening polymerization reaction. After the reaction, wash and purify to obtain the alicyclic polyether imide monomer. S5. After mixing the alicyclic polyether imide monomer and photoinitiator obtained in step S4, a high-performance photocurable film of alicyclic polyether imide is prepared by UV curing. In step S3, the oxidant is m-chloroperoxybenzoic acid; the reaction conditions are stirring at room temperature for 24 hours.

2. The method for preparing a high-performance photocurable alicyclic polyether imide material according to claim 1, characterized in that, In step S1, the reaction temperature of the carboxyl group and the epoxy group is 105°C, the reaction time is 12h, the polymerization inhibitor is at least one of butylated hydroxytoluene and p-hydroxyanisole, and the catalyst is chromium isooctanoate.

3. The method for preparing a high-performance photocurable alicyclic polyether imide material according to claim 1, characterized in that, In step S2, the imide ring monomer containing a cyclic double bond at the end group is at least one of 1,2,3,6-tetrahydrophthalimide and 5-norbornene-2,3-dicarboximide; the solvent is at least one of dichloromethane and ethyl acetate; and the catalyst is 1,8-diazabicyclo[5.4.0]undec-7-ene.

4. The preparation method of the alicyclic polyether imide high-performance photocurable material according to claim 1, characterized in that, In step S2, the Michael addition reaction is carried out at a temperature of 70°C to 80°C for 8 to 10 hours.

5. The method for preparing a high-performance photocurable alicyclic polyether imide material according to claim 1, characterized in that, In step S3, the solvent is at least one of dichloromethane and dichloroethane.

6. The method for preparing a high-performance photocurable alicyclic polyether imide material according to claim 1, characterized in that, In step S4, the solvent is at least one of ethyl acetate and dichloromethane; the initiator is at least one of trimethylolpropane, methanol, and glycerol; the catalyst is boron trifluoride diethyl ether; the reaction temperature of the ring-opening polymerization reaction is 45~60℃, and the reaction time is 4~6h.

7. The method for preparing a high-performance photocurable alicyclic polyether imide material according to claim 1, characterized in that, In step S5, the photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone or 1-hydroxycyclohexylphenyl ketone; the UV light intensity is 38 mw / cm². 2 The illumination time is 60-80 seconds.

8. A high-performance photocurable alicyclic polyether imide material prepared by any one of the preparation methods described in claims 1-7.

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