An epoxy resin for optical fiber array and a method for preparing the same

Abstract

The application discloses an epoxy resin for optical fiber arrays and a preparation method thereof, and belongs to the technical field of epoxy resin preparation. The epoxy resin for optical fiber arrays is composed of the following components in parts by weight: 50-80 parts of an epoxy resin, 5-30 parts of a modified functional resin, 5-10 parts of a toughening agent, 1-5 parts of an auxiliary agent, and 5-20 parts of a composite curing agent. The epoxy resin for optical fiber arrays prepared by the method has excellent thermal stability and mechanical strength, and also has low shrinkage and curing shrinkage stress, thereby avoiding the debonding between the optical fiber and the adhesive layer.

Description

Technical Field

[0001] This invention belongs to the field of epoxy resin preparation technology, specifically relating to an epoxy resin for fiber optic arrays and its preparation method. Background Technology

[0002] As optical fiber communication technology continues to evolve towards higher speeds, greater integration, and greater intelligence, the performance stability of fiber optic arrays, as the core component in optical modules for precise optical signal transmission and coupling, directly determines the reliability of the optical communication system. With the rapid development of 5G network construction, data center expansion, and autonomous driving, the application scenarios of fiber optic arrays are constantly expanding, placing more stringent demands on the comprehensive performance of packaging materials. Traditional adhesives are gradually revealing their limitations in the manufacturing process of fiber optic arrays: on the one hand, the small diameter of optical fibers and the need for nanometer-level alignment precision mean that ordinary adhesives have high curing shrinkage rates, easily leading to fiber misalignment and increased optical signal transmission loss; on the other hand, optical modules need to operate under complex environmental conditions for extended periods, and mismatches in the thermal expansion coefficients of materials may cause interface stress concentration, resulting in cracking of the packaging structure or performance degradation. Furthermore, as optical modules develop towards higher density and smaller volume, the packaging process of fiber optic arrays presents greater challenges to the flowability, wettability, and vibration resistance of adhesives. Epoxy resin, due to its unique molecular structure advantages, has become an ideal choice in the field of fiber optic array packaging.

[0003] Patent CN118931446A discloses a fluorescent epoxy resin adhesive and its preparation method. The epoxy resin adhesive is composed of adhesive A, adhesive B, and an oil-based fluorescent agent. The content of the oil-based fluorescent agent is 0.0001%-1%. This invention adds a small amount of fluorescent agent to the epoxy resin adhesive, allowing the product to be identified by the naked eye or a visual system under ultraviolet light to detect whether the epoxy resin adhesive has overflowed or sputtered, thereby screening out defective products. However, this epoxy resin adhesive still has significant shortcomings. The high curing shrinkage rate of the epoxy resin adhesive itself has not been effectively improved. During the curing process, the high shrinkage rate will lead to large internal stress, which may not only cause peeling and cracking between the adhesive layer and the adhered object, affecting the long-term stability and reliability of the bond, but also damage precision devices such as fiber optic arrays, causing fiber displacement, increasing optical signal transmission loss, and reducing product performance. Summary of the Invention

[0004] The purpose of this invention is to provide an epoxy resin for fiber optic arrays and its preparation method, which solves the technical problems of high curing shrinkage and poor mechanical properties of epoxy resins in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides an epoxy resin for fiber optic arrays, comprising the following components by weight: 50-80 parts epoxy resin, 5-30 parts modified functional resin, 5-10 parts toughening agent, 1-5 parts additives, and 5-20 parts composite curing agent.

[0007] Preferably, the method for preparing the modified functional resin includes the following steps:

[0008] Q1: 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, ditert-butyl dicarbonate and nano-iron oxide were added to anhydrous ethanol and stirred at room temperature. After the reaction was completed, the mixture was filtered, evaporated to dryness, dissolved, washed, separated, and evaporated to dryness to obtain compound a.

[0009] Q2: Sodium tripolyphosphate, p-chlorophenylglycine and acetone were added to a container in sequence. Cinnamyl chloride was added to the acetone and stirred until dissolved. The solution was then added dropwise to the container. After the addition was complete, the reaction continued. The mixture was filtered, washed, and dried to obtain compound b.

[0010] Q3: Compound a and triethylamine were added to dichloromethane, stirred, and placed in an ice bath to cool. A mixed solution of compound b and dichloromethane was added, and the mixture was stirred at room temperature. After the reaction was completed, saturated sodium bicarbonate solution was added, the mixture was washed, separated, and the organic phase was collected, dried, purified by vacuum distillation, and filtered to obtain compound c. Compound c was added to a container and heated in an oil bath to react. After the reaction was completed, the mixture was cooled, purified, and filtered to obtain the modified diamine.

[0011] Q4: Add the modified diamine and 4,4'-diaminodiphenyl ether to N-methylpyrrolidone, stir to dissolve, cool in an ice bath, then add hexafluorodianhydride, react in an ice bath, react at room temperature, then add a mixed solution of anhydrous acetic anhydride and anhydrous triethylamine, heat to react, then add to ethanol, wash, centrifuge, and vacuum dry to obtain the modified functional resin.

[0012] The synthesis reaction formula for the modified functional resin in the above process is as follows:

[0013]

[0014] The mass spectrometry analysis results for compound a were: m / z: 566.19 (100.0%), 567.19 (27.6%), 568.19 (5.1%); the mass spectrometry analysis results for compound b were: m / z: 315.07 (100.0%), 317.06 (32.0%), 316.07 (18.7%), 318.07 (6.1%), 317.07 (2.3%); and the mass spectrometry analysis result for compound c was: m / z: 1124.36 (100.0%). The percentages of the modified diamine were 1125.37 (64.9%), 1126.37 (23.2%), 1127.37 (6.1%), 1125.36 (1.5%), 1128.38 (1.2%), and 1126.36 (1.0%). The mass spectrometry analysis results of the modified diamine were: m / z: 924.26 (100.0%), 925.26 (54.8%), 926.27 (14.1%), 927.27 (3.3%), and 926.26 (2.4%).

[0015] Preferably, in Q1, the ratio of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, di-tert-butyl dicarbonate, nano-ferric oxide, and anhydrous ethanol is (6.32-7.01) g : (4.38-4.59) g : (0.21-0.35) g : (55-65) mL, the reaction is stirred for 10-12 h, filtered through a 0.45 μm organic filter membrane, dissolved in ethyl acetate, and washed with a saturated ammonium chloride solution.

[0016] Preferably, in Q2, the ratio of sodium tripolyphosphate, p-chlorophenylglycine, and cinnamoyl chloride is (8.52-9.16) g : (5.38-5.46) g : (7.81-8.17) g, and the reaction time is 4-6 h; in Q3, the molar ratio of compound a, triethylamine, and compound b is (1-1.3) : (2.2-2.6) : (2.2-2.8), the cooling time is 10-15 min, the stirring reaction time at room temperature is 30-45 min, and the oil bath heating reaction temperature is 200-220 °C.

[0017] Preferably, in Q4, the ratio of modified diamine, 4,4'-diaminodiphenyl ether, N-methylpyrrolidone, hexafluorodianhydride, anhydrous acetic anhydride, and anhydrous triethylamine is (0.073-0.082)g : (0.64-0.78)g : (6.5-8.5)mL : (1.91-2.17)g : (2.11-2.32)mL : (3.12-3.28)mL. The reaction is carried out in an ice bath for 10-20 min, the reaction time in the ice bath is 1-2 h, the reaction time at room temperature is 10-12 h, and the reaction temperature is raised to 90-100℃ for 10-12 h.

[0018] Preferably, the preparation method of the composite curing agent includes the following steps:

[0019] S1: 2,3,6,7-Tetramethylanthracene-9,10-dione was added to a container. Under nitrogen protection, cesium fluoride and tetrahydrofuran were added. After stirring at low temperature, trimethyl(trifluoromethyl)silane was added. After stirring, the mixture was heated to a higher temperature. After the reaction was completed, the mixture was filtered, washed, and purified to obtain product 1. Product 1 was added to tetrahydrofuran and heated under reflux until dissolved. Then concentrated hydrochloric acid was added, the mixture was stirred, cooled, filtered, and washed to obtain product 2.

[0020] S2: Under nitrogen protection, product 2 was added to a container containing anhydrous benzene, stirred, cooled, and trifluoromethanesulfonic acid was added. The reaction continued, distilled water was added, the product was extracted, evaporated to dryness, and purified to obtain product 3. Product 3 was added to a mixed solution of pyridine and distilled water, heated to reflux to dissolve, potassium permanganate was added, the reaction continued, ethanol was added, filtered, concentrated, and purified to obtain product 4.

[0021] S3: Add product 4 to acetic anhydride, heat to reflux until dissolved, stir to react, concentrate, purify to obtain product 5, mix product 5, epoxy acrylate and 2-hydroxy-2-methyl-1-phenylpropanone to obtain composite curing agent.

[0022] The synthesis reaction formula for product 5 in the above process is as follows:

[0023]

[0024] The mass spectrometry analysis results for product 1 were: m / z: 406.16 (100.0%), 407.16 (29.2%), 408.16 (4.3%), 408.15 (3.3%), 409.16 (1.0%); the mass spectrometry analysis results for product 2 were: m / z: 334.12 (100.0%), 335.12 (20.8%), 336.12 (2.4%); and the mass spectrometry analysis result for product 3 was: m / z: 394.15. (100.0%), 395.16 (27.3%), 396.16 (3.8%); Product 4, analyzed by mass spectrometry, has the following m / z values: 514.05 (100.0%), 515.05 (27.0%), 516.06 (5.5%); Product 5, analyzed by mass spectrometry, has the following m / z values: 478.03 (100.0%), 479.03 (27.3%), 480.04 (3.6%), 480.03 (1.4%).

[0025] Preferably, in S1, the ratio of 2,3,6,7-tetramethylanthracene-9,10-dione, cesium fluoride, tetrahydrofuran, and trimethyl(trifluoromethyl)silane is (10-12)g:(0.057-0.082)g:(500-600)mL:(6-9)mL, the low-temperature stirring temperature is -10 to -15℃, the stirring time is 10-15min, the stirring time is continued for 10-20min, the temperature is raised to 10-12℃, and the reaction is carried out for 3-5h; the ratio of product 1 to tetrahydrofuran is (10-12)g:(20-25)mL, and the stirring reaction time is 4-6h.

[0026] Preferably, in step S2, the ratio of product 2, anhydrous benzene, and trifluoromethanesulfonic acid is (5-7.5) g: (10-20) mL: (10-14) mL. After stirring for 10-15 min, the temperature is lowered to 0-1℃, and the reaction continues for 14-18 h. The ratio of product 3, pyridine, distilled water, and potassium permanganate is (5-7.5) g: (160-180) mL: (20-40) mL: (18-22) g, and the reaction continues for 14-18 h.

[0027] Preferably, in step S3, the ratio of product 4 to acetic anhydride is (5-7) g: (30-45) mL, and the stirring reaction time is 3-5 h; the ratio of product 5, epoxy acrylate, and 2-hydroxy-2-methyl-1-phenylpropanone is (3-8) g: (2-7) g: (0.03-0.05) g.

[0028] Preferably, the method for preparing an epoxy resin for fiber optic arrays includes the following steps:

[0029] Step 1: Under nitrogen protection, epoxy resin and modified functional resin are added to the reactor, heated and stirred to react, and a mixture is obtained.

[0030] Step 2: Add toughening agent and additives to the mixture, continue stirring, cool down, add composite curing agent, stir, vacuum degas, filter, and obtain epoxy resin for fiber array.

[0031] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0032] 1. In the process of preparing epoxy resin for fiber optic arrays, the present invention adds modified functional resin and composite curing agent, so that the prepared epoxy resin has excellent heat resistance and mechanical properties, as well as low shrinkage rate and curing shrinkage stress.

[0033] 2. The modified functional resin prepared in this invention is used as one of the raw materials for epoxy resin used in optical fiber arrays. It can effectively improve its heat resistance and mechanical properties, and also reduce shrinkage rate and curing shrinkage stress. The modified functional resin has excellent thermal stability. The introduced fluorine atoms can further reduce the polarity of the material, reduce energy loss during thermal motion, and improve its heat resistance. At the same time, the high-strength molecular chain structure contained in the modified functional resin forms an interpenetrating structure with the cross-linking network of epoxy resin, which synergistically improves tensile strength and modulus. Moreover, the low shrinkage characteristics of the modified functional resin can effectively balance the volume shrinkage of epoxy resin during curing, reduce curing shrinkage stress, and prevent the light-shielding optical fiber from debonding to the adhesive layer.

[0034] 3. The composite curing agent prepared in this invention is used as a curing component of epoxy resin for fiber optic arrays. This effectively improves the heat resistance and mechanical properties of the epoxy resin, and also reduces the shrinkage rate and internal stress. The composite curing agent undergoes a ring-opening addition reaction with the epoxy groups of the epoxy resin to form a three-dimensional network structure with high cross-linking density, which significantly improves thermal stability. The introduced fluorinated groups further reduce molecular polarity, reduce energy loss during thermal motion, and improve heat resistance. At the same time, the rigid network structure formed by the composite curing agent effectively enhances the stiffness and hardness of the epoxy resin. The acid anhydride contained therein has excellent compatibility with the epoxy resin, resulting in minimal volume shrinkage during the curing process and a significant reduction in curing shrinkage stress. This effectively prevents the fiber from debonding from the adhesive layer, improving the structural stability and signal transmission reliability of the fiber optic array. Detailed Implementation

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1: This example discloses a method for preparing a modified functional resin, including the following steps:

[0037] Q1: 6.68 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 4.48 g of di-tert-butyl dicarbonate and 0.28 g of nano-ferric oxide were added to 60 mL of anhydrous ethanol and stirred at room temperature for 12 h. After the reaction was completed, the mixture was filtered through a 0.45 μm organic filter membrane, evaporated to dryness, dissolved in ethyl acetate, washed with saturated ammonium chloride solution, separated, and evaporated to dryness to obtain compound a;

[0038] Q2: 8.84g sodium tripolyphosphate, 5.42g p-chlorophenylglycine and 10mL acetone were added to the container in sequence. 7.93g cinnamoyl chloride was added to 15mL acetone. After stirring and dissolving, the solution was added dropwise to the container. After the addition was complete, the reaction was continued for 6 hours. The mixture was then filtered, washed, and dried to obtain compound b.

[0039] Q3: 0.68 g of compound a and 0.25 g of triethylamine were added to 10 mL of dichloromethane. After stirring, the mixture was placed in an ice bath and cooled for 10 min. Then, a mixed solution of 1.91 g of compound b and 5 mL of dichloromethane was added. The mixture was stirred at room temperature for 45 min. After the reaction was completed, saturated sodium bicarbonate solution was added, and the mixture was washed, separated, and the organic phase was collected. The organic phase was dried, purified by vacuum distillation, and filtered to obtain compound c. Compound c was added to a container and heated in an oil bath at 200 °C. After the reaction was completed, the mixture was cooled, purified, and filtered to obtain the modified diamine.

[0040] Q4: Add 0.077g of modified diamine and 0.71g of 4,4'-diaminodiphenyl ether to 7.5g of N-methylpyrrolidone, stir to dissolve, cool in an ice bath for 20min, then add 2.04g of hexafluorodianhydride, react in an ice bath for 2h, then react at room temperature for 12h, then add a mixed solution of 2.21g of anhydrous acetic anhydride and 3.2mL of anhydrous triethylamine, heat to 90℃ and react for 12h, then add to ethanol, wash, centrifuge, and vacuum dry to obtain the modified functional resin.

[0041] This embodiment discloses a method for preparing a composite curing agent, including the following steps:

[0042] S1: 11 g of 2,3,6,7-tetramethylanthracene-9,10-dione was added to a container. Under nitrogen protection, 0.068 g of cesium fluoride and 550 mL of tetrahydrofuran were added. The mixture was stirred at -10 °C for 15 min, then 7.5 mL of trimethyl(trifluoromethyl)silane was added. The mixture was stirred for another 20 min, then heated to 10 °C and reacted for 5 h. After the reaction was completed, the mixture was filtered, washed, and purified to obtain product 1. 11 g of product 1 was added to 22.5 mL of tetrahydrofuran and heated under reflux until dissolved. Then, concentrated hydrochloric acid was added until no more white precipitate was added. The mixture was stirred for 4 h, cooled, filtered, and washed to obtain product 2.

[0043] S2: Under nitrogen protection, 6.25 g of product 2 was added to a container containing 15 mL of anhydrous benzene. After stirring for 15 min, the mixture was cooled to 0 °C, 12 mL of trifluoromethanesulfonic acid was added, and the reaction was continued for 14 h. Distilled water was added, the mixture was extracted, evaporated to dryness, and purified to obtain product 3. 6.25 g of product 3 was added to a mixed solution of 170 mL of pyridine and 30 mL of distilled water, heated to reflux to dissolve, and then 20 g of potassium permanganate was added. The reaction was continued for 18 h, followed by the addition of ethanol, filtration, concentration, and purification to obtain product 4.

[0044] S3: Add 6g of product 4 to 37.5mL of acetic anhydride, heat to reflux until dissolved, stir and react for 4h, concentrate and purify to obtain product 5. Mix 5.5g of product 5, 4.5g of epoxy acrylate and 0.04g of 2-hydroxy-2-methyl-1-phenylpropanone to obtain composite curing agent.

[0045] This embodiment discloses an epoxy resin for fiber optic arrays, which is composed of the following components by weight: 65 parts bisphenol F type epoxy resin, 17.5 parts modified functional resin, 7.5 parts dibutyl phthalate, 3 parts silane coupling agent KH-550, and 12.5 parts composite curing agent.

[0046] This embodiment discloses a method for preparing epoxy resin for fiber optic arrays, including the following steps:

[0047] Step 1: Under nitrogen protection, bisphenol F epoxy resin and modified functional resin are added to the reactor, heated and stirred to react, and a mixture is obtained.

[0048] Step 2: Add dibutyl phthalate and silane coupling agent KH-550 to the mixture, continue stirring, cool down, add composite curing agent, stir, vacuum degas, filter, and obtain epoxy resin for fiber array.

[0049] Example 2: This example discloses a method for preparing a modified functional resin, including the following steps:

[0050] Q1: 6.32 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 4.38 g of di-tert-butyl dicarbonate and 0.35 g of nano-ferric oxide were added to 65 mL of anhydrous ethanol and stirred at room temperature for 12 h. After the reaction was completed, the mixture was filtered through a 0.45 μm organic filter membrane, evaporated to dryness, dissolved in ethyl acetate, washed with saturated ammonium chloride solution, separated, and evaporated to dryness to obtain compound a;

[0051] Q2: 8.52g sodium tripolyphosphate, 5.38g p-chlorophenylglycine and 10mL acetone were added to the container in sequence. 7.81g cinnamoyl chloride was added to 15mL acetone. After stirring and dissolving, the solution was added dropwise to the container. After the addition was complete, the reaction was continued for 6 hours. The mixture was then filtered, washed, and dried to obtain compound b.

[0052] Q3: Add 0.56g of compound a and 0.22g of triethylamine to 10mL of dichloromethane, stir, place in an ice bath and cool for 10min. Add a mixed solution of 1.68g of compound b and 5mL of dichloromethane, stir at room temperature for 45min. After the reaction is complete, add saturated sodium bicarbonate solution, wash, separate and collect the organic phase, dry, distill under reduced pressure, purify, filter, and obtain compound c. Add compound c to a container and heat in an oil bath at 200℃. After the reaction is complete, cool, purify, filter, and obtain modified diamine.

[0053] Q4: Add 0.073g of modified diamine and 0.64g of 4,4'-diaminodiphenyl ether to 8.5g of N-methylpyrrolidone, stir to dissolve, cool in an ice bath for 20min, then add 1.91g of hexafluorodianhydride, react in an ice bath for 2h, then react at room temperature for 12h, then add a mixed solution of 2.11g of anhydrous acetic anhydride and 3.12mL of anhydrous triethylamine, heat to 90℃ and react for 12h, then add to ethanol, wash, centrifuge, and vacuum dry to obtain the modified functional resin.

[0054] This embodiment discloses a method for preparing a composite curing agent, including the following steps:

[0055] S1: 12g of 2,3,6,7-tetramethylanthracene-9,10-dione was added to a container. Under nitrogen protection, 0.057g of cesium fluoride and 600mL of tetrahydrofuran were added. The mixture was stirred at -10℃ for 15min, then 6mL of trimethyl(trifluoromethyl)silane was added. The mixture was stirred for another 20min, then heated to 10℃ and reacted for 5h. After the reaction was completed, the mixture was filtered, washed, and purified to obtain product 1. 10g of product 1 was added to 25mL of tetrahydrofuran and heated under reflux until dissolved. Concentrated hydrochloric acid was then added until no more white precipitate was added. The mixture was stirred for 4h, cooled, filtered, and washed to obtain product 2.

[0056] S2: Under nitrogen protection, 5g of product 2 was added to a container containing 20mL of anhydrous benzene. After stirring for 15min, the mixture was cooled to 0℃, 10mL of trifluoromethanesulfonic acid was added, and the reaction was continued for 14h. Distilled water was added, the mixture was extracted, evaporated to dryness, and purified to obtain product 3. 5g of product 3 was added to a mixed solution of 180mL of pyridine and 40mL of distilled water, heated to reflux to dissolve, and then 18g of potassium permanganate was added. The reaction was continued for 18h, followed by the addition of ethanol, filtration, concentration, and purification to obtain product 4.

[0057] S3: Add 5g of product 4 to 30mL of acetic anhydride, heat to reflux until dissolved, stir and react for 4h, concentrate and purify to obtain product 5. Mix 3g of product 5, 2g of epoxy acrylate and 0.05g of 2-hydroxy-2-methyl-1-phenylpropanone to obtain composite curing agent.

[0058] This embodiment discloses an epoxy resin for fiber optic arrays, which is composed of the following components by weight: 50 parts bisphenol F type epoxy resin, 30 parts modified functional resin, 10 parts dibutyl phthalate, 1 part silane coupling agent KH-550, and 20 parts composite curing agent.

[0059] This embodiment discloses a method for preparing epoxy resin for fiber optic arrays, including the following steps:

[0060] Step 1: Under nitrogen protection, bisphenol F epoxy resin and modified functional resin are added to the reactor, heated and stirred to react, and a mixture is obtained.

[0061] Step 2: Add dibutyl phthalate and silane coupling agent KH-550 to the mixture, continue stirring, cool down, add composite curing agent, stir, vacuum degas, filter, and obtain epoxy resin for fiber array.

[0062] Example 3: This example discloses a method for preparing a modified functional resin, including the following steps:

[0063] Q1: 7.01 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 4.59 g of di-tert-butyl dicarbonate and 0.21 g of nano-ferric oxide were added to 55 mL of anhydrous ethanol and stirred at room temperature for 12 h. After the reaction was completed, the mixture was filtered through a 0.45 μm organic filter membrane, evaporated to dryness, dissolved in ethyl acetate, washed with saturated ammonium chloride solution, separated, and evaporated to dryness to obtain compound a;

[0064] Q2: 9.16g sodium tripolyphosphate, 5.46g p-chlorophenylglycine and 10mL acetone were added to the container in sequence. 8.17g cinnamoyl chloride was added to 15mL acetone. After stirring and dissolving, the solution was added dropwise to the container. After the addition was complete, the reaction continued for 6 hours. The mixture was then filtered, washed, and dried to obtain compound b.

[0065] Q3: 0.73g of compound a and 0.28g of triethylamine were added to 10mL of dichloromethane. After stirring, the mixture was placed in an ice bath and cooled for 10min. Then, a mixed solution of 2.13g of compound b and 5mL of dichloromethane was added. The mixture was stirred at room temperature for 45min. After the reaction was completed, saturated sodium bicarbonate solution was added, the mixture was washed, separated, and the organic phase was collected. The organic phase was dried, purified by vacuum distillation, and filtered to obtain compound c. Compound c was added to a container and heated in an oil bath at 200℃. After the reaction was completed, the mixture was cooled, purified, and filtered to obtain the modified diamine.

[0066] Q4: Add 0.082g of modified diamine and 0.78g of 4,4'-diaminodiphenyl ether to 6.5g of N-methylpyrrolidone, stir to dissolve, cool in an ice bath for 20min, then add 2.17g of hexafluorodianhydride, react in an ice bath for 2h, then react at room temperature for 12h, then add a mixed solution of 2.32g of anhydrous acetic anhydride and 3.28mL of anhydrous triethylamine, heat to 90℃ and react for 12h, then add to ethanol, wash, centrifuge, and vacuum dry to obtain the modified functional resin.

[0067] This embodiment discloses a method for preparing a composite curing agent, including the following steps:

[0068] S1: 10g of 2,3,6,7-tetramethylanthracene-9,10-dione was added to a container. Under nitrogen protection, 0.082g of cesium fluoride and 500mL of tetrahydrofuran were added. The mixture was stirred at -10℃ for 15min, then 9mL of trimethyl(trifluoromethyl)silane was added. The mixture was stirred for another 20min, then heated to 10℃ and reacted for 5h. After the reaction was completed, the mixture was filtered, washed, and purified to obtain product 1. 12g of product 1 was added to 20mL of tetrahydrofuran and heated under reflux until dissolved. Concentrated hydrochloric acid was then added until no more white precipitate was added. The mixture was stirred for 4h, cooled, filtered, and washed to obtain product 2.

[0069] S2: Under nitrogen protection, 7.5 g of product 2 was added to a container containing 10 mL of anhydrous benzene. After stirring for 15 min, the mixture was cooled to 0 °C, 14 mL of trifluoromethanesulfonic acid was added, and the reaction was continued for 14 h. Distilled water was added, the mixture was extracted, evaporated to dryness, and purified to obtain product 3. 7.5 g of product 3 was added to a mixed solution of 160 mL of pyridine and 20 mL of distilled water, heated to reflux to dissolve, and then 22 g of potassium permanganate was added. The reaction was continued for 18 h, followed by the addition of ethanol, filtration, concentration, and purification to obtain product 4.

[0070] S3: Add 7g of product 4 to 45mL of acetic anhydride, heat to reflux until dissolved, stir and react for 4h, concentrate and purify to obtain product 5. Mix 8g of product 5, 7g of epoxy acrylate and 0.03g of 2-hydroxy-2-methyl-1-phenylpropanone to obtain composite curing agent.

[0071] This embodiment discloses an epoxy resin for fiber optic arrays, which is composed of the following components by weight: 80 parts bisphenol F type epoxy resin, 5 parts modified functional resin, 5 parts dibutyl phthalate, 5 parts silane coupling agent KH-550, and 5 parts composite curing agent.

[0072] This embodiment discloses a method for preparing epoxy resin for fiber optic arrays, including the following steps:

[0073] Step 1: Under nitrogen protection, bisphenol F epoxy resin and modified functional resin are added to the reactor, heated and stirred to react, and a mixture is obtained.

[0074] Step 2: Add dibutyl phthalate and silane coupling agent KH-550 to the mixture, continue stirring, cool down, add composite curing agent, stir, vacuum degas, filter, and obtain epoxy resin for fiber array.

[0075] Comparative Example 1: Compared with Example 1, Comparative Example 1 did not add modified functional resin during the preparation of epoxy resin, and all other conditions remained unchanged.

[0076] Comparative Example 2: Compared with Example 1, Comparative Example 2 used epoxy acrylate and 2-hydroxy-2-methyl-1-phenylpropanone instead of the composite curing agent in the preparation of epoxy resin, while keeping other conditions unchanged.

[0077] Performance testing

[0078] The samples prepared according to Examples 1-3 and Comparative Examples 1-2 were subjected to performance tests. After curing with 700 mW UV for 200 s, the samples were then cured at 85 °C for 120 min. The thermal stability of the samples was tested using thermogravimetric analysis. The tensile and compressive properties of the samples were tested according to GB / T 2567-2021. The density (ρ1) of the uncured samples was tested according to GB / T 15223-2008. The density (ρ2) of the cured samples was tested according to GB / T1033.1-2022. The shrinkage rate was calculated as [(ρ2-ρ1) / ρ2]×100%. The test results are shown in Table 1.

[0079] Table 1

[0080] project Decomposition temperature / °C Tensile strength / MPa Compressive strength / MPa Shrinkage rate / % Example 1 415.96 98.64 164.56 0.92 Example 2 415.32 97.83 163.75 0.95 Example 3 415.41 98.12 163.62 0.96 Comparative Example 1 362.43 74.34 115.75 1.47 Comparative Example 2 361.48 72.57 113.22 1.52

[0081] As shown in Table 1, the test results indicate that epoxy resins with excellent thermal stability, mechanical properties, and low shrinkage can be prepared using the methods described in Examples 1-3. A comparison between Comparative Example 1 and Examples 1-3 reveals that adding modified functional resins can effectively improve the thermal stability and mechanical properties of epoxy resins, and also reduce their shrinkage. A comparison between Comparative Example 2 and Examples 1-3 shows that adding composite curing agents can effectively improve the thermal stability and mechanical properties of epoxy resins, and also reduce their shrinkage.

[0082] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0083] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An epoxy resin for fiber optic arrays, characterized in that, It is composed of the following components by weight: 50-80 parts epoxy resin, 5-30 parts modified functional resin, 5-10 parts toughening agent, 1-5 parts additives, and 5-20 parts composite curing agent. The preparation method of the modified functional resin includes the following steps: Q1: 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, ditert-butyl dicarbonate and nano-iron oxide were added to anhydrous ethanol and stirred at room temperature. After the reaction was completed, the mixture was filtered, evaporated to dryness, dissolved, washed, separated, and evaporated to dryness to obtain compound a. Q2: Sodium tripolyphosphate, p-chlorophenylglycine and acetone were added to a container in sequence. Cinnamyl chloride was added to the acetone and stirred until dissolved. The solution was then added dropwise to the container. After the addition was complete, the reaction continued. The mixture was filtered, washed, and dried to obtain compound b. Q3: Compound a and triethylamine were added to dichloromethane, stirred, and placed in an ice bath to cool. A mixed solution of compound b and dichloromethane was added, and the mixture was stirred at room temperature. After the reaction was completed, saturated sodium bicarbonate solution was added, the mixture was washed, separated, and the organic phase was collected, dried, purified by vacuum distillation, and filtered to obtain compound c. Compound c was added to a container and heated in an oil bath to react. After the reaction was completed, the mixture was cooled, purified, and filtered to obtain the modified diamine. Q4: Add the modified diamine and 4,4'-diaminodiphenyl ether to N-methylpyrrolidone, stir to dissolve, cool in an ice bath, then add hexafluorodianhydride, react in an ice bath, react at room temperature, then add a mixed solution of anhydrous acetic anhydride and anhydrous triethylamine, heat to react, then add to ethanol, wash, centrifuge, and vacuum dry to obtain the modified functional resin. The preparation method of the composite curing agent includes the following steps: S1: 2,3,6,7-Tetramethylanthracene-9,10-dione was added to a container. Under nitrogen protection, cesium fluoride and tetrahydrofuran were added. After stirring at low temperature, trimethyl(trifluoromethyl)silane was added. After stirring, the mixture was heated to a higher temperature. After the reaction was completed, the mixture was filtered, washed, and purified to obtain product 1. Product 1 was added to tetrahydrofuran and heated under reflux until dissolved. Then concentrated hydrochloric acid was added, the mixture was stirred, cooled, filtered, and washed to obtain product 2. S2: Under nitrogen protection, product 2 was added to a container containing anhydrous benzene, stirred, cooled, and trifluoromethanesulfonic acid was added. The reaction continued, distilled water was added, the product was extracted, evaporated to dryness, and purified to obtain product 3. Product 3 was added to a mixed solution of pyridine and distilled water, heated to reflux to dissolve, potassium permanganate was added, the reaction continued, ethanol was added, filtered, concentrated, and purified to obtain product 4. S3: Add product 4 to acetic anhydride, heat to reflux until dissolved, stir to react, concentrate, purify to obtain product 5, mix product 5, epoxy acrylate and 2-hydroxy-2-methyl-1-phenylpropanone to obtain composite curing agent.

2. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In Q1, the ratio of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, ditert-butyl dicarbonate, nano-ferric oxide, and anhydrous ethanol is (6.32-7.01) g : (4.38-4.59) g : (0.21-0.35) g : (55-65) mL.

3. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In Q2, the ratio of sodium tripolyphosphate, p-chlorophenylglycine, and cinnamoyl chloride is (8.52-9.16) g: (5.38-5.46) g: (7.81-8.17) g; in Q3, the molar ratio of compound a, triethylamine, and compound b is (1-1.3): (2.2-2.6): (2.2-2.8).

4. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In Q4, the ratio of modified diamine, 4,4'-diaminodiphenyl ether, N-methylpyrrolidone, hexafluorodianhydride, anhydrous acetic anhydride, and anhydrous triethylamine is (0.073-0.082) g : (0.64-0.78) g : (6.5-8.5) mL : (1.91-2.17) g : (2.11-2.32) mL : (3.12-3.28) mL.

5. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In S1, the ratio of 2,3,6,7-tetramethylanthracene-9,10-dione, cesium fluoride, tetrahydrofuran, and trimethyl(trifluoromethyl)silane is (10-12) g : (0.057-0.082) g : (500-600) mL : (6-9) mL; the ratio of product 1 to tetrahydrofuran is (10-12) g : (20-25) mL.

6. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In S2, the ratio of product 2, anhydrous benzene and trifluoromethanesulfonic acid is (5-7.5) g: (10-20) mL: (10-14) mL; the ratio of product 3, pyridine, distilled water and potassium permanganate is (5-7.5) g: (160-180) mL: (20-40) mL: (18-22) g.

7. The epoxy resin for fiber optic arrays according to claim 1, characterized in that, In S3, the ratio of product 4 to acetic anhydride is (5-7) g: (30-45) mL; the ratio of product 5, epoxy acrylate and 2-hydroxy-2-methyl-1-phenylpropanone is (3-8) g: (2-7) g: (0.03-0.05) g.

8. A method for preparing an epoxy resin for fiber optic arrays as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Under nitrogen protection, epoxy resin and modified functional resin are added to the reactor, heated and stirred to react, and a mixture is obtained. Step 2: Add toughening agent and additives to the mixture, continue stirring, cool down, add composite curing agent, stir, vacuum degas, filter, and obtain epoxy resin for fiber array.

Images